Parameterizing Coefficients of a POD-Based Dynamical System
NASA Technical Reports Server (NTRS)
Kalb, Virginia L.
2010-01-01
A method of parameterizing the coefficients of a dynamical system based of a proper orthogonal decomposition (POD) representing the flow dynamics of a viscous fluid has been introduced. (A brief description of POD is presented in the immediately preceding article.) The present parameterization method is intended to enable construction of the dynamical system to accurately represent the temporal evolution of the flow dynamics over a range of Reynolds numbers. The need for this or a similar method arises as follows: A procedure that includes direct numerical simulation followed by POD, followed by Galerkin projection to a dynamical system has been proven to enable representation of flow dynamics by a low-dimensional model at the Reynolds number of the simulation. However, a more difficult task is to obtain models that are valid over a range of Reynolds numbers. Extrapolation of low-dimensional models by use of straightforward Reynolds-number-based parameter continuation has proven to be inadequate for successful prediction of flows. A key part of the problem of constructing a dynamical system to accurately represent the temporal evolution of the flow dynamics over a range of Reynolds numbers is the problem of understanding and providing for the variation of the coefficients of the dynamical system with the Reynolds number. Prior methods do not enable capture of temporal dynamics over ranges of Reynolds numbers in low-dimensional models, and are not even satisfactory when large numbers of modes are used. The basic idea of the present method is to solve the problem through a suitable parameterization of the coefficients of the dynamical system. The parameterization computations involve utilization of the transfer of kinetic energy between modes as a function of Reynolds number. The thus-parameterized dynamical system accurately predicts the flow dynamics and is applicable to a range of flow problems in the dynamical regime around the Hopf bifurcation. Parameter-continuation software can be used on the parameterized dynamical system to derive a bifurcation diagram that accurately predicts the temporal flow behavior.
Dynamic PROOF clusters with PoD: architecture and user experience
NASA Astrophysics Data System (ADS)
Manafov, Anar
2011-12-01
PROOF on Demand (PoD) is a tool-set, which sets up a PROOF cluster on any resource management system. PoD is a user oriented product with an easy to use GUI and a command-line interface. It is fully automated. No administrative privileges or special knowledge is required to use it. PoD utilizes a plug-in system, to use different job submission front-ends. The current PoD distribution is shipped with LSF, Torque (PBS), Grid Engine, Condor, gLite, and SSH plug-ins. The product is to be extended. We therefore plan to implement a plug-in for AliEn Grid as well. Recently developed algorithms made it possible to efficiently maintain two types of connections: packet-forwarding and native PROOF connections. This helps to properly handle most kinds of workers, with and without firewalls. PoD maintains the PROOF environment automatically and, for example, prevents resource misusage in case when workers idle for too long. As PoD matures as a product and provides more plug-ins, it's used as a standard for setting up dynamic PROOF clusters in many different institutions. The GSI Analysis Facility (GSIAF) is in production since 2007. The static PROOF cluster has been phased out end of 2009. GSIAF is now completely based on PoD. Users create private dynamic PROOF clusters on the general purpose batch farm. This provides an easier resource sharing between interactive local batch and Grid usage. The main user communities are FAIR and ALICE.
Algorithm for Stabilizing a POD-Based Dynamical System
NASA Technical Reports Server (NTRS)
Kalb, Virginia L.
2010-01-01
This algorithm provides a new way to improve the accuracy and asymptotic behavior of a low-dimensional system based on the proper orthogonal decomposition (POD). Given a data set representing the evolution of a system of partial differential equations (PDEs), such as the Navier-Stokes equations for incompressible flow, one may obtain a low-dimensional model in the form of ordinary differential equations (ODEs) that should model the dynamics of the flow. Temporal sampling of the direct numerical simulation of the PDEs produces a spatial time series. The POD extracts the temporal and spatial eigenfunctions of this data set. Truncated to retain only the most energetic modes followed by Galerkin projection of these modes onto the PDEs obtains a dynamical system of ordinary differential equations for the time-dependent behavior of the flow. In practice, the steps leading to this system of ODEs entail numerically computing first-order derivatives of the mean data field and the eigenfunctions, and the computation of many inner products. This is far from a perfect process, and often results in the lack of long-term stability of the system and incorrect asymptotic behavior of the model. This algorithm describes a new stabilization method that utilizes the temporal eigenfunctions to derive correction terms for the coefficients of the dynamical system to significantly reduce these errors.
A novel coupling of noise reduction algorithms for particle flow simulations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zimoń, M.J., E-mail: malgorzata.zimon@stfc.ac.uk; James Weir Fluids Lab, Mechanical and Aerospace Engineering Department, The University of Strathclyde, Glasgow G1 1XJ; Reese, J.M.
2016-09-15
Proper orthogonal decomposition (POD) and its extension based on time-windows have been shown to greatly improve the effectiveness of recovering smooth ensemble solutions from noisy particle data. However, to successfully de-noise any molecular system, a large number of measurements still need to be provided. In order to achieve a better efficiency in processing time-dependent fields, we have combined POD with a well-established signal processing technique, wavelet-based thresholding. In this novel hybrid procedure, the wavelet filtering is applied within the POD domain and referred to as WAVinPOD. The algorithm exhibits promising results when applied to both synthetically generated signals and particlemore » data. In this work, the simulations compare the performance of our new approach with standard POD or wavelet analysis in extracting smooth profiles from noisy velocity and density fields. Numerical examples include molecular dynamics and dissipative particle dynamics simulations of unsteady force- and shear-driven liquid flows, as well as phase separation phenomenon. Simulation results confirm that WAVinPOD preserves the dimensionality reduction obtained using POD, while improving its filtering properties through the sparse representation of data in wavelet basis. This paper shows that WAVinPOD outperforms the other estimators for both synthetically generated signals and particle-based measurements, achieving a higher signal-to-noise ratio from a smaller number of samples. The new filtering methodology offers significant computational savings, particularly for multi-scale applications seeking to couple continuum informations with atomistic models. It is the first time that a rigorous analysis has compared de-noising techniques for particle-based fluid simulations.« less
Uncertainty and operational considerations in mass prophylaxis workforce planning.
Hupert, Nathaniel; Xiong, Wei; King, Kathleen; Castorena, Michelle; Hawkins, Caitlin; Wu, Cindie; Muckstadt, John A
2009-12-01
The public health response to an influenza pandemic or other large-scale health emergency may include mass prophylaxis using multiple points of dispensing (PODs) to deliver countermeasures rapidly to affected populations. Computer models created to date to determine "optimal" staffing levels at PODs typically assume stable patient demand for service. The authors investigated POD function under dynamic and uncertain operational environments. The authors constructed a Monte Carlo simulation model of mass prophylaxis (the Dynamic POD Simulator, or D-PODS) to assess the consequences of nonstationary patient arrival patterns on POD function under a variety of POD layouts and staffing plans. Compared are the performance of a standard POD layout under steady-state and variable patient arrival rates that may mimic real-life variation in patient demand. To achieve similar performance, PODs functioning under nonstationary patient arrival rates require higher staffing levels than would be predicted using the assumption of stationary arrival rates. Furthermore, PODs may develop severe bottlenecks unless staffing levels vary over time to meet changing patient arrival patterns. Efficient POD networks therefore require command and control systems capable of dynamically adjusting intra- and inter-POD staff levels to meet demand. In addition, under real-world operating conditions of heightened uncertainty, fewer large PODs will require a smaller total staff than many small PODs to achieve comparable performance. Modeling environments that capture the effects of fundamental uncertainties in public health disasters are essential for the realistic evaluation of response mechanisms and policies. D-PODS quantifies POD operational efficiency under more realistic conditions than have been modeled previously. The authors' experiments demonstrate that effective POD staffing plans must be responsive to variation and uncertainty in POD arrival patterns. These experiments highlight the need for command and control systems to be created to manage emergency response successfully.
POD/DEIM reduced-order strategies for efficient four dimensional variational data assimilation
NASA Astrophysics Data System (ADS)
Ştefănescu, R.; Sandu, A.; Navon, I. M.
2015-08-01
This work studies reduced order modeling (ROM) approaches to speed up the solution of variational data assimilation problems with large scale nonlinear dynamical models. It is shown that a key requirement for a successful reduced order solution is that reduced order Karush-Kuhn-Tucker conditions accurately represent their full order counterparts. In particular, accurate reduced order approximations are needed for the forward and adjoint dynamical models, as well as for the reduced gradient. New strategies to construct reduced order based are developed for proper orthogonal decomposition (POD) ROM data assimilation using both Galerkin and Petrov-Galerkin projections. For the first time POD, tensorial POD, and discrete empirical interpolation method (DEIM) are employed to develop reduced data assimilation systems for a geophysical flow model, namely, the two dimensional shallow water equations. Numerical experiments confirm the theoretical framework for Galerkin projection. In the case of Petrov-Galerkin projection, stabilization strategies must be considered for the reduced order models. The new reduced order shallow water data assimilation system provides analyses similar to those produced by the full resolution data assimilation system in one tenth of the computational time.
POD/DEIM reduced-order strategies for efficient four dimensional variational data assimilation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ştefănescu, R., E-mail: rstefane@vt.edu; Sandu, A., E-mail: sandu@cs.vt.edu; Navon, I.M., E-mail: inavon@fsu.edu
2015-08-15
This work studies reduced order modeling (ROM) approaches to speed up the solution of variational data assimilation problems with large scale nonlinear dynamical models. It is shown that a key requirement for a successful reduced order solution is that reduced order Karush–Kuhn–Tucker conditions accurately represent their full order counterparts. In particular, accurate reduced order approximations are needed for the forward and adjoint dynamical models, as well as for the reduced gradient. New strategies to construct reduced order based are developed for proper orthogonal decomposition (POD) ROM data assimilation using both Galerkin and Petrov–Galerkin projections. For the first time POD, tensorialmore » POD, and discrete empirical interpolation method (DEIM) are employed to develop reduced data assimilation systems for a geophysical flow model, namely, the two dimensional shallow water equations. Numerical experiments confirm the theoretical framework for Galerkin projection. In the case of Petrov–Galerkin projection, stabilization strategies must be considered for the reduced order models. The new reduced order shallow water data assimilation system provides analyses similar to those produced by the full resolution data assimilation system in one tenth of the computational time.« less
POD Model Reconstruction for Gray-Box Fault Detection
NASA Technical Reports Server (NTRS)
Park, Han; Zak, Michail
2007-01-01
Proper orthogonal decomposition (POD) is the mathematical basis of a method of constructing low-order mathematical models for the "gray-box" fault-detection algorithm that is a component of a diagnostic system known as beacon-based exception analysis for multi-missions (BEAM). POD has been successfully applied in reducing computational complexity by generating simple models that can be used for control and simulation for complex systems such as fluid flows. In the present application to BEAM, POD brings the same benefits to automated diagnosis. BEAM is a method of real-time or offline, automated diagnosis of a complex dynamic system.The gray-box approach makes it possible to utilize incomplete or approximate knowledge of the dynamics of the system that one seeks to diagnose. In the gray-box approach, a deterministic model of the system is used to filter a time series of system sensor data to remove the deterministic components of the time series from further examination. What is left after the filtering operation is a time series of residual quantities that represent the unknown (or at least unmodeled) aspects of the behavior of the system. Stochastic modeling techniques are then applied to the residual time series. The procedure for detecting abnormal behavior of the system then becomes one of looking for statistical differences between the residual time series and the predictions of the stochastic model.
Designing Extraterrestrial Plant Growth Habitats With Low Pressure Atmospheres
NASA Technical Reports Server (NTRS)
Corey, Kenneth A.
2001-01-01
In-situ resource utilization, provision of human life support requirements by bioregenerative methods, and engineering constraints for construction and deployment of plant growth structures on the surface of Mars all suggest the need for plant growth studies at hypobaric pressures. Past work demonstrated that plants will likely tolerate and grow at pressures at or below 10 kPa. Based upon this premise, concepts are developed for the design of reduced pressure atmospheres in lightweight, inflatable structures for plant growth systems on Mars with the goals of maximizing design simplicity and the use of local resources. A modular pod design is proposed as it could be integrated with large-scale production systems. Atmospheric modification of pod clusters would be based upon a pulse and scrub system using mass flow methods for atmospheric transport. A specific modification and control scenario is developed for a lettuce pod to illustrate the dynamics of carbon dioxide and oxygen exchange within a pod. Considerations of minimal atmospheric crop requirements will aid in the development of engineering designs and strategies for extraterrestrial plant growth structures that employ rarefied atmospheres.
Designing Extraterrestrial Plant Growth Habitats with Low Pressure Atmospheres
NASA Technical Reports Server (NTRS)
Corey, Kenneth A.
2002-01-01
In-situ resource utilization, provision of human life support requirements by bioregenerative methods, and engineering constraints for construction and deployment of plant growth structures on the surface of Mars all suggest the need for plant growth studies at hypobaric pressures. Past work demonstrated that plants will likely tolerate and grow at pressures at or below 10 kPa. Based upon this premise, concepts are developed for the design of reduced pressure atmospheres in lightweight, inflatable structures for plant growth systems on Mars with the goals of maximizing design simplicity and the use of local resources. A modular pod design is proposed as it could be integrated with large-scale production systems. Atmospheric modification of pod clusters would be based upon a pulse and scrub system using mass flow methods for atmospheric transport. A specific modification and control scenario is developed for a lettuce pod to illustrate the dynamics of carbon dioxide and oxygen exchange within a pod. Considerations of minimal atmospheric crop requirements will aid in the development of engineering designs and strategies for extraterrestrial plant growth structures that employ rarefied atmospheres.
Proper orthogonal decomposition-based spectral higher-order stochastic estimation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Baars, Woutijn J., E-mail: wbaars@unimelb.edu.au; Tinney, Charles E.
A unique routine, capable of identifying both linear and higher-order coherence in multiple-input/output systems, is presented. The technique combines two well-established methods: Proper Orthogonal Decomposition (POD) and Higher-Order Spectra Analysis. The latter of these is based on known methods for characterizing nonlinear systems by way of Volterra series. In that, both linear and higher-order kernels are formed to quantify the spectral (nonlinear) transfer of energy between the system's input and output. This reduces essentially to spectral Linear Stochastic Estimation when only first-order terms are considered, and is therefore presented in the context of stochastic estimation as spectral Higher-Order Stochastic Estimationmore » (HOSE). The trade-off to seeking higher-order transfer kernels is that the increased complexity restricts the analysis to single-input/output systems. Low-dimensional (POD-based) analysis techniques are inserted to alleviate this void as POD coefficients represent the dynamics of the spatial structures (modes) of a multi-degree-of-freedom system. The mathematical framework behind this POD-based HOSE method is first described. The method is then tested in the context of jet aeroacoustics by modeling acoustically efficient large-scale instabilities as combinations of wave packets. The growth, saturation, and decay of these spatially convecting wave packets are shown to couple both linearly and nonlinearly in the near-field to produce waveforms that propagate acoustically to the far-field for different frequency combinations.« less
Fully Three-Dimensional Virtual-Reality System
NASA Technical Reports Server (NTRS)
Beckman, Brian C.
1994-01-01
Proposed virtual-reality system presents visual displays to simulate free flight in three-dimensional space. System, virtual space pod, is testbed for control and navigation schemes. Unlike most virtual-reality systems, virtual space pod would not depend for orientation on ground plane, which hinders free flight in three dimensions. Space pod provides comfortable seating, convenient controls, and dynamic virtual-space images for virtual traveler. Controls include buttons plus joysticks with six degrees of freedom.
Robust/optimal temperature profile control of a high-speed aerospace vehicle using neural networks.
Yadav, Vivek; Padhi, Radhakant; Balakrishnan, S N
2007-07-01
An approximate dynamic programming (ADP)-based suboptimal neurocontroller to obtain desired temperature for a high-speed aerospace vehicle is synthesized in this paper. A 1-D distributed parameter model of a fin is developed from basic thermal physics principles. "Snapshot" solutions of the dynamics are generated with a simple dynamic inversion-based feedback controller. Empirical basis functions are designed using the "proper orthogonal decomposition" (POD) technique and the snapshot solutions. A low-order nonlinear lumped parameter system to characterize the infinite dimensional system is obtained by carrying out a Galerkin projection. An ADP-based neurocontroller with a dual heuristic programming (DHP) formulation is obtained with a single-network-adaptive-critic (SNAC) controller for this approximate nonlinear model. Actual control in the original domain is calculated with the same POD basis functions through a reverse mapping. Further contribution of this paper includes development of an online robust neurocontroller to account for unmodeled dynamics and parametric uncertainties inherent in such a complex dynamic system. A neural network (NN) weight update rule that guarantees boundedness of the weights and relaxes the need for persistence of excitation (PE) condition is presented. Simulation studies show that in a fairly extensive but compact domain, any desired temperature profile can be achieved starting from any initial temperature profile. Therefore, the ADP and NN-based controllers appear to have the potential to become controller synthesis tools for nonlinear distributed parameter systems.
Proper Orthogonal Decomposition in Optimal Control of Fluids
NASA Technical Reports Server (NTRS)
Ravindran, S. S.
1999-01-01
In this article, we present a reduced order modeling approach suitable for active control of fluid dynamical systems based on proper orthogonal decomposition (POD). The rationale behind the reduced order modeling is that numerical simulation of Navier-Stokes equations is still too costly for the purpose of optimization and control of unsteady flows. We examine the possibility of obtaining reduced order models that reduce computational complexity associated with the Navier-Stokes equations while capturing the essential dynamics by using the POD. The POD allows extraction of certain optimal set of basis functions, perhaps few, from a computational or experimental data-base through an eigenvalue analysis. The solution is then obtained as a linear combination of these optimal set of basis functions by means of Galerkin projection. This makes it attractive for optimal control and estimation of systems governed by partial differential equations. We here use it in active control of fluid flows governed by the Navier-Stokes equations. We show that the resulting reduced order model can be very efficient for the computations of optimization and control problems in unsteady flows. Finally, implementational issues and numerical experiments are presented for simulations and optimal control of fluid flow through channels.
Low Dimensional Tools for Flow-Structure Interaction Problems: Application to Micro Air Vehicles
NASA Technical Reports Server (NTRS)
Schmit, Ryan F.; Glauser, Mark N.; Gorton, Susan A.
2003-01-01
A low dimensional tool for flow-structure interaction problems based on Proper Orthogonal Decomposition (POD) and modified Linear Stochastic Estimation (mLSE) has been proposed and was applied to a Micro Air Vehicle (MAV) wing. The method utilizes the dynamic strain measurements from the wing to estimate the POD expansion coefficients from which an estimation of the velocity in the wake can be obtained. For this experiment the MAV wing was set at five different angles of attack, from 0 deg to 20 deg. The tunnel velocities varied from 44 to 58 ft/sec with corresponding Reynolds numbers of 46,000 to 70,000. A stereo Particle Image Velocimetry (PIV) system was used to measure the wake of the MAV wing simultaneously with the signals from the twelve dynamic strain gauges mounted on the wing. With 20 out of 2400 POD modes, a reasonable estimation of the flow flow was observed. By increasing the number of POD modes, a better estimation of the flow field will occur. Utilizing the simultaneously sampled strain gauges and flow field measurements in conjunction with mLSE, an estimation of the flow field with lower energy modes is reasonable. With these results, the methodology for estimating the wake flow field from just dynamic strain gauges is validated.
Model reconstruction using POD method for gray-box fault detection
NASA Technical Reports Server (NTRS)
Park, H. G.; Zak, M.
2003-01-01
This paper describes using Proper Orthogonal Decomposition (POD) method to create low-order dynamical models for the Model Filter component of Beacon-based Exception Analysis for Multi-missions (BEAM).
Ship electric propulsion simulator based on networking technology
NASA Astrophysics Data System (ADS)
Zheng, Huayao; Huang, Xuewu; Chen, Jutao; Lu, Binquan
2006-11-01
According the new ship building tense, a novel electric propulsion simulator (EPS) had been developed in Marine Simulation Center of SMU. The architecture, software function and FCS network technology of EPS and integrated power system (IPS) were described. In allusion to the POD propeller in ship, a special physical model was built. The POD power was supplied from the simulative 6.6 kV Medium Voltage Main Switchboard, its control could be realized in local or remote mode. Through LAN, the simulated feature information of EPS will pass to the physical POD model, which would reflect the real thruster working status in different sea conditions. The software includes vessel-propeller math module, thruster control system, distribution and emergency integrated management, double closed loop control system, vessel static water resistance and dynamic software; instructor main control software. The monitor and control system is realized by real time data collection system and CAN bus technology. During the construction, most devices such as monitor panels and intelligent meters, are developed in lab which were based on embedded microcomputer system with CAN interface to link the network. They had also successfully used in practice and would be suitable for the future demands of digitalization ship.
Implementation of a low-cost, commercial orbit determination system
NASA Technical Reports Server (NTRS)
Corrigan, Jim
1994-01-01
This paper describes the implementation and potential applications of a workstation-based orbit determination system developed by Storm Integration, Inc. called the Precision Orbit Determination System (PODS). PODS is offered as a layered product to the commercially-available Satellite Tool Kit (STK) produced by Analytical Graphics, Inc. PODS also incorporates the Workstation/Precision Orbit Determination (WS/POD) product offered by Van Martin System, Inc. The STK graphical user interface is used to access and invoke the PODS capabilities and to display the results. WS/POD is used to compute a best-fit solution to user-supplied tracking data. PODS provides the capability to simultaneously estimate the orbits of up to 99 satellites based on a wide variety of observation types including angles, range, range rate, and Global Positioning System (GPS) data. PODS can also estimate ground facility locations, Earth geopotential model coefficients, solar pressure and atmospheric drag parameters, and observation data biases. All determined data is automatically incorporated into the STK data base, which allows storage, manipulation and export of the data to other applications. PODS is offered in three levels: Standard, Basic GPS and Extended GPS. Standard allows processing of non-GPS observation types for any number of vehicles and facilities. Basic GPS adds processing of GPS pseudo-ranging data to the Standard capabilities. Extended GPS adds the ability to process GPS carrier phase data.
NASA Astrophysics Data System (ADS)
Mahmoud, Seedahmed S.; Visagathilagar, Yuvaraja; Katsifolis, Jim
2012-09-01
The success of any perimeter intrusion detection system depends on three important performance parameters: the probability of detection (POD), the nuisance alarm rate (NAR), and the false alarm rate (FAR). The most fundamental parameter, POD, is normally related to a number of factors such as the event of interest, the sensitivity of the sensor, the installation quality of the system, and the reliability of the sensing equipment. The suppression of nuisance alarms without degrading sensitivity in fiber optic intrusion detection systems is key to maintaining acceptable performance. Signal processing algorithms that maintain the POD and eliminate nuisance alarms are crucial for achieving this. In this paper, a robust event classification system using supervised neural networks together with a level crossings (LCs) based feature extraction algorithm is presented for the detection and recognition of intrusion and non-intrusion events in a fence-based fiber-optic intrusion detection system. A level crossings algorithm is also used with a dynamic threshold to suppress torrential rain-induced nuisance alarms in a fence system. Results show that rain-induced nuisance alarms can be suppressed for rainfall rates in excess of 100 mm/hr with the simultaneous detection of intrusion events. The use of a level crossing based detection and novel classification algorithm is also presented for a buried pipeline fiber optic intrusion detection system for the suppression of nuisance events and discrimination of intrusion events. The sensor employed for both types of systems is a distributed bidirectional fiber-optic Mach-Zehnder (MZ) interferometer.
Control of a HexaPOD treatment couch for robot-assisted radiotherapy.
Hermann, Christian; Ma, Lei; Wilbert, Jürgen; Baier, Kurt; Schilling, Klaus
2012-10-01
Moving tumors, for example in the vicinity of the lungs, pose a challenging problem in radiotherapy, as healthy tissue should not be irradiated. Apart from gating approaches, one standard method is to irradiate the complete volume within which a tumor moves plus a safety margin containing a considerable volume of healthy tissue. This work deals with a system for tumor motion compensation using the HexaPOD® robotic treatment couch (Medical Intelligence GmbH, Schwabmünchen, Germany). The HexaPOD, carrying the patient during treatment, is instructed to perform translational movements such that the tumor motion, from the beams-eye view of the linear accelerator, is eliminated. The dynamics of the HexaPOD are characterized by time delays, saturations, and other non-linearities that make the design of control a challenging task. The focus of this work lies on two control methods for the HexaPOD that can be used for reference tracking. The first method uses a model predictive controller based on a model gained through system identification methods, and the second method uses a position control scheme useful for reference tracking. We compared the tracking performance of both methods in various experiments with real hardware using ideal reference trajectories, prerecorded patient trajectories, and human volunteers whose breathing motion was compensated by the system.
NASA Astrophysics Data System (ADS)
Bird, Alan; Anderson, Scott A.; Linne von Berg, Dale; Davidson, Morgan; Holt, Niel; Kruer, Melvin; Wilson, Michael L.
2010-04-01
EyePod is a compact survey and inspection day/night imaging sensor suite for small unmanned aircraft systems (UAS). EyePod generates georeferenced image products in real-time from visible near infrared (VNIR) and long wave infrared (LWIR) imaging sensors and was developed under the ONR funded FEATHAR (Fusion, Exploitation, Algorithms, and Targeting for High-Altitude Reconnaissance) program. FEATHAR is being directed and executed by the Naval Research Laboratory (NRL) in conjunction with the Space Dynamics Laboratory (SDL) and FEATHAR's goal is to develop and test new tactical sensor systems specifically designed for small manned and unmanned platforms (payload weight < 50 lbs). The EyePod suite consists of two VNIR/LWIR (day/night) gimbaled sensors that, combined, provide broad area survey and focused inspection capabilities. Each EyePod sensor pairs an HD visible EO sensor with a LWIR bolometric imager providing precision geo-referenced and fully digital EO/IR NITFS output imagery. The LWIR sensor is mounted to a patent-pending jitter-reduction stage to correct for the high-frequency motion typically found on small aircraft and unmanned systems. Details will be presented on both the wide-area and inspection EyePod sensor systems, their modes of operation, and results from recent flight demonstrations.
NASA Technical Reports Server (NTRS)
Luthcke, Scott B.; Zelensky, Nikita P.; Rowlands, David D.; Lemoine, Frank G.; Williams, Teresa A.
2003-01-01
Jason-1, launched on December 7, 2001, is continuing the time series of centimeter level ocean topography observations as the follow-on to the highly successful TOPEX/POSEIDON (T/P) radar altimeter satellite. The precision orbit determination (POD) is a critical component to meeting the ocean topography goals of the mission. Jason-1 is no exception and has set a 1 cm radial orbit accuracy goal, which represents a factor of two improvement over what is currently being achieved for T/P. The challenge to precision orbit determination (POD) is both achieving the 1 cm radial orbit accuracy and evaluating and validating the performance of the 1 cm orbit. Fortunately, Jason-1 POD can rely on four independent tracking data types including near continuous tracking data from the dual frequency codeless BlackJack GPS receiver. In addition, to the enhanced GPS receiver, Jason-1 carries significantly improved SLR and DORIS tracking systems along with the altimeter itself. We demonstrate the 1 cm radial orbit accuracy goal has been achieved using GPS data alone in a reduced dynamic solution. It is also shown that adding SLR data to the GPS-based solutions improves the orbits even further. In order to assess the performance of these orbits it is necessary to process all of the available tracking data (GPS, SLR, DORIS and altimeter crossover differences) as either dependent or independent of the orbit solutions. It was also necessary to compute orbit solutions using various combinations of the four available tracking data in order to independently assess the orbit performance. Towards this end, we have greatly improved orbits determined solely from SLR+DORIS data by applying the reduced dynamic solution strategy. In addition, we have computed reduced dynamic orbits based on SLR, DORIS and crossover data that are a significant improvement over the SLR and DORIS based dynamic solutions. These solutions provide the best performing orbits for independent validation of the GPS-based reduced dynamic orbits.
Improved solution accuracy for TDRSS-based TOPEX/Poseidon orbit determination
NASA Technical Reports Server (NTRS)
Doll, C. E.; Mistretta, G. D.; Hart, R. C.; Oza, D. H.; Bolvin, D. T.; Cox, C. M.; Nemesure, M.; Niklewski, D. J.; Samii, M. V.
1994-01-01
Orbit determination results are obtained by the Goddard Space Flight Center (GSFC) Flight Dynamics Division (FDD) using a batch-least-squares estimator available in the Goddard Trajectory Determination System (GTDS) and an extended Kalman filter estimation system to process Tracking and Data Relay Satellite (TDRS) System (TDRSS) measurements. GTDS is the operational orbit determination system used by the FDD in support of the Ocean Topography Experiment (TOPEX)/Poseidon spacecraft navigation and health and safety operations. The extended Kalman filter was implemented in an orbit determination analysis prototype system, closely related to the Real-Time Orbit Determination System/Enhanced (RTOD/E) system. In addition, the Precision Orbit Determination (POD) team within the GSFC Space Geodesy Branch generated an independent set of high-accuracy trajectories to support the TOPEX/Poseidon scientific data. These latter solutions use the geodynamics (GEODYN) orbit determination system with laser ranging and Doppler Orbitography and Radiopositioning integrated by satellite (DORIS) tracking measurements. The TOPEX/Poseidon trajectories were estimated for November 7 through November 11, 1992, the timeframe under study. Independent assessments were made of the consistencies of solutions produced by the batch and sequential methods. The batch-least-squares solutions were assessed based on the solution residuals, while the sequential solutions were assessed based on primarily the estimated covariances. The batch-least-squares and sequential orbit solutions were compared with the definitive POD orbit solutions. The solution differences were generally less than 2 meters for the batch-least-squares and less than 13 meters for the sequential estimation solutions. After the sequential estimation solutions were processed with a smoother algorithm, position differences with POD orbit solutions of less than 7 meters were obtained. The differences among the POD, GTDS, and filter/smoother solutions can be traced to differences in modeling and tracking data types, which are being analyzed in detail.
Persistent model order reduction for complex dynamical systems using smooth orthogonal decomposition
NASA Astrophysics Data System (ADS)
Ilbeigi, Shahab; Chelidze, David
2017-11-01
Full-scale complex dynamic models are not effective for parametric studies due to the inherent constraints on available computational power and storage resources. A persistent reduced order model (ROM) that is robust, stable, and provides high-fidelity simulations for a relatively wide range of parameters and operating conditions can provide a solution to this problem. The fidelity of a new framework for persistent model order reduction of large and complex dynamical systems is investigated. The framework is validated using several numerical examples including a large linear system and two complex nonlinear systems with material and geometrical nonlinearities. While the framework is used for identifying the robust subspaces obtained from both proper and smooth orthogonal decompositions (POD and SOD, respectively), the results show that SOD outperforms POD in terms of stability, accuracy, and robustness.
Optimal design of UAV's pod shape
NASA Astrophysics Data System (ADS)
Wei, Qun; Jia, Hong-guang
2011-08-01
In the modern war, UAV(unmanned aircraft system) plays a more and more important role in the army. UAVs always carry electrical-optical reconnaissance systems. These systems are used to accomplish the missions of observing and reconnaissance the battlefield. For traditional UAV, the shape of the pod on UAV is sphericity. In addition, the pod of UAV not only has the job of observing and reconnaissance the battlefield, but its shape also has impact on the UAV's drag when it flies in the air. In this paper, two different kinds of pod models are set up, one is the traditional sphericity model, the other is a new model. Unstructured grid is used on the flow field. Using CFD(computational fluid dynamic) method, the results of the drags of the different kinds of pod are got. The drag's relationship between the pod and the UAV is obtained by comparing the results of simulations. After analyzing the results we can get: when UAV flies at low speed(0.3Ma{0.7Ma), the drag's difference between the two kinds of pod is little, the pod's drag takes a small part of the UAV's whole drag which is only about 14%. At transonic speed(0.8Ma{1.2Ma), the drag's difference between these two kinds of pod is getting bigger and bigger along with the speed goes higher. The traditional pod's drag is 1/3 of the UAV's whole drag value, but for the new pod, it is only 1/5. At supersonic speed(1.3Ma{2.0Ma), the traditional pod's drag goes up rapidly, but the new kind of pod's drag goes up slowly. This makes the difference between the two kinds of UAVs' total drag comes greater. For example, at 2Ma, the total drag of new UAV is only 2/3 of the traditional UAV. These results show: when the UAV flies at low speed, these two kinds of pod have little difference in drag. But if it flies at supersonic speed, the pod has great impact on the UAV's total drag, so the designer of UAV's pod should pay more attention on the out shape.
A Generalized Framework for Reduced-Order Modeling of a Wind Turbine Wake
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hamilton, Nicholas; Viggiano, Bianca; Calaf, Marc
A reduced-order model for a wind turbine wake is sought from large eddy simulation data. Fluctuating velocity fields are combined in the correlation tensor to form the kernel of the proper orthogonal decomposition (POD). Proper orthogonal decomposition modes resulting from the decomposition represent the spatially coherent turbulence structures in the wind turbine wake; eigenvalues delineate the relative amount of turbulent kinetic energy associated with each mode. Back-projecting the POD modes onto the velocity snapshots produces dynamic coefficients that express the amplitude of each mode in time. A reduced-order model of the wind turbine wake (wakeROM) is defined through a seriesmore » of polynomial parameters that quantify mode interaction and the evolution of each POD mode coefficients. The resulting system of ordinary differential equations models the wind turbine wake composed only of the large-scale turbulent dynamics identified by the POD. Tikhonov regularization is used to recalibrate the dynamical system by adding additional constraints to the minimization seeking polynomial parameters, reducing error in the modeled mode coefficients. The wakeROM is periodically reinitialized with new initial conditions found by relating the incoming turbulent velocity to the POD mode coefficients through a series of open-loop transfer functions. The wakeROM reproduces mode coefficients to within 25.2%, quantified through the normalized root-mean-square error. A high-level view of the modeling approach is provided as a platform to discuss promising research directions, alternate processes that could benefit stability and efficiency, and desired extensions of the wakeROM.« less
Data-driven sensor placement from coherent fluid structures
NASA Astrophysics Data System (ADS)
Manohar, Krithika; Kaiser, Eurika; Brunton, Bingni W.; Kutz, J. Nathan; Brunton, Steven L.
2017-11-01
Optimal sensor placement is a central challenge in the prediction, estimation and control of fluid flows. We reinterpret sensor placement as optimizing discrete samples of coherent fluid structures for full state reconstruction. This permits a drastic reduction in the number of sensors required for faithful reconstruction, since complex fluid interactions can often be described by a small number of coherent structures. Our work optimizes point sensors using the pivoted matrix QR factorization to sample coherent structures directly computed from flow data. We apply this sampling technique in conjunction with various data-driven modal identification methods, including the proper orthogonal decomposition (POD) and dynamic mode decomposition (DMD). In contrast to POD-based sensors, DMD demonstrably enables the optimization of sensors for prediction in systems exhibiting multiple scales of dynamics. Finally, reconstruction accuracy from pivot sensors is shown to be competitive with sensors obtained using traditional computationally prohibitive optimization methods.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mutaf, Yildirim D.; Yi, Byong Yong; Prado, Karl
Purpose: A dedicated stereotactic gamma irradiation device, the GammaPod Trade-Mark-Sign from Xcision Medical Systems, was developed specifically to treat small breast cancers. This study presents the first evaluation of dosimetric and geometric characteristics from the initial prototype installed at University of Maryland Radiation Oncology Department. Methods: The GammaPod Trade-Mark-Sign stereotactic radiotherapy device is an assembly of a hemi-spherical source carrier containing 36 {sup 60}Co sources, a tungsten collimator, a dynamically controlled patient support table, and the breast immobilization system which also functions as a stereotactic frame. The source carrier contains the sources in six columns spaced longitudinally at 60 Degree-Signmore » intervals and it rotates together with the variable-size collimator to form 36 noncoplanar, concentric arcs focused at the isocenter. The patient support table enables motion in three dimensions to position the patient tumor at the focal point of the irradiation. The table moves continuously in three cardinal dimensions during treatment to provide dynamic shaping of the dose distribution. The breast is immobilized using a breast cup applying a small negative pressure, where the immobilization cup is embedded with fiducials also functioning as the stereotactic frame for the breast. Geometric and dosimetric evaluations of the system as well as a protocol for absorbed dose calibration are provided. Dosimetric verifications of dynamically delivered patient plans are performed for seven patients using radiochromic films in hypothetical preop, postop, and target-in-target treatment scenarios. Results: Loaded with 36 {sup 60}Co sources with cumulative activity of 4320 Ci, the prototype GammaPod Trade-Mark-Sign unit delivers 5.31 Gy/min at the isocenter using the largest 2.5 cm diameter collimator. Due to the noncoplanar beam arrangement and dynamic dose shaping features, the GammaPod Trade-Mark-Sign device is found to deliver uniform doses to targets with good conformity. The spatial accuracy of the device to locate the radiation isocenter is determined to be less than 1 mm. Single shot profiles with 2.5 cm collimator are measured with radiochromic film and found to be in good agreement with respect to the Monte Carlo based calculations (congruence of FWHM less than 1 mm). Dosimetric verifications corresponding to all hypothetical treatment plans corresponding to three target scenarios for each of the seven patients demonstrated good agreement with gamma index pass rates of better than 97% (99.0%{+-} 0.7%). Conclusions: Dosimetric evaluation of the first GammaPod Trade-Mark-Sign stereotactic breast radiotherapy unit was performed and the dosimetric and spatial accuracy of this novel technology is found to be feasible with respect to clinical radiotherapy standards. The observed level of agreement between the treatment planning system calculations and dosimetric measurements has confirmed that the system can deliver highly complex treatment plans with remarkable geometric and dosimetric accuracy.« less
System Identification and POD Method Applied to Unsteady Aerodynamics
NASA Technical Reports Server (NTRS)
Tang, Deman; Kholodar, Denis; Juang, Jer-Nan; Dowell, Earl H.
2001-01-01
The representation of unsteady aerodynamic flow fields in terms of global aerodynamic modes has proven to be a useful method for reducing the size of the aerodynamic model over those representations that use local variables at discrete grid points in the flow field. Eigenmodes and Proper Orthogonal Decomposition (POD) modes have been used for this purpose with good effect. This suggests that system identification models may also be used to represent the aerodynamic flow field. Implicit in the use of a systems identification technique is the notion that a relative small state space model can be useful in describing a dynamical system. The POD model is first used to show that indeed a reduced order model can be obtained from a much larger numerical aerodynamical model (the vortex lattice method is used for illustrative purposes) and the results from the POD and the system identification methods are then compared. For the example considered, the two methods are shown to give comparable results in terms of accuracy and reduced model size. The advantages and limitations of each approach are briefly discussed. Both appear promising and complementary in their characteristics.
Reduced-order model for dynamic optimization of pressure swing adsorption processes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Agarwal, A.; Biegler, L.; Zitney, S.
2007-01-01
Over the past decades, pressure swing adsorption (PSA) processes have been widely used as energy-efficient gas and liquid separation techniques, especially for high purity hydrogen purification from refinery gases. The separation processes are based on solid-gas equilibrium and operate under periodic transient conditions. Models for PSA processes are therefore multiple instances of partial differential equations (PDEs) in time and space with periodic boundary conditions that link the processing steps together. The solution of this coupled stiff PDE system is governed by steep concentrations and temperature fronts moving with time. As a result, the optimization of such systems for either designmore » or operation represents a significant computational challenge to current differential algebraic equation (DAE) optimization techniques and nonlinear programming algorithms. Model reduction is one approach to generate cost-efficient low-order models which can be used as surrogate models in the optimization problems. The study develops a reduced-order model (ROM) based on proper orthogonal decomposition (POD), which is a low-dimensional approximation to a dynamic PDE-based model. Initially, a representative ensemble of solutions of the dynamic PDE system is constructed by solving a higher-order discretization of the model using the method of lines, a two-stage approach that discretizes the PDEs in space and then integrates the resulting DAEs over time. Next, the ROM method applies the Karhunen-Loeve expansion to derive a small set of empirical eigenfunctions (POD modes) which are used as basis functions within a Galerkin's projection framework to derive a low-order DAE system that accurately describes the dominant dynamics of the PDE system. The proposed method leads to a DAE system of significantly lower order, thus replacing the one obtained from spatial discretization before and making optimization problem computationally-efficient. The method has been applied to the dynamic coupled PDE-based model of a two-bed four-step PSA process for separation of hydrogen from methane. Separate ROMs have been developed for each operating step with different POD modes for each of them. A significant reduction in the order of the number of states has been achieved. The gas-phase mole fraction, solid-state loading and temperature profiles from the low-order ROM and from the high-order simulations have been compared. Moreover, the profiles for a different set of inputs and parameter values fed to the same ROM were compared with the accurate profiles from the high-order simulations. Current results indicate the proposed ROM methodology as a promising surrogate modeling technique for cost-effective optimization purposes. Moreover, deviations from the ROM for different set of inputs and parameters suggest that a recalibration of the model is required for the optimization studies. Results for these will also be presented with the aforementioned results.« less
Observations on the Proper Orthogonal Decomposition
NASA Technical Reports Server (NTRS)
Berkooz, Gal
1992-01-01
The Proper Orthogonal Decomposition (P.O.D.), also known as the Karhunen-Loeve expansion, is a procedure for decomposing a stochastic field in an L(2) optimal sense. It is used in diverse disciplines from image processing to turbulence. Recently the P.O.D. is receiving much attention as a tool for studying dynamics of systems in infinite dimensional space. This paper reviews the mathematical fundamentals of this theory. Also included are results on the span of the eigenfunction basis, a geometric corollary due to Chebyshev's inequality and a relation between the P.O.D. symmetry and ergodicity.
NASA Astrophysics Data System (ADS)
Li, Kai; Zhou, Xuhua; Guo, Nannan; Zhao, Gang; Xu, Kexin; Lei, Weiwei
2017-09-01
Zero-difference kinematic, dynamic and reduced-dynamic precise orbit determination (POD) are three methods to obtain the precise orbits of Low Earth Orbit satellites (LEOs) by using the on-board GPS observations. Comparing the differences between those methods have great significance to establish the mathematical model and is usefull for us to select a suitable method to determine the orbit of the satellite. Based on the zero-difference GPS carrier-phase measurements, Shanghai Astronomical Observatory (SHAO) has improved the early version of SHORDE and then developed it as an integrated software system, which can perform the POD of LEOs by using the above three methods. In order to introduce the function of the software, we take the Gravity Recovery And Climate Experiment (GRACE) on-board GPS observations in January 2008 as example, then we compute the corresponding orbits of GRACE by using the SHORDE software. In order to evaluate the accuracy, we compare the orbits with the precise orbits provided by Jet Propulsion Laboratory (JPL). The results show that: (1) If we use the dynamic POD method, and the force models are used to represent the non-conservative forces, the average accuracy of the GRACE orbit is 2.40cm, 3.91cm, 2.34cm and 5.17cm in radial (R), along-track (T), cross-track (N) and 3D directions respectively; If we use the accelerometer observation instead of non-conservative perturbation model, the average accuracy of the orbit is 1.82cm, 2.51cm, 3.48cm and 4.68cm in R, T, N and 3D directions respectively. The result shows that if we use accelerometer observation instead of the non-conservative perturbation model, the accuracy of orbit is better. (2) When we use the reduced-dynamic POD method to get the orbits, the average accuracy of the orbit is 0.80cm, 1.36cm, 2.38cm and 2.87cm in R, T, N and 3D directions respectively. This method is carried out by setting up the pseudo-stochastic pulses to absorb the errors of atmospheric drag and other perturbations. (3) If we use the kinematic POD method, the accuracy of the GRACE orbit is 2.92cm, 2.48cm, 2.76cm and 4.75cm in R, T, N and 3D directions respectively. In conclusion, it can be seen that the POD of GRACE satellite is practicable by using different strategies and methods. The orbit solution is well and stable, they all can obtain the GRACE orbits with centimeter-level precision.
Yielding physically-interpretable emulators - A Sparse PCA approach
NASA Astrophysics Data System (ADS)
Galelli, S.; Alsahaf, A.; Giuliani, M.; Castelletti, A.
2015-12-01
Projection-based techniques, such as Principal Orthogonal Decomposition (POD), are a common approach to surrogate high-fidelity process-based models by lower order dynamic emulators. With POD, the dimensionality reduction is achieved by using observations, or 'snapshots' - generated with the high-fidelity model -, to project the entire set of input and state variables of this model onto a smaller set of basis functions that account for most of the variability in the data. While reduction efficiency and variance control of POD techniques are usually very high, the resulting emulators are structurally highly complex and can hardly be given a physically meaningful interpretation as each basis is a projection of the entire set of inputs and states. In this work, we propose a novel approach based on Sparse Principal Component Analysis (SPCA) that combines the several assets of POD methods with the potential for ex-post interpretation of the emulator structure. SPCA reduces the number of non-zero coefficients in the basis functions by identifying a sparse matrix of coefficients. While the resulting set of basis functions may retain less variance of the snapshots, the presence of a few non-zero coefficients assists in the interpretation of the underlying physical processes. The SPCA approach is tested on the reduction of a 1D hydro-ecological model (DYRESM-CAEDYM) used to describe the main ecological and hydrodynamic processes in Tono Dam, Japan. An experimental comparison against a standard POD approach shows that SPCA achieves the same accuracy in emulating a given output variable - for the same level of dimensionality reduction - while yielding better insights of the main process dynamics.
EpiPOD : community vaccination and dispensing model user's guide.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Berry, M.; Samsa, M.; Walsh, D.
EpiPOD is a modeling system that enables local, regional, and county health departments to evaluate and refine their plans for mass distribution of antiviral and antibiotic medications and vaccines. An intuitive interface requires users to input as few or as many plan specifics as are available in order to simulate a mass treatment campaign. Behind the input interface, a system dynamics model simulates pharmaceutical supply logistics, hospital and first-responder personnel treatment, population arrival dynamics and treatment, and disease spread. When the simulation is complete, users have estimates of the number of illnesses in the population at large, the number ofmore » ill persons seeking treatment, and queuing and delays within the mass treatment system--all metrics by which the plan can be judged.« less
Investigation of the Stability of POD-Galerkin Techniques for Reduced Order Model Development
2016-01-09
symmetrizing the higher- order PDE with a preconditioning matrix. Rowley et al. also pointed out that defining a proper inner product can be important when...equations. The ROM is obtained by employing Galerkin’s method to reduce the high-order PDEs to a lower-order ODE system by means of POD eigen-bases...employing Galerkin’s method to reduce the high-order PDEs to a lower-order ODE system by means of POD eigen-bases. Possible solutions of the ROM stability
USDA-ARS?s Scientific Manuscript database
Where it occurs in South and Central America, M. roreri (Mr) causes a destructive pod disease (frosty pod rot) on Theobroma cacao (cacao). Hand pollinated cacao pods were inoculated with Mr spores in the field and assessed for disease symptoms over a 90 day period. On average, pods showed symptoms o...
Model Adaptation in Parametric Space for POD-Galerkin Models
NASA Astrophysics Data System (ADS)
Gao, Haotian; Wei, Mingjun
2017-11-01
The development of low-order POD-Galerkin models is largely motivated by the expectation to use the model developed with a set of parameters at their native values to predict the dynamic behaviors of the same system under different parametric values, in other words, a successful model adaptation in parametric space. However, most of time, even small deviation of parameters from their original value may lead to large deviation or unstable results. It has been shown that adding more information (e.g. a steady state, mean value of a different unsteady state, or an entire different set of POD modes) may improve the prediction of flow with other parametric states. For a simple case of the flow passing a fixed cylinder, an orthogonal mean mode at a different Reynolds number may stabilize the POD-Galerkin model when Reynolds number is changed. For a more complicated case of the flow passing an oscillatory cylinder, a global POD-Galerkin model is first applied to handle the moving boundaries, then more information (e.g. more POD modes) is required to predicate the flow under different oscillatory frequencies. Supported by ARL.
NASA Technical Reports Server (NTRS)
Doll, C.; Mistretta, G.; Hart, R.; Oza, D.; Cox, C.; Nemesure, M.; Bolvin, D.; Samii, Mina V.
1993-01-01
Orbit determination results are obtained by the Goddard Space Flight Center (GSFC) Flight Dynamics Division (FDD) using the Goddard Trajectory Determination System (GTDS) and a real-time extended Kalman filter estimation system to process Tracking Data and Relay Satellite (TDRS) System (TDRSS) measurements in support of the Ocean Topography Experiment (TOPEX)/Poseidon spacecraft navigation and health and safety operations. GTDS is the operational orbit determination system used by the FDD, and the extended Kalman fliter was implemented in an analysis prototype system, the Real-Time Orbit Determination System/Enhanced (RTOD/E). The Precision Orbit Determination (POD) team within the GSFC Space Geodesy Branch generates an independent set of high-accuracy trajectories to support the TOPEX/Poseidon scientific data. These latter solutions use the Geodynamics (GEODYN) orbit determination system with laser ranging tracking data. The TOPEX/Poseidon trajectories were estimated for the October 22 - November 1, 1992, timeframe, for which the latest preliminary POD results were available. Independent assessments were made of the consistencies of solutions produced by the batch and sequential methods. The batch cases were assessed using overlap comparisons, while the sequential cases were assessed with covariances and the first measurement residuals. The batch least-squares and forward-filtered RTOD/E orbit solutions were compared with the definitive POD orbit solutions. The solution differences were generally less than 10 meters (m) for the batch least squares and less than 18 m for the sequential estimation solutions. The differences among the POD, GTDS, and RTOD/E solutions can be traced to differences in modeling and tracking data types, which are being analyzed in detail.
Precise Orbit Determination Of Low Earth Satellites At AIUB Using GPS And SLR Data
NASA Astrophysics Data System (ADS)
Jaggi, A.; Bock, H.; Thaller, D.; Sosnica, K.; Meyer, U.; Baumann, C.; Dach, R.
2013-12-01
An ever increasing number of low Earth orbiting (LEO) satellites is, or will be, equipped with retro-reflectors for Satellite Laser Ranging (SLR) and on-board receivers to collect observations from Global Navigation Satellite Systems (GNSS) such as the Global Positioning System (GPS) and the Russian GLONASS and the European Galileo systems in the future. At the Astronomical Institute of the University of Bern (AIUB) LEO precise orbit determination (POD) using either GPS or SLR data is performed for a wide range of applications for satellites at different altitudes. For this purpose the classical numerical integration techniques, as also used for dynamic orbit determination of satellites at high altitudes, are extended by pseudo-stochastic orbit modeling techniques to efficiently cope with potential force model deficiencies for satellites at low altitudes. Accuracies of better than 2 cm may be achieved by pseudo-stochastic orbit modeling for satellites at very low altitudes such as for the GPS-based POD of the Gravity field and steady-state Ocean Circulation Explorer (GOCE).
2008-04-26
substrate Si3N4 Diameter : 540 nm Pitch : 760 nm Diamond Holes in Diamond (HID) Pillars of Diamond (POD) POD with Electrooptic Polymer at Center 3D ...Diamond film : 2 um Si- substrate Al : 0.2 um PMMA : 0.5um 1. Deposit UNCD film 2. Deposit Al metal 3. Deposit PMMA on Al 4. E-beam Lithography 5...band-gap (PBG) based cavities. The cavities are etched directly on to the diamond substrate . The set of coupled qubits in each spot represents an
Exploration of POD-Galerkin Techniques for Developing Reduced Order Models of the Euler Equations
2015-07-01
modes [1]. Barone et al [15, 16] proposed to stabilize the reduced system by symmetrizing the higher-order PDE with a preconditioning matrix. Rowley et...advection scalar equation. The ROM is obtained by employing Galerkin’s method to reduce the high-order PDEs to a lower- order ODE system by means of POD...high-order PDEs to a lower-order ODE system by means of POD eigen-bases. For purposes of this study, a linearized version of the Euler equations is
Aeroelastic System Development Using Proper Orthogonal Decomposition and Volterra Theory
NASA Technical Reports Server (NTRS)
Lucia, David J.; Beran, Philip S.; Silva, Walter A.
2003-01-01
This research combines Volterra theory and proper orthogonal decomposition (POD) into a hybrid methodology for reduced-order modeling of aeroelastic systems. The out-come of the method is a set of linear ordinary differential equations (ODEs) describing the modal amplitudes associated with both the structural modes and the POD basis functions for the uid. For this research, the structural modes are sine waves of varying frequency, and the Volterra-POD approach is applied to the fluid dynamics equations. The structural modes are treated as forcing terms which are impulsed as part of the uid model realization. Using this approach, structural and uid operators are coupled into a single aeroelastic operator. This coupling converts a free boundary uid problem into an initial value problem, while preserving the parameter (or parameters) of interest for sensitivity analysis. The approach is applied to an elastic panel in supersonic cross ow. The hybrid Volterra-POD approach provides a low-order uid model in state-space form. The linear uid model is tightly coupled with a nonlinear panel model using an implicit integration scheme. The resulting aeroelastic model provides correct limit-cycle oscillation prediction over a wide range of panel dynamic pressure values. Time integration of the reduced-order aeroelastic model is four orders of magnitude faster than the high-order solution procedure developed for this research using traditional uid and structural solvers.
Open-Source Conceptual Sizing Models for the Hyperloop Passenger Pod
NASA Technical Reports Server (NTRS)
Chin, Jeffrey C.; Gray, Justin S.; Jones, Scott M.; Berton, Jeffrey J.
2015-01-01
Hyperloop is a new mode of transportation proposed as an alternative to California's high speed rail project, with the intended benefits of higher performance at lower overall costs. It consists of a passenger pod traveling through a tube under a light vacuum and suspended on air bearings. The pod travels up to transonic speeds resulting in a 35 minute travel time between the intended route from Los Angeles and San Francisco. Of the two variants outlined, the smaller system includes a 1.1 meter tall passenger capsule traveling through a 2.2 meter tube at 700 miles per hour. The passenger pod features water-based heat exchangers as well as an on-board compression system that reduces the aerodynamic drag as it moves through the tube. Although the original proposal looks very promising, it assumes that tube and pod dimensions are independently sizable without fully acknowledging the constraints of the compressor system on the pod geometry. This work focuses on the aerodynamic and thermodynamic interactions between the two largest systems; the tube and the pod. Using open-source toolsets, a new sizing method is developed based on one-dimensional thermodynamic relationships that accounts for the strong interactions between these sub-systems. These additional considerations require a tube nearly twice the size originally considered and limit the maximum pod travel speed to about 620 miles per hour. Although the results indicate that Hyperloop will need to be larger and slightly slower than originally intended, the estimated travel time only increases by approximately five minutes, so the overall performance is not dramatically affected. In addition, the proposed on-board heat exchanger is not an ideal solution to achieve reasonable equilibrium air temperatures within the tube. Removal of this subsystem represents a potential reduction in weight, energy requirements and complexity of the pod. In light of these finding, the core concept still remains a compelling possibility, although additional engineering and economic analyses are markedly necessary before a more complete design can be developed.
SU-E-I-79: Effect of Number of Pinholes in Onboard Robotic Multi-Pinhole SPECT System
DOE Office of Scientific and Technical Information (OSTI.GOV)
Touch, M; Bowsher, J; Yan, S
Purpose: To study the effect of number of pinholes for a novel Single Photon Emission Computed Tomography (SPECT) system for onboard molecular and functional imaging. Methods: Comparison studies were performed using simulation for the 49-pinhole SPECT system and a series of reductions in number of pinholes. Trajectories about the breast of a supine patient were considered. Minimum distances, radii of rotation (RORs), were determined by requirements to fully view the region of interest (ROI) and to avoid collision between the detector and the patient. Reductions in RORs translate into improvements in sensitivity. Starting from the 49-pinhole system, pinholes were removedmore » pod by pod. The furthest two end pods in the Sup-Inf direction were removed first for their higher likelihood of alleviating the collision avoidance criteria. After iterating through different combinations of pinhole pods, and selecting three combinations, the corresponding RORs were used to analytically calculate sensitivities. Results: Based on the Methods procedure, 3 combination of pods removal were identified: 1) Superior peripheral pod 2) Inferior peripheral pod 3) both pods. RORs were reduced at only one multi-pinhole stop. Analytic calculation showed that sensitivities were reduced from 0.032 for the 49-pinhole system to 0.028 for 42-pinhole and to 0.023 for 39-pinhole system respectively. The sensitivity per pinhole detector was approximately the same for all three cases. Conclusion: For the trajectories considered, only minimal improvements in RORs were identified by removing pinhole pods. Consequently, sensitivities decreased in proportion to the number of pinholes. Studies of other anatomical sites are needed to determine if in some cases sensitivity per pinhole can be improved by removing some pinholes. PHS/NIH/NCI grant R21-CA156390-01A1.« less
NASA Astrophysics Data System (ADS)
Gosses, Moritz; Nowak, Wolfgang; Wöhling, Thomas
2018-05-01
In recent years, proper orthogonal decomposition (POD) has become a popular model reduction method in the field of groundwater modeling. It is used to mitigate the problem of long run times that are often associated with physically-based modeling of natural systems, especially for parameter estimation and uncertainty analysis. POD-based techniques reproduce groundwater head fields sufficiently accurate for a variety of applications. However, no study has investigated how POD techniques affect the accuracy of different boundary conditions found in groundwater models. We show that the current treatment of boundary conditions in POD causes inaccuracies for these boundaries in the reduced models. We provide an improved method that splits the POD projection space into a subspace orthogonal to the boundary conditions and a separate subspace that enforces the boundary conditions. To test the method for Dirichlet, Neumann and Cauchy boundary conditions, four simple transient 1D-groundwater models, as well as a more complex 3D model, are set up and reduced both by standard POD and POD with the new extension. We show that, in contrast to standard POD, the new method satisfies both Dirichlet and Neumann boundary conditions. It can also be applied to Cauchy boundaries, where the flux error of standard POD is reduced by its head-independent contribution. The extension essentially shifts the focus of the projection towards the boundary conditions. Therefore, we see a slight trade-off between errors at model boundaries and overall accuracy of the reduced model. The proposed POD extension is recommended where exact treatment of boundary conditions is required.
Structural health monitoring and probability of detection estimation
NASA Astrophysics Data System (ADS)
Forsyth, David S.
2016-02-01
Structural health monitoring (SHM) methods are often based on nondestructive testing (NDT) sensors and are often proposed as replacements for NDT to lower cost and/or improve reliability. In order to take advantage of SHM for life cycle management, it is necessary to determine the Probability of Detection (POD) of the SHM system just as for traditional NDT to ensure that the required level of safety is maintained. Many different possibilities exist for SHM systems, but one of the attractive features of SHM versus NDT is the ability to take measurements very simply after the SHM system is installed. Using a simple statistical model of POD, some authors have proposed that very high rates of SHM system data sampling can result in high effective POD even in situations where an individual test has low POD. In this paper, we discuss the theoretical basis for determining the effect of repeated inspections, and examine data from SHM experiments against this framework to show how the effective POD from multiple tests can be estimated.
Shah, A A; Xing, W W; Triantafyllidis, V
2017-04-01
In this paper, we develop reduced-order models for dynamic, parameter-dependent, linear and nonlinear partial differential equations using proper orthogonal decomposition (POD). The main challenges are to accurately and efficiently approximate the POD bases for new parameter values and, in the case of nonlinear problems, to efficiently handle the nonlinear terms. We use a Bayesian nonlinear regression approach to learn the snapshots of the solutions and the nonlinearities for new parameter values. Computational efficiency is ensured by using manifold learning to perform the emulation in a low-dimensional space. The accuracy of the method is demonstrated on a linear and a nonlinear example, with comparisons with a global basis approach.
Xing, W. W.; Triantafyllidis, V.
2017-01-01
In this paper, we develop reduced-order models for dynamic, parameter-dependent, linear and nonlinear partial differential equations using proper orthogonal decomposition (POD). The main challenges are to accurately and efficiently approximate the POD bases for new parameter values and, in the case of nonlinear problems, to efficiently handle the nonlinear terms. We use a Bayesian nonlinear regression approach to learn the snapshots of the solutions and the nonlinearities for new parameter values. Computational efficiency is ensured by using manifold learning to perform the emulation in a low-dimensional space. The accuracy of the method is demonstrated on a linear and a nonlinear example, with comparisons with a global basis approach. PMID:28484327
Autonomous collection of dynamically-cued multi-sensor imagery
NASA Astrophysics Data System (ADS)
Daniel, Brian; Wilson, Michael L.; Edelberg, Jason; Jensen, Mark; Johnson, Troy; Anderson, Scott
2011-05-01
The availability of imagery simultaneously collected from sensors of disparate modalities enhances an image analyst's situational awareness and expands the overall detection capability to a larger array of target classes. Dynamic cooperation between sensors is increasingly important for the collection of coincident data from multiple sensors either on the same or on different platforms suitable for UAV deployment. Of particular interest is autonomous collaboration between wide area survey detection, high-resolution inspection, and RF sensors that span large segments of the electromagnetic spectrum. The Naval Research Laboratory (NRL) in conjunction with the Space Dynamics Laboratory (SDL) is building sensors with such networked communications capability and is conducting field tests to demonstrate the feasibility of collaborative sensor data collection and exploitation. Example survey / detection sensors include: NuSAR (NRL Unmanned SAR), a UAV compatible synthetic aperture radar system; microHSI, an NRL developed lightweight hyper-spectral imager; RASAR (Real-time Autonomous SAR), a lightweight podded synthetic aperture radar; and N-WAPSS-16 (Nighttime Wide-Area Persistent Surveillance Sensor-16Mpix), a MWIR large array gimbaled system. From these sensors, detected target cues are automatically sent to the NRL/SDL developed EyePod, a high-resolution, narrow FOV EO/IR sensor, for target inspection. In addition to this cooperative data collection, EyePod's real-time, autonomous target tracking capabilities will be demonstrated. Preliminary results and target analysis will be presented.
NASA Astrophysics Data System (ADS)
Gosses, Moritz; Nowak, Wolfgang; Wöhling, Thomas
2017-04-01
Physically-based modeling is a wide-spread tool in understanding and management of natural systems. With the high complexity of many such models and the huge amount of model runs necessary for parameter estimation and uncertainty analysis, overall run times can be prohibitively long even on modern computer systems. An encouraging strategy to tackle this problem are model reduction methods. In this contribution, we compare different proper orthogonal decomposition (POD, Siade et al. (2010)) methods and their potential applications to groundwater models. The POD method performs a singular value decomposition on system states as simulated by the complex (e.g., PDE-based) groundwater model taken at several time-steps, so-called snapshots. The singular vectors with the highest information content resulting from this decomposition are then used as a basis for projection of the system of model equations onto a subspace of much lower dimensionality than the original complex model, thereby greatly reducing complexity and accelerating run times. In its original form, this method is only applicable to linear problems. Many real-world groundwater models are non-linear, tough. These non-linearities are introduced either through model structure (unconfined aquifers) or boundary conditions (certain Cauchy boundaries, like rivers with variable connection to the groundwater table). To date, applications of POD focused on groundwater models simulating pumping tests in confined aquifers with constant head boundaries. In contrast, POD model reduction either greatly looses accuracy or does not significantly reduce model run time if the above-mentioned non-linearities are introduced. We have also found that variable Dirichlet boundaries are problematic for POD model reduction. An extension to the POD method, called POD-DEIM, has been developed for non-linear groundwater models by Stanko et al. (2016). This method uses spatial interpolation points to build the equation system in the reduced model space, thereby allowing the recalculation of system matrices at every time-step necessary for non-linear models while retaining the speed of the reduced model. This makes POD-DEIM applicable for groundwater models simulating unconfined aquifers. However, in our analysis, the method struggled to reproduce variable river boundaries accurately and gave no advantage for variable Dirichlet boundaries compared to the original POD method. We have developed another extension for POD that targets to address these remaining problems by performing a second POD operation on the model matrix on the left-hand side of the equation. The method aims to at least reproduce the accuracy of the other methods where they are applicable while outperforming them for setups with changing river boundaries or variable Dirichlet boundaries. We compared the new extension with original POD and POD-DEIM for different combinations of model structures and boundary conditions. The new method shows the potential of POD extensions for applications to non-linear groundwater systems and complex boundary conditions that go beyond the current, relatively limited range of applications. References: Siade, A. J., Putti, M., and Yeh, W. W.-G. (2010). Snapshot selection for groundwater model reduction using proper orthogonal decomposition. Water Resour. Res., 46(8):W08539. Stanko, Z. P., Boyce, S. E., and Yeh, W. W.-G. (2016). Nonlinear model reduction of unconfined groundwater flow using pod and deim. Advances in Water Resources, 97:130 - 143.
Reduced-Order Models Based on POD-Tpwl for Compositional Subsurface Flow Simulation
NASA Astrophysics Data System (ADS)
Durlofsky, L. J.; He, J.; Jin, L. Z.
2014-12-01
A reduced-order modeling procedure applicable for compositional subsurface flow simulation will be described and applied. The technique combines trajectory piecewise linearization (TPWL) and proper orthogonal decomposition (POD) to provide highly efficient surrogate models. The method is based on a molar formulation (which uses pressure and overall component mole fractions as the primary variables) and is applicable for two-phase, multicomponent systems. The POD-TPWL procedure expresses new solutions in terms of linearizations around solution states generated and saved during previously simulated 'training' runs. High-dimensional states are projected into a low-dimensional subspace using POD. Thus, at each time step, only a low-dimensional linear system needs to be solved. Results will be presented for heterogeneous three-dimensional simulation models involving CO2 injection. Both enhanced oil recovery and carbon storage applications (with horizontal CO2 injectors) will be considered. Reasonably close agreement between full-order reference solutions and compositional POD-TPWL simulations will be demonstrated for 'test' runs in which the well controls differ from those used for training. Construction of the POD-TPWL model requires preprocessing overhead computations equivalent to about 3-4 full-order runs. Runtime speedups using POD-TPWL are, however, very significant - typically O(100-1000). The use of POD-TPWL for well control optimization will also be illustrated. For this application, some amount of retraining during the course of the optimization is required, which leads to smaller, but still significant, speedup factors.
NASA Astrophysics Data System (ADS)
Le Bel, D. A.; Brown, S.; Zappa, C. J.; Bell, R. E.; Frearson, N.; Tinto, K. J.
2014-12-01
Photogrammetric digital elevation models (DEMs) are a powerful approach for understanding elevation change and dynamics along the margins of the large ice sheets. The IcePod system, mounted on a New York Air National Guard LC-130, can measure high-resolution surface elevations with a Riegl VQ580 scanning laser altimeter and Imperx Bobcat IGV-B6620 color visible-wavelength camera (6600x4400 resolution); the surface temperature with a Sofradir IRE-640L infrared camera (spectral response 7.7-9.5 μm, 640x512 resolution); and the structure of snow and ice with two radar systems. We show the use of IcePod imagery to develop DEMs across calving fronts and meltwater channels in Greenland. Multiple over-flights of the Kangerlussaq Airport ramp have provided a test of the technique at a location with accurate, independently-determined elevation. Here the photogrammetric DEM of the airport, constrained by ground control measurements, is compared with the Lidar results. In July 2014 the IcePod ice-ocean imaging system surveyed the calving fronts of five outlet glaciers north of Jakobshavn Isbrae. We used Agisoft PhotoScan to develop a DEM of each calving front using imagery captured by the IcePod systems. Adjacent to the ice sheet, meltwater plumes foster mixing in the fjord, moving warm ocean water into contact with the front of the ice sheet where it can undercut the ice front and trigger calving. The five glaciers provide an opportunity to examine the calving front structure in relation to ocean temperature, fjord circulation, and spatial scale of the meltwater plumes. The combination of the accurate DEM of the calving front and the thermal imagery used to constrain the temperature and dynamics of the adjacent plume provides new insights into the ice-ocean interactions. Ice sheet margins provide insights into the connections between the surface meltwater and the fate of the water at the ice sheet base. Surface meltwater channels are visualized here for the first time using the combination of Lidar, photogrammetry DEMs and infrared imagery. These techniques leverage electromagnetic surface properties that allow us to identify the presence of water, measure the slope and elevation of the channel, as well as the two-dimensional temperature variability of the water/ice/snow in multiple melt channels within a drainage system.
DUSTER: demonstration of an integrated LWIR-VNIR-SAR imaging system
NASA Astrophysics Data System (ADS)
Wilson, Michael L.; Linne von Berg, Dale; Kruer, Melvin; Holt, Niel; Anderson, Scott A.; Long, David G.; Margulis, Yuly
2008-04-01
The Naval Research Laboratory (NRL) and Space Dynamics Laboratory (SDL) are executing a joint effort, DUSTER (Deployable Unmanned System for Targeting, Exploitation, and Reconnaissance), to develop and test a new tactical sensor system specifically designed for Tier II UAVs. The system is composed of two coupled near-real-time sensors: EyePod (VNIR/LWIR ball gimbal) and NuSAR (L-band synthetic aperture radar). EyePod consists of a jitter-stabilized LWIR sensor coupled with a dual focal-length optical system and a bore-sighted high-resolution VNIR sensor. The dual focal-length design coupled with precision pointing an step-stare capabilities enable EyePod to conduct wide-area survey and high resolution inspection missions from a single flight pass. NuSAR is being developed with partners Brigham Young University (BYU) and Artemis, Inc and consists of a wideband L-band SAR capable of large area survey and embedded real-time image formation. Both sensors employ standard Ethernet interfaces and provide geo-registered NITFS output imagery. In the fall of 2007, field tests were conducted with both sensors, results of which will be presented.
Deconvolution of reacting-flow dynamics using proper orthogonal and dynamic mode decompositions
NASA Astrophysics Data System (ADS)
Roy, Sukesh; Hua, Jia-Chen; Barnhill, Will; Gunaratne, Gemunu H.; Gord, James R.
2015-01-01
Analytical and computational studies of reacting flows are extremely challenging due in part to nonlinearities of the underlying system of equations and long-range coupling mediated by heat and pressure fluctuations. However, many dynamical features of the flow can be inferred through low-order models if the flow constituents (e.g., eddies or vortices) and their symmetries, as well as the interactions among constituents, are established. Modal decompositions of high-frequency, high-resolution imaging, such as measurements of species-concentration fields through planar laser-induced florescence and of velocity fields through particle-image velocimetry, are the first step in the process. A methodology is introduced for deducing the flow constituents and their dynamics following modal decomposition. Proper orthogonal (POD) and dynamic mode (DMD) decompositions of two classes of problems are performed and their strengths compared. The first problem involves a cellular state generated in a flat circular flame front through symmetry breaking. The state contains two rings of cells that rotate clockwise at different rates. Both POD and DMD can be used to deconvolve the state into the two rings. In POD the contribution of each mode to the flow is quantified using the energy. Each DMD mode can be associated with an energy as well as a unique complex growth rate. Dynamic modes with the same spatial symmetry but different growth rates are found to be combined into a single POD mode. Thus, a flow can be approximated by a smaller number of POD modes. On the other hand, DMD provides a more detailed resolution of the dynamics. Two classes of reacting flows behind symmetric bluff bodies are also analyzed. In the first, symmetric pairs of vortices are released periodically from the two ends of the bluff body. The second flow contains von Karman vortices also, with a vortex being shed from one end of the bluff body followed by a second shedding from the opposite end. The way in which DMD can be used to deconvolve the second flow into symmetric and von Karman vortices is demonstrated. The analyses performed illustrate two distinct advantages of DMD: (1) Unlike proper orthogonal modes, each dynamic mode is associated with a unique complex growth rate. By comparing DMD spectra from multiple nominally identical experiments, it is possible to identify "reproducible" modes in a flow. We also find that although most high-energy modes are reproducible, some are not common between experimental realizations; in the examples considered, energy fails to differentiate between reproducible and nonreproducible modes. Consequently, it may not be possible to differentiate reproducible and nonreproducible modes in POD. (2) Time-dependent coefficients of dynamic modes are complex. Even in noisy experimental data, the dynamics of the phase of these coefficients (but not their magnitude) are highly regular. The phase represents the angular position of a rotating ring of cells and quantifies the downstream displacement of vortices in reacting flows. Thus, it is suggested that the dynamical characterizations of complex flows are best made through the phase dynamics of reproducible DMD modes.
Reduced-order modeling of the flow around a high-lift configuration with unsteady Coanda blowing
NASA Astrophysics Data System (ADS)
Semaan, Richard; Cordier, Laurent; Noack, Bernd; Kumar, Pradeep; Burnazzi, Marco; Tissot, Gilles
2015-11-01
We propose a low-dimensional POD model for the transient and post-transient flow around a high-lift airfoil with unsteady Coanda blowing over the trailing edge. This model comprises the effect of high-frequency modulated blowing which mitigates vortex shedding and increases lift. The structure of the dynamical system is derived from the Navier-Stokes equations with a Galerkin projection and from subsequent dynamic simplifications. The system parameters are determined with a data assimilation (4D-Var) method. The boundary actuation is incorporated into the model with actuation modes following Graham et al. (1999); Kasnakoğlu et al. (2008). As novel enabler, we show that the performance of the POD model significantly benefits from employing additional actuation modes for different frequency components associated with the same actuation input. In addition, linear, weakly nonlinear and fully nonlinear models are considered. The current study suggests that separate actuation modes for different actuation frequencies improve Galerkin model performance, in particular with respect to the important base-flow changes. We acknowledge (1) the Collaborative Research Centre (CRC 880) ``Fundamentals of High Lift of Future Civil Aircraft,'' and 2) the Senior Chair of Excellence ``Closed-loop control of turbulent shear flows using reduced-order models'' (TUCOROM).
NASA Astrophysics Data System (ADS)
Kim, Young-Rok; Park, Eunseo; Choi, Eun-Jung; Park, Sang-Young; Park, Chandeok; Lim, Hyung-Chul
2014-09-01
In this study, genetic resampling (GRS) approach is utilized for precise orbit determination (POD) using the batch filter based on particle filtering (PF). Two genetic operations, which are arithmetic crossover and residual mutation, are used for GRS of the batch filter based on PF (PF batch filter). For POD, Laser-ranging Precise Orbit Determination System (LPODS) and satellite laser ranging (SLR) observations of the CHAMP satellite are used. Monte Carlo trials for POD are performed by one hundred times. The characteristics of the POD results by PF batch filter with GRS are compared with those of a PF batch filter with minimum residual resampling (MRRS). The post-fit residual, 3D error by external orbit comparison, and POD repeatability are analyzed for orbit quality assessments. The POD results are externally checked by NASA JPL’s orbits using totally different software, measurements, and techniques. For post-fit residuals and 3D errors, both MRRS and GRS give accurate estimation results whose mean root mean square (RMS) values are at a level of 5 cm and 10-13 cm, respectively. The mean radial orbit errors of both methods are at a level of 5 cm. For POD repeatability represented as the standard deviations of post-fit residuals and 3D errors by repetitive PODs, however, GRS yields 25% and 13% more robust estimation results than MRRS for post-fit residual and 3D error, respectively. This study shows that PF batch filter with GRS approach using genetic operations is superior to PF batch filter with MRRS in terms of robustness in POD with SLR observations.
Developing an Accurate CFD Based Gust Model for the Truss Braced Wing Aircraft
NASA Technical Reports Server (NTRS)
Bartels, Robert E.
2013-01-01
The increased flexibility of long endurance aircraft having high aspect ratio wings necessitates attention to gust response and perhaps the incorporation of gust load alleviation. The design of civil transport aircraft with a strut or truss-braced high aspect ratio wing furthermore requires gust response analysis in the transonic cruise range. This requirement motivates the use of high fidelity nonlinear computational fluid dynamics (CFD) for gust response analysis. This paper presents the development of a CFD based gust model for the truss braced wing aircraft. A sharp-edged gust provides the gust system identification. The result of the system identification is several thousand time steps of instantaneous pressure coefficients over the entire vehicle. This data is filtered and downsampled to provide the snapshot data set from which a reduced order model is developed. A stochastic singular value decomposition algorithm is used to obtain a proper orthogonal decomposition (POD). The POD model is combined with a convolution integral to predict the time varying pressure coefficient distribution due to a novel gust profile. Finally the unsteady surface pressure response of the truss braced wing vehicle to a one-minus-cosine gust, simulated using the reduced order model, is compared with the full CFD.
Fundamental Insights into Combustion Instability Predictions in Aerospace Propulsion
NASA Astrophysics Data System (ADS)
Huang, Cheng
Integrated multi-fidelity modeling has been performed for combustion instability in aerospace propulsion, which includes two levels of analysis: first, computational fluid dynamics (CFD) using hybrid RANS/LES simulations for underlying physics investigations (high-fidelity modeling); second, modal decomposition techniques for diagnostics (analysis & validation); third, development of flame response model using model reduction techniques for practical design applications (low-order model). For the high-fidelity modeling, the relevant CFD code development work is moving towards combustion instability prediction for liquid propulsion system. A laboratory-scale single-element lean direct injection (LDI) gas turbine combustor is used for configuration that produces self-excited combustion instability. The model gas turbine combustor is featured with an air inlet section, air plenum, swirler-venturi-injector assembly, combustion chamber, and exit nozzle. The combustor uses liquid fuel (Jet-A/FT-SPK) and heated air up to 800K. Combustion dynamics investigations are performed with the same geometry and operating conditions concurrently between the experiment and computation at both high (φ=0.6) and low (φ=0.36) equivalence ratios. The simulation is able to reach reasonable agreement with experiment measurements in terms of the pressure signal. Computational analyses are also performed using an acoustically-open geometry to investigate the characteristic hydrodynamics in the combustor with both constant and perturbed inlet mass flow rates. Two hydrodynamic modes are identified by using Dynamic Mode Decomposition (DMD) analysis: Vortex Breakdown Bubble (VBB) and swirling modes. Following that, the closed geometry simulation results are analyzed in three steps. In step one, a detailed cycle analysis shows two physically important couplings in the combustor: first, the acoustic compression enhances the spray drop breakup and vaporization, and generates more gaseous fuel for reaction; second, the acoustic compression couples with the unsteady hydrodynamics found in the open-geometry simulation, enhances the fuel/air mixing, and triggers a large amount of heat addition. In step two, a modal analysis using DMD extracts the dynamic features of important modes in the combustor, and identifies the presence of Precessing Vortex Core (PVC) mode and its nonlinear interactions with acoustic modes. Moreover, the DMD analysis helps to establish the couplings between the hydrodynamics and acoustics in terms of frequencies. In step 3, Rayleigh index analysis provides a quantitative assessment of acoustics/combustion couplings and identifies local regions for instability driving/damping. Two modal decomposition techniques, Proper Orthogonal Decomposition (POD) and Dynamic Mode Decomposition (DMD), are assessed in terms of their capabilities in extracting important information from the original simulation dataset and in validating the computational results using the experiment measurement. A POD analysis provides a series of modes with decreasing energy content and it offers an efficient and optimized way to represent a large dataset. The frequency-based DMD technique provides modes that correspond to all single frequencies. For the low-order modeling, fundamental aspects are examined to study necessary conditions, criteria and approaches to develop a reduced-order model (ROM) that is able to represent generic combustion/flame responses, which then can be used in an engineering level tool to provide efficient predictions of combustion instability for practical design applications. Explorations are focused on model reduction techniques by using the so-called POD/Galerkin method. The method uses the numerical solutions of the model equations as the database for building a set of POD eigen-bases. Specifically, the numerical solutions are calculated by perturbing quantities of interest such as the inlet conditions. The POD-derived eigen-bases are, in turn, used in conjunction with a Galerkin procedure to reduce the governing partial differential equation to an ordinary differential equation, which constitutes the ROM. Once the ROM is established, it can then be used as a lower-order test-bed to predict detailed results within certain parametric ranges at a fraction of the cost of solving the full governing equations. A detailed assessment is performed on the method in two parts. In part one, a one-dimensional scalar reaction-advection model equation is used for fundamental investigations, which include verification of the POD eigen-basis calculation and of the ROM development procedure. Moreover, certain criteria during ROM development are established: 1. a necessary number of POD modes that should be included to guarantee a stable ROM; 2. the need for the numerical discretization scheme to be consistent between the original CFD and the developed ROM. Furthermore, the predictive capabilities of the resulting ROM are evaluated to test its limits and to validate the values of applying broadband forcing in improving the ROM performance. In part two, the exploration is extended to a vector system of equations. Using the one-dimensional Euler equation is used as a model equation. A numerical stability issue is identified during the ROM development, the cause of which is further studied and attributed to the normalization methods implemented to generate coupled POD eigen-bases for vector variables. (Abstract shortened by UMI.).
Simulation and optimization of pressure swing adsorption systmes using reduced-order modeling
DOE Office of Scientific and Technical Information (OSTI.GOV)
Agarwal, A.; Biegler, L.; Zitney, S.
2009-01-01
Over the past three decades, pressure swing adsorption (PSA) processes have been widely used as energyefficient gas separation techniques, especially for high purity hydrogen purification from refinery gases. Models for PSA processes are multiple instances of partial differential equations (PDEs) in time and space with periodic boundary conditions that link the processing steps together. The solution of this coupled stiff PDE system is governed by steep fronts moving with time. As a result, the optimization of such systems represents a significant computational challenge to current differential algebraic equation (DAE) optimization techniques and nonlinear programming algorithms. Model reduction is one approachmore » to generate cost-efficient low-order models which can be used as surrogate models in the optimization problems. This study develops a reducedorder model (ROM) based on proper orthogonal decomposition (POD), which is a low-dimensional approximation to a dynamic PDE-based model. The proposed method leads to a DAE system of significantly lower order, thus replacing the one obtained from spatial discretization and making the optimization problem computationally efficient. The method has been applied to the dynamic coupled PDE-based model of a twobed four-step PSA process for separation of hydrogen from methane. Separate ROMs have been developed for each operating step with different POD modes for each of them. A significant reduction in the order of the number of states has been achieved. The reduced-order model has been successfully used to maximize hydrogen recovery by manipulating operating pressures, step times and feed and regeneration velocities, while meeting product purity and tight bounds on these parameters. Current results indicate the proposed ROM methodology as a promising surrogate modeling technique for cost-effective optimization purposes.« less
Field-design optimization with triangular heliostat pods
NASA Astrophysics Data System (ADS)
Domínguez-Bravo, Carmen-Ana; Bode, Sebastian-James; Heiming, Gregor; Richter, Pascal; Carrizosa, Emilio; Fernández-Cara, Enrique; Frank, Martin; Gauché, Paul
2016-05-01
In this paper the optimization of a heliostat field with triangular heliostat pods is addressed. The use of structures which allow the combination of several heliostats into a common pod system aims to reduce the high costs associated with the heliostat field and therefore reduces the Levelized Cost of Electricity value. A pattern-based algorithm and two pattern-free algorithms are adapted to handle the field layout problem with triangular heliostat pods. Under the Helio100 project in South Africa, a new small-scale Solar Power Tower plant has been recently constructed. The Helio100 plant has 20 triangular pods (each with 6 heliostats) whose positions follow a linear pattern. The obtained field layouts after optimization are compared against the reference field Helio100.
An Evaluation of the Pea Pod System for Assessing Body Composition of Moderately Premature Infants.
Forsum, Elisabet; Olhager, Elisabeth; Törnqvist, Caroline
2016-04-22
(1) BACKGROUND: Assessing the quality of growth in premature infants is important in order to be able to provide them with optimal nutrition. The Pea Pod device, based on air displacement plethysmography, is able to assess body composition of infants. However, this method has not been sufficiently evaluated in premature infants; (2) METHODS: In 14 infants in an age range of 3-7 days, born after 32-35 completed weeks of gestation, body weight, body volume, fat-free mass density (predicted by the Pea Pod software), and total body water (isotope dilution) were assessed. Reference estimates of fat-free mass density and body composition were obtained using a three-component model; (3) RESULTS: Fat-free mass density values, predicted using Pea Pod, were biased but not significantly (p > 0.05) different from reference estimates. Body fat (%), assessed using Pea Pod, was not significantly different from reference estimates. The biological variability of fat-free mass density was 0.55% of the average value (1.0627 g/mL); (4) CONCLUSION: The results indicate that the Pea Pod system is accurate for groups of newborn, moderately premature infants. However, more studies where this system is used for premature infants are needed, and we provide suggestions regarding how to develop this area.
2003-09-05
KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, one of two orbital maneuvering system (OMS) pods removed from Endeavour is lowered toward a transporter. The OMS pods are attached to the upper aft fuselage left and right sides. Fabricated primarily of graphite epoxy composite and aluminum, each pod is 21.8 feet long and 11.37 feet wide at its aft end and 8.41 feet wide at its forward end, with a surface area of approximately 435 square feet. Each pod houses the Reaction Control System propulsion components used for inflight maneuvering and is attached to the aft fuselage with 11 bolts. OMS pods are removed during Orbiter Major Modifications. Once removed, the OMS pods undergo in-depth structural inspections, system checks and the thrusters are changed out.
2003-09-05
KENNEDY SPACE CENTER, FLA. - Technicians in the Orbiter Processing Facility oversee removal of one of two orbital maneuvering system (OMS) pods from Endeavour. The OMS pods are attached to the upper aft fuselage left and right sides. Fabricated primarily of graphite epoxy composite and aluminum, each pod is 21.8 feet long and 11.37 feet wide at its aft end and 8.41 feet wide at its forward end, with a surface area of approximately 435 square feet. Each pod houses the Reaction Control System propulsion components used for inflight maneuvering and is attached to the aft fuselage with 11 bolts. OMS pods are removed during Orbiter Major Modifications. Once removed, the OMS pods undergo in-depth structural inspections, system checks and the thrusters are changed out.
2003-09-05
KENNEDY SPACE CENTER, FLA. - Workers in the Orbiter Processing Facility prepare to remove one of two orbital maneuvering system (OMS) pods from Endeavour. The OMS pods are attached to the upper aft fuselage left and right sides. Fabricated primarily of graphite epoxy composite and aluminum, each pod is 21.8 feet long and 11.37 feet wide at its aft end and 8.41 feet wide at its forward end, with a surface area of approximately 435 square feet. Each pod houses the Reaction Control System propulsion components used for inflight maneuvering and is attached to the aft fuselage with 11 bolts. OMS pods are removed during Orbiter Major Modifications. Once removed, the OMS pods undergo in-depth structural inspections, system checks and the thrusters are changed out.
2003-09-05
KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, one of two orbital maneuvering system (OMS) pods removed from Endeavour is suspended overhead. The OMS pods are attached to the upper aft fuselage left and right sides. Fabricated primarily of graphite epoxy composite and aluminum, each pod is 21.8 feet long and 11.37 feet wide at its aft end and 8.41 feet wide at its forward end, with a surface area of approximately 435 square feet. Each pod houses the Reaction Control System propulsion components used for inflight maneuvering and is attached to the aft fuselage with 11 bolts. OMS pods are removed during Orbiter Major Modifications. Once removed, the OMS pods undergo in-depth structural inspections, system checks and the thrusters are changed out.
2003-09-05
KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, one of two orbital maneuvering system (OMS) pods removed from Endeavour is lowered onto a transporter. The OMS pods are attached to the upper aft fuselage left and right sides. Fabricated primarily of graphite epoxy composite and aluminum, each pod is 21.8 feet long and 11.37 feet wide at its aft end and 8.41 feet wide at its forward end, with a surface area of approximately 435 square feet. Each pod houses the Reaction Control System propulsion components used for inflight maneuvering and is attached to the aft fuselage with 11 bolts. OMS pods are removed during Orbiter Major Modifications. Once removed, the OMS pods undergo in-depth structural inspections, system checks and the thrusters are changed out.
NASA Astrophysics Data System (ADS)
Hong-bo, Wang; Chang-yin, Zhao; Wei, Zhang; Jin-wei, Zhan; Sheng-xian, Yu
2016-07-01
The Earth gravitational field model is one of the most important dynamic models in satellite orbit computation. Several space gravity missions made great successes in recent years, prompting the publishing of several gravitational filed models. In this paper, two classical (JGM3, EGM96) and four latest (EIGEN-CHAMP05S, GGM03S, GOCE02S, EGM2008) models are evaluated by employing them in the precision orbit determination (POD) and prediction. These calculations are performed based on the laser ranging observation of four Low Earth Orbit (LEO) satellites, including CHAMP, GFZ-1, GRACE-A, and SWARM-A. The residual error of observation in POD is adopted to describe the accuracy of six gravitational field models. The main results we obtained are as follows. (1) For the POD of LEOs, the accuracies of 4 latest models are at the same level, and better than those of 2 classical models; (2) Taking JGM3 as reference, EGM96 model's accuracy is better in most situations, and the accuracies of the 4 latest models are improved by 12%-47% in POD and 63% in prediction, respectively. We also confirm that the model's accuracy in POD is enhanced with the increasing degree and order if they are smaller than 70, and when they exceed 70, the accuracy keeps constant, implying that the model's degree and order truncated to 70 are sufficient to meet the requirement of LEO computation of centimeter precision.
Twisted Savonius turbine based marine current energy conversion system
NASA Astrophysics Data System (ADS)
Hassan, Md. Imtiaj
The Ocean Network Seafloor Instrumentation (ONSFI) Project is a multidisciplinary research and development project that aims to design, fabricate and validate a proof-of-concept seafloor array of wireless marine sensors for use in monitoring seabed processes. The sensor pods, known as Seaformatics, will be powered by ocean bottom currents and will be able to communicate with each other and to the Internet through surface master units to facilitate observation of the ocean floor from the shore. This thesis explores the use of the twisted Savonius turbine as a means of converting the kinetic energy of the free flowing water into electrical energy for the pods. This will eliminate the need for battery replacement. A physical model of the turbine was constructed and tested in the Water Flume at the Marine Institute of Memorial University and in the Wind Tunnel in the Engineering Building at Memorial University. A mathematical model of the turbine was constructed in SolidWorks. This was tested in the Computational Fluid Dynamics or CFD software FLOW-3D. Experimental results were compared with CFD results and the agreement was reasonable. A twisted Savonius turbine emulator was developed to test a dc-dc boost converter. A low cost microcontroller based MPPT algorithm was developed to obtain maximum power from the turbine. Overall the thesis shows that the twisted Savonius turbine can provide the power needed by the sensor pods. It also shows that CFD is a viable way to study the performance of the Savonius type of turbine.
NASA Technical Reports Server (NTRS)
2010-01-01
Topics covered include: Software Tool Integrating Data Flow Diagrams and Petri Nets; Adaptive Nulling for Interferometric Detection of Planets; Reducing the Volume of NASA Earth-Science Data; Reception of Multiple Telemetry Signals via One Dish Antenna; Space-Qualified Traveling-Wave Tube; Smart Power Supply for Battery-Powered Systems; Parallel Processing of Broad-Band PPM Signals; Inexpensive Implementation of Many Strain Gauges; Constant-Differential-Pressure Two-Fluid Accumulator; Inflatable Tubular Structures Rigidized with Foams; Power Generator with Thermo-Differential Modules; Mechanical Extraction of Power From Ocean Currents and Tides; Nitrous Oxide/Paraffin Hybrid Rocket Engines; Optimized Li-Ion Electrolytes Containing Fluorinated Ester Co-Solvents; Probabilistic Multi-Factor Interaction Model for Complex Material Behavior; Foldable Instrumented Bits for Ultrasonic/Sonic Penetrators; Compact Rare Earth Emitter Hollow Cathode; High-Precision Shape Control of In-Space Deployable Large Membrane/Thin-Shell Reflectors; Rapid Active Sampling Package; Miniature Lightweight Ion Pump; Cryogenic Transport of High-Pressure-System Recharge Gas; Water-Vapor Raman Lidar System Reaches Higher Altitude; Compact Ku-Band T/R Module for High-Resolution Radar Imaging of Cold Land Processes; Wide-Field-of-View, High-Resolution, Stereoscopic Imager; Electrical Capacitance Volume Tomography with High-Contrast Dielectrics; Wavefront Control and Image Restoration with Less Computing; Polarization Imaging Apparatus; Stereoscopic Machine-Vision System Using Projected Circles; Metal Vapor Arcing Risk Assessment Tool; Performance Bounds on Two Concatenated, Interleaved Codes; Parameterizing Coefficients of a POD-Based Dynamical System; Confidence-Based Feature Acquisition; Algorithm for Lossless Compression of Calibrated Hyperspectral Imagery; Universal Decoder for PPM of any Order; Algorithm for Stabilizing a POD-Based Dynamical System; Mission Reliability Estimation for Repairable Robot Teams; Processing AIRS Scientific Data Through Level 3; Web-Based Requesting and Scheduling Use of Facilities; AutoGen Version 5.0; Time-Tag Generation Script; PPM Receiver Implemented in Software; Tropospheric Emission Spectrometer Product File Readers; Reporting Differences Between Spacecraft Sequence Files; Coordinating "Execute" Data for ISS and Space Shuttle; Database for Safety-Oriented Tracking of Chemicals; Apparatus for Cold, Pressurized Biogeochemical Experiments; Growing B Lymphocytes in a Three-Dimensional Culture System; Tissue-like 3D Assemblies of Human Broncho-Epithelial Cells; Isolation of Resistance-Bearing Microorganisms; Oscillating Cell Culture Bioreactor; and Liquid Cooling/Warming Garment.
Schlieren optics for leak detection
NASA Technical Reports Server (NTRS)
Peale, Robert E.; Ruffin, Alranzo B.
1995-01-01
The purpose of this research was to develop an optical method of leak detection. Various modifications of schlieren optics were explored with initial emphasis on leak detection of the plumbing within the orbital maneuvering system of the space shuttle (OMS pod). The schlieren scheme envisioned for OMS pod leak detection was that of a high contrast pattern on flexible reflecting material imaged onto a negative of the same pattern. We find that the OMS pod geometry constrains the characteristic length scale of the pattern to the order of 0.001 inch. Our experiments suggest that optical modulation transfer efficiency will be very low for such patterns, which will limit the sensitivity of the technique. Optical elements which allow a negative of the scene to be reversibly recorded using light from the scene itself were explored for their potential in adaptive single-ended schlieren systems. Elements studied include photochromic glass, bacteriorhodopsin, and a transmissive liquid crystal display. The dynamics of writing and reading patterns were studied using intensity profiles from recorded images. Schlieren detection of index gradients in air was demonstrated.
Lin, Huang-Ren; Wang, Jen-Hung; Hsieh, Jyh-Gang; Wang, Ying-Wei; Kao, Sheng-Lun
2017-01-01
A Hospice Information System (HIS) developed in eastern Taiwan in 2012 aimed to improve the quality of hospice care through an integrated system that provided telemetry-based vital sign records, online 24/7 consultations, online video interviews, and online health educations. The purpose of this study was to explore the congruence between the preferred and actual place of death (POD) among patients who received HIS services. A retrospective study was performed from January 2012 to August 2016. Data from patients enrolled in the HIS who died during this period were included. Data on basic characteristics and the actual and preferred POD were obtained from the HIS database. The primary outcome was the congruence between the preferred and actual POD. Secondary outcomes were comparisons between patients who did and did not achieve their preferred POD. Further comparisons between patients who did and did not achieve home death were also performed. In total, we enrolled 481 patients who received HIS services and died. Of them, 444 (92.3%) died at their preferred POD. Patients who preferred an inpatient hospice as their POD had higher achievement rate than those who wanted a home death. High-intensity HIS utilization was associated with a higher likelihood of home death than low-intensity HIS utilization. Patients living in areas distant from the medical center had lower achievement of home death than those living in local areas. This study suggested that patients enrolled in the HIS had high congruence between the actual and preferred POD.
Airborne UV photon-counting radiometer
NASA Astrophysics Data System (ADS)
Bauer, Marc C.; Wilcher, George; Banks, Calvin R.; Wood, Ronald L.
2000-11-01
The radiometric measurements group at the Arnold Engineering Development Center (AEDC) has developed new solar-blind radiometers for the SENSOR TALON flight test. These radiometers will be flown in an instrument pod by the 46th Test Wing at Eglin AFB. The radiometers are required to fit into a single quadrant of a 22-in.-diam sphere turret of the instrument pod. Because of minimal space requirements and photon-counting sensitivity needs, the radiometric measurements group used image intensifiers instead of the standard photomultiplier tubes (PMTs). The new design concept improved the photon-counting sensitivity, dynamic range, and uniformity of the field of view as compared to standard PMTs. A custom data acquisition system was required to miniaturize the electronics and generate a pulse code-modulated (PCM) data stream to the standard tape recording system.
2003-10-30
KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, workers discuss the next step in moving the orbital maneuvering system (OMS) pod behind them. The OMS pod will be installed on Atlantis. Two OMS pods are attached to the upper aft fuselage left and right sides. Fabricated primarily of graphite epoxy composite and aluminum, each pod is 21.8 feet long and 11.37 feet wide at its aft end and 8.41 feet wide at its forward end, with a surface area of approximately 435 square feet. Each pod houses the Reaction Control System propulsion components used for inflight maneuvering and is attached to the aft fuselage with 11 bolts.
Nico, Magalí; Mantese, Anita I.; Miralles, Daniel J.; Kantolic, Adriana G.
2016-01-01
In soybean, long days during post-flowering increase seed number. This positive photoperiodic effect on seed number has been previously associated with increments in the amount of radiation accumulated during the crop cycle because long days extend the duration of the crop cycle. However, evidence of intra-nodal processes independent of the availability of assimilates suggests that photoperiodic effects at the node level might also contribute to pod set. This work aims to identify the main mechanisms responsible for the increase in pod number per node in response to long days; including the dynamics of flowering, pod development, growth and set at the node level. Long days increased pods per node on the main stems, by increasing pods on lateral racemes (usually dominated positions) at some main stem nodes. Long days lengthened the flowering period and thereby increased the number of opened flowers on lateral racemes. The flowering period was prolonged under long days because effective seed filling was delayed on primary racemes (dominant positions). Long days also delayed the development of flowers into pods with filling seeds, delaying the initiation of pod elongation without modifying pod elongation rate. The embryo development matched the external pod length irrespective of the pod’s chronological age. These results suggest that long days during post-flowering enhance pod number per node through a relief of the competition between pods of different hierarchy within the node. The photoperiodic effect on the development of dominant pods, delaying their elongation and therefore postponing their active growth, extends flowering and allows pod set at positions that are usually dominated. PMID:26512057
Improved resistivity imaging of groundwater solute plumes using POD-based inversion
NASA Astrophysics Data System (ADS)
Oware, E. K.; Moysey, S. M.; Khan, T.
2012-12-01
We propose a new approach for enforcing physics-based regularization in electrical resistivity imaging (ERI) problems. The approach utilizes a basis-constrained inversion where an optimal set of basis vectors is extracted from training data by Proper Orthogonal Decomposition (POD). The key aspect of the approach is that Monte Carlo simulation of flow and transport is used to generate a training dataset, thereby intrinsically capturing the physics of the underlying flow and transport models in a non-parametric form. POD allows for these training data to be projected onto a subspace of the original domain, resulting in the extraction of a basis for the inversion that captures characteristics of the groundwater flow and transport system, while simultaneously allowing for dimensionality reduction of the original problem in the projected space We use two different synthetic transport scenarios in heterogeneous media to illustrate how the POD-based inversion compares with standard Tikhonov and coupled inversion. The first scenario had a single source zone leading to a unimodal solute plume (synthetic #1), whereas, the second scenario had two source zones that produced a bimodal plume (synthetic #2). For both coupled inversion and the POD approach, the conceptual flow and transport model used considered only a single source zone for both scenarios. Results were compared based on multiple metrics (concentration root-mean square error (RMSE), peak concentration, and total solute mass). In addition, results for POD inversion based on 3 different data densities (120, 300, and 560 data points) and varying number of selected basis images (100, 300, and 500) were compared. For synthetic #1, we found that all three methods provided qualitatively reasonable reproduction of the true plume. Quantitatively, the POD inversion performed best overall for each metric considered. Moreover, since synthetic #1 was consistent with the conceptual transport model, a small number of basis vectors (100) contained enough a priori information to constrain the inversion. Increasing the amount of data or number of selected basis images did not translate into significant improvement in imaging results. For synthetic #2, the RMSE and error in total mass were lowest for the POD inversion. However, the peak concentration was significantly overestimated by the POD approach. Regardless, the POD-based inversion was the only technique that could capture the bimodality of the plume in the reconstructed image, thus providing critical information that could be used to reconceptualize the transport problem. We also found that, in the case of synthetic #2, increasing the number of resistivity measurements and the number of selected basis vectors allowed for significant improvements in the reconstructed images.
Nico, Magalí; Mantese, Anita I; Miralles, Daniel J; Kantolic, Adriana G
2016-01-01
In soybean, long days during post-flowering increase seed number. This positive photoperiodic effect on seed number has been previously associated with increments in the amount of radiation accumulated during the crop cycle because long days extend the duration of the crop cycle. However, evidence of intra-nodal processes independent of the availability of assimilates suggests that photoperiodic effects at the node level might also contribute to pod set. This work aims to identify the main mechanisms responsible for the increase in pod number per node in response to long days; including the dynamics of flowering, pod development, growth and set at the node level. Long days increased pods per node on the main stems, by increasing pods on lateral racemes (usually dominated positions) at some main stem nodes. Long days lengthened the flowering period and thereby increased the number of opened flowers on lateral racemes. The flowering period was prolonged under long days because effective seed filling was delayed on primary racemes (dominant positions). Long days also delayed the development of flowers into pods with filling seeds, delaying the initiation of pod elongation without modifying pod elongation rate. The embryo development matched the external pod length irrespective of the pod's chronological age. These results suggest that long days during post-flowering enhance pod number per node through a relief of the competition between pods of different hierarchy within the node. The photoperiodic effect on the development of dominant pods, delaying their elongation and therefore postponing their active growth, extends flowering and allows pod set at positions that are usually dominated. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.
NASA Astrophysics Data System (ADS)
Ito, Kiyokazu; Matsuba, Masanori; Okamoto, Hiromi
2018-02-01
A systematic experimental study is performed to clarify the parameter dependence of the noise-induced beam instability previously demonstrated by a Princeton group [M. Chung et al., Phys. Rev. Lett. 102, 145003 (2009)]. Because of the weakness of the driving force, the instability develops very slowly, which substantially limits the application of conventional experimental and numerical techniques. In the present study, a novel tabletop apparatus called "S-POD" (Simulator of Particle Orbit Dynamics) is employed to explore the long-term collective behavior of intense hadron beams. S-POD provides a many-body Coulomb system physically equivalent to a relativistic charged-particle beam and thus enables us to conduct various beam-dynamics experiments without the use of large-scale machines. It is reconfirmed that random noise on the linear beam-focusing potential can be a source of slow beam quality degradation. Experimental observations are explained well by a simple perturbation theory that predicts the existence of a series of dangerous noise frequency bands overlooked in the previous study. Those additional instability bands newly identified with S-POD are more important practically because the driving noise frequencies can be very low. The dependence of the instability on the noise level, operating tune, and beam intensity is examined and found consistent with theoretical predictions.
MyPOD: an EMR-Based Tool that Facilitates Quality Improvement and Maintenance of Certification.
Berman, Loren; Duffy, Brian; Randall Brenn, B; Vinocur, Charles
2017-03-01
Maintenance of Certification (MOC) was designed to assess physician competencies including operative case volume and outcomes. This information, if collected consistently and systematically, can be used to facilitate quality improvement. Information automatically extracted from the electronic medical record (EMR) can be used as a prompt to compile these data. We developed an EMR-based program called MyPOD (My Personal Outcomes Data) to track surgical outcomes at our institution. We compared occurrences reported in the first 18 months to those captured in the American College of Surgeons National Surgical Quality Improvement Program-Pediatric (ACS NSQIP-P) over the same time period. During the first 18 months of using MyPOD, 691 cases were captured in both MyPOD and NSQIP-P. There were 48 cases with occurrences in NSQIP-P (6.9% occurrence rate). MyPOD captured 33% of the occurrences and 83% of the deaths reported in NSQIP-P. Use of the MyPOD program helped to identify series of complications and facilitated systematic change to improve outcomes. MyPOD provides comparative data that is essential in performance evaluation and facilitates quality improvement in surgery. This program and similar EMR-driven tools are becoming essential components of the MOC process. Our initial review has revealed opportunities for improvement in self-reporting which we can continue to measure by comparison to NSQIP-P. In addition, it has identified systems issues that have led to hospital-wide improvements.
NASA Astrophysics Data System (ADS)
Beam, Craig A.
2002-04-01
Each year, approximately 60% of all US women over the age of 40 utilize mammography. Through the matrix of an imaging technology, this Population of Patients (POP) interacts with a population of approximately 20,000 physicians who interpret mammograms in the US. This latter Population of Diagnosticians (POD) operationally serves as the interface between an image-centric healthcare technology system and patient. Methods: using data collected from a large POD and POP based study, I evaluate the distribution of several ROC curve-related parameters in the POD and explore the health policy implications of a population ROC curve for mammography. Results and Conclusions: Principal Components Analysis suggests that two Binormal parameters are sufficient to explain variation in the POD and implies that the Binormal model is foundational to Health Policy Research in Mammography. A population ROC curve based on percentiles of the POD can be used to set targets to achieve national health policy goals. Medical Image Perception science provides the framework. Alternatively, a restrictive policy can be envisioned using performance criteria based on area. However, the data suggests this sort of policy would be too costly in terms of reduced healthcare service capacity in the US in the face of burgeoning demands.
NASA Technical Reports Server (NTRS)
Kirschner, S. M.; Samii, M. V.; Broaddus, S. R.; Doll, C. E.
1988-01-01
The Preliminary Orbit Determination System (PODS) provides early orbit determination capability in the Trajectory Computation and Orbital Products System (TCOPS) for a Tracking and Data Relay Satellite System (TDRSS)-tracked spacecraft. PODS computes a set of orbit states from an a priori estimate and six tracking measurements, consisting of any combination of TDRSS range and Doppler tracking measurements. PODS uses the homotopy continuation method to solve a set of nonlinear equations, and it is particularly effective for the case when the a priori estimate is not well known. Since range and Doppler measurements produce multiple states in PODS, a screening technique selects the desired state. PODS is executed in the TCOPS environment and can directly access all operational data sets. At the completion of the preliminary orbit determination, the PODS-generated state, along with additional tracking measurements, can be directly input to the differential correction (DC) process to generate an improved state. To validate the computational and operational capabilities of PODS, tests were performed using simulated TDRSS tracking measurements for the Cosmic Background Explorer (COBE) satellite and using real TDRSS measurements for the Earth Radiation Budget Satellite (ERBS) and the Solar Mesosphere Explorer (SME) spacecraft. The effects of various measurement combinations, varying arc lengths, and levels of degradation of the a priori state vector on the PODS solutions were considered.
Krylov-Subspace Recycling via the POD-Augmented Conjugate-Gradient Method
DOE Office of Scientific and Technical Information (OSTI.GOV)
Carlberg, Kevin; Forstall, Virginia; Tuminaro, Ray
This paper presents a new Krylov-subspace-recycling method for efficiently solving sequences of linear systems of equations characterized by varying right-hand sides and symmetric-positive-definite matrices. As opposed to typical truncation strategies used in recycling such as deflation, we propose a truncation method inspired by goal-oriented proper orthogonal decomposition (POD) from model reduction. This idea is based on the observation that model reduction aims to compute a low-dimensional subspace that contains an accurate solution; as such, we expect the proposed method to generate a low-dimensional subspace that is well suited for computing solutions that can satisfy inexact tolerances. In particular, we proposemore » specific goal-oriented POD `ingredients' that align the optimality properties of POD with the objective of Krylov-subspace recycling. To compute solutions in the resulting 'augmented' POD subspace, we propose a hybrid direct/iterative three-stage method that leverages 1) the optimal ordering of POD basis vectors, and 2) well-conditioned reduced matrices. Numerical experiments performed on solid-mechanics problems highlight the benefits of the proposed method over existing approaches for Krylov-subspace recycling.« less
Krylov-Subspace Recycling via the POD-Augmented Conjugate-Gradient Method
Carlberg, Kevin; Forstall, Virginia; Tuminaro, Ray
2016-01-01
This paper presents a new Krylov-subspace-recycling method for efficiently solving sequences of linear systems of equations characterized by varying right-hand sides and symmetric-positive-definite matrices. As opposed to typical truncation strategies used in recycling such as deflation, we propose a truncation method inspired by goal-oriented proper orthogonal decomposition (POD) from model reduction. This idea is based on the observation that model reduction aims to compute a low-dimensional subspace that contains an accurate solution; as such, we expect the proposed method to generate a low-dimensional subspace that is well suited for computing solutions that can satisfy inexact tolerances. In particular, we proposemore » specific goal-oriented POD `ingredients' that align the optimality properties of POD with the objective of Krylov-subspace recycling. To compute solutions in the resulting 'augmented' POD subspace, we propose a hybrid direct/iterative three-stage method that leverages 1) the optimal ordering of POD basis vectors, and 2) well-conditioned reduced matrices. Numerical experiments performed on solid-mechanics problems highlight the benefits of the proposed method over existing approaches for Krylov-subspace recycling.« less
[The peroxidase content of human tears].
Buchberger, W; Rieger, G
1989-01-01
The peroxidase-(POD)-thiocyanate-hydrogenperoxide-system is a well-known antibacterial system, which has been demonstrated to exist, for example, in milk and saliva. Earlier investigations by van Haeringen et al. established a POD level in human tears of 10(3) units/l, yet the thiocyanate concentration was only about 0.2 mmol/l. Therefore van Haeringen et al. excluded the existence of a POD-thiocyanate-hydrogenperoxide antibacterial system in human tears because of the insufficient amount of thiocyanate in the tears examined. Instead of thiocyanate halides such as J- can also complete the POD hydrogen peroxide system as electron donors. Sufficient amounts of iodide can be expected after the application of iodine-containing eye drops or after local treatment with iodine-containing brine, as done in Bad Hall in Austria. Therefore, the above mentioned antibacterial system may be of importance if the POD-level is high enough (greater than 250 units/l). We investigated 22 tear samples from healthy persons: the POD levels were below 20 units/l in 19 cases; in 3 cases the POD concentration was found to be between 20 and 50 units/l. Therefore, in normal human tear fluid, not only the amount of thiocyanate but also the concentration of POD is too low for effective antimicrobial activity of the peroxidase-thiocyanate-hydrogenperoxide system. It is so far not known whether this system is effective under pathological conditions.
Sabatier, Rodolphe; Wiegand, Kerstin; Meyer, Katrin
2013-01-01
Ecological intensification, i.e. relying on ecological processes to replace chemical inputs, is often presented as the ideal alternative to conventional farming based on an intensive use of chemicals. It is said to both maintain high yield and provide more robustness to the agroecosystem. However few studies compared the two types of management with respect to their consequences for production and robustness toward perturbation. In this study our aim is to assess productive performance and robustness toward diverse perturbations of a Cacao agroecosystem managed with two contrasting groups of strategies: one group of strategies relying on a high level of pesticides and a second relying on low levels of pesticides. We conducted this study using a dynamical model of a Cacao agroecosystem that includes Cacao production dynamics, and dynamics of three insects: a pest (the Cacao Pod Borer, Conopomorpha cramerella) and two characteristic but unspecified beneficial insects (a pollinator of Cacao and a parasitoid of the Cacao Pod Borer). Our results showed two opposite behaviors of the Cacao agroecosystem depending on its management, i.e. an agroecosystem relying on a high input of pesticides and showing low ecosystem functioning and an agroecosystem with low inputs, relying on a high functioning of the ecosystem. From the production point of view, no type of management clearly outclassed the other and their ranking depended on the type of pesticide used. From the robustness point of view, the two types of managements performed differently when subjected to different types of perturbations. Ecologically intensive systems were more robust to pest outbreaks and perturbations related to pesticide characteristics while chemically intensive systems were more robust to Cacao production and management-related perturbation. PMID:24312469
Sabatier, Rodolphe; Wiegand, Kerstin; Meyer, Katrin
2013-01-01
Ecological intensification, i.e. relying on ecological processes to replace chemical inputs, is often presented as the ideal alternative to conventional farming based on an intensive use of chemicals. It is said to both maintain high yield and provide more robustness to the agroecosystem. However few studies compared the two types of management with respect to their consequences for production and robustness toward perturbation. In this study our aim is to assess productive performance and robustness toward diverse perturbations of a Cacao agroecosystem managed with two contrasting groups of strategies: one group of strategies relying on a high level of pesticides and a second relying on low levels of pesticides. We conducted this study using a dynamical model of a Cacao agroecosystem that includes Cacao production dynamics, and dynamics of three insects: a pest (the Cacao Pod Borer, Conopomorpha cramerella) and two characteristic but unspecified beneficial insects (a pollinator of Cacao and a parasitoid of the Cacao Pod Borer). Our results showed two opposite behaviors of the Cacao agroecosystem depending on its management, i.e. an agroecosystem relying on a high input of pesticides and showing low ecosystem functioning and an agroecosystem with low inputs, relying on a high functioning of the ecosystem. From the production point of view, no type of management clearly outclassed the other and their ranking depended on the type of pesticide used. From the robustness point of view, the two types of managements performed differently when subjected to different types of perturbations. Ecologically intensive systems were more robust to pest outbreaks and perturbations related to pesticide characteristics while chemically intensive systems were more robust to Cacao production and management-related perturbation.
Dynamic Control of Facts Devices to Enable Large Scale Penetration of Renewable Energy Resources
NASA Astrophysics Data System (ADS)
Chavan, Govind Sahadeo
This thesis focuses on some of the problems caused by large scale penetration of Renewable Energy Resources within EHV transmission networks, and investigates some approaches in resolving these problems. In chapter 4, a reduced-order model of the 500 kV WECC transmission system is developed by estimating its key parameters from phasor measurement unit (PMU) data. The model was then implemented in RTDS and was investigated for its accuracy with respect to the PMU data. Finally it was tested for observing the effects of various contingencies like transmission line loss, generation loss and large scale penetration of wind farms on EHV transmission systems. Chapter 5 introduces Static Series Synchronous Compensators (SSSC) which are seriesconnected converters that can control real power flow along a transmission line. A new application of SSSCs in mitigating Ferranti effect on unloaded transmission lines was demonstrated on PSCAD. A new control scheme for SSSCs based on the Cascaded H-bridge (CHB) converter configuration was proposed and was demonstrated using PSCAD and RTDS. A new centralized controller was developed for the distributed SSSCs based on some of the concepts used in the CHB-based SSSC. The controller's efficacy was demonstrated using RTDS. Finally chapter 6 introduces the problem of power oscillations induced by renewable sources in a transmission network. A power oscillation damping (POD) controller is designed using distributed SSSCs in NYPA's 345 kV three-bus AC system and its efficacy is demonstrated in PSCAD. A similar POD controller is then designed for the CHB-based SSSC in the IEEE 14 bus system in PSCAD. Both controllers were noted to have significantly damped power oscillations in the transmission networks.
2003-10-30
KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, an orbital maneuvering system (OMS) pod is moved into place on Atlantis. It is one of two OMS pods attached to the upper aft fuselage left and right sides. Fabricated primarily of graphite epoxy composite and aluminum, each pod is 21.8 feet long and 11.37 feet wide at its aft end and 8.41 feet wide at its forward end, with a surface area of approximately 435 square feet. Each pod houses the Reaction Control System propulsion components used for inflight maneuvering and is attached to the aft fuselage with 11 bolts.
2003-10-30
KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, an orbital maneuvering system (OMS) pod is suspended in air as it is moved toward Atlantis for installation. Two OMS pods are attached to the upper aft fuselage left and right sides. Fabricated primarily of graphite epoxy composite and aluminum, each pod is 21.8 feet long and 11.37 feet wide at its aft end and 8.41 feet wide at its forward end, with a surface area of approximately 435 square feet. Each pod houses the Reaction Control System propulsion components used for inflight maneuvering and is attached to the aft fuselage with 11 bolts.
2003-10-30
KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, an orbital maneuvering system (OMS) pod is moved closer to Atlantis for installation. Two OMS pods are attached to the upper aft fuselage left and right sides. Fabricated primarily of graphite epoxy composite and aluminum, each pod is 21.8 feet long and 11.37 feet wide at its aft end and 8.41 feet wide at its forward end, with a surface area of approximately 435 square feet. Each pod houses the Reaction Control System propulsion components used for inflight maneuvering and is attached to the aft fuselage with 11 bolts.
2003-10-30
KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, technicians make adjustments to the orbital maneuvering system (OMS) pod being installed on Atlantis. The OMS pod is one of two that are attached to the upper aft fuselage left and right sides. Fabricated primarily of graphite epoxy composite and aluminum, each pod is 21.8 feet long and 11.37 feet wide at its aft end and 8.41 feet wide at its forward end, with a surface area of approximately 435 square feet. Each pod houses the Reaction Control System propulsion components used for inflight maneuvering and is attached to the aft fuselage with 11 bolts.
2003-10-30
KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, one of two orbital maneuvering system (OMS) pods is being moved for installation on Atlantis. The OMS pods are attached to the upper aft fuselage left and right sides. Fabricated primarily of graphite epoxy composite and aluminum, each pod is 21.8 feet long and 11.37 feet wide at its aft end and 8.41 feet wide at its forward end, with a surface area of approximately 435 square feet. Each pod houses the Reaction Control System propulsion components used for inflight maneuvering and is attached to the aft fuselage with 11 bolts.
2003-10-30
KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, technicians move an orbital maneuvering system (OMS) pod into the correct position on Atlantis. The OMS pod is one of two that are attached to the upper aft fuselage left and right sides. Fabricated primarily of graphite epoxy composite and aluminum, each pod is 21.8 feet long and 11.37 feet wide at its aft end and 8.41 feet wide at its forward end, with a surface area of approximately 435 square feet. Each pod houses the Reaction Control System propulsion components used for inflight maneuvering and is attached to the aft fuselage with 11 bolts.
NASA Technical Reports Server (NTRS)
Generazio, Edward R.
2015-01-01
Directed Design of Experiments for Validating Probability of Detection Capability of NDE Systems (DOEPOD) Manual v.1.2 The capability of an inspection system is established by applications of various methodologies to determine the probability of detection (POD). One accepted metric of an adequate inspection system is that there is 95% confidence that the POD is greater than 90% (90/95 POD). Design of experiments for validating probability of detection capability of nondestructive evaluation (NDE) systems (DOEPOD) is a methodology that is implemented via software to serve as a diagnostic tool providing detailed analysis of POD test data, guidance on establishing data distribution requirements, and resolving test issues. DOEPOD demands utilization of observance of occurrences. The DOEPOD capability has been developed to provide an efficient and accurate methodology that yields observed POD and confidence bounds for both Hit-Miss or signal amplitude testing. DOEPOD does not assume prescribed POD logarithmic or similar functions with assumed adequacy over a wide range of flaw sizes and inspection system technologies, so that multi-parameter curve fitting or model optimization approaches to generate a POD curve are not required. DOEPOD applications for supporting inspector qualifications is included.
NASA Astrophysics Data System (ADS)
Du, Xiaosong; Leifsson, Leifur; Grandin, Robert; Meeker, William; Roberts, Ronald; Song, Jiming
2018-04-01
Probability of detection (POD) is widely used for measuring reliability of nondestructive testing (NDT) systems. Typically, POD is determined experimentally, while it can be enhanced by utilizing physics-based computational models in combination with model-assisted POD (MAPOD) methods. With the development of advanced physics-based methods, such as ultrasonic NDT testing, the empirical information, needed for POD methods, can be reduced. However, performing accurate numerical simulations can be prohibitively time-consuming, especially as part of stochastic analysis. In this work, stochastic surrogate models for computational physics-based measurement simulations are developed for cost savings of MAPOD methods while simultaneously ensuring sufficient accuracy. The stochastic surrogate is used to propagate the random input variables through the physics-based simulation model to obtain the joint probability distribution of the output. The POD curves are then generated based on those results. Here, the stochastic surrogates are constructed using non-intrusive polynomial chaos (NIPC) expansions. In particular, the NIPC methods used are the quadrature, ordinary least-squares (OLS), and least-angle regression sparse (LARS) techniques. The proposed approach is demonstrated on the ultrasonic testing simulation of a flat bottom hole flaw in an aluminum block. The results show that the stochastic surrogates have at least two orders of magnitude faster convergence on the statistics than direct Monte Carlo sampling (MCS). Moreover, the evaluation of the stochastic surrogate models is over three orders of magnitude faster than the underlying simulation model for this case, which is the UTSim2 model.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mishra, Srikanta; Jin, Larry; He, Jincong
2015-06-30
Reduced-order models provide a means for greatly accelerating the detailed simulations that will be required to manage CO 2 storage operations. In this work, we investigate the use of one such method, POD-TPWL, which has previously been shown to be effective in oil reservoir simulation problems. This method combines trajectory piecewise linearization (TPWL), in which the solution to a new (test) problem is represented through a linearization around the solution to a previously-simulated (training) problem, with proper orthogonal decomposition (POD), which enables solution states to be expressed in terms of a relatively small number of parameters. We describe the applicationmore » of POD-TPWL for CO 2-water systems simulated using a compositional procedure. Stanford’s Automatic Differentiation-based General Purpose Research Simulator (AD-GPRS) performs the full-order training simulations and provides the output (derivative matrices and system states) required by the POD-TPWL method. A new POD-TPWL capability introduced in this work is the use of horizontal injection wells that operate under rate (rather than bottom-hole pressure) control. Simulation results are presented for CO 2 injection into a synthetic aquifer and into a simplified model of the Mount Simon formation. Test cases involve the use of time-varying well controls that differ from those used in training runs. Results of reasonable accuracy are consistently achieved for relevant well quantities. Runtime speedups of around a factor of 370 relative to full- order AD-GPRS simulations are achieved, though the preprocessing needed for POD-TPWL model construction corresponds to the computational requirements for about 2.3 full-order simulation runs. A preliminary treatment for POD-TPWL modeling in which test cases differ from training runs in terms of geological parameters (rather than well controls) is also presented. Results in this case involve only small differences between training and test runs, though they do demonstrate that the approach is able to capture basic solution trends. The impact of some of the detailed numerical treatments within the POD-TPWL formulation is considered in an Appendix.« less
1984-02-01
of Cost Analysis Worksheets * POD Program-Economic Analysis & Methodology - Economic Evaluation Procedures for POD Investment Program - System...Approval Considerations - POD Investment Program - Potential Improvement Areas for POD - Example Cost Categories and Determinants Appendix E Long Range R&D...Funding Profiles * Investment Strategy for Integrated Circuits Diminishing Sources of Supply - Problem Scope - Approach - Alternatives - Proposed
NASA Astrophysics Data System (ADS)
Wang, H. B.; Zhao, C. Y.; Zhang, W.; Zhan, J. W.; Yu, S. X.
2015-09-01
The Earth gravitational filed model is a kind of important dynamic model in satellite orbit computation. In recent years, several space gravity missions have obtained great success, prompting a lot of gravitational filed models to be published. In this paper, 2 classical models (JGM3, EGM96) and 4 latest models, including EIGEN-CHAMP05S, GGM03S, GOCE02S, and EGM2008 are evaluated by being employed in the precision orbit determination (POD) and prediction, based on the laser range observation of four low earth orbit (LEO) satellites, including CHAMP, GFZ-1, GRACE-A, and SWARM-A. The residual error of observation in POD is adopted to describe the accuracy of six gravitational field models. We show the main results as follows: (1) for LEO POD, the accuracies of 4 latest models (EIGEN-CHAMP05S, GGM03S, GOCE02S, and EGM2008) are at the same level, and better than those of 2 classical models (JGM3, EGM96); (2) If taking JGM3 as reference, EGM96 model's accuracy is better in most situations, and the accuracies of the 4 latest models are improved by 12%-47% in POD and 63% in prediction, respectively. We also confirm that the model's accuracy in POD is enhanced with the increasing degree and order if they are smaller than 70, and when they exceed 70 the accuracy keeps stable, and is unrelated with the increasing degree, meaning that the model's degree and order truncated to 70 are sufficient to meet the requirement of LEO orbit computation with centimeter level precision.
Disaster-hardened imaging POD for PACS
NASA Astrophysics Data System (ADS)
Honeyman-Buck, Janice; Frost, Meryll
2005-04-01
After the events of 9/11, many people questioned their ability to keep critical services operational in the face of massive infrastructure failure. Hospitals increased their backup and recovery power, made plans for emergency water and food, and operated on a heightened alert awareness with more frequent disaster drills. In a film-based radiology department, if a portable X-ray unit, a CT unit, an Ultrasound unit, and an film processor could be operated on emergency power, a limited, but effective number of studies could be performed. However, in a digital department, there is a reliance on the network infrastructure to deliver images to viewing locations. The system developed for our institution uses several imaging PODS, a name we chose because it implied to us a safe, contained environment. Each POD is a stand-alone emergency powered network capable of generating images and displaying them in the POD or printing them to a DICOM printer. The technology we used to create a POD consists of a computer with dual network interface cards joining our private, local POD network, to the hospital network. In the case of an infrastructure failure, each POD can and does work independently to produce CTs, CRs, and Ultrasounds. The system has been tested during disaster drills and works correctly, producing images using equipment technologists are comfortable using with very few emergency switch-over tasks. Purpose: To provide imaging capabilities in the event of a natural or man-made disaster with infrastructure failure. Method: After the events of 9/11, many people questioned their ability to keep critical services operational in the face of massive infrastructure failure. Hospitals increased their backup and recovery power, made plans for emergency water and food, and operated on a heightened alert awareness with more frequent disaster drills. In a film-based radiology department, if a portable X-ray unit, a CT unit, an Ultrasound unit, and an film processor could be operated on emergency power, a limited, but effective number of studies could be performed. However, in a digital department, there is a reliance on the network infrastructure to deliver images to viewing locations. The system developed for our institution uses several imaging PODS, a name we chose because it implied to us a safe, contained environment. Each POD is on both the standard and the emergency power systems. All the vendor equipment that produces images is on a private, stand-alone network controlled either by a simple or a managed switch. Included in each POD is a dry-process DICOM printer that is rarely used during normal operations and a display workstation. One node on the private network is a PACS application processor (AP) with two network interface cards, one for the private network, one for the standard PACS network. During ordinary daily operations, all acquired images pass through this AP and are routed to the PACS archives, web servers, and workstations. However, if the power and network to much of the hospital were to fail, the stand-alone POD could still function. Images are routed to the AP, but cannot forward to the main network. However, they can be routed to the printer and display in the POD. They are also stored on the AP to continue normal routing when the infrastructure is restored. Results: The imaging PODS have been tested in actual disaster testing where the infrastructure was intentionally removed and worked as designed. To date, we have not had to use them in a real-life scenario and we hope we never do, but we feel we have a reasonable level of emergency imaging capability if we ever need it. Conclusions: Our testing indicates our PODS are a viable way to continue medical imaging in the face of an emergency with a major part of our network and electrical infrastructure destroyed.
Precise Orbit Determination for LEO Spacecraft Using GNSS Tracking Data from Multiple Antennas
NASA Technical Reports Server (NTRS)
Kuang, Da; Bertiger, William; Desai, Shailen; Haines, Bruce
2010-01-01
To support various applications, certain Earth-orbiting spacecrafts (e.g., SRTM, COSMIC) use multiple GNSS antennas to provide tracking data for precise orbit determination (POD). POD using GNSS tracking data from multiple antennas poses some special technical issues compared to the typical single-antenna approach. In this paper, we investigate some of these issues using both real and simulated data. Recommendations are provided for POD with multiple GNSS antennas and for antenna configuration design. The observability of satellite position with multiple antennas data is compared against single antenna case. The impact of differential clock (line biases) and line-of-sight (up, along-track, and cross-track) on kinematic and reduced-dynamic POD is evaluated. The accuracy of monitoring the stability of the spacecraft structure by simultaneously performing POD of the spacecraft and relative positioning of the multiple antennas is also investigated.
NASA Astrophysics Data System (ADS)
Han, Suyue; Chang, Gary Han; Schirmer, Clemens; Modarres-Sadeghi, Yahya
2016-11-01
We construct a reduced-order model (ROM) to study the Wall Shear Stress (WSS) distributions in image-based patient-specific aneurysms models. The magnitude of WSS has been shown to be a critical factor in growth and rupture of human aneurysms. We start the process by running a training case using Computational Fluid Dynamics (CFD) simulation with time-varying flow parameters, such that these parameters cover the range of parameters of interest. The method of snapshot Proper Orthogonal Decomposition (POD) is utilized to construct the reduced-order bases using the training CFD simulation. The resulting ROM enables us to study the flow patterns and the WSS distributions over a range of system parameters computationally very efficiently with a relatively small number of modes. This enables comprehensive analysis of the model system across a range of physiological conditions without the need to re-compute the simulation for small changes in the system parameters.
An improved algorithm for balanced POD through an analytic treatment of impulse response tails
NASA Astrophysics Data System (ADS)
Tu, Jonathan H.; Rowley, Clarence W.
2012-06-01
We present a modification of the balanced proper orthogonal decomposition (balanced POD) algorithm for systems with simple impulse response tails. In this new method, we use dynamic mode decomposition (DMD) to estimate the slowly decaying eigenvectors that dominate the long-time behavior of the direct and adjoint impulse responses. This is done using a new, low-memory variant of the DMD algorithm, appropriate for large datasets. We then formulate analytic expressions for the contribution of these eigenvectors to the controllability and observability Gramians. These contributions can be accounted for in the balanced POD algorithm by simply appending the impulse response snapshot matrices (direct and adjoint, respectively) with particular linear combinations of the slow eigenvectors. Aside from these additions to the snapshot matrices, the algorithm remains unchanged. By treating the tails analytically, we eliminate the need to run long impulse response simulations, lowering storage requirements and speeding up ensuing computations. To demonstrate its effectiveness, we apply this method to two examples: the linearized, complex Ginzburg-Landau equation, and the two-dimensional fluid flow past a cylinder. As expected, reduced-order models computed using an analytic tail match or exceed the accuracy of those computed using the standard balanced POD procedure, at a fraction of the cost.
2003-10-30
KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, technicians make final adjustments to the orbital maneuvering system (OMS) pod being installed on Atlantis. The OMS pod is one of two that are attached to the upper aft fuselage left and right sides. Fabricated primarily of graphite epoxy composite and aluminum, each pod is 21.8 feet long and 11.37 feet wide at its aft end and 8.41 feet wide at its forward end, with a surface area of approximately 435 square feet. Each pod houses the Reaction Control System propulsion components used for inflight maneuvering and is attached to the aft fuselage with 11 bolts.
2003-10-30
KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, one of two orbital maneuvering system (OMS) pods is lifted off its stand to move it toward Atlantis for installation. The OMS pods are attached to the upper aft fuselage left and right sides. Fabricated primarily of graphite epoxy composite and aluminum, each pod is 21.8 feet long and 11.37 feet wide at its aft end and 8.41 feet wide at its forward end, with a surface area of approximately 435 square feet. Each pod houses the Reaction Control System propulsion components used for inflight maneuvering and is attached to the aft fuselage with 11 bolts.
Flight test integration and evaluation of the LANTIRN system on the F-15E
NASA Astrophysics Data System (ADS)
Presuhn, Gary G.; Zeis, Joseph E.
1991-08-01
In today's high threat arena of air combat, the need to fly low, penetrate enemy defenses, strike effectively, and safely return to base is more valid than ever. The F-15E is designed to accomplish just that type of mission scenario, regardless of weather and time of day. In order to accomplish this demanding profile, any such aircraft requires terrain-following equipment and precision target designation. The LANTIRN system on the F-15E is designed to fulfill that role. This paper examines the two major aspects of the LANTIRN system found on the F-15E: the Navigation Pod and the Targeting Pod, and investigates flight test issues during F-15E integration testing. The Navigation Pod consists of two major subsystems, the Fixed Imaging Navigation Sensor (FINS) and the terrain following radar (TFR). Discussion of the FINS centers around the integration issues of the system and its utility in the night low level environment, as determined through flight test. In providing a 'window on the world,' this aspect of the LANTIRN system provides unique capabilities in navigation as well as weapons delivery. The TFR, the other major subsystem, is a continuation of the F-111 and RF-4 terrain following systems. While an effective system, integration of the TFR into the F-15E has been a challenge to the flight test community, with many lessons to be learned. The Targeting Pod is the second component of the LANTIRN system. Its purpose is to acquire and designate a target through use of its selectable dual field of view infrared sensor and laser ranger/designator. The laser also provides terminal guidance capability for precision guided weapons. Integration of the Targeting Pod into the avionics suite of the F-15E has provided classic examples of systems flight testing, evaluating both the technical and performance aspects of the pod, as well as the key human factors interface. The overall intent of this paper is to describe avionics testing, as applied to low level navigation and targeting systems, and to discuss lessons learned in that process, both of a specific and a general nature.
NASA DOE POD NDE Capabilities Data Book
NASA Technical Reports Server (NTRS)
Generazio, Edward R.
2015-01-01
This data book contains the Directed Design of Experiments for Validating Probability of Detection (POD) Capability of NDE Systems (DOEPOD) analyses of the nondestructive inspection data presented in the NTIAC, Nondestructive Evaluation (NDE) Capabilities Data Book, 3rd ed., NTIAC DB-97-02. DOEPOD is designed as a decision support system to validate inspection system, personnel, and protocol demonstrating 0.90 POD with 95% confidence at critical flaw sizes, a90/95. The test methodology used in DOEPOD is based on the field of statistical sequential analysis founded by Abraham Wald. Sequential analysis is a method of statistical inference whose characteristic feature is that the number of observations required by the procedure is not determined in advance of the experiment. The decision to terminate the experiment depends, at each stage, on the results of the observations previously made. A merit of the sequential method, as applied to testing statistical hypotheses, is that test procedures can be constructed which require, on average, a substantially smaller number of observations than equally reliable test procedures based on a predetermined number of observations.
Low-Dimensional Model of a Cylinder Wake
NASA Astrophysics Data System (ADS)
Luchtenburg, Mark; Cohen, Kelly; Siegel, Stefan; McLaughlin, Tom
2003-11-01
In a two-dimensional cylinder wake, self-excited oscillations in the form of periodic shedding of vortices are observed above a critical Reynolds number of about 47. These flow-induced non-linear oscillations lead to some undesirable effects associated with unsteady pressures such as fluid-structure interactions. An effective way of suppressing the self-excited flow oscillations is by the incorporation of closed-loop flow control. In this effort, a low dimensional, proper orthogonal decomposition (POD) model is based on data obtained from direct numerical simulations of the Navier Stokes equations for the two dimensional circular cylinder wake at a Reynolds number of 100. Three different conditions are examined, namely, the unforced wake experiencing steady-state vortex shedding, the transient behavior of the unforced wake at the startup of the simulation, and transient response to open-loop harmonic forcing by translation. We discuss POD mode selection and the number of modes that need to be included in the low-dimensional model. It is found that the transient dynamics need to be represented by a coupled system that includes an aperiodic mean-flow mode, an aperiodic shift mode and the periodic von Karman modes. Finally, a least squares mapping method is introduced to develop the non-linear state equations. The predictive capability of the state equations demonstrates the ability of the above approach to model the transient dynamics of the wake.
NASA Astrophysics Data System (ADS)
Movshovitz, N.; Asphaug, E. I.
2012-12-01
A small asteroid is likely to be the target of the next human exploration mission. Undoubtedly, a robotic mission will precede, whose main objective will be to characterize the target; this would have to include deployment of sensory instruments on the surface. The surface properties of small bodies are largely unknown, and this makes it essential to have detailed models for package deployment. We evaluate low cost, low risk, lander designs by considering 'pods' that have no moving parts, no guidance or thrust, that are designed to be thrown to the surface from the orbiting spacecraft. The design goal is to "encourage" the pods to land upright regardless of surface properties. With no need for guidance or articulation, these pods can be made and deployed to the surface at low cost and low risk. The challenge, of course, is to design the pods to land right-side-up, consistently, in a low gravity environment. In such an environment a body may experience cohesive forces comparable to its weight. These forces will effectively modify the physical parameters controlling a mechanical system, primarily the coefficients of friction and restitution. To make things worse, gravity will not always be pointing "down", as the presence of mass concentrations will tilt the gravity acceleration vector in unpredictable directions. We consider three point designs: (1) a weighted ellipsoidal shape, the bottom several times as dense as the top, analogous to the children's toy; (2) a pod with one side elastic and the other side inelastic; and (3) a combination of both weight distribution and material properties. We have used a discrete element model based on NVIDIA's PhysX library to design a simulation software suitable for modeling astrophysical rubble (Movshovitz, Asphaug and Korycansky, submitted). We then deploy different pod designs onto a numerical regolith testbed. Initial studies are very promising, although to date we have not included forces such as cohesion, and the effect of much smaller grain sizes than can be resolved in our simulations. We study the effect of bulk density, the velocity of deployment, and the effects of a tumbling or spinning deployment to the comet or asteroid surface. We are able to model the utility of internal actuators (vibrators, thumpers) that can rearrange or pods on the surface, or serve to embed them into a bed of loose soil. The size of the pods we are studying is ~30 cm average diameter. The key variables are shape, density distribution, and elastic properties, modeled by a coefficient of restitution. Our models benefit from asynchronous, parallel execution of the gravity module on a GPU, while the rigid-body dynamics module executes on a multi-threaded CPU for maximum performance.
NDE reliability and probability of detection (POD) evolution and paradigm shift
NASA Astrophysics Data System (ADS)
Singh, Surendra
2014-02-01
The subject of NDE Reliability and POD has gone through multiple phases since its humble beginning in the late 1960s. This was followed by several programs including the important one nicknamed "Have Cracks - Will Travel" or in short "Have Cracks" by Lockheed Georgia Company for US Air Force during 1974-1978. This and other studies ultimately led to a series of developments in the field of reliability and POD starting from the introduction of fracture mechanics and Damaged Tolerant Design (DTD) to statistical framework by Bernes and Hovey in 1981 for POD estimation to MIL-STD HDBK 1823 (1999) and 1823A (2009). During the last decade, various groups and researchers have further studied the reliability and POD using Model Assisted POD (MAPOD), Simulation Assisted POD (SAPOD), and applying Bayesian Statistics. All and each of these developments had one objective, i.e., improving accuracy of life prediction in components that to a large extent depends on the reliability and capability of NDE methods. Therefore, it is essential to have a reliable detection and sizing of large flaws in components. Currently, POD is used for studying reliability and capability of NDE methods, though POD data offers no absolute truth regarding NDE reliability, i.e., system capability, effects of flaw morphology, and quantifying the human factors. Furthermore, reliability and POD have been reported alike in meaning but POD is not NDE reliability. POD is a subset of the reliability that consists of six phases: 1) samples selection using DOE, 2) NDE equipment setup and calibration, 3) System Measurement Evaluation (SME) including Gage Repeatability &Reproducibility (Gage R&R) and Analysis Of Variance (ANOVA), 4) NDE system capability and electronic and physical saturation, 5) acquiring and fitting data to a model, and data analysis, and 6) POD estimation. This paper provides an overview of all major POD milestones for the last several decades and discuss rationale for using Integrated Computational Materials Engineering (ICME), MAPOD, SAPOD, and Bayesian statistics for studying controllable and non-controllable variables including human factors for estimating POD. Another objective is to list gaps between "hoped for" versus validated or fielded failed hardware.
Low-dimensional modelling of a transient cylinder wake using double proper orthogonal decomposition
NASA Astrophysics Data System (ADS)
Siegel, Stefan G.; Seidel, J.?Rgen; Fagley, Casey; Luchtenburg, D. M.; Cohen, Kelly; McLaughlin, Thomas
For the systematic development of feedback flow controllers, a numerical model that captures the dynamic behaviour of the flow field to be controlled is required. This poses a particular challenge for flow fields where the dynamic behaviour is nonlinear, and the governing equations cannot easily be solved in closed form. This has led to many versions of low-dimensional modelling techniques, which we extend in this work to represent better the impact of actuation on the flow. For the benchmark problem of a circular cylinder wake in the laminar regime, we introduce a novel extension to the proper orthogonal decomposition (POD) procedure that facilitates mode construction from transient data sets. We demonstrate the performance of this new decomposition by applying it to a data set from the development of the limit cycle oscillation of a circular cylinder wake simulation as well as an ensemble of transient forced simulation results. The modes obtained from this decomposition, which we refer to as the double POD (DPOD) method, correctly track the changes of the spatial modes both during the evolution of the limit cycle and when forcing is applied by transverse translation of the cylinder. The mode amplitudes, which are obtained by projecting the original data sets onto the truncated DPOD modes, can be used to construct a dynamic mathematical model of the wake that accurately predicts the wake flow dynamics within the lock-in region at low forcing amplitudes. This low-dimensional model, derived using nonlinear artificial neural network based system identification methods, is robust and accurate and can be used to simulate the dynamic behaviour of the wake flow. We demonstrate this ability not just for unforced and open-loop forced data, but also for a feedback-controlled simulation that leads to a 90% reduction in lift fluctuations. This indicates the possibility of constructing accurate dynamic low-dimensional models for feedback control by using unforced and transient forced data only.
NASA Astrophysics Data System (ADS)
Kikuchi, Ryota; Misaka, Takashi; Obayashi, Shigeru
2016-04-01
An integrated method consisting of a proper orthogonal decomposition (POD)-based reduced-order model (ROM) and a particle filter (PF) is proposed for real-time prediction of an unsteady flow field. The proposed method is validated using identical twin experiments of an unsteady flow field around a circular cylinder for Reynolds numbers of 100 and 1000. In this study, a PF is employed (ROM-PF) to modify the temporal coefficient of the ROM based on observation data because the prediction capability of the ROM alone is limited due to the stability issue. The proposed method reproduces the unsteady flow field several orders faster than a reference numerical simulation based on Navier-Stokes equations. Furthermore, the effects of parameters, related to observation and simulation, on the prediction accuracy are studied. Most of the energy modes of the unsteady flow field are captured, and it is possible to stably predict the long-term evolution with ROM-PF.
Vortex-based spatiotemporal characterization of nonlinear flows
NASA Astrophysics Data System (ADS)
Byrne, Gregory A.
Although the ubiquity of vortices in nature has been recognized by artists for over seven centuries, it was the work of artist and scientist Leonardo da Vinci that provided the monumental transition from an aesthetic form to a scientific tool. DaVinci used vortices to describe the motions he observed in air currents, flowing water and blood flow in the human heart. Five centuries later, the Navier-Stokes equations allow us to recreate the swirling motions of fluid observed in nature. Computational fluid dynamic (CFD) simulations have provided a lens through which to study the role of vortices in a wide variety of modern day applications. The research summarized below represents an effort to look through this lens and bring into focus the practical use of vortices in describing nonlinear flows. Vortex-based spatiotemporal characterizations are obtained using two specific mathematical tools: vortex core lines (VCL) and proper orthogonal decomposition (POD). By applying these tools, we find that vortices continue to provide new insights in the realm of biofluids, urban flows and the phase space of dynamical systems. The insights we have gained are described in this thesis. Our primary focus is on biofluids. Specifically, we seek to gain new insights into the connection between vortices and vascular diseases in order to provide more effective methods for clinical diagnosis and treatment. We highlight several applications in which VCL and POD are used to characterize the flow conditions in a heart pump, identify stenosis in carotid arteries and validate numerical models against PIV-based experimental data. Next, we quantify the spatial complexity and temporal stability of hemodynamics generated by a database of 210 patient-specific aneurysm geometries. Visual classifications of the hemodynamics are compared to the automated, quantitative classifications. The quantities characterizing the hemodynamics are then compared to clinical data to determine conditions that are most conducive to rupture. Flows that form multiple vortices and undergo large-scale structural changes over the cardiac cycle are found to pose the most significant risk to patients. Concepts from dynamical systems are then applied to explain the formation of large-scale vortical flow structures in cerebral aneurysms. This is done by investigating the role of critical points along vortex core lines. We provide evidence that critical points are created and destroyed in saddle-node bifurcations during the cardiac cycle and that these bifurcations are responsible for changing the large-scale flow structure inside the aneurysm. Uncovering and understanding these mechanisms is the first step towards individualized treatments designed to suppress the creation of specific blood flow patterns that are known to present a risk of rupture. A simple differential dynamical system is used to illustrate the dynamical systems related concepts. Two examples illustrating the use of vortex-based methods in other domains are highlighted at the end of this work. The first example uses realistic CFD modeling of air flow through subway tunnels and stations to study the spread of accidental or planned release of airborne chemical or biological contaminants. Quantities from the vortex-based characterizations are shown to provide clear signatures that correlate to the dispersion and transport of pollutants though the stations. The second example examines swirling flow structures in the phase space of dynamical systems. Descriptions of vortices and their properties are extended to higher dimensions within the special class of differential dynamical systems.
NASA Technical Reports Server (NTRS)
Piascik, Robert S.; Prosser, William H.
2011-01-01
The Director of the NASA Engineering and Safety Center (NESC), requested an independent assessment of the anomalous gaseous hydrogen (GH2) flow incident on the Space Shuttle Program (SSP) Orbiter Vehicle (OV)-105 during the Space Transportation System (STS)-126 mission. The main propulsion system (MPS) engine #2 GH2 flow control valve (FCV) LV-57 transition from low towards high flow position without being commanded. Post-flight examination revealed that the FCV LV-57 poppet had experienced a fatigue failure that liberated a section of the poppet flange. The NESC assessment provided a peer review of the computational fluid dynamics (CFD), stress analysis, and impact testing. A probability of detection (POD) study was requested by the SSP Orbiter Project for the eddy current (EC) nondestructive evaluation (NDE) techniques that were developed to inspect the flight FCV poppets. This report contains the findings and recommendations from the NESC assessment.
NASA Technical Reports Server (NTRS)
Piascik, Robert S.; Prosser, William H.
2011-01-01
The Director of the NASA Engineering and Safety Center (NESC), requested an independent assessment of the anomalous gaseous hydrogen (GH2) flow incident on the Space Shuttle Program (SSP) Orbiter Vehicle (OV)-105 during the Space Transportation System (STS)-126 mission. The main propulsion system (MPS) engine #2 GH2 flow control valve (FCV) LV-57 transition from low towards high flow position without being commanded. Post-flight examination revealed that the FCV LV-57 poppet had experienced a fatigue failure that liberated a section of the poppet flange. The NESC assessment provided a peer review of the computational fluid dynamics (CFD), stress analysis, and impact testing. A probability of detection (POD) study was requested by the SSP Orbiter Project for the eddy current (EC) nondestructive evaluation (NDE) techniques that were developed to inspect the flight FCV poppets. This report contains the Appendices to the main report.
Wang, Hao; Zhu, Dexiang; Liang, Li; Ye, Lechi; Lin, Qi; Zhong, Yunshi; Wei, Ye; Ren, Li; Xu, Jianmin; Qin, Xinyu
2015-11-01
Enhanced recovery after surgery (ERAS) integrates evidence-based interventions to reduce surgical stress and accelerate rehabilitation. Our study was to compare the short-term quality of life (QOL) in patients undergoing open colonic surgery using ERAS program or conventional management. A prospective study of 57 patients using ERAS program and 60 patients using conventional management was conducted. The clinical characteristics of all patients were recorded. QOL was evaluated longitudinally using the questionnaires (EORTC QLQ-C30 and QLQ-CR29) pre- and postoperatively. Generalized estimating equation was used to do the analysis in order to determine the effective impact of correlative factors on the postoperative QOL, including age, sex, BMI, ASA grade, tumor location, tumor size, pTNM stage, recovery program and length of time after surgery. The morbidity in ERAS and control group was 17.5 versus 26.7 % (p = 0.235). The patients in ERAS group had much faster rehabilitation and less hospital stay. In the primary statistical analysis, the scores of global QOL (on POD3, POD6, POD10, POD14, POD21), physical functioning (on POD3, POD6, POD10, POD14, POD21), role functioning (on POD6, POD10, POD14, POD21), emotional functioning (on POD3, POD6, POD10, POD14, POD21), cognitive functioning (on POD3, POD6) and social functioning (on POD3, POD6, POD10, POD14, POD21, POD28) were higher in ERAS group than in control group, which suggested that the patients in ERAS group had a better life status. However, the scores of pain (on POD10, POD14, POD21), appetite loss (on POD3, POD6), constipation (on POD3, POD6, POD10), diarrhea (on POD3, POD10), financial difficulties (on POD10, POD14, POD21), perspective of future health (on POD6, POD10, POD14), gastrointestinal tract problems (on POD3, POD6, POD10) and defecation problems (on POD6, POD10, POD14) were lower in ERAS group than in control group, which revealed that the patients in ERAS group suffered less symptoms. In the further generalized estimating equation analysis, the result showed that recovery program and length of time after surgery had independently positive impact on the patient's postoperative QOL. Short-term QOL in patients undergoing colonic cancer using ERAS program was better than that using conventional management.
Validity and reliability of the BOD POD® S/T tracking system.
Tseh, W; Caputo, J L; Keefer, D J
2010-10-01
BOD POD(®) self-testing (S/T) body composition tracking system is a practical assessment tool designed for use in the health and fitness industries. Relative to its parent counterpart, the BOD POD(®) S/T has received little research attention. The primary purpose was to determine the validity of the BOD POD(®) S/T against hydrostatic weighing and 7-site skinfolds. Secondary aim was to determine the within-day and between-day reliability of the BOD POD(®) S/T. After a period of equipment and testing accommodation, volunteer's (N=50) body composition (%BF) via 7-site skinfolds, BOD POD(®) S/T, and hydrostatic weighing were obtained on the second and third visits. BOD POD(®) S/T significantly overestimated %BF when compared to hydrostatic weighing and 7-site skinfolds. There was no statistical difference between 7-site skinfolds and hydrostatic weighing values. BOD POD(®) S/T reliability within-day and between-days were high. While the BOD POD(®) S/T body composition tracking system is deemed reliable both within-day and between-days, it did significantly overestimate %BF in comparison to hydrostatic weighing and skinfolds. Future research should be aimed at deriving a correction factor for this body composition assessment tool. © Georg Thieme Verlag KG Stuttgart · New York.
NDE reliability and probability of detection (POD) evolution and paradigm shift
DOE Office of Scientific and Technical Information (OSTI.GOV)
Singh, Surendra
2014-02-18
The subject of NDE Reliability and POD has gone through multiple phases since its humble beginning in the late 1960s. This was followed by several programs including the important one nicknamed “Have Cracks – Will Travel” or in short “Have Cracks” by Lockheed Georgia Company for US Air Force during 1974–1978. This and other studies ultimately led to a series of developments in the field of reliability and POD starting from the introduction of fracture mechanics and Damaged Tolerant Design (DTD) to statistical framework by Bernes and Hovey in 1981 for POD estimation to MIL-STD HDBK 1823 (1999) and 1823Amore » (2009). During the last decade, various groups and researchers have further studied the reliability and POD using Model Assisted POD (MAPOD), Simulation Assisted POD (SAPOD), and applying Bayesian Statistics. All and each of these developments had one objective, i.e., improving accuracy of life prediction in components that to a large extent depends on the reliability and capability of NDE methods. Therefore, it is essential to have a reliable detection and sizing of large flaws in components. Currently, POD is used for studying reliability and capability of NDE methods, though POD data offers no absolute truth regarding NDE reliability, i.e., system capability, effects of flaw morphology, and quantifying the human factors. Furthermore, reliability and POD have been reported alike in meaning but POD is not NDE reliability. POD is a subset of the reliability that consists of six phases: 1) samples selection using DOE, 2) NDE equipment setup and calibration, 3) System Measurement Evaluation (SME) including Gage Repeatability and Reproducibility (Gage R and R) and Analysis Of Variance (ANOVA), 4) NDE system capability and electronic and physical saturation, 5) acquiring and fitting data to a model, and data analysis, and 6) POD estimation. This paper provides an overview of all major POD milestones for the last several decades and discuss rationale for using Integrated Computational Materials Engineering (ICME), MAPOD, SAPOD, and Bayesian statistics for studying controllable and non-controllable variables including human factors for estimating POD. Another objective is to list gaps between “hoped for” versus validated or fielded failed hardware.« less
Probability of detection of defects in coatings with electronic shearography
NASA Technical Reports Server (NTRS)
Russell, S. S.; Lansing, M. D.; Horton, C. M.; Gnacek, W. J.
1995-01-01
The goal of this research was to utilize statistical methods to evaluate the probability of detection (POD) of defects in coatings using electronic shearography. The coating system utilized in the POD studies was to be the paint system currently utilized on the external casings of the NASA space transportation system reusable solid rocket motor boosters. The population of samples was to be large enough to determine the minimum defect size for 90-percent POD of 95-percent confidence POD on these coatings. Also, the best methods to excite coatings on aerospace components to induce deformations for measurement by electronic shearography were to be determined.
El-Gabalawy, Renée; Patel, Ronak; Kilborn, Kayla; Blaney, Caitlin; Hoban, Christopher; Ryner, Lawrence; Funk, Duane; Legaspi, Regina; Fisher, Joseph A; Duffin, James; Mikulis, David J; Mutch, W Alan C
2017-01-01
Introduction: Risk assessment for post-operative delirium (POD) is poorly developed. Improved metrics could greatly facilitate peri-operative care as costs associated with POD are staggering. In this preliminary study, we develop a novel stress-diathesis model based on comprehensive pre-operative psychiatric and neuropsychological testing, a blood oxygenation level-dependent (BOLD) magnetic resonance imaging (MRI) carbon dioxide (CO 2 ) stress test, and high fidelity measures of intra-operative parameters that may interact facilitating POD. Methods: The study was approved by the ethics board at the University of Manitoba and registered at clinicaltrials.gov as NCT02126215. Twelve patients were studied. Pre-operative psychiatric symptom measures and neuropsychological testing preceded MRI featuring a BOLD MRI CO 2 stress test whereby BOLD scans were conducted while exposing participants to a rigorously controlled CO 2 stimulus. During surgery the patient had hemodynamics and end-tidal gases downloaded at 0.5 hz. Post-operatively, the presence of POD and POD severity was comprehensively assessed using the Confusion Assessment Measure -Severity (CAM-S) scoring instrument on days 0 (surgery) through post-operative day 5, and patients were followed up at least 1 month post-operatively. Results: Six of 12 patients had no evidence of POD (non-POD). Three patients had POD and 3 had clinically significant confusional states (referred as subthreshold POD; ST-POD) (score ≥ 5/19 on the CAM-S). Average severity for delirium was 1.3 in the non-POD group, 3.2 in ST-POD, and 6.1 in POD (F-statistic = 15.4, p < 0.001). Depressive symptoms, and cognitive measures of semantic fluency and executive functioning/processing speed were significantly associated with POD. Second level analysis revealed an increased inverse BOLD responsiveness to CO 2 pre-operatively in ST-POD and marked increase in the POD groups when compared to the non-POD group. An association was also noted for the patient population to manifest leucoaraiosis as assessed with advanced neuroimaging techniques. Results provide preliminary support for the interacting of diatheses (vulnerabilities) and intra-operative stressors on the POD phenotype. Conclusions: The stress-diathesis model has the potential to aid in risk assessment for POD. Based on these initial findings, we make some recommendations for intra-operative management for patients at risk of POD.
El-Gabalawy, Renée; Patel, Ronak; Kilborn, Kayla; Blaney, Caitlin; Hoban, Christopher; Ryner, Lawrence; Funk, Duane; Legaspi, Regina; Fisher, Joseph A.; Duffin, James; Mikulis, David J.; Mutch, W. Alan C.
2017-01-01
Introduction: Risk assessment for post-operative delirium (POD) is poorly developed. Improved metrics could greatly facilitate peri-operative care as costs associated with POD are staggering. In this preliminary study, we develop a novel stress-diathesis model based on comprehensive pre-operative psychiatric and neuropsychological testing, a blood oxygenation level-dependent (BOLD) magnetic resonance imaging (MRI) carbon dioxide (CO2) stress test, and high fidelity measures of intra-operative parameters that may interact facilitating POD. Methods: The study was approved by the ethics board at the University of Manitoba and registered at clinicaltrials.gov as NCT02126215. Twelve patients were studied. Pre-operative psychiatric symptom measures and neuropsychological testing preceded MRI featuring a BOLD MRI CO2 stress test whereby BOLD scans were conducted while exposing participants to a rigorously controlled CO2 stimulus. During surgery the patient had hemodynamics and end-tidal gases downloaded at 0.5 hz. Post-operatively, the presence of POD and POD severity was comprehensively assessed using the Confusion Assessment Measure –Severity (CAM-S) scoring instrument on days 0 (surgery) through post-operative day 5, and patients were followed up at least 1 month post-operatively. Results: Six of 12 patients had no evidence of POD (non-POD). Three patients had POD and 3 had clinically significant confusional states (referred as subthreshold POD; ST-POD) (score ≥ 5/19 on the CAM-S). Average severity for delirium was 1.3 in the non-POD group, 3.2 in ST-POD, and 6.1 in POD (F-statistic = 15.4, p < 0.001). Depressive symptoms, and cognitive measures of semantic fluency and executive functioning/processing speed were significantly associated with POD. Second level analysis revealed an increased inverse BOLD responsiveness to CO2 pre-operatively in ST-POD and marked increase in the POD groups when compared to the non-POD group. An association was also noted for the patient population to manifest leucoaraiosis as assessed with advanced neuroimaging techniques. Results provide preliminary support for the interacting of diatheses (vulnerabilities) and intra-operative stressors on the POD phenotype. Conclusions: The stress-diathesis model has the potential to aid in risk assessment for POD. Based on these initial findings, we make some recommendations for intra-operative management for patients at risk of POD. PMID:28868035
Characterization of renin-angiotensin system enzyme activities in cultured mouse podocytes.
Velez, Juan Carlos Q; Bland, Alison M; Arthur, John M; Raymond, John R; Janech, Michael G
2007-07-01
Intraglomerular ANG II has been linked to glomerular injury. However, little is known about the contribution of podocytes (POD) to intraglomerular ANG II homeostasis. The aim of the present study was to examine the processing of angiotensin substrates by cultured POD. Our approach was to use matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry for peptide determination from conditioned cell media and customized AQUA peptides for quantification. Immortalized mouse POD were incubated with 1-2 microM ANG I, ANG II, or the renin substrate ANG-(1-14) for different time intervals and coincubated in parallel with various inhibitors. Human mesangial cells (MES) were used as controls. POD incubated with 1 microM ANG I primarily formed ANG-(1-9) and ANG-(1-7). In contrast, MES incubated with ANG I primarily generated ANG II. In POD, ANG-(1-7) was the predominant product, and its formation was inhibited by a neprilysin inhibitor. Modest angiotensin-converting enzyme (ACE) activity was also detected in POD, although only after cells were incubated with 2 microM ANG I. In addition, we observed that POD degraded ANG II into ANG III and ANG-(1-7). An aminopeptidase A inhibitor inhibited ANG III formation, and an ACE2 inhibitor led to ANG II accumulation. Furthermore, we found that POD converted ANG-(1-14) to ANG I and ANG-(1-7). This conversion was inhibited by a renin inhibitor. These findings demonstrate that POD express a functional intrinsic renin-angiotensin system characterized by neprilysin, aminopeptidase A, ACE2, and renin activities, which predominantly lead to ANG-(1-7) and ANG-(1-9) formation, as well as ANG II degradation. These findings may reflect a specific role of POD in maintenance of intraglomerular renin-angiotensin system balance.
Transport coefficient computation based on input/output reduced order models
NASA Astrophysics Data System (ADS)
Hurst, Joshua L.
The guiding purpose of this thesis is to address the optimal material design problem when the material description is a molecular dynamics model. The end goal is to obtain a simplified and fast model that captures the property of interest such that it can be used in controller design and optimization. The approach is to examine model reduction analysis and methods to capture a specific property of interest, in this case viscosity, or more generally complex modulus or complex viscosity. This property and other transport coefficients are defined by a input/output relationship and this motivates model reduction techniques that are tailored to preserve input/output behavior. In particular Singular Value Decomposition (SVD) based methods are investigated. First simulation methods are identified that are amenable to systems theory analysis. For viscosity, these models are of the Gosling and Lees-Edwards type. They are high order nonlinear Ordinary Differential Equations (ODEs) that employ Periodic Boundary Conditions. Properties can be calculated from the state trajectories of these ODEs. In this research local linear approximations are rigorously derived and special attention is given to potentials that are evaluated with Periodic Boundary Conditions (PBC). For the Gosling description LTI models are developed from state trajectories but are found to have limited success in capturing the system property, even though it is shown that full order LTI models can be well approximated by reduced order LTI models. For the Lees-Edwards SLLOD type model nonlinear ODEs will be approximated by a Linear Time Varying (LTV) model about some nominal trajectory and both balanced truncation and Proper Orthogonal Decomposition (POD) will be used to assess the plausibility of reduced order models to this system description. An immediate application of the derived LTV models is Quasilinearization or Waveform Relaxation. Quasilinearization is a Newton's method applied to the ODE operator equation. Its a recursive method that solves nonlinear ODE's by solving a LTV systems at each iteration to obtain a new closer solution. LTV models are derived for both Gosling and Lees-Edwards type models. Particular attention is given to SLLOD Lees-Edwards models because they are in a form most amenable to performing Taylor series expansion, and the most commonly used model to examine viscosity. With linear models developed a method is presented to calculate viscosity based on LTI Gosling models but is shown to have some limitations. To address these issues LTV SLLOD models are analyzed with both Balanced Truncation and POD and both show that significant order reduction is possible. By examining the singular values of both techniques it is shown that Balanced Truncation has a potential to offer greater reduction, which should be expected as it is based on the input/output mapping instead of just the state information as in POD. Obtaining reduced order systems that capture the property of interest is challenging. For Balanced Truncation reduced order models for 1-D LJ and FENE systems are obtained and are shown to capture the output of interest fairly well. However numerical challenges currently limit this analysis to small order systems. Suggestions are presented to extend this method to larger systems. In addition reduced 2nd order systems are obtained from POD. Here the challenge is extending the solution beyond the original period used for the projection, in particular identifying the manifold the solution travels along. The remaining challenges are presented and discussed.
Personnel occupied woven envelope robot
NASA Technical Reports Server (NTRS)
Wessling, Francis; Teoh, William; Ziemke, M. Carl
1988-01-01
The Personnel Occupied Woven Envelope Robot (POWER) provides an alternative to extravehicular activity (EVA) of space suited astronauts and/or use of long slender manipulator arms such as are used in the Shuttle Remote Manipulator System. POWER provides the capability for a shirt sleeved astronaut to perform such work by entering a control pod through air locks at both ends of an inflated flexible bellows (access tunnel). The exoskeleton of the tunnel is a series of six degrees of freedom (Six-DOF) articulated links compressible to 1/6 of their fully extended length. The operator can maneuver the control pod to almost any location within about 50 m of the base attachment to the space station. POWER can be envisioned as a series of hollow Six-DOF manipulator segments or arms wherein each arm grasps the shoulder of the next arm. Inside the hollow arms ia a bellow-type access tunnel. The control pod is the fist of the series of linked hollow arms. The fingers of the fist are conventional manipulator arms under direct visual control of the nearby operator in the pod. The applications and progress to date of the POWER system is given.
NASA Astrophysics Data System (ADS)
Margheri, Luca; Sagaut, Pierre
2016-11-01
To significantly increase the contribution of numerical computational fluid dynamics (CFD) simulation for risk assessment and decision making, it is important to quantitatively measure the impact of uncertainties to assess the reliability and robustness of the results. As unsteady high-fidelity CFD simulations are becoming the standard for industrial applications, reducing the number of required samples to perform sensitivity (SA) and uncertainty quantification (UQ) analysis is an actual engineering challenge. The novel approach presented in this paper is based on an efficient hybridization between the anchored-ANOVA and the POD/Kriging methods, which have already been used in CFD-UQ realistic applications, and the definition of best practices to achieve global accuracy. The anchored-ANOVA method is used to efficiently reduce the UQ dimension space, while the POD/Kriging is used to smooth and interpolate each anchored-ANOVA term. The main advantages of the proposed method are illustrated through four applications with increasing complexity, most of them based on Large-Eddy Simulation as a high-fidelity CFD tool: the turbulent channel flow, the flow around an isolated bluff-body, a pedestrian wind comfort study in a full scale urban area and an application to toxic gas dispersion in a full scale city area. The proposed c-APK method (anchored-ANOVA-POD/Kriging) inherits the advantages of each key element: interpolation through POD/Kriging precludes the use of quadrature schemes therefore allowing for a more flexible sampling strategy while the ANOVA decomposition allows for a better domain exploration. A comparison of the three methods is given for each application. In addition, the importance of adding flexibility to the control parameters and the choice of the quantity of interest (QoI) are discussed. As a result, global accuracy can be achieved with a reasonable number of samples allowing computationally expensive CFD-UQ analysis.
Advanced Airborne Defensive Laser for Incorporation on Strike Fighter Aircraft
2017-09-01
Systems within the Pod The Cyclops pod contains several systems working together to perform the high - level functions. The status of these systems must be...by the aircraft is limited, and Cyclops power requirements are high . commercial off-the-shelf (COTS) Ram Air Turbines are available and are...Supply Subsystem The Cyclops pod must generate its own power due to lack of available power from the aircraft; therefore, the Power supply has high
NASA DOEPOD NDE Capabilities Data Book
NASA Technical Reports Server (NTRS)
Generazio, Edward R.
2015-01-01
This data book contains the Directed Design of Experiments for Validating Probability of Detection (POD) Capability of NDE Systems (DOEPOD) analyses of the nondestructive inspection data presented in the NTIAC, Nondestructive Evaluation (NDE) Capabilities Data Book. DOEPOD is designed as a decision support system to validate inspection system, personnel, and protocol demonstrating 0.90 POD with 95% confidence at critical flaw sizes, a90/95. Although 0.90 POD with 95% confidence at critical flaw sizes is often stated as an inspection requirement in inspection documents, including NASA Standards, NASA critical aerospace applications have historically only accepted 0.978 POD or better with a 95% one-sided lower confidence bound exceeding 0.90 at critical flaw sizes, a90/95.
Lu, Jia; Zheng, Lei; Li, Runtian; Hao, Chunmin; Gao, Wenbin; Feng, Ziwei; Yin, Guangya; Wang, Yue
2017-09-25
To evaluate the diagnostic value of dynamic monitoring of C-reactive protein (CRP) in drainage fluid in predicting early anastomotic leakage after colorectal surgery. This study enrolled 172 patients, who were diagnosed as colorectal cancer before operation and underwent radical surgery, without residual tumor tissues by postoperative pathology and perioperative infection, at the Tianjin Medical University Cancer Hospital between July 2015 and January 2016. The C-reactive(CRP) protein level in drainage fluid was continuously monitored from postoperative days (POD) 1 to 5. CRP level was compared between anastomotic leakage (AL) group and non-anastomotic leakage (NAL) group. Receiver operating characteristics (ROC) curve was used to estimate the value of monitoring CRP in drainage fluid to predict anastomotic leakage after colorectal surgery. Among 172 patients, 101 cases were male and 71 cases were female, with age of (59.9±10.3) years. Anastomotic leakage occurred after colorectal surgery in 24 cases(14.0%, AL group ) and other 148 cases were defined as NAL group. Other than body mass index (BMI), differences in baseline data were not statistically significant between two groups. The CRP lever in AL group and NAL group showed rising trend from POD1 to POD4 [Day 1: (6.7±8.4) g/L vs. (8.0±10.6) g/L; Day 2: (24.8±14.6) g/L vs. (28.3±21.1) g/L, Day 3: (54.8±26.5) g/L vs. (53.8±27.6)g/L, Day 4: (62.0±32.2) g/L vs. (58.4±30.7) g/L], while the differences were not significant (all P>0.05). At POD 5, the CRP lever of AL group increased continuously, while that of NAL group decreased with significant difference [(65.3±38.9) g/L vs. (44.7±39.5) g/L, t=-2.85, P=0.005]. Further stratification analysis on AL group revealed CRP level in early AL (AL occurrence
Improving BeiDou precise orbit determination using observations of onboard MEO satellite receivers
NASA Astrophysics Data System (ADS)
Ge, Haibo; Li, Bofeng; Ge, Maorong; Shen, Yunzhong; Schuh, Harald
2017-12-01
In recent years, the precise orbit determination (POD) of the regional Chinese BeiDou Navigation Satellite System (BDS) has been a hot spot because of its special constellation consisting of five geostationary earth orbit (GEO) satellites and five inclined geosynchronous satellite orbit (IGSO) satellites besides four medium earth orbit (MEO) satellites since the end of 2012. GEO and IGSO satellites play an important role in regional BDS applications. However, this brings a great challenge to the POD, especially for the GEO satellites due to their geostationary orbiting. Though a number of studies have been carried out to improve the POD performance of GEO satellites, the result is still much worse than that of IGSO and MEO, particularly in the along-track direction. The major reason is that the geostationary characteristic of a GEO satellite results in a bad geometry with respect to the ground tracking network. In order to improve the tracking geometry of the GEO satellites, a possible strategy is to mount global navigation satellite system (GNSS) receivers on MEO satellites to collect the signals from GEO/IGSO GNSS satellites so as that these observations can be used to improve GEO/IGSO POD. We extended our POD software package to simulate all the related observations and to assimilate the MEO-onboard GNSS observations in orbit determination. Based on GPS and BDS constellations, simulated studies are undertaken for various tracking scenarios. The impact of the onboard GNSS observations is investigated carefully and presented in detail. The results show that MEO-onboard observations can significantly improve the orbit precision of GEO satellites from metres to decimetres, especially in the along-track direction. The POD results of IGSO satellites also benefit from the MEO-onboard data and the precision can be improved by more than 50% in 3D direction.
NASA Astrophysics Data System (ADS)
Lee, Kyunghoon
To evaluate the maximum likelihood estimates (MLEs) of probabilistic principal component analysis (PPCA) parameters such as a factor-loading, PPCA can invoke an expectation-maximization (EM) algorithm, yielding an EM algorithm for PPCA (EM-PCA). In order to examine the benefits of the EM-PCA for aerospace engineering applications, this thesis attempts to qualitatively and quantitatively scrutinize the EM-PCA alongside both POD and gappy POD using high-dimensional simulation data. In pursuing qualitative investigations, the theoretical relationship between POD and PPCA is transparent such that the factor-loading MLE of PPCA, evaluated by the EM-PCA, pertains to an orthogonal basis obtained by POD. By contrast, the analytical connection between gappy POD and the EM-PCA is nebulous because they distinctively approximate missing data due to their antithetical formulation perspectives: gappy POD solves a least-squares problem whereas the EM-PCA relies on the expectation of the observation probability model. To juxtapose both gappy POD and the EM-PCA, this research proposes a unifying least-squares perspective that embraces the two disparate algorithms within a generalized least-squares framework. As a result, the unifying perspective reveals that both methods address similar least-squares problems; however, their formulations contain dissimilar bases and norms. Furthermore, this research delves into the ramifications of the different bases and norms that will eventually characterize the traits of both methods. To this end, two hybrid algorithms of gappy POD and the EM-PCA are devised and compared to the original algorithms for a qualitative illustration of the different basis and norm effects. After all, a norm reflecting a curve-fitting method is found to more significantly affect estimation error reduction than a basis for two example test data sets: one is absent of data only at a single snapshot and the other misses data across all the snapshots. From a numerical performance aspect, the EM-PCA is computationally less efficient than POD for intact data since it suffers from slow convergence inherited from the EM algorithm. For incomplete data, this thesis quantitatively found that the number of data missing snapshots predetermines whether the EM-PCA or gappy POD outperforms the other because of the computational cost of a coefficient evaluation, resulting from a norm selection. For instance, gappy POD demands laborious computational effort in proportion to the number of data-missing snapshots as a consequence of the gappy norm. In contrast, the computational cost of the EM-PCA is invariant to the number of data-missing snapshots thanks to the L2 norm. In general, the higher the number of data-missing snapshots, the wider the gap between the computational cost of gappy POD and the EM-PCA. Based on the numerical experiments reported in this thesis, the following criterion is recommended regarding the selection between gappy POD and the EM-PCA for computational efficiency: gappy POD for an incomplete data set containing a few data-missing snapshots and the EM-PCA for an incomplete data set involving multiple data-missing snapshots. Last, the EM-PCA is applied to two aerospace applications in comparison to gappy POD as a proof of concept: one with an emphasis on basis extraction and the other with a focus on missing data reconstruction for a given incomplete data set with scattered missing data. The first application exploits the EM-PCA to efficiently construct reduced-order models of engine deck responses obtained by the numerical propulsion system simulation (NPSS), some of whose results are absent due to failed analyses caused by numerical instability. Model-prediction tests validate that engine performance metrics estimated by the reduced-order NPSS model exhibit considerably good agreement with those directly obtained by NPSS. Similarly, the second application illustrates that the EM-PCA is significantly more cost effective than gappy POD at repairing spurious PIV measurements obtained from acoustically-excited, bluff-body jet flow experiments. The EM-PCA reduces computational cost on factors 8 ˜ 19 compared to gappy POD while generating the same restoration results as those evaluated by gappy POD. All in all, through comprehensive theoretical and numerical investigation, this research establishes that the EM-PCA is an efficient alternative to gappy POD for an incomplete data set containing missing data over an entire data set. (Abstract shortened by UMI.)
Cooperative Autonomous Observation of Volcanic Environments with sUAS
NASA Astrophysics Data System (ADS)
Ravela, S.
2015-12-01
The Cooperative Autonomous Observing System Project (CAOS) at the MIT Earth Signals and Systems Group has developed methodology and systems for dynamically mapping coherent fluids such as plumes using small unmanned aircraft systems (sUAS). In the CAOS approach, two classes of sUAS, one remote the other in-situ, implement a dynamic data-driven mapping system by closing the loop between Modeling, Estimation, Sampling, Planning and Control (MESPAC). The continually gathered measurements are assimilated to produce maps/analyses which also guide the sUAS network to adaptively resample the environment. Rather than scan the volume in fixed Eulerian or Lagrangian flight plans, the adaptive nature of the sampling process enables objectives for efficiency and resilience to be incorporated. Modeling includes realtime prediction using two types of reduced models, one based on nowcasting remote observations of plume tracer using scale-cascaded alignment, and another based on dynamically-deformable EOF/POD developed for coherent structures. Ensemble-based Information-theoretic machine learning approaches are used for the highly non-linear/non-Gaussian state/parameter estimation, and for planning. Control of the sUAS is based on model reference control coupled with hierarchical PID. MESPAC is implemented in part on a SkyCandy platform, and implements an airborne mesh that provides instantaneous situational awareness and redundant communication to an operating fleet. SkyCandy is deployed on Itzamna Aero's I9X/W UAS with low-cost sensors, and is currently being used to study the Popocatepetl volcano. Results suggest that operational communities can deploy low-cost sUAS to systematically monitor whilst optimizing for efficiency/maximizing resilience. The CAOS methodology is applicable to many other environments where coherent structures are present in the background. More information can be found at caos.mit.edu.
The next generation of low-cost personal air quality sensors for quantitative exposure monitoring
NASA Astrophysics Data System (ADS)
Piedrahita, R.; Xiang, Y.; Masson, N.; Ortega, J.; Collier, A.; Jiang, Y.; Li, K.; Dick, R.; Lv, Q.; Hannigan, M.; Shang, L.
2014-03-01
Advances in embedded systems and low-cost gas sensors are enabling a new wave of low cost air quality monitoring tools. Our team has been engaged in the development of low-cost wearable air quality monitors (M-Pods) using the Arduino platform. The M-Pods use commercially available metal oxide semiconductor (MOx) sensors to measure CO, O3, NO2, and total VOCs, and NDIR sensors to measure CO2. MOx sensors are low in cost and show high sensitivity near ambient levels; however they display non-linear output signals and have cross sensitivity effects. Thus, a quantification system was developed to convert the MOx sensor signals into concentrations. Two deployments were conducted at a regulatory monitoring station in Denver, Colorado. M-Pod concentrations were determined using laboratory calibration techniques and co-location calibrations, in which we place the M-Pods near regulatory monitors to then derive calibration function coefficients using the regulatory monitors as the standard. The form of the calibration function was derived based on laboratory experiments. We discuss various techniques used to estimate measurement uncertainties. A separate user study was also conducted to assess personal exposure and M-Pod reliability. In this study, 10 M-Pods were calibrated via co-location multiple times over 4 weeks and sensor drift was analyzed with the result being a calibration function that included drift. We found that co-location calibrations perform better than laboratory calibrations. Lab calibrations suffer from bias and difficulty in covering the necessary parameter space. During co-location calibrations, median standard errors ranged between 4.0-6.1 ppb for O3, 6.4-8.4 ppb for NO2, 0.28-0.44 ppm for CO, and 16.8 ppm for CO2. Median signal to noise (S/N) ratios for the M-Pod sensors were higher for M-Pods than the regulatory instruments: for NO2, 3.6 compared to 23.4; for O3, 1.4 compared to 1.6; for CO, 1.1 compared to 10.0; and for CO2, 42.2 compared to 300-500. The user study provided trends and location-specific information on pollutants, and affected change in user behavior. The study demonstrated the utility of the M-Pod as a tool to assess personal exposure.
Continuous 30-day measurements utilizing the monkey metabolism pod. [study of weightlessness effects
NASA Technical Reports Server (NTRS)
Pace, N.; Kodama, A. M.; Mains, R. C.; Rahlmann, D. F.; Grunbaum, B. W.
1977-01-01
A fiberglass system was previously described, using which quantitative physiological measurements could be made to study the effects of weightlessness on 10 to 14 kg adult monkeys maintained in comfortable restraint under space flight conditions. Recent improvements in the system have made it possible to obtain continuous measurements of respiratory gas exchange, cardiovascular function, and mineral balance for periods of up to 30 days on pig-tailed monkeys. It has also been possible to operate two pods which share one set of instrumentation, thereby permitting simultaneous measurements to be made on two animals by commutating signal outputs from the pods. In principle, more than two pods could be operated in this fashion. The system is compatible with Spacelab design. Representative physiological data from ground tests of the system are presented.
A trust-region algorithm for the optimization of PSA processes using reduced-order modeling
DOE Office of Scientific and Technical Information (OSTI.GOV)
Agarwal, A.; Biegler, L.; Zitney, S.
2009-01-01
The last few decades have seen a considerable increase in the applications of adsorptive gas separation technologies, such as pressure swing adsorption (PSA); the applications range from bulk separations to trace contaminant removal. PSA processes are based on solid-gas equilibrium and operate under periodic transient conditions [1]. Bed models for these processes are therefore defined by coupled nonlinear partial differential and algebraic equations (PDAEs) distributed in space and time with periodic boundary conditions that connect the processing steps together and high nonlinearities arising from non-isothermal effects and nonlinear adsorption isotherms. As a result, the optimization of such systems for eithermore » design or operation represents a significant computational challenge to current nonlinear programming algorithms. Model reduction is a powerful methodology that permits systematic generation of cost-efficient low-order representations of large-scale systems that result from discretization of such PDAEs. In particular, low-dimensional approximations can be obtained from reduced order modeling (ROM) techniques based on proper orthogonal decomposition (POD) and can be used as surrogate models in the optimization problems. In this approach, a representative ensemble of solutions of the dynamic PDAE system is constructed by solving a higher-order discretization of the model using the method of lines, followed by the application of Karhunen-Loeve expansion to derive a small set of empirical eigenfunctions (POD modes). These modes are used as basis functions within a Galerkin's projection framework to derive a low-order DAE system that accurately describes the dominant dynamics of the PDAE system. This approach leads to a DAE system of significantly lower order, thus replacing the one obtained from spatial discretization before and making optimization problem computationally efficient [2]. The ROM methodology has been successfully applied to a 2-bed 4-step PSA process used for separating a hydrogen-methane mixture in [3]. The reduced order model developed was successfully used to optimize this process to maximize hydrogen recovery within a trust-region. We extend this approach in this work to develop a rigorous trust-region algorithm for ROM-based optimization of PSA processes. The trust-region update rules and sufficient decrease condition for the objective is used to determine the size of the trust-region. Based on the decrease in the objective function and error in the ROM, a ROM updation strategy is designed [4, 5]. The inequalities and bounds are handled in the algorithm using exact penalty formulation, and a non-smooth trust-region algorithm by Conn et al. [6] is used to handle non-differentiability. To ensure that the first order consistency condition is met and the optimum obtained from ROM-based optimization corresponds to the optimum of the original problem, a scaling function, such as one proposed by Alexandrov et al. [7], is incorporated in the objective function. Such error control mechanism is also capable of handling numerical inconsistencies such as unphysical oscillations in the state variable profiles. The proposed methodology is applied to optimize a PSA process to concentrate CO{sub 2} from a nitrogen-carbon dioxide mixture. As in [3], separate ROMs are developed for each operating step with different POD modes for each state variable. Numerical results will be presented for optimization case studies which involve maximizing CO{sub 2} recovery, feed throughput or minimizing overall power consumption.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Paulsson, Bjorn N.P.
2015-02-28
To address the critical site characterization and monitoring needs for CCS programs, US Department of Energy (DOE) awarded Paulsson, Inc. in 2010 a contract to design, build and test a fiber optic based ultra-large bandwidth clamped borehole seismic vector array capable of deploying up to one thousand 3C sensor pods suitable for deployment into high temperature and high pressure boreholes. Paulsson, Inc. has completed a design or a unique borehole seismic system consisting of a novel drill pipe based deployment system that includes a hydraulic clamping mechanism for the sensor pods, a new sensor pod design and most important –more » a unique fiber optic seismic vector sensor with technical specifications and capabilities that far exceed the state of the art seismic sensor technologies. These novel technologies were all applied to the new borehole seismic system. In combination these technologies will allow for the deployment of up to 1,000 3C sensor pods in vertical, deviated or horizontal wells. Laboratory tests of the fiber optic seismic vector sensors developed during this project have shown that the new borehole seismic sensor technology is capable of generating outstanding high vector fidelity data with extremely large bandwidth: 0.01 – 6,000 Hz. Field tests have shown that the system can record events at magnitudes much smaller than M-2.3 at frequencies up to 2,000 Hz. The sensors have also proved to be about 100 times more sensitive than the regular coil geophones that are used in borehole seismic systems today. The fiber optic seismic sensors have furthermore been qualified to operate at temperatures over 300°C (572°F). The fibers used for the seismic sensors in the system are used to record Distributed Temperature Sensor (DTS) data allowing additional value added data to be recorded simultaneously with the seismic vector sensor data.« less
A flexible, highly sensitive catheter for high resolution manometry based on in-fibre Bragg gratings
NASA Astrophysics Data System (ADS)
Bueley, Christopher; Wild, Peter M.
2013-09-01
This work presents a fibre optic-based flexible catheter for high resolution manometry (HRM), with sensing pods located at a pitch of 10 mm and an overall diameter of 2.8 mm. In-fibre Bragg gratings act as the sensing elements within these sensing pods. Hydrodynamic pressure resolution of 0.2 mmHg is demonstrated in conjunction with insensitivity to occlusion pressure. This result is significant in the context of HRM where independent measurement of hydrodynamic pressure is clinically relevant. The sensing system is compact, robust and flexible. Crosstalk between individual sensors is characterized and a compensation scheme is developed and validated.
POD analysis of flow over a backward-facing step forced by right-angle-shaped plasma actuator.
Wang, Bin; Li, Huaxing
2016-01-01
This study aims to present flow control over the backward-facing step with specially designed right-angle-shaped plasma actuator and analyzed the influence of various scales of flow structures on the Reynolds stress through snapshot proper orthogonal decomposition (POD). 2D particle image velocimetry measurements were conducted on region (x/h = 0-2.25) and reattachment zone in the x-y plane over the backward-facing step at a Reynolds number of Re h = 27,766 (based on step height [Formula: see text] and free stream velocity [Formula: see text]. The separated shear layer was excited by specially designed right-angle-shaped plasma actuator under the normalized excitation frequency St h ≈ 0.345 along the 45° direction. The spatial distribution of each Reynolds stress component was reconstructed using an increasing number of POD modes. The POD analysis indicated that the flow dynamic downstream of the step was dominated by large-scale flow structures, which contributed to streamwise Reynolds stress and Reynolds shear stress. The intense Reynolds stress localized to a narrow strip within the shear layer was mainly affected by small-scale flow structures, which were responsible for the recovery of the Reynolds stress peak. With plasma excitation, a significant increase was obtained in the vertical Reynolds stress peak. Under the dimensionless frequencies St h ≈ 0.345 and [Formula: see text] which are based on the step height and momentum thickness, the effectiveness of the flow control forced by the plasma actuator along the 45° direction was ordinary. Only the vertical Reynolds stress was significantly affected.
Swain, Thomas A; McGwin, Gerald; Griffin, Russell
2016-12-01
Previous studies have reported that children are at risk of severe injuries from exposure to laundry detergent pods. For the first time, this study sought to compare demographic and exposure characteristics and risk among children exposed to pod and non-pod laundry detergents presenting to emergency departments (EDs). Data from the National Electronic Injury Surveillance System (NEISS) from 2012-2014 were used. All observations with injuries involving laundry detergent (NEISS code 0949) were included in this study. The χ 2 test was used for bivariate analysis and logistic regression was used to determine the OR and 95% CI of hospitalisation for pod related versus non-pod laundry detergent exposures. From 2012-2014, there were an estimated 26 062 non-pod and 9814 pod laundry detergent related exposures among those aged 18 years and younger. For pod detergent, children aged 0-5 years had the most injuries. Poisoning (71.3%) was the most common diagnosis for pod detergent while contact dermatitis (72.2%) was most common for non-pod detergent. Hospitalisation occurred in 12.5% of pod detergent cases and just 3.0% of non-pod cases. Compared with non-pod detergent, those exposed to pod detergent were 4 times as likely to be hospitalised (OR 4.02; 95% CI 1.96 to 8.24). A greater effort should be made to appropriately educate the public about the dangers of laundry detergents, specifically pods, so a safe home environment can be established. While new regulations such as childproof containers, opaque packaging, and less appealing and colourful pods could reduce the number of pod related ED visits for children, caregivers should store detergents, along with other chemicals, in a secure location where children cannot easily access them. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Precise orbit determination of the Fengyun-3C satellite using onboard GPS and BDS observations
NASA Astrophysics Data System (ADS)
Li, Min; Li, Wenwen; Shi, Chuang; Jiang, Kecai; Guo, Xiang; Dai, Xiaolei; Meng, Xiangguang; Yang, Zhongdong; Yang, Guanglin; Liao, Mi
2017-11-01
The GNSS Occultation Sounder instrument onboard the Chinese meteorological satellite Fengyun-3C (FY-3C) tracks both GPS and BDS signals for orbit determination. One month's worth of the onboard dual-frequency GPS and BDS data during March 2015 from the FY-3C satellite is analyzed in this study. The onboard BDS and GPS measurement quality is evaluated in terms of data quantity as well as code multipath error. Severe multipath errors for BDS code ranges are observed especially for high elevations for BDS medium earth orbit satellites (MEOs). The code multipath errors are estimated as piecewise linear model in 2{°}× 2{°} grid and applied in precise orbit determination (POD) calculations. POD of FY-3C is firstly performed with GPS data, which shows orbit consistency of approximate 2.7 cm in 3D RMS (root mean square) by overlap comparisons; the estimated orbits are then used as reference orbits for evaluating the orbit precision of GPS and BDS combined POD as well as BDS-based POD. It is indicated that inclusion of BDS geosynchronous orbit satellites (GEOs) could degrade POD precision seriously. The precisions of orbit estimates by combined POD and BDS-based POD are 3.4 and 30.1 cm in 3D RMS when GEOs are involved, respectively. However, if BDS GEOs are excluded, the combined POD can reach similar precision with respect to GPS POD, showing orbit differences about 0.8 cm, while the orbit precision of BDS-based POD can be improved to 8.4 cm. These results indicate that the POD performance with onboard BDS data alone can reach precision better than 10 cm with only five BDS inclined geosynchronous satellite orbit satellites and three MEOs. As the GNOS receiver can only track six BDS satellites for orbit positioning at its maximum channel, it can be expected that the performance of POD with onboard BDS data can be further improved if more observations are generated without such restrictions.
Learning a detection map for a network of unattended ground sensors.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nguyen, Hung D.; Koch, Mark William
2010-03-01
We have developed algorithms to automatically learn a detection map of a deployed sensor field for a virtual presence and extended defense (VPED) system without apriori knowledge of the local terrain. The VPED system is an unattended network of sensor pods, with each pod containing acoustic and seismic sensors. Each pod has the ability to detect and classify moving targets at a limited range. By using a network of pods we can form a virtual perimeter with each pod responsible for a certain section of the perimeter. The site's geography and soil conditions can affect the detection performance of themore » pods. Thus, a network in the field may not have the same performance as a network designed in the lab. To solve this problem we automatically estimate a network's detection performance as it is being installed at a site by a mobile deployment unit (MDU). The MDU will wear a GPS unit, so the system not only knows when it can detect the MDU, but also the MDU's location. In this paper, we demonstrate how to handle anisotropic sensor-configurations, geography, and soil conditions.« less
NASA Technical Reports Server (NTRS)
Generazio, Edward R.
2011-01-01
The capability of an inspection system is established by applications of various methodologies to determine the probability of detection (POD). One accepted metric of an adequate inspection system is that for a minimum flaw size and all greater flaw sizes, there is 0.90 probability of detection with 95% confidence (90/95 POD). Directed design of experiments for probability of detection (DOEPOD) has been developed to provide an efficient and accurate methodology that yields estimates of POD and confidence bounds for both Hit-Miss or signal amplitude testing, where signal amplitudes are reduced to Hit-Miss by using a signal threshold Directed DOEPOD uses a nonparametric approach for the analysis or inspection data that does require any assumptions about the particular functional form of a POD function. The DOEPOD procedure identifies, for a given sample set whether or not the minimum requirement of 0.90 probability of detection with 95% confidence is demonstrated for a minimum flaw size and for all greater flaw sizes (90/95 POD). The DOEPOD procedures are sequentially executed in order to minimize the number of samples needed to demonstrate that there is a 90/95 POD lower confidence bound at a given flaw size and that the POD is monotonic for flaw sizes exceeding that 90/95 POD flaw size. The conservativeness of the DOEPOD methodology results is discussed. Validated guidelines for binomial estimation of POD for fracture critical inspection are established.
Reduced order modeling and active flow control of an inlet duct
NASA Astrophysics Data System (ADS)
Ge, Xiaoqing
Many aerodynamic applications require the modeling of compressible flows in or around a body, e.g., the design of aircraft, inlet or exhaust duct, wind turbines, or tall buildings. Traditional methods use wind tunnel experiments and computational fluid dynamics (CFD) to investigate the spatial and temporal distribution of the flows. Although they provide a great deal of insight into the essential characteristics of the flow field, they are not suitable for control analysis and design due to the high physical/computational cost. Many model reduction methods have been studied to reduce the complexity of the flow model. There are two main approaches: linearization based input/output modeling and proper orthogonal decomposition (POD) based model reduction. The former captures mostly the local behavior near a steady state, which is suitable to model laminar flow dynamics. The latter obtains a reduced order model by projecting the governing equation onto an "optimal" subspace and is able to model complex nonlinear flow phenomena. In this research we investigate various model reduction approaches and compare them in flow modeling and control design. We propose an integrated model-based control methodology and apply it to the reduced order modeling and active flow control of compressible flows within a very aggressive (length to exit diameter ratio, L/D, of 1.5) inlet duct and its upstream contraction section. The approach systematically applies reduced order modeling, estimator design, sensor placement and control design to improve the aerodynamic performance. The main contribution of this work is the development of a hybrid model reduction approach that attempts to combine the best features of input/output model identification and POD method. We first identify a linear input/output model by using a subspace algorithm. We next project the difference between CFD response and the identified model response onto a set of POD basis. This trajectory is fit to a nonlinear dynamical model to augment the linear input/output model. Thus, the full system is decomposed into a dominant linear subsystem and a low order nonlinear subsystem. The hybrid model is then used for control design and compared with other modeling methods in CFD simulations. Numerical results indicate that the hybrid model accurately predicts the nonlinear behavior of the flow for a 2D diffuser contraction section model. It also performs best in terms of feedback control design and learning control. Since some outputs of interest (e.g., the AIP pressure recovery) are not observable during normal operations, static and dynamic estimators are designed to recreate the information from available sensor measurements. The latter also provides a state estimation for feedback controller. Based on the reduced order models and estimators, different controllers are designed to improve the aerodynamic performance of the contraction section and inlet duct. The integrated control methodology is evaluated with CFD simulations. Numerical results demonstrate the feasibility and efficacy of the active flow control based on reduced order models. Our reduced order models not only generate a good approximation of the nonlinear flow dynamics over a wide input range, but also help to design controllers that significantly improve the flow response. The tools developed for model reduction, estimator and control design can also be applied to wind tunnel experiment.
DORIS-based point mascons for the long term stability of precise orbit solutions
NASA Astrophysics Data System (ADS)
Cerri, L.; Lemoine, J. M.; Mercier, F.; Zelensky, N. P.; Lemoine, F. G.
2013-08-01
In recent years non-tidal Time Varying Gravity (TVG) has emerged as the most important contributor in the error budget of Precision Orbit Determination (POD) solutions for altimeter satellites' orbits. The Gravity Recovery And Climate Experiment (GRACE) mission has provided POD analysts with static and time-varying gravity models that are very accurate over the 2002-2012 time interval, but whose linear rates cannot be safely extrapolated before and after the GRACE lifespan. One such model based on a combination of data from GRACE and Lageos from 2002-2010, is used in the dynamic POD solutions developed for the Geophysical Data Records (GDRs) of the Jason series of altimeter missions and the equivalent products from lower altitude missions such as Envisat, Cryosat-2, and HY-2A. In order to accommodate long-term time-variable gravity variations not included in the background geopotential model, we assess the feasibility of using DORIS data to observe local mass variations using point mascons. In particular, we show that the point-mascon approach can stabilize the geographically correlated orbit errors which are of fundamental interest for the analysis of regional Mean Sea Level trends based on altimeter data, and can therefore provide an interim solution in the event of GRACE data loss. The time series of point-mass solutions for Greenland and Antarctica show good agreement with independent series derived from GRACE data, indicating a mass loss at rate of 210 Gt/year and 110 Gt/year respectively.
Sentinel-1A - First precise orbit determination results
NASA Astrophysics Data System (ADS)
Peter, H.; Jäggi, A.; Fernández, J.; Escobar, D.; Ayuga, F.; Arnold, D.; Wermuth, M.; Hackel, S.; Otten, M.; Simons, W.; Visser, P.; Hugentobler, U.; Féménias, P.
2017-09-01
Sentinel-1A is the first satellite of the European Copernicus programme. Equipped with a Synthetic Aperture Radar (SAR) instrument the satellite was launched on April 3, 2014. Operational since October 2014 the satellite delivers valuable data for more than two years. The orbit accuracy requirements are given as 5 cm in 3D. In order to fulfill this stringent requirement the precise orbit determination (POD) is based on the dual-frequency GPS observations delivered by an eight-channel GPS receiver. The Copernicus POD (CPOD) Service is in charge of providing the orbital and auxiliary products required by the PDGS (Payload Data Ground Segment). External orbit validation is regularly performed by comparing the CPOD Service orbits to orbit solutions provided by POD expert members of the Copernicus POD Quality Working Group (QWG). The orbit comparisons revealed systematic orbit offsets mainly in radial direction (approx. 3 cm). Although no independent observation technique (e.g. DORIS, SLR) is available to validate the GPS-derived orbit solutions, comparisons between the different antenna phase center variations and different reduced-dynamic orbit determination approaches used in the various software packages helped to detect the cause of the systematic offset. An error in the given geometry information about the satellite has been found. After correction of the geometry the orbit validation shows a significant reduction of the radial offset to below 5 mm. The 5 cm orbit accuracy requirement in 3D is fulfilled according to the results of the orbit comparisons between the different orbit solutions from the QWG.
NASA Technical Reports Server (NTRS)
Hughitt, Brian; Generazio, Edward (Principal Investigator); Nichols, Charles; Myers, Mika (Principal Investigator); Spencer, Floyd (Principal Investigator); Waller, Jess (Principal Investigator); Wladyka, Jordan (Principal Investigator); Aldrin, John; Burke, Eric; Cerecerez, Laura;
2016-01-01
NASA-STD-5009 requires that successful flaw detection by NDE methods be statistically qualified for use on fracture critical metallic components, but does not standardize practices. This task works towards standardizing calculations and record retention with a web-based tool, the NNWG POD Standards Library or NPSL. Test methods will also be standardized with an appropriately flexible appendix to -5009 identifying best practices. Additionally, this appendix will describe how specimens used to qualify NDE systems will be cataloged, stored and protected from corrosion, damage, or loss.
Integrated Cryogenic Experiment (ICE) microsphere investigation
NASA Technical Reports Server (NTRS)
Spradley, I.; Read, D.
1989-01-01
The main objective is to determine the performance of microsphere insulation in a 0-g environment and compare its performance to reference insulations such as multilayer insulation. The Lockheed Helium Extended-Life Dewar (HELD) is used to provide superfluid-helium cold sink for the experiment. The use of HELD allows the low-g dynamic properties of Passive Orbital Disconnect Struts (PODS) to be characterized and provides a flight demonstration of the PODS system. The thermal performance of microspheres in 1 and 0 g was predicted, a flight experiment was designed to determine microsphere thermal performance, and the interface was also designed between the experimental package and the shuttle through HELD and the Hitchhiker-M carrier. A single test cell was designed and fabricated. The cell was filled with uncoated glass microspheres and tested with a liquid-nitrogen cold sink. The data were found to agree with predictions of microsphere performance in 1 g.
Low Frequency Radioastronomy at Moon: possible approach and architecture
NASA Astrophysics Data System (ADS)
Skalsky, A.; Mogilevsky, M.; Nazarov, V.; Nazirov, R.; Batanov, O.; Sadovski, A.
2009-04-01
The Moon, the Earth's neighbor, attracts an attention as a celestial body, as a source for mineral and other resources and as a possible base for fundamental scientific researches. The conducting ionosphere of Earth completely shields radioemissions coming from outer space and propagating at frequencies below a few MHz. In contrary, the Moon possessing a week atmosphereionosphere around its surface seems to be a perfect base for carrying out measurements of low frequency radio emissions originated from the space. The radio facility deployed at Moon's surface seems to be a powerful tool for various fundamental space researches related to astrophysics, solar system and magnetospheric investigations. The most intriguing objective is a search of terrestrial-like planets in the exosolar system, i.e. planets possessing the intrinsic magnetic fields and developed magnetospheres which interaction with the star wind results in generation of radioemissions (similar to AKR radiation of the terrestrial magnetosphere). Creating the infrastructure of antennas (sensors) on Moon's surface is planned for reaching the described goals. Ideology of such infrastructure (which may be treated as macro-instrument) is closely to SensorWeb approach. The different sensors are collected to unified platforms (PODs in terms of SensorWeb) which provide omni-and bidirectional information flows between PODs. Thus a set of sensors is integrated self-organizing amorphous organism on the base of wireless network. It increases reliability of the research complex and allows quick reconfiguring and adopting it for different investigation tasks. For additional redundancy and openness of the complex at least some PODs will support not only inter-PODs protocol but IEEE 802.16 Wireless LAN standard used in NASA Lunar Communication and Navigation Architecture also. The paper presents a possible approach to the development of the radio facility deployed at Moon's surface, its implementation for various fundamental researches
Integrated Solution for Physical Activity Monitoring Based on Mobile Phone and PC.
Lee, Mi Hee; Kim, Jungchae; Jee, Sun Ha; Yoo, Sun Kook
2011-03-01
This study is part of the ongoing development of treatment methods for metabolic syndrome (MS) project, which involves monitoring daily physical activity. In this study, we have focused on detecting walking activity from subjects which includes many other physical activities such as standing, sitting, lying, walking, running, and falling. Specially, we implemented an integrated solution for various physical activities monitoring using a mobile phone and PC. We put the iPod touch has built in a tri-axial accelerometer on the waist of the subjects, and measured change in acceleration signal according to change in ambulatory movement and physical activities. First, we developed of programs that are aware of step counts, velocity of walking, energy consumptions, and metabolic equivalents based on iPod. Second, we have developed the activity recognition program based on PC. iPod synchronization with PC to transmit measured data using iPhoneBrowser program. Using the implemented system, we analyzed change in acceleration signal according to the change of six activity patterns. We compared results of the step counting algorithm with different positions. The mean accuracy across these tests was 99.6 ± 0.61%, 99.1 ± 0.87% (right waist location, right pants pocket). Moreover, six activities recognition was performed using Fuzzy c means classification algorithm recognized over 98% accuracy. In addition we developed of programs that synchronization of data between PC and iPod for long-term physical activity monitoring. This study will provide evidence on using mobile phone and PC for monitoring various activities in everyday life. The next step in our system will be addition of a standard value of various physical activities in everyday life such as household duties and a health guideline how to select and plan exercise considering one's physical characteristics and condition.
Paul, Sarbajit; Chang, Junghwan
2017-01-01
This paper presents a design approach for a magnetic sensor module to detect mover position using the proper orthogonal decomposition-dynamic mode decomposition (POD-DMD)-based nonlinear parametric model order reduction (PMOR). The parameterization of the sensor module is achieved by using the multipolar moment matching method. Several geometric variables of the sensor module are considered while developing the parametric study. The operation of the sensor module is based on the principle of the airgap flux density distribution detection by the Hall Effect IC. Therefore, the design objective is to achieve a peak flux density (PFD) greater than 0.1 T and total harmonic distortion (THD) less than 3%. To fulfill the constraint conditions, the specifications for the sensor module is achieved by using POD-DMD based reduced model. The POD-DMD based reduced model provides a platform to analyze the high number of design models very fast, with less computational burden. Finally, with the final specifications, the experimental prototype is designed and tested. Two different modes, 90° and 120° modes respectively are used to obtain the position information of the linear motor mover. The position information thus obtained are compared with that of the linear scale data, used as a reference signal. The position information obtained using the 120° mode has a standard deviation of 0.10 mm from the reference linear scale signal, whereas the 90° mode position signal shows a deviation of 0.23 mm from the reference. The deviation in the output arises due to the mechanical tolerances introduced into the specification during the manufacturing process. This provides a scope for coupling the reliability based design optimization in the design process as a future extension. PMID:28671580
Paul, Sarbajit; Chang, Junghwan
2017-07-01
This paper presents a design approach for a magnetic sensor module to detect mover position using the proper orthogonal decomposition-dynamic mode decomposition (POD-DMD)-based nonlinear parametric model order reduction (PMOR). The parameterization of the sensor module is achieved by using the multipolar moment matching method. Several geometric variables of the sensor module are considered while developing the parametric study. The operation of the sensor module is based on the principle of the airgap flux density distribution detection by the Hall Effect IC. Therefore, the design objective is to achieve a peak flux density (PFD) greater than 0.1 T and total harmonic distortion (THD) less than 3%. To fulfill the constraint conditions, the specifications for the sensor module is achieved by using POD-DMD based reduced model. The POD-DMD based reduced model provides a platform to analyze the high number of design models very fast, with less computational burden. Finally, with the final specifications, the experimental prototype is designed and tested. Two different modes, 90° and 120° modes respectively are used to obtain the position information of the linear motor mover. The position information thus obtained are compared with that of the linear scale data, used as a reference signal. The position information obtained using the 120° mode has a standard deviation of 0.10 mm from the reference linear scale signal, whereas the 90° mode position signal shows a deviation of 0.23 mm from the reference. The deviation in the output arises due to the mechanical tolerances introduced into the specification during the manufacturing process. This provides a scope for coupling the reliability based design optimization in the design process as a future extension.
2004-04-21
KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, the left-hand Orbital Maneuvering System (OMS) pod (seen from the back) is lifted off its transporter. The OMS pod will be installed on the orbiter Discovery. The Orbital Maneuvering System provides the thrust for orbit insertion, orbit circularization, orbit transfer, rendezvous, deorbit, abort to orbit and abort once around. It can provide up to 1,000 pounds of propellant to the aft reaction control system. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers.
2004-04-21
KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, the left-hand Orbital Maneuvering System (OMS) pod is lifted at an angle from the transporter below. The OMS pod will be installed on the orbiter Discovery. The Orbital Maneuvering System provides the thrust for orbit insertion, orbit circularization, orbit transfer, rendezvous, deorbit, abort to orbit and abort once around. It can provide up to 1,000 pounds of propellant to the aft reaction control system. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers.
2004-04-21
KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, workers check the lifting of the left-hand Orbital Maneuvering System (OMS) pod. The OMS pod will be installed on the orbiter Discovery. The Orbital Maneuvering System provides the thrust for orbit insertion, orbit circularization, orbit transfer, rendezvous, deorbit, abort to orbit and abort once around. It can provide up to 1,000 pounds of propellant to the aft reaction control system. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers.
2004-04-21
KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, the left-hand Orbital Maneuvering System (OMS) pod (seen from the front) is lifted off its transporter. The OMS pod will be installed on the orbiter Discovery. The Orbital Maneuvering System provides the thrust for orbit insertion, orbit circularization, orbit transfer, rendezvous, deorbit, abort to orbit and abort once around. It can provide up to 1,000 pounds of propellant to the aft reaction control system. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers.
2017-10-31
At Vandenberg Air Force Base in California, a Poly Picosatellite Orbital Deployer, or P-POD, container is installed on the Joint Polar Satellite System-1, or JPSS-1, spacecraft. P-PODS are auxiliary payloads launched aboard NASA expendable launch vehicles carrying up to three small CubeSats. The small cube-shaped satellites are part of NASA’s Educational Launch of Nanosatellite, or ELaNa, missions. The small payloads are designed and built by students from high school-level classes up to college and university students. JPSS is the first in a series of four next-generation environmental satellites in a collaborative program between the NOAA and NASA. Liftoff from Vandenberg's Space Launch Compex-2 atop a United Launch Alliance Delta II rocket is scheduled for 1:47 a.m. PST (4:47 a.m. EST), on Nov. 14, 2017.
2017-10-31
At Vandenberg Air Force Base in California, technicians and engineers prepare to install a Poly Picosatellite Orbital Deployer, or P-POD, container on the Joint Polar Satellite System-1, or JPSS-1, spacecraft. P-PODS are auxiliary payloads launched aboard NASA expendable launch vehicles carrying up to three small CubeSats. The small cube-shaped satellites are part of NASA’s Educational Launch of Nanosatellite, or ELaNa, missions. The small payloads are designed and built by students from high school-level classes up to college and university students. JPSS is the first in a series of four next-generation environmental satellites in a collaborative program between the NOAA and NASA. Liftoff from Vandenberg's Space Launch Compex-2 atop a United Launch Alliance Delta II rocket is scheduled for 1:47 a.m. PST (4:47 a.m. EST), on Nov. 14, 2017.
2017-10-31
At Vandenberg Air Force Base in California, technicians and engineers prepare a Poly Picosatellite Orbital Deployer, or P-POD, container for installation on the Joint Polar Satellite System-1, or JPSS-1, spacecraft. P-PODS are auxiliary payloads launched aboard NASA expendable launch vehicles carrying up to three small CubeSats. The small cube-shaped satellites are part of NASA’s Educational Launch of Nanosatellite, or ELaNa, missions. The small payloads are designed and built by students from high school-level classes up to college and university students. JPSS is the first in a series of four next-generation environmental satellites in a collaborative program between the NOAA and NASA. Liftoff from Vandenberg's Space Launch Compex-2 atop a United Launch Alliance Delta II rocket is scheduled for 1:47 a.m. PST (4:47 a.m. EST), on Nov. 14, 2017.
NASA Astrophysics Data System (ADS)
Jin, Yulin; Lu, Kuan; Hou, Lei; Chen, Yushu
2017-12-01
The proper orthogonal decomposition (POD) method is a main and efficient tool for order reduction of high-dimensional complex systems in many research fields. However, the robustness problem of this method is always unsolved, although there are some modified POD methods which were proposed to solve this problem. In this paper, a new adaptive POD method called the interpolation Grassmann manifold (IGM) method is proposed to address the weakness of local property of the interpolation tangent-space of Grassmann manifold (ITGM) method in a wider parametric region. This method is demonstrated here by a nonlinear rotor system of 33-degrees of freedom (DOFs) with a pair of liquid-film bearings and a pedestal looseness fault. The motion region of the rotor system is divided into two parts: simple motion region and complex motion region. The adaptive POD method is compared with the ITGM method for the large and small spans of parameter in the two parametric regions to present the advantage of this method and disadvantage of the ITGM method. The comparisons of the responses are applied to verify the accuracy and robustness of the adaptive POD method, as well as the computational efficiency is also analyzed. As a result, the new adaptive POD method has a strong robustness and high computational efficiency and accuracy in a wide scope of parameter.
Teng, K; Xiao, G Z; Guo, W E; Yuan, J B; Li, J; Chao, Y H; Han, L B
2016-05-23
Peroxidases (PODs) are enzymes that play important roles in catalyzing the reduction of H2O2 and the oxidation of various substrates. They function in many different and important biological processes, such as defense mechanisms, immune responses, and pathogeny. The POD genes have been cloned and identified in many plants, but their function in alfalfa (Medicago sativa L.) is not known, to date. Based on the POD gene sequence (GenBank accession No. L36157.1), we cloned the POD gene in alfalfa, which was named MsPOD. MsPOD expression increased with increasing H2O2. The gene was expressed in all of the tissues, including the roots, stems, leaves, and flowers, particularly in stems and leaves under light/dark conditions. A subcellular analysis showed that MsPOD was localized outside the cells. Transgenic Arabidopsis with MsPOD exhibited increased resistance to H2O2 and NaCl. Moreover, POD activity in the transgenic plants was significantly higher than that in wild-type Arabidopsis. These results show that MsPOD plays an important role in resistance to H2O2 and NaCl.
On the POD based reduced order modeling of high Reynolds flows
NASA Astrophysics Data System (ADS)
Behzad, Fariduddin; Helenbrook, Brian; Ahmadi, Goodarz
2012-11-01
Reduced-order modeling (ROM) of a high Reynolds fluid flow using the proper orthogonal decomposition (POD) was studied. Particular attention was given to incompressible, unsteady flow over a two-dimensional NACA0015 airfoil. The Reynolds number is 105 and the angle of attacked of the airfoil is 12°. For DNS solution, hp-finite element method is employed to drive flow samples from which the POD modes are extracted. Particular attention is paid on two issues. First, the stability of POD-ROM resimulation of the turbulent flow is studied. High Reynolds flow contains a lot of fluctuating modes. So, to reach a certain amount of error, more POD modes are needed and the effect of truncation of POD modes is more important. Second, the role of convergence rate on the results of POD. Due to complexity of the flow, convergence of the governing equations is more difficult and the influences of weak convergence appear in the results of POD-ROM. For each issue, the capability of the POD-ROM is assessed in terms of predictions quality of times upon which the POD model was derived. The results are compared with DNS solution and the accuracy and efficiency of different cases are evaluated.
Assessment of molecular contamination in mask pod
NASA Astrophysics Data System (ADS)
Foray, Jean Marie; Dejaune, Patrice; Sergent, Pierre; Gough, Stuart; Cheung, D.; Davenet, Magali; Favre, Arnaud; Rude, C.; Trautmann, T.; Tissier, Michel; Fontaine, H.; Veillerot, M.; Avary, K.; Hollein, I.; Lerit, R.
2008-04-01
Context/ study Motivation: Contamination and especially Airbone Molecular Contamination (AMC) is a critical issue for mask material flow with a severe and fairly unpredictable risk of induced contamination and damages especially for 193 nm lithography. It is therefore essential to measure, to understand and then try to reduce AMC in mask environment. Mask material flow was studied in a global approach by a pool of European partners, especially within the frame of European MEDEA+ project, so called "MUSCLE". This paper deals with results and assessment of mask pod environment in term of molecular contamination in a first step, then in a second step preliminary studies to reduce mask pod influence and contamination due to material out gassing. Approach and techniques: A specific assessment of environmental / molecular contamination along the supply chain was performed by all partners. After previous work presented at EMLC 07, further studies were performed on real time contamination measurement pod at different sites locations (including Mask manufacturing site, blank manufacturing sites, IC fab). Studies were linked to the main critical issues: cleaning, storage, handling, materials and processes. Contamination measurement campaigns were carried out along the mask supply chain using specific Adixen analyzer in order to monitor in real time organic contaminants (ppb level) in mask pods. Key results would be presented: VOC, AMC and humidity level on different kinds of mask carriers, impact of basic cleaning on pod outgassing measurement (VOC, NH3), and process influence on pod contamination... In a second step, preliminary specific pod conditioning studies for better pod environment were performed based on Adixen vacuum process. Process influence had been experimentally measured in term of molecular outgassing from mask pods. Different AMC experimental characterization methods had been carried out leading to results on a wide range of organic and inorganic contaminants: by inline techniques based on Adixen humidity, also VOC and organic sensors, together by off-line techniques already used in the extensive previous mask pods benchmark (TD-GCMS & Ionic Chromatography). Humidity and VOC levels from mask carriers had shown significant reduction after Adixen pod conditioning process. Focus had been made on optimized vacuum step (for AMC) after particles carrier cleaning cycle. Based upon these key results new procedures, as well as guidelines for mask carrier cleaning optimization are proposed to improve pod contamination control. Summary results/next steps: This paper reports molecular contamination measurement campaigns performed by a pool of European partners along the mask supply chain. It allows us to investigate, identify and quantify critical molecular contamination in mask pod, as well as VOC and humidity, issues depending on locations, uses, and carrier's type. Preliminary studies highlight initial process solutions for pods conditioning that are being used for short term industrialization and further industrialized.
Distributed road assessment system
Beer, N. Reginald; Paglieroni, David W
2014-03-25
A system that detects damage on or below the surface of a paved structure or pavement is provided. A distributed road assessment system includes road assessment pods and a road assessment server. Each road assessment pod includes a ground-penetrating radar antenna array and a detection system that detects road damage from the return signals as the vehicle on which the pod is mounted travels down a road. Each road assessment pod transmits to the road assessment server occurrence information describing each occurrence of road damage that is newly detected on a current scan of a road. The road assessment server maintains a road damage database of occurrence information describing the previously detected occurrences of road damage. After the road assessment server receives occurrence information for newly detected occurrences of road damage for a portion of a road, the road assessment server determines which newly detected occurrences correspond to which previously detected occurrences of road damage.
InstrumentationPod (IPOD) User Guide
DOE Office of Scientific and Technical Information (OSTI.GOV)
Parker, Robert F.
2014-06-12
This document describes the Instrumentation Pod (IPOD) and its operation and use. The IPOD is a low-power detector system comprising a 3He tube with preamp for neutron detection, a microcontroller-based data acquisition system, a GPS receiver for locationdetermination and time-synchronization, and power filtering and protection. The IPOD is intended to be bolted to the top of Dual-Use Casks stored at Baikal-1 in Kazakhstan in order to maintain continuity of knowledge of the materials stored within the cask. The data acquisition system receives pulses from the neutron-detection preamp, combines this information with other sensor data, and stores the result on twomore » SD cards that are part of the data acquisition system. Firmware in the data acquisition system controls collection and storing of the data and enables configuration of the acquisition parameters.« less
Metabolic changes in different developmental stages of Vanilla planifolia pods.
Palama, Tony Lionel; Khatib, Alfi; Choi, Young Hae; Payet, Bertrand; Fock, Isabelle; Verpoorte, Robert; Kodja, Hippolyte
2009-09-09
The metabolomic analysis of developing Vanilla planifolia green pods (between 3 and 8 months after pollination) was carried out by nuclear magnetic resonance (NMR) spectroscopy and multivariate data analysis. Multivariate data analysis of the (1)H NMR spectra, such as principal component analysis (PCA) and partial least-squares-discriminant analysis (PLS-DA), showed a trend of separation of those samples based on the metabolites present in the methanol/water (1:1) extract. Older pods had a higher content of glucovanillin, vanillin, p-hydroxybenzaldehyde glucoside, p-hydroxybenzaldehyde, and sucrose, while younger pods had more bis[4-(beta-D-glucopyranosyloxy)-benzyl]-2-isopropyltartrate (glucoside A), bis[4-(beta-D-glucopyranosyloxy)-benzyl]-2-(2-butyl)tartrate (glucoside B), glucose, malic acid, and homocitric acid. A liquid chromatography-mass spectrometry (LC-MS) analysis targeted at phenolic compound content was also performed on the developing pods and confirmed the NMR results. Ratios of aglycones/glucosides were estimated and thus allowed for detection of more minor metabolites in the green vanilla pods. Quantification of compounds based on both LC-MS and NMR analyses showed that free vanillin can reach 24% of the total vanillin content after 8 months of development in the vanilla green pods.
Low-dimensional and Data Fusion Techniques Applied to a Rectangular Supersonic Multi-stream Jet
NASA Astrophysics Data System (ADS)
Berry, Matthew; Stack, Cory; Magstadt, Andrew; Ali, Mohd; Gaitonde, Datta; Glauser, Mark
2017-11-01
Low-dimensional models of experimental and simulation data for a complex supersonic jet were fused to reconstruct time-dependent proper orthogonal decomposition (POD) coefficients. The jet consists of a multi-stream rectangular single expansion ramp nozzle, containing a core stream operating at Mj , 1 = 1.6 , and bypass stream at Mj , 3 = 1.0 with an underlying deck. POD was applied to schlieren and PIV data to acquire the spatial basis functions. These eigenfunctions were projected onto their corresponding time-dependent large eddy simulation (LES) fields to reconstruct the temporal POD coefficients. This reconstruction was able to resolve spectral peaks that were previously aliased due to the slower sampling rates of the experiments. Additionally, dynamic mode decomposition (DMD) was applied to the experimental and LES datasets, and the spatio-temporal characteristics were compared to POD. The authors would like to acknowledge AFOSR, program manager Dr. Doug Smith, for funding this research, Grant No. FA9550-15-1-0435.
Kostova-Vassilevska, Tanya; Oxberry, Geoffrey M.
2017-09-17
In this study, we consider two proper orthogonal decomposition (POD) methods for dimension reduction of dynamical systems. The first method (M1) uses only time snapshots of the solution, while the second method (M2) augments the snapshot set with time-derivative snapshots. The goal of the paper is to analyze and compare the approximation errors resulting from the two methods by using error bounds. We derive several new bounds of the error from POD model reduction by each of the two methods. The new error bounds involve a multiplicative factor depending on the time steps between the snapshots. For method M1 themore » factor depends on the second power of the time step, while for method 2 the dependence is on the fourth power of the time step, suggesting that method M2 can be more accurate for small between-snapshot intervals. However, three other factors also affect the size of the error bounds. These include (i) the norm of the second (for M1) and fourth derivatives (M2); (ii) the first neglected singular value and (iii) the spectral properties of the projection of the system’s Jacobian in the reduced space. Because of the interplay of these factors neither method is more accurate than the other in all cases. Finally, we present numerical examples demonstrating that when the number of collected snapshots is small and the first neglected singular value has a value of zero, method M2 results in a better approximation.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kostova-Vassilevska, Tanya; Oxberry, Geoffrey M.
In this study, we consider two proper orthogonal decomposition (POD) methods for dimension reduction of dynamical systems. The first method (M1) uses only time snapshots of the solution, while the second method (M2) augments the snapshot set with time-derivative snapshots. The goal of the paper is to analyze and compare the approximation errors resulting from the two methods by using error bounds. We derive several new bounds of the error from POD model reduction by each of the two methods. The new error bounds involve a multiplicative factor depending on the time steps between the snapshots. For method M1 themore » factor depends on the second power of the time step, while for method 2 the dependence is on the fourth power of the time step, suggesting that method M2 can be more accurate for small between-snapshot intervals. However, three other factors also affect the size of the error bounds. These include (i) the norm of the second (for M1) and fourth derivatives (M2); (ii) the first neglected singular value and (iii) the spectral properties of the projection of the system’s Jacobian in the reduced space. Because of the interplay of these factors neither method is more accurate than the other in all cases. Finally, we present numerical examples demonstrating that when the number of collected snapshots is small and the first neglected singular value has a value of zero, method M2 results in a better approximation.« less
Errors from approximation of ODE systems with reduced order models
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vassilevska, Tanya
2016-12-30
This is a code to calculate the error from approximation of systems of ordinary differential equations (ODEs) by using Proper Orthogonal Decomposition (POD) Reduced Order Models (ROM) methods and to compare and analyze the errors for two POD ROM variants. The first variant is the standard POD ROM, the second variant is a modification of the method using the values of the time derivatives (a.k.a. time-derivative snapshots). The code compares the errors from the two variants under different conditions.
Blood-Brain Barrier Disruption After Cardiopulmonary Bypass: Diagnosis and Correlation to Cognition.
Abrahamov, Dan; Levran, Oren; Naparstek, Sharon; Refaeli, Yael; Kaptson, Shani; Abu Salah, Mahmud; Ishai, Yaron; Sahar, Gideon
2017-07-01
Cardiopulmonary bypass (CPB) elicits a systemic inflammatory response that may impair blood-brain barrier (BBB) integrity. BBB disruption can currently be detected by dynamic contrast enhancement magnetic resonance imaging (MRI), reflected by an increase in the permeability constant (K trans ). We aimed to determine (1) whether CPB induces BBB disruption, (2) duration until BBB disruption resolution, and (3) the obtainable correlation between BBB injury (location and intensity) and neurocognitive dysfunction. Seven patients undergoing CPB with coronary artery bypass grafting (CABG) were assigned to serial cerebral designated MRI evaluations, preoperatively and on postoperative day (POD) 1 and 5. Examinations were analyzed for BBB disruption and microemboli using dynamic contrast enhancement MRI and diffusion-weighted imaging methods, respectively. Neuropsychologic tests were performed 1 day preoperatively and on POD 5. A significant local K trans increase (0.03 min -1 vs 0.07 min -1 , p = 0.033) compatible with BBB disruption was evident in 5 patients (71%) on POD 1. Resolution was observed by POD 5 (mean, 0.012 min -1 ). The location of the disruption was most prominent in the frontal lobes (400% vs 150% K trans levels upsurge, p = 0.05). MRI evidence of microembolization was demonstrated in only 1 patient (14%). The postoperative global cognitive score was reduced in all patients (98.2 ± 12 vs 95.1 ± 11, p = 0.032), predominantly in executive and attention (frontal lobe-related) functions (91.8 ± 13 vs 86.9 ± 12, p = 0.042). The intensity of the dynamic contrast enhancement MRI BBB impairment correlated with the magnitude of cognition reduction (r = 0.69, p = 0.04). BBB disruption was evident in most patients, primarily in the frontal lobes. The location and intensity of the BBB disruption, rather than the microembolic load, correlated with postoperative neurocognitive dysfunction. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.
A Wing Pod-based Millimeter Wave Cloud Radar on HIAPER
NASA Astrophysics Data System (ADS)
Vivekanandan, Jothiram; Tsai, Peisang; Ellis, Scott; Loew, Eric; Lee, Wen-Chau; Emmett, Joanthan
2014-05-01
One of the attractive features of a millimeter wave radar system is its ability to detect micron-sized particles that constitute clouds with lower than 0.1 g m-3 liquid or ice water content. Scanning or vertically-pointing ground-based millimeter wavelength radars are used to study stratocumulus (Vali et al. 1998; Kollias and Albrecht 2000) and fair-weather cumulus (Kollias et al. 2001). Airborne millimeter wavelength radars have been used for atmospheric remote sensing since the early 1990s (Pazmany et al. 1995). Airborne millimeter wavelength radar systems, such as the University of Wyoming King Air Cloud Radar (WCR) and the NASA ER-2 Cloud Radar System (CRS), have added mobility to observe clouds in remote regions and over oceans. Scientific requirements of millimeter wavelength radar are mainly driven by climate and cloud initiation studies. Survey results from the cloud radar user community indicated a common preference for a narrow beam W-band radar with polarimetric and Doppler capabilities for airborne remote sensing of clouds. For detecting small amounts of liquid and ice, it is desired to have -30 dBZ sensitivity at a 10 km range. Additional desired capabilities included a second wavelength and/or dual-Doppler winds. Modern radar technology offers various options (e.g., dual-polarization and dual-wavelength). Even though a basic fixed beam Doppler radar system with a sensitivity of -30 dBZ at 10 km is capable of satisfying cloud detection requirements, the above-mentioned additional options, namely dual-wavelength, and dual-polarization, significantly extend the measurement capabilities to further reduce any uncertainty in radar-based retrievals of cloud properties. This paper describes a novel, airborne pod-based millimeter wave radar, preliminary radar measurements and corresponding derived scientific products. Since some of the primary engineering requirements of this millimeter wave radar are that it should be deployable on an airborne platform, occupy minimum cabin space and maximize scan coverage, a pod-based configuration was adopted. Currently, the radar system is capable of collecting observations between zenith and nadir in a fixed scanning mode. Measurements are corrected for aircraft attitude changes. The near-nadir and zenith pointing observations minimize the cross-track Doppler contamination in the radial velocity measurements. An extensive engineering monitoring mechanism is built into the recording system status such as temperature, pressure, various electronic components' status and receiver characteristics. Status parameters are used for real-time system stability estimates and correcting radar system parameters. The pod based radar system is mounted on a modified Gulfstream V aircraft, which is operated and maintained by the National Center for Atmospheric Research (NCAR) on behalf of the National Science Foundation (NSF). The aircraft is called the High-Performance Instrumented Airborne Platform for Environmental Research (HIAPER) (Laursen et al., 2006). It is also instrumented with high spectral resolution lidar (HSRL) and an array of in situ and remote sensors for atmospheric research. As part of the instrument suite for HIAPER, the NSF funded the development of the HIAPER Cloud Radar (HCR). The HCR is an airborne, millimeter-wavelength, dual-polarization, Doppler radar that serves the atmospheric science community by providing cloud remote sensing capabilities for the NSF/NCAR G-V (HIAPER) aircraft. An optimal radar configuration that is capable of maximizing the accuracy of both qualitative and quantitative estimated cloud microphysical and dynamical properties is the most attractive option to the research community. The Technical specifications of cloud radar are optimized for realizing the desired scientific performance for the pod-based configuration. The radar was both ground and flight tested and preliminary measurements of Doppler and polarization measurements were collected. HCR observed sensitivity as low as -37 dBZ at 1 km range and resolved linear depolarization ratio (LDR) signature better than -29 dB during its latest test flights. References: Kollias, P., and B. A. Albrecht, 2000: The turbulence structure in a continental stratocumulus cloud from millimeter wavelength radar observation. J. Atmos. Sci., 57, 2417-2434. Kollias, P., B.A. Albrecht, R. Lhermitte, and A. Savtchenko, 2001: Radar observations of updrafts, downdrafts, and turbulence in fair weather cumuli. J. Atmos. Sci. 58, 1750-1766. Laursen, K. K., D. P. Jorgensen, G. P. Brasseur, S. L. Ustin, and J. Hunning, 2006: HIAPER: The next generation NSF/NCAR research aircraft. Bulletin of the American Meteorological Society, 87, 896-909. Pazmany, A. L., R. E. McIntosh, R. Kelly, and V. G., 1994: An airborne 95-GHz dual-polarized radar for cloud studies. IEEE Trans. Geosci. Remote Sens., 32, 731-739. Vali, G., Kelly, R.D., French, J., Haimov, S., Leon, D., McIntosh, R., Pazmany, A., 1998. Fine-scale structure and microphysics of coastal stratus. J. Atmos. Sci. 55, 3540-3564.
Johnson, Leslie N; Cashman, Siobhan M; Kumar-Singh, Rajendra
2008-01-01
As in other organ systems, gene and drug delivery to ocular tissues such as the retina and cornea is hampered by inefficient penetration of therapeutic molecules across the plasma membrane. We describe the use of a novel peptide for ocular delivery (POD) with protein transduction properties, for delivery of small and large molecules across the plasma membrane. POD enters cells within 5 minutes in a temperature dependent manner. POD can compact and deliver plasmid DNA, achieving transgene expression in >50% of human embryonic retinoblasts. Delivery of small interfering RNA (siRNA) duplexes to cells using POD, allowed for silencing of transgene expression by >50%. POD could also be used to deliver quantum dots in vitro and in vivo. Upon ocular delivery, POD rapidly entered neural retina and localized to retinal pigment epithelium (RPE), photoreceptor, and ganglion cells. Additionally, POD was able to enter corneal epithelium, sclera, choroid, and the dura of the optic nerve via topical application. POD also functions as a bacteriostatic, a useful property for a carrier of molecules to post mitotic neural ocular tissues.
Lan, Xiang; Zhang, Hua; Li, Hongyu; Chen, Kefei; Liu, Fei; Wei, Yonggang; Li, Bo
2018-05-31
We set out to acquire original pathophysiologic data of dynamic changes in portal vein pressure gradient (PVPG) following liver resection (LR) during post-operation days (POD) 1-7. Portal vein pressure gradient was measured in 31 patients daily until POD 7 at our liver surgery center. Patients were divided into non-, mild, moderate, and severe cirrhosis groups according to histopathology and were also divided into subgroups according to the volume of hepatectomy. Portal vein pressure gradient reached its peak on POD 3 in mild cirrhosis (F = 7.525, P < 0.001), moderate cirrhosis (F = 11.200, P < 0.001), and severe cirrhosis groups (F = 26.634, P < 0.001). There were no significant changes in PVPG in the non-cirrhosis group (F = 1.050, P = 0.411). Moreover, PVPG on POD 3 was higher with increasing severity of cirrhosis under the same interval of LR volume (resection volume <200 cm 3 : F = 13.040, P = 0.004; ≥200 cm 3 but <400 cm 3 : F = 13.243, P = 0.004; ≥400 cm 3 : F = 43.685, P < 0.001). Finally, the LR volume had significant impact on PVPG for patients with moderate cirrhosis (F = 6.339, P = 0.033) and severe cirrhosis (t = -7.000, P = 0.020). A similar tendency was also observed when patients were divided according to the ratio of the resected liver volume to total liver volume. The increase in PVPG following LR was positively associated with the degree of cirrhosis, significantly peaking on POD 3. The LR volume only had a significant impact on PVPG for patients with moderate and severe cirrhosis. This represents the first time, to our knowledge, that dynamic changes of PVPG after LR were measured and compared to cirrhosis and resection volume. © 2018 The Japan Society of Hepatology.
Open Source Dataturbine (OSDT) Android Sensorpod in Environmental Observing Systems
NASA Astrophysics Data System (ADS)
Fountain, T. R.; Shin, P.; Tilak, S.; Trinh, T.; Smith, J.; Kram, S.
2014-12-01
The OSDT Android SensorPod is a custom-designed mobile computing platform for assembling wireless sensor networks for environmental monitoring applications. Funded by an award from the Gordon and Betty Moore Foundation, the OSDT SensorPod represents a significant technological advance in the application of mobile and cloud computing technologies to near-real-time applications in environmental science, natural resources management, and disaster response and recovery. It provides a modular architecture based on open standards and open-source software that allows system developers to align their projects with industry best practices and technology trends, while avoiding commercial vendor lock-in to expensive proprietary software and hardware systems. The integration of mobile and cloud-computing infrastructure represents a disruptive technology in the field of environmental science, since basic assumptions about technology requirements are now open to revision, e.g., the roles of special purpose data loggers and dedicated site infrastructure. The OSDT Android SensorPod was designed with these considerations in mind, and the resulting system exhibits the following characteristics - it is flexible, efficient and robust. The system was developed and tested in the three science applications: 1) a fresh water limnology deployment in Wisconsin, 2) a near coastal marine science deployment at the UCSD Scripps Pier, and 3) a terrestrial ecological deployment in the mountains of Taiwan. As part of a public education and outreach effort, a Facebook page with daily ocean pH measurements from the UCSD Scripps pier was developed. Wireless sensor networks and the virtualization of data and network services is the future of environmental science infrastructure. The OSDT Android SensorPod was designed and developed to harness these new technology developments for environmental monitoring applications.
Replacement of Atlantis', OV-104's, right orbital maneuvering system pod
NASA Technical Reports Server (NTRS)
1988-01-01
Atlantis', Orbiter Vehicle (OV) 104's, right orbital maneuvering system (OMS) pod (RP01) is placed in a checkout cell at Kennedy Space Center's (KSC's) Hypergolic Maintenance Facility (HMF). Technicians steady OMS mounted on ground handling cart as third technician, standing on ladder, secures support frame. At the HMF, a group of specially-equipped buildings in the KSC Industrial Area, the OMS pods are undergoing extensive processing, including removal of certain components that will undergo modification at vendor facilities prior to the Shuttle's return to flight. The OMS pods are bolted to the aft fuselage of the orbiter and contain the engines and thrusters used to maneuver the spaceship in orbit. View provided by KSC with alternate number KSC-87PC-93.
Evaluation results of a new EUV reticle pod based on SEMI E152
NASA Astrophysics Data System (ADS)
Ota, Kazuya; Yonekawa, Masami; Taguchi, Takao; Suga, Osamu
2010-04-01
To protect the reticle during shipping, storage and tool handling, various reticle pod concepts have been proposed and evaluated in the last 10 years. MIRAI-Selete has been developing EUV reticle handling technology and evaluating EUV reticle pods designed using "Dual Pod Concept" for four years. The concept was jointly proposed by Canon and Nikon at the EUV mask technology and standards workshop at Miyazaki in November 2004; a mask is doubly protected by an inner pod and an outer pod and the mask is carried into an exposure tool with the inner pod. Canon, Nikon and Entegris have started collaboration in 2005 and developed three types of EUV pod prototypes, alpha, beta and gamma. The gamma pods were evaluated by MIRAI-Selete and the superiority of the dual pod concept has been verified with many experimental data on shipping, storage and tool handling. The dual pod concept was standardized as SEMI E152-0709 "Mechanical Specification of EUV Pods for 150mm EUVL Reticles" in 2009. Canon, Nikon and Entegris have developed a new pod design compatible with SEMI E152; it has a Type A inner baseplate for uses with EUV exposure tools. The baseplate has two alignment windows, a window for a data matrix symbol and five pockets as the front edge grip exclusion volumes. In addition to the new features, there are some differences between the new SEMI compliant pod design and the former design "CNE-gamma", e.g. the material of the inner cover was changed to metal to reduce outgassing rate and the gap between the reticle and the side supports were widened to satisfy a requirement of the standard. MIRAI-Selete has evaluated the particle protective capability of the new SEMI compliant pods "cnPod" during shipping, storage and tool handling in vacuum and found the "cnPod" has the excellent particle protective capability and the dual pod concept can be used not only for EUVL pilot line but also for EUVL high volume manufacturing.
Boeing 747 aircraft with large external pod for transporting outsize cargo
NASA Technical Reports Server (NTRS)
Price, J. E.; Quartero, C. B.; Smith, P. M.; Washburn, G. F.
1979-01-01
The effect on structural arrangement, system weight, and range performance of the cargo pod payload carrying capability was determined to include either the bridge launcher or a spacelab module on a Boeing 747 aircraft. Modifications to the carrier aircraft and the installation time required to attach the external pod to the 747 were minimized. Results indicate that the increase in pod size was minimal, and that the basic 747 structure was adequate to safely absorb the load induced by ground or air operation while transporting either payload.
TreePOD: Sensitivity-Aware Selection of Pareto-Optimal Decision Trees.
Muhlbacher, Thomas; Linhardt, Lorenz; Moller, Torsten; Piringer, Harald
2018-01-01
Balancing accuracy gains with other objectives such as interpretability is a key challenge when building decision trees. However, this process is difficult to automate because it involves know-how about the domain as well as the purpose of the model. This paper presents TreePOD, a new approach for sensitivity-aware model selection along trade-offs. TreePOD is based on exploring a large set of candidate trees generated by sampling the parameters of tree construction algorithms. Based on this set, visualizations of quantitative and qualitative tree aspects provide a comprehensive overview of possible tree characteristics. Along trade-offs between two objectives, TreePOD provides efficient selection guidance by focusing on Pareto-optimal tree candidates. TreePOD also conveys the sensitivities of tree characteristics on variations of selected parameters by extending the tree generation process with a full-factorial sampling. We demonstrate how TreePOD supports a variety of tasks involved in decision tree selection and describe its integration in a holistic workflow for building and selecting decision trees. For evaluation, we illustrate a case study for predicting critical power grid states, and we report qualitative feedback from domain experts in the energy sector. This feedback suggests that TreePOD enables users with and without statistical background a confident and efficient identification of suitable decision trees.
2007-01-23
KENNEDY SPACE CENTER, FLA. -- The right-hand orbital maneuvering system pod is being delivered to Orbiter Processing Facility bay 2 for installation on the orbiter Endeavour. The orbital maneuvering system/reaction control system left- and right-hand pods are attached to the upper aft fuselage left and right sides. Each pod is fabricated primarily of graphite epoxy composite and aluminum. Each pod is 21.8 feet long and 11.37 feet wide at its aft end and 8.41 feet wide at its forward end, with a surface area of approximately 435 square feet. The orbiter is being prepared for its first launch in just over four years. The vehicle has undergone an extensive modification period, including the addition of all of the return-to-flight safety upgrades added to both Discovery and Atlantis. Endeavour is targeted for launch of mission STS-118 on June 28. Photo credit: NASA/Kim Shiflett
2007-01-23
KENNEDY SPACE CENTER, FLA. -- The right-hand orbital maneuvering system pod is driven past the Vehicle Assembly Building on its way to Orbiter Processing Facility bay 2 for installation on the orbiter Endeavour. The orbital maneuvering system/reaction control system left- and right-hand pods are attached to the upper aft fuselage left and right sides. Each pod is fabricated primarily of graphite epoxy composite and aluminum. Each pod is 21.8 feet long and 11.37 feet wide at its aft end and 8.41 feet wide at its forward end, with a surface area of approximately 435 square feet. The orbiter is being prepared for its first launch in just over four years. The vehicle has undergone an extensive modification period, including the addition of all of the return-to-flight safety upgrades added to both Discovery and Atlantis. Endeavour is targeted for launch of mission STS-118 on June 28. Photo credit: NASA/Kim Shiflett
Application of low-dimensional techniques for closed-loop control of turbulent flows
NASA Astrophysics Data System (ADS)
Ausseur, Julie
The groundwork for an advanced closed-loop control of separated shear layer flows is laid out in this document. The experimental testbed for the present investigation is the turbulent flow over a NACA-4412 model airfoil tested in the Syracuse University subsonic wind tunnel at Re=135,000. The specified control objective is to delay separation - or stall - by constantly keeping the flow attached to the surface of the wing. The proper orthogonal decomposition (POD) is shown to he a valuable tool to provide a low-dimensional estimate of the flow state and the first POD expansion coefficient is proposed to he used as the control variable. Other reduced-order techniques such as the modified linear and quadratic stochastic measurement methods (mLSM, mQSM) are applied to reduce the complexity of the flow field and their ability to accurately estimate the flow state from surface pressure measurements alone is examined. A simple proportional feedback control is successfully implemented in real-time using these tools and flow separation is efficiently delayed by over 3 degrees angle of attack. To further improve the quality of the flow state estimate, the implementation of a Kalman filter is foreseen, in which the knowledge of the flow dynamics is added to the computation of the control variable to correct for the potential measurement errors. To this aim, a reduced-order model (ROM) of the flow is developed using the least-squares method to obtain the coefficients of the POD/Galerkin projection of the Navier-Stokes equations from experimental data. To build the training ensemble needed in this experimental procedure, the spectral mLSM is performed to generate time-resolved series of POD expansion coefficients from which temporal derivatives are computed. This technique, which is applied to independent PIV velocity snapshots and time-resolved surface measurements, is able to retrieve the rational temporal evolution of the flow physics in the entire 2-D measurement area. The quality of the spectral measurements is confirmed by the results from both the linear and quadratic dynamical systems. The preliminary results from the linear ROM strengthens the motivation for future control implementation of a linear Kalman filter in this flow.
Performance Evaluation of the United Nations Environment ...
A request for technical collaboration between the UNEP and the US EPA resulted in the establishment of a MCRADA. The purpose of this agreement was to evaluate an air quality monitoring system (referred to as the UNEP pod) developed by the UNEP for use in environmental situations where more sophisticated monitoring instrumentation was not available. The US EPA has conducted numerous evaluations of other similar sensor pods at its Research Triangle Park, NC research campus and has trained staff as well as established research designs for such efforts. Under the terms of the MCRADA, the US EPA would operate the pod using UNEP provided operating procedures in a manner consistent with its planned intent of deployment. The US EPA would collect air quality monitoring data from the pod involving select environmental measures over a period of approximately one month. Reference monitoring data collected from collocated federal regulatory monitors would be used to establish a comparison between the two systems and thus establishment of performance characteristics. In addition, the US EPA would provide feedback information to the UNEP as to observed ease of use features of the pod that would be beneficial in its future evolution and deployment. The UNEP recently developed a multipollutant sensor pod called the UNEP Air Quality Monitoring Unit, herein simply defined as the UNEP pod (http://aqicn.org/faq/2015-10-28/unep-air-quality-monitoring-station/). First introduced in 20
On a framework for generating PoD curves assisted by numerical simulations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Subair, S. Mohamed, E-mail: prajagopal@iitm.ac.in; Agrawal, Shweta, E-mail: prajagopal@iitm.ac.in; Balasubramaniam, Krishnan, E-mail: prajagopal@iitm.ac.in
2015-03-31
The Probability of Detection (PoD) curve method has emerged as an important tool for the assessment of the performance of NDE techniques, a topic of particular interest to the nuclear industry where inspection qualification is very important. The conventional experimental means of generating PoD curves though, can be expensive, requiring large data sets (covering defects and test conditions), and equipment and operator time. Several methods of achieving faster estimates for PoD curves using physics-based modelling have been developed to address this problem. Numerical modelling techniques are also attractive, especially given the ever-increasing computational power available to scientists today. Here wemore » develop procedures for obtaining PoD curves, assisted by numerical simulation and based on Bayesian statistics. Numerical simulations are performed using Finite Element analysis for factors that are assumed to be independent, random and normally distributed. PoD curves so generated are compared with experiments on austenitic stainless steel (SS) plates with artificially created notches. We examine issues affecting the PoD curve generation process including codes, standards, distribution of defect parameters and the choice of the noise threshold. We also study the assumption of normal distribution for signal response parameters and consider strategies for dealing with data that may be more complex or sparse to justify this. These topics are addressed and illustrated through the example case of generation of PoD curves for pulse-echo ultrasonic inspection of vertical surface-breaking cracks in SS plates.« less
On a framework for generating PoD curves assisted by numerical simulations
NASA Astrophysics Data System (ADS)
Subair, S. Mohamed; Agrawal, Shweta; Balasubramaniam, Krishnan; Rajagopal, Prabhu; Kumar, Anish; Rao, Purnachandra B.; Tamanna, Jayakumar
2015-03-01
The Probability of Detection (PoD) curve method has emerged as an important tool for the assessment of the performance of NDE techniques, a topic of particular interest to the nuclear industry where inspection qualification is very important. The conventional experimental means of generating PoD curves though, can be expensive, requiring large data sets (covering defects and test conditions), and equipment and operator time. Several methods of achieving faster estimates for PoD curves using physics-based modelling have been developed to address this problem. Numerical modelling techniques are also attractive, especially given the ever-increasing computational power available to scientists today. Here we develop procedures for obtaining PoD curves, assisted by numerical simulation and based on Bayesian statistics. Numerical simulations are performed using Finite Element analysis for factors that are assumed to be independent, random and normally distributed. PoD curves so generated are compared with experiments on austenitic stainless steel (SS) plates with artificially created notches. We examine issues affecting the PoD curve generation process including codes, standards, distribution of defect parameters and the choice of the noise threshold. We also study the assumption of normal distribution for signal response parameters and consider strategies for dealing with data that may be more complex or sparse to justify this. These topics are addressed and illustrated through the example case of generation of PoD curves for pulse-echo ultrasonic inspection of vertical surface-breaking cracks in SS plates.
NASA Technical Reports Server (NTRS)
Generazio, Edward R.
2014-01-01
Unknown risks are introduced into failure critical systems when probability of detection (POD) capabilities are accepted without a complete understanding of the statistical method applied and the interpretation of the statistical results. The presence of this risk in the nondestructive evaluation (NDE) community is revealed in common statements about POD. These statements are often interpreted in a variety of ways and therefore, the very existence of the statements identifies the need for a more comprehensive understanding of POD methodologies. Statistical methodologies have data requirements to be met, procedures to be followed, and requirements for validation or demonstration of adequacy of the POD estimates. Risks are further enhanced due to the wide range of statistical methodologies used for determining the POD capability. Receiver/Relative Operating Characteristics (ROC) Display, simple binomial, logistic regression, and Bayes' rule POD methodologies are widely used in determining POD capability. This work focuses on Hit-Miss data to reveal the framework of the interrelationships between Receiver/Relative Operating Characteristics Display, simple binomial, logistic regression, and Bayes' Rule methodologies as they are applied to POD. Knowledge of these interrelationships leads to an intuitive and global understanding of the statistical data, procedural and validation requirements for establishing credible POD estimates.
Grangeon, Romain; Zupan, John R.; Anderson-Furgeson, James; Zambryski, Patricia C.
2015-01-01
Agrobacterium tumefaciens elongates by addition of peptidoglycan (PG) only at the pole created by cell division, the growth pole, whereas the opposite pole, the old pole, is inactive for PG synthesis. How Agrobacterium assigns and maintains pole asymmetry is not understood. Here, we investigated whether polar growth is correlated with novel pole-specific localization of proteins implicated in a variety of growth and cell division pathways. The cell cycle of A. tumefaciens was monitored by time-lapse and superresolution microscopy to image the localization of A. tumefaciens homologs of proteins involved in cell division, PG synthesis and pole identity. FtsZ and FtsA accumulate at the growth pole during elongation, and improved imaging reveals FtsZ disappears from the growth pole and accumulates at the midcell before FtsA. The L,D-transpeptidase Atu0845 was detected mainly at the growth pole. A. tumefaciens specific pole-organizing protein (Pop) PopZAt and polar organelle development (Pod) protein PodJAt exhibited dynamic yet distinct behavior. PopZAt was found exclusively at the growing pole and quickly switches to the new growth poles of both siblings immediately after septation. PodJAt is initially at the old pole but then also accumulates at the growth pole as the cell cycle progresses suggesting that PodJAt may mediate the transition of the growth pole to an old pole. Thus, PopZAt is a marker for growth pole identity, whereas PodJAt identifies the old pole. PMID:26324921
Alleviation of podophyllotoxin toxicity using coexisting flavonoids from Dysosma versipellis.
Li, Juan; Sun, Hua; Jin, Lu; Cao, Wei; Zhang, Jin; Guo, Chong-Yi; Ding, Ke; Luo, Cheng; Ye, Wen-Cai; Jiang, Ren-Wang
2013-01-01
Podophyllotoxin (POD) is a lignan-type toxin existing in many herbs used in folk medicine. Until now, no effective strategy is available for the management of POD intoxication. This study aims to determine the protective effects of flavonoids (quercetin and kaempferol) on POD-induced toxicity. In Vero cells, both flavonoids protected POD-induced cytotoxicity by recovering alleviating G2/M arrest, decreasing ROS generation and changes of membrane potential, and recovering microtubule structure. In Swiss mice, the group given both POD and flavonoids group had significantly lower mortality rate and showed less damages in the liver and kidney than the group given POD alone. As compared to the POD group, the POD plus flavonoids group exhibited decreases in plasma transaminases, alkaline phosphatase, lactate dehydrogenase, plasma urea, creatinine and malondialdehyde levels, and increases in superoxide dismutase and glutathione levels. Histological examination of the liver and kidney showed less pathological changes in the treatment of POD plus flavonoids group. The protective mechanisms were due to the antioxidant activity of flavonoids against the oxidative stress induced by POD and the competitive binding of flavonoids against POD for the same colchicines-binding sites. The latter binding was confirmed by the tubulin assembly assay in combination with molecular docking analyses. In conclusion, this study for the first time demonstrated that the coexisting flavonoids have great protective effects against the POD toxicity, and results of this study highlighted the great potential of searching for effective antidotes against toxins based on the pharmacological clues.
Xu, Pei; Wu, Xinyi; Muñoz-Amatriaín, María; Wang, Baogen; Wu, Xiaohua; Hu, Yaowen; Huynh, Bao-Lam; Close, Timothy J; Roberts, Philip A; Zhou, Wen; Lu, Zhongfu; Li, Guojing
2017-05-01
Cowpea (V. unguiculata L. Walp) is a climate resilient legume crop important for food security. Cultivated cowpea (V. unguiculata L) generally comprises the bushy, short-podded grain cowpea dominant in Africa and the climbing, long-podded vegetable cowpea popular in Asia. How selection has contributed to the diversification of the two types of cowpea remains largely unknown. In the current study, a novel genotyping assay for over 50 000 SNPs was employed to delineate genomic regions governing pod length. Major, minor and epistatic QTLs were identified through QTL mapping. Seventy-two SNPs associated with pod length were detected by genome-wide association studies (GWAS). Population stratification analysis revealed subdivision among a cowpea germplasm collection consisting of 299 accessions, which is consistent with pod length groups. Genomic scan for selective signals suggested that domestication of vegetable cowpea was accompanied by selection of multiple traits including pod length, while the further improvement process was featured by selection of pod length primarily. Pod growth kinetics assay demonstrated that more durable cell proliferation rather than cell elongation or enlargement was the main reason for longer pods. Transcriptomic analysis suggested the involvement of sugar, gibberellin and nutritional signalling in regulation of pod length. This study establishes the basis for map-based cloning of pod length genes in cowpea and for marker-assisted selection of this trait in breeding programmes. © 2016 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.
Alleviation of Podophyllotoxin Toxicity Using Coexisting Flavonoids from Dysosma versipellis
Li, Juan; Sun, Hua; Jin, Lu; Cao, Wei; Zhang, Jin; Guo, Chong-Yi; Ding, Ke; Luo, Cheng; Ye, Wen-Cai; Jiang, Ren-Wang
2013-01-01
Podophyllotoxin (POD) is a lignan-type toxin existing in many herbs used in folk medicine. Until now, no effective strategy is available for the management of POD intoxication. This study aims to determine the protective effects of flavonoids (quercetin and kaempferol) on POD-induced toxicity. In Vero cells, both flavonoids protected POD-induced cytotoxicity by recovering alleviating G2/M arrest, decreasing ROS generation and changes of membrane potential, and recovering microtubule structure. In Swiss mice, the group given both POD and flavonoids group had significantly lower mortality rate and showed less damages in the liver and kidney than the group given POD alone. As compared to the POD group, the POD plus flavonoids group exhibited decreases in plasma transaminases, alkaline phosphatase, lactate dehydrogenase, plasma urea, creatinine and malondialdehyde levels, and increases in superoxide dismutase and glutathione levels. Histological examination of the liver and kidney showed less pathological changes in the treatment of POD plus flavonoids group. The protective mechanisms were due to the antioxidant activity of flavonoids against the oxidative stress induced by POD and the competitive binding of flavonoids against POD for the same colchicines-binding sites. The latter binding was confirmed by the tubulin assembly assay in combination with molecular docking analyses. In conclusion, this study for the first time demonstrated that the coexisting flavonoids have great protective effects against the POD toxicity, and results of this study highlighted the great potential of searching for effective antidotes against toxins based on the pharmacological clues. PMID:23991049
Teaching Adults with Moderate Intellectual Disability ATM Use via the "iPod"
ERIC Educational Resources Information Center
Scott, Renee; Collins, Belva; Knight, Victoria; Kleinert, Harold
2013-01-01
Money management can increase independence and access to communities for individuals with disabilities. Although research on computer-based instruction for teaching banking skills to students with intellectual disability is established, the use of portable electronic devices (e.g., iPod) has not been evaluated. iPods may be an effective, portable,…
Survey view of damage to the STS-117 OMS Pod taken by an Expedition 15 Crewmember
2007-06-13
ISS015E11804 (13 June 2007) --- A digital still camera recorded this image of a gap caused by an uplifted area on the thermal blanket protecting Atlantis' portside orbital maneuvering system (OMS) pod. The STS-117 Mission Management Team (MMT) has decided the best course of action to take in regard to the uplifted thermal blanket on the post side Orbital Maneuvering System Pod was to add the repair task on EVA 3 with astronauts Jim Reilly and John (Danny) Olivas.
2003-09-18
NASA Dryden's Automated Aerial Refueling (AAR) project evaluated the capability of an F/A-18A aircraft as an in-flight refueling tanker with the objective of developing analytical models for an automated aerial refueling system for unmanned air vehicles. The F/A-18 "tanker" aircraft (No. 847) underwent flight test envelope expansion with an aerodynamic pod containing air-refueling equipment carried beneath the fuselage. The second aircraft flew as the receiver aircraft during the study to assess the free-stream hose and drogue dynamics on the F/A-18A.
2003-09-18
NASA Dryden's Automated Aerial Refueling (AAR) project evaluated the capability of an F/A-18A aircraft as an in-flight refueling tanker with the objective of developing analytical models for an automated aerial refueling system for unmanned air vehicles. The F/A-18 "tanker" aircraft (No. 847) underwent flight test envelope expansion with an aerodynamic pod containing air-refueling equipment carried beneath the fuselage. The second aircraft flew as the receiver aircraft during the study to assess the free-stream hose and drogue dynamics on the F/A-18A.
2003-09-18
NASA Dryden's Automated Aerial Refueling (AAR) project evaluated the capability of an F/A-18A aircraft as an in-flight refueling tanker with the objective of developing analytical models for an automated aerial refueling system for unmanned air vehicles. The F/A-18 "tanker" aircraft (No. 847) underwent flight test envelope expansion with an aerodynamic pod containing air-refueling equipment carried beneath the fuselage. The second aircraft flew as the receiver aircraft during the study to assess the free-stream hose and drogue dynamics on the F/A-18A.
Koopman Mode Decomposition Methods in Dynamic Stall: Reduced Order Modeling and Control
2015-11-10
the flow phenomena by separating them into individual modes. The technique of Proper Orthogonal Decomposition (POD), see [ Holmes : 1998] is a popular...sampled values h(k), k = 0,…,2M-1, of the exponential sum 1. Solve the following linear system where 2. Compute all zeros zj D, j = 1,…,M...of the Prony polynomial i.e., calculate all eigenvalues of the associated companion matrix and form fj = log zj for j = 1,…,M, where log is the
NASA Technical Reports Server (NTRS)
Brink, Jeffrey S.
2005-01-01
The space shuttle Aft Propulsion System (APS) pod requires precision alignment to be installed onto the orbiter deck. The Ground Support Equipment (GSE) used to perform this task cannot be manipulated along a single Cartesian axis without causing motion along the other Cartesian axes. As a result, manipulations required to achieve a desired motion are not intuitive. My study calculated the joint angles required to align the APS pod, using reverse kinematic analysis techniques. Knowledge of these joint angles will allow the ground support team to align the APS pod more safely and efficiently. An uncertainty analysis was also performed to estimate the accuracy associated with this approach and to determine whether any inexpensive modifications can be made to further improve accuracy.
Probability of detection of defects in coatings with electronic shearography
NASA Astrophysics Data System (ADS)
Maddux, Gary A.; Horton, Charles M.; Lansing, Matthew D.; Gnacek, William J.; Newton, Patrick L.
1994-07-01
The goal of this research was to utilize statistical methods to evaluate the probability of detection (POD) of defects in coatings using electronic shearography. The coating system utilized in the POD studies was to be the paint system currently utilized on the external casings of the NASA Space Transportation System (STS) Revised Solid Rocket Motor (RSRM) boosters. The population of samples was to be large enough to determine the minimum defect size for 90 percent probability of detection of 95 percent confidence POD on these coatings. Also, the best methods to excite coatings on aerospace components to induce deformations for measurement by electronic shearography were to be determined.
Probability of detection of defects in coatings with electronic shearography
NASA Technical Reports Server (NTRS)
Maddux, Gary A.; Horton, Charles M.; Lansing, Matthew D.; Gnacek, William J.; Newton, Patrick L.
1994-01-01
The goal of this research was to utilize statistical methods to evaluate the probability of detection (POD) of defects in coatings using electronic shearography. The coating system utilized in the POD studies was to be the paint system currently utilized on the external casings of the NASA Space Transportation System (STS) Revised Solid Rocket Motor (RSRM) boosters. The population of samples was to be large enough to determine the minimum defect size for 90 percent probability of detection of 95 percent confidence POD on these coatings. Also, the best methods to excite coatings on aerospace components to induce deformations for measurement by electronic shearography were to be determined.
Pervasive Monitoring—An Intelligent Sensor Pod Approach for Standardised Measurement Infrastructures
Resch, Bernd; Mittlboeck, Manfred; Lippautz, Michael
2010-01-01
Geo-sensor networks have traditionally been built up in closed monolithic systems, thus limiting trans-domain usage of real-time measurements. This paper presents the technical infrastructure of a standardised embedded sensing device, which has been developed in the course of the Live Geography approach. The sensor pod implements data provision standards of the Sensor Web Enablement initiative, including an event-based alerting mechanism and location-aware Complex Event Processing functionality for detection of threshold transgression and quality assurance. The goal of this research is that the resultant highly flexible sensing architecture will bring sensor network applications one step further towards the realisation of the vision of a “digital skin for planet earth”. The developed infrastructure can potentially have far-reaching impacts on sensor-based monitoring systems through the deployment of ubiquitous and fine-grained sensor networks. This in turn allows for the straight-forward use of live sensor data in existing spatial decision support systems to enable better-informed decision-making. PMID:22163537
Resch, Bernd; Mittlboeck, Manfred; Lippautz, Michael
2010-01-01
Geo-sensor networks have traditionally been built up in closed monolithic systems, thus limiting trans-domain usage of real-time measurements. This paper presents the technical infrastructure of a standardised embedded sensing device, which has been developed in the course of the Live Geography approach. The sensor pod implements data provision standards of the Sensor Web Enablement initiative, including an event-based alerting mechanism and location-aware Complex Event Processing functionality for detection of threshold transgression and quality assurance. The goal of this research is that the resultant highly flexible sensing architecture will bring sensor network applications one step further towards the realisation of the vision of a "digital skin for planet earth". The developed infrastructure can potentially have far-reaching impacts on sensor-based monitoring systems through the deployment of ubiquitous and fine-grained sensor networks. This in turn allows for the straight-forward use of live sensor data in existing spatial decision support systems to enable better-informed decision-making.
Skowyra, Monika; Janiewicz, Urszula; Salejda, Anna Marietta; Krasnowska, Grażyna
2015-01-01
Summary The effect of dried pods of Caesalpinia spinosa, known as tara, on pH, cooking loss, lipid oxidation, colour stability and texture of model meat systems stored at 4 °C for 21 days was investigated. Tara pod powder showing a potential antioxidant activity was added at 0.02, 0.04 and 0.08% (by mass) directly to the pork batter and compared with a synthetic antioxidant, butylated hydroxyanisole (BHA) and control (no added antioxidants). The addition of tara pod powder at 0.02% was as effective as BHA (0.02%) in retarding lipid oxidation in pork products during storage. Results showed that redness increased after the addition of tara pod powder. Specifically, 0.02% of tara pod powder was effective in keeping the red colour of meat batter stored under illumination at 4 °C for 48 h. Hardness of pork products was the lowest in samples manufactured with tara pod powder compared with control. Results highlight the potential of using tara pod powder as natural functional ingredient in the development of pork products with enhanced quality and shelf life. PMID:27904376
FOCU:S--future operator control unit: soldier
NASA Astrophysics Data System (ADS)
O'Brien, Barry J.; Karan, Cem; Young, Stuart H.
2009-05-01
The U.S. Army Research Laboratory's (ARL) Computational and Information Sciences Directorate (CISD) has long been involved in autonomous asset control, specifically as it relates to small robots. Over the past year, CISD has been making strides in the implementation of three areas of small robot autonomy, namely platform autonomy, Soldier-robot interface, and tactical behaviors. It is CISD's belief that these three areas must be considered as a whole in order to provide Soldiers with useful capabilities. In addressing the Soldier-robot interface aspect, CISD has begun development on a unique dismounted controller called the Future Operator Control Unit: Soldier (FOCU:S) that is based on an Apple iPod Touch. The iPod Touch's small form factor, unique touch-screen input device, and the presence of general purpose computing applications such as a web browser combine to give this device the potential to be a disruptive technology. Setting CISD's implementation apart from other similar iPod or iPhone-based devices is the ARL software that allows multiple robotic platforms to be controlled from a single OCU. The FOCU:S uses the same Agile Computing Infrastructure (ACI) that all other assets in the ARL robotic control system use, enabling automated asset discovery on any type of network. Further, a custom ad hoc routing implementation allows the FOCU:S to communicate with the ARL ad hoc communications system and enables it to extend the range of the network. This paper will briefly describe the current robotic control architecture employed by ARL and provide short descriptions of existing capabilities. Further, the paper will discuss FOCU:S specific software developed for the iPod Touch, including unique capabilities enabled by the device's unique hardware.
Reduced-order model for underwater target identification using proper orthogonal decomposition
NASA Astrophysics Data System (ADS)
Ramesh, Sai Sudha; Lim, Kian Meng
2017-03-01
Research on underwater acoustics has seen major development over the past decade due to its widespread applications in domains such as underwater communication/navigation (SONAR), seismic exploration and oceanography. In particular, acoustic signatures from partially or fully buried targets can be used in the identification of buried mines for mine counter measures (MCM). Although there exist several techniques to identify target properties based on SONAR images and acoustic signatures, these methods first employ a feature extraction method to represent the dominant characteristics of a data set, followed by the use of an appropriate classifier based on neural networks or the relevance vector machine. The aim of the present study is to demonstrate the applications of proper orthogonal decomposition (POD) technique in capturing dominant features of a set of scattered pressure signals, and subsequent use of the POD modes and coefficients in the identification of partially buried underwater target parameters such as its location, size and material density. Several numerical examples are presented to demonstrate the performance of the system identification method based on POD. Although the present study is based on 2D acoustic model, the method can be easily extended to 3D models and thereby enables cost-effective representations of large-scale data.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-11-19
.... APHIS-2012-0042] RIN 0579-AD69 Importation of Fresh Beans, Shelled or in Pods, From Jordan Into the... shipments of fresh beans, shelled or in pods (French, green, snap, and string), from Jordan into the continental United States. As a condition of entry, the beans must be produced in accordance with a systems...
Copernicus POD Service: Orbit Determination of the Sentinel Satellites
NASA Astrophysics Data System (ADS)
Peter, Heike; Fernández, Jaime; Ayuga, Francisco; Féménias, Pierre
2016-04-01
The Copernicus POD (Precise Orbit Determination) Service is part of the Copernicus Processing Data Ground Segment (PDGS) of the Sentinel-1, -2 and -3 missions. A GMV-led consortium is operating the Copernicus POD Service being in charge of generating precise orbital products and auxiliary data files for their use as part of the processing chains of the respective Sentinel PDGS. Sentinel-1A was launched in April 2014 while Sentinel-2A was on June 2015 and both are routinely operated since then. Sentinel-3A is expected to be launched in February 2016 and Sentinel-1B is planned for spring 2016. Thus the CPOD Service will be operating three to four satellites simultaneously in spring 2016. The satellites of the Sentinel-1, -2, and -3 missions are all equipped with dual frequency high precision GPS receivers delivering the main observables for POD. Sentinel-3 satellites will additionally be equipped with a laser retro reflector for Satellite Laser Ranging and a receiver for DORIS tracking. All three types of observables (GPS, SLR and DORIS) will be used routinely for POD. The POD core of the CPOD Service is NAPEOS (Navigation Package for Earth Orbiting Satellites) the leading ESA/ESOC software for precise orbit determination. The careful selection of models and inputs is important to achieve the different but very demanding requirements in terms of orbital accuracy and timeliness for the Sentinel -1, -2 & -3 missions. The three missions require orbital products with various latencies from 30 minutes up to 20-30 days. The accuracy requirements are also different and partly very challenging, targeting 5 cm in 3D for Sentinel-1 and 2-3 cm in radial direction for Sentinel-3. Although the characteristics and the requirements are different for the three missions the same core POD setup is used to the largest extent possible. This strategy facilitates maintenance of the complex system of the CPOD Service. Updates in the dynamical modelling of the satellite orbits, e.g. improvements of the box-wing models, have been done to deliver best possible orbit solutions for the satellite. Quality control of the CPOD orbits is done by validating them with independent orbit solutions provided by the Copernicus POD Quality Working Group. The cross-comparison of orbit solutions from different institutions is essential to monitor and to improve the orbit accuracy because for Sentinel-1 and -2 this is the only possibility to externally assess the quality of the orbits. Sentinel-3 orbits may additionally be validated by using SLR and DORIS observations. This paper presents the Copernicus POD Service in terms of operations and orbital accuracy achieved by the different orbit products of the different missions. For Sentinel-1 and Sentinel-2, this paper presents the impact of the box-wing models. For Sentinel-3, the orbital accuracy will be assessed using the very first data after launch.
POD- Mapping and analysis of hydroturbine exit flow dynamics
NASA Astrophysics Data System (ADS)
Kjeldsen, Morten; Finstad, Pal Henrik
2012-11-01
Pairwise radial dynamic measurements of the swirling draft tube flow have been made at the 25 MW Svorka power plant in Surnadal operating at 48% load at 6 radial and 7 angular positions. The data is analyzed with traditional methods as well as with POD. The measurements were made in the turbine draft tube/exit flow in an axial measurement plane about 1200mm downstream the turbine runner. The draft tube diameter in the measurement plane is about 1300mm. The flow rate during measurements was close to 5.8m3/s. Two probes were used; both of length Le=700 mm and made of stainless steel with an outer diameter of Do=20 mm and inner diameter Di=4mm. At the end of each probe a full bridge cylindrical KULITE xcl152, 0-3.5, was mounted. 90 seconds samples at 10 kS/s were taken. The POD analysis largely follows that of Tutkun et al. (see e.g. AIAA J., 45,5,2008). The analysis shows that 26% of the pressure pulsation energy can be addressed to azimuthal mode 1. The work has been supported by Energy Norway.
NASA Astrophysics Data System (ADS)
Mao, X.; Visser, P. N. A. M.; van den IJssel, J.
2017-06-01
Precision Orbit Determination (POD) is a prerequisite for the success of many Low Earth Orbiting (LEO) satellite missions. With high-quality, dual-frequency Global Positioning System (GPS) receivers, typically precisions of the order of a few cm are possible for single-satellite POD, and of a few mm for relative POD of formation flying spacecraft with baselines up to hundreds of km. To achieve the best precision, the use of Phase Center Variation (PCV) maps is indispensable. For LEO GPS receivers, often a-priori PCV maps are obtained by a pre-launch ground campaign, which is not able to represent the real space-borne environment of satellites. Therefore, in-flight calibration of the GPS antenna is more widely conducted. This paper shows that a further improvement is possible by including the so-called Code Residual Variation (CRV) maps in absolute/undifferenced and relative/Double-differenced (DD) POD schemes. Orbit solutions are produced for the GRACE satellite formation for a four months test period (August-November, 2014), demonstrating enhanced orbit precision after first using the in-flight PCV maps and a further improvement after including the CRV maps. The application of antenna maps leads to a better consistency with independent Satellite Laser Ranging (SLR) and K-band Ranging (KBR) low-low Satellite-to-Satellite Tracking (ll-SST) observations. The inclusion of the CRV maps results also in a much better consistency between reduced-dynamic and kinematic orbit solutions for especially the cross-track direction. The improvements are largest for GRACE-B, where a cross-talk between the GPS main antenna and the occultation antenna yields higher systematic observation residuals. For high-precision relative POD which necessitates DD carrier-phase ambiguity fixing, in principle frequency-dependent PCV maps would be required. To this aim, use is made of an Extended Kalman Filter (EKF) that is capable of optimizing relative spacecraft dynamics and iteratively fixing the DD carrier-phase ambiguities. It is found that PCV maps significantly improve the baseline solution. CRV maps slightly enhance the baseline precision, more significantly they lead to a much better initialization of the ambiguity fixing. The GRACE single-satellite orbit solutions compare to within a few cm 3-dimensionally with state-of-the-art external orbit solutions and SLR observations, whereas for the baseline a consistency of better than 0.7 mm with KBR observations is achieved.
The iPod binocular home-based treatment for amblyopia in adults: efficacy and compliance.
Hess, Robert F; Babu, Raiju Jacob; Clavagnier, Simon; Black, Joanna; Bobier, William; Thompson, Benjamin
2014-09-01
Occlusion therapy for amblyopia is predicated on the idea that amblyopia is primarily a disorder of monocular vision; however, there is growing evidence that patients with amblyopia have a structurally intact binocular visual system that is rendered functionally monocular due to suppression. Furthermore, we have found that a dichoptic treatment intervention designed to directly target suppression can result in clinically significant improvement in both binocular and monocular visual function in adult patients with amblyopia. The fact that monocular improvement occurs in the absence of any fellow eye occlusion suggests that amblyopia is, in part, due to chronic suppression. Previously the treatment has been administered as a psychophysical task and more recently as a video game that can be played on video goggles or an iPod device equipped with a lenticular screen. The aim of this case-series study of 14 amblyopes (six strabismics, six anisometropes and two mixed) ages 13 to 50 years was to investigate: 1. whether the portable video game treatment is suitable for at-home use and 2. whether an anaglyphic version of the iPod-based video game, which is more convenient for at-home use, has comparable effects to the lenticular version. The dichoptic video game treatment was conducted at home and visual functions assessed before and after treatment. We found that at-home use for 10 to 30 hours restored simultaneous binocular perception in 13 of 14 cases along with significant improvements in acuity (0.11 ± 0.08 logMAR) and stereopsis (0.6 ± 0.5 log units). Furthermore, the anaglyph and lenticular platforms were equally effective. In addition, the iPod devices were able to record a complete and accurate picture of treatment compliance. The home-based dichoptic iPod approach represents a viable treatment for adults with amblyopia. © 2014 The Authors. Clinical and Experimental Optometry © 2014 Optometrists Association Australia.
Estimating cetacean carrying capacity based on spacing behaviour.
Braithwaite, Janelle E; Meeuwig, Jessica J; Jenner, K Curt S
2012-01-01
Conservation of large ocean wildlife requires an understanding of how they use space. In Western Australia, the humpback whale (Megaptera novaeangliae) population is growing at a minimum rate of 10% per year. An important consideration for conservation based management in space-limited environments, such as coastal resting areas, is the potential expansion in area use by humpback whales if the carrying capacity of existing areas is exceeded. Here we determined the theoretical carrying capacity of a known humpback resting area based on the spacing behaviour of pods, where a resting area is defined as a sheltered embayment along the coast. Two separate approaches were taken to estimate this distance. The first used the median nearest neighbour distance between pods in relatively dense areas, giving a spacing distance of 2.16 km (± 0.94). The second estimated the spacing distance as the radius at which 50% of the population included no other pods, and was calculated as 1.93 km (range: 1.62-2.50 km). Using these values, the maximum number of pods able to fit into the resting area was 698 and 872 pods, respectively. Given an average observed pod size of 1.7 whales, this equates to a carrying capacity estimate of between 1187 and 1482 whales at any given point in time. This study demonstrates that whale pods do maintain a distance from each other, which may determine the number of animals that can occupy aggregation areas where space is limited. This requirement for space has implications when considering boundaries for protected areas or competition for space with the fishing and resources sectors.
Hoopen, G Martijn ten; Rees, Robert; Aisa, Philo; Stirrup, Tim; Krauss, Ulrike
2003-05-01
Mycoparasites collected from aerial parts of the cocoa plant (Theobroma cacao) have shown great promise in the control of black pod, caused by Phytophthora palmivora, and moniliasis, caused by Moniliophthora roreri. However, the ecology of epiphytic mycoparasites is still poorly understood although it has a direct bearing on applied biocontrol practices, ranging from the identification and isolation of promising biocontrol candidates to formulation needs and required application frequency. One objective of this study was to determine the natural abundance of mycoparasites on cocoa flowers and pods in relation to crop development stage and cultivar. For this purpose, native mycoparasites were detected on cocoa flowers and pods using the precolonised plate baiting technique. Furthermore, the survival of an applied Clonostachys rosea isolate on cocoa pods on shaded and non-shaded trees was compared as well as the recolonisation patterns of surface-sterilised pods by native mycoparasites under these conditions. Clonostachys spp. were the most commonly isolated native mycoparasites, followed by Fusarium spp. No differences in the occurrence of native, epiphytic mycoparasites were observed between the three main cocoa cultivars, 'Criollo', 'Forastero' and 'Trinitario', nor between clones within these groups. Thus, a single biocontrol inoculum can be suitable for application to cultivar mixtures of cocoa commonly grown together in a field. Different susceptibility classes of segregating F1 populations of hybrids with resistance against M. roreri and P. palmivora supported similar population levels and taxonomic assemblages of mycoparasites. Therefore, we reject the hypothesis that these antagonists mediate resistance. Mycoparasite abundance and genetic disease resistance to black pod and moniliasis are independent phenomena and should lead to additive effects if employed simultaneously in an integrated disease management programme. The survival of applied C. rosea was not affected by the shading regime or any other meteorological parameter measured. On the other hand, recolonisation of surface-sterilised cocoa pods by most native mycoparasites was faster in the shade. Only Trichoderma spp. colonised pods exposed to direct sunlight faster than shaded ones. The implications for the design of biocontrol inocula and formulation technology are discussed.
USDA-ARS?s Scientific Manuscript database
Among the Phytophthora species that cause black pod of cacao, P. megakarya is the most virulent, posing a serious threat to cacao production in Africa. Correct identification of the species causing the black pod and understanding the virulence factors involved are important for developing sustainabl...
The effects of iPod and text-messaging use on driver distraction: a bio-behavioral analysis.
Mouloua, M; Ahern, A; Quevedo, A; Jaramillo, D; Rinalducci, E; Smither, J; Alberti, P; Brill, C
2012-01-01
This study was designed to empirically examine the effects of iPod device and text-messaging activities on driver distraction. Sixty participants were asked to perform a driving simulation task while searching for songs using an iPod device or text messaging. Driving errors as measured by lane deviations were recorded and analyzed as a function of the distracters. Physiological measures (EEG) were also recorded during the driving phases in order to measure participant levels of cortical arousal. It was hypothesized that iPod use and text messaging would result in a profound effect on driving ability. The results showed a significant effect of iPod use and text-messaging on driving performance. Increased numbers of driving errors were recorded during the iPod and text-messaging phases than the pre- and post-allocation phases. Higher levels of Theta activity were also observed during the iPod and Text-messaging phase than the pre- and post-allocation phases. Implications for in-vehicle systems design, training, and safety are also discussed.
Laundry detergent pod ingestions: is there a need for endoscopy?
Smith, Erika; Liebelt, Erica; Nogueira, Jan
2014-09-01
Laundry detergent pod (LDP) exposures in children have resulted in several referrals to the emergency department. Signs and symptoms can include gastrointestinal symptoms (vomiting, drooling), neurological symptoms (depressed sensorium), or metabolic changes (lactic acidosis). There is limited literature on esophageal injury following LDP ingestions. We reviewed three cases of pediatric LDP ingestions that underwent an upper endoscopy in a tertiary care pediatric hospital. All of our patients were younger than 3 years old. The upper endoscopies revealed superficial esophageal erosions in two patients and erythema in the other. None of the patients had oral burns. Two of them developed swallowing dysfunction. Follow-up upper GI studies were normal. Our three patients ingested laundry detergent pods and all of them developed some degree of esophageal injury despite the absence of oral erythema, ulcers, or swelling. A review of literature suggests LDP exposures are more severe than non-pod detergents. Reasons as to why this may be remain unclear, although investigation into the ingredients and mode of delivery may help us to better understand. In a literature review, no esophageal strictures have been reported after LDP ingestion. We reviewed esophageal injury classification systems in an attempt to predict who may be at greatest risk for stricture based on initial findings. Our case series demonstrates it is hard to predict esophageal injury based on signs and symptoms. Based on a literature review, long-term esophageal stricture is unlikely, but if gastrointestinal symptoms persist, it is reasonable to evaluate with an upper endoscopy. Larger studies are needed.
FORMOSAT-3/COSMIC POD Data Processing and Initial Results
NASA Astrophysics Data System (ADS)
Tang, C.
2006-12-01
The six satellites of the collaborative Taiwan-U.S. FORMOSAT-3/COSMIC (Constellation Observing System for Meteorology, Ionosphere, and Climate) space program were successfully launched from Vandenberg, U.S.A. on April 15, 2006. As of September 7, 2006, one satellite (FM5) has already been transferred to the 800-km final orbit, while the other five satellites (FM1-4 and FM6) are currently waiting in the ~520-km parking orbit for subsequent orbit raising deployment. There are two GPS antennas with different orientation onboard each satellite whose measurements are used specifically for precise orbit determination (POD). The received GPS signals by the POD antennas were rather sparse and unstable in the initial 5 weeks. Since then, the available GPS measurements have gradually increased from 10-20% in the early stage to almost 90% in 11 weeks after the launch. For the two POD antennas (POD+X and POD-X), one antenna can perform normally and record observations from up to 9 GPS satellites in view; however, the other antenna is programmed to track up to 4 GPS satellites due to onboard memory limitation. For this reason, we first performed orbit computation using zero-difference GPS phases collected by the normal antenna. For each day's orbit computation, we designed a 6-hr (25%) overlap for inner orbital accuracy assessment, and overlap analysis shows that the achievable 3D RMS was around 19 cm, or 11 cm per axis. In a separate effort, orbit computation based on the lesser antenna was also performed. The orbital difference between the results obtained from the two antennas was significant, with a 3D RMS value of 64 cm. The early results indicate that more work is needed in order to incorporate GPS data from both antennas into a unified solution.
POD evaluation using simulation: A phased array UT case on a complex geometry part
NASA Astrophysics Data System (ADS)
Dominguez, Nicolas; Reverdy, Frederic; Jenson, Frederic
2014-02-01
The use of Probability of Detection (POD) for NDT performances demonstration is a key link in products lifecycle management. The POD approach is to apply the given NDT procedure on a series of known flaws to estimate the probability to detect with respect to the flaw size. A POD is relevant if and only if NDT operations are carried out within the range of variability authorized by the procedure. Such experimental campaigns require collection of large enough datasets to cover the range of variability with sufficient occurrences to build a reliable POD statistics, leading to expensive costs to get POD curves. In the last decade research activities have been led in the USA with the MAPOD group and later in Europe with the SISTAE and PICASSO projects based on the idea to use models and simulation tools to feed POD estimations. This paper proposes an example of application of POD using simulation on the inspection procedure of a complex -full 3D- geometry part using phased arrays ultrasonic testing. It illustrates the methodology and the associated tools developed in the CIVA software. The paper finally provides elements of further progress in the domain.
Problem-oriented drug information: physicians' expectations and impact on clinical practice.
Hedegaard, U; Damkier, P
2009-05-01
Problem-oriented drug information (POD) is a service in which health professionals provide evidence-based answers to clinical questions posed by physicians. The objective of this study was to evaluate the user satisfaction and clinical impact of POD, to investigate predictors for use and to examine the kind of sources physicians search before applying for POD. To evaluate POD, a questionnaire was distributed with problem-oriented answers sent from a drug information centre to physicians during the period of April 2006 to March 2007. Of 197 questionnaires, 183 (93%) were returned. The information from the POD service was highly valued by the physicians, and 90% of the answers led to reported impact on clinical practice in the specific clinical situation. Furthermore, 74% of the answers were intended to be used in a wider context either for future patients (67%) or for dissemination to colleagues (51%). Secondary-care physicians more often than general practitioners (GPs) used the information for dissemination to colleagues (63 vs. 39%, P = 0.0008), while GPs more often used the answer to support patient information (88 vs. 70%, P = 0.0029). The most prominent motive for applying for POD was a request for evidence-based information (78%), and the service was used to overcome barriers to practicing evidence-based medicine such as lack of time (36%), skills for searching (26%), and appraising the literature (13%). Before inquiring, 74% of the physicians had tried other information sources; the most frequent sources used were a drug reference (68%) and consulting a colleague (24%). Secondary-care physicians reported fewer barriers than GPs when seeking information, and secondary-care physicians searched other sources more often than GPs before contacting the service (81 vs. 67%, P = 0.031). POD represents a useful source for acquiring evidence-based drug information by physicians. POD is highly valued by the users. It was reported to have an impact on clinical practice for the specific patient but is also intended to be used in a wider context for future patients or for dissemination to colleagues. GPs' and secondary-care physicians' use of POD differs with GPs having more focus on patient information and secondary-care physicians having more focus on dissemination of the information to colleagues.
Schultz, Elise V; Schultz, Christopher J; Carey, Lawrence D; Cecil, Daniel J; Bateman, Monte
2016-01-01
This study develops a fully automated lightning jump system encompassing objective storm tracking, Geostationary Lightning Mapper proxy data, and the lightning jump algorithm (LJA), which are important elements in the transition of the LJA concept from a research to an operational based algorithm. Storm cluster tracking is based on a product created from the combination of a radar parameter (vertically integrated liquid, VIL), and lightning information (flash rate density). Evaluations showed that the spatial scale of tracked features or storm clusters had a large impact on the lightning jump system performance, where increasing spatial scale size resulted in decreased dynamic range of the system's performance. This framework will also serve as a means to refine the LJA itself to enhance its operational applicability. Parameters within the system are isolated and the system's performance is evaluated with adjustments to parameter sensitivity. The system's performance is evaluated using the probability of detection (POD) and false alarm ratio (FAR) statistics. Of the algorithm parameters tested, sigma-level (metric of lightning jump strength) and flash rate threshold influenced the system's performance the most. Finally, verification methodologies are investigated. It is discovered that minor changes in verification methodology can dramatically impact the evaluation of the lightning jump system.
NASA Technical Reports Server (NTRS)
Schultz, Elise; Schultz, Christopher Joseph; Carey, Lawrence D.; Cecil, Daniel J.; Bateman, Monte
2016-01-01
This study develops a fully automated lightning jump system encompassing objective storm tracking, Geostationary Lightning Mapper proxy data, and the lightning jump algorithm (LJA), which are important elements in the transition of the LJA concept from a research to an operational based algorithm. Storm cluster tracking is based on a product created from the combination of a radar parameter (vertically integrated liquid, VIL), and lightning information (flash rate density). Evaluations showed that the spatial scale of tracked features or storm clusters had a large impact on the lightning jump system performance, where increasing spatial scale size resulted in decreased dynamic range of the system's performance. This framework will also serve as a means to refine the LJA itself to enhance its operational applicability. Parameters within the system are isolated and the system's performance is evaluated with adjustments to parameter sensitivity. The system's performance is evaluated using the probability of detection (POD) and false alarm ratio (FAR) statistics. Of the algorithm parameters tested, sigma-level (metric of lightning jump strength) and flash rate threshold influenced the system's performance the most. Finally, verification methodologies are investigated. It is discovered that minor changes in verification methodology can dramatically impact the evaluation of the lightning jump system.
Instrument Development of Real Time Holographic Water Drop Size Measurement System
DOE Office of Scientific and Technical Information (OSTI.GOV)
Springston, Stephen
2007-02-09
BNL participated with multiple correspondences with Physical Optics Corporation (POC) on the design considerations of an airbome instrument. A pod for extemal deployment ofthe POC unit on the DOE Research Aircraft Facility (RAF), an instrumented, Grumman G-1 aircraft was loaned to POC. BNL proposed evaluation flight tests between the POC unit and the BNL Cloud Aerosol Probe Spectrometer (CAPS) as a reference method. BNL's involvement is described in the semi-annual report ofPOC to DOE. Because of unanticipated technical and engineering difficulties, POC was unable to fit their instrument into an aircraft pod. As a result they are now focusing onmore » a ground-based version first. A prototype laboratory version of the Real-Time Holographic Water Drop Size Measurement (WDSM) System has been constructed.« less
Flow temporal reconstruction from non-time-resolved data part I: mathematic fundamentals
NASA Astrophysics Data System (ADS)
Legrand, Mathieu; Nogueira, José; Lecuona, Antonio
2011-10-01
At least two circumstances point to the need of postprocessing techniques to recover lost time information from non-time-resolved data: the increasing interest in identifying and tracking coherent structures in flows of industrial interest and the high data throughput of global measuring techniques, such as PIV, for the validation of computational fluid dynamics (CFD) codes. This paper offers the mathematic fundamentals of a space--time reconstruction technique from non-time-resolved, statistically independent data. An algorithm has been developed to identify and track traveling coherent structures in periodic flows. Phase-averaged flow fields are reconstructed with a correlation-based method, which uses information from the Proper Orthogonal Decomposition (POD). The theoretical background shows that the snapshot POD coefficients can be used to recover flow phase information. Once this information is recovered, the real snapshots are used to reconstruct the flow history and characteristics, avoiding neither the use of POD modes nor any associated artifact. The proposed time reconstruction algorithm is in agreement with the experimental evidence given by the practical implementation proposed in the second part of this work (Legrand et al. in Exp Fluids, 2011), using the coefficients corresponding to the first three POD modes. It also agrees with the results on similar issues by other authors (Ben Chiekh et al. in 9 Congrès Francophone de Vélocimétrie Laser, Bruxelles, Belgium, 2004; Van Oudheusden et al. in Exp Fluids 39-1:86-98, 2005; Meyer et al. in 7th International Symposium on Particle Image Velocimetry, Rome, Italy, 2007a; in J Fluid Mech 583:199-227, 2007b; Perrin et al. in Exp Fluids 43-2:341-355, 2007). Computer time to perform the reconstruction is relatively short, of the order of minutes with current PC technology.
Dynamics of flow control in an emulated boundary layer-ingesting offset diffuser
NASA Astrophysics Data System (ADS)
Gissen, A. N.; Vukasinovic, B.; Glezer, A.
2014-08-01
Dynamics of flow control comprised of arrays of active (synthetic jets) and passive (vanes) control elements , and its effectiveness for suppression of total-pressure distortion is investigated experimentally in an offset diffuser, in the absence of internal flow separation. The experiments are conducted in a wind tunnel inlet model at speeds up to M = 0.55 using approach flow conditioning that mimics boundary layer ingestion on a Blended-Wing-Body platform. Time-dependent distortion of the dynamic total-pressure field at the `engine face' is measured using an array of forty total-pressure probes, and the control-induced distortion changes are analyzed using triple decomposition and proper orthogonal decomposition (POD). These data indicate that an array of the flow control small-scale synthetic jet vortices merge into two large-scale, counter-rotating streamwise vortices that exert significant changes in the flow distortion. The two most energetic POD modes appear to govern the distortion dynamics in either active or hybrid flow control approaches. Finally, it is shown that the present control approach is sufficiently robust to reduce distortion with different inlet conditions of the baseline flow.
Model-based POD study of manual ultrasound inspection and sensitivity analysis using metamodel
NASA Astrophysics Data System (ADS)
Ribay, Guillemette; Artusi, Xavier; Jenson, Frédéric; Reece, Christopher; Lhuillier, Pierre-Emile
2016-02-01
The reliability of NDE can be quantified by using the Probability of Detection (POD) approach. Former studies have shown the potential of the model-assisted POD (MAPOD) approach to replace expensive experimental determination of POD curves. In this paper, we make use of CIVA software to determine POD curves for a manual ultrasonic inspection of a heavy component, for which a whole experimental POD campaign was not available. The influential parameters were determined by expert analysis. The semi-analytical models used in CIVA for wave propagation and beam-defect interaction have been validated in the range of variation of the influential parameters by comparison with finite element modelling (Athena). The POD curves are computed for « hit/miss » and « â versus a » analysis. The verification of Berens hypothesis is evaluated by statistical tools. A sensitivity study is performed to measure the relative influence of parameters on the defect response amplitude variance, using the Sobol sensitivity index. A meta-model is also built to reduce computing cost and enhance the precision of estimated index.
Reduced-Order Modeling: Cooperative Research and Development at the NASA Langley Research Center
NASA Technical Reports Server (NTRS)
Silva, Walter A.; Beran, Philip S.; Cesnik, Carlos E. S.; Guendel, Randal E.; Kurdila, Andrew; Prazenica, Richard J.; Librescu, Liviu; Marzocca, Piergiovanni; Raveh, Daniella E.
2001-01-01
Cooperative research and development activities at the NASA Langley Research Center (LaRC) involving reduced-order modeling (ROM) techniques are presented. Emphasis is given to reduced-order methods and analyses based on Volterra series representations, although some recent results using Proper Orthogonal Deco in position (POD) are discussed as well. Results are reported for a variety of computational and experimental nonlinear systems to provide clear examples of the use of reduced-order models, particularly within the field of computational aeroelasticity. The need for and the relative performance (speed, accuracy, and robustness) of reduced-order modeling strategies is documented. The development of unsteady aerodynamic state-space models directly from computational fluid dynamics analyses is presented in addition to analytical and experimental identifications of Volterra kernels. Finally, future directions for this research activity are summarized.
Webster, A. Francina; Chepelev, Nikolai; Gagné, Rémi; Kuo, Byron; Recio, Leslie; Williams, Andrew; Yauk, Carole L.
2015-01-01
Many regulatory agencies are exploring ways to integrate toxicogenomic data into their chemical risk assessments. The major challenge lies in determining how to distill the complex data produced by high-content, multi-dose gene expression studies into quantitative information. It has been proposed that benchmark dose (BMD) values derived from toxicogenomics data be used as point of departure (PoD) values in chemical risk assessments. However, there is limited information regarding which genomics platforms are most suitable and how to select appropriate PoD values. In this study, we compared BMD values modeled from RNA sequencing-, microarray-, and qPCR-derived gene expression data from a single study, and explored multiple approaches for selecting a single PoD from these data. The strategies evaluated include several that do not require prior mechanistic knowledge of the compound for selection of the PoD, thus providing approaches for assessing data-poor chemicals. We used RNA extracted from the livers of female mice exposed to non-carcinogenic (0, 2 mg/kg/day, mkd) and carcinogenic (4, 8 mkd) doses of furan for 21 days. We show that transcriptional BMD values were consistent across technologies and highly predictive of the two-year cancer bioassay-based PoD. We also demonstrate that filtering data based on statistically significant changes in gene expression prior to BMD modeling creates more conservative BMD values. Taken together, this case study on mice exposed to furan demonstrates that high-content toxicogenomics studies produce robust data for BMD modelling that are minimally affected by inter-technology variability and highly predictive of cancer-based PoD doses. PMID:26313361
American Carrier Air Power at the Dawn of a New Century
2005-01-01
Systems, Office of the Secretary of Defense (Operational Test and Evaluation); then–Commander Calvin Craig, OPNAV N81; Captain Kenneth Neubauer and...TACP Tactical Air Control Party TARPS Tactical Air Reconnaissance Pod System TCS Television Camera System TLAM Tomahawk Land-Attack Missile TST Time...store any video imagery acquired by the aircraft’s systems, including the TARPS pod, the pilot’s head-up display (HUD), the Television Camera System (TCS
NASA Astrophysics Data System (ADS)
Blanchard, Antoine; Bergman, Lawrence A.; Vakakis, Alexander F.
2017-07-01
We computationally investigate the dynamics of a linearly-sprung circular cylinder immersed in an incompressible flow and undergoing transverse vortex-induced vibration (VIV), to which is attached a rotational nonlinear energy sink (NES) consisting of a mass that freely rotates at constant radius about the cylinder axis, and whose motion is restrained by a rotational linear viscous damper. The inertial coupling between the rotational motion of the attached mass and the rectilinear motion of the cylinder is ;essentially nonlinear;, which, in conjunction with dissipation, allows for one-way, nearly irreversible targeted energy transfer (TET) from the oscillating cylinder to the nonlinear dissipative attachment. At the intermediate Reynolds number Re = 100, the NES-equipped sprung cylinder undergoes repetitive cycles of slowly decaying oscillations punctuated by intervals of chaotic instabilities. During the slowly decaying portion of each cycle, the dynamics of the cylinder is regular and, for large enough values of the ratio ε of the NES mass to the total mass (i.e., NES mass plus cylinder mass), can lead to significant vortex street elongation with partial stabilization of the wake. As ε approaches zero, no such vortex elongation is observed and the wake patterns appear similar to that for a sprung cylinder with no NES. We apply proper orthogonal decomposition (POD) to the velocity flow field during a slowly decaying portion of the solution and show that, in situations where vortex elongation occurs, the NES, though not in direct contact with the surrounding fluid, has a drastic effect on the underlying flow structures, imparting significant and continuous passive redistribution of energy among POD modes. We construct a POD-based reduced-order model for the lift coefficient to characterize energy transactions between the fluid and the cylinder throughout the slowly decaying cycle. We introduce a quantitative signed measure of the work done by the fluid on the cylinder over one quasi-period of the slowly decaying response and find that vortex elongation is associated with a sign change of that measure, indicating that a reversal of the direction of energy transfer, with the cylinder ;leaking energy back; to the flow, is responsible for partial stabilization and elongation of the wake. We interpret these findings in terms of the spatial structure and energy distribution of the POD modes, and relate them to the mechanism of transient resonance capture into a slow invariant manifold of the fluid-structure interaction dynamics.
2012-06-12
CAPE CANAVERAL, Fla. – In Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, an orbital maneuvering system, or OMS, pod is lifted from its transporter under the careful supervision of United Space Alliance technicians. The pod will be reinstalled on space shuttle Atlantis. The orbital maneuvering system provided the shuttle with thrust for orbit insertion, rendezvous and deorbit, and could provide up to 1,000 pounds of propellant to the aft reaction control system. The OMS is housed in two independent pods located on each side of the shuttle's aft fuselage. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers. Atlantis’ OMS pods were removed and sent to White Sands Test Facility in New Mexico to be cleaned of residual toxic propellant. The work is part of the Space Shuttle Program’s transition and retirement processing of the shuttle fleet. A groundbreaking was held Jan. 18 for Atlantis' future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/transition. Photo credit: NASA/Kim Shiflett
Recce NG: from Recce sensor to image intelligence (IMINT)
NASA Astrophysics Data System (ADS)
Larroque, Serge
2001-12-01
Recce NG (Reconnaissance New Generation) is presented as a complete and optimized Tactical Reconnaissance System. Based on a new generation Pod integrating high resolution Dual Band sensors, the system has been designed with the operational lessons learnt from the last Peace Keeping Operations in Bosnia and Kosovo. The technical solutions retained as component modules of a full IMINT acquisition system, take benefit of the state of art in the following key technologies: Advanced Mission Planning System for long range stand-off Manned Recce, Aircraft and/or Pod tasking, operating sophisticated back-up software tools, high resolution 3D geo data and improved/combat proven MMI to reduce planning delays, Mature Dual Band sensors technology to achieve the Day and Night Recce Mission, including advanced automatic operational functions, as azimuth and roll tracking capabilities, low risk in Pod integration and in carrier avionics, controls and displays upgrades, to save time in operational turn over and maintenance, High rate Imagery Down Link, for Real Time or Near Real Time transmission, fully compatible with STANAG 7085 requirements, Advanced IMINT Exploitation Ground Segment, combat proven, NATO interoperable (STANAG 7023), integrating high value software tools for accurate location, improved radiometric image processing and open link to the C4ISR systems. The choice of an industrial Prime contractor mastering across the full system, all the prior listed key products and technologies, is mandatory to a successful delivery in terms of low Cost, Risk and Time Schedule.
Structural Loading on the QCM/SAW Instrument Aboard the ER-2 Used for Atmospheric Testing
NASA Technical Reports Server (NTRS)
Bainum, Peter M.; Jones, Phyllis D.; Irish, Sandra M.; Xing, Guang-Qian
1998-01-01
Several experiments have been proposed to capture and evaluate samples of the atmosphere where SST's travel. One means to achieve this is to utilize the quartz crystal microbalance (QCM) / surface acoustical wave (SAW) instrument installed aboard the ER-2, formerly the U-2 reconnaissance aircraft. The QCM is a cascade impactor designed to perform in-situ, real-time measurements of aerosols and chemical vapors at an altitude of 60,000-70,000 feet. The primary use of the ER-2 is by NASA for Earth resources to test new sensor systems before being placed aboard satellites. One of the main reasons the ER-2 is used for this flight experiment is its capability to fly approximately twelve miles above the sea level (can reach an altitude of 78,000 feet). Because the ER-2 operates at such a high altitude, it is of special interest to scientists interested in space exploration or supersonic aircraft. The purpose of some of the experiments is to extinct data from the atmosphere around the ER-2. For the current CSTEA flight experiment, the housing of the QCM is in a frame that connects to an outer pod that attaches to the fuselage of the ER-2. Due to the location of the QCM within the housing frame and the location of the pod on the ER-2, the pod and its contents are subject to structural loads. In addition to structural loads, structural vibrations are also of importance because the QCM output data is based on the determination of beat frequencies between a pair of oscillators (one coated, the second uncoated, according to the chemical reaction being monitored). A structural analysis of this system can indicate whether potential resonances may exist between the (higher) structural modal frequencies and the beat frequencies. In addition undesirable deformations may result due to maximum expected static or dynamic loads during typical flight conditions. If the deformations are excessive they may adversely affect the accuracy the instrumentation output.
Modal decomposition of turbulent supersonic cavity
NASA Astrophysics Data System (ADS)
Soni, R. K.; Arya, N.; De, A.
2018-06-01
Self-sustained oscillations in a Mach 3 supersonic cavity with a length-to-depth ratio of three are investigated using wall-modeled large eddy simulation methodology for ReD = 3.39× 105 . The unsteady data obtained through computation are utilized to investigate the spatial and temporal evolution of the flow field, especially the second invariant of the velocity tensor, while the phase-averaged data are analyzed over a feedback cycle to study the spatial structures. This analysis is accompanied by the proper orthogonal decomposition (POD) data, which reveals the presence of discrete vortices along the shear layer. The POD analysis is performed in both the spanwise and streamwise planes to extract the coherence in flow structures. Finally, dynamic mode decomposition is performed on the data sequence to obtain the dynamic information and deeper insight into the self-sustained mechanism.
Dong, Rui; Dong, Deke; Luo, Dong; Zhou, Qiang; Chai, Xutian; Zhang, Jiyu; Xie, Wengang; Liu, Wenxian; Dong, Yang; Wang, Yanrong; Liu, Zhipeng
2017-01-01
The seed dispersion caused by pod shattering is a form of propagation used by many wild species. Loss of seeds from pod shattering is frequent in the common vetch (Vicia sativa L.), an important self-pollinating annual forage legume. However, pod shattering is one of the most important defects that limits the reproduction of the vetch in the field and the usage as a leguminous forage crop. To better understand the vetch pod shattering mechanism, we used high-throughput RNA sequencing to assess the global changes in the transcriptomes of the pod ventral sutures of shattering-susceptible and shattering-resistant vetch accessions screened from 541 vetch germplasms. A total of 1,285 significantly differentially expressed unigenes (DEGs) were detected, including 575 up-regulated unigenes and 710 down-regulated unigenes. Analyses of Gene Ontology and KEGG metabolic enrichment pathways of 1,285 DEGs indicated that 22 DEGs encoding cell wall modifications and hydrolases associated with pod shattering were highly expressed in shattering-susceptible accessions. These genes were mainly enriched in “hydrolase activity,” “cytoplasm,” and “carbohydrate metabolic process” systems. These cell wall modifications and hydrolases genes included β-glucosidase and endo-polygalacturonase, which work together to break down the glycosidic bonds of pectin and cellulose, and to promote the dissolution and disappearance of the cell wall in the ventral suture of the pod and make the pod more susceptible to shattering. We demonstrated the differences in gene transcription levels between the shattering-susceptible and shattering-resistant vetch accessions for the first time and our results provided valuable information for the identifying and characterizing of pod shattering regulation networks in vetch. This information may facilitate the future identification of pod shattering-related genes and their underlying molecular mechanisms in the common vetch. PMID:28496452
Internet's impact on publishing
NASA Astrophysics Data System (ADS)
Beretta, Giordano B.
1997-04-01
In 1990, the first monochrome print-on-demand (POD) systems wee successfully brought to market. Subsequent color versions have been less successful, in my view mostly because they require a different workflow than traditional systems and the highly skilled specialists have not been trained. This hypothesis is based on the observation that direct-to-plate systems for short run printing, which do not require a new workflow, are quite successful in the market place. The internet and the World Wide Web are the enabling technologies that are fostering a new print model that is very likely to replace color POD before the latter can establish itself. In this model the consumers locate the material they desire from a contents provider, pay through a digital cash clearinghouse, and print the material at their own cost on their local printer. All the basic technologies for this model are in place; the main challenge is to make the workflow sufficiently robust for individual use.
Flow Scales of Influence on the Settling Velocities of Particles with Varying Characteristics
Jacobs, Corrine N.; Merchant, Wilmot; Jendrassak, Marek; Limpasuvan, Varavut; Gurka, Roi; Hackett, Erin E.
2016-01-01
The settling velocities of natural, synthetic, and industrial particles were measured in a grid turbulence facility using optical measurement techniques. Particle image velocimetry and 2D particle tracking were used to measure the instantaneous velocities of the flow and the particles’ trajectories simultaneously. We find that for particles examined in this study (Rep = 0.4–123), settling velocity is either enhanced or unchanged relative to stagnant flow for the range of investigated turbulence conditions. The smallest particles’ normalized settling velocities exhibited the most consistent trends when plotted versus the Kolmogorov-based Stokes numbers suggesting that the dissipative scales influence their dynamics. In contrast, the mid-sized particles were better characterized with a Stokes number based on the integral time scale. The largest particles were largely unaffected by the flow conditions. Using proper orthogonal decomposition (POD), the flow pattern scales are compared to particle trajectory curvature to complement results obtained through dimensional analysis using Stokes numbers. The smallest particles are found to have trajectories with curvatures of similar scale as the small flow scales (higher POD modes) whilst mid-sized particle trajectories had curvatures that were similar to the larger flow patterns (lower POD modes). The curvature trajectories of the largest particles did not correspond to any particular flow pattern scale suggesting that their trajectories were more random. These results provide experimental evidence of the “fast tracking” theory of settling velocity enhancement in turbulence and demonstrate that particles align themselves with flow scales in proportion to their size. PMID:27513958
Guthrie, Kate M; Rosen, Rochelle K; Vargas, Sara E; Getz, Melissa L; Dawson, Lauren; Guillen, Melissa; Ramirez, Jaime J; Baum, Marc M; Vincent, Kathleen L
2018-01-01
Effective HIV prevention requires efficient delivery of safe and efficacious drugs and optimization of user adherence. The user's experiences with the drug, delivery system, and use parameters are critical to product acceptability and adherence. Prevention product developers have the opportunity to directly control a drug delivery system and its impact on acceptability and adherence, as well as product efficacy. Involvement of potential users during preclinical design and development can facilitate this process. We embedded a mixed methods user evaluation study into a safety and pharmacokinetics (PK) trial of a pod-intravaginal ring delivering antiretroviral agents. Women enrolled in two cohorts, ultimately evaluating the safety/PK of a pod-IVRs delivering TDF-alone, TDF-FTC, and/or TDF-FTC-MVC. A 7-day use period was targeted for each pod-IVR, regardless of drug or drug combination. During the clinical study, participants provided both quantitative (i.e., survey) and qualitative (i.e., in-depth interview) data capturing acceptability, perceptibility, and adherence behaviors. Initial sexual and reproductive health history surveys, daily diaries, a final acceptability and willingness to use survey, and a qualitative in-depth interview comprised the user evaluation data for each pod-IVR experienced by the participants. Overall, the majority of participants (N = 10) reported being willing to use the pod-IVR platform for HIV prevention should it advance to market. Confidence to use the pod-IVR (e.g., insertion, removal) was high. There were no differences noted in the user experience of the pod-IVR platform; that is, whether the ring delivered TDF-alone, TDF-FTC, or TDF-FTC-MVC, users' experiences of the ring were similar and acceptable. Participants did report specific experiences, both sensory and behavioral, that impacted their use behaviors with respect to the ring, and which could ultimately impact acceptability and adherence. These experiences, and user evaluations elicited by them, could both challenge use or be used to leverage use in future trials and product rollout once fully articulated. High willingness-to-use data and lack of salient differences in user experiences related to use of the pod-IVR platform (regardless of agents delivered) suggests that the pod-IVR is a feasible and acceptable drug delivery device in and of itself. This finding holds promise both for an anti-HIV pod-IVR and, potentially, a multipurpose prevention pod-IVR that could deliver both prevention for sexually transmitted infections (STIs) including HIV and contraception. Given the very early clinical trial context, further acceptability, perceptibility, and adherence data should continue to be explored, in the context of longer use periods (e.g., 28-day ring use), and in the contexts of sexual activity and menses. Using early design and development contexts to gain insights into potential challenges and facilitators of drug delivery systems such as the pod-IVR could save valuable resources and time as a potential biomedical technology moves through the clinical trial pipeline and into real-world use.
Rosen, Rochelle K.; Getz, Melissa L.; Dawson, Lauren; Guillen, Melissa; Ramirez, Jaime J.
2018-01-01
Background Effective HIV prevention requires efficient delivery of safe and efficacious drugs and optimization of user adherence. The user’s experiences with the drug, delivery system, and use parameters are critical to product acceptability and adherence. Prevention product developers have the opportunity to directly control a drug delivery system and its impact on acceptability and adherence, as well as product efficacy. Involvement of potential users during preclinical design and development can facilitate this process. We embedded a mixed methods user evaluation study into a safety and pharmacokinetics (PK) trial of a pod-intravaginal ring delivering antiretroviral agents. Methodology Women enrolled in two cohorts, ultimately evaluating the safety/PK of a pod-IVRs delivering TDF-alone, TDF-FTC, and/or TDF-FTC-MVC. A 7-day use period was targeted for each pod-IVR, regardless of drug or drug combination. During the clinical study, participants provided both quantitative (i.e., survey) and qualitative (i.e., in-depth interview) data capturing acceptability, perceptibility, and adherence behaviors. Initial sexual and reproductive health history surveys, daily diaries, a final acceptability and willingness to use survey, and a qualitative in-depth interview comprised the user evaluation data for each pod-IVR experienced by the participants. Findings Overall, the majority of participants (N = 10) reported being willing to use the pod-IVR platform for HIV prevention should it advance to market. Confidence to use the pod-IVR (e.g., insertion, removal) was high. There were no differences noted in the user experience of the pod-IVR platform; that is, whether the ring delivered TDF-alone, TDF-FTC, or TDF-FTC-MVC, users’ experiences of the ring were similar and acceptable. Participants did report specific experiences, both sensory and behavioral, that impacted their use behaviors with respect to the ring, and which could ultimately impact acceptability and adherence. These experiences, and user evaluations elicited by them, could both challenge use or be used to leverage use in future trials and product rollout once fully articulated. Conclusions High willingness-to-use data and lack of salient differences in user experiences related to use of the pod-IVR platform (regardless of agents delivered) suggests that the pod-IVR is a feasible and acceptable drug delivery device in and of itself. This finding holds promise both for an anti-HIV pod-IVR and, potentially, a multipurpose prevention pod-IVR that could deliver both prevention for sexually transmitted infections (STIs) including HIV and contraception. Given the very early clinical trial context, further acceptability, perceptibility, and adherence data should continue to be explored, in the context of longer use periods (e.g., 28-day ring use), and in the contexts of sexual activity and menses. Using early design and development contexts to gain insights into potential challenges and facilitators of drug delivery systems such as the pod-IVR could save valuable resources and time as a potential biomedical technology moves through the clinical trial pipeline and into real-world use. PMID:29758049
Precise orbit determination of Multi-GNSS constellation including GPS GLONASS BDS and GALIEO
NASA Astrophysics Data System (ADS)
Dai, Xiaolei
2014-05-01
In addition to the existing American global positioning system (GPS) and the Russian global navigation satellite system (GLONASS), the new generation of GNSS is emerging and developing, such as the Chinese BeiDou satellite navigation system (BDS) and the European GALILEO system. Multi-constellation is expected to contribute to more accurate and reliable positioning and navigation service. However, the application of multi-constellation challenges the traditional precise orbit determination (POD) strategy that was designed usually for single constellation. In this contribution, we exploit a more rigorous multi-constellation POD strategy for the ongoing IGS multi-GNSS experiment (MGEX) where the common parameters are identical for each system, and the frequency- and system-specified parameters are employed to account for the inter-frequency and inter-system biases. Since the authorized BDS attitude model is not yet released, different BDS attitude model are implemented and their impact on orbit accuracy are studied. The proposed POD strategy was implemented in the PANDA (Position and Navigation Data Analyst) software and can process observations from GPS, GLONASS, BDS and GALILEO together. The strategy is evaluated with the multi-constellation observations from about 90 MGEX stations and BDS observations from the BeiDou experimental tracking network (BETN) of Wuhan University (WHU). Of all the MGEX stations, 28 stations record BDS observation, and about 80 stations record GALILEO observations. All these data were processed together in our software, resulting in the multi-constellation POD solutions. We assessed the orbit accuracy for GPS and GLONASS by comparing our solutions with the IGS final orbit, and for BDS and GALILEO by overlapping our daily orbit solution. The stability of inter-frequency bias of GLONASS and inter-system biases w.r.t. GPS for GLONASS, BDS and GALILEO were investigated. At last, we carried out precise point positioning (PPP) using the multi-constellation POD orbit and clock products, and analyzed the contribution of these POD products to PPP. Keywords: Multi-GNSS, Precise Orbit Determination, Inter-frequency bias, Inter-system bias, Precise Point Positioning
A Comprehensive Phenotypic Investigation of the "Pod-Shattering Syndrome" in Common Bean.
Murgia, Maria L; Attene, Giovanna; Rodriguez, Monica; Bitocchi, Elena; Bellucci, Elisa; Fois, Davide; Nanni, Laura; Gioia, Tania; Albani, Diego M; Papa, Roberto; Rau, Domenico
2017-01-01
Seed shattering in crops is a key domestication trait due to its relevance for seed dispersal, yield, and fundamental questions in evolution (e.g., convergent evolution). Here, we focused on pod shattering in common bean ( Phaseolus vulgaris L.), the most important legume crop for human consuption in the world. With this main aim, we developed a methodological pipeline that comprises a thorough characterization under field conditions, including also the chemical composition and histological analysis of the pod valves. The pipeline was developed based on the assumption that the shattering trait itself can be treated in principle as a "syndrome" (i.e., a set of correlated different traits) at the pod level. We characterized a population of 267 introgression lines that were developed ad-hoc to study shattering in common bean. Three main objectives were sought: (1) to dissect the shattering trait into its "components," of level (percentage of shattering pods per plant) and mode (percentage of pods with twisting or non-twisting valves); (2) to test whether shattering is associated to the chemical composition and/or the histological characteristics of the pod valves; and (3) to test the associations between shattering and other plant traits. We can conclude the following: Very high shattering levels can be achieved in different modes; shattering resistance is mainly a qualitative trait; and high shattering levels is correlated with high carbon and lignin contents of the pod valves and with specific histological charaterstics of the ventral sheath and the inner fibrous layer of the pod wall. Our data also suggest that shattering comes with a "cost," as it is associated with low pod size, low seed weight per pod, high pod weight, and low seed to pod-valves ratio; indeed, it can be more exaustively described as a syndrome at the pod level. Our work suggests that the valve chemical composition (i.e., carbon and lignin content) can be used for a high troughput phenotyping procedures for shattering phenotyping. Finally, we believe that the application of our pipeline will greatly facilitate comparative studies among legume crops, and gene tagging.
Kobayashi, Leo; Boss, Robert M; Gibbs, Frantz J; Goldlust, Eric; Hennedy, Michelle M; Monti, James E; Siegel, Nathan A
2011-01-01
Investigators studied an emergency department (ED) physical chart system and identified inconsistent, small font labeling; a single-color scheme; and an absence of human factors engineering (HFE) cues. A case study and description of the methodology with which surrogate measures of chart-related patient safety were studied and subsequently used to reduce latent hazards are presented. Medical records present a challenge to patient safety in EDs. Application of HFE can improve specific aspects of existing medical chart organization systems as they pertain to patient safety in acute care environments. During 10 random audits over 5 consecutive days (573 data points), 56 (9.8%) chart binders (range 0.0-23%) were found to be either misplaced or improperly positioned relative to other chart binders; 12 (21%) were in the critical care area. HFE principles were applied to develop an experimental chart binder system with alternating color-based chart groupings, simple and prominent identifiers, and embedded visual cues. Post-intervention audits revealed significant reductions in chart binder location problems overall (p < 0.01), for Urgent Care A and B pods (6.4% to 1.2%; p < 0.05), Fast Track C pod (19.3% to 0.0%; p < 0.05) and Behavioral/Substance Abuse D pod (15.7% to 0.0%; p < 0.05) areas of the ED. The critical care room area did not display an improvement (11.4% to 13.2%; p = 0.40). Application of HFE methods may aid the development, assessment, and modification of acute care clinical environments through evidence-based design methodologies and contribute to safe patient care delivery.
Performance estimates of a Boeing 747-100 transport mated with an outsize cargo pod
NASA Technical Reports Server (NTRS)
Jernell, L. S.
1980-01-01
The design mission performance of a Boeing 747-100 aircraft mated with an outsize cargo pod was studied. The basic design requirement was the rapid deployment of a combat loaded mobile bridge launcher from a United States east coast staging base to Europe. Weight was minimized by stripping the aircraft of unneeded, quick removal items and by utilizing graphite-epoxy composite materials for most pod components. The mission analysis was based on wind tunnel data and full scale carrier aircraft and engine data. The results are presented in tabular and graphic form.
Pod Mildew on Soybeans Can Mitigate the Damage to the Seed Arising from Field Mold at Harvest Time.
Liu, Jiang; Deng, Juncai; Zhang, Ke; Wu, Haijun; Yang, Caiqiong; Zhang, Xiaowen; Du, Junbo; Shu, Kai; Yang, Wenyu
2016-12-07
Seedpods are the outermost barrier of legume plants encountered by pests and pathogens, but research on this tissue, especially regarding their chemical constituents, is limited. In the present study, a mildew-index-model-based cluster analysis was used to evaluate and identify groups of soybean genotypes with different organ-specific resistance against field mold. The constituents of soybean pods, including proteins, carbohydrates, fatty acids, and isoflavones, were analyzed. Linear regression and correlation analyses were also conducted between these main pod constituents and the organ-specific mildew indexes of seed (MIS) and pod (MIP). With increases in the contents of infection constituents, such as proteins, carbohydrates, and fatty acids, the MIP increased and the MIS decreased. The MIS decreased with increases in the contents of glycitein (GLE)-type isoflavonoids, which act as antibiotic constituents. Although the infection constituents in the soybean pods caused pod mildew, they also helped mitigate the corresponding seed mildew to a certain extent.
2012-06-19
CAPE CANAVERAL, Fla. –Inside Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, a unique close-up view shows a large crane lowering the right orbital maneuvering system, or OMS, pod closer to space shuttle Atlantis and the left OMS pod already installed. It is the last time an OMS pod will be installed on Atlantis. The OMS provided the shuttle with thrust for orbit insertion, rendezvous and deorbit, and could provide up to 1,000 pounds of propellant to the aft reaction control system. The OMS is housed in two independent pods located on each side of the shuttle’s aft fuselage. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers. Atlantis’ OMS pods were removed and sent to the test facility at White Sands Space Harbor in New Mexico to be cleaned of residual toxic propellant. The work is part of the Space Shuttle Program’s transition and retirement processing of the space shuttle fleet. A groundbreaking was held Jan. 18 for Atlantis’ future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/transition. Photo credit: NASA/Dimitri Gerondidakis
2002-12-19
NASA Dryden's Automated Aerial Refueling (AAR) project evaluated the capability of an F/A-18A aircraft as an in-flight refueling tanker with the objective of developing analytical models for an automated aerial refueling system for unmanned air vehicles. The F/A-18 "tanker" aircraft (No. 847) underwent flight test envelope expansion with an aerodynamic pod containing air-refueling equipment carried beneath the fuselage. The second aircraft (No. 843) flew as the receiver aircraft during the study to assess the free-stream hose and drogue dynamics on the F/A-18A.
2002-12-19
NASA Dryden's Automated Aerial Refueling (AAR) project evaluated the capability of an F/A-18A aircraft as an in-flight refueling tanker with the objective of developing analytical models for an automated aerial refueling system for unmanned air vehicles. The F/A-18 "tanker" aircraft (No. 847) underwent flight test envelope expansion with an aerodynamic pod containing air-refueling equipment carried beneath the fuselage. The second aircraft (No. 843) flew as the receiver aircraft during the study to assess the free-stream hose and drogue dynamics on the F/A-18A.
2002-12-19
NASA Dryden's Automated Aerial Refueling (AAR) project evaluated the capability of an F/A-18A aircraft as an in-flight refueling tanker with the objective of developing analytical models for an automated aerial refueling system for unmanned air vehicles. The F/A-18 "tanker" aircraft (No. 847) underwent flight test envelope expansion with an aerodynamic pod containing air-refueling equipment carried beneath the fuselage. The second aircraft (No. 843) flew as the receiver aircraft during the study to assess the free-stream hose and drogue dynamics on the F/A-18A.
This NASA Dryden F/A-18 is participating in the Automated Aerial Refueling (AAR) project. F/A-18 (No
NASA Technical Reports Server (NTRS)
2002-01-01
A NASA Dryden F/A-18 is participating in the Automated Aerial Refueling (AAR) project. F/A-18 (No. 847) is acting as an in-flight refueling tanker in the study to develop analytical models for an automated aerial refueling system for unmanned vehicles. A 300-gallon aerodynamic pod containing air-refueling equipment is seen beneath the fuselage. The hose and refueling basket are extended during an assessment of their dynamics on the F/A-18A.
Boeing-747 aircraft with external cargo pod
NASA Technical Reports Server (NTRS)
Quartero, C. B.; Washburn, G. F.; Price, J. E.
1978-01-01
An analysis was conducted to investigate the feasibility of mounting a detachable pod to the underside of the fuselage of a Boeing Model 747 aircraft to carry outsized cargo in case of military emergency. The analysis showed that the 747 configured with the pod and carrying only a bridge launcher as payload attained a range of 8.70 Mm (4 700 n. mi.) at Mach .68. This range was based on a maximum take-off gross weight of 3.447 MN (775 000 1bf) which included 212 kN (47 700 lbf) pod weight and 543 kN (122 000 lbf) payload (bridge launcher).
ERIC Educational Resources Information Center
Bouck, Emily C.; Satsangi, Rajiv; Bartlett, Whitney; Weng, Pei-Lin
2012-01-01
In light of a positive research base regarding technology-based self-operating prompting systems (e.g., iPods), yet a concern about the sustainability of such technologies after a research project is completed, this study sought to explore the effectiveness and efficiency of an audio recorder, a low-cost, more commonly accessible technology to…
Palmer, Edward J; Devitt, Peter G
2007-01-01
Background Podcasting is currently a popular means of delivery of information with a large number of podcasts specifically tailored for educational purposes. It can be argued that the passive nature of this teaching methodology limits the educational benefit that can be derived from podcasts. This paper describes the development and construction of interactive material for the iPod, and a survey of student attitudes towards this type of learning material. Methods The development of interactive material for an iPod is described in detail. This material was developed and demonstrated to 50 medical students. These students completed a paper-based survey on the potential uses of this technology, before and after a 20 minute presentation in class of an interactive case-study on an iPod. Results A technical description of how to develop interactive content for the iPod was created. The results of the student survey indicate a favourable shift in student attitudes after viewing the interactive case. Despite only 15% of the students owning an iPod, 57% of the students were positive about having access to interactive iPod content and 59% believed they would use it whilst travelling. The percentage of students who felt podcasting was a useful means of learning increased from 9% to 41%. Conclusion The development of interactive content for the iPod is feasible. There are indications that students view interactive iPod cases as having value as an additional learning resource. PMID:17888168
Results from the EPL monkey-pod experiment conducted as part of the 1974 NASA/Ames shuttle CVT-2
NASA Technical Reports Server (NTRS)
Rahlmann, D. F.; Kodama, A. M.; Mains, R. C.; Pace, N.
1974-01-01
The participation of the Environmental Physiology Laboratory (EPL) in the general purpose laboratory concept verification test 3 is documented. The EPL Monkey-Pod Experiment was designed to incorporate a 10-12 kg, pig tailed monkey, Macaca nemestrina, into the pod and measure the physiological responses of the animal continuously. Four major elements comprise the EPL Monkey-Pod Experiment System: (1) a fiberglass pod containing the instrumented monkey plus feeder and watering devices, (2) an inner console containing the SKYLAB mass spectrometer with its associated valving and electronic controls, sensing, control and monitoring units for lower body negative pressure, feeder activity, waterer activity, temperatures, and gas metabolism calibration, (3) an umbilical complex comprising gas flow lines and electrical cabling between the inner and outer console and (4) an outer console in principle representing the experiment support to be provided from general spacecraft sources.
Results from the EPL monkey-pod flight experiments conducted aboard the NASA/Ames CV-990, May 1976
NASA Technical Reports Server (NTRS)
Rahlmann, D. F.; Kodama, A. M.; Mains, R. C.; Pace, N.
1976-01-01
The participation of the Environmental Physiology Laboratory (EPL) in the general purpose laboratory concept verification test 3 is documented. The EPL Monkey-Pod Experiment was designed to incorporate a 10-12 kg, pig tailed monkey, Macaca nemestrina, into the pod and measure the physiological responses of the animal continously. Four major elements comprise the EPL Monkey-Pod Experiment System: (1) a fiberglass pod containing the instrumented monkey plus feeder and watering devices, (2) an inner console containing the SKYLAB mass spectrometer with its associated valving and electronic controls, sensing, control and monitoring units for lower body negative pressure, feeder activity, waterer activity, temperatures, and gas metabolism calibration, (3) an umbilical complex comprising gas flow lines and electrical cabling between the inner and outer console and (4) an outer console in principle representing the experiment support to be provided from general space craft sources.
Precise orbit determination and rapid orbit recovery supported by time synchronization
NASA Astrophysics Data System (ADS)
Guo, Rui; Zhou, JianHua; Hu, XiaoGong; Liu, Li; Tang, Bo; Li, XiaoJie; Wu, Shan
2015-06-01
In order to maintain optimal signal coverage, GNSS satellites have to experience orbital maneuvers. For China's COMPASS system, precise orbit determination (POD) as well as rapid orbit recovery after maneuvers contribute to the overall Positioning, Navigation and Timing (PNT) service performance in terms of accuracy and availability. However, strong statistical correlations between clock offsets and the radial component of a satellite's positions require long data arcs for POD to converge. We propose here a new strategy which relies on time synchronization between ground tracking stations and in-orbit satellites. By fixing satellite clock offsets measured by the satellite station two-way synchronization (SSTS) systems and receiver clock offsets, POD and orbital recovery performance can be improved significantly. Using the Satellite Laser Ranging (SLR) as orbital accuracy evaluation, we find the 4-hr recovered orbit achieves about 0.71 m residual root mean square (RMS) error of fit SLR data, the recovery time is improved from 24-hr to 4-hr compared with the conventional POD without time synchronization support. In addition, SLR evaluation shows that for 1-hr prediction, about 1.47 m accuracy is achieved with the new proposed POD strategy.
NASA Astrophysics Data System (ADS)
Fen, Cao; XuHai, Yang; ZhiGang, Li; ChuGang, Feng
2016-08-01
The normal consecutive observing model in Chinese Area Positioning System (CAPS) can only supply observations of one GEO satellite in 1 day from one station. However, this can't satisfy the project need for observing many GEO satellites in 1 day. In order to obtain observations of several GEO satellites in 1 day like GPS/GLONASS/Galileo/BeiDou, the time-sharing observing model for GEO satellites in CAPS needs research. The principle of time-sharing observing model is illuminated with subsequent Precise Orbit Determination (POD) experiments using simulated time-sharing observations in 2005 and the real time-sharing observations in 2015. From time-sharing simulation experiments before 2014, the time-sharing observing 6 GEO satellites every 2 h has nearly the same orbit precision with the consecutive observing model. From POD experiments using the real time-sharing observations, POD precision for ZX12# and Yatai7# are about 3.234 m and 2.570 m, respectively, which indicates the time-sharing observing model is appropriate for CBTR system and can realize observing many GEO satellites in 1 day.
Hoekman, John D.; Ho, Rodney J.Y.
2011-01-01
Background Centrally acting opioid analgesics such as morphine and fentanyl are effective, but their efficacy is often limited by a delayed response or side effects resulting from systemic first-pass before reaching the brain and the central nervous system (CNS). It is generally accepted that drugs applied to the nasal cavity can directly access the brain and the CNS, which could provide therapeutic advantages such as rapid onset and lower systemic exposure. The olfactory region of the nasal cavity has been implicated in facilitating this direct nose-to-CNS transfer. If the fraction of opioid administered to the olfactory region could be improved, there could be a larger fraction of drug directly delivered to the CNS, mediating greater therapeutic benefit. Methods We have developed a pressurized olfactory delivery (POD) device to consistently and non-invasively deposit a majority of drug on the olfactory region of the nasal cavity in Sprague-Dawley rats. Using the tail-flick latency test and analysis of plasma and CNS tissue drug exposure, we compared distribution and efficacy of the opioids morphine and fentanyl administered to the nasal olfactory region with the POD device or the nasal respiratory region with nose drops or systemically via intraperitoneal (IP) injection. Results Compared to nose drop, POD administration of morphine resulted in significantly higher overall therapeutic effect (AUCeffect) without a significant increase in plasma drug exposure (AUCplasma). POD delivery of morphine resulted in a nose-to-CNS direct transport percentage of 38–55%. POD delivery of fentanyl led to a faster (5 min vs. 10 min) and more intense analgesic effect compared to nasal respiratory administration. Unlike IP injection or nose drop administration, both morphine and fentanyl given by the POD device to olfactory nasal epithelium exhibited clockwise [plasma] versus effect hysteresis after nasal POD administration, consistent with direct nose-to-CNS drug transport mechanism. Conclusions Deposition of opioids to the olfactory region within the nasal cavity could have a significant impact on drug distribution and pharmacodynamic effect, and thus should be considered into account in future nasally administered opioid studies. PMID:21709146
Deployable reconnaissance from a VTOL UAS in urban environments
NASA Astrophysics Data System (ADS)
Barnett, Shane; Bird, John; Culhane, Andrew; Sharkasi, Adam; Reinholtz, Charles
2007-04-01
Reconnaissance collection in unknown or hostile environments can be a dangerous and life threatening task. To reduce this risk, the Unmanned Systems Group at Virginia Tech has produced a fully autonomous reconnaissance system able to provide live video reconnaissance from outside and inside unknown structures. This system consists of an autonomous helicopter which launches a small reconnaissance pod inside a building and an operator control unit (OCU) on a ground station. The helicopter is a modified Bergen Industrial Twin using a Rotomotion flight controller and can fly missions of up to one half hour. The mission planning OCU can control the helicopter remotely through teleoperation or fully autonomously by GPS waypoints. A forward facing camera and template matching aid in navigation by identifying the target building. Once the target structure is identified, vision algorithms will center the UAS adjacent to open windows or doorways. Tunable parameters in the vision algorithm account for varying launch distances and opening sizes. Launch of the reconnaissance pod may be initiated remotely through a human in the loop or autonomously. Compressed air propels the half pound stationary pod or the larger mobile pod into the open portals. Once inside the building, the reconnaissance pod will then transmit live video back to the helicopter. The helicopter acts as a repeater node for increased video range and simplification of communication back to the ground station.
Reduced dynamical model of the vibrations of a metal plate
NASA Astrophysics Data System (ADS)
Moreno, D.; Barrientos, Bernardino; Perez-Lopez, Carlos; Mendoza-Santoyo, Fernando; Guerrero, J. A.; Funes, M.
2005-02-01
The Proper Orthogonal Decomposition (POD) method is applied to the vibrations analysis of a metal plate. The data obtained from the metal plate under vibrations were measured with a laser vibrometer. The metal plate was subject to vibrations with an electrodynamical shaker in a range of frequencies from 100 to 5000 Hz. The deformation measurements were taken on a quarter of the plate in a rectangular grid of 7 x 8 points. The plate deformation measurements were used to calculate the eigenfunctions and the eigenvalues. It was found that a large fraction of the total energy of the deformation is contained within the first six POD modes. The essential features of the deformation are thus described by only the six first eigenfunctions. A reduced order model for the dynamical behavior is then constructed using Galerkin projection of the equation of motion for the vertical displacement of a plate.
Yang, Sha; Li, Lin; Zhang, Jialei; Geng, Yun; Guo, Feng; Wang, Jianguo; Meng, Jingjing; Sui, Na; Wan, Shubo; Li, Xinguo
2017-01-01
Calcium not only serves as a necessary nutrient for plant growth but also acts as a ubiquitous central hub in a large number of signaling pathways. Free Ca2+ deficiency in the soil may cause early embryo abortion, which eventually led to abnormal development of peanut pod during the harvest season. To understand the mechanisms of Ca2+ regulation in pod development, transcriptome analysis of peanut gynophores and pods was performed by comparing the treatments between free Ca2+ sufficiency and free Ca2+ deficiency using Illumina HiSeq™ 2000. 9,903,082,800 nt bases are generated totally. After assembly, the average length of 102,819 unigenes is 999 nt, N50 is 1,782 nt. RNA-seq based gene expression profilings showed a large number of genes at the transcriptional level changed significantly between the aerial pegs and underground swelling pods under free Ca2+ sufficienct or deficiency treatments, respectively. Genes encoding key members of Ca2+ signaling transduction pathway, enzymes for hormone metabolism, cell division and growth, transcriptional factor as well as embryo development were highlighted. This information provides useful information for our further study. The results of digital gene expression (DGE) indicated that exogenous calcium might contribute to the development of peanut pod through its signal transduction pathway, meanwhile, promote the normal transition of the gynophores to the reproductive development. PMID:29033956
Multi-scale statistical analysis of coronal solar activity
Gamborino, Diana; del-Castillo-Negrete, Diego; Martinell, Julio J.
2016-07-08
Multi-filter images from the solar corona are used to obtain temperature maps that are analyzed using techniques based on proper orthogonal decomposition (POD) in order to extract dynamical and structural information at various scales. Exploring active regions before and after a solar flare and comparing them with quiet regions, we show that the multi-scale behavior presents distinct statistical properties for each case that can be used to characterize the level of activity in a region. Information about the nature of heat transport is also to be extracted from the analysis.
Intial orbit determination results for Jason-1: towards a 1-cm orbit
NASA Technical Reports Server (NTRS)
Haines, B. J.; Haines, B.; Bertiger, W.; Desai, S.; Kuang, D.; Munson, T.; Reichert, A.; Young, L.; Willis, P.
2002-01-01
The U.S/France Jason-1 oceanographic mission is carrying state-of-the-art radiometric tracking systems (GPS and Doris) to support precise orbit determination (POD) requirements. The performance of the systems is strongly reflected in the early POD results. Results of both internal and external (e.g., satellite laser ranging) comparisons support that the 2.5 cm radial Rh4S requirement is being readily met, and provide reasons for optimism that 1 cm can be achieved. We discuss the POD strategy underlying these orbits, as well as the challenging issues that bear on the understanding and characterization of an orbit solution at the l-cm level. We also describe a system for producing science quality orbits in near real time in order to support emerging applications in operational oceanography.
NASA Astrophysics Data System (ADS)
Taylor, Ron; Downey, Jack; Wood, Jeffrey; Lin, Yen-Hung; Bugata, Bharathi; Fan, Dongsheng; Hess, Carl; Wylie, Mark
2016-10-01
In this work, the SEMI specification for reticle and pod management (E109) with internal reticle library support has been integrated for the first time on KLA-Tencor's TeronTM and TeraScanTM reticle inspection tools. Manufacturing Execution System scheduling reticle jobs and Automated Material Handling System scheduling to transfer pods simultaneously have also been integrated and tested. GLOBALFOUNDRIES collaboratively worked with KLA-Tencor to successfully implement these capabilities. Both library and non-library scenarios have been demonstrated for comparison in a real production environment resulting in productivity increase of approximately 29% by making use of the library. Reticle re-qualification test cases were used for the comparison in this work.
Narayanan, K
2003-04-01
When nucleopolyhedro virus of A. atkinsoni was applied at 250 LE/ha, there was no significant difference between the viruses treated and control plots with regard to the total number of live larvae feeding outside the pod. However, due to changes in behaviour in NPV infected A. atkinsoni by way of coming out of the pod, there was a significant difference when counts were taken with regard to total number of larvae found feeding inside the pod. Both endosulfan at (0.07%) and virus (125 LE/ha) in combination with endosulfan (0.035%) significantly reduced the larval population of A. atkinsoni and Sphaenarches anisodactylus. There was no significant difference between the virus and control plots with regard to percentage of pod damage. However, when the yield was assessed based on the seed weight, there was significant difference.
Research on the impact factors of GRACE precise orbit determination by dynamic method
NASA Astrophysics Data System (ADS)
Guo, Nan-nan; Zhou, Xu-hua; Li, Kai; Wu, Bin
2018-07-01
With the successful use of GPS-only-based POD (precise orbit determination), more and more satellites carry onboard GPS receivers to support their orbit accuracy requirements. It provides continuous GPS observations in high precision, and becomes an indispensable way to obtain the orbit of LEO satellites. Precise orbit determination of LEO satellites plays an important role for the application of LEO satellites. Numerous factors should be considered in the POD processing. In this paper, several factors that impact precise orbit determination are analyzed, namely the satellite altitude, the time-variable earth's gravity field, the GPS satellite clock error and accelerometer observation. The GRACE satellites provide ideal platform to study the performance of factors for precise orbit determination using zero-difference GPS data. These factors are quantitatively analyzed on affecting the accuracy of dynamic orbit using GRACE observations from 2005 to 2011 by SHORDE software. The study indicates that: (1) with the altitude of the GRACE satellite is lowered from 480 km to 460 km in seven years, the 3D (three-dimension) position accuracy of GRACE satellite orbit is about 3˜4 cm based on long spans data; (2) the accelerometer data improves the 3D position accuracy of GRACE in about 1 cm; (3) the accuracy of zero-difference dynamic orbit is about 6 cm with the GPS satellite clock error products in 5 min sampling interval and can be raised to 4 cm, if the GPS satellite clock error products with 30 s sampling interval can be adopted. (4) the time-variable part of earth gravity field model improves the 3D position accuracy of GRACE in about 0.5˜1.5 cm. Based on this study, we quantitatively analyze the factors that affect precise orbit determination of LEO satellites. This study plays an important role to improve the accuracy of LEO satellites orbit determination.
Molecular basis of a shattering resistance boosting global dissemination of soybean
Funatsuki, Hideyuki; Suzuki, Masaya; Hirose, Aya; Inaba, Hiroki; Yamada, Tetsuya; Hajika, Makita; Komatsu, Kunihiko; Katayama, Takeshi; Sayama, Takashi; Ishimoto, Masao; Fujino, Kaien
2014-01-01
Pod dehiscence (shattering) is essential for the propagation of wild plant species bearing seeds in pods but is a major cause of yield loss in legume and crucifer crops. Although natural genetic variation in pod dehiscence has been, and will be, useful for plant breeding, little is known about the molecular genetic basis of shattering resistance in crops. Therefore, we performed map-based cloning to unveil a major quantitative trait locus (QTL) controlling pod dehiscence in soybean. Fine mapping and complementation testing revealed that the QTL encodes a dirigent-like protein, designated as Pdh1. The gene for the shattering-resistant genotype, pdh1, was defective, having a premature stop codon. The functional gene, Pdh1, was highly expressed in the lignin-rich inner sclerenchyma of pod walls, especially at the stage of initiation in lignin deposition. Comparisons of near-isogenic lines indicated that Pdh1 promotes pod dehiscence by increasing the torsion of dried pod walls, which serves as a driving force for pod dehiscence under low humidity. A survey of soybean germplasm revealed that pdh1 was frequently detected in landraces from semiarid regions and has been extensively used for breeding in North America, the world’s leading soybean producer. These findings point to a new mechanism for pod dehiscence involving the dirigent protein family and suggest that pdh1 has played a crucial role in the global expansion of soybean cultivation. Furthermore, the orthologs of pdh1, or genes with the same role, will possibly be useful for crop improvement. PMID:25468966
Sánchez-Segado, S; Lozano, L J; de Los Ríos, A P; Hernández-Fernández, F J; Godínez, C; Juan, D
2012-01-01
A process for the production of ethanol from carob (Ceratonia siliqua) pods was designed and an economic analysis was carried out for a hypothetical plant. The plant was assumed to perform an aqueous extraction of sugars from the pods followed by fermentation and distillation to produce ethanol. The total fixed capital investment for a base case process with a capacity to transform 68,000 t/year carob pod was calculated as 39.61 millon euros (€) with a minimum bioethanol production cost of 0.51 €/L and an internal rate of return of 7%. The plant was found to be profitable at carob pod prices lower than 0.188 €/kg. An increase in the transformation capacity of the plant from 33,880 to 135,450 t/year was calculated to result in an increase in the internal rate of return from 5.50% to 13.61%. The obtained results show that carob pod is a promising alternative source for bioethanol production. Copyright © 2011 Elsevier Ltd. All rights reserved.
Glow phenomenon surrounding the vertical stabilizer and OMS pods
1994-03-05
STS062-42-026 (4-18 March 1994) --- This 35mm frame, photographed as the Space Shuttle Columbia was orbiting Earth during a "night" pass, documents the glow phenomenon surrounding the vertical stabilizer and the Orbital Maneuvering System (OMS) pods of the spacecraft.
Krahn, Margaret M; Hanson, M Bradley; Schorr, Gregory S; Emmons, Candice K; Burrows, Douglas G; Bolton, Jennie L; Baird, Robin W; Ylitalo, Gina M
2009-10-01
"Southern Resident" killer whales (Orcinus orca) that comprise three fish-eating "pods" (J, K and L) were listed as "endangered" in the US and Canada following a 20% population decline between 1996 and 2001. Blubber biopsy samples from Southern Resident juveniles had statistically higher concentrations of certain persistent organic pollutants than were found for adults. Most Southern Resident killer whales, including the four juveniles, exceeded the health-effects threshold for total PCBs in marine mammal blubber. Maternal transfer of contaminants to the juveniles during rapid development of their biological systems may put these young whales at greater risk than adults for adverse health effects (e.g., immune and endocrine system dysfunction). Pollutant ratios and field observations established that two of the pods (K- and L-pod) travel to California to forage. Nitrogen stable isotope values, supported by field observations, indicated possible changes in the diet of L-pod over the last decade.
NASA Technical Reports Server (NTRS)
Anglim, D. D.; Bruns, A. E.; Perryman, D. C.; Wieland, D. L.
1972-01-01
Auxiliary propulsion concepts for application to the space shuttle are compared. Both monopropellant and bipropellant earth storable reaction control systems were evaluated. The fundamental concepts evaluated were: (1) monopropellant and bipropellant systems installed integrally within the vehicle, (2) fuel systems installed modularly in nose and wing tip pods, and (3) fuel systems installed modularly in nose and fuselage pods. Numerous design variations within these three concepts were evaluated. The system design analysis and methods for implementing each of the concepts are reported.
A Signal-to-Noise Crossover Dose as the Point of Departure for Health Risk Assessment
Portier, Christopher J.; Krewski, Daniel
2011-01-01
Background: The U.S. National Toxicology Program (NTP) cancer bioassay database provides an opportunity to compare both existing and new approaches to determining points of departure (PoDs) for establishing reference doses (RfDs). Objectives: The aims of this study were a) to investigate the risk associated with the traditional PoD used in human health risk assessment [the no observed adverse effect level (NOAEL)]; b) to present a new approach based on the signal-to-noise crossover dose (SNCD); and c) to compare the SNCD and SNCD-based RfD with PoDs and RfDs based on the NOAEL and benchmark dose (BMD) approaches. Methods: The complete NTP database was used as the basis for these analyses, which were performed using the Hill model. We determined NOAELs and estimated corresponding extra risks. Lower 95% confidence bounds on the BMD (BMDLs) corresponding to extra risks of 1%, 5%, and 10% (BMDL01, BMDL05, and BMDL10, respectively) were also estimated. We introduce the SNCD as a new PoD, defined as the dose where the additional risk is equal to the “background noise” (the difference between the upper and lower bounds of the two-sided 90% confidence interval on absolute risk) or a specified fraction thereof. Results: The median risk at the NOAEL was approximately 10%, and the default uncertainty factor (UF = 100) was considered most applicable to the BMDL10. Therefore, we chose a target risk of 1/1,000 (0.1/100) to derive an SNCD-based RfD by linear extrapolation. At the median, this approach provided the same RfD as the BMDL10 divided by the default UF. Conclusions: Under a standard BMD approach, the BMDL10 is considered to be the most appropriate PoD. The SNCD approach, which is based on the lowest dose at which the signal can be reliably detected, warrants further development as a PoD for human health risk assessment. PMID:21813365
Maier, A; Vincent, M; Hack, E; Nance, P; Ball, W
2014-04-01
Inorganic borates are encountered in many settings worldwide, spurring international efforts to develop exposure guidance (US EPA, 2004; WHO, 2009; ATSDR, 2010) and occupational exposure limits (OEL) (ACGIH, 2005; MAK, 2011). We derived an updated OEL to reflect new data and current international risk assessment frameworks. We assessed toxicity and epidemiology data on inorganic borates to identify relevant adverse effects. International risk assessment frameworks (IPCS, 2005, 2007) were used to evaluate endpoint candidates: reproductive toxicity, developmental toxicity, and sensory irritation. For each endpoint, a preliminary OEL was derived and adjusted based on consideration of toxicokinetics, toxicodynamics, and other uncertainties. Selection of the endpoint point of departures (PODs) is supported by dose-response modeling. Developmental toxicity was the most sensitive systemic effect. An OEL of 1.6mgB/m(3) was estimated for this effect based on a POD of 63mgB/m(3) with an uncertainty factor (UF) of 40. Sensory irritation was considered to be the most sensitive effect for the portal of entry. An OEL of 1.4mgB/m(3) was estimated for this effect based on the identified POD and an UF of 1. An OEL of 1.4mgB/m(3) as an 8-h time-weighted average (TWA) is recommended. Copyright © 2014 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Sadighi, Kira; Coffey, Evan; Polidori, Andrea; Feenstra, Brandon; Lv, Qin; Henze, Daven K.; Hannigan, Michael
2018-03-01
Sensor networks are being more widely used to characterize and understand compounds in the atmosphere like ozone (O3). This study employs a measurement tool, called the U-Pod, constructed at the University of Colorado Boulder, to investigate spatial and temporal variability of O3 in a 200 km2 area of Riverside County near Los Angeles, California. This tool contains low-cost sensors to collect ambient data at non-permanent locations. The U-Pods were calibrated using a pre-deployment field calibration technique; all the U-Pods were collocated with regulatory monitors. After collocation, the U-Pods were deployed in the area mentioned. A subset of pods was deployed at two local regulatory air quality monitoring stations providing validation for the collocation calibration method. Field validation of sensor O3 measurements to minute-resolution reference observations resulted in R2 and root mean squared errors (RMSEs) of 0.95-0.97 and 4.4-5.9 ppbv, respectively. Using the deployment data, ozone concentrations were observed to vary on this small spatial scale. In the analysis based on hourly binned data, the median R2 values between all possible U-Pod pairs varied from 0.52 to 0.86 for ozone during the deployment. The medians of absolute differences were calculated between all possible pod pairs, 21 pairs total. The median values of those median absolute differences for each hour of the day varied between 2.2 and 9.3 ppbv for the ozone deployment. Since median differences between U-Pod concentrations during deployment are larger than the respective root mean square error values, we can conclude that there is spatial variability in this criteria pollutant across the study area. This is important because it means that citizens may be exposed to more, or less, ozone than they would assume based on current regulatory monitoring.
Feedback stabilization of an oscillating vertical cylinder by POD Reduced-Order Model
NASA Astrophysics Data System (ADS)
Tissot, Gilles; Cordier, Laurent; Noack, Bernd R.
2015-01-01
The objective is to demonstrate the use of reduced-order models (ROM) based on proper orthogonal decomposition (POD) to stabilize the flow over a vertically oscillating circular cylinder in the laminar regime (Reynolds number equal to 60). The 2D Navier-Stokes equations are first solved with a finite element method, in which the moving cylinder is introduced via an ALE method. Since in fluid-structure interaction, the POD algorithm cannot be applied directly, we implemented the fictitious domain method of Glowinski et al. [1] where the solid domain is treated as a fluid undergoing an additional constraint. The POD-ROM is classically obtained by projecting the Navier-Stokes equations onto the first POD modes. At this level, the cylinder displacement is enforced in the POD-ROM through the introduction of Lagrange multipliers. For determining the optimal vertical velocity of the cylinder, a linear quadratic regulator framework is employed. After linearization of the POD-ROM around the steady flow state, the optimal linear feedback gain is obtained as solution of a generalized algebraic Riccati equation. Finally, when the optimal feedback control is applied, it is shown that the flow converges rapidly to the steady state. In addition, a vanishing control is obtained proving the efficiency of the control approach.
Polarity-defective mutants of Aspergillus nidulans.
Osherov, N; Mathew, J; May, G S
2000-12-01
We have identified two polarity-defective (pod) mutants in Aspergillus nidulans from a collection of heat-sensitive lethal mutants. At restrictive temperature, these mutants are capable of nuclear division but are unable to establish polar hyphal growth. We cloned the two pod genes by complementation of their heat-sensitive lethal phenotypes. The libraries used to clone the pod genes are under the control of the bidirectional niaD and niiA promoters. Complementation of the pod mutants is dependent on growth on inducing medium. We show that rescue of the heat-sensitive phenotype on inducing media is independent of the orientation of the gene relative to the niaD or niiA promoters, demonstrating that the intergenic region between the niaD and the niiA genes functions as an orientation-independent enhancer and repressor that is capable of functioning over long distances. The products of the podG and the podH genes were identified as homologues of the alpha subunit of yeast mitochondrial phenylalanyl--tRNA synthetase and transcription factor IIF interacting component of the CTD phosphatase. Neither of these gene products would have been predicted to produce a pod mutant phenotype based on studies of cellular polarity mutants in other organisms. The implications of these results are discussed. Copyright 2000 Academic Press.
A view of the Columbia's OMS engine pods during a burn
2013-11-18
STS093-347-031 (22-27 July 1999) --- Black space forms the backdrop for this scene of the Orbital Maneuvering System (OMS) engine pods during a thruster burn photographed by one of the astronauts on the aft flight deck of the Space Shuttle Columbia.
ERIC Educational Resources Information Center
van der Meer, Larah; Kagohara, Debora; Achmadi, Donna; Green, Vanessa A.; Herrington, Christina; Sigafoos, Jeff; O'Reilly, Mark F.; Lancioni, Giulio E.; Lang, Russell; Rispoli, Mandy
2011-01-01
Anecdotal reports suggest that individuals with developmental disabilities who lack speech may be enabled to communicate through the use of a new iPod-based communication device. However, there appear to be limited empirical data demonstrating successful use of this new device by such individuals. This study was designed to provide empirical…
ERIC Educational Resources Information Center
Achmadi, Donna; Kagohara, Debora M.; van der Meer, Larah; O'Reilly, Mark F.; Lancioni, Giulio E.; Sutherland, Dean; Lang, Russell; Marschik, Peter B.; Green, Vanessa A.; Sigafoos, Jeff
2012-01-01
We evaluated a program for teaching two adolescents with autism spectrum disorders (ASD) to perform more advanced operations on an iPod-based speech-generating device (SGD). The effects of the teaching program were evaluated in a multiprobe multiple baseline across participants design that included two intervention phases. The first intervention…
ERIC Educational Resources Information Center
Strasberger, Sean
2013-01-01
Non-verbal children with autism are candidates for augmentative and alternative communication (AAC). One type of AAC device is a voice output communication aid (VOCA). The primary drawbacks of past VOCAs were their expense and portability. Newer iPod-based VOCAs alleviate these concerns. This dissertation sought to extend the iPod-based VOCA…
SCHULTZ, ELISE V.; SCHULTZ, CHRISTOPHER J.; CAREY, LAWRENCE D.; CECIL, DANIEL J.; BATEMAN, MONTE
2017-01-01
This study develops a fully automated lightning jump system encompassing objective storm tracking, Geostationary Lightning Mapper proxy data, and the lightning jump algorithm (LJA), which are important elements in the transition of the LJA concept from a research to an operational based algorithm. Storm cluster tracking is based on a product created from the combination of a radar parameter (vertically integrated liquid, VIL), and lightning information (flash rate density). Evaluations showed that the spatial scale of tracked features or storm clusters had a large impact on the lightning jump system performance, where increasing spatial scale size resulted in decreased dynamic range of the system’s performance. This framework will also serve as a means to refine the LJA itself to enhance its operational applicability. Parameters within the system are isolated and the system’s performance is evaluated with adjustments to parameter sensitivity. The system’s performance is evaluated using the probability of detection (POD) and false alarm ratio (FAR) statistics. Of the algorithm parameters tested, sigma-level (metric of lightning jump strength) and flash rate threshold influenced the system’s performance the most. Finally, verification methodologies are investigated. It is discovered that minor changes in verification methodology can dramatically impact the evaluation of the lightning jump system. PMID:29303164
Feng, Zhaozhong; Calatayud, Vicent; Zhu, Jianguo; Kobayashi, Kazuhiko
2018-04-01
Five winter wheat cultivars were exposed to ambient (A-O 3 ) and elevated (E-O 3 , 1.5 ambient) O 3 in a fully open-air fumigation system in China. Ozone exposure- and flux based response relationships were established for seven physiological variables related to photosynthesis. The performance of the fitting of the regressions in terms of R 2 increased when second order regressions instead of first order ones were used, suggesting that effects of O 3 were more pronounced towards the last developmental stages of the wheat. The more robust indicators were those related with CO 2 assimilation, Rubisco activity and RuBP regeneration capacity (A sat , J max and Vc max ), and chlorophyll content (Chl). Flux-based metrics (POD y , Phytotoxic O 3 Dose over a threshold ynmolO 3 m -2 s -1 ) predicted slightly better the responses to O 3 than exposure metrics (AOTX, Accumulated O 3 exposure over an hourly Threshold of X ppb) for most of the variables. The best performance was observed for metrics POD 1 ( A sat , J max and Vc max ) and POD 3 (Chl). For this crop, the proposed response functions could be used for O 3 risk assessment based on physiological effects and also to include the influence of O 3 on yield or other variables in models with a photosynthetic component. Copyright © 2017 Elsevier B.V. All rights reserved.
2012-06-19
CAPE CANAVERAL, Fla. – Inside Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, a large crane moves the right orbital maneuvering system, or OMS, pod closer to space shuttle Atlantis. It is the last time an OMS pod will be installed on Atlantis. The OMS provided the shuttle with thrust for orbit insertion, rendezvous and deorbit, and could provide up to 1,000 pounds of propellant to the aft reaction control system. The OMS is housed in two independent pods located on each side of the shuttle’s aft fuselage. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers. Atlantis’ OMS pods were removed and sent to the test facility at White Sands Space Harbor in New Mexico to be cleaned of residual toxic propellant. The work is part of the Space Shuttle Program’s transition and retirement processing of the space shuttle fleet. A groundbreaking was held Jan. 18 for Atlantis’ future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/transition. Photo credit: NASA/Dimitri Gerondidakis
2012-06-19
CAPE CANAVERAL, Fla. – Inside Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, a large crane moves the right orbital maneuvering system, or OMS, pod closer to space shuttle Atlantis. It is the last time an OMS pod will be installed on Atlantis. The OMS provided the shuttle with thrust for orbit insertion, rendezvous and deorbit, and could provide up to 1,000 pounds of propellant to the aft reaction control system. The OMS is housed in two independent pods located on each side of the shuttle’s aft fuselage. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers. Atlantis’ OMS pods were removed and sent to the test facility at White Sands Space Harbor in New Mexico to be cleaned of residual toxic propellant. The work is part of the Space Shuttle Program’s transition and retirement processing of the space shuttle fleet. A groundbreaking was held Jan. 18 for Atlantis’ future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/transition. Photo credit: NASA/Dimitri Gerondidakis
2012-06-19
CAPE CANAVERAL, Fla. – Inside Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, a large crane moves the right orbital maneuvering system, or OMS, pod closer to space shuttle Atlantis. It is the last time an OMS pod will be installed on Atlantis. The OMS provided the shuttle with thrust for orbit insertion, rendezvous and deorbit, and could provide up to 1,000 pounds of propellant to the aft reaction control system. The OMS is housed in two independent pods located on each side of the shuttle’s aft fuselage. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers. Atlantis’ OMS pods were removed and sent to the test facility at White Sands Space Harbor in New Mexico to be cleaned of residual toxic propellant. The work is part of the Space Shuttle Program’s transition and retirement processing of the space shuttle fleet. A groundbreaking was held Jan. 18 for Atlantis’ future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/transition. Photo credit: NASA/Dimitri Gerondidakis
2012-06-19
CAPE CANAVERAL, Fla. – Inside Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, a large crane lowers the right orbital maneuvering system, or OMS, pod closer to space shuttle Atlantis. It is the last time an OMS pod will be installed on Atlantis. The OMS provided the shuttle with thrust for orbit insertion, rendezvous and deorbit, and could provide up to 1,000 pounds of propellant to the aft reaction control system. The OMS is housed in two independent pods located on each side of the shuttle’s aft fuselage. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers. Atlantis’ OMS pods were removed and sent to the test facility at White Sands Space Harbor in New Mexico to be cleaned of residual toxic propellant. The work is part of the Space Shuttle Program’s transition and retirement processing of the space shuttle fleet. A groundbreaking was held Jan. 18 for Atlantis’ future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/transition. Photo credit: NASA/Dimitri Gerondidakis
2012-06-19
CAPE CANAVERAL, Fla. – Inside Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, a large crane lowers the right orbital maneuvering system, or OMS, pod onto space shuttle Atlantis. It is the last time an OMS pod will be installed on Atlantis. The OMS provided the shuttle with thrust for orbit insertion, rendezvous and deorbit, and could provide up to 1,000 pounds of propellant to the aft reaction control system. The OMS is housed in two independent pods located on each side of the shuttle’s aft fuselage. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers. Atlantis’ OMS pods were removed and sent to the test facility at White Sands Space Harbor in New Mexico to be cleaned of residual toxic propellant. The work is part of the Space Shuttle Program’s transition and retirement processing of the space shuttle fleet. A groundbreaking was held Jan. 18 for Atlantis’ future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/transition. Photo credit: NASA/Dimitri Gerondidakis
2012-06-19
CAPE CANAVERAL, Fla. – Inside Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, preparations are underway to install the right orbital maneuvering system, or OMS, pod on space shuttle Atlantis. It will be the last time an OMS pod is installed on Atlantis. The OMS provided the shuttle with thrust for orbit insertion, rendezvous and deorbit, and could provide up to 1,000 pounds of propellant to the aft reaction control system. The OMS is housed in two independent pods located on each side of the shuttle’s aft fuselage. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers. Atlantis’ OMS pods were removed and sent to the test facility at White Sands Space Harbor in New Mexico to be cleaned of residual toxic propellant. The work is part of the Space Shuttle Program’s transition and retirement processing of the space shuttle fleet. A groundbreaking was held Jan. 18 for Atlantis’ future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/transition. Photo credit: NASA/Dimitri Gerondidakis
The next generation of low-cost personal air quality sensors for quantitative exposure monitoring
NASA Astrophysics Data System (ADS)
Piedrahita, R.; Xiang, Y.; Masson, N.; Ortega, J.; Collier, A.; Jiang, Y.; Li, K.; Dick, R. P.; Lv, Q.; Hannigan, M.; Shang, L.
2014-10-01
Advances in embedded systems and low-cost gas sensors are enabling a new wave of low-cost air quality monitoring tools. Our team has been engaged in the development of low-cost, wearable, air quality monitors (M-Pods) using the Arduino platform. These M-Pods house two types of sensors - commercially available metal oxide semiconductor (MOx) sensors used to measure CO, O3, NO2, and total VOCs, and NDIR sensors used to measure CO2. The MOx sensors are low in cost and show high sensitivity near ambient levels; however they display non-linear output signals and have cross-sensitivity effects. Thus, a quantification system was developed to convert the MOx sensor signals into concentrations. We conducted two types of validation studies - first, deployments at a regulatory monitoring station in Denver, Colorado, and second, a user study. In the two deployments (at the regulatory monitoring station), M-Pod concentrations were determined using collocation calibrations and laboratory calibration techniques. M-Pods were placed near regulatory monitors to derive calibration function coefficients using the regulatory monitors as the standard. The form of the calibration function was derived based on laboratory experiments. We discuss various techniques used to estimate measurement uncertainties. The deployments revealed that collocation calibrations provide more accurate concentration estimates than laboratory calibrations. During collocation calibrations, median standard errors ranged between 4.0-6.1 ppb for O3, 6.4-8.4 ppb for NO2, 0.28-0.44 ppm for CO, and 16.8 ppm for CO2. Median signal to noise (S / N) ratios for the M-Pod sensors were higher than the regulatory instruments: for NO2, 3.6 compared to 23.4; for O3, 1.4 compared to 1.6; for CO, 1.1 compared to 10.0; and for CO2, 42.2 compared to 300-500. By contrast, lab calibrations added bias and made it difficult to cover the necessary range of environmental conditions to obtain a good calibration. A separate user study was also conducted to assess uncertainty estimates and sensor variability. In this study, 9 M-Pods were calibrated via collocation multiple times over 4 weeks, and sensor drift was analyzed, with the result being a calibration function that included baseline drift. Three pairs of M-Pods were deployed, while users individually carried the other three. The user study suggested that inter-M-Pod variability between paired units was on the same order as calibration uncertainty; however, it is difficult to make conclusions about the actual personal exposure levels due to the level of user engagement. The user study provided real-world sensor drift data, showing limited CO drift (under -0.05 ppm day-1), and higher for O3 (-2.6 to 2.0 ppb day-1), NO2 (-1.56 to 0.51 ppb day-1), and CO2 (-4.2 to 3.1 ppm day-1). Overall, the user study confirmed the utility of the M-Pod as a low-cost tool to assess personal exposure.
Cacao pod husks as a source of low-methoxyl, highly acetylated pectins able to gel in acidic media.
Vriesmann, Lúcia Cristina; de Oliveira Petkowicz, Carmen Lúcia
2017-08-01
Cacao pod husks, the main by-product from cocoa production, have been investigated for pectin isolation. In the present study, the rheological properties of two low-methoxyl (LM) pectins isolated from cacao pod husks using different extraction conditions were evaluated. One pectin was obtained from optimized conditions employing aqueous nitric acid as an extractant, and the other one was extracted with boiling water. Pectin gels (0.99% galacturonic acid equivalent, w/w) were prepared at pH 2.5-3.0 in the presence of 60% sucrose (w/w) and subjected to rheological analysis. Dynamic oscillatory experiments at 25°C indicated that better gels were obtained at the lowest pH (2.5). Steady shear measurements revealed a shear-thinning behavior. The apparent viscosities of the samples increased as pH decreased. Gelation with calcium ions was not observed for either of the highly acetylated LM pectins analyzed. The rheological analysis results showed that despite their high acetyl content, LM pectins extracted by different methods from cacao pod husks were able to form gels at low pH under reduced water activity, suggesting a possible application in acidic products. Copyright © 2017 Elsevier B.V. All rights reserved.
Coherent resonance stop bands in alternating gradient beam transport
NASA Astrophysics Data System (ADS)
Ito, K.; Okamoto, H.; Tokashiki, Y.; Fukushima, K.
2017-06-01
An extensive experimental study is performed to confirm fundamental resonance bands of an intense hadron beam propagating through an alternating gradient linear transport channel. The present work focuses on the most common lattice geometry called "FODO" or "doublet" that consists of two quadrupoles of opposite polarities. The tabletop ion-trap system "S-POD" (Simulator of Particle Orbit Dynamics) developed at Hiroshima University is employed to clarify the parameter-dependence of coherent beam instability. S-POD can provide a non-neutral plasma physically equivalent to a charged-particle beam in a periodic focusing potential. In contrast with conventional experimental approaches relying on large-scale machines, it is straightforward in S-POD to control the doublet geometry characterized by the quadrupole filling factor and drift-space ratio. We verify that the resonance feature does not essentially change depending on these geometric factors. A few clear stop bands of low-order resonances always appear in the same pattern as previously found with the sinusoidal focusing model. All stop bands become widened and shift to the higher-tune side as the beam density is increased. In the space-charge-dominated regime, the most dangerous stop band is located at the bare betatron phase advance slightly above 90 degrees. Experimental data from S-POD suggest that this severe resonance is driven mainly by the linear self-field potential rather than by nonlinear external imperfections and, therefore, unavoidable at high beam density. The instability of the third-order coherent mode generates relatively weak but noticeable stop bands near the phase advances of 60 and 120 degrees. The latter sextupole stop band is considerably enhanced by lattice imperfections. In a strongly asymmetric focusing channel, extra attention may have to be paid to some coupling resonance lines induced by the Coulomb potential. Our interpretations of experimental data are supported by theoretical predictions and systematic multiparticle simulations.
Variability within Systemic In Vivo Toxicity Points-of-Departure (SOT)
In vivo studies have long been considered the gold standard for toxicology screening and deriving points of departure (POD). With the push to decrease the use of animal studies, predictive models using in vivo data are being developed to estimate POD. However, recent work has il...
Raman, Rosy; Qiu, Yu; Coombes, Neil; Song, Jie; Kilian, Andrzej; Raman, Harsh
2017-01-01
Seed lost due to easy pod dehiscence at maturity (pod shatter) is a major problem in several members of Brassicaceae family. We investigated the level of pod shatter resistance in Ethiopian mustard (Brassica carinata) and identified quantitative trait loci (QTL) for targeted introgression of this trait in Ethiopian mustard and its close relatives of the genus Brassica. A set of 83 accessions of B. carinata, collected from the Australian Grains Genebank, was evaluated for pod shatter resistance based on pod rupture energy (RE). In comparison to B. napus (RE = 2.16 mJ), B. carinata accessions had higher RE values (2.53 to 20.82 mJ). A genetic linkage map of an F2 population from two contrasting B. carinata selections, BC73526 (shatter resistant with high RE) and BC73524 (shatter prone with low RE) comprising 300 individuals, was constructed using a set of 6,464 high quality DArTseq markers and subsequently used for QTL analysis. Genetic analysis of the F2 and F2:3 derived lines revealed five statistically significant QTL (LOD ≥ 3) that are linked with pod shatter resistance on chromosomes B1, B3, B8, and C5. Herein, we report for the first time, identification of genetic loci associated with pod shatter resistance in B. carinata. These characterized accessions would be useful in Brassica breeding programs for introgression of pod shatter resistance alleles in to elite breeding lines. Molecular markers would assist marker-assisted selection for tracing the introgression of resistant alleles. Our results suggest that the value of the germplasm collections can be harnessed through genetic and genomics tools. PMID:29250080
DOE Office of Scientific and Technical Information (OSTI.GOV)
Beiser, L.; Veligdan, J.
A Planar Optic Display (POD) is being built and tested for suitability as a high brightness replacement for the cathode ray tube, (CRT). The POD display technology utilizes a laminated optical waveguide structure which allows a projection type of display to be constructed in a thin (I to 2 inch) housing. Inherent in the optical waveguide is a black cladding matrix which gives the display a black appearance leading to very high contrast. A Digital Micromirror Device, (DMD) from Texas Instruments is used to create video images in conjunction with a 100 milliwatt green solid state laser. An anamorphic opticalmore » system is used to inject light into the POD to form a stigmatic image. In addition to the design of the POD screen, we discuss: image formation, image projection, and optical design constraints.« less
ERIC Educational Resources Information Center
Stav, John; Nielsen, Kjetil; Hansen-Nygard, Gabrielle; Thorseth, Trond
2010-01-01
A new type of Student Response System (SRS) based up on the latest wireless technologies and hand held mobile devices has been developed to enhance active learning methods and assess students' understanding. The key services involve a set of XML technologies, web services and modern mobile devices. A group consisting of engineers, scientists and…
Improving succinic acid production by Actinobacillus succinogenes from raw industrial carob pods.
Carvalho, Margarida; Roca, Christophe; Reis, Maria A M
2016-10-01
Carob pods are an inexpensive by-product of locust bean gum industry that can be used as renewable feedstock for bio-based succinic acid. Here, for the first time, unprocessed raw carob pods were used to extract a highly enriched sugar solution, afterwards used as substrate to produce succinic acid using Actinobacillus succinogenes. Batch fermentations containing 30g/L sugars resulted in a production rate of 1.67gSA/L.h and a yield of 0.39gSA/g sugars. Taking advantage of A. succinogenes' metabolism, uncoupling cell growth from succinic acid production, a fed-batch mode was implemented to increase succinic acid yield and reduce by-products formation. This strategy resulted in a succinic acid yield of 0.94gSA/g sugars, the highest yield reported in the literature for fed-batch and continuous experiments, while maintaining by-products at residual values. Results demonstrate that raw carob pods are a highly efficient feedstock for bio-based succinic acid production. Copyright © 2016 Elsevier Ltd. All rights reserved.
Reliable Alignment in Total Knee Arthroplasty by the Use of an iPod-Based Navigation System
Koenen, Paola; Schneider, Marco M.; Fröhlich, Matthias; Driessen, Arne; Bouillon, Bertil; Bäthis, Holger
2016-01-01
Axial alignment is one of the main objectives in total knee arthroplasty (TKA). Computer-assisted surgery (CAS) is more accurate regarding limb alignment reconstruction compared to the conventional technique. The aim of this study was to analyse the precision of the innovative navigation system DASH® by Brainlab and to evaluate the reliability of intraoperatively acquired data. A retrospective analysis of 40 patients was performed, who underwent CAS TKA using the iPod-based navigation system DASH. Pre- and postoperative axial alignment were measured on standardized radiographs by two independent observers. These data were compared with the navigation data. Furthermore, interobserver reliability was measured. The duration of surgery was monitored. The mean difference between the preoperative mechanical axis by X-ray and the first intraoperatively measured limb axis by the navigation system was 2.4°. The postoperative X-rays showed a mean difference of 1.3° compared to the final navigation measurement. According to radiographic measurements, 88% of arthroplasties had a postoperative limb axis within ±3°. The mean additional time needed for navigation was 5 minutes. We could prove very good precision for the DASH system, which is comparable to established navigation devices with only negligible expenditure of time compared to conventional TKA. PMID:27313898
Pediatric exposure to laundry detergent pods.
Valdez, Amanda L; Casavant, Marcel J; Spiller, Henry A; Chounthirath, Thiphalak; Xiang, Huiyun; Smith, Gary A
2014-12-01
Laundry detergent pods are a new product in the US marketplace. This study investigates the epidemiologic characteristics and outcomes of laundry detergent pod exposures among young children in the United States. Using data from the National Poison Data System, exposures to laundry detergent pods among children younger than 6 years of age during 2012-2013 were investigated. There were 17 230 children younger than 6 years exposed to laundry detergent pods in 2012-2013. From March 2012 to April 2013, the monthly number of exposures increased by 645.3%, followed by a 25.1% decrease from April to December 2013. Children younger than 3 years accounted for 73.5% of cases. The major route of exposure was ingestion, accounting for 79.7% of cases. Among exposed children, 4.4% were hospitalized and 7.5% experienced a moderate or major medical outcome. A spectrum of clinical effects from minor to serious was seen with ingestion and ocular exposures. There were 102 patients (0.6%) exposed to a detergent pod via ingestion, aspiration, or a combination of routes, including ingestion, who required tracheal intubation. There was 1 confirmed death. Laundry detergent pods pose a serious poisoning risk to young children. This nationwide study underscores the need for increased efforts to prevent exposure of young children to these products, which may include improvements in product packaging and labeling, development of a voluntary product safety standard, and public education. Product constituent reformulation is another potential strategy to mitigate the severity of clinical effects of laundry detergent pod exposure. Copyright © 2014 by the American Academy of Pediatrics.
Closeup view of the aft fuselage of the Orbiter Discovery ...
Close-up view of the aft fuselage of the Orbiter Discovery on the starboard side looking forward. This view is of the attach surface for the Orbiter Maneuvering System/Reaction Control System (OMS/RCS) Pod. The OMS/RCS pods are removed for processing and reconditioning at another facility. This view was taken from a service platform in the Orbiter Processing Facility at Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX
2004-04-21
KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, the left-hand Orbital Maneuvering System (OMS) pod is lowered toward the orbiter Discovery for installation. The Orbital Maneuvering System provides the thrust for orbit insertion, orbit circularization, orbit transfer, rendezvous, deorbit, abort to orbit and abort once around. It can provide up to 1,000 pounds of propellant to the aft reaction control system. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers.
2004-04-21
KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, the left-hand Orbital Maneuvering System (OMS) pod is maneuvered toward the engine interfaces on the orbiter Discovery for installation. The Orbital Maneuvering System provides the thrust for orbit insertion, orbit circularization, orbit transfer, rendezvous, deorbit, abort to orbit and abort once around. It can provide up to 1,000 pounds of propellant to the aft reaction control system. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers.
Methods for simulation-based analysis of fluid-structure interaction.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Barone, Matthew Franklin; Payne, Jeffrey L.
2005-10-01
Methods for analysis of fluid-structure interaction using high fidelity simulations are critically reviewed. First, a literature review of modern numerical techniques for simulation of aeroelastic phenomena is presented. The review focuses on methods contained within the arbitrary Lagrangian-Eulerian (ALE) framework for coupling computational fluid dynamics codes to computational structural mechanics codes. The review treats mesh movement algorithms, the role of the geometric conservation law, time advancement schemes, wetted surface interface strategies, and some representative applications. The complexity and computational expense of coupled Navier-Stokes/structural dynamics simulations points to the need for reduced order modeling to facilitate parametric analysis. The proper orthogonalmore » decomposition (POD)/Galerkin projection approach for building a reduced order model (ROM) is presented, along with ideas for extension of the methodology to allow construction of ROMs based on data generated from ALE simulations.« less
USDA-ARS?s Scientific Manuscript database
Increasing the peanut (Arachis hypogea L.) digger efficiency by accurate placement over the target rows could minimize damaged pods and yield losses. Producers have traditionally relied solely on tractor operator skills to harvest peanuts. However, as peanut production has shifted to new growing reg...
A Survey of Some Approaches to Distributed Data Base & Distributed File System Architecture.
1980-01-01
BUS POD A DD A 12 12 A = A Cell D = D Cell Figure 7-1: MUFFIN logical architecture - 45 - MUFI January 1980 ".-.Bus Interface V Conventional Processor...and Applied Mathematics (14), * December, 1966. [Kimbleton 791 Kimbleton, Stephen; Wang, Pearl; and Fong, Elizabeth. XNDM: An Experimental Network
Carvalho, Margarida; Roca, Christophe; Reis, Maria A M
2014-10-01
Carob pods are a by-product of locust bean gum industry containing more than 50% (w/w) sucrose, glucose and fructose. In this work, carob pod water extracts were used, for the first time, for succinic acid production by Actinobacillus succinogenes 130Z. Kinetic studies of glucose, fructose and sucrose consumption as individual carbon sources till 30g/L showed no inhibition on cell growth, sugar consumption and SA production rates. Sugar extraction from carob pods was optimized varying solid/liquid ratio and extraction time, maximizing sugar recovery while minimizing the extraction of polyphenols. Batch fermentations containing 10-15g/L total sugars resulted in a maximum specific SA production rate of 0.61Cmol/Cmol X.h, with a yield of 0.55Cmol SA/Cmol sugar and a volumetric productivity of 1.61g SA/L.h. Results demonstrate that carob pods can be a promising low cost feedstock for bio-based SA production. Copyright © 2014 Elsevier Ltd. All rights reserved.
Hypersonic shock tunnel heat transfer tests of the Space Shuttle SILTS pod configuration
NASA Technical Reports Server (NTRS)
Wittliff, C. E.
1983-01-01
Heat transfer measurements have been made on a 0.0175-scale NASA Space Shuttle orbiter model having a simulated SILTS (Shuttle Infrared Leeside Temperature Sensor) pod on top of the vertical tail. Heat transfer distributions were measured both on the pod and on the vertical tail. The test program covered Mach numbers of 8, 11 and 16 in air, at Reynolds numbers from 100,000 to 18 million, based on model length. The angle of attack ranged from 30 deg to 40 deg at sideslip angles from -2 to +2 deg. Data were obtained with 92 thin film assistance thermometers located on the SILTS pod and on the upper 30 percent of the vertical tail. Heat transfer rates measured on the vertical tail show good agreement with flight data obtained from missions STS-1, -2 and -3. The variation of heat transfer to the pod with Reynolds number, Mach number and angle of attack is discussed.
Zheng, Yuan-Bo; Ruan, Guo-Mo; Fu, Jia-Xing; Su, Zhong-Liang; Cheng, Peng; Lu, Jian-Zuo
2016-04-01
Oxidative stress may be involved in occurrence of postoperative delirium (POD) and cognitive dysfunction (POCD). 8-iso-Prostaglandin F2α (8-iso-PGF2α), an isoprostane derived from arachidonic acid via lipid peroxidation, is considered a gold standard for measuring oxidative stress. The present study aimed to investigate the ability of postoperative plasma 8-iso-PGF2α levels to predict POD and POCD in elderly patients undergoing hip fracture surgery. Postoperative plasma 8-iso-PGF2α levels of 182 patients were measured by an enzyme-linked immunosorbent assay. We assessed the relationships between plasma 8-iso-PGF2α levels and the risk of POD and POCD using a multivariate analysis. Plasma 8-iso-PGF2α levels and age were identified as the independent predictors for POD and POCD. Based on areas under receiver operating characteristic curve, the predictive values of 8-iso-PGF2α were obviously higher than those of age for POD and POCD. In a combined logistic-regression model, 8-iso-PGF2α significantly enhanced the areas under curve of age for prediction of POD and POCD. Postoperative plasma 8-iso-PGF2α levels may have the potential to predict POD and POCD in elder patients undergoing hip fracture surgery. Copyright © 2016 Elsevier B.V. All rights reserved.
McMillan, Matthew T; Malleo, Giuseppe; Bassi, Claudio; Butturini, Giovanni; Salvia, Roberto; Roses, Robert E; Lee, Major K; Fraker, Douglas L; Drebin, Jeffrey A; Vollmer, Charles M
2015-10-01
A recent randomized trial used the Fistula Risk Score (FRS) to develop guidelines for selective drainage based on clinically relevant fistula (CR-POPF) risk. Additionally, postoperative day (POD) 1 drain and serum amylase have been identified as accurate postoperative predictors of CR-POPF. This study sought to identify patients who may benefit from selective drainage, as well as the optimal timing for drain removal after pancreatoduodenectomy. One hundred six pancreatoduodenectomies from a previously reported RCT were assessed using risk-adjustment. The incidence of CR-POPF was compared between FRS risk cohorts. Drain and serum amylase values from POD 1 were evaluated using receiver operating characteristic (ROC) analysis to establish cut-offs predictive of CR-POPF occurrence. A regression analysis compared drain removal randomizations (POD 3 vs POD 5). Three-quarters of patients had moderate/high CR-POPF risk. This group had a CR-POPF rate of 36.3% vs 7.7% among negligible/low risk patients (p = 0.005). The areas under the ROC curve for CR-POPF prediction using POD 1 drain and serum amylase values were 0.800 (p = 0.000001; 95% CI 0.70-0.90) and 0.655 (p = 0.012; 95% CI 0.55-0.77), respectively. No significant serum amylase cut-offs were identified. Moderate/high risk patients with POD 1 drain amylase ≤ 5,000 U/L had significantly lower rates of CR-POPF when randomized to POD 3 drain removal (4.2% vs 38.5%; p = 0.003); moreover, these patients experienced fewer complications and shorter hospital stays. A clinical care protocol is proposed whereby drains are recommended for moderate/high FRS risk patients, but may be omitted in patients with negligible/low risk. Drain amylase values in moderate/high risk patients should then be evaluated on POD 1 to determine the optimal timing for drain removal. Moderate/high risk patients with POD 1 drain amylase ≤ 5,000 U/L have lower rates of CR-POPF with POD 3 (vs POD ≥ 5) drain removal; early drain removal is recommended for these patients. Copyright © 2015 American College of Surgeons. Published by Elsevier Inc. All rights reserved.
Karapanos, Ioannis; Papandreou, Anastasia; Skouloudi, Marianna; Makrogianni, Despoina; Fernández, Juan A; Rosa, Eduardo; Ntatsi, Georgia; Bebeli, Penelope J; Savvas, Dimitrios
2017-10-01
Cowpea is traditionally cultivated in some regions of southern Europe for its dried seeds; however, there is a scarcity of information on the quality and dietary characteristics of fresh pods, which are occasionally used in folk diets. This paper aims at covering this gap in knowledge, thereby contributing to the dissemination of fresh cowpea pods as a novel product for the market. The quality and dietary characteristics of pods from 37 accessions (Vigna unguiculata ssp. unguiculata and ssp. sesquipedalis) grown in southern Europe were assessed in an attempt to provide information on pod quality and nutritional properties and to identify relationships between quality traits and accession origin. Pods from the sesquipedalis accessions were heavier and larger, and reached commercial maturity 2 days later, than those from the unguiculata accessions. There were also large differences in the quality and dietary characteristics of the accessions. The pods of most accessions were rich in proteins, chlorophylls, carotenoids and phenolics, and showed high antioxidant activity and low concentrations of nitrates and raffinose-family oligosaccharides. Cluster analysis based on quality, dietary or antinutritional traits did not reveal any apparent grouping among the accessions. All the quality characteristics were independent of accession origin and subspecies. Most of the accessions produced fresh pods of good quality and high dietary value, suitable for introduction in the market and/or for use as valuable genetic material for the development of new improved varieties. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.
A POD reduced order model for resolving angular direction in neutron/photon transport problems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Buchan, A.G., E-mail: andrew.buchan@imperial.ac.uk; Calloo, A.A.; Goffin, M.G.
2015-09-01
This article presents the first Reduced Order Model (ROM) that efficiently resolves the angular dimension of the time independent, mono-energetic Boltzmann Transport Equation (BTE). It is based on Proper Orthogonal Decomposition (POD) and uses the method of snapshots to form optimal basis functions for resolving the direction of particle travel in neutron/photon transport problems. A unique element of this work is that the snapshots are formed from the vector of angular coefficients relating to a high resolution expansion of the BTE's angular dimension. In addition, the individual snapshots are not recorded through time, as in standard POD, but instead theymore » are recorded through space. In essence this work swaps the roles of the dimensions space and time in standard POD methods, with angle and space respectively. It is shown here how the POD model can be formed from the POD basis functions in a highly efficient manner. The model is then applied to two radiation problems; one involving the transport of radiation through a shield and the other through an infinite array of pins. Both problems are selected for their complex angular flux solutions in order to provide an appropriate demonstration of the model's capabilities. It is shown that the POD model can resolve these fluxes efficiently and accurately. In comparison to high resolution models this POD model can reduce the size of a problem by up to two orders of magnitude without compromising accuracy. Solving times are also reduced by similar factors.« less
Contribution of the pod wall to seed grain filling in alfalfa.
Wang, Hui; Hou, Longyu; Wang, Mingya; Mao, Peisheng
2016-05-23
Three genotypes of alfalfa viz. Medicago sativa (Zhongmu No. 1, Zhongmu No. 2) and M. varia (Caoyuan No. 3) grown in the filed were investigated for the contribution of pod wall and leaves by shading all pods and leaves on July 15, 20 and 25, respectively. Date was recorded for total pod weight (TPW), pod wall weight (PWW), seed weight per pod (SWP), seed number per pod (SNP) and single seed weight (SSW) of one-coil and two-coil spiral pods. TPW, SNP, PWW and SWP were reduced by shading all leaves or pods, whereas SSW was not significantly affected. The relative photosynthetic contribution of pod wall to SWP was 25.6-48.1% in three genotypes on July 15. The pod wall in one-coil spiral pods generated a greater relative contribution to the TPW and SWP than in two-coil spiral pods. In the last stage (July 25), the relative photosynthetic contribution of leaves to SWP sharply decreased, whereas the relative photosynthetic contribution of pod wall to SWP was stable in the late stage (July 20 and 25). In conclusion, the pod wall of alfalfa could carry out photosynthesis and the pod wall played an important role in pod filling at the late growth stage.
Precise orbit determination for BDS3 experimental satellites using iGMAS and MGEX tracking networks
NASA Astrophysics Data System (ADS)
Li, Xingxing; Yuan, Yongqiang; Zhu, Yiting; Huang, Jiande; Wu, Jiaqi; Xiong, Yun; Zhang, Xiaohong; Li, Xin
2018-04-01
In this contribution, we focus on the precise orbit determination (POD) for BDS3 experimental satellites with the international GNSS Monitoring and Assessment System (iGMAS) and Multi-GNSS Experiment (MGEX) tracking networks. The datasets of DOY (day of year) 001-230 in 2017 are analyzed with different processing strategies. By comparing receiver clock biases and receiver B1I-B3I DCBs, it is confirmed that there is no obvious systematic bias between experimental BDS3 and BDS2 in the common B1I and B3I signals, which indicates that experimental BDS3 and BDS2 can be treated as one system when performing combined POD. With iGMAS-only BDS3 stations, the 24-h overlap RMS of BDS3 + BDS2 + GPS combined POD is 24.3, 16.1 and 8.4 cm in along-track, cross-track and radial components, which is better than BDS3-only POD by 80-90% and better than BDS3+BDS2 combined POD by about 10%. With more stations (totally 20 stations from both iGMAS and MGEX) and the proper ambiguity resolution strategy (GEO ambiguities are float and BDS3 ambiguities are fixed), the performance of BDS3 POD can be further improved to 14.6, 7.9 and 3.7 cm, respectively, in along-track, cross-track and radial components, which is comparable to the performance of BDS2 POD. The 230-day SLR validations of C32, C33 and C34 show that the mean differences of - 3.48 , 7.81 and 8.19 cm can be achieved, while the STD is 13.35, 13.46 and 13.11 cm, respectively. Furthermore, the 230-day overlap comparisons reveal that C31 most likely still uses an orbit-normal mode and exhibits similar orbit modeling problems in orbit-normal periods as found in most of the BDS2 satellites.
Glatz, Torben; Lederer, Ann-Kathrin; Kulemann, Birte; Seifert, Gabriel; Holzner, Philipp Anton; Hopt, Ulrich Theodor; Hoeppner, Jens; Marjanovic, Goran
2015-10-06
Clinical data indicate that laparoscopic surgery reduces postoperative inflammatory response and benefits patient recovery. Little is known about the mechanisms involved in reduced systemic and local inflammation and the contribution of reduced trauma to the abdominal wall and the parietal peritoneum. Included were 61 patients, who underwent elective colorectal resection without intraabdominal complications; 17 received a completely laparoscopic, 13 a laparoscopically- assisted procedure and 31 open surgery. Local inflammatory response was quantified by measurement of intraperitoneal leukocytes and IL-6 levels during the first 4 days after surgery. There was no statistical difference between the groups in systemic inflammatory parameters and intraperitoneal leukocytes. Intraperitoneal interleukin-6 was significantly lower in the laparoscopic group than in the laparoscopically-assisted and open group on postoperative day 1 (26.16 versus 43.25 versus 40.83 ng/ml; p = 0.001). No difference between the groups was recorded on POD 2-4. Intraperitoneal interleukin-6 showed a correlation with duration of hospital stay on POD 1 (0.233, p = 0.036), but not on POD 2-4. Patients who developed a surgical wound infection showed higher levels of intraperitoneal interleukin-6 on postoperative day 2-4 (POD 2: 42.56 versus 30.02 ng/ml, p = 0.03), POD 3: 36.52 versus 23.62 ng/ml, p = 0.06 and POD 4: 34.43 versus 19.99 ng/ml, p = 0.046). Extraabdominal infections had no impact. The analysis shows an attenuated intraperitoneal inflammatory response on POD 1 in completely laparoscopically-operated patients, associated with a quicker recovery. This effect cannot be observed in patients, who underwent a laparoscopically-assisted or open procedure. Factors inflicting additional trauma to the abdominal wall and parietal peritoneum promote the intraperitoneal inflammation process.
Development of kairomone based control programs for cocoa pod borer
USDA-ARS?s Scientific Manuscript database
The Cocoa Pod Borer moth presents a unique opportunity to develop host volatile attractants for control strategies for the following reasons. First, knowing what volatiles are critical for host finding by females will allow for development of mass trapping and/or attract and kill strategies to cont...
Naik, Bhiken I; Tsang, Siny; Knisely, Anne; Yerra, Sandeep; Durieux, Marcel E
2017-01-31
Enhanced recovery after surgery (ERAS) programs typically utilizes multi-modal analgesia to reduce perioperative opioid consumption. Systemic lidocaine is used in several of these ERAS algorithms and has been shown to reduce opioid use after colorectal surgery. However it is unclear how much the other components of an ERAS protocol contribute to the final outcome. Using a noninferiority analysis we sought to assess the role of perioperative lidocaine in an ERAS program for colorectal surgery, using pain and opioid consumption as outcomes. We conducted a retrospective review of patients who had received intravenous lidocaine perioperatively during colorectal surgery. We matched them with patients who were managed using a multi-component ERAS protocol, which included perioperative lidocaine. We tested a joint hypothesis of noninferiority of lidocaine infusion to ERAS protocol in postoperative pain scores and opioid consumption. We assigned a noninferiority margin of 1 point (on an 11-point numerical rating scale) difference in pain and a ratio [mean (lidocaine) / mean (ERAS)] of 1.2 in opioid consumption, respectively. Fifty-two patients in the lidocaine group were matched with patients in the ERAS group. With regards to opioid consumption, in the overall [1.68 (1.43-1.98)] [odds ratio (95% confidence interval)] analysis and on postoperative day (POD) 1 [2.38 (1.74-3.31)] lidocaine alone was inferior to multi-modal analgesia. On POD 2 and beyond, although the mean odds ratio for opioid consumption was 1.43 [1.43 (1.17-1.73)], the lower limit extended beyond the pre-defined cut-off of 1.2, rendering the outcome inconclusive. For pain scores lidocaine is non-inferior to ERAS [-0.17 (-1.08-0.74)] on POD 2 and beyond. Pain scores on POD 1 and in the overall cohort were inconclusive based on the noninferiority analysis. The addition of a multi-component ERAS protocol to intravenous lidocaine incrementally reduces opioid consumption, most evident on POD 1. For pain scores the data is inconclusive on POD 1, however on POD 2 and beyond lidocaine alone is non-inferior to an ERAS program with lidocaine. Opioid-related complications, including return of bowel function, were not different between the groups despite reduced opioid use in the ERAS group.
2012-06-19
CAPE CANAVERAL, Fla. – Inside Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, United Space Alliance technicians monitor the progress as a large crane is lowered toward the right orbital maneuvering system, or OMS, pod for space shuttle Atlantis. It will be the last time an OMS pod is installed on Atlantis. The OMS provided the shuttle with thrust for orbit insertion, rendezvous and deorbit, and could provide up to 1,000 pounds of propellant to the aft reaction control system. The OMS is housed in two independent pods located on each side of the shuttle’s aft fuselage. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers. Atlantis’ OMS pods were removed and sent to the test facility at White Sands Space Harbor in New Mexico to be cleaned of residual toxic propellant. The work is part of the Space Shuttle Program’s transition and retirement processing of the space shuttle fleet. A groundbreaking was held Jan. 18 for Atlantis’ future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/transition. Photo credit: NASA/Dimitri Gerondidakis
2012-06-19
CAPE CANAVERAL, Fla. – In a view from above inside Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, United Space Alliance technicians monitor the progress as a crane is attached to the right orbital maneuvering system, or OMS, pod for space shuttle Atlantis. It is the last time an OMS pod will be installed on Atlantis. The OMS provided the shuttle with thrust for orbit insertion, rendezvous and deorbit, and could provide up to 1,000 pounds of propellant to the aft reaction control system. The OMS is housed in two independent pods located on each side of the shuttle’s aft fuselage. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers. Atlantis’ OMS pods were removed and sent to the test facility at White Sands Space Harbor in New Mexico to be cleaned of residual toxic propellant. The work is part of the Space Shuttle Program’s transition and retirement processing of the space shuttle fleet. A groundbreaking was held Jan. 18 for Atlantis’ future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/transition. Photo credit: NASA/Dimitri Gerondidakis
2012-06-19
CAPE CANAVERAL, Fla. – Inside Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, United Space Alliance technicians monitor the progress as a large crane moves the right orbital maneuvering system, or OMS, pod closer to space shuttle Atlantis. It is the last time an OMS pod will be installed on Atlantis. The OMS provided the shuttle with thrust for orbit insertion, rendezvous and deorbit, and could provide up to 1,000 pounds of propellant to the aft reaction control system. The OMS is housed in two independent pods located on each side of the shuttle’s aft fuselage. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers. Atlantis’ OMS pods were removed and sent to the test facility at White Sands Space Harbor in New Mexico to be cleaned of residual toxic propellant. The work is part of the Space Shuttle Program’s transition and retirement processing of the space shuttle fleet. A groundbreaking was held Jan. 18 for Atlantis’ future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/transition. Photo credit: NASA/Dimitri Gerondidakis
2012-06-19
CAPE CANAVERAL, Fla. – Inside Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, United Space Alliance technicians monitor the progress as a large crane lowers the right orbital maneuvering system, or OMS, pod onto space shuttle Atlantis. It is the last time an OMS pod will be installed on Atlantis. The OMS provided the shuttle with thrust for orbit insertion, rendezvous and deorbit, and could provide up to 1,000 pounds of propellant to the aft reaction control system. The OMS is housed in two independent pods located on each side of the shuttle’s aft fuselage. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers. Atlantis’ OMS pods were removed and sent to the test facility at White Sands Space Harbor in New Mexico to be cleaned of residual toxic propellant. The work is part of the Space Shuttle Program’s transition and retirement processing of the space shuttle fleet. A groundbreaking was held Jan. 18 for Atlantis’ future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/transition. Photo credit: NASA/Dimitri Gerondidakis
2012-06-19
CAPE CANAVERAL, Fla. – Inside Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, United Launch Alliance technicians provide assistance as a large crane is lowered toward the right orbital maneuvering system, or OMS, pod for space shuttle Atlantis. It will be the last time an OMS pod is installed on Atlantis. The OMS provided the shuttle with thrust for orbit insertion, rendezvous and deorbit, and could provide up to 1,000 pounds of propellant to the aft reaction control system. The OMS is housed in two independent pods located on each side of the shuttle’s aft fuselage. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers. Atlantis’ OMS pods were removed and sent to the test facility at White Sands Space Harbor in New Mexico to be cleaned of residual toxic propellant. The work is part of the Space Shuttle Program’s transition and retirement processing of the space shuttle fleet. A groundbreaking was held Jan. 18 for Atlantis’ future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/transition. Photo credit: NASA/Dimitri Gerondidakis
2012-06-19
CAPE CANAVERAL, Fla. – Inside Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, United Space Alliance technicians monitor the progress as a large crane moves the right orbital maneuvering system, or OMS, pod closer to space shuttle Atlantis. It is the last time an OMS pod will be installed on Atlantis. The OMS provided the shuttle with thrust for orbit insertion, rendezvous and deorbit, and could provide up to 1,000 pounds of propellant to the aft reaction control system. The OMS is housed in two independent pods located on each side of the shuttle’s aft fuselage. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers. Atlantis’ OMS pods were removed and sent to the test facility at White Sands Space Harbor in New Mexico to be cleaned of residual toxic propellant. The work is part of the Space Shuttle Program’s transition and retirement processing of the space shuttle fleet. A groundbreaking was held Jan. 18 for Atlantis’ future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/transition. Photo credit: NASA/Dimitri Gerondidakis
2012-06-19
CAPE CANAVERAL, Fla. – Inside Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, a United Space Alliance technician monitors the progress as a large crane lifts the right orbital maneuvering system, or OMS, pod for installation on space shuttle Atlantis. It is the last time an OMS pod will be installed on Atlantis. The OMS provided the shuttle with thrust for orbit insertion, rendezvous and deorbit, and could provide up to 1,000 pounds of propellant to the aft reaction control system. The OMS is housed in two independent pods located on each side of the shuttle’s aft fuselage. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers. Atlantis’ OMS pods were removed and sent to the test facility at White Sands Space Harbor in New Mexico to be cleaned of residual toxic propellant. The work is part of the Space Shuttle Program’s transition and retirement processing of the space shuttle fleet. A groundbreaking was held Jan. 18 for Atlantis’ future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/transition. Photo credit: NASA/Dimitri Gerondidakis
2012-06-19
CAPE CANAVERAL, Fla. – Inside Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, a unique close-up view shows a large crane lowering the right orbital maneuvering system, or OMS, pod closer to space shuttle Atlantis. It is the last time an OMS pod will be installed on Atlantis. The OMS provided the shuttle with thrust for orbit insertion, rendezvous and deorbit, and could provide up to 1,000 pounds of propellant to the aft reaction control system. The OMS is housed in two independent pods located on each side of the shuttle’s aft fuselage. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers. Atlantis’ OMS pods were removed and sent to the test facility at White Sands Space Harbor in New Mexico to be cleaned of residual toxic propellant. The work is part of the Space Shuttle Program’s transition and retirement processing of the space shuttle fleet. A groundbreaking was held Jan. 18 for Atlantis’ future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/transition. Photo credit: NASA/Dimitri Gerondidakis
2012-06-19
CAPE CANAVERAL, Fla. – Inside Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, a United Space Alliance technician monitors the progress as a large crane lifts the right orbital maneuvering system, or OMS, pod for installation on space shuttle Atlantis. It is the last time an OMS pod will be installed on Atlantis. The OMS provided the shuttle with thrust for orbit insertion, rendezvous and deorbit, and could provide up to 1,000 pounds of propellant to the aft reaction control system. The OMS is housed in two independent pods located on each side of the shuttle’s aft fuselage. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers. Atlantis’ OMS pods were removed and sent to the test facility at White Sands Space Harbor in New Mexico to be cleaned of residual toxic propellant. The work is part of the Space Shuttle Program’s transition and retirement processing of the space shuttle fleet. A groundbreaking was held Jan. 18 for Atlantis’ future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/transition. Photo credit: NASA/Dimitri Gerondidakis
2012-06-19
CAPE CANAVERAL, Fla. – Inside Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, United Launch Alliance technicians monitor the progress as a large crane moves the right orbital maneuvering system, or OMS, pod for installation on space shuttle Atlantis. It will be the last time an OMS pod is installed on Atlantis. The OMS provided the shuttle with thrust for orbit insertion, rendezvous and deorbit, and could provide up to 1,000 pounds of propellant to the aft reaction control system. The OMS is housed in two independent pods located on each side of the shuttle’s aft fuselage. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers. Atlantis’ OMS pods were removed and sent to the test facility at White Sands Space Harbor in New Mexico to be cleaned of residual toxic propellant. The work is part of the Space Shuttle Program’s transition and retirement processing of the space shuttle fleet. A groundbreaking was held Jan. 18 for Atlantis’ future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/transition. Photo credit: NASA/Dimitri Gerondidakis
2012-06-19
CAPE CANAVERAL, Fla. – Inside Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, United Space Alliance technicians monitor the progress as a large crane lifts the right orbital maneuvering system, or OMS, pod for installation on space shuttle Atlantis. It is the last time an OMS pod will be installed on Atlantis. The OMS provided the shuttle with thrust for orbit insertion, rendezvous and deorbit, and could provide up to 1,000 pounds of propellant to the aft reaction control system. The OMS is housed in two independent pods located on each side of the shuttle’s aft fuselage. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers. Atlantis’ OMS pods were removed and sent to the test facility at White Sands Space Harbor in New Mexico to be cleaned of residual toxic propellant. The work is part of the Space Shuttle Program’s transition and retirement processing of the space shuttle fleet. A groundbreaking was held Jan. 18 for Atlantis’ future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/transition. Photo credit: NASA/Dimitri Gerondidakis
2012-06-19
CAPE CANAVERAL, Fla. – Inside Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, a unique close-up view shows a large crane lowering the right orbital maneuvering system, or OMS, pod closer to space shuttle Atlantis. It is the last time an OMS pod will be installed on Atlantis. The OMS provided the shuttle with thrust for orbit insertion, rendezvous and deorbit, and could provide up to 1,000 pounds of propellant to the aft reaction control system. The OMS is housed in two independent pods located on each side of the shuttle’s aft fuselage. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers. Atlantis’ OMS pods were removed and sent to the test facility at White Sands Space Harbor in New Mexico to be cleaned of residual toxic propellant. The work is part of the Space Shuttle Program’s transition and retirement processing of the space shuttle fleet. A groundbreaking was held Jan. 18 for Atlantis’ future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/transition. Photo credit: NASA/Dimitri Gerondidakis
2012-06-19
CAPE CANAVERAL, Fla. – Inside Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, United Space Alliance technicians monitor the progress as a large crane begins to lift the right orbital maneuvering system, or OMS, pod for installation on space shuttle Atlantis. It is the last time an OMS pod will be installed on Atlantis. The OMS provided the shuttle with thrust for orbit insertion, rendezvous and deorbit, and could provide up to 1,000 pounds of propellant to the aft reaction control system. The OMS is housed in two independent pods located on each side of the shuttle’s aft fuselage. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers. Atlantis’ OMS pods were removed and sent to the test facility at White Sands Space Harbor in New Mexico to be cleaned of residual toxic propellant. The work is part of the Space Shuttle Program’s transition and retirement processing of the space shuttle fleet. A groundbreaking was held Jan. 18 for Atlantis’ future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/transition. Photo credit: NASA/Dimitri Gerondidakis
2012-06-19
CAPE CANAVERAL, Fla. – Inside Orbiter Processing Facility-1 at NASA’s Kennedy Space Center in Florida, United Space Alliance technicians monitor the progress as a large crane begins to lift the right orbital maneuvering system, or OMS, pod for installation on space shuttle Atlantis. It is the last time an OMS pod will be installed on Atlantis. The OMS provided the shuttle with thrust for orbit insertion, rendezvous and deorbit, and could provide up to 1,000 pounds of propellant to the aft reaction control system. The OMS is housed in two independent pods located on each side of the shuttle’s aft fuselage. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers. Atlantis’ OMS pods were removed and sent to the test facility at White Sands Space Harbor in New Mexico to be cleaned of residual toxic propellant. The work is part of the Space Shuttle Program’s transition and retirement processing of the space shuttle fleet. A groundbreaking was held Jan. 18 for Atlantis’ future home, a 65,000-square-foot exhibit hall in Shuttle Plaza at the Kennedy Space Center Visitor Complex. Atlantis is scheduled to roll over to the visitor complex in November in preparation for the exhibit’s grand opening in July 2013. For more information, visit http://www.nasa.gov/transition. Photo credit: NASA/Dimitri Gerondidakis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jambon, E.; Petitpierre, F.; Brizzi, V.
PurposeTo retrospectively investigate the safety and efficacy of hybrid proximal coiling of various medium-sized vessels (4 to 8 mm) using the Penumbra Occlusion Device (POD).Materials and MethodsFrom October 2014 to February 2016, 37 proximal embolizations were performed with PODs in 36 patients (mean age: 50.8, range: 10–86; 29 male, 7 female). Vessel occlusions were achieved under fluoroscopic guidance using a 2.7 French microcatheter. Among the 36 vessels targeted, 16 were splenic arteries, 11 renal arteries, 4 mesenteric arteries, 3 arteriovenous fistulae, 1 iliac artery, and 1 gonadal vein. Intermittent follow-up angiography was performed to assess the flow for final occlusion. Outcomesmore » and complications were assessed by clinical and/or imaging follow-up.ResultsTo produce proximal occlusion of the intended vessels, the POD was used alone in 19 embolizations (51.4 %). In 12 procedures (32.4 %), POD was used as a coil constrainer to secure the coil construct. In 6 procedures (16.2 %), additional embolic devices were used to achieve vessel occlusion after initial POD deployment. After a mean follow-up of 3.2 months, no POD migration was observed but two complications occurred (5.4 %): one post embolic syndrome and one extensive infarction with splenic abscess.ConclusionThe POD system allows safe and effective proximal embolization of medium-sized vessels in a variety of clinical settings.« less
Das, Shouvik; Singh, Mohar; Srivastava, Rishi; Bajaj, Deepak; Saxena, Maneesha S.; Rana, Jai C.; Bansal, Kailash C.; Tyagi, Akhilesh K.; Parida, Swarup K.
2016-01-01
The present study used a whole-genome, NGS resequencing-based mQTL-seq (multiple QTL-seq) strategy in two inter-specific mapping populations (Pusa 1103 × ILWC 46 and Pusa 256 × ILWC 46) to scan the major genomic region(s) underlying QTL(s) governing pod number trait in chickpea. Essentially, the whole-genome resequencing of low and high pod number-containing parental accessions and homozygous individuals (constituting bulks) from each of these two mapping populations discovered >8 million high-quality homozygous SNPs with respect to the reference kabuli chickpea. The functional significance of the physically mapped SNPs was apparent from the identified 2,264 non-synonymous and 23,550 regulatory SNPs, with 8–10% of these SNPs-carrying genes corresponding to transcription factors and disease resistance-related proteins. The utilization of these mined SNPs in Δ (SNP index)-led QTL-seq analysis and their correlation between two mapping populations based on mQTL-seq, narrowed down two (CaqaPN4.1: 867.8 kb and CaqaPN4.2: 1.8 Mb) major genomic regions harbouring robust pod number QTLs into the high-resolution short QTL intervals (CaqbPN4.1: 637.5 kb and CaqbPN4.2: 1.28 Mb) on chickpea chromosome 4. The integration of mQTL-seq-derived one novel robust QTL with QTL region-specific association analysis delineated the regulatory (C/T) and coding (C/A) SNPs-containing one pentatricopeptide repeat (PPR) gene at a major QTL region regulating pod number in chickpea. This target gene exhibited anther, mature pollen and pod-specific expression, including pronounced higher up-regulated (∼3.5-folds) transcript expression in high pod number-containing parental accessions and homozygous individuals of two mapping populations especially during pollen and pod development. The proposed mQTL-seq-driven combinatorial strategy has profound efficacy in rapid genome-wide scanning of potential candidate gene(s) underlying trait-associated high-resolution robust QTL(s), thereby expediting genomics-assisted breeding and genetic enhancement of crop plants, including chickpea. PMID:26685680
[Effect of occupational stress on oxidation/antioxidant capacity in nurses].
Cao, Lili; Tian, Honger; Zhang, Qingdong; Zhu, Xinyun; Zhan, Yongguo; Su, Jingguo; Xu, Tian; Zhu, Huabin; Liu, Ling
2014-02-01
To investigate the effect of occupational stress on the oxidation/antioxidant capacity in nurses. A total of 131 nurses were included as study subjects. The occupational health information collection system (based on the Internet of things) was used for measurement of occupational stress. Levels of hydroxyl free radicals and antioxidant enzymes were determined. The serum level of superoxide dismutase (SOD) was the highest in nurses under the age of 30 and the lowest in those over 45 (P < 0.05). The serum levels of glutathione peroxidase (GSH-Px) and peroxidase (POD) were the highest in nurses of working age less than 5 years, followed by those of 5-15 years, and nurses with more than 25 years' working experience showed the lowest GSH-Px and POD levels (P < 0.05). Furthermore, nurses with a university (college) degree had a higher GSH-Px level and a lower POD level compared with those with junior and senior high school degrees (P < 0.05). Job prospects and job control were positive occupational stress factors for SOD. Job hazards were negative occupational stress factors for POD. Psychological satisfaction was negative occupational stress reaction for hydroxyl free radicals. Calmness was positive occupational stress reaction for SOD, and daily stress was a negative one. The positive occupational stress reactions for GSH-Px were psychological satisfaction and job satisfaction, and daily stress was negative reaction. Nurses with higher occupational stress have stronger oxidation and weaker antioxidant capacity, which intensifies oxidant-antioxidant imbalance and leads to oxidative stress damage.
Weather Radars and Lidar for Observing the Atmosphere
NASA Astrophysics Data System (ADS)
(Vivek) Vivekanandan, J.
2010-05-01
The Earth Observing Laboratory (EOL) at the National Center for Atmospheric Research (NCAR) in Boulder, Colorado develops and deploys state-of-the-art ground-based radar, airborne radar and lidar instruments to advance scientific understanding of the earth system. The ground-based radar (S-Pol) is equipped with dual-wavelength capability (S-band and Ka-band). S-Pol is the only transportable radar in the world. In order to capture faster moving weather events such as tornadoes and record observations of clouds over rugged mountainous terrain and ocean, an airborne radar (ELDORA) is used. It is the only airborne Doppler meteorological radar that is able to detect motions in the clear air. The EOL is in the process of building the first phase of a three phase dual wavelength W/Ka-band airborne cloud radar to be called the HIAPER Cloud Radar (HCR). This phase is a pod based W-band radar system with scanning capability. The second phase will add pulse compression and polarimetric capability to the W-band system, while the third phase will add complementary Ka-band radar. The pod-based radar is primarily designed to fly on the Gulfstream V (GV) and C-130 aircraft. The envisioned capability of a millimeter wave radar system on GV is enhanced by coordination with microwave radiometer, in situ probes, and especially by the NCAR GV High-Spectral Resolution Lidar (HSRL) which is also under construction. The presentation will describe the capabilities of current instruments and also planned instrumentation development.
Using Airborne Lidar Data from IcePod to Measure Annual and Seasonal Ice Changes Over Greenland
NASA Astrophysics Data System (ADS)
Frearson, N.; Bertinato, C.; Das, I.
2014-12-01
The IcePod is a multi-sensor airborne science platform that supports a wide suite of instruments, including a Riegl VQ-580 infrared scanning laser, GPS-inertial positioning system, shallow and deep-ice radars, visible-wave and infrared cameras, and upward-looking pyrometer. These instruments allow us to image the ice from top to bottom, including the surface of melt-water plumes that originate at the ice-ocean boundary. In collaboration with the New York Air National Guard 109th Airlift Wing, the IcePod is flown on LC-130 aircraft, which presents the unique opportunity to routinely image the Greenland ice sheet several times within a season. This is particularly important for mass balance studies, as we can measure elevation changes during the melt season. During the 2014 summer, laser data was collected via IcePod over the Greenland ice sheet, including Russell Glacier, Jakobshavn Glacier, Eqip Glacier, and Summit Camp. The Icepod will also be routinely operated in Antarctica. We present the initial testing, calibration, and error estimates from the first set of laser data that were collected on IcePod. At a survey altitude of 1000 m, the laser swath covers ~ 1000 m. A Northrop-Grumman LN-200 tactical grade IMU is rigidly attached to the laser scanner to provide attitude data at a rate of 200 Hz. Several methods were used to determine the lever arm between the IMU center of navigation and GPS antenna phase center, terrestrial scanning laser, total station survey, and optimal estimation. Additionally, initial bore sight calibration flights yielded misalignment angles within an accuracy of ±4 cm. We also performed routine passes over the airport ramp in Kangerlussuaq, Greenland, comparing the airborne GPS and Lidar data to a reference GPS-based ground survey across the ramp, spot GPS points on the ramp and a nearby GPS base station. Positioning errors can severely impact the accuracy of a laser altimeter when flying over remote regions such as across the ice sheets. Setting up GPS base stations along the flight track can prove to be logistically challenging. We have processed the GPS-inertial data using both DGPS and PPP and present the comparison of those results here. Finally, we discuss our processing, calibration and error estimation methods and compare our results to previously flown IceBridge lines.
2004-04-21
KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, workers stand by as the left-hand Orbital Maneuvering System (OMS) pod is maneuvered toward the engine interfaces on the orbiter Discovery for installation. The Orbital Maneuvering System provides the thrust for orbit insertion, orbit circularization, orbit transfer, rendezvous, deorbit, abort to orbit and abort once around. It can provide up to 1,000 pounds of propellant to the aft reaction control system. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers.
2004-04-21
KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, the left-hand Orbital Maneuvering System (OMS) pod (top of photo) is poised behind the engine interfaces on the orbiter Discovery for installation. The Orbital Maneuvering System provides the thrust for orbit insertion, orbit circularization, orbit transfer, rendezvous, deorbit, abort to orbit and abort once around. It can provide up to 1,000 pounds of propellant to the aft reaction control system. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers.
2004-04-21
KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, workers on an upper level watch as the left-hand Orbital Maneuvering System (OMS) pod is lifted high to maneuver it toward the orbiter Discovery for installation. The Orbital Maneuvering System provides the thrust for orbit insertion, orbit circularization, orbit transfer, rendezvous, deorbit, abort to orbit and abort once around. It can provide up to 1,000 pounds of propellant to the aft reaction control system. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers.
2004-04-21
KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, a worker on an upper level watches as the left-hand Orbital Maneuvering System (OMS) pod is lifted high to maneuver it toward the orbiter Discovery for installation. The Orbital Maneuvering System provides the thrust for orbit insertion, orbit circularization, orbit transfer, rendezvous, deorbit, abort to orbit and abort once around. It can provide up to 1,000 pounds of propellant to the aft reaction control system. Each pod contains one OMS engine and the hardware needed to pressurize, store and distribute the propellants to perform the velocity maneuvers.
POD/MAC-Based Modal Basis Selection for a Reduced Order Nonlinear Response Analysis
NASA Technical Reports Server (NTRS)
Rizzi, Stephen A.; Przekop, Adam
2007-01-01
A feasibility study was conducted to explore the applicability of a POD/MAC basis selection technique to a nonlinear structural response analysis. For the case studied the application of the POD/MAC technique resulted in a substantial improvement of the reduced order simulation when compared to a classic approach utilizing only low frequency modes present in the excitation bandwidth. Further studies are aimed to expand application of the presented technique to more complex structures including non-planar and two-dimensional configurations. For non-planar structures the separation of different displacement components may not be necessary or desirable.
iPod touch-assisted instrumentation of the spine: a technical report.
Jost, Gregory F; Bisson, Erica F; Schmidt, Meic H
2013-12-01
Instrumentation of the spine depends on choosing the correct insertion angles to implant screws. Although modern image guidance facilitates precise instrumentation of the spine, the equipment is costly and availability is limited. Although most surgeons use lateral fluoroscopy to guide instrumentation in the sagittal plane, the lateromedial angulation is often chosen by estimation. To overcome the associated uncertainty, iPod touch-based applications for measuring angles can be used to assist with screw implantation. To evaluate the use of the iPod touch to adjust instruments to the optimal axial insertion angle for placement of pedicle screws in the lumbar spine. Twenty lumbar pedicle screws in 5 consecutive patients were implanted using the iPod touch. The lateromedial angulation was measured on preoperative images and reproduced in the operative field with the iPod touch. The instruments to implant the screws were aligned with the side of the iPod for screw insertion. Actual screw angles were remeasured on postoperative imaging. We collected demographic, clinical, and operative data for each patient. In 16 of 20 screws, the accuracy of implantation was within 3 degrees of the ideal trajectory. The 4 screws with an angle mismatch of 7 to 13 degrees were all implanted at the caudal end of the exposure, where maintaining the planned angulation was impeded by strong muscles pushing medially. iPod touch-assisted instrumentation of the spine is a very simple technique, which, in combination with a lateral fluoroscopy, may guide placement of pedicle screws in the lumbar spine.
USDA-ARS?s Scientific Manuscript database
We report on the assembly of the 14,146 base pairs (bp) near complete mitochondrial sequencing of the legume pod borer (LPB), Maruca vitrata (Lepidoptera: Crambidae), which was used to estimate divergence and relationships within the lepidopteran lineage. Arrangement and orientation of 13 protein c...
Spitzer, James D; Hupert, Nathaniel; Duckart, Jonathan; Xiong, Wei
2007-01-01
Community-based mass prophylaxis is a core public health operational competency, but staffing needs may overwhelm the local trained health workforce. Just-in-time (JIT) training of emergency staff and computer modeling of workforce requirements represent two complementary approaches to address this logistical problem. Multnomah County, Oregon, conducted a high-throughput point of dispensing (POD) exercise to test JIT training and computer modeling to validate POD staffing estimates. The POD had 84% non-health-care worker staff and processed 500 patients per hour. Post-exercise modeling replicated observed staff utilization levels and queue formation, including development and amelioration of a large medical evaluation queue caused by lengthy processing times and understaffing in the first half-hour of the exercise. The exercise confirmed the feasibility of using JIT training for high-throughput antibiotic dispensing clinics staffed largely by nonmedical professionals. Patient processing times varied over the course of the exercise, with important implications for both staff reallocation and future POD modeling efforts. Overall underutilization of staff revealed the opportunity for greater efficiencies and even higher future throughputs.
Du, Feng; Shi, Huijun; Zhang, Xingchang; Xu, Xuexuan
2014-01-01
Drought can impact local vegetation dynamics in a long term. In order to predict the possible successional pathway of local community under drought, the responses of some drought resistance indices of six successional seral species in the semi-arid Loss Hilly Region of China were illustrated and compared on three levels of soil water deficits along three growing months (7, 8 and 9). The results showed that: 1) the six species had significant differences in SOD, POD activities and MDA content. The rank correlations between SOD, POD activities and the successional niche positions of the six species were positive, and the correlation between MDA content and the niche positions was negative; 2) activities of SOD, CAT and POD, and content of proline and MDA had significant differences among the three months; 3) there existed significant interactions of SOD, CAT, POD activities and MDA content between months and species. With an exception, no interaction of proline was found. Proline in leaves had a general decline in reproductive month; 4) SOD, CAT, POD activities and proline content had negative correlations with MDA content. Among which, the correlation between SOD activity and MDA content was significant. The results implied that, in arid or semiarid region, the species at later successional stage tend to have strong drought resistance than those at early stage. Anti-drought indices can partially interpret the pathway of community succession in the drought impacted area. SOD activity is more distinct and important on the scope of protecting membrane damage through the scavenging of ROS on exposure to drought. PMID:24914928
Development of POD from in-service NDI data
NASA Astrophysics Data System (ADS)
Forsyth, David S.; Fahr, Abbas; Leemans, Dirk V.; McRae, Ken I.
2000-05-01
The economic drive towards using aircraft beyond their initial design life has created a great interest in damage-tolerance (DT) based maintenance. The DT approach relies on routine nondestructive inspections (NDI), and requires that the NDI performance to be quantified in terms probability of detection (POD) to determine the safe inspection intervals. The most common approach for determining NDI POD is to perform inspections on representative components or specimens simulating the actual parts. This approach is practical but can be very expensive. A more economical approach may be to use actual field inspection data to obtain POD. This approach is particularly attractive for airframe inspection techniques, since most airframe structures cannot be easily simulated. There are a number of difficulties with this approach: Firstly, there is usually a very limited amount of field data. This may require special statistical treatment. Secondly, crack growth data must exist to allow the estimation of flaw sizes at the inspection sites at inspection times before the flaws were found. These factors and others affect the confidence in the calculated POD, and must be quantified before POD data of this type can be used. In this work, data from full scale fatigue tests were analyzed, and methods of overcoming the problems of small sample sizes and crack growth data requirements were investigated.
The challenge of precise orbit determination for STSAT-2C using extremely sparse SLR data
NASA Astrophysics Data System (ADS)
Kim, Young-Rok; Park, Eunseo; Kucharski, Daniel; Lim, Hyung-Chul; Kim, Byoungsoo
2016-03-01
The Science and Technology Satellite (STSAT)-2C is the first Korean satellite equipped with a laser retro-reflector array for satellite laser ranging (SLR). SLR is the only on-board tracking source for precise orbit determination (POD) of STSAT-2C. However, POD for the STSAT-2C is a challenging issue, as the laser measurements of the satellite are extremely sparse, largely due to the inaccurate two-line element (TLE)-based orbit predictions used by the SLR tracking stations. In this study, POD for the STSAT-2C using extremely sparse SLR data is successfully implemented, and new laser-based orbit predictions are obtained. The NASA/GSFC GEODYN II software and seven-day arcs are used for the SLR data processing of two years of normal points from March 2013 to May 2015. To compensate for the extremely sparse laser tracking, the number of estimation parameters are minimized, and only the atmospheric drag coefficients are estimated with various intervals. The POD results show that the weighted root mean square (RMS) post-fit residuals are less than 10 m, and the 3D day boundaries vary from 30 m to 3 km. The average four-day orbit overlaps are less than 20/330/20 m for the radial/along-track/cross-track components. The quality of the new laser-based prediction is verified by SLR observations, and the SLR residuals show better results than those of previous TLE-based predictions. This study demonstrates that POD for the STSAT-2C can be successfully achieved against extreme sparseness of SLR data, and the results can deliver more accurate predictions.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Paulsson, Bjorn N.P.
2016-06-29
To address the critical site characterization and monitoring needs for Enhance Geothermal Systems (EGS) programs, US Department of Energy (DOE) awarded Paulsson, Inc. in 2011 a contract to design, build and test a high temperature fiber optic based ultra-large bandwidth clamped borehole seismic vector array capable of deploying a large number of 3C sensor pods suitable for deployment into high temperature and high pressure boreholes. Paulsson, Inc. has completed a design or a unique borehole seismic system consisting of a novel drill pipe based deployment system that includes a hydraulic clamping mechanism for the sensor pods, a new sensor podmore » design and most important – a unique fiber optic seismic vector sensor with technical specifications and capabilities that far exceed the state of the art seismic sensor technologies. These novel technologies were all applied to the new borehole seismic system. In combination these technologies will allow for the deployment of up to 1,000 3C sensor pods in vertical, deviated or horizontal wells. Laboratory tests of the fiber optic seismic vector sensors developed during this project have shown that the new borehole seismic sensor technology is capable of generating outstanding high vector fidelity data with extremely large bandwidth: 0.01 – 6,000 Hz. Field tests have shown that the system can record events at magnitudes much smaller than M-4.0 at frequencies over 2,000 Hz. The sensors have also proved to be about 100 times more sensitive than the regular coil geophones that are used in borehole seismic systems today. The fiber optic seismic sensors have furthermore been qualified to operate at temperatures over 300°C (572°F). The data telemetry fibers used for the seismic vector sensors in the system are also used to simultaneously record Distributed Temperature Sensor (DTS) and Distributed Acoustic Sensor (DAS) data allowing additional value added data to be recorded simultaneously with the seismic vector sensor data.« less
NASA Astrophysics Data System (ADS)
Gerosa, Giacomo; Fusaro, Lina; Monga, Robert; Finco, Angelo; Fares, Silvano; Manes, Fausto; Marzuoli, Riccardo
2015-07-01
Young plants of Holm oak (Quercus ilex) were exposed in non-limiting water conditions to four different levels of ozone (O3) concentrations in Open-Top Chambers during one growing season to evaluate biomass losses on roots, stems and leaves in relation to O3 exposure (AOT40) and phytotoxical ozone dose (POD1) absorbed. The exposure-effect and dose-effect relationships for the total biomass were statistically significant and indicated a reduction of 4% and 5.2% of the total biomass for each increase step of 10000 ppb h of AOT40 and 10 mmol m-2 of POD1, respectively. The results indicate a critical level for Holm oak protection of 7 mmol m-2 of POD1, which corresponds to 4% of total biomass reduction. The linear regressions based on the POD1 were significant for roots and stem biomass losses, but not significant for leaf biomass. The biomass loss rate at increasing POD1 was higher for roots than for stems and leaves, suggesting that stem growth under high levels of O3 is less affected than root growth. Because of the scarcity of data from the Mediterranean area, these results can be relevant for the O3 risk assessment models and for the definition of new O3 critical levels for forests in Europe.
A genome-wide SNP scan accelerates trait-regulatory genomic loci identification in chickpea
Kujur, Alice; Bajaj, Deepak; Upadhyaya, Hari D.; Das, Shouvik; Ranjan, Rajeev; Shree, Tanima; Saxena, Maneesha S.; Badoni, Saurabh; Kumar, Vinod; Tripathi, Shailesh; Gowda, C.L.L.; Sharma, Shivali; Singh, Sube; Tyagi, Akhilesh K.; Parida, Swarup K.
2015-01-01
We identified 44844 high-quality SNPs by sequencing 92 diverse chickpea accessions belonging to a seed and pod trait-specific association panel using reference genome- and de novo-based GBS (genotyping-by-sequencing) assays. A GWAS (genome-wide association study) in an association panel of 211, including the 92 sequenced accessions, identified 22 major genomic loci showing significant association (explaining 23–47% phenotypic variation) with pod and seed number/plant and 100-seed weight. Eighteen trait-regulatory major genomic loci underlying 13 robust QTLs were validated and mapped on an intra-specific genetic linkage map by QTL mapping. A combinatorial approach of GWAS, QTL mapping and gene haplotype-specific LD mapping and transcript profiling uncovered one superior haplotype and favourable natural allelic variants in the upstream regulatory region of a CesA-type cellulose synthase (Ca_Kabuli_CesA3) gene regulating high pod and seed number/plant (explaining 47% phenotypic variation) in chickpea. The up-regulation of this superior gene haplotype correlated with increased transcript expression of Ca_Kabuli_CesA3 gene in the pollen and pod of high pod/seed number accession, resulting in higher cellulose accumulation for normal pollen and pollen tube growth. A rapid combinatorial genome-wide SNP genotyping-based approach has potential to dissect complex quantitative agronomic traits and delineate trait-regulatory genomic loci (candidate genes) for genetic enhancement in crop plants, including chickpea. PMID:26058368
Pod of Ultrasonic Detection of Synthetic Hard Alpha Inclusions in Titanium Aircraft Engine Forgings
NASA Astrophysics Data System (ADS)
Thompson, R. B.; Meeker, W. Q.; Brasche, L. J. H.
2011-06-01
The probability of detection (POD) of inspection techniques is a key input to estimating the lives of structural components such as aircraft engines. This paper describes work conducted as a part of the development of POD curves for the ultrasonic detection of synthetic hard alpha (SHA) inclusions in titanium aircraft engine forgings. The sample upon which the POD curves are to be based contains four types of right circular SHAs that have been embedded in a representative titanium forging, as well as a number of flat bottomed holes (FBHs). The SHAs were of two sizes, ♯3 and ♯5, with each size including seeds with nominal nitrogen concentrations of both 3 and 17 wt. %. The FBHs included sizes of ♯1, ♯3, and ♯5. This discreteness of the data poses a number of challenges to standard processes for determining POD. For example, at each concentration of nitrogen, there are only two sizes, with 10 inspection opportunities each. Fully empirical, standard methodologies such as â versus a provide less than an ideal framework for such an analysis. For example, there is no way to describe the beam limiting effect whereby the signal no longer increases the flaw grows larger than the beam, one can only determine POD at the two concentration levels present in the block, and confidence bounds tend to be broad because of the limited data available for each case. In this paper, we will describe strategies involving the use of physics-based models to overcome these difficulties by allowing the data from all reflectors to be analyzed by a single statistical model. Included will be a discussion of the development of the physics-based model, its comparison to the experimental data (obtained at multiple sites with multiple operators) and its implications regarding the statistical analysis, whose details will be given in a separate article by Li et al. in this volume.
NASA Astrophysics Data System (ADS)
Oware, E. K.; Moysey, S. M.
2016-12-01
Regularization stabilizes the geophysical imaging problem resulting from sparse and noisy measurements that render solutions unstable and non-unique. Conventional regularization constraints are, however, independent of the physics of the underlying process and often produce smoothed-out tomograms with mass underestimation. Cascaded time-lapse (CTL) is a widely used reconstruction technique for monitoring wherein a tomogram obtained from the background dataset is employed as starting model for the inversion of subsequent time-lapse datasets. In contrast, a proper orthogonal decomposition (POD)-constrained inversion framework enforces physics-based regularization based upon prior understanding of the expected evolution of state variables. The physics-based constraints are represented in the form of POD basis vectors. The basis vectors are constructed from numerically generated training images (TIs) that mimic the desired process. The target can be reconstructed from a small number of selected basis vectors, hence, there is a reduction in the number of inversion parameters compared to the full dimensional space. The inversion involves finding the optimal combination of the selected basis vectors conditioned on the geophysical measurements. We apply the algorithm to 2-D lab-scale saline transport experiments with electrical resistivity (ER) monitoring. We consider two transport scenarios with one and two mass injection points evolving into unimodal and bimodal plume morphologies, respectively. The unimodal plume is consistent with the assumptions underlying the generation of the TIs, whereas bimodality in plume morphology was not conceptualized. We compare difference tomograms retrieved from POD with those obtained from CTL. Qualitative comparisons of the difference tomograms with images of their corresponding dye plumes suggest that POD recovered more compact plumes in contrast to those of CTL. While mass recovery generally deteriorated with increasing number of time-steps, POD outperformed CTL in terms of mass recovery accuracy rates. POD is computationally superior requiring only 2.5 mins to complete each inversion compared to 3 hours for CTL to do the same.
Structural response of transport airplanes in crash situations
NASA Technical Reports Server (NTRS)
Thomson, R. G.; Caiafa, C.
1983-01-01
This report highlights the results of contractural studies of transport accident data undertaken in a joint research program sponsored by the FAA and NASA. From these accident data studies it was concluded that the greatest potential for improved transport crashworthiness is in the reduction of fire related fatalities. Accident data pertaining to fuselage integrity, main landing gear collapse, fuel tank rupture, wing breaks, tearing of tank lower surfaces, and engine pod scrubbing are discussed. In those accidents where the energy absorbing protective capability of the fuselage structure is expended and the airplane experiences major structural damage, trauma caused fatalities are also discussed. The dynamic performance of current seat/restraint systems are examined but it is concluded that the accident data does not adequately define the relationship between occupant response and the dynamic interaction with the seat, floor and fuselage structure.
Vertical Stabilizer and OMS pods from the aft FD window during STS-123 mission
2008-03-11
S123-E-005073 (11 Mar. 2008) --- This view out the aft windows on Endeavour's flight deck was one of a series of images recorded by the STS-123 crewmembers during their first full day in space. The end of the Canadian-built remote manipulator system's robot arm (right edge) along with the shuttle's vertical stabilizer and its two orbital maneuvering system (OMS) pods are visible. A heavily cloud-covered area of Earth fills the top half of the frame.
Precise science orbits for the Swarm satellite constellation
NASA Astrophysics Data System (ADS)
van den IJssel, Jose; Encarnação, João; Doornbos, Eelco; Visser, Pieter
2015-09-01
The European Space Agency (ESA) Swarm mission was launched on 22 November 2013 to study the dynamics of the Earth's magnetic field and its interaction with the Earth system. The mission consists of three identical satellites, flying in carefully selected near polar orbits. Two satellites fly almost side-by-side at an initial altitude of about 480 km, and will descend due to drag to around 300 km during the mission lifetime. The third satellite was placed in a higher orbit of about 530 km altitude, and therefore descends much more slowly. To geolocate the Swarm observations, each satellite is equipped with an 8-channel, dual-frequency GPS receiver for Precise Orbit Determination (POD). Onboard laser retroreflectors provide the opportunity to validate the orbits computed from the GPS observations using Satellite Laser Ranging (SLR) data. Precise Science Orbits (PSOs) for the Swarm satellites are computed by the Faculty of Aerospace Engineering at Delft University of Technology in the framework of the Swarm Satellite Constellation Application and Research Facility (SCARF). The PSO product consists of both a reduced-dynamic and a kinematic orbit solution. After a short description of the Swarm GPS data characteristics, the adopted POD strategy for both orbit types is explained and first PSO results from more than one year of Swarm GPS data are presented. Independent SLR validation shows that the reduced-dynamic Swarm PSOs have an accuracy of better than 2 cm, while the kinematic orbits have a slightly reduced accuracy of about 4-5 cm. Orbit comparisons indicate that the consistency between the reduced-dynamic and kinematic Swarm PSO for most parts of the Earth is at the 4-5 cm level. Close to the geomagnetic poles and along the geomagnetic equator, however, the kinematic orbits show larger errors, which are probably due to ionospheric scintillations that affect the Swarm GPS receivers over these areas.
NASA Astrophysics Data System (ADS)
Raghupathy, Arun; Ghia, Karman; Ghia, Urmila
2008-11-01
Compact Thermal Models (CTM) to represent IC packages has been traditionally developed using the DELPHI-based (DEvelopment of Libraries of PHysical models for an Integrated design) methodology. The drawbacks of this method are presented, and an alternative method is proposed. A reduced-order model that provides the complete thermal information accurately with less computational resources can be effectively used in system level simulations. Proper Orthogonal Decomposition (POD), a statistical method, can be used to reduce the order of the degree of freedom or variables of the computations for such a problem. POD along with the Galerkin projection allows us to create reduced-order models that reproduce the characteristics of the system with a considerable reduction in computational resources while maintaining a high level of accuracy. The goal of this work is to show that this method can be applied to obtain a boundary condition independent reduced-order thermal model for complex components. The methodology is applied to the 1D transient heat equation.
NASA Astrophysics Data System (ADS)
Frearson, N.
2012-12-01
Columbia University in New York is developing a geophysical instrumentation package that is capable of monitoring dynamic en-glacial and sub-glacial processes. The instruments include a Riegl Scanning Laser for precise measurements of the ice surface elevation, Stereo photogrammetry from a high sensitivity (~20mK) Infra-Red camera and a high resolution Visible Imaging camera (2456 x 2058 pixels) to document fine scale ice temperature changes and surface features, near surface ice penetrating radar and an ice depth measuring radar that can be used to study interior and basal processes of ice shelves, glaciers, ice streams and ice-sheets. All instrument data sets will be time-tagged and geo-referenced using precision GPS satellite data. Aircraft orientation will be corrected using inertial measurement technology integrated into the pod. This instrumentation will be flown across some of the planets largest outlet glaciers in Antarctica and Greenland. However, a key aspect of the design is that at the conclusion of the program, the Pod, Deployment Arm, Data Acquisition and Power and Environmental Management system will become available for use by the science community at large to install their own instruments onto. It will also be possible to mount the Icepod onto other airframes. The sensor system will become part of a research facility operated for the science community, and data will be maintained at and made available through a Polar Data Center.
Zhang, Wenxu; Mao, Peisheng; Li, Yuan; Wang, Mingya; Xia, Fangshan; Wang, Hui
2017-02-07
The distribution of carbon from a branch setting pod in alfalfa was investigated during the seed development of seeds to determine the relative contribution of pod and leaf photoassimilates to the total C balance and to investigate the partitioning of these photoassimilates to other plant organs. A 13 Clabeling procedure was used to label C photoassimilates of pods and leaves in alfalfa, and the Δ 13 C values of a pod, leaves, a section of stem and roots were measured during seed development on day 10, 15, 20 and 25 after labeling of the pod. The results showed that the alfalfa pod had photosynthetic capacity early in the development of seeds, and that pod photosynthesis could provide carbon to alfalfa organs including seeds, pods, leaves, stems and roots, in addition to leaf photosynthesis. Photosynthesis in the pod affected the total C balance of the alfalfa branch with the redistribution of a portion of pod assimilates to other plant organs. The assimilated 13 C of the pod was used for the growth requirements of plant seeds and pods. The requirements for assimilated C came primarily from the young pod in early seed development, with later requirements provided primarily from the leaf.
IcePod - A versatile Science Platform for the New York Air National Guard's LC-130 Aircraft
NASA Astrophysics Data System (ADS)
Frearson, N.; Bell, R. E.; Zappa, C. J.
2011-12-01
The ICEPOD program is a five-year effort to develop an ice imaging system mounted on New York Air National Guard (NYANG) LC-130 aircraft to map the surface and sub-surface topography of ice sheets, ice streams and outlet glaciers for the NSF Major Research Instrumentation program. The project is funded by the American Recovery and Reinvestment Act. The fundamental goal of the ICEPOD program is to develop an instrumentation package that can capture the dynamics of the changing polar regions, focusing on ice and ocean systems. The vision is that this instrumentation will be operated both on routine flights of the NYANG in the polar regions, such as on missions between McMurdo and South Pole Station, and on targeted science missions, from mapping sea ice and outlet glaciers such as those surrounding Ross Island or Greenland to quantifying the drainage systems from large subglacial lakes in East Antarctica. It is a key aspect of the design that at the conclusion of this program, the Pod, Deployment Arm and Data Acquisition and Management system will become available for use by the science community at large to install their own instruments onto. The science requirements for the primary instruments in the Icepod program have been defined and can be viewed on-line at www.ldeo.columbia.edu/icepod. As a consequence, the instrumentation will consist of a scanning laser for precise measurements of the ice surface, stereo-photogrammetry from both visible and infrared imaging cameras to document the ice surface and temperature, a VHF coherent, pulsed radar to recover ice thickness and constrain the distribution of water at the ice sheet bed and an L-band radar to measure surface accumulation or sea-ice thickness. All instrument data sets will be time-tagged and geo-referenced by recording precision GPS satellite data integrated with inertial measurement technology integrated into the pod. There will also be two operational modes - a low altitude flight mode that will optimize the imaging systems and a high altitude flight mode that will facilitate wider use of the instrumentation suite on routine NYANG support missions. Proposals for new observations are welcome. The sensor system will become a research facility operated for the science community, and data will be maintained at and provided through a polar data center.
Chen, Lantao; Sun, Lixin; Lang, Yaoguo; Wu, Jun; Yao, Lei; Ning, Jinfeng; Zhang, Jinfeng; Xu, Shidong
2016-07-11
Our aim was to investigate the influence of FTS on human cellular and humoral immunity using a randomized controlled clinical study in esophageal cancer patients. Between October 2013 and December 2014, 276 patients with esophageal cancer in our department were enrolled in the study. The patients were randomized into two groups: FTS pathway group and conventional pathway group. The postoperative hospital stay, hospitalization expenditure, and postoperative complications were recorded. The markers of inflammatory and immune function were measured before operation as well as on the 1st, 3rd, and 7th postoperative days (POD), including serum level of interleukin-6 (IL-6), C-reactive protein (CRP), serum globulin, immunoglobulin G (IgG), immunoglobulin M (IgM), immunoglobulin A (IgA) and lymphocyte subpopulations (CD3 lymphocytes, CD4 lymphocytes, CD8 lymphocytes and the CD4/CD8 ratio) in the patients between the two groups. In all, 260 patients completed the study: 128 in the FTS group and 132 in the conventional group. We found implementation of FTS pathway decreases postoperative length of stay and hospital charges (P < 0.05). In addition, inflammatory reactions, based on IL-6 and CRP levels, were less intense following FTS pathway compared to conventional pathway on POD1 and POD3 (P < 0.05). On POD1 and POD3, the levels of IgG, IgA, CD3 lymphocytes, CD4 lymphocytes and the CD4/CD8 ratio in FTS group were significantly higher than those in control group (All P < 0.05). However, there were no differences in the level of IgM and CD8 lymphocytes between the two groups. FTS improves postoperative clinical recovery and effectively inhibited release of inflammatory factors via the immune system after esophagectomy for esophageal cancer. ChiCTR-TRC-13003562 , the date of registration: August 29, 2013.
Twardy, Vanessa; Becker, Felix; Geyer, Christiane; Schwegmann, Katrin; Mohr, Annika; Faust, Andreas
2018-01-01
Background Disturbance of intestinal wound closure leads to insufficient anastomotic healing and is associated with considerable morbidity following colorectal resections. Matrix metalloproteinases (MMPs) play a crucial role in regulation of wound closure. Here fluorescence endoscopy was evaluated for assessment of MMP-2/-9 expression during failed intestinal anastomotic healing. Methods Distal colonic anastomoses were performed as a model for disturbed healing in 36 Balb/c mice. Healing was evaluated endoscopically, macroscopically, and histologically after 1, 3 and 5 days. For detection of MMP-2/-9 expression fluorescence endoscopy (FE) was used following i.v.-administration of a Cy5.5-labeled MMP-2/-9 specific tracer. FE was complemented by quantification of the fluorescence signal using the MS-FX PRO Optical Imaging System. An overall leakage score was calculated and correlated with the results of FE. Results With increasing incidence of anastomotic leakage from POD1 (17%) to POD5 (83%) the uptake of the MMP tracer gradually increased (signal-to-noise ratio (SNR), POD1: 17.91 ± 1.251 vs. POD3: 30.56 ± 3.03 vs. POD5: 44.8 ± 4.473, P<0.0001). Mice with defective anastomotic healing showed significantly higher uptake compared to non-defective (SNR: 37.37± 3.63 vs. 26.16± 3.635, P = 0.0369). White light endoscopy and FE allowed evaluation of anastomotic healing and visualization of mucosal MMPs in vivo. Using FE based detection of MMPs in the anastomosis, an overall positive predictive value of 71.4% and negative predictive value of 66.6% was calculated for detection of anastomotic leakage. Conclusion During disturbed anastomotic healing increased expression of MMP-2/-9 was observed in the anastomotic tissue. Fluorescence endoscopy for detection of MMP-2/-9 during the healing process might be a promising tool for early identification of anastomotic leakage. PMID:29566031
Neumann, Philipp-Alexander; Twardy, Vanessa; Becker, Felix; Geyer, Christiane; Schwegmann, Katrin; Mohr, Annika; Faust, Andreas; Lenz, Philipp; Rijcken, Emile
2018-01-01
Disturbance of intestinal wound closure leads to insufficient anastomotic healing and is associated with considerable morbidity following colorectal resections. Matrix metalloproteinases (MMPs) play a crucial role in regulation of wound closure. Here fluorescence endoscopy was evaluated for assessment of MMP-2/-9 expression during failed intestinal anastomotic healing. Distal colonic anastomoses were performed as a model for disturbed healing in 36 Balb/c mice. Healing was evaluated endoscopically, macroscopically, and histologically after 1, 3 and 5 days. For detection of MMP-2/-9 expression fluorescence endoscopy (FE) was used following i.v.-administration of a Cy5.5-labeled MMP-2/-9 specific tracer. FE was complemented by quantification of the fluorescence signal using the MS-FX PRO Optical Imaging System. An overall leakage score was calculated and correlated with the results of FE. With increasing incidence of anastomotic leakage from POD1 (17%) to POD5 (83%) the uptake of the MMP tracer gradually increased (signal-to-noise ratio (SNR), POD1: 17.91 ± 1.251 vs. POD3: 30.56 ± 3.03 vs. POD5: 44.8 ± 4.473, P<0.0001). Mice with defective anastomotic healing showed significantly higher uptake compared to non-defective (SNR: 37.37± 3.63 vs. 26.16± 3.635, P = 0.0369). White light endoscopy and FE allowed evaluation of anastomotic healing and visualization of mucosal MMPs in vivo. Using FE based detection of MMPs in the anastomosis, an overall positive predictive value of 71.4% and negative predictive value of 66.6% was calculated for detection of anastomotic leakage. During disturbed anastomotic healing increased expression of MMP-2/-9 was observed in the anastomotic tissue. Fluorescence endoscopy for detection of MMP-2/-9 during the healing process might be a promising tool for early identification of anastomotic leakage.
Hanada, Rogério Eiji; Pomella, Alan William V; Costa, Heron Salazar; Bezerra, José Luiz; Loguercio, Leandro L; Pereira, José O
2010-01-01
The endophytic niches of plants are a rich source of microbes that can directly and indirectly promote plant protection, growth and development. The diversity of culturable endophytic fungi from stems and branches of Theobroma cacao (cacao) and Theobroma grandiflorum (cupuaçu) trees growing in the Amazon region of Brazil was assessed. The collection of fungal endophytic isolates obtained was applied in field experiments to evaluate their potential as biocontrol agents against Phytophthora palmivora, the causal agent of the black-pod rot disease of cacao, one of the most important pathogens in cocoa-producing regions worldwide. The isolated endophytic fungi from 60 traditional, farmer-planted, healthy cacao and 10 cupuaçu plants were cultured in PDA under conditions inducing sporulation. Isolates were classified based upon the morphological characteristics of their cultures and reproductive structures. Spore suspensions from a total of 103 isolates that could be classified at least up to genus level were tested against P. palmivora in pods attached to cacao trees in the field. Results indicated that ∼70% of isolates showed biocontrol effects to a certain extent, suggesting that culturable endophytic fungal biodiversity in this system is of a mostly mutualistic type of interaction with the host. Eight isolates from genera Trichoderma (reference isolate), Pestalotiopsis, Curvularia, Tolypocladium and Fusarium showed the highest level of activity against the pathogen, and were further characterized. All demonstrated their endophytic nature by colonizing axenic cacao plantlets, and confirmed their biocontrol activity on attached pods trials by showing significant decrease in disease severity in relation to the positive control. None, however, showed detectable growth-promotion effects. Aspects related to endophytic biodiversity and host-pathogen-endophyte interactions in the environment of this study were discussed on the context of developing sustainable strategies for biological control of black-pod rot of cacao. Copyright © 2010 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.
Huang, Shih-Hao; Wei, Lu-Shiuan; Chu, Hsiao-Tzu; Jiang, Yeu-Long
2013-01-01
This paper describes a light-addressed electrolytic system used to perform an electrodeposition of enzyme-entrapped chitosan membranes for multiplexed enzyme-based bioassays using a digital micromirror device (DMD). In this system, a patterned light illumination is projected onto a photoconductive substrate serving as a photo-cathode to electrolytically produce hydroxide ions, which leads to an increased pH gradient. The high pH generated at the cathode can cause a local gelation of chitosan through sol-gel transition. By controlling the illumination pattern on the DMD, a light-addressed electrodeposition of chitosan membranes with different shapes and sizes, as well as multiplexed micropatterning, was performed. The effect of the illumination time of the light pattern on the dimensional resolution of chitosan membrane formation was examined experimentally. Moreover, multiplexed enzyme-based bioassay of enzyme-entrapped chitosan membranes was also successfully demonstrated through the electrodeposition of the chitosan membranes with various shapes/sizes and entrapping different enzymes. As a model experiment, glucose and ethanol were simultaneously detected in a single detection chamber without cross-talk using shape-coded chitosan membranes entrapped with glucose oxidase (GOX), peroxidase (POD), and Amplex Red (AmR) or alcohol oxidase (AOX), POD, and AmR by using same fluorescence indicator (AmR). PMID:23959236
Huang, Shih-Hao; Wei, Lu-Shiuan; Chu, Hsiao-Tzu; Jiang, Yeu-Long
2013-08-16
This paper describes a light-addressed electrolytic system used to perform an electrodeposition of enzyme-entrapped chitosan membranes for multiplexed enzyme-based bioassays using a digital micromirror device (DMD). In this system, a patterned light illumination is projected onto a photoconductive substrate serving as a photo-cathode to electrolytically produce hydroxide ions, which leads to an increased pH gradient. The high pH generated at the cathode can cause a local gelation of chitosan through sol-gel transition. By controlling the illumination pattern on the DMD, a light-addressed electrodeposition of chitosan membranes with different shapes and sizes, as well as multiplexed micropatterning, was performed. The effect of the illumination time of the light pattern on the dimensional resolution of chitosan membrane formation was examined experimentally. Moreover, multiplexed enzyme-based bioassay of enzyme-entrapped chitosan membranes was also successfully demonstrated through the electrodeposition of the chitosan membranes with various shapes/sizes and entrapping different enzymes. As a model experiment, glucose and ethanol were simultaneously detected in a single detection chamber without cross-talk using shape-coded chitosan membranes entrapped with glucose oxidase (GOX), peroxidase (POD), and Amplex Red (AmR) or alcohol oxidase (AOX), POD, and AmR by using same fluorescence indicator (AmR).
NASA Astrophysics Data System (ADS)
Deem, Eric; Cattafesta, Louis; Zhang, Hao; Rowley, Clancy
2016-11-01
Closed-loop control of flow separation requires the spatio-temporal states of the flow to be fed back through the controller in real time. Previously, static and dynamic estimation methods have been employed that provide reduced-order model estimates of the POD-coefficients of the flow velocity using surface pressure measurements. However, this requires a "learning" dataset a priori. This approach is effective as long as the dynamics during control do not stray from the learning dataset. Since only a few dynamical features are required for feedback control of flow separation, many of the details provided by full-field snapshots are superfluous. This motivates a state-observation technique that extracts key dynamical features directly from surface pressure, without requiring PIV snapshots. The results of identifying DMD modes of separated flow through an array of surface pressure sensors in real-time are presented. This is accomplished by employing streaming DMD "on the fly" to surface pressure snapshots. These modal characteristics exhibit striking similarities to those extracted from PIV data and the pressure field obtained via solving Poisson's equation. Progress towards closed-loop separation control based on the dynamic modes of surface pressure will be discussed. Supported by AFOSR Grant FA9550-14-1-0289.
2011-02-01
VANDENBERG AIR FORCE BASE, Calif. -- At Vandenberg Air Force Base in California, a technician installs a bracket on a Poly Picosatellite Orbital Deployer, or P-POD, container. The bracket is a connection interface between the P-POD and the Taurus rocket. The P-POD will hold three CubeSats or tiny satellites, designed and created by university and college students that will be carried on the Taurus rocket along with the Glory spacecraft. The Orbital Sciences Corp. Taurus XL rocket will carry NASA's Glory spacecraft into low Earth orbit. Once Glory reaches orbit, it will collect data on the properties of aerosols and black carbon. It also will help scientists understand how the sun's irradiance affects Earth's climate. Launch is scheduled for 5:09 a.m. EST Feb. 23. For information, visit www.nasa.gov/glory. Photo credit: NASA/Randy Beaudoin, VAFB
2011-02-01
VANDENBERG AIR FORCE BASE, Calif. -- At Vandenberg Air Force Base in California, a Poly Picosatellite Orbital Deployer, or P-POD, container is imaged here with the bracket interface installed. The bracket is a connection interface between the P-POD and the Taurus rocket. The P-POD will hold three CubeSats or tiny satellites, designed and created by university and college students that will be carried on the Taurus rocket along with the Glory spacecraft. The Orbital Sciences Corp. Taurus XL rocket will carry NASA's Glory spacecraft into low Earth orbit. Once Glory reaches orbit, it will collect data on the properties of aerosols and black carbon. It also will help scientists understand how the sun's irradiance affects Earth's climate. Launch is scheduled for 5:09 a.m. EST Feb. 23. For information, visit www.nasa.gov/glory. Photo credit: NASA/Randy Beaudoin,VAFB
2011-02-01
VANDENBERG AIR FORCE BASE, Calif. -- At Vandenberg Air Force Base in California, a Poly Picosatellite Orbital Deployer, or P-POD, container is imaged here with the bracket interface installed. The bracket is a connection interface between the P-POD and the Taurus rocket. The P-POD will hold three CubeSats or tiny satellites, designed and created by university and college students that will be carried on the Taurus rocket along with the Glory spacecraft. The Orbital Sciences Corp. Taurus XL rocket will carry NASA's Glory spacecraft into low Earth orbit. Once Glory reaches orbit, it will collect data on the properties of aerosols and black carbon. It also will help scientists understand how the sun's irradiance affects Earth's climate. Launch is scheduled for 5:09 a.m. EST Feb. 23. For information, visit www.nasa.gov/glory. Photo credit: NASA/Randy Beaudoin, VAFB
Position and orientation tracking system
Burks, Barry L.; DePiero, Fred W.; Armstrong, Gary A.; Jansen, John F.; Muller, Richard C.; Gee, Timothy F.
1998-01-01
A position and orientation tracking system presents a laser scanning appaus having two measurement pods, a control station, and a detector array. The measurement pods can be mounted in the dome of a radioactive waste storage silo. Each measurement pod includes dual orthogonal laser scanner subsystems. The first laser scanner subsystem is oriented to emit a first line laser in the pan direction. The second laser scanner is oriented to emit a second line laser in the tilt direction. Both emitted line lasers scan planes across the radioactive waste surface to encounter the detector array mounted on a target robotic vehicle. The angles of incidence of the planes with the detector array are recorded by the control station. Combining measurements describing each of the four planes provides data for a closed form solution of the algebraic transform describing the position and orientation of the target robotic vehicle.
Position and orientation tracking system
Burks, B.L.; DePiero, F.W.; Armstrong, G.A.; Jansen, J.F.; Muller, R.C.; Gee, T.F.
1998-05-05
A position and orientation tracking system presents a laser scanning apparatus having two measurement pods, a control station, and a detector array. The measurement pods can be mounted in the dome of a radioactive waste storage silo. Each measurement pod includes dual orthogonal laser scanner subsystems. The first laser scanner subsystem is oriented to emit a first line laser in the pan direction. The second laser scanner is oriented to emit a second line laser in the tilt direction. Both emitted line lasers scan planes across the radioactive waste surface to encounter the detector array mounted on a target robotic vehicle. The angles of incidence of the planes with the detector array are recorded by the control station. Combining measurements describing each of the four planes provides data for a closed form solution of the algebraic transform describing the position and orientation of the target robotic vehicle. 14 figs.
Sung, Nayoung; Kwak-Kim, Joanne; Koo, H S; Yang, K M
2016-09-01
To investigate hCG-β level on postovulatory day (POD) 12 and its fold increase as predictors for pregnancy outcome after in vitro fertilization (IVF) cycles. A retrospective cohort study was performed in total 1408 fresh and 598 frozen cycles between November 2008 and October 2011, which resulted in biochemical pregnancy, early pregnancy loss, or live birth of singleton pregnancy. The serum hCG-β levels of POD 12 and 14 were compared among biochemical pregnancy, early pregnancy loss, and live birth groups. The cutoff values of POD 12 and 14 hCG-β levels and the degree of hCG-β increase from POD 12 to 14 were determined for each pregnancy outcome. POD 12 and 14 hCG-β levels stratified based on pregnancy outcomes were significantly different among the biochemical pregnancy, early pregnancy loss, and live birth in both fresh and frozen cycles. Serum hCG-β levels of POD 12 and 14 and the fold increase of hCG-β levels from POD 12 to 14 significantly predict pregnancy outcomes after fresh and frozen cycles. Among these, the cutoff value of POD 14 hCG-β had the highest sensitivity and positive predictive value (PPV). In fresh cycles, the cutoff values of POD 12 and 14 serum hCG-β levels for clinical pregnancies were 30.2 mIU/mL (sensitivity 81.3 %, specificity 79.6 %, and PPV 92.3 %) and 70.5 mIU/mL (sensitivity 88.4 %, specificity 85.2 %, and PPV 94.7 %). In pregnancies with POD 12 serum hCG-β levels ≥30.2 mIU/mL, the cutoff level of increase of hCG-β for clinical pregnancy was 2.56 (sensitivity 73.6 %, specificity 72.4 %, and PPV 97.8 %). Sequential application of cutoff values such as POD 12 hCG-β and fold increase of hCG-β improved predictability of pregnancy outcome as compared with that of POD 12 hCG-β alone. The cutoff values of POD 12 and 14 serum hCG-β levels for live birth were 40.5 mIU/mL (sensitivity 75.2 %, specificity 72.6 %, PPV 78.9 %) and 104.5 mIU/mL (sensitivity 80.3 %, specificity 74.1 %, PPV 80.8 %). In the frozen cycles, the cutoff values of POD 12 and 14 serum hCG-β level for clinical pregnancy were 31.5 IU/L (sensitivity 80.4 %, specificity 71.1 % and PPV 90 %) and 43.5 mIU/mL (sensitivity 72.6 %, specificity 71.7 %, PPV 77.2 %). In pregnancies with POD 12 serum hCG-β level ≥31.5 mIU/mL, the cutoff value for fold increase of hCG-β was 2.38 for clinical pregnancy (sensitivity 81.6 %, specificity 71.4 % and PPV 87.9 %). The cutoff values of POD 12 and 14 for live birth were 43.5 mIU/mL (sensitivity 72.6 %, specificity 71.7 %, PPV 77.2 %) and 101.6 mIU/mL (sensitivity 79.6 %, specificity 71.1 %, PPV 78.4 %). Sequential application of cutoff values for POD 12 hCG-β level and fold increase of hCG-β significantly increased PPV for live birth but not clinical pregnancy in frozen cycles. Early prediction of pregnancy outcome by using POD 12 and 14 cutoff levels and sequential application of cutoff value of fold increase could provide appropriate reference to health care providers to initiate earlier management of high-risk pregnancies and precise follow-up of abnormal pregnancies.
Tanaka, Seiya; Ario, Nobuyuki; Nakagawa, Andressa Camila Seiko; Tomita, Yuki; Murayama, Naoki; Taniguchi, Takatoshi; Hamaoka, Norimitsu; Iwaya-Inoue, Mari; Ishibashi, Yushi
2017-06-03
Soybean pods are located at the nodes, where they are in the shadow, whereas cowpea pods are located outside of the leaves and are exposed to sunlight. To compare the effects of light quality on pod growth in soybean and cowpea, we measured the length of pods treated with white, blue, red or far-red light. In both species, pods elongated faster during the dark period than during the light period in all light treatments except red light treatment in cowpea. Red light significantly suppressed pod elongation in soybean during the dark and light periods. On the other hand, the elongation of cowpea pods treated with red light markedly promoted during the light period. These results suggested that the difference in the pod set sites between soybean and cowpea might account for the difference in their red light responses for pod growth.
Patterns in place of cancer death in the State of Qatar: a population-based study.
Mohsen, Hassan; Haddad, Pascale; Allam, Ayman; Hassan, Azza
2014-01-01
International studies show that most people prefer to die at home; however, hospitals remain the most common place of death (PoD). This study aims to investigate the patterns in PoD and the associated factors, which are crucial for end-of-life cancer care enhancement. This retrospective, population-based study analyzed all registered cancer deaths in Qatar between January 1, 2006 and December 31, 2012 (n = 1,224). The main outcome measures were patient characteristics: age, gender, nationality, cancer diagnosis, year of death, and PoD. Time trends for age-standardized proportions of death in individual PoDs were evaluated using chi-square analysis. Odds ratio (OR) were determined for variables associated with the most preferred (acute palliative care unit [APCU] and hematology/oncology ward) versus least preferred (ICU and general medicine ward) PoDs in Qatar, stratified by nationality. The hematology/oncology ward was the most common PoD (32.4%; 95% CI 26.7-35.3%) followed by ICU (31.4%; 95% CI 28.7-34.3%), APCU (26.9%; 95% CI 24.3-29.6%), and general medicine ward (9.2%; 95% CI 7.6-11.1%). APCU trended upward (+0.057/year; p<0.001), while the hematology/oncology ward trended downward (-0.055/year; p<0.001). No statistically significant changes occurred in the other PoDs; home deaths remained low (0.4%; 95% Cl 0.38-0.42). Qataris who died from liver cancer (OR 0.23) and aged 65 or older (OR 0.64) were less likely to die in the APCU or hematology/oncology ward (p<0.05). Non-Qataris who died from pancreatic cancer (OR 3.12) and female (OR 2.05) were more likely to die in the APCU or hematology/oncology ward (p<0.05). Both Qataris and non-Qataris who died from hematologic malignancy (OR 0.18 and 0.41, respectively) were more likely to die in the ICU or general medicine ward (p<0.05). A high percentage of cancer deaths in Qatar occur in hospital. As home was the preferred PoD for most people, effective home care and hospice programs are needed to improve end-of-life cancer care.
Patterns in Place of Cancer Death in the State of Qatar: A Population-Based Study
Mohsen, Hassan; Haddad, Pascale; Allam, Ayman; Hassan, Azza
2014-01-01
Background International studies show that most people prefer to die at home; however, hospitals remain the most common place of death (PoD). This study aims to investigate the patterns in PoD and the associated factors, which are crucial for end-of-life cancer care enhancement. Method This retrospective, population-based study analyzed all registered cancer deaths in Qatar between January 1, 2006 and December 31, 2012 (n = 1,224). The main outcome measures were patient characteristics: age, gender, nationality, cancer diagnosis, year of death, and PoD. Time trends for age-standardized proportions of death in individual PoDs were evaluated using chi-square analysis. Odds ratio (OR) were determined for variables associated with the most preferred (acute palliative care unit [APCU] and hematology/oncology ward) versus least preferred (ICU and general medicine ward) PoDs in Qatar, stratified by nationality. Results The hematology/oncology ward was the most common PoD (32.4%; 95% CI 26.7–35.3%) followed by ICU (31.4%; 95% CI 28.7–34.3%), APCU (26.9%; 95% CI 24.3–29.6%), and general medicine ward (9.2%; 95% CI 7.6–11.1%). APCU trended upward (+0.057/year; p<0.001), while the hematology/oncology ward trended downward (−0.055/year; p<0.001). No statistically significant changes occurred in the other PoDs; home deaths remained low (0.4%; 95% Cl 0.38–0.42). Qataris who died from liver cancer (OR 0.23) and aged 65 or older (OR 0.64) were less likely to die in the APCU or hematology/oncology ward (p<0.05). Non-Qataris who died from pancreatic cancer (OR 3.12) and female (OR 2.05) were more likely to die in the APCU or hematology/oncology ward (p<0.05). Both Qataris and non-Qataris who died from hematologic malignancy (OR 0.18 and 0.41, respectively) were more likely to die in the ICU or general medicine ward (p<0.05). Conclusion A high percentage of cancer deaths in Qatar occur in hospital. As home was the preferred PoD for most people, effective home care and hospice programs are needed to improve end-of-life cancer care. PMID:25536076
Effects of Aluminum Stress on Protective Enzyme Activity in Tie Guanyin leaves
NASA Astrophysics Data System (ADS)
Sun, JingWei; Du, NaiChen; Zhang, YunFeng
2018-01-01
The experiment was adopted to study the change of SOD, CAT and POD activity of Tie guanyin (new leaf and old leaf blade of different concentrations of aluminum stress; in this paper, 0 (CK), 40, 200, four gradients of 400mg/L concentration of Al3+ in acidic conditions, Tieguanyin tea leaf SOD, cat and POD activity changes. The results showed that high concentrations of aluminum stress on antioxidant enzyme system activity cannot continue to increase; at the same time showed that SOD is sensitive to aluminum toxicity concentration change, its sensitivity is higher than CAT and POD, SOD and CAT activity and the aging and decline of plant There was a positive correlation.
NASA Astrophysics Data System (ADS)
Hillenbrand, Christopher F.; Barron, Thomas D.; Nugent, David M.
1995-03-01
A submarine trails one fiber optic cable and an undersea vehicle is controlled by this first cable. A missile/torpedo trails a second cable that is to be coupled to the first cable. The second cable has a segment suspended vertically underwater between a buoyant pod and a sea anchor type buoy. The undersea vehicle, or Autonomous Undersea Vehicle, (AUV) hunts for the pod by conventional homing means. A forked cable pickup device in the nose of the AUV captures the suspended cable segment directing it into a slot so a male socket in the underside of the pod mates with a female socket in the slot.
NASA Astrophysics Data System (ADS)
Dang, Van Tuan; Lafon, Pascal; Labergere, Carl
2017-10-01
In this work, a combination of Proper Orthogonal Decomposition (POD) and Radial Basis Function (RBF) is proposed to build a surrogate model based on the Benchmark Springback 3D bending from the Numisheet2011 congress. The influence of the two design parameters, the geometrical parameter of the die radius and the process parameter of the blank holder force, on the springback of the sheet after a stamping operation is analyzed. The classical Design of Experience (DoE) uses Full Factorial to design the parameter space with sample points as input data for finite element method (FEM) numerical simulation of the sheet metal stamping process. The basic idea is to consider the design parameters as additional dimensions for the solution of the displacement fields. The order of the resultant high-fidelity model is reduced through the use of POD method which performs model space reduction and results in the basis functions of the low order model. Specifically, the snapshot method is used in our work, in which the basis functions is derived from snapshot deviation of the matrix of the final displacements fields of the FEM numerical simulation. The obtained basis functions are then used to determine the POD coefficients and RBF is used for the interpolation of these POD coefficients over the parameter space. Finally, the presented POD-RBF approach which is used for shape optimization can be performed with high accuracy.
PodNet, a protein-protein interaction network of the podocyte.
Warsow, Gregor; Endlich, Nicole; Schordan, Eric; Schordan, Sandra; Chilukoti, Ravi K; Homuth, Georg; Moeller, Marcus J; Fuellen, Georg; Endlich, Karlhans
2013-07-01
Interactions between proteins crucially determine cellular structure and function. Differential analysis of the interactome may help elucidate molecular mechanisms during disease development; however, this analysis necessitates mapping of expression data on protein-protein interaction networks. These networks do not exist for the podocyte; therefore, we built PodNet, a literature-based mouse podocyte network in Cytoscape format. Using database protein-protein interactions, we expanded PodNet to XPodNet with enhanced connectivity. In order to test the performance of XPodNet in differential interactome analysis, we examined podocyte developmental differentiation and the effect of cell culture. Transcriptomes of podocytes in 10 different states were mapped on XPodNet and analyzed with the Cytoscape plugin ExprEssence, based on the law of mass action. Interactions between slit diaphragm proteins are most significantly upregulated during podocyte development and most significantly downregulated in culture. On the other hand, our analysis revealed that interactions lost during podocyte differentiation are not regained in culture, suggesting a loss rather than a reversal of differentiation for podocytes in culture. Thus, we have developed PodNet as a valuable tool for differential interactome analysis in podocytes, and we have identified established and unexplored regulated interactions in developing and cultured podocytes.
NASA Astrophysics Data System (ADS)
Mandache, C.; Khan, M.; Fahr, A.; Yanishevsky, M.
2011-03-01
Probability of detection (PoD) studies are broadly used to determine the reliability of specific nondestructive inspection procedures, as well as to provide data for damage tolerance life estimations and calculation of inspection intervals for critical components. They require inspections on a large set of samples, a fact that makes these statistical assessments time- and cost-consuming. Physics-based numerical simulations of nondestructive testing inspections could be used as a cost-effective alternative to empirical investigations. They realistically predict the inspection outputs as functions of the input characteristics related to the test piece, transducer and instrument settings, which are subsequently used to partially substitute and/or complement inspection data in PoD analysis. This work focuses on the numerical modelling aspects of eddy current testing for the bolt hole inspections of wing box structures typical of the Lockheed Martin C-130 Hercules and P-3 Orion aircraft, found in the air force inventory of many countries. Boundary element-based numerical modelling software was employed to predict the eddy current signal responses when varying inspection parameters related to probe characteristics, crack geometry and test piece properties. Two demonstrator exercises were used for eddy current signal prediction when lowering the driver probe frequency and changing the material's electrical conductivity, followed by subsequent discussions and examination of the implications on using simulated data in the PoD analysis. Despite some simplifying assumptions, the modelled eddy current signals were found to provide similar results to the actual inspections. It is concluded that physics-based numerical simulations have the potential to partially substitute or complement inspection data required for PoD studies, reducing the cost, time, effort and resources necessary for a full empirical PoD assessment.
Incidence of Trismus in Transalveolar Extraction of Lower Third Molar.
Balakrishnan, Gowri; Narendar, Ramesh; Kavin, Thangavelu; Venkataraman, Sivasubramanian; Gokulanathan, Subramaniam
2017-11-01
Conventional mandibular third molar removal produces tissue trauma that induces an inflammatory reaction, leading to postoperative sequelae, the most common ones being trismus which influences the patient's quality of life in the postoperative period. Identifying the factors determining trismus after mandibular third molar extraction helps us to evaluate and correlate the incidence of trismus with morphological and surgical factors that are associated with its incidence in the postoperative period. Patients referred to our institution for surgical removal of their impacted lower third molar between November 2014 and February 2015 were the participants of the study. Type of impaction, indication, and level of difficulty based on Pedersen criteria were obtained. Postoperative pain, swelling, and mouth opening (MO) limitations were evaluated at postoperative day (POD) 0, POD1, POD3, POD5, and POD7 and were analyzed. P < 0.05 was considered statistically significant. In this study, out of fifty patients, only nine patients had experienced limited MO during postoperative period when the duration of procedure exceeded 30 min. However, it occurred as cumulative of pericoronitis and tooth sectioning done. The postoperative trismus was more significant in disto-angular impaction ( P < 0.05) due to postoperative sequelae, swelling and pain.
Kukavica, Biljana M; Veljovicc-Jovanovicc, Sonja D; Menckhoff, Ljiljana; Lüthje, Sabine
2012-07-01
Cell wall isolated from pea roots was used to separate and characterize two fractions possessing class III peroxidase activity: (i) ionically bound proteins and (ii) covalently bound proteins. Modified SDS-PAGE separated peroxidase isoforms by their apparent molecular weights: four bands of 56, 46, 44, and 41kDa were found in the ionically bound fraction (iPOD) and one band (70kDa) was resolved after treatment of the cell wall with cellulase and pectinase (cPOD). Isoelectric focusing (IEF) patterns for iPODs and cPODs were significantly different: five iPODs with highly cationic pI (9.5-9.2) were detected, whereas the nine cPODs were anionic with pI values between pH 3.7 and 5. iPODs and cPODs showed rather specific substrate affinity and different sensitivity to inhibitors, heat, and deglycosylation treatments. Peroxidase and oxidase activities and their IEF patterns for both fractions were determined in different zones along the root and in roots of different ages. New iPODs with pI 9.34 and 9.5 were induced with root growth, while the activity of cPODs was more related to the formation of the cell wall in non-elongating tissue. Treatment with auxin that inhibits root growth led to suppression of iPOD and induction of cPOD. A similar effect was obtained with the widely used elicitor, chitosan, which also induced cPODs with pI 5.3 and 5.7, which may be specifically related to pathogen defence. The differences reported here between biochemical properties of cPOD and iPOD and their differential induction during development and under specific treatments implicate that they are involved in specific and different physiological processes.
Protective effects and mechanisms of curcumin on podophyllotoxin toxicity in vitro and in vivo
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Juan; Dai, Cai-Xia; Sun, Hua
2012-12-01
Podophyllotoxin (POD) is a naturally occurring lignan with pronounced antineoplastic and antiviral properties. POD binds to tubulin and prevents the formation of mitotic spindle. Although cases of overdose or accidental ingestion are quite often, no specific therapy is currently available to treat the POD intoxication. In the current investigation, the protective effects and mechanisms of curcumin (CUR) on podophyllotoxin toxicity were evaluated in vitro and in vivo. The results showed that CUR could protect POD-induced cytotoxicity by recovering the G2/M arrest and decrease the changes of membrane potential and microtubule structure in Vero cells. A significant decrease of mortality ratesmore » was observed in Swiss mice treated by intragastrical administration of POD + CUR as compared with POD alone. The POD + CUR group also exhibited decreases in plasma transaminases, alkaline phosphatase, lactate dehydrogenase, plasma urea, creatinine and malondialdehyde level but elevated superoxide dismutase and glutathione levels as compared to the POD group. Histological examination of the liver and kidney demonstrated less morphological changes in the treatment of POD + CUR as compared with POD alone. The mechanism of the protective effects might be due to the competitive binding of CUR with POD in the same colchicines binding site as revealed by the tubulin polymerization assay and the molecular docking analysis, and the antioxidant activity against the oxidative stress induced by POD. In summary, both in vitro and in vivo data indicated the promising role of CUR as a protective agent against the POD poisoning. Highlights: ► A potential antidote to treat the podophyllotoxin (POD) intoxication is found. ► Curcumin showed promising effects against POD poisoning in vitro and in vivo. ► The mechanisms lie in the antioxidant activity and competitive binding with tubulin.« less
Airborne Reconnoissance Pod Flijht Test
NASA Astrophysics Data System (ADS)
Henkel, P.; Sturz, R.
1987-02-01
Today's political environment has seen an increasing effort for deficit reduction resulting in defense budget cuts and decreased spending. Military capability is difficult to maintain under these circumstances unless innovation offers a low-cost alternative. One critical military capability is the ability to collect intelligence data efficiently. Tactical aerial reconnaissance its a large part of this capability. The aerial reconnaissance process usually involves dedicated aircraft with a single mission. The aircraft used for this mission are specially outfitted versions of fighter aircraft with avionics modified for the reconnaissance task. The luxury of such aircraft appears to be a thing of the past. This can be seen by recent attempts to designate a next-generation reconnaissance aircraft without success. Stopgap measures have been offered which consist of updating existing reconnaissance aircraft with new sensors and improved avionics. Upgrades definitely have their place, but do not take advantage of the multirole capabilities of modern tactical aircraft. Tactical aircraft avionics suites afford options not found in older aircraft, plus improved maintenance aspects of such systems. One method of overcoming aircraft generation gaps is to include a reconnaissance option in the form of a pod. The reconnaissance pod is not a new concept, but one which may have "found its time." The reconnaissance pod outfitted with modern sensors offers versatility, survivability and economy while reducing logistics, maintenance and training. This paper discusses a pod and sensor suite flight test program performed to verify the design features of the aerial reconnaissance pod.
Ozone risk assessment in three oak species as affected by soil water availability.
Hoshika, Yasutomo; Moura, Barbara; Paoletti, Elena
2018-03-01
To derive ozone (O 3 ) dose-response relationships for three European oak species (Quercus ilex, Quercus pubescens, and Quercus robur) under a range of soil water availability, an experiment was carried out with 2-year-old potted seedlings exposed to three levels of water availability in the soil and three levels of O 3 pollution for one growing season in an ozone free-air controlled exposure (FACE) facility. Total biomass losses were estimated relative to a hypothetical clean air at the pre-industrial age, i.e., at 10 ppb as daily average (M24). A stomatal conductance model was parameterized with inputs from the three species for calculating the stomatal O 3 flux. Exposure-based (M24, W126, and AOT40) and flux-based (phytotoxic O 3 dose (POD) 0-3 ) dose-response relationships were estimated and critical levels (CL) were calculated for a 5% decline of total biomass. Results show that water availability can significantly affect O 3 risk assessment. In fact, dose-response relationships calculated per individual species at each water availability level resulted in very different CLs and best metrics. In a simplified approach where species were aggregated on the basis of their O 3 sensitivity, the best metric was POD 0.5 , with a CL of 6.8 mmol m -2 for the less O 3 -sensitive species Q. ilex and Q. pubescens and of 3.5 mmol m -2 for the more O 3 -sensitive species Q. robur. The performance of POD 0 , however, was very similar to that of POD 0.5 , and thus a CL of 6.9 mmol m -2 POD 0 and 3.6 mmol m -2 POD 0 for the less and more O 3 -sensitive oak species may be also recommended. These CLs can be applied to oak ecosystems at variable water availability in the soil. We conclude that POD y is able to reconcile the effects of O 3 and soil water availability on species-specific oak productivity.
Chen, Xiaoping; Zhu, Wei; Azam, Sarwar; Li, Heying; Zhu, Fanghe; Li, Haifen; Hong, Yanbin; Liu, Haiyan; Zhang, Erhua; Wu, Hong; Yu, Shanlin; Zhou, Guiyuan; Li, Shaoxiong; Zhong, Ni; Wen, Shijie; Li, Xingyu; Knapp, Steve J; Ozias-Akins, Peggy; Varshney, Rajeev K; Liang, Xuanqiang
2013-01-01
The failure of peg penetration into the soil leads to seed abortion in peanut. Knowledge of genes involved in these processes is comparatively deficient. Here, we used RNA-seq to gain insights into transcriptomes of aerial and subterranean pods. More than 2 million transcript reads with an average length of 396 bp were generated from one aerial (AP) and two subterranean (SP1 and SP2) pod libraries using pyrosequencing technology. After assembly, sets of 49 632, 49 952 and 50 494 from a total of 74 974 transcript assembly contigs (TACs) were identified in AP, SP1 and SP2, respectively. A clear linear relationship in the gene expression level was observed between these data sets. In brief, 2194 differentially expressed TACs with a 99.0% true-positive rate were identified, among which 859 and 1068 TACs were up-regulated in aerial and subterranean pods, respectively. Functional analysis showed that putative function based on similarity with proteins catalogued in UniProt and gene ontology term classification could be determined for 59 342 (79.2%) and 42 955 (57.3%) TACs, respectively. A total of 2968 TACs were mapped to 174 KEGG pathways, of which 168 were shared by aerial and subterranean transcriptomes. TACs involved in photosynthesis were significantly up-regulated and enriched in the aerial pod. In addition, two senescence-associated genes were identified as significantly up-regulated in the aerial pod, which potentially contribute to embryo abortion in aerial pods, and in turn, to cessation of swelling. The data set generated in this study provides evidence for some functional genes as robust candidates underlying aerial and subterranean pod development and contributes to an elucidation of the evolutionary implications resulting from fruit development under light and dark conditions. © 2012 The Authors Plant Biotechnology Journal © 2012 Society for Experimental Biology, Association of Applied Biologists and Blackwell Publishing Ltd.
Sakai, Tatsuya; Izumi, Masahiro; Kumagai, Kenji; Kidera, Kenichi; Yamaguchi, Takayuki; Asahara, Tomohiko; Kozuru, Hideko; Jiuchi, Yuka; Mawatari, Masaaki; Osaki, Makoto; Motokawa, Satoru; Migita, Kiyoshi
2016-01-01
We conducted a randomized clinical trial to compare the effectiveness of the A-V Impulse System foot pump for reducing the incidence of deep-vein thrombosis (DVT) after total knee arthroplasty (TKA) in patients under edoxaban thromboprophylaxis. Patients undergoing primary TKA at our institution between September 2013 and March 2015 were enrolled after obtaining informed consent. The patients were randomized to use the foot pump (n = 58) and not to use the foot pump (n = 62). Both groups were given prophylactic edoxaban. Primary outcomes were any DVT as detected by bilateral ultrasonography up to postoperative day 10 (POD10) and pulmonary embolism (PE) up to POD28. The safety outcomes were bleeding and death of any cause up to POD28. Plasma D-dimer levels were measured before TKA and on POD10 after TKA. Immunoglobulin G (IgG)-class anti-PF4/heparin antibodies were measured using an IgG-specific enzyme-linked immunosorbent assay. The incidences of any DVT up to POD28 were 31.0% and 17.7% in patients with or without the foot pump, respectively. The incidences of major bleeding up to POD28 were 5.1% and 4.8% in patients with or without the foot pump, respectively. Foot pump use did not significantly reduce the incidence of DVTs in patients undergoing TKA under edoxaban thromboprophylaxis. Although seroconversion of anti-PF4/heparin antibodies was confirmed in one-fourth of patients, the seroconversion rates did not differ between patients with (20.7%) or without (25.8%) foot pump use. This study shows that the A-V Impulse system foot pump did not affect the incidence of DVT under edoxaban thromboprophylaxis in patients undergoing TKA. Seroconversion of anti-PF4/heparin antibodies was detected in a significant number of patients who underwent TKA under antithrombotic prophylaxis using edoxaban.
NASA Astrophysics Data System (ADS)
Brux, O.; van der Walle, P.; van der Donck, J. C. J.; Dress, P.
2011-11-01
Extreme Ultraviolet Lithography (EUVL) is the most promising solution for technology nodes 16nm (hp) and below. However, several unique EUV mask challenges must be resolved for a successful launch of the technology into the market. Uncontrolled introduction of particles and/or contamination into the EUV scanner significantly increases the risk for device yield loss and potentially scanner down-time. With the absence of a pellicle to protect the surface of the EUV mask, a zero particle adder regime between final clean and the point-of-exposure is critical for the active areas of the mask. A Dual Pod concept for handling EUV masks had been proposed by the industry as means to minimize the risk of mask contamination during transport and storage. SuSS-HamaTech introduces MaskTrackPro InSync as a fully automated solution for the handling of EUV masks in and out of this Dual Pod System and therefore constitutes an interface between various tools inside the Fab. The intrinsic cleanliness of each individual handling and storage step of the inner shell (EIP) of this Dual Pod and the EUV mask inside the InSync Tool has been investigated to confirm the capability for minimizing the risk of cross-contamination. An Entegris Dual Pod EUV-1000A-A110 has been used for the qualification. The particle detection for the qualification procedure was executed with the TNO's RapidNano Particle Scanner, qualified for particle sizes down to 50nm (PSL equivalent). It has been shown that the target specification of < 2 particles @ 60nm per 25 cycles has been achieved. In case where added particles were measured, the EIP has been identified as a potential root cause for Ni particle generation. Any direct Ni-Al contact has to be avoided to mitigate the risk of material abrasion.
Ren, Huajian; Wang, Gefei; Gu, Guosheng; Hu, Qiongyuan; Li, Guanwei; Hong, Zhiwu; Wu, Xiuwen; Ren, Jianan
2017-05-25
To investigate the predictive value of procalcitonin(PCT) in postoperative intra-abdominal infections (IAI) after definitive operation of intestinal fistulae(IF). With the exclusion of emergence operation, preoperative clinical infection, preoperative renal or hepatic dysfunction, and age less than 18 years, a total of 356 consecutive patients who underwent elective digestive tract reconstruction of intestinal fistulae from February 2012 to December 2015 at Intestinal Fistula Center of Jinling Hospital were prospectively enrolled in the study. All the patients were divided into IAI group (26 cases, 21 of anastomosis leakage and 5 of peritoneal abscess) and non-IAI group (330 cases) based on the existence of postoperative IAI. The non-IAI group was then divided into two subgroups of other infection (93 cases) and non-infection(237 cases) according to the presence of other infections. Plasma PCT level, serum CRP concentration and WBC count were assessed preoperatively and on postoperative days (PODs) 1, 3, 5, 7 by immunofluorescence, turbidimetry and automatic blood analyzer, respectively. The predictive value of each marker for IAI was calculated by receiver operating characteristic (ROC) curve. There was no significant difference in general clinical data between IAI and non-IAI group (all P>0.05). The proportions of multi-IF (53.8%, 14/26) and colectomy (61.5%, 16/26) in IAI group were higher than those of non-IAI group [20.0% (66/330), χ 2 =15.847, P=0.000 and 31.2%(103/330), χ 2 =9.961, P=0.002]. Differences of preoperative PCT, CRP and WBC levels among IAI, other infection and non-infection groups were not significant. These three markers all increased obviously and immediately after surgery. PCT and WBC values reached the peak point on POD 1, whereas CRP on POD 3. In IAI group, mean PCT values were (5.4±4.2) μg/L, (2.9±1.9) μg/L and (1.6±1.8) μg/L on POD 1, POD 3 and POD 5, respectively, which were higher than those of other infection group [(4.2±8.7) μg/L, (1.9±3.8) μg/L and (0.6±0.8) μg/L] and non-infection group [(2.7±5.8) μg/L, (1.1±1.7) μg/L and (0.5±0.7) μg/L, all P<0.05]. Mean CRP values in IAI group were 99.4 mg/L and 183.9 mg/L respectively on POD 1 and POD 3,and mean WBC values of IAI group on POD 1, POD 3 and POD 5 were 16.0×10 9 /L, 10.8×10 9 /L and 8.7×10 9 /L, respectively, which were all significantly higher than those in the other 2 groups (all P<0.05). No significant differences were obtained between other infection group and non-infection group in all these three markers (all P>0.05). ROC curve demonstrated that PCT had the biggest area under the curve (AUC) of 0.86 and 0.84 on POD 3 and POD 5, with the cut-off value of 0.98 μg/L and 0.83 μg/L, 92.0% sensitivity and 74.0% specificity, 91.0% sensitivity and 73.0% specificity, respectively. The highest AUC was 0.72 on POD 3 for CRP and 0.71 on POD 3 for WBC, with 80.0% sensitivity and 54.0% specificity, 56.0% sensitivity and 73.0% specificity, respectively. The value of procalcitonin above 0.98 μg/L on POD 3 and 0.83 μg/L on POD 5 can predict the occurrence of IAI after definitive operations of intestinal fistulae.
2011-02-06
VANDENBERG AIR FORCE BASE, Calif. -- At Space Launch Complex 576-E at Vandenberg Air Force Base in California, the Poly Picosatellite Orbital Deployer, or P-POD, assembly is imaged wrapped in its thermal insulation blanket and sheeting and the attached Anodized gold aluminum bracket interface. The bracket is the connection point between the P-POD and the aft end of the Taurus rocket's third stage. The P-POD holds three CubeSats or tiny satellites, designed and created by university and college students that will be carried on the Taurus rocket along with the Glory spacecraft. The Orbital Sciences Corp. Taurus XL rocket will carry Glory into low Earth orbit. Once Glory reaches orbit, it will collect data on the properties of aerosols and black carbon. It also will help scientists understand how the sun's irradiance affects Earth's climate. Launch is scheduled for 5:09 a.m. EST Feb. 23. For information, visit www.nasa.gov/glory. Photo credit: NASA/Randy Beaudoin, VAFB
Free Space Optical Communication in the Military Environment
2014-09-01
Communications Commission FDA Food and Drug Administration FMV Full Motion Video FOB Forward Operating Base FOENEX Free-Space Optical Experimental Network...from radio and voice to chat message and email. Data-rich multimedia content, such as high-definition pictures, video chat, video files, and...introduction of full-motion video (FMV) via numerous different Intelligence Surveillance and Reconnaissance (ISR) systems, such as targeting pods on
NASA Technical Reports Server (NTRS)
Collette, J. G. R.
1984-01-01
A test was conducted in the NASA/Ames Research Center 9x7-foot Supersonic Wind Tunnel to help resolve an anomaly that developed during the STS-6 orbiter flight wherein sections of the Advanced Flexible Reusable Surface Insulation (AFRSI) covering the OMS pods suffered some damage. A one-third scale two-dimensional shell structure model of an OMS pod cross-section was employed to support the test articles. These consisted of 15 AFRSI blanket panels form-fitted over the shell structures for exposure to simulated flight conditions. Of six baseline blankets, two were treated with special surface coatings. Two other panels were configured with AFRSI sections removed from the OV099 orbiter vehicle after the STS-6 flight. Seven additional specimens incorporated alternative designs and repairs. Following a series of surface pressure calibration runs, the specimens were exposed to simulated ascent and entry dynamic pressure profiles. Entry conditions included the use of a vortex generator to evaluate the effect of shed vortices on the AFRSI located in the area of concern.
NASA Astrophysics Data System (ADS)
Ren, Xia; Yang, Yuanxi; Zhu, Jun; Xu, Tianhe
2017-11-01
Intersatellite Link (ISL) technology helps to realize the auto update of broadcast ephemeris and clock error parameters for Global Navigation Satellite System (GNSS). ISL constitutes an important approach with which to both improve the observation geometry and extend the tracking coverage of China's Beidou Navigation Satellite System (BDS). However, ISL-only orbit determination might lead to the constellation drift, rotation, and even lead to the divergence in orbit determination. Fortunately, predicted orbits with good precision can be used as a priori information with which to constrain the estimated satellite orbit parameters. Therefore, the precision of satellite autonomous orbit determination can be improved by consideration of a priori orbit information, and vice versa. However, the errors of rotation and translation in a priori orbit will remain in the ultimate result. This paper proposes a constrained precise orbit determination (POD) method for a sub-constellation of the new Beidou satellite constellation with only a few ISLs. The observation model of dual one-way measurements eliminating satellite clock errors is presented, and the orbit determination precision is analyzed with different data processing backgrounds. The conclusions are as follows. (1) With ISLs, the estimated parameters are strongly correlated, especially the positions and velocities of satellites. (2) The performance of determined BDS orbits will be improved by the constraints with more precise priori orbits. The POD precision is better than 45 m with a priori orbit constrain of 100 m precision (e.g., predicted orbits by telemetry tracking and control system), and is better than 6 m with precise priori orbit constraints of 10 m precision (e.g., predicted orbits by international GNSS monitoring & Assessment System (iGMAS)). (3) The POD precision is improved by additional ISLs. Constrained by a priori iGMAS orbits, the POD precision with two, three, and four ISLs is better than 6, 3, and 2 m, respectively. (4) The in-plane link and out-of-plane link have different contributions to observation configuration and system observability. The POD with weak observation configuration (e.g., one in-plane link and one out-of-plane link) should be tightly constrained with a priori orbits.
NASA Technical Reports Server (NTRS)
Delin, Kevin A. (Inventor); Jackson, Shannon P. (Inventor)
2011-01-01
A Sensor Web formed of a number of different sensor pods. Each of the sensor pods include a clock which is synchronized with a master clock so that all of the sensor pods in the Web have a synchronized clock. The synchronization is carried out by first using a coarse synchronization which takes less power, and subsequently carrying out a fine synchronization to make a fine sync of all the pods on the Web. After the synchronization, the pods ping their neighbors to determine which pods are listening and responded, and then only listen during time slots corresponding to those pods which respond.
Hemodynamics of a Patient-Specific Aneurysm Model with Proper Orthogonal Decomposition
NASA Astrophysics Data System (ADS)
Han, Suyue; Chang, Gary Han; Modarres-Sadeghi, Yahya
2017-11-01
Wall shear stress (WSS) and oscillatory shear index (OSI) are two of the most-widely studied hemodynamic quantities in cardiovascular systems that have been shown to have the ability to elicit biological responses of the arterial wall, which could be used to predict the aneurysm development and rupture. In this study, a reduced-order model (ROM) of the hemodynamics of a patient-specific cerebral aneurysm is studied. The snapshot Proper Orthogonal Decomposition (POD) is utilized to construct the reduced-order bases of the flow using a CFD training set with known inflow parameters. It was shown that the area of low WSS and high OSI is correlated to higher POD modes. The resulting ROM can reproduce both WSS and OSI computationally for future parametric studies with significantly less computational cost. Agreement was observed between the WSS and OSI values obtained using direct CFD results and ROM results.
Optical datacenter network employing slotted (TDMA) operation for dynamic resource allocation
NASA Astrophysics Data System (ADS)
Bakopoulos, P.; Tokas, K.; Spatharakis, C.; Patronas, I.; Landi, G.; Christodoulopoulos, K.; Capitani, M.; Kyriakos, A.; Aziz, M.; Reisis, D.; Varvarigos, E.; Zahavi, E.; Avramopoulos, H.
2018-02-01
The soaring traffic demands in datacenter networks (DCNs) are outpacing progresses in CMOS technology, challenging the bandwidth and energy scalability of currently established technologies. Optical switching is gaining traction as a promising path for sustaining the explosive growth of DCNs; however, its practical deployment necessitates extensive modifications to the network architecture and operation, tailored to the technological particularities of optical switches (i.e. no buffering, limitations in radix size and speed). European project NEPHELE is developing an optical network infrastructure that leverages optical switching within a software-defined networking (SDN) framework to overcome the bandwidth and energy scaling challenges of datacenter networks. An experimental validation of the NEPHELE data plane is reported based on commercial off-the-shelf optical components controlled by FPGA boards. To facilitate dynamic allocation of the network resources and perform collision-free routing in a lossless network environment, slotted operation is employed (i.e. using time-division multiple-access - TDMA). Error-free operation of the NEPHELE data plane is verified for 200 μs slots in various scenarios that involve communication between Ethernet hosts connected to custom-designed top-of-rack (ToR) switches, located in the same or in different datacenter pods. Control of the slotted data plane is obtained through an SDN framework comprising an OpenDaylight controller with appropriate add-ons. Communication between servers in the optical-ToR is demonstrated with various routing scenarios, concerning communication between hosts located in the same rack or in different racks, within the same or different datacenter pods. Error-free operation is confirmed for all evaluated scenarios, underpinning the feasibility of the NEPHELE architecture.
Detail view of the aft section, port side, of the ...
Detail view of the aft section, port side, of the Orbiter Discovery from an elevated platform in the Vehicle Assembly Building at NASA's Kennedy Space Center. Note the removed Orbiter Maneuvering System/Reaction Control System pod from the base of the vertical stabilizer the strongback ground-support equipment attached to the payload bay door. This view is also a good view of the leading edge and top surface of the Orbiter wing. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX
Xenon plasma sustained by pulse-periodic laser radiation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rudoy, I. G.; Solovyov, N. G.; Soroka, A. M.
2015-10-15
The possibility of sustaining a quasi-stationary pulse-periodic optical discharge (POD) in xenon at a pressure of p = 10–20 bar in a focused 1.07-μm Yb{sup 3+} laser beam with a pulse repetition rate of f{sub rep} ⩾ 2 kHz, pulse duration of τ ⩾ 200 μs, and power of P = 200–300 W has been demonstrated. In the plasma development phase, the POD pulse brightness is generally several times higher than the stationary brightness of a continuous optical discharge at the same laser power, which indicates a higher plasma temperature in the POD regime. Upon termination of the laser pulse,more » plasma recombines and is then reinitiated in the next pulse. The initial absorption of laser radiation in successive POD pulses is provided by 5p{sup 5}6s excited states of xenon atoms. This kind of discharge can be applied in plasma-based high-brightness broadband light sources.« less
Technical concept of the UK Tornado stand-off reconnaissance system
NASA Astrophysics Data System (ADS)
Dyer, Gavin R.
1996-11-01
The operational limitations exposed during the Gulf War have led to the formulation of a requirement for anew generation of tactical reconnaissance pod for the Royal Air Force Tornado aircraft. The pod will contain a high resolution Electro-Optical sensor capable of day and night-time operations, digital recording of the imagery for airborne replay and ground exploitation, and a data-link for real time/near real time imagery transmission. The program requirement includes a deployable ground exploitation system to provide a comprehensive independent capability. The interoperability of the air and ground segments with other systems is addressed through NATO standardization agreements. This system will provide the Tornado with a highly flexible stand-off imaging system for day/night operations from a range of altitudes.
NASA Astrophysics Data System (ADS)
Muslimin; Wijayanti, W.; Anshary, A.; Basri, Z.; Cruz, A. F.; Suwastika, I. N.; Shiina, T.
2018-04-01
Cacao (Theobroma cacao L.) is one major agricultural commodity from central Sulawesi, which is significantly affected by a range of pest and diseases including Cacao Pod Borer (CPB), Pod Rod Diseases (PRD), and Vascular Streak Dieback (VSD). Intensive and extensive approaches, including introduction of various new superior cultivars/clones, and development of eco-friendly agricultural system were implemented in order to overtake that problem. Here, we observed the performance of three different clones (namely: Sulawesi 1, MCC01, and Tadulako-1) in two different locations (Parigi and Poso-which located along east coast of central Sulawesi province), and under two different Agricultural management system (echo-friendly-intensive and Non-Intensive). All clones tested showed their well-adapted and suitable to local conditions. The performance of each clone can be improved by intensive management system. Based on all observed parameters (number of wet bean per pot, bean count, fat and shell percentage, and percentage of infection) it convincingly showed that intensive management system was working well in improving the quality and quantity of cacao beans production, and it fit to commercial requirements. The highest rate of infection was by Phytophthora, and no significant differences on the overall performances. Clones of Sulawesi-1 and MCC01 most likely was better than Tadulako-1.
TerraSAR-X precise orbit determination with real-time GPS ephemerides
NASA Astrophysics Data System (ADS)
Wermuth, Martin; Hauschild, Andre; Montenbruck, Oliver; Kahle, Ralph
TerraSAR-X is a German Synthetic Aperture Radar (SAR) satellite, which was launched in June 2007 from Baikonour. Its task is to acquire radar images of the Earth's surface. In order to locate the radar data takes precisely, the satellite is equipped with a high-quality dual-frequency GPS receiver -the Integrated Geodetic and Occultation Receiver (IGOR) provided by the GeoForschungsZentrum Potsdam (GFZ). Using GPS observations from the IGOR instrument in a reduced dynamic precise orbit determination (POD), the German Space Operations Center (DLR/GSOC) is computing rapid and science orbit products on a routine basis. The rapid orbit products arrive with a latency of about one hour after data reception with an accuracy of 10-20 cm. Science orbit products are computed with a latency of five days achieving an accuracy of about 5cm (3D-RMS). For active and future Earth observation missions, the availability of near real-time precise orbit information is becoming more and more important. Other applications of near real-time orbit products include the processing of GNSS radio occulation measurements for atmospheric sounding as well as altimeter measurements of ocean surface heights, which are nowadays employed in global weather and ocean circulation models with short latencies. For example after natural disasters it is necessary to evaluate the damage by satellite images as soon as possible. The latency and quality of POD results is mainly driven by the availability of precise GPS ephemerides. In order to have high-quality GPS ephemerides available at real-time, GSOC has developed the real-time clock estimation system RETICLE. The system receives NTRIP-data streams with GNSS observations from the global tracking network of IGS in real-time. Using the known station position, RETICLE estimates precise GPS satellite clock offsets and drifts based on the most recent available IGU predicted orbits. The clock offset estimates have an accuracy of better than 0.3 ns and are globally valid. The latency of the estimated clocks is approximately 7 seconds. Another limiting factor is the frequency of satellite downlinks and the latency of the data transfer from the ground station to the computation center. Therefore a near real-time scenario is examined in which the satellite has about one ground station contact per orbit or respectively one contact in 90 minutes. The results of the near real-time POD are evaluated in an internal consistency check and compared against the science orbit solution and laser ranging observations.
Selection of Soybean Pods by the Stink Bugs, Nezara viridula and Piezodorus guildinii
Molina, Gonzalo A. R.; Trumper, Eduardo V.
2012-01-01
Different biological parameters of the stink bugs, Nezara viridula L. and Piezodorus guildinii Westwood (Hemiptera: Pentatomidae), are affected by the developmental stage of the soybean (Glycine max Merrill) pods they feed on. These effects of the soybean on the stink bugs could represent a selection pressure leading to the ability of these species to discriminate the phenological stage of soybean pods, and, therefore, to exhibit feeding preferences. We designed three studies: (1) Distant detection of soybean pods through an olfactometer; (2) Free choice tests to evaluate preferences for soybean pods of different developmental stages; (3) No choice tests to study effects of soybean pod development on feeding time and number of probes. Stink bugs showed no differential response to olfactometer arms with or without soybean pods, suggesting an inability to detect soybean volatiles. Free choice tests showed no species effects on pods selection, but significant differences among fifth instar nymphs, adult male, and adult females. Fifth instar nymphs fed more frequently on soybean pods of advanced development stages compared to female adults, despite previous evidence showing poor development of stink bugs fed pods of the same stage. No choice tests showed significant effects of stink bug species, stink bug stage and sex, and soybean pod phenology. N. viridula expressed shorter feeding times and higher numbers of probes than P. guildinii. The highest numbers of probes of both species were observed when they were fed soybean pods in early phenological stages. When placed in direct contact with food, fifth instar nymphs prefered to feed on more developed pods, despite these pods being suboptimal food items. These results suggest that for the ecological time framework of soybean-stink bugs coexistence, around thirty-five years in Argentina, the selection pressure was not enough for stink bugs to evolve food preferences that match their performance on soybean pods of different development stages. PMID:23437991
Yip, Kenneth W.; Cuddy, Michael; Pinilla, Clemencia; Giulanotti, Marc; Heynen-Genel, Susanne; Matsuzawa, Shu-ichi; Reed, John C.
2014-01-01
PML is a tumor suppressor that promotes apoptosis through both p53-dependent and - independent mechanisms, participates in Rb-mediated cell cycle arrest, inhibits neoangiogenesis, and contributes to maintenance of genomic stability. PML also plays a role in host defense against viruses, conferring antiviral activity. When active, PML localizes to subnuclear structures named PML oncogenic domains (PODs) or PML nuclear bodies (PML-NBs), whereas inactive PML is located diffusely throughout the nucleus of cells, thus providing a morphological indicator. Known activators of PML include arsenicals and interferons, however, these agents induce a plethora of toxic effects, limiting their effectiveness. The objective of the current study was to develop a high content screening (HCS) assay for the identification of chemical activators of PML. We describe methods for automated analysis of POD formation using high throughput microscopy (HTM) to localize PML immunofluorescence in conjunction with image analysis software for POD quantification. Using this HCS assay in 384 well format, we performed pilot screens of a small synthetic chemical library and mixture-based combinatorial libraries, demonstrating the robust performance of the assay. HCS counter-screening assays were also developed for hit characterization, based on immunofluorescence analyses of the subcellular location of phosphorylated H2AX or phosphorylated CHK1, which increase in a punctate nuclear pattern in response to DNA damage. Thus, the HCS assay devised here represents a high throughput screen that can be utilized to discover POD-inducing compounds that may restore the tumor suppressor activity of PML in cancers or possibly promote anti-viral states. PMID:21233309
Thomas, Russell S.
2013-01-01
Based on existing data and previous work, a series of studies is proposed as a basis toward a pragmatic early step in transforming toxicity testing. These studies were assembled into a data-driven framework that invokes successive tiers of testing with margin of exposure (MOE) as the primary metric. The first tier of the framework integrates data from high-throughput in vitro assays, in vitro-to-in vivo extrapolation (IVIVE) pharmacokinetic modeling, and exposure modeling. The in vitro assays are used to separate chemicals based on their relative selectivity in interacting with biological targets and identify the concentration at which these interactions occur. The IVIVE modeling converts in vitro concentrations into external dose for calculation of the point of departure (POD) and comparisons to human exposure estimates to yield a MOE. The second tier involves short-term in vivo studies, expanded pharmacokinetic evaluations, and refined human exposure estimates. The results from the second tier studies provide more accurate estimates of the POD and the MOE. The third tier contains the traditional animal studies currently used to assess chemical safety. In each tier, the POD for selective chemicals is based primarily on endpoints associated with a proposed mode of action, whereas the POD for nonselective chemicals is based on potential biological perturbation. Based on the MOE, a significant percentage of chemicals evaluated in the first 2 tiers could be eliminated from further testing. The framework provides a risk-based and animal-sparing approach to evaluate chemical safety, drawing broadly from previous experience but incorporating technological advances to increase efficiency. PMID:23958734
NASA Technical Reports Server (NTRS)
Lindqwister, Ulf J.; Lichten, Stephen M.; Davis, Edgar S.; Theiss, Harold L.
1993-01-01
Topex/Poseidon, a cooperative satellite mission between United States and France, aims to determine global ocean circulation patterns and to study their influence on world climate through precise measurements of sea surface height above the geoid with an on-board altimeter. To achieve the mission science aims, a goal of 13-cm orbit altitude accuracy was set. Topex/Poseidon includes a Global Positioning System (GPS) precise orbit determination (POD) system that has now demonstrated altitude accuracy better than 5 cm. The GPS POD system includes an on-board GPS receiver and a 6-station GPS global tracking network. This paper reviews early GPS results and discusses multi-mission capabilities available from a future enhanced global GPS network, which would provide ground-based geodetic and atmospheric calibrations needed for NASA deep space missions while also supplying tracking data for future low Earth orbiters. Benefits of the enhanced global GPS network include lower operations costs for deep space tracking and many scientific and societal benefits from the low Earth orbiter missions, including improved understanding of ocean circulation, ocean-weather interactions, the El Nino effect, the Earth thermal balance, and weather forecasting.
NASA Technical Reports Server (NTRS)
1991-01-01
When Michael Henry wanted to start an aerial video service, he turned to Johnson Space Center for assistance. Two NASA engineers - one had designed and developed TV systems in Apollo, Skylab, Apollo- Soyuz and Space Shuttle programs - designed a wing-mounted fiberglass camera pod. Camera head and angles are adjustable, and the pod is shaped to reduce vibration. The controls are located so a solo pilot can operate the system. A microprocessor displays latitude, longitude, and bearing, and a GPS receiver provides position data for possible legal references. The service has been successfully utilized by railroads, oil companies, real estate companies, etc.
Vision systems for manned and robotic ground vehicles
NASA Astrophysics Data System (ADS)
Sanders-Reed, John N.; Koon, Phillip L.
2010-04-01
A Distributed Aperture Vision System for ground vehicles is described. An overview of the hardware including sensor pod, processor, video compression, and displays is provided. This includes a discussion of the choice between an integrated sensor pod and individually mounted sensors, open architecture design, and latency issues as well as flat panel versus head mounted displays. This technology is applied to various ground vehicle scenarios, including closed-hatch operations (operator in the vehicle), remote operator tele-operation, and supervised autonomy for multi-vehicle unmanned convoys. In addition, remote vision for automatic perimeter surveillance using autonomous vehicles and automatic detection algorithms is demonstrated.
ELaNa - Educational Launch of Nanosatellite Providing Routine RideShare Opportunities
NASA Technical Reports Server (NTRS)
Skrobot, Garrett Lee; Coelho, Roland
2012-01-01
Since the creation of the NASA CubeSat Launch Initiative (NCSLI), the need for CubeSat rideshares has dramatically increased. After only three releases of the initiative, a total of 66 CubeSats now await launch opportunities. So, how is this challenge being resolved? NASA's Launch Services Program (LSP) has studied how to integrate PPODs on Athena, Atlas V, and Delta IV launch vehicles and has been instrumental in developing several carrier systems to support CubeSats as rideshares on NASA missions. In support of the first two ELaNa missions the Poly-Picosatellite Orbital Deployer (P-POD) was adapted for use on a Taurus XL (ELaNa I) and a Delta n (ELaNa III). Four P-PODs, which contained a total eight CubeSats, were used on these first ELaNa missions. Next up is ELaNa VI, which will launch on an Atlas V in August 2012. The four ELaNa VI CubeSats, in three P-PODs, are awaiting launch, having been integrated in the NPSCuLite. To increase rideshare capabilities, the Launch Services Program (LSP) is working to integrate P-PODs on Falcon 9 missions. The proposed Falcon 9 manifest will provide greater opportunities for the CubeSat community. For years, the standard CubeSat size was 1 U to 3U. As the desire to include more science in each cube grows, so does the standard CubeSat size. No longer is a 1 U, 1.5U, 2U or 3U CubeSat the only option available; the new CubeSat standard will include 6U and possibly even 12U. With each increase in CubeSat size, the CubeSat community is pushing the capability of the current P-POD design. Not only is the carrier system affected, but integration to the Launch Vehicle is also a concern. The development of a system to accommodate not only the 3U P-POD but also carriers for larger CubeSats is ongoing. LSP considers payloads in the lkg to 180 kg range rideshare or small/secondary payloads. As new and emerging small payloads are developed, rideshare opportunities and carrier systems need to be identified and secured. The development of a rideshare carrier system is not always cost effective. Sometimes a launch vehicle with an excellent performance record appears to be a great rideshare candidate however, after completing a feasibility study, LSP may determine that the cost of the rideshare carrier system is too great and, due to budget constraints, the development cannot go forward. With the current budget environment, one cost effective way to secure rideshare opportunities is to look for synergy with other government organizations that share the same interest.
Views of EVA performed during STS-6
NASA Technical Reports Server (NTRS)
1983-01-01
Two STS-6 mission specialists busy near the aft bulkhead were photographed with a 70mm camera. Astronauts F. Story Musgrave (at winch device near center) and Donald H. Peterson are setting up winch operations at the aft bulkhead as a simulation for a contingency extravehicular activity (EVA). The orbital maneuvering system (OMS) pods are seen in the background (30211); Musgrave translates down the Challenger's payload bay door hinge line with a bag of latch tools. In the lower left foreground are three canisters containing three getaway special (GAS) experiments. Part of the starboard wing and OMS pod are seen in the background. The gold-foil protected object on the right is the airborne support equipment for the inertial upper stage (IUS) (30212); Peterson (starboard side) and Musgrave evaluate the handrail system on the starboard longeron and aft bulkhead during an EVA. Behind them the vertical stabilizer and OMS pods frame a portion of Mexico's state of Jalisco (30213); Musgrave sus
Protection efficiency of a standard compliant EUV reticle handling solution
NASA Astrophysics Data System (ADS)
He, Long; Lystad, John; Wurm, Stefan; Orvek, Kevin; Sohn, Jaewoong; Ma, Andy; Kearney, Patrick; Kolbow, Steve; Halbmaier, David
2009-03-01
For successful implementation of extreme ultraviolet lithography (EUVL) technology for late cycle insertion at 32 nm half-pitch (hp) and full introduction for 22 nm hp high volume production, the mask development infrastructure must be in place by 2010. The central element of the mask infrastructure is contamination-free reticle handling and protection. Today, the industry has already developed and balloted an EUV pod standard for shipping, transporting, transferring, and storing EUV masks. We have previously demonstrated that the EUV pod reticle handling method represents the best approach in meeting EUVL high volume production requirements, based on then state-of-the-art inspection capability at ~53nm polystyrene latex (PSL) equivalent sensitivity. In this paper, we will present our latest data to show defect-free reticle handling is achievable down to 40 nm particle sizes, using the same EUV pod carriers as in the previous study and the recently established world's most advanced defect inspection capability of ~40 nm SiO2 equivalent sensitivity. The EUV pod is a worthy solution to meet EUVL pilot line and pre-production exposure tool development requirements. We will also discuss the technical challenges facing the industry in refining the EUV pod solution to meet 22 nm hp EUVL production requirements and beyond.
Zhao, Chunxia; Gunawardana, Manjula; Villinger, Francois; Baum, Marc M; Remedios-Chan, Mariana; Moench, Thomas R; Zeitlin, Larry; Whaley, Kevin J; Bohorov, Ognian; Smith, Thomas J; Anderson, Deborah J; Moss, John A
2017-07-01
The broadly neutralizing antibody (bNAb) VRC01, capable of neutralizing 91% of known human immunodeficiency virus type 1 (HIV-1) isolates in vitro , is a promising candidate microbicide for preventing sexual HIV infection when administered topically to the vagina; however, accessibility to antibody-based prophylactic treatment by target populations in sub-Saharan Africa and other underdeveloped regions may be limited by the high cost of conventionally produced antibodies and the limited capacity to manufacture such antibodies. Intravaginal rings of the pod design (pod-IVRs) delivering Nicotiana -manufactured VRC01 (VRC01-N) over a range of release rates have been developed. The pharmacokinetics and preliminary safety of VRC01-N pod-IVRs were evaluated in a rhesus macaque model. The devices sustained VRC01-N release for up to 21 days at controlled rates, with mean steady-state VRC01-N levels in vaginal fluids in the range of 10 2 to 10 3 μg g -1 being correlated with in vitro release rates. No adverse safety indications were observed. These findings indicate that pod-IVRs are promising devices for the delivery of the candidate topical microbicide VRC01-N against HIV-1 infection and merit further preclinical evaluation. Copyright © 2017 American Society for Microbiology.
NASA Technical Reports Server (NTRS)
Zelensky, Nikita P.; Lemoine, Frank G.; Chinn, Douglas; Beckley, Brain D.; Melachroinos, Stavros; Rowlands, David D.; Luthcke, Scott B.
2011-01-01
Modeling of the Time Variable Gravity (TVG) is believed to constitute one of the the largest remaining source of orbit error for altimeter satellite POD. The GSFC operational TVG model consists of forward modeling the atmospheric gravity using ECMWF 6-hour pressure data, a GRACE derived 20x20 annual field to account for changes in the hydrology and ocean water mass, and linear rates for C20, C30, C40, based on 17 years of SLR data analysis (IERS 2003) using the EIGEN-GL04S1 (a GRACE+Lageos-based geopotential solution). Although the GSFC Operational model can be applied from 1987, there may be long-term variations not captured by these linear models, and more importantly the linear models may not be consistent with more recent surface mass trends due to global climate change, We have evaluated the impact of TVG in two different wavs: (1) by using the more recent EIGEN-6S gravity model developed by the GFZ/GRGS tearm, which consists of annual, semi-annual and secular changes in the coefficients to 50x50 determined over 8(?) years of GRACE+Lageos+GOCE data (2003-200?): (2) Application of 4x4 solutions developed from a multi satellite SLR+DORIS solution based on GGM03S that span the period from 1993 to 2011. We have evaluated the recently released EIGEN6s static and time-varying gravity field for Jason-2 (J2). Jason-I (J1), and TOPEX/Posiedon (TP) Precise Orbit Determination (POD) spanning 1993-2011. Although EIGEN6s shows significant improvement for J2POD spanning 2008 - 2011, it also shows significant degradation for TP POD from 1992. The GSFC 4x4 time SLR+DORIS-based series spans 1993 to mid 2011, and shows promise for POD. We evaluate the performance of the different TVG models based on analysis of tracking data residuals use of independent data such as altimeter crossovers, and through analysis of differences with internally-generated and externally generated orbits.
NASA Astrophysics Data System (ADS)
Rachmat, Devita; Johar Mawarani, Lizda; Dewi Risanti, Doty
2018-01-01
Cocoa pod husk (Theobroma cacao l.) is a waste from cocoa beans processing. In this research we employ cocoa pod husk as activated carbon to decrease the value of FFA (Free Fatty Acid) in waste cooking oil and as K2CO3 catalyst in biodiesel production process from waste cooking oil. Cocoa pod husk was crusched and grounded into powder that passed thorugh 60 mesh-screen. As activated carbon, cocoa pod husk was firstly carbonized at three variant temperatures i.e 250°C, 300°C and 350°C. The activation process was done using HCl 2M as activator. Based on the results of XRD and FTIR, the carbonization at all variant temperatures does not cause a significant changes in terms of crystallite structure and water content. The pore of activated carbon started to form in sample that was carbonized at 350°C resulting in pore diameter of 5.14644 nm. This result was supported by the fact that the ability of this activated carbon in reducing the FFA of waste cooking oil was the most pronounced one, i.e. up to 86.7% of FFA. It was found that the performance of cocoa pod husk’s activated carbon in reducing FFA is more effective than esterification using H2SO4 which can only decrease 80.8%. On the other hand, the utilization as K2CO3 catalyst was carried out by carbonization at temperature 650°C and extraction using aquadest solvent. The extraction of cocoa pod husk produced 7.067% K2CO3 catalyst. According to RD results the fraction of K2CO3 compound from the green catalysts is the same as the commercial (SAP, 99%) that is ≥ 60%. From the obtained results, the best yield percentage was obtained using K2CO3 catalyst from cacao pod husk extract, i.e. 73-85%. To cope with biodiesel conversion efficiency, a two-step process consisting pretreatment with activated carbon carbonized at 350°C and esterification with K2CO3 from cocoa pod husk catalyst was developed. This two-step process could reach a high conversion of 85%. From the results it was clear that the produced biodiesel fuel was within the recommended SNI 7182: 2015 standard.
Rahman, M. Mahbubur
2017-01-01
Riptortus pedestris (Fabricius) and Halyomorpha halys (Stål) cause injury to soybeans by piercing and sucking pods and seeds. Growers believe that new damage decreases near to harvest despite the occurrence of these bugs at that time. As this question has never been assessed, we evaluated two diets: a) mature soybean pods (dried shell + dried soybean seeds) and b) dried soybean seeds for the two bugs by assessing their biological, behavioral, and morphological attributes on each diet in laboratory. While nymphs of both species were able to develop and adults able to reproduce on the tested diets, bugs fed on pods had longer development times and 2.2 to 5.0 times higher mortality rates than bugs fed on seeds. Furthermore, adult longevity of R. pedestris and H. halys fed on pods was 8.4 and 7.5 days shorter, respectively, than that of bugs fed on seeds. However, pod feeding had no effect on adult fecundity or egg viability. In a behavioral choice test, adult R. pedestris preferred seeds over pods and probed seeds longer than pods. On average, adult H. halys also preferred seeds over pods, although 15.6% of H. halys showed the reverse, preferring pods over seeds. The proboscis length and estimated depth of stylet penetration into the host tissue of both nymphs and adults of both species was much greater than the thickness of the pod shell, suggesting that mouthpart structure does not explain the negative effects of pods vs. seeds. In conclusion, mature soybean pods were found to be a suitable food source for both R. pedestris and H. halys despite some negative effects, and thus careful attention should be paid to the population levels of these two bugs approaching harvest to reduce economic damage in soybean. PMID:28430798
Das, Rasel; Hamid, Sharifah Bee Abd; Annuar, Mohamad Suffian Mohamad
2016-10-10
The present study reported for the first time covalent immobilization of protocatechuate 3,4-dioxygenase (3,4-POD) onto functionalized multi-walled carbon nanotubes (F-MWCNT) for degrading the toxic 3,4-dihydroxybenzoic acid (3,4-DHBA) pollutant in water. The F-MWCNTs had a maximum 3,4-POD loading of 1060 μg/mg. Immobilized 3,4 POD had 44% of relative structural changes to its free configurations. Nevertheless, >90% of relative activity and about 50% of catalytic efficiency were retained to the free enzyme. Immobilized 3,4-POD demonstrated higher alkaline stability and thermostability than the free 3,4-POD. The free and immobilized 3,4-POD lost 82% and 66% of relative activities, respectively after 180 min of incubations at 90 °C. Excellent shelf-life was observed for the immobilized 3,4-POD with residual activity of 56% compared with 41% and 39% of the free 3,4-POD at 4 °C and 25 °C over 30 days storage. Immobilized 3,4-POD showed >60% of catalytic activity retention even after ten-cycle uses, defraying the expenses of free 3,4-POD productions for long term uses. Finally, the immobilized 3,4-POD removed 71% of 3,4-DHBA from water in <4 h, paving its future application for water purification with reduced costs and time.
Das, Rasel; Hamid, Sharifah Bee Abd; Annuar, Mohamad Suffian Mohamad
2016-01-01
The present study reported for the first time covalent immobilization of protocatechuate 3,4-dioxygenase (3,4-POD) onto functionalized multi-walled carbon nanotubes (F-MWCNT) for degrading the toxic 3,4-dihydroxybenzoic acid (3,4-DHBA) pollutant in water. The F-MWCNTs had a maximum 3,4-POD loading of 1060 μg/mg. Immobilized 3,4 POD had 44% of relative structural changes to its free configurations. Nevertheless, >90% of relative activity and about 50% of catalytic efficiency were retained to the free enzyme. Immobilized 3,4-POD demonstrated higher alkaline stability and thermostability than the free 3,4-POD. The free and immobilized 3,4-POD lost 82% and 66% of relative activities, respectively after 180 min of incubations at 90 °C. Excellent shelf-life was observed for the immobilized 3,4-POD with residual activity of 56% compared with 41% and 39% of the free 3,4-POD at 4 °C and 25 °C over 30 days storage. Immobilized 3,4-POD showed >60% of catalytic activity retention even after ten-cycle uses, defraying the expenses of free 3,4-POD productions for long term uses. Finally, the immobilized 3,4-POD removed 71% of 3,4-DHBA from water in <4 h, paving its future application for water purification with reduced costs and time. PMID:27721429
Meng, Fanli; Yang, Mingyu; Li, Yang; Li, Tianyu; Liu, Xinxin; Wang, Guoyue; Wang, Zhanchun; Jin, Xianhao; Li, Wenbin
2018-01-01
RNA interference (RNAi) is useful for controlling pests of agriculturally important crops. The soybean pod borer (SPB) is the most important soybean pest in Northeastern Asia. In an earlier study, we confirmed that the SPB could be controlled via transgenic plant-mediated RNAi. Here, the SPB transcriptome was sequenced to identify RNAi-related genes, and also to establish an RNAi-of-RNAi assay system for evaluating genes involved in the SPB systemic RNAi response. The core RNAi genes, as well as genes potentially involved in double-stranded RNA (dsRNA) uptake were identified based on SPB transcriptome sequences. A phylogenetic analysis and the characterization of these core components as well as dsRNA uptake related genes revealed that they contain conserved domains essential for the RNAi pathway. The results of the RNAi-of-RNAi assay involving Laccas e 2 (a critical cuticle pigmentation gene) as a marker showed that genes encoding the sid-like ( Sil1 ), scavenger receptor class C ( Src ), and scavenger receptor class B ( Srb3 and Srb4 ) proteins of the endocytic pathway were required for SPB cellular uptake of dsRNA. The SPB response was inferred to contain three functional small RNA pathways (i.e., miRNA, siRNA, and piRNA pathways). Additionally, the SPB systemic RNA response may rely on systemic RNA interference deficient transmembrane channel-mediated and receptor-mediated endocytic pathways. The results presented herein may be useful for developing RNAi-mediated methods to control SPB infestations in soybean.
Meng, Fanli; Yang, Mingyu; Li, Yang; Li, Tianyu; Liu, Xinxin; Wang, Guoyue; Wang, Zhanchun; Jin, Xianhao; Li, Wenbin
2018-01-01
RNA interference (RNAi) is useful for controlling pests of agriculturally important crops. The soybean pod borer (SPB) is the most important soybean pest in Northeastern Asia. In an earlier study, we confirmed that the SPB could be controlled via transgenic plant-mediated RNAi. Here, the SPB transcriptome was sequenced to identify RNAi-related genes, and also to establish an RNAi-of-RNAi assay system for evaluating genes involved in the SPB systemic RNAi response. The core RNAi genes, as well as genes potentially involved in double-stranded RNA (dsRNA) uptake were identified based on SPB transcriptome sequences. A phylogenetic analysis and the characterization of these core components as well as dsRNA uptake related genes revealed that they contain conserved domains essential for the RNAi pathway. The results of the RNAi-of-RNAi assay involving Laccase 2 (a critical cuticle pigmentation gene) as a marker showed that genes encoding the sid-like (Sil1), scavenger receptor class C (Src), and scavenger receptor class B (Srb3 and Srb4) proteins of the endocytic pathway were required for SPB cellular uptake of dsRNA. The SPB response was inferred to contain three functional small RNA pathways (i.e., miRNA, siRNA, and piRNA pathways). Additionally, the SPB systemic RNA response may rely on systemic RNA interference deficient transmembrane channel-mediated and receptor-mediated endocytic pathways. The results presented herein may be useful for developing RNAi-mediated methods to control SPB infestations in soybean. PMID:29773992
Ecological risk study on subacute toxicology experiment of streptomycin wastewater for Zebrafish
NASA Astrophysics Data System (ADS)
Shi, Qing; Shen, Hongyan
2017-08-01
An exposure experiment was conducted to study the effect of different volume fraction of effluent streptomycin wastewater on the activity of the peroxidase (POD) activity and the malondialdehyde (MDA) content in muscles of Zebrafish for 20 days. The results show that POD activity is significantly induced on the eighth day. POD activities in the muscles of Zebrafish exposed to the streptomycin wastewater of 20% exposure group were significantly different (0.01
Osawa, Gakuji; Yoshimatsu, Kazuhiko; Yokomizo, Hajime; Otani, Taisuke; Matsumoto, Atsuo; Nakayama, Mao; Ogawa, Kenji
2015-06-01
We analyzed the effects of the Kampo medicine "Dai-kenchu-to" (DKT) on clinical aspects in colorectal surgery. Total 122 patients who underwent colorectal cancer surgery were divided into a DKT group (n = 53) and a non-DKT group (n = 69). The differences of postoperative course and anti-inflammatory responses between those two groups were analyzed. The 53 out of 59 patients could completely take DKT. In the postoperative course, significant difference was observed in the first flatus day. In the anti-inflammatory effects, differences were observed in the heart rate (HR) of the 3rd POD. In the change between 1st POD and 3rd POD, HR in the DKT group was well controlled compared to the non-DKT group. In the patients who had over 37.5°C of body temperature in 1st POD (n = 53), inflammatory response of the DKT group was reduced compared to the non-DKT group. The DKT might have the favorable influences on postoperative bowel movement and systemic inflammatory reaction, and induce the better postoperative course.
NASA Astrophysics Data System (ADS)
Hillenbrand, Christopher F.
1995-03-01
A submarine trails one fiber optic cable and an undersea vehicle is controlled by this first cable. A missile/torpedo trails a second cable that is to be coupled to the first cable. The second cable has a segment suspended vertically underwater between a buoyant pod and a sea anchor type buoy. The undersea vehicle, or autonomous undersea vehicle, (AUV) hunts for the pod by conventional homing components, and cable capturing arms on the vehicle direct the cable's movement relative to the vehicle into a pod mating position that achieves optical coupling of the two cables. In one embodiment two arms are pivotably mounted to the vehicle's sides so one arm captures the suspended cable segment directing it into a slot so a male socket in the underside of the pod mates with a female socket in the slot. Another embodiment accomplishes the same result with a device in which the arms are formed as the off-shoots of a forked cable pickup device in the nose of the AUV.
Craig, D G; Lee, P; Pryde, E A; Hayes, P C; Simpson, K J
2013-12-01
Macrophage activation is implicated in the pathogenesis of the systemic inflammatory response syndrome (SIRS) following paracetamol (acetaminophen) overdose (POD). Neopterin is synthesised from macrophages and reflects the intensity of monocyte/macrophage activation. Soluble CD163 (sCD163) is a marker of alternatively activated M2 macrophages. To examine neopterin and sCD163 levels in a cohort of acute liver injury patients. Consecutive patients (n = 41, (18 (43.9%) male) with acute liver injury were enrolled. Neopterin and sCD163 levels were measured by ELISA. A total of 24/33 (72.7%) POD patients developed hepatic encephalopathy (HE), and therefore acute liver failure. Both neopterin and sCD163 levels were significantly higher in PODs compared with chronic liver disease (neopterin P < 0.001, sCD163 P = 0.038) and healthy (both P < 0.001) controls. Admission neopterin levels were significantly higher in PODs: with HE (P = 0.001); with the SIRS (P = 0.005); who required renal replacement therapy (P = 0.003); who died or required liver transplantation (P = 0.006; AUROC 78.6% (95% CI 62.2-94.9%). Serum sCD163 levels were significantly higher in those PODs with the SIRS (P = 0.033) on admission, and were higher in those PODs who died or required OLT (P = 0.024). Both admission neopterin and sCD163 levels in PODs correlated with organ failure scores but not with serum ALT. There was no significant correlation between neopterin and sCD163 values. Both serum neopterin and sCD163 levels are significantly elevated following paracetamol overdose, and reflect the degree of macrophage activation in this condition. Serum neopterin in particular may have value as an early proxy marker of macrophage activation following paracetamol overdose. © 2013 John Wiley & Sons Ltd.
Rebmann, Terri; Anthony, John; Loux, Travis M; Mulroy, Julia; Sitzes, Rikki
Little is known about closed point-of-dispensing (POD) site preparedness-especially how these entities progress in their preparedness efforts over time. The purpose of this study was to assess the preparedness of a closed POD network. Between 2012 and 2016, 30% to 50% of POD entities in the St. Louis County region were assessed each year, for a total of 138 site evaluations from 62 entities. The assessment tool included 41 components of closed POD preparedness, each scored either 0 = not met or 1 = met. POD preparedness scores could range from 0 to 41. Chi-square tests were conducted to compare the percentage of entities that had each preparedness indicator. A multilevel linear model with a random intercept for each agency was used to model longitudinal changes in closed POD preparedness. POD preparedness scores were higher in 2016 than in 2012 (31.5 vs. 26.5, t = 14.3, p < .001); however, there was a negative yearly trend in preparedness, and, on average, entities met only 65.4% of the preparedness indicators. Only a third of entities reported hosting a POD exercise at least once every 2 years (32.3%, n = 20). From the multilevel regression, determinants of better POD preparedness include having been assessed more often, employing a business continuity expert, and not being a long-term care agency. Closed POD entities should continue to work toward better preparedness, to better ensure successful deployment. Findings from this study indicate that more frequent assessments likely enhance preparedness at closed POD entities.
Analysis of HY2A precise orbit determination using DORIS
NASA Astrophysics Data System (ADS)
Gao, Fan; Peng, Bibo; Zhang, Yu; Evariste, Ngatchou Heutchi; Liu, Jihua; Wang, Xiaohui; Zhong, Min; Lin, Mingsen; Wang, Nazi; Chen, Runjing; Xu, Houze
2015-03-01
HY2A is the first Chinese marine dynamic environment satellite. The payloads include a radar altimeter to measure the sea surface height in combination with a high precision orbit to be determined from tracking data. Onboard satellite tracking includes GPS, SLR, and the DORIS DGXX receiver which delivers phase and pseudo-range measurements. CNES releases raw phase and pseudo-range measurements with RINEX DORIS 3.0 format and pre-processed Doppler range-rate with DORIS 2.2 data format. However, the VMSI software package developed by Van Martin Systems, Inc which is used to estimate HY2A DORIS orbits can only process Doppler range-rate but not the DORIS phase data which are available with much shorter latency. We have proposed a method of constructing the phase increment data, which are similar to range-rate data, from RINEX DORIS 3.0 phase data. We compute the HY2A orbits from June, 2013 to August, 2013 using the POD strategy described in this paper based on DORIS 2.2 range-rate data and our reconstructed phase increment data. The estimated orbits are evaluated by comparing with the CNES precise orbits and SLR residuals. Our DORIS-only orbits agree with the precise GPS + SLR + DORIS CNES orbits radially at 1-cm and about 3-cm in the other two directions. SLR test with the 50° cutoff elevation shows that the CNES orbit can achieve about 1.1-cm accuracy in radial direction and our DORIS-only POD solutions are slightly worse. In addition, other HY2A DORIS POD concerns are discussed in this paper. Firstly, we discuss the frequency offset values provided with the RINEX data and find that orbit accuracy for the case when the frequency offset is applied is worse than when it is not applied. Secondly, HY2A DORIS antenna z-offsets are estimated using two kinds of measurements from June, 2013 to August, 2013. The results show that the measurement errors contribute a total of about 2-cm difference of estimated z-offset. Finally, we estimate HY2A orbits selecting 3 days with severe geomagnetic storm activity and SLR residuals suggest that estimating a drag coefficient every 6 h without any constraint is sufficient for maintaining orbit accuracy.
Mass prophylaxis dispensing concerns: traffic and public access to PODs.
Baccam, Prasith; Willauer, David; Krometis, Justin; Ma, Yongchang; Sen, Atri; Boechler, Michael
2011-06-01
The ability to quickly dispense postexposure prophylaxis (PEP) using multiple points of dispensing (PODs) following a bioterrorism event could potentially save a large proportion of those who were exposed, while failure in PEP dispensing could have dire public health consequences. A Monte Carlo simulation was developed to explore the traffic flow and parking around PODs under different arrival rates and how these factors might affect the utilization rate of POD workers. The results demonstrate that the public can reasonably access the PODs under ideal conditions assuming a stationary (uniform) arrival rate. For the 5 nonstationary arrival rates tested, however, the available parking spaces quickly become filled, causing long traffic queues and resulting in total processing times that range from 1 hour to over 6 hours. Basic planning considerations should include the use of physical barriers, signage, and traffic control officers to help direct vehicular and pedestrian access to the PODs. Furthermore, the parking and traffic surrounding PODs creates long queues of people waiting to access the PODs. Thus, POD staff are fully used approximately 90% of the time, which can lead to worker fatigue and burn out.
Validation of a White-light 3D Body Volume Scanner to Assess Body Composition.
Medina-Inojosa, Jose; Somers, Virend; Jenkins, Sarah; Zundel, Jennifer; Johnson, Lynne; Grimes, Chassidy; Lopez-Jimenez, Francisco
2017-01-01
Estimating body fat content has shown to be a better predictor of adiposity-related cardiovascular risk than the commonly used body mass index (BMI). The white-light 3D body volume index (BVI) scanner is a non-invasive device normally used in the clothing industry to assess body shapes and sizes. We assessed the hypothesis that volume obtained by BVI is comparable to the volume obtained by air displacement plethysmography (Bod-Pod) and thus capable of assessing body fat mass using the bi-compartmental principles of body composition. We compared BVI to Bod-pod, a validated bicompartmental method to assess body fat percent that uses pressure/volume relationships in isothermal conditions to estimate body volume. Volume is then used to calculate body density (BD) applying the formula density=Body Mass/Volume. Body fat mass percentage is then calculated using the Siri formula (4.95/BD - 4.50) × 100. Subjects were undergoing a wellness evaluation. Measurements from both devices were obtained the same day. A prediction model for total Bod-pod volume was developed using linear regression based on 80% of the observations (N=971), as follows: Predicted Bod-pod Volume (L)=9.498+0.805*(BVI volume, L)-0.0411*(Age, years)-3.295*(Male=0, Female=1)+0.0554*(BVI volume, L)*(Male=0, Female=1)+0.0282*(Age, years)*(Male=0, Female=1). Predictions for Bod-pod volume based on the estimated model were then calculated for the remaining 20% (N=243) and compared to the volume measured by the Bod-pod. Mean age among the 971 individuals was 41.5 ± 12.9 years, 39.4% were men, weight 81.6 ± 20.9 kg, BMI was 27.8 ± 6.3kg/m 2 . Average difference between volume measured by Bod-pod- predicted volume by BVI was 0.0 L, median: -0.4 L, IQR: -1.8 L to 1.5 L, R2=0.9845. Average difference between body fat measured-predicted was-1%, median: -2.7%, IQR: -13.2 to 9.9, R2=0.9236. Volume and BFM can be estimated by using volume measurements obtained by a white- light 3D body scanner and the prediction model developed in this study.
Tamura, M; Kanno, Y; Chuma, S; Saito, T; Nakatsuji, N
2001-04-01
Mammalian sex-determination and differentiation are controlled by several genes, such as Sry, Sox-9, Dax-1 and Mullerian inhibiting substance (MIS), but their upstream and downstream genes are largely unknown. Ad4BP/SF-1, encoding a zinc finger transcription factor, plays important roles in gonadogenesis. Disruption of this gene caused disappearance of the urogenital system including the gonad. Ad4BP/SF-1, however, is also involved in the sex differentiation of the gonad at later stages, such as the regulation of steroid hormones and MIS. Pod-1/Capsulin, a member of basic helix-loop-helix transcription factors, is expressed in a pattern closely related but mostly complimentary to that of the Ad4BP/SF-1 expression in the developing gonad. In the co-transfection experiment using cultured cells, overexpression of Pod-1/Capsulin repressed expression of a reporter gene that carried the upstream regulatory region of the Ad4BP/SF-1 gene. Furthermore, forced expression of Pod-1/Capsulin repressed expression of Ad4BP/SF-1 in the Leydig cell-derived I-10 cells. These results suggest that Pod-1/Capsulin may play important roles in the development and sex differentiation of the mammalian gonad via transcriptional regulation of Ad4BP/SF-1.
CSENDES J., Attila; MUÑOZ Ch., Andrea; BURGOS L., Ana María
2014-01-01
Background The complete blood count (CBC) and C-reactive protein (CRP) are useful inflammatory parameters for ruling out acute postoperative inflammatory complications. Aim To determine their changes in gastric cancer patients submitted to total gastrectomy. Methods This is a prospective study, with 36 patients with gastric cancer who were submitted to elective total gastrectomy. On the first, third and fifth postoperative day (POD), blood count and CRP changes were assessed. Patients with postoperative complications were excluded. Results Twenty-one (58%) were men and 15 (42%) women. The mean age was 65 years. The leukocytes peaked on the 1st POD with a mean of 13,826 u/mm³, and decreased to 8,266 u/mm³ by the 5th POD. The bacilliforms peaked on the 1st POD with a maximum value of 1.48%. CRP reached its maximum level on the 3rd POD with a mean of 144.64 mg/l±44.84. Preoperative hematocrit (HCT) was 35% and 33.67% by the 5th POD. Hemoglobin, showed similar values. Conclusions Leukocytes increased during the 1st POD but reached normal values by the 5th POD. CRP peaked on the 3rd POD but did not reach normal values by the 5th POD. PMID:25626929
POD Analysis of Jet-Plume/Afterbody-Wake Interaction
NASA Astrophysics Data System (ADS)
Murray, Nathan E.; Seiner, John M.; Jansen, Bernard J.; Gui, Lichuan; Sockwell, Shuan; Joachim, Matthew
2009-11-01
The understanding of the flow physics in the base region of a powered rocket is one of the keys to designing the next generation of reusable launchers. The base flow features affect the aerodynamics and the heat loading at the base of the vehicle. Recent efforts at the National Center for Physical Acoustics at the University of Mississippi have refurbished two models for studying jet-plume/afterbody-wake interactions in the NCPA's 1-foot Tri-Sonic Wind Tunnel Facility. Both models have a 2.5 inch outer diameter with a nominally 0.5 inch diameter centered exhaust nozzle. One of the models is capable of being powered with gaseous H2 and O2 to study the base flow in a fully combusting senario. The second model uses hi-pressure air to drive the exhaust providing an unheated representative flow field. This unheated model was used to acquire PIV data of the base flow. Subsequently, a POD analysis was performed to provide a first look at the large-scale structures present for the interaction between an axisymmetric jet and an axisymmetric afterbody wake. PIV and Schlieren data are presented for a single jet-exhaust to free-stream flow velocity along with the POD analysis of the base flow field.
Karim, Azila Abdul; Azlan, Azrina; Ismail, Amin; Hashim, Puziah; Abd Gani, Siti Salwa; Zainudin, Badrul Hisyam; Abdullah, Nur Azilah
2014-10-07
Cocoa pod is an outer part of cocoa fruits being discarded during cocoa bean processing. Authors found out that data on its usage in literature as cosmetic materials was not recorded in vast. In this study, cocoa pod extract was investigated for its potential as a cosmetic ingredient. Cocoa pod extract (CPE) composition was accomplished using UHPLC. The antioxidant capacity were measured using scavenging assay of 1,2-diphenyl-2-picrylhydrazyl (DPPH), β-carotene bleaching assay (BCB) and ferric reducing antioxidant power (FRAP). Inhibiting effect on skin degradation enzymes was carried out using elastase and collagenase assays. The skin whitening effect of CPE was determined based on mushroom tyrosinase assay and sun screening effect (UV-absorbance at 200-400 nm wavelength). LC-MS/MS data showed the presence of carboxylic acid, phenolic acid, fatty acid, flavonoids (flavonol and flavones), stilbenoids and terpenoids in CPE. Results for antioxidant activity exhibited that CPE possessed good antioxidant activity, based on the mechanism of the assays compared with ascorbic acid (AA) and standardized pine bark extract (PBE); DPPH: AA > CPE > PBE; FRAP: PBE > CPE > AA; and BCB: BHT > CPE > PBE. Cocoa pod extract showed better action against elastase and collagenase enzymes in comparison with PBE and AA. Higher inhibition towards tyrosinase enzyme was exhibited by CPE than kojic acid and AA, although lower than PBE. CPE induced proliferation when tested on human fibroblast cell at low concentration. CPE also exhibited a potential as UVB sunscreen despite its low performance as a UVA sunscreen agent. Therefore, the CPE has high potential as a cosmetic ingredient due to its anti-wrinkle, skin whitening, and sunscreen effects.
Anthocyanins and flavonols are responsible for purple color of Lablab purpureus (L.) sweet pods.
Cui, Baolu; Hu, Zongli; Zhang, Yanjie; Hu, Jingtao; Yin, Wencheng; Feng, Ye; Xie, Qiaoli; Chen, Guoping
2016-06-01
Lablab pods, as dietary vegetable, have high nutritional values similar to most of edible legumes. Moreover, our studies confirmed that purple lablab pods contain the natural pigments of anthocyanins and flavonols. Compared to green pods, five kinds of anthocyanins (malvidin, delphinidin and petunidin derivatives) were found in purple pods by HPLC-ESI-MS/MS and the major contents were delphinidin derivatives. Besides, nine kinds of polyphenol derivatives (quercetin, myricetin, kaempferol and apigenin derivatives) were detected by UPLC-ESI-MS/MS and the major components were quercetin and myricetin derivatives. In order to discover their molecular mechanism, expression patterns of biosynthesis and regulatory gens of anthocyanins and flavonols were investigated. Experimental results showed that LpPAL, LpF3H, LpF3'H, LpDFR, LpANS and LpPAP1 expressions were significantly induced in purple pods compared to green ones. Meanwhile, transcripts of LpFLS were more abundant in purple pods than green or yellow ones, suggestind that co-pigments of anthocyanins and flavonols are accumulated in purple pods. Under continuously dark condition, no anthocyanin accumulation was detected in purple pods and transcripts of LpCHS, LpANS, LpFLS and LpPAP1 were remarkably repressed, indicating that anthocyanins and flavonols biosynthesis in purple pods was regulated in light-dependent manner. These results indicate that co-pigments of anthocyanins and flavonols contribute to purple pigmentations of pods. Copyright © 2016 Elsevier Masson SAS. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Heitholt, J.J.
Soybeans (Glycine max (L.) Merr.) were grown in the field in 1982 and 1983 (cv. Kent) and greenhouse (cv. McCall) to characterize the effects of timing and source-sink alterations on flower and immature pod abortion and to study the causes of abortion. Flowers and immature pods were marked during early flowering (R1 to R2) and late flowering (R3 to R4). Nineteen percent of the early flowers aborted in the greenhouse and 31 to 48% aborted in the field. Seventy-six to 92% and 77 to 90% of the late flowers aborted in the greenhouse and field, respectively. Defoliation increased early flowermore » abortion and depodding decreased late flower abortion. Fifteen and 19% of the early immature pods and the late immature pods from depodded plants aborted, respectively. Fifty-seven percent of the late immature pods aborted. Across both years there was not a consistent relationship between the concentrations of ethanol soluble carbohydrates, starch, ethanol soluble nitrogen, ethanol insoluble nitrogen, nitrate, and cations in the flowers or immature pods and abortion. During both early and late flowering, a single leaf located in the middle of the main stem that subtended flowers at anthesis, or immature pods was labeled with 3.7 x 10/sup 5/ Bq /sup 14/CO/sub 2/ for 1 h. After 24 h the entire plant was harvested, divided into flowers, pods, labeled leaf, and the remainder of the plant and the radioactivity was determined. The low aborting flowers and immature pods contained a greater percentage of the total /sup 14/C recovered than the high aborting flowers and immature pods. The results indirectly support the hypothesis that a signal compound produced by another plant part, perhaps the established pods, inhibits the development of aborting flowers and immature pods.« less
Cakir, Tebessum; Ozer, Ilter; Bostanci, Erdal Birol; Keklik, Tulay Timucin; Ercin, Ugur; Bilgihan, Ayse; Akoglu, Musa
2015-01-01
Inadequate healing and high anastomosis leak rates at rectal anastomosis may be due to lack of supportive serosal layer and technical difficulty of low anterior resections. Positive effects of sildenafil on wound healing were observed. The aim of this study was to simulate rectal anastomosis as a technical insufficient anastomosis and investigate the effects of sildenafil on anastomosis healing. Colonic anastomoses were carried out in 64 rats and randomized into four groups, CA-S, complete anastomoses without sildenafil (10 mg/kg for 5 days); CA+S, complete anastomoses with sildenafil; IA-S, incomplete anastomoses without sildenafil; IA+S, incomplete anastomoses with sildenafil. Half of the rats in every group were sacrificed on post-operative day (POD) 3, half of them sacrificed on POD 7. Tissues from the anastomoses were used for functional, histochemical, biochemical investigations. Sildenafil treatment resulted in increased bursting pressures in IA+S on POD 7 (p=0.010). Collagen maturity was higher in IA+S on POD 3 and POD 7, CA+S on POD 7 (p=0.010; p=0.010; p<0.007). Collagen content was higher in IA+S on POD 7 (p<0.001). Glutathione, hydroxyproline levels were similar. Malondialdehyde levels were lower in IA+S on POD 3 (p<0.001). Epithelization score was higher in IA+S on POD 7 (p=0.007). Inflammation score was higher in CA-S group on POD 3 and POD 7 (p<0.001; p<0.001). Neutrophil score was lower in CA+S on POD 3 (p=0.005). An increase in collagen content, maturity, and epithelization, a decrease in neutrophil infiltration, oxidative stress and better mechanical strength were observed with the administration of sildenafil. Copyright © 2014 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.
500 Women Scientists: Science Advocacy Through Community Action
NASA Astrophysics Data System (ADS)
Bohon, W.; Bartel, B. A.; Pendergrass, A. G.; Ramirez, K. S.; Vijayaraghavan, R.; Weintraub, S. R.; Zelikova, T. J.
2017-12-01
500 Women Scientists is a grassroots organization formed in late 2016 to empower women to grow to their full potential in science, increase scientific literacy through public engagement, and advocate for science and equality. Our organization is global but we focus on building community relationships through local action. Our "pods," or local chapters, focus on issues that resonate in their communities, rooted in our mission and values. Pod members meet regularly, develop a support network, make strategic plans, and take action. In less than a year, 500 Women Scientists has already formed important partnerships and begun to work on local, regional and national projects. Nationally, we partnered with The Cairn Project to raise money to support girls in science. In an effort led by the DC pod, our members sent postcards sharing stories of how the EPA protects their communities in the #OurEPA postcard campaign. Pods have also participated in marches, including the Women's March, the March for Science and the People's Climate March. The "Summer of Op-Ed" campaign catalyzed pods and individuals to write to their local newspapers to speak up for funding science, climate change action, and general science advocacy. We have organized "strike-teams" that are working on local issues like education, the environment, climate change, and equal access to science. Additionally, pod members serve as mentors, participate in local events, hold workshops and partner with local organizations. As women scientists, we are in the position to take action to increase diversity in science and to draw attention to unacknowledged structural biases that negatively impact historically under-represented groups. 500 Women Scientists enables women in science to embrace this advocacy role, both within our scientific system and within our local communities.
Schweiggert, Ute; Kammerer, Dietmar R; Carle, Reinhold; Schieber, Andreas
2005-01-01
Carotenoids and carotenoid esters were extracted from red pepper pods (Capsicum annuum L.) without saponification. Among the 42 compounds detected, 4 non-esterified, 11 mono- and 17 diesters were characterized based on their retention times, UV/Vis spectra and their fragmentation patterns in collision-induced dissociation experiments in atmospheric pressure chemical ionization mass spectrometry (APCI-MS). Positive and negative ion mode measurements were used for the characterization of major and minor carotenoids and their esters. Capsanthin esterified with lauric, palmitic and myristic acids represented the predominant compounds in the red pepper extracts. Additionally, three beta-cryptoxanthin and one zeaxanthin monoester were tentatively identified in red pepper pods for the first time. Furthermore, the specific fragmentation patterns of capsanthin-laurate-myristate and capsanthin-myristate-palmitate were used for the distinction of both regioisomers. The results obtained from LC-DAD-APCI-MSn experiments demonstrated that the carotenoid profile of red pepper pods is considerably more complex than considered hitherto. Copyright (c) 2005 John Wiley & Sons, Ltd.
New features of triacylglycerol biosynthetic pathways of peanut seeds in early developmental stages.
Yu, Mingli; Liu, Fengzhen; Zhu, Weiwei; Sun, Meihong; Liu, Jiang; Li, Xinzheng
2015-11-01
The peanut (Arachis hypogaea L.) is one of the three most important oil crops in the world due to its high average oil content (50 %). To reveal the biosynthetic pathways of seed oil in the early developmental stages of peanut pods with the goal of improving the oil quality, we presented a method combining deep sequencing analysis of the peanut pod transcriptome and quantitative real-time PCR (RT-PCR) verification of seed oil-related genes. From the sequencing data, approximately 1500 lipid metabolism-associated Unigenes were identified. The RT-PCR results quantified the different expression patterns of these triacylglycerol (TAG) synthesis-related genes in the early developmental stages of peanut pods. Based on these results and analysis, we proposed a novel construct of the metabolic pathways involved in the biosynthesis of TAG, including the Kennedy pathway, acyl-CoA-independent pathway and proposed monoacylglycerol pathway. It showed that the biosynthetic pathways of TAG in the early developmental stages of peanut pods were much more complicated than a simple, unidirectional, linear pathway.
Brunel-Muguet, Sophie; Mollier, Alain; Kauffmann, François; Avice, Jean-Christophe; Goudier, Damien; Sénécal, Emmanuelle; Etienne, Philippe
2015-01-01
Sulfur (S) nutrition in rapeseed (Brassica napus L.) is a major concern for this high S-demanding crop, especially in the context of soil S oligotrophy. Therefore, predicting plant growth, S plant allocation (between the plant’s compartments) and S pool partitioning (repartition of the mobile-S vs. non-mobile-S fractions) until the onset of reproductive phase could help in the diagnosis of S deficiencies during the early stages. For this purpose, a process-based model, SuMoToRI (Sulfur Model Toward Rapeseed Improvement), was developed up to the onset of pod formation. The key features rely on (i) the determination of the S requirements used for growth (structural and metabolic functions) through critical S dilution curves and (ii) the estimation of a mobile pool of S that is regenerated by daily S uptake and remobilization from senescing leaves. This study describes the functioning of the model and presents the model’s calibration and evaluation. SuMoToRI was calibrated and evaluated with independent datasets from greenhouse experiments under contrasting S supply conditions. It is run with a small number of parameters with generic values, except in the case of the radiation use efficiency, which was shown to be modulated by S supply. The model gave satisfying predictions of the dynamics of growth, S allocation between compartments and S partitioning, such as the mobile-S fraction in the leaves, which is an indicator of the remobilization potential toward growing sinks. The mechanistic features of SuMoToRI provide a process-based framework that has enabled the description of the S remobilizing process in a species characterized by senescence during the vegetative phase. We believe that this model structure could be useful for modeling S dynamics in other arable crops that have similar senescence-related characteristics. PMID:26635825
PCVs Estimation and their Impacts on Precise Orbit Determination of LEOs
NASA Astrophysics Data System (ADS)
Chunmei, Z.; WANG, X.
2017-12-01
In the last decade the precise orbit determination (POD) based on GNSS, such as GPS, has been considered as one of the efficient methods to derive orbits of Low Earth Orbiters (LEOs) that demand accuracy requirements. The Earth gravity field recovery and its related researches require precise dynamic orbits of LEOs. With the improvements of GNSS satellites' orbit and clock accuracy, the algorithm optimization and the refinement of perturbation force models, the antenna phase-center variations (PCVs) of space-borne GNSS receiver have become an increasingly important factor that affects POD accuracy. A series of LEOs such as HY-2, ZY-3 and FY-3 with homebred space-borne GNSS receivers have been launched in the past several years in China. Some of these LEOs load dual-mode GNSS receivers of GPS and BDS signals. The reliable performance of these space-borne receivers has been establishing an important foundation for the future launches of China gravity satellites. Therefore, we first evaluate the data quality of on-board GNSS measurement by examining integrity, multipath error, cycle slip ratio and other quality indices. Then we determine the orbits of several LEOs at different altitudes by the reduced dynamic orbit determination method. The corresponding ionosphere-free carrier phase post-fit residual time series are obtained. And then we establish the PCVs model by the ionosphere-free residual approach and analyze the effects of antenna phase-center variation on orbits. It is shown that orbit accuracy of LEO satellites is greatly improved after in-flight PCV calibration. Finally, focus on the dual-mode receiver of FY-3 satellite we analyze the quality of onboard BDS data and then evaluate the accuracy of the FY-3 orbit determined using only BDS measurement onboard. The accuracy of LEO satellites orbit based on BDS would be well improved with the global completion of BDS by 2020.
Application of rape pod sealants to reduce adverse environmental impacts.
Bauša, Laimis; Steponavičius, Dainius; Jotautienė, Eglė; Kemzūraitė, Aurelija; Zaleckas, Ernestas
2018-04-01
Rape (Brassica napus L.) is a major global oilseed crop characterized by its high potential as an alimentary oil and in biodiesel production. The two most popular pod sealants (PS) used to reduce rape pod shattering are products in the pinolene range (di-1-p-menthene) and latex polymer products. Reports on the effective preservation of seed yield by these products are fairly contradictory. With this in mind, an experimental PS (PS4) that contained the active agents acrylic and trisiloxane was developed. Comparative experimental trials of the developed PS4 and three other PS (PS1, PS2 and PS3) containing active agents that are generally used for sealant production were conducted. The studies showed that the static and dynamic surface tension of PS4 was the lowest at the same concentration (2.0 g kg -1 ), consequently demonstrating the lowest spray drift. The chemical substances from PS had not penetrated the rape seeds in any of the PSs. The results indicate that treatment with PS4 exerts a beneficial effect in reducing rape seed yield loss (68-104 kg ha -1 in 2014 and 194-305 kg ha -1 in 2015) compared to other investigated PS. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.
Investigation of coherent structures in a superheated jet using decomposition methods
NASA Astrophysics Data System (ADS)
Sinha, Avick; Gopalakrishnan, Shivasubramanian; Balasubramanian, Sridhar
2016-11-01
A superheated turbulent jet, commonly encountered in many engineering flows, is complex two phase mixture of liquid and vapor. The superposition of temporally and spatially evolving coherent vortical motions, known as coherent structures (CS), govern the dynamics of such a jet. Both POD and DMD are employed to analyze such vortical motions. PIV data is used in conjunction with the decomposition methods to analyze the CS in the flow. The experiments were conducted using water emanating into a tank containing homogeneous fluid at ambient condition. Three inlet pressure were employed in the study, all at a fixed inlet temperature. 90% of the total kinetic energy in the mean flow is contained within the first five modes. The scatterplot for any two POD coefficients predominantly showed a circular distribution, representing a strong connection between the two modes. We speculate that the velocity and vorticity contours of spatial POD basis functions show presence of K-H instability in the flow. From DMD, eigenvalues away from the origin is observed for all the cases indicating the presence of a non-oscillatory structure. Spatial structures are also obtained from DMD. The authors are grateful to Confederation of Indian Industry and General Electric India Pvt. Ltd. for partial funding of this project.
Probabilistic Fracture Mechanics Analysis of the Orbiter's LH2 Feedline Flowliner
NASA Technical Reports Server (NTRS)
Bonacuse, Peter J. (Technical Monitor); Hudak, Stephen J., Jr.; Huyse, Luc; Chell, Graham; Lee, Yi-Der; Riha, David S.; Thacker, Ben; McClung, Craig; Gardner, Brian; Leverant, Gerald R.;
2005-01-01
Work performed by Southwest Research Institute (SwRI) as part of an Independent Technical Assessment (ITA) for the NASA Engineering and Safety Center (NESC) is summarized. The ITA goal was to establish a flight rationale in light of a history of fatigue cracking due to flow induced vibrations in the feedline flowliners that supply liquid hydrogen to the space shuttle main engines. Prior deterministic analyses using worst-case assumptions predicted failure in a single flight. The current work formulated statistical models for dynamic loading and cryogenic fatigue crack growth properties, instead of using worst-case assumptions. Weight function solutions for bivariant stressing were developed to determine accurate crack "driving-forces". Monte Carlo simulations showed that low flowliner probabilities of failure (POF = 0.001 to 0.0001) are achievable, provided pre-flight inspections for cracks are performed with adequate probability of detection (POD)-specifically, 20/75 mils with 50%/99% POD. Measurements to confirm assumed POD curves are recommended. Since the computed POFs are very sensitive to the cyclic loads/stresses and the analysis of strain gage data revealed inconsistencies with the previous assumption of a single dominant vibrant mode, further work to reconcile this difference is recommended. It is possible that the unaccounted vibrational modes in the flight spectra could increase the computed POFs.
NASA Technical Reports Server (NTRS)
Porro, A. Robert
2000-01-01
One of the propulsion system concepts to be considered for the High-Speed Civil Transport (HSCT) is an underwing, dual-propulsion, pod-per-wing installation. Adverse transient phenomena such as engine compressor stall and inlet unstart could severely degrade the performance of one of these propulsion pods. The subsequent loss of thrust and increased drag could cause aircraft stability and control problems that could lead to a catastrophic accident if countermeasures are not in place to anticipate and control these detrimental transient events. Aircraft system engineers must understand what happens during an engine compressor stall and inlet unstart so that they can design effective control systems to avoid and/or alleviate the effects of a propulsion pod engine compressor stall and inlet unstart. The objective of the Inlet Unstart Propulsion Airframe Integration test program was to assess the underwing flow field of a High-Speed Civil Transport propulsion system during an engine compressor stall and subsequent inlet unstart. Experimental research testing was conducted in the 10- by 10-Foot Supersonic Wind Tunnel at the NASA Glenn Research Center at Lewis Field. The representative propulsion pod consisted of a two-dimensional, bifurcated inlet mated to a live turbojet engine. The propulsion pod was mounted below a large flat plate that acted as a wing simulator. Because of the plate s long length (nominally 10-ft wide by 18-ft long), realistic boundary layers could form at the inlet cowl plane. Transient instrumentation was used to document the aerodynamic flow-field conditions during an unstart sequence. Acquiring these data was a significant technical challenge because a typical unstart sequence disrupts the local flow field for about only 50 msec. Flow surface information was acquired via static pressure taps installed in the wing simulator, and intrusive pressure probes were used to acquire flow-field information. These data were extensively analyzed to determine the impact of the unstart transient on the surrounding flow field. This wind tunnel test program was a success, and for the first time, researchers acquired flow-field aerodynamic data during a supersonic propulsion system engine compressor stall and inlet unstart sequence. In addition to obtaining flow-field pressure data, Glenn researchers determined other properties such as the transient flow angle and Mach number. Data are still being reduced, and a comprehensive final report will be released during calendar year 2000.
Laconi, Erika B; Jayanegara, Anuraga
2015-03-01
Cocoa pod is among the by-products of cocoa (Theobroma cacao) plantations. The aim of this study was to apply a number of treatments in order to improve nutritional quality of cocoa pod for feeding of ruminants. Cocoa pod was subjected to different treatments, i.e. C (cocoa pod without any treatment or control), CAm (cocoa pod+1.5% urea), CMo (cocoa pod+3% molasses), CRu (cocoa pod+3% rumen content) and CPh (cocoa pod+3% molasses+Phanerochaete chrysosporium inoculum). Analysis of proximate and Van Soest's fiber fraction were performed on the respective treatments. The pods were then subjected to an in vitro digestibility evaluation by incubation in rumen fluid-buffer medium, employing a randomized complete block design (n = 3 replicates). Further, an in vivo evaluation of the pods (35% inclusion level in total mixed ration) was conducted by feeding to young Holstein steers (average body weight of 145±3.6 kg) with a 5×5 latin square design arrangement (n = 5 replicates). Each experimental period lasted for 30 d; the first 20 d was for feed adaptation, the next 3 d was for sampling of rumen liquid, and the last 7 d was for measurements of digestibility and N balance. Results revealed that lignin content was reduced significantly when cocoa pod was treated with urea, molasses, rumen content or P. chrysosporium (p<0.01) with the following order of effectiveness: CPh>CAm>CRu>CMo. Among all treatments, CAm and CPh treatments significantly improved the in vitro dry matter and organic matter digestibility (p<0.05) of cocoa pod. Average daily gain of steers receiving CAm or CPh treatment was significantly higher than that of control (p<0.01) with an increase of 105% and 92%, respectively. Such higher daily gain was concomitant with higher N retention and proportion of N retention to N intake in CAm and CPh treatments than those of control (p<0.05). It can be concluded from this study that treatment with either urea or P. chrysosporium is effective in improving the nutritive value of cocoa pod.
Acoustic Seaglider(trademark) for Beaked Whale Detection
2009-09-30
of all three pods of southern resident killer whales (Orcinus orca) were present at various times. SG022 completed five dives in water depths...characterize system performance. • Deploy locally in the presence of killer whales (Orcinus orca) as a proxy for beaked whales . • Deploy off Kona (west) coast...between 60m to 120m. SG022 was positioned at the start of each dive at ranges to the killer whale pods of between 0.8km and 3.5km. The PAAM board was
2017-03-01
delays. As shown, the remaining schedule was modified to allow Boeing to deliver the first 18 aircraft and pods separately by October 2018, 14...testing. Among other things, Boeing is contractually required to deliver a total of 18 aircraft and 9 wing air refueling pod sets by August 2017...Parameters and System Attributes and Status of Technical Performance Capabilities 18 Appendix II GAO Contact and Staff Acknowledgments 20 Related
Pineño, Oskar
2014-03-01
This article introduces the ArduiPod Box, an open-source device built using two main components (i.e., an iPod Touch and an Arduino microcontroller), developed as a low-cost alternative to the standard operant conditioning chamber, or "Skinner box." Because of its affordability, the ArduiPod Box provides an opportunity for educational institutions with small budgets seeking to set up animal laboratories for research and instructional purposes. A pilot experiment is also presented, which shows that the ArduiPod Box, in spite of its extraordinary simplicity, can be effectively used to study animal learning and behavior.
Concentrated liquid detergent pod ingestion in children.
Sidhu, Natasha; Jaeger, Matthew W
2014-12-01
Concentrated liquid detergent pods are an emerging public health hazard, especially in pediatric patients. Ingestion is a more common route of exposure for liquid detergent pods compared with non-pod detergents and it tends to be associated with more severe adverse effects. We present 3 cases that demonstrate the varied clinical symptoms resulting from detergent pod ingestion. These cases not only demonstrate findings such as gastrointestinal and respiratory symptoms but also show more rare neurological symptoms. The cases highlight the dangers of concentrated liquid detergent pod ingestion. To help prevent further life-threatening injuries, there is a need for more consumer information and provider knowledge about the potential adverse complications.
Khoyratty, Shahnoo; Dupont, Joëlle; Lacoste, Sandrine; Palama, Tony Lionel; Choi, Young Hae; Kim, Hye Kyong; Payet, Bertrand; Grisoni, Michel; Fouillaud, Mireille; Verpoorte, Robert; Kodja, Hippolyte
2015-06-14
The objective of the work was to characterize fungal endophytes from aerial parts of Vanilla planifolia. Also, to establish their biotransformation abilities of flavor-related metabolites. This was done in order to find a potential role of endophytes on vanilla flavors. Twenty three MOTUs were obtained, representing 6 fungal classes. Fungi from green pods were cultured on mature green pod based media for 30 days followed by (1)H NMR and HPLC-DAD analysis. All fungi from pods consumed metabolized vanilla flavor phenolics. Though Fusarium proliferatum was recovered more often (37.6% of the isolates), it is Pestalotiopsis microspora (3.0%) that increased the absolute amounts (quantified by (1)H NMR in μmol/g DW green pods) of vanillin (37.0 × 10(-3)), vanillyl alcohol (100.0 × 10(-3)), vanillic acid (9.2 × 10(-3)) and p-hydroxybenzoic acid (87.9 × 10(-3)) by significant amounts. All plants studied contained endophytic fungi and the isolation of the endophytes was conducted from plant organs at nine sites in Réunion Island including under shade house and undergrowth conditions. Endophytic variation occured between cultivation practices and the type of organ. Given the physical proximity of fungi inside pods, endophytic biotransformation may contribute to the complexity of vanilla flavors.
Machado, Nelson; Domínguez-Perles, Raúl; Ramos, Ana; Rosa, Eduardo As; Barros, Ana Irna
2017-10-01
Freezing represents an important storage method for vegetal foodstuffs, such as cowpea pods, and thus the impact of this process on the chemical composition of these matrices arises as a prominent issue. In this sense, the phytochemical contents in frozen cowpea pods (i.e. at 6 and 9 months) have been compared with fresh cowpea pods material, with the samples being concomitantly assessed by Fourier-transform infrared spectroscopy (FTIR), both mid-infrared (MIR) and near infrared (NIR), aiming to evaluate the potential of these techniques as a rapid tool for the traceability of these matrices. A decrease in phytochemical contents during freezing was observed, allowing the classification of samples according to the freezing period based on such variations. Also, MIR and NIR allowed discrimination of samples: the use of the first derivative demonstrated a better performance for this purpose, whereas the use of the normalized spectra gave the best correlations between the spectra and specific contents. In both cases, NIR displayed the best performance. Freezing of cowpea pods leads to a decrease of phytochemical contents, which can be monitored by FTIR spectroscopy, both within the MIR and NIR ranges, whereas the use of this technique, in tandem with chemometrics, constitutes a suitable methodology for the traceability of these matrices. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.
Effect of tillage system on yield and weed populations of soybean ( Glycin Max L.).
Hosseini, Seyed Z; Firouzi, Saeed; Aminpanah, Hashem; Sadeghnejhad, Hamid R
2016-03-01
Field experiment was conducted at Agricultural and Natural Resources Research Center of Golestan Province, Iran, to determine the effects of tillage system and weed management regime on yield and weed populations in soybean ( Glycin max L.). The experimental design was a split plot where the whole plot portion was a randomized complete block with three replicates. Main plots were tillage system: 1- No-till row crop seeding, 2- No-till seed drilling, 3- Tillage with disc harrow and drill planting, 4- Tillage with chisel packer and drill planting. The subplots were weed management regimes: 1-Weed control with herbicide application, 2- Hand weeding, 3- Herbicide application plus hand weeding, and 4- Non-weeding. Results indicated that the main effects of tillage system and weed management regime were significant for seed yield, pod number per plant, seed number per pod, weed density and biomass, while their interaction were significant only for weed density, weed biomass, and seed number per pod. The highest grain yields (3838 kg ha-1) were recorded for No-till row crop seeding. The highest seed yield (3877 kg ha-1) also was recorded for weed control with herbicide and hand weeding treatment, followed by hand weeding (3379 kg ha-1).
2007-09-01
curve (Smith, 2007). This curve shows the relative performance of an option based on the selected factors (Chan & Mauborgne, 2007). Value cures ...that they and their families are safe; anything less will result in staffing shortages and absenteeism . d. POD Staff Training POD volunteers would...can expect high rates of absenteeism . Local law enforcement in LAC has therefore not guaranteed one- on-one protection for the 3,750 postal carriers
Aleman-Mateo, H; Esparza Romero, J; Macias Morales, N; Salazar, G; Wyatt, J; Valencia, M E
2004-01-01
Air displacement plethysmography with the BOD-POD is a new densitometry technique, and has been found to be an accurate method to measure body composition. The aim of this study was to assess body composition in a group of free living healthy subjects 60 years of age or older from a rural area of Northwest Mexico, and to evaluate body composition by anthropometry and bioelectrical impedance (BIA) using equations reported for other elderly populations. Body composition was evaluated in 21 women and 26 men with the BOD-POD, by anthropometry, and BIA and compared to different equations using the Bland- Altman procedure. Body fat in elderly women and men was 42.7 and 30.2 % respectively. In women, Segal's equation using BIA 1, based on standing height, showed no significant differences with the BOD-POD. There was satisfactory agreement between Segal's equation and BOD-POD. In men similar results was found with Deurenberg's equation using B1A 2 based on recumbent length. Segal's and Deurenberg's equations were accurate and precise for the estimation of body fat in the elderly of this study. The use of these equations could improve the estimation of body composition for similar elderly subjects. Further studies are recommended with a larger size samples to include elderly subjects from other Latin American countries.
Fish Pectoral Fin Hydrodynamics; Part III: Low Dimensional Models via POD Analysis
NASA Astrophysics Data System (ADS)
Bozkurttas, M.; Madden, P.
2005-11-01
The highly complex kinematics of the pectoral fin and the resulting hydrodynamics does not lend itself easily to analysis based on simple notions of pitching/heaving/paddling kinematics or lift/drag based propulsive mechanisms. A more inventive approach is needed to dissect the fin gait and gain insight into the hydrodynamic performance of the pectoral fin. The focus of the current work is on the hydrodynamics of the pectoral fin of a bluegill sunfish in steady forward motion. The 3D, time-dependent fin kinematics is obtained via a stereo-videographic technique. We employ proper orthogonal decomposition to extract the essential features of the fin gait and then use CFD to examine the hydrodynamics of simplified gaits synthesized from the POD modes. The POD spectrum shows that the first two, three and five POD modes capture 55%, 67%, and 80% of the motion respectively. The first three modes are in particular highly distinct: Mode-1 is a ``cupping'' motion where the fin cups forward as it is abducted; Mode-2 is an ``expansion'' motion where the fin expands to present a larger area during adduction and finally Mode-3 involves a ``spanwise flick'' of the dorsal edge of the fin. Numerical simulation of flow past fin gaits synthesized from these modes lead to insights into the mechanisms of thrust production; these are discussed in detail.
Garcia, Sabrina O; Feltrin, Ana Carla P; Garda-Buffon, Jaqueline
2018-06-11
The peroxidase (POD) enzyme, obtained from different sources, has been described in the literature regarding its good results of reduction in concentration or degradation levels of mycotoxins, such as aflatoxin B1, deoxynivalenol and zearalenone. This study aimed at evaluating the action of commercial peroxidase and peroxidase from soybean bran (SB) and rice bran (RB) in zearalenone (ZEA) reduction in a model solution and the characterization of the mechanism of enzyme action. POD was extracted from SB and RB in phosphate buffer by orbital agitation. Evaluation of the action of commercial POD and POD from SB and RB in ZEA reduction was carried out in phosphate buffer and aqueous solution, respectively. Parameters of K M and V max were determined in the concentration range from 0.16 to 6 µg mL -1 . ZEA reduction was determined and the mechanism of enzyme action was characterized by Fourier transform infrared spectroscopy and high-pressure liquid chromatography-electrospray tandem mass spectrometry. Commercial POD and POD from RB and SB reduced ZEA concentration by 69.9, 47.4 and 30.6% in 24 h, respectively. K M values were 39.61 and 8.90 µM whereas V max values were 0.170 and 0.011 µM min -1 for commercial POD and POD from RB, respectively. The characterization of the mechanism of enzyme action showed the oxidoreductive action of commercial POD in the mycotoxin. The use of commercial POD and POD from agro-industrial by-products, such as SB and RB, could be a promising alternative for ZEA biodegradation.
Srivastava, Rishi; Singh, Mohar; Bajaj, Deepak; Parida, Swarup K.
2016-01-01
Development and large-scale genotyping of user-friendly informative genome/gene-derived InDel markers in natural and mapping populations is vital for accelerating genomics-assisted breeding applications of chickpea with minimal resource expenses. The present investigation employed a high-throughput whole genome next-generation resequencing strategy in low and high pod number parental accessions and homozygous individuals constituting the bulks from each of two inter-specific mapping populations [(Pusa 1103 × ILWC 46) and (Pusa 256 × ILWC 46)] to develop non-erroneous InDel markers at a genome-wide scale. Comparing these high-quality genomic sequences, 82,360 InDel markers with reference to kabuli genome and 13,891 InDel markers exhibiting differentiation between low and high pod number parental accessions and bulks of aforementioned mapping populations were developed. These informative markers were structurally and functionally annotated in diverse coding and non-coding sequence components of genome/genes of kabuli chickpea. The functional significance of regulatory and coding (frameshift and large-effect mutations) InDel markers for establishing marker-trait linkages through association/genetic mapping was apparent. The markers detected a greater amplification (97%) and intra-specific polymorphic potential (58–87%) among a diverse panel of cultivated desi, kabuli, and wild accessions even by using a simpler cost-efficient agarose gel-based assay implicating their utility in large-scale genetic analysis especially in domesticated chickpea with narrow genetic base. Two high-density inter-specific genetic linkage maps generated using aforesaid mapping populations were integrated to construct a consensus 1479 InDel markers-anchored high-resolution (inter-marker distance: 0.66 cM) genetic map for efficient molecular mapping of major QTLs governing pod number and seed yield per plant in chickpea. Utilizing these high-density genetic maps as anchors, three major genomic regions harboring each of pod number and seed yield robust QTLs (15–28% phenotypic variation explained) were identified on chromosomes 2, 4, and 6. The integration of genetic and physical maps at these QTLs mapped on chromosomes scaled-down the long major QTL intervals into high-resolution short pod number and seed yield robust QTL physical intervals (0.89–2.94 Mb) which were essentially got validated in multiple genetic backgrounds of two chickpea mapping populations. The genome-wide InDel markers including natural allelic variants and genomic loci/genes delineated at major six especially in one colocalized novel congruent robust pod number and seed yield robust QTLs mapped on a high-density consensus genetic map were found most promising in chickpea. These functionally relevant molecular tags can drive marker-assisted genetic enhancement to develop high-yielding cultivars with increased seed/pod number and yield in chickpea. PMID:27695461
Code of Federal Regulations, 2011 CFR
2011-01-01
... pod attaching structures containing flammable fluid lines. 25.1182 Section 25.1182 Aeronautics and..., and engine pod attaching structures containing flammable fluid lines. (a) Each nacelle area immediately behind the firewall, and each portion of any engine pod attaching structure containing flammable...
Code of Federal Regulations, 2010 CFR
2010-01-01
... pod attaching structures containing flammable fluid lines. 25.1182 Section 25.1182 Aeronautics and..., and engine pod attaching structures containing flammable fluid lines. (a) Each nacelle area immediately behind the firewall, and each portion of any engine pod attaching structure containing flammable...
Computationally efficient simulation of unsteady aerodynamics using POD on the fly
NASA Astrophysics Data System (ADS)
Moreno-Ramos, Ruben; Vega, José M.; Varas, Fernando
2016-12-01
Modern industrial aircraft design requires a large amount of sufficiently accurate aerodynamic and aeroelastic simulations. Current computational fluid dynamics (CFD) solvers with aeroelastic capabilities, such as the NASA URANS unstructured solver FUN3D, require very large computational resources. Since a very large amount of simulation is necessary, the CFD cost is just unaffordable in an industrial production environment and must be significantly reduced. Thus, a more inexpensive, yet sufficiently precise solver is strongly needed. An opportunity to approach this goal could follow some recent results (Terragni and Vega 2014 SIAM J. Appl. Dyn. Syst. 13 330-65 Rapun et al 2015 Int. J. Numer. Meth. Eng. 104 844-68) on an adaptive reduced order model that combines ‘on the fly’ a standard numerical solver (to compute some representative snapshots), proper orthogonal decomposition (POD) (to extract modes from the snapshots), Galerkin projection (onto the set of POD modes), and several additional ingredients such as projecting the equations using a limited amount of points and fairly generic mode libraries. When applied to the complex Ginzburg-Landau equation, the method produces acceleration factors (comparing with standard numerical solvers) of the order of 20 and 300 in one and two space dimensions, respectively. Unfortunately, the extension of the method to unsteady, compressible flows around deformable geometries requires new approaches to deal with deformable meshes, high-Reynolds numbers, and compressibility. A first step in this direction is presented considering the unsteady compressible, two-dimensional flow around an oscillating airfoil using a CFD solver in a rigidly moving mesh. POD on the Fly gives results whose accuracy is comparable to that of the CFD solver used to compute the snapshots.
Epidemiologic research using probabilistic outcome definitions.
Cai, Bing; Hennessy, Sean; Lo Re, Vincent; Small, Dylan S
2015-01-01
Epidemiologic studies using electronic healthcare data often define the presence or absence of binary clinical outcomes by using algorithms with imperfect specificity, sensitivity, and positive predictive value. This results in misclassification and bias in study results. We describe and evaluate a new method called probabilistic outcome definition (POD) that uses logistic regression to estimate the probability of a clinical outcome using multiple potential algorithms and then uses multiple imputation to make valid inferences about the risk ratio or other epidemiologic parameters of interest. We conducted a simulation to evaluate the performance of the POD method with two variables that can predict the true outcome and compared the POD method with the conventional method. The simulation results showed that when the true risk ratio is equal to 1.0 (null), the conventional method based on a binary outcome provides unbiased estimates. However, when the risk ratio is not equal to 1.0, the traditional method, either using one predictive variable or both predictive variables to define the outcome, is biased when the positive predictive value is <100%, and the bias is very severe when the sensitivity or positive predictive value is poor (less than 0.75 in our simulation). In contrast, the POD method provides unbiased estimates of the risk ratio both when this measure of effect is equal to 1.0 and not equal to 1.0. Even when the sensitivity and positive predictive value are low, the POD method continues to provide unbiased estimates of the risk ratio. The POD method provides an improved way to define outcomes in database research. This method has a major advantage over the conventional method in that it provided unbiased estimates of risk ratios and it is easy to use. Copyright © 2014 John Wiley & Sons, Ltd.
Baykal, D.; Siskey, R.S.; Haider, H.; Saikko, V.; Ahlroos, T.; Kurtz, S.M.
2013-01-01
The introduction of numerous formulations of Ultra-high molecular weight polyethylene (UHMWPE), which is widely used as a bearing material in orthopedic implants, necessitated screening of bearing couples to identify promising iterations for expensive joint simulations. Pin-on-disk (POD) testers capable of multidirectional sliding can correctly rank formulations of UHMWPE with respect to their predictive in vivo wear behavior. However, there are still uncertainties regarding POD test parameters for facilitating clinically relevant wear mechanisms of UHMWPE. Studies on the development of POD testing were briefly summarized. We systematically reviewed wear rate data of UHMWPE generated by POD testers. To determine if POD testing was capable of correctly ranking bearings and if test parameters outlined in ASTM F732 enabled differentiation between wear behavior of various formulations, mean wear rates of non-irradiated, conventional (25–50 kGy) and highly crosslinked (≥90 kGy) UHMWPE were grouped and compared. The mean wear rates of non-irradiated, conventional and highly crosslinked UHMWPEs were 7.03, 5.39 and 0.67 mm3/MC. Based on studies that complied with the guidelines of ASTM F732, the mean wear rates of non-irradiated, conventional and highly crosslinked UHMWPEs were 0.32, 0.21 and 0.04 mm3/km, respectively. In both sets of results, the mean wear rate of highly crosslinked UHMPWE was smaller than both conventional and non-irradiated UHMWPEs (p<0.05). Thus, POD testers can compare highly crosslinked and conventional UHMWPEs despite different test parameters. Narrowing the allowable range for standardized test parameters could improve sensitivity of multi-axial testers in correctly ranking materials. PMID:23831149
Kilianski, Andy; O'Rourke, Amy T; Carlson, Crystal L; Parikh, Shannon M; Shipman-Amuwo, Frankie
2014-01-01
Increasing threats of bioterrorism and the emergence of novel disease agents, including the recent international outbreaks of H7N9 influenza and MERS-CoV, have stressed the importance and highlighted the need for public health preparedness at local, regional, and national levels. To test plans that were developed for mass prophylaxis scenarios, in April 2013 the Cook Country Department of Public Health (CCDPH) and the Triple Community (TripCom) Medical Reserve Corps (MRC) executed a full-scale mass prophylaxis exercise in response to a simulated anthrax bioterrorism attack. The exercise took place over 2 days and included the TripCom Point-of-Dispensing (POD) Management Team, volunteers from the TripCom MRC, and neighboring public health departments and MRCs. Individuals from the community volunteered as actors during the exercise, while local municipal, police, and fire personnel coordinated their responses to create the most realistic simulation possible. The exercise was designed to test the capacity of TripCom and CCDPH to implement plans for organizing municipal staff and volunteers to efficiently distribute prophylaxis to the community. Based on results from POD clinic flow, accuracy of prophylaxis distribution, and observations from evaluators, the exercise was successful in demonstrating areas that were operationally efficient as well as identifying areas that can be improved on. These include improvements to the just-in-time training for POD staff, the health screening and consent forms handed out to patients, the physical setup of the POD, and the command structure and communication for the management of POD operations. This article demonstrates the need for full-scale exercises and identifies gaps in POD planning that can be integrated into future plans, exercises, and emergency response.
POD and PPP with multi-frequency processing
NASA Astrophysics Data System (ADS)
Roldán, Pedro; Navarro, Pedro; Rodríguez, Daniel; Rodríguez, Irma
2017-04-01
Precise Orbit Determination (POD) and Precise Point Positioning (PPP) are methods for estimating the orbits and clocks of GNSS satellites and the precise positions and clocks of user receivers. These methods are traditionally based on processing the ionosphere-free combination. With this combination, the delay introduced in the signal when passing through the ionosphere is removed, taking advantage of the dependency of this delay with the square of the frequency. It is also possible to process the individual frequencies, but in this case it is needed to properly model the ionospheric delay. This modelling is usually very challenging, as the electron content in the ionosphere experiences important temporal and spatial variations. These two options define the two main kinds of processing: the dual-frequency ionosphere-free processing, typically used in the POD and in certain applications of PPP, and the single-frequency processing with estimation or modelisation of the ionosphere, mostly used in the PPP processing. In magicGNSS, a software tool developed by GMV for POD and PPP, a hybrid approach has been implemented. This approach combines observations from any number of individual frequencies and any number of ionosphere-free combinations of these frequencies. In such a way, the observations of ionosphere-free combination allow a better estimation of positions and orbits, while the inclusion of observations from individual frequencies allows to estimate the ionospheric delay and to reduce the noise of the solution. It is also possible to include other kind of combinations, such as geometry-free combination, instead of processing individual frequencies. The joint processing of all the frequencies for all the constellations requires both the estimation or modelisation of ionospheric delay and the estimation of inter-frequency biases. The ionospheric delay can be estimated from the single-frequency or dual-frequency geometry-free observations, but it is also possible to use a-priori information based on ionospheric models, on external estimations and on the expected behavior of the ionosphere. The inter-frequency biases appear because the delay of the signal inside the transmitter and the receiver strongly depends on its frequency. However, it is possible to include constraints in the estimator regarding these delays, assuming small variations over time. By using different types of combinations, all the available information from GNSS systems can be included in the processing. This is especially interesting for the case of Galileo satellites, which transmit in several frequencies, and the GPS IIF satellites, which transmit in L5 in addition to the traditional L1 and L2. Several experiments have been performed, to assess the improvement on performance of POD and PPP when using all the constellations and all the available frequencies for each constellation. This paper describes the new approach of multi-frequency processing, including the estimation of biases and ionospheric delays impacting on GNSS observations, and presents the results of the performed experimentation activities to assess the benefits in POD and PPP algorithms.
Lin, Shan-Zhi; Zhang, Zhi-Yi; Lin, Yuan-Zhen; Zhang, Qian; Guo, Huan
2004-02-01
To explore the role of calcium-calmodulin messenger system in the transduction of low temperature signal in woody plants, Populus tomentosa cuttings after being treated with CaCl(2) (10 mmol/L), Ca(2+) chelator EGTA (3 mmol/L), Ca(2+) channel inhibitor LaCl(3) (100 mmol/L) or CaM antagonist CPZ (50 mmol/L) were used for freezing acclimation at -3 degrees C. The changes in the calmodulin (CaM) and malonaldehyde (MDA) contents, the activities of superoxide dismutase (SOD), peroxidase (POD) and Ca(2+)-dependent adenosinetriphosphatase (Ca(2+)-ATPase) of mitochondrial membrane as well as freezing resistance (expressed as LT(50)) of cuttings were investigated to elucidate the physiological mechanisms by which trees adapt to freezing. The results showed that freezing acclimation increased the CaM content, the activities of SOD, POD and Ca(2+)-ATPase of mitochondrial membrane as well as freezing resistance of cuttings, and decreased the MDA content as compared with control cuttings. Treatment with CaCl(2) at the time of freezing acclimation enhanced the effect of freezing acclimation on the above-mentioned indexes, but this enhancement was abolished by Ca(2+)chelator EGTA, Ca(2+) channel inhibitor LaCl(3) or CaM antagonist CPZ, indicating that the calcium-calmodulin messenger system was involved in the course of freezing resistance development. The presence of CaCl(2) at the same time of freezing acclimation also reduced the degree of decline in CaM content, and in SOD, POD and Ca(2+)-ATPase activities caused by freezing stress at -14 degrees C, and enhanced the level of increase in CaM content, and in SOD, POD and Ca(2+)-ATPase activity in the recovery periods at 25 degrees C . The change in CaM content was found to be closely correlated to the levels of SOD, POD and Ca(2+)-ATPase, and to the degree of freezing resistance of cuttings during freezing acclimation either with or without CaCl(2) treatment. It was suggested that the increase of CaM content induced by CaCl(2) treatment promote the formation of Ca(2+)-CaM complexes, which effectively activates the activities of SOD, POD and mitochondrial Ca(2+)-ATPase and then further result in the adaptive changes associated with the development and enhancement of freezing resistance. Thus, It could be concluded that Ca(2+)-calmodulin may be involved in the regulation of the increase in SOD, POD and Ca(2+)-ATPase activities, and the induction of freezing resistance of cuttings.
Cao, De-ju; Shi, Xiao-dong; Li, Hao; Xie, Pan-pan; Zhang, Hui-min; Deng, Juan-wei; Liang, Yue-gan
2015-02-01
Effects of various concentrations (0.5, 1.0, 2.5, 5.0, 7.5, and 10.0 mg/L) of lead (Pb(2+)) on the growth, bioaccumulation, and antioxidative defense system of green algae, Cladophora, was investigated. Low concentrations of Pb(2+) accelerated Cladophora growth, but concentrations of 10.0 mg/L and above inhibited the growth because of the hinderance to photosynthesis. The total soluble sugar content of Cladophora was affected by Pb(2+) treatment, but the protein content showed no significant changes. The malondialdehyde (MDA) content and peroxidase(POD) activity of Cladophora gradually increased whereas superoxide dismutase(SOD) decreased with Pb(2+) concentrations. Catalase (CAT) activity exhibited no significant changes following Pb(2+) treatment. Pb(2+) accumulated in Cladophora and that the lead content in Cladophora was correlated with POD growth, MDA, and Metallothionein (MT). POD and MT play a role in the survival of Cladophora in Pb-contaminated environments. This study suggests that Cladophora can be a choice organism for the phytoremediation of Pb-polluted coastal areas. Copyright © 2014 Elsevier Inc. All rights reserved.
Particle protection capability of SEMI-compliant EUV-pod carriers
NASA Astrophysics Data System (ADS)
Huang, George; He, Long; Lystad, John; Kielbaso, Tom; Montgomery, Cecilia; Goodwin, Frank
2010-04-01
With the projected rollout of pre-production extreme ultraviolet lithography (EUVL) scanners in 2010, EUVL pilot line production will become a reality in wafer fabrication companies. Among EUVL infrastructure items that must be ready, EUV mask carriers remain critical. To keep non-pellicle EUV masks free from particle contamination, an EUV pod concept has been extensively studied. Early prototypes demonstrated nearly particle-free results at a 53 nm PSL equivalent inspection sensitivity during EUVL mask robotic handling, shipment, vacuum pump-purge, and storage. After the passage of SEMI E152, which specifies the EUV pod mechanical interfaces, standards-compliant EUV pod prototypes, including a production version inner pod and prototype outer pod, were built and tested. Their particle protection capability results are reported in this paper. A state-of-the-art blank defect inspection tool was used to quantify their defect protection capability during mask robotic handling, shipment, and storage tests. To ensure the availability of an EUV pod for 2010 pilot production, the progress and preliminary test results of pre-production EUV outer pods are reported as well.
Kim, Yun-Hee; Yang, Kyoung-Sil; Kim, Cha Young; Ryu, Sun-Hwa; Song, Wan-Keun; Kwon, Suk-Yoon; Lee, Haeng-Soon; Bang, Jae-Wook; Kwak, Sang-Soo
2008-03-31
Three peroxidase (POD) cDNAs were isolated from dehydration-treated fibrous roots of sweetpotato (Ipomoea batatas) plant via the screening of a cDNA library, and their expressions were assessed to characterize functions of each POD in relation to environmental stress. Three PODs were divided into two groups, designated the basic PODs (swpb4, swpb5) and the anionic PODs (swpa7), on the basis of the pI values of mature proteins. Fluorescence microscope analysis indicated that three PODs are secreted into the extracellular space. RTPCR analysis revealed that POD genes have diverse expression patterns in a variety of plant tissues. Swpb4 was abundantly expressed in stem tissues, whereas the expression levels of swpb5 and swpa7 transcripts were high in fibrous and thick pigmented roots. Swpb4 and swpa7 showed abundant expression levels in suspension cultured cells. Three POD genes responded differently in the leaf and fibrous roots in response to a variety of stresses including dehydration, temperature stress, stress-associated chemicals, and pathogenic bacteria.
A model "go-kit" for use at Strategic National Stockpile Points of Dispensing.
May, Larissa; Cote, Timothy; Hardeman, Bernard; Gonzalez, Gabriela R; Adams, Sherry B; Blair, Roderick K; Pane, Gregg
2007-01-01
The Strategic National Stockpile (SNS) is a national repository of pharmaceuticals and other medical supplies forseeably needed during a medical disaster. In the event of SNS deployment, state and local public health authorities must be prepared to receive, distribute, and dispense the materials. We propose a cache of supplies, termed the "POD go-kit," prepared in advance and locally available prior to the establishment of Points of Dispensing (POD) for SNS material. Characteristics of the preassembled go-kit are its multiplicity of use, ease of storage and transportation, minimal redundancy with SNS material, and packaging in a manner consistent with POD function. The POD go-kit is assembled into 4 separate "subkits": administrative supplies, patient routing supplies, dispensing supplies, and POD staff protection supplies. Incorporating existing practices from the SNS Listserv, this article itemizes the contents of the POD go-kit and its subkits and provides a rationale for its packaging. The Division of Strategic National Stockpile (DSNS) has not certified the proposed "POD go-kit" as a standardized POD go-kit.
A comparison of Probability Of Detection (POD) data determined using different statistical methods
NASA Astrophysics Data System (ADS)
Fahr, A.; Forsyth, D.; Bullock, M.
1993-12-01
Different statistical methods have been suggested for determining probability of detection (POD) data for nondestructive inspection (NDI) techniques. A comparative assessment of various methods of determining POD was conducted using results of three NDI methods obtained by inspecting actual aircraft engine compressor disks which contained service induced cracks. The study found that the POD and 95 percent confidence curves as a function of crack size as well as the 90/95 percent crack length vary depending on the statistical method used and the type of data. The distribution function as well as the parameter estimation procedure used for determining POD and the confidence bound must be included when referencing information such as the 90/95 percent crack length. The POD curves and confidence bounds determined using the range interval method are very dependent on information that is not from the inspection data. The maximum likelihood estimators (MLE) method does not require such information and the POD results are more reasonable. The log-logistic function appears to model POD of hit/miss data relatively well and is easy to implement. The log-normal distribution using MLE provides more realistic POD results and is the preferred method. Although it is more complicated and slower to calculate, it can be implemented on a common spreadsheet program.
Effect of climate variables on cocoa black pod incidence in Sabah using ARIMAX model
NASA Astrophysics Data System (ADS)
Ling Sheng Chang, Albert; Ramba, Haya; Mohd. Jaaffar, Ahmad Kamil; Kim Phin, Chong; Chong Mun, Ho
2016-06-01
Cocoa black pod disease is one of the major diseases affecting the cocoa production in Malaysia and also around the world. Studies have shown that the climate variables have influenced the cocoa black pod disease incidence and it is important to quantify the black pod disease variation due to the effect of climate variables. Application of time series analysis especially auto-regressive moving average (ARIMA) model has been widely used in economics study and can be used to quantify the effect of climate variables on black pod incidence to forecast the right time to control the incidence. However, ARIMA model does not capture some turning points in cocoa black pod incidence. In order to improve forecasting performance, other explanatory variables such as climate variables should be included into ARIMA model as ARIMAX model. Therefore, this paper is to study the effect of climate variables on the cocoa black pod disease incidence using ARIMAX model. The findings of the study showed ARIMAX model using MA(1) and relative humidity at lag 7 days, RHt - 7 gave better R square value compared to ARIMA model using MA(1) which could be used to forecast the black pod incidence to assist the farmers determine timely application of fungicide spraying and culture practices to control the black pod incidence.
The scaffolding and signaling functions of a localization factor impact polar development
Curtis, Patrick D.; Quardokus, Ellen M.; Lawler, Melanie L.; Guo, Xiaoyun; Klein, David; Chen, Joseph C.; Arnold, Randy J.; Brun, Yves V.
2012-01-01
SUMMARY In the differentiating alphaproteobacterium Caulobacter crescentus, organelle synthesis at cell poles is critical to forming different progeny after cell division. Coordination of polar organelle synthesis, including pili and holdfast, and flagellum ejection, is mediated in part by the scaffolding protein PodJ. At the time of cell division, PodJ undergoes regulated processing to a short form that persists at the flagellar pole of swarmer cells. This study analyzes how PodJ’s role in structural and signaling protein localization impacts organelle synthesis. A PodJ mutant with an internal deletion exhibits reduced sensitivity to pili-tropic phage ΦCbK, resulting from reduced pilA gene expression, which can be linked to altered signaling protein localization. The phage sensitivity defect of a ΔpodJ mutant can be partially suppressed by ectopic pilA expression. Induction of PodJ processing, by manipulation of podJ itself or controlled perP expression, resulted in decreased pilus biogenesis and, when coupled with a podJ mutation that reduced pilA expression, led to complete loss of phage sensitivity. As a whole, the results show that PodJ’s scaffolding role for structural and signaling proteins both contribute to flagellar pole organelle development. PMID:22512778
An adaptive model order reduction by proper snapshot selection for nonlinear dynamical problems
NASA Astrophysics Data System (ADS)
Nigro, P. S. B.; Anndif, M.; Teixeira, Y.; Pimenta, P. M.; Wriggers, P.
2016-04-01
Model Order Reduction (MOR) methods are employed in many fields of Engineering in order to reduce the processing time of complex computational simulations. A usual approach to achieve this is the application of Galerkin projection to generate representative subspaces (reduced spaces). However, when strong nonlinearities in a dynamical system are present and this technique is employed several times along the simulation, it can be very inefficient. This work proposes a new adaptive strategy, which ensures low computational cost and small error to deal with this problem. This work also presents a new method to select snapshots named Proper Snapshot Selection (PSS). The objective of the PSS is to obtain a good balance between accuracy and computational cost by improving the adaptive strategy through a better snapshot selection in real time (online analysis). With this method, it is possible a substantial reduction of the subspace, keeping the quality of the model without the use of the Proper Orthogonal Decomposition (POD).
The effects of Psychotropic drugs On Developing brain (ePOD) study: methods and design.
Bottelier, Marco A; Schouw, Marieke L J; Klomp, Anne; Tamminga, Hyke G H; Schrantee, Anouk G M; Bouziane, Cheima; de Ruiter, Michiel B; Boer, Frits; Ruhé, Henricus G; Denys, Damiaan; Rijsman, Roselyne; Lindauer, Ramon J L; Reitsma, Hans B; Geurts, Hilde M; Reneman, Liesbeth
2014-02-19
Animal studies have shown that methylphenidate (MPH) and fluoxetine (FLX) have different effects on dopaminergic and serotonergic system in the developing brain compared to the developed brain. The effects of Psychotropic drugs On the Developing brain (ePOD) study is a combination of different approaches to determine whether there are related findings in humans. Animal studies were carried out to investigate age-related effects of psychotropic drugs and to validate new neuroimaging techniques. In addition, we set up two double-blind placebo controlled clinical trials with MPH in 50 boys (10-12 years) and 50 young men (23-40 years) suffering from ADHD (ePOD-MPH) and with FLX in 40 girls (12-14 years) and 40 young women (23-40 years) suffering from depression and anxiety disorders (ePOD-SSRI). Trial registration numbers are: Nederlands Trial Register NTR3103 and NTR2111. A cross-sectional cohort study on age-related effects of these psychotropic medications in patients who have been treated previously with MPH or FLX (ePOD-Pharmo) is also ongoing. The effects of psychotropic drugs on the developing brain are studied using neuroimaging techniques together with neuropsychological and psychiatric assessments of cognition, behavior and emotion. All assessments take place before, during (only in case of MPH) and after chronic treatment. The combined results of these approaches will provide new insight into the modulating effect of MPH and FLX on brain development.
The effects of Psychotropic drugs On Developing brain (ePOD) study: methods and design
2014-01-01
Background Animal studies have shown that methylphenidate (MPH) and fluoxetine (FLX) have different effects on dopaminergic and serotonergic system in the developing brain compared to the developed brain. The effects of Psychotropic drugs On the Developing brain (ePOD) study is a combination of different approaches to determine whether there are related findings in humans. Methods/Design Animal studies were carried out to investigate age-related effects of psychotropic drugs and to validate new neuroimaging techniques. In addition, we set up two double-blind placebo controlled clinical trials with MPH in 50 boys (10–12 years) and 50 young men (23–40 years) suffering from ADHD (ePOD-MPH) and with FLX in 40 girls (12–14 years) and 40 young women (23–40 years) suffering from depression and anxiety disorders (ePOD-SSRI). Trial registration numbers are: Nederlands Trial Register NTR3103 and NTR2111. A cross-sectional cohort study on age-related effects of these psychotropic medications in patients who have been treated previously with MPH or FLX (ePOD-Pharmo) is also ongoing. The effects of psychotropic drugs on the developing brain are studied using neuroimaging techniques together with neuropsychological and psychiatric assessments of cognition, behavior and emotion. All assessments take place before, during (only in case of MPH) and after chronic treatment. Discussion The combined results of these approaches will provide new insight into the modulating effect of MPH and FLX on brain development. PMID:24552282
da Silva, Camila Sousa; de Souza, Evaristo Jorge Oliveira; Pereira, Gerfesson Felipe Cavalcanti; Cavalcante, Edwilka Oliveira; de Lima, Ewerton Ivo Martins; Torres, Thaysa Rodrigues; da Silva, José Ricardo Coelho; da Silva, Daniel Cézar
2017-02-01
The objective was to evaluate the intake, digestibility, and ingestive sheep behavior with feeding phytogenic additives derived from plant extracts. Five non-emasculated sheep without defined breed at 28 ± 1.81 kg initial body weight and 6 months age were used. Treatments consisted of administering four phytogenic additives from the garlic extracts, coriander seed, oregano, and pods of mesquite, plus a control treatment (without additive). The ration was composed of Tifton 85 hay grass, corn, soybean meal, and mineral salt. As experimental design, we used a 5 × 5 Latin square design (five treatments and five periods). The data were analyzed through the mixed model through the procedure PROC MIXED of software Systems Statistical Analysis version 9.1, with comparation analysis between the treatment without additive (control) with phytogenic additives produced from vegetable extracts of mesquite pod, of coriander seed, the bulb of garlic, and the oregano leaves. There were no significant differences for the nutrient intake and ingestive behavior patterns. However, the additive intake derived from mesquite pods and coriander extracts provided an increase in digestibility. Extracts from garlic, coriander, and mesquite pods can be used as phytogenic additives in feeding sheep.
Survey of college students on iPod use and hearing health.
Danhauer, Jeffrey L; Johnson, Carole E; Byrd, Anne; DeGood, Laura; Meuel, Caitlin; Pecile, Angela; Koch, Lindsey L
2009-01-01
The popularity of personal listening devices (PLDs) including iPods has increased dramatically over the past decade. PLDs allow users to listen to music uninterrupted for prolonged periods and at levels that may pose a risk for hearing loss in some listeners, particularly those using earbud earphones that fail to attenuate high ambient noise levels and necessitate increasing volume for acoustic enjoyment. Earlier studies have documented PLD use by teenagers and adults, but omitted college students, which represent a large segment of individuals who use these devices. This study surveyed college students' knowledge about, experiences with, attitudes toward, and practices and preferences for hearing health and use of iPods and/or other PLDs. The study was designed to help determine the need, content, and preferred format for educational outreach campaigns regarding safe iPod use to college students. An 83-item questionnaire was designed and used to survey college students' knowledge about, experiences with, attitudes toward, and practices/preferences for hearing health and PLD use. The questionnaire assessed Demographics and Knowledge of Hearing Health, iPod Users' Practices and Preferences, Attitudes toward iPod Use, and Reasons for iPod Use. Generally, most college students were knowledgeable about hearing health but could use information about signs of and how to prevent hearing loss. Two-thirds of these students used iPods, but not at levels or for durations that should pose excessive risks for hearing loss when listening in quiet environments. However, most iPod users could be at risk for hearing loss given a combination of common practices. Most of these college students should not be at great risk of hearing loss from their iPods when used conscientiously. Some concern is warranted for a small segment of these students who seemed to be most at risk because they listened to their iPods at high volume levels for long durations using earbuds, and reported that they may already have hearing loss due to their iPods.
Xia, Hong; Luo, Zhendong
2017-01-01
In this study, we devote ourselves to establishing a stabilized mixed finite element (MFE) reduced-order extrapolation (SMFEROE) model holding seldom unknowns for the two-dimensional (2D) unsteady conduction-convection problem via the proper orthogonal decomposition (POD) technique, analyzing the existence and uniqueness and the stability as well as the convergence of the SMFEROE solutions and validating the correctness and dependability of the SMFEROE model by means of numerical simulations.
Development of a UAV-based Global Ozone Lidar Demonstrator (GOLD)
NASA Astrophysics Data System (ADS)
Browell, E. V.; Deyoung, R. J.; Hair, J. W.; Ismail, S.; McGee, T.; Hardesty, R. M.; Brewer, W. A.; McDermid, I. S.
2006-12-01
Global ozone measurements are needed across the troposphere with high vertical resolution to enable comprehensive studies of continental and intercontinental atmospheric chemistry and dynamics, which are affected by diverse natural and human-induced processes. The development of a unattended aerial vehicle (UAV) based Global Ozone Lidar Demonstrator (GOLD) is an important step in enabling a space-based ozone and aerosol lidar and for conducting unique UAV-based large-scale atmospheric investigations. The GOLD system will incorporate the most advanced technology developed under the NASA Laser Risk Reduction Program (LRRP) and the Small Business Innovative Research (SBIR) program to produce a compact, autonomously operating ozone and aerosol Differential Absorption Lidar (DIAL) system for a UAV platform. This system will leverage advanced Nd:YAG and optical parametric oscillator (OPO) laser technologies being developed by ITT Industries under the LRRP and the autonomously operating ozone DIAL system being developed by Science and Engineering Services Inc. (SESI) under an SBIR Phase-3 contract. Laser components from ITT will be integrated into the SESI DIAL system, and the resulting GOLD system will be flight tested on a NASA UAV. The development of the GOLD system was initiated as part of the NASA Instrument Incubator Program in December 2005, and great progress has been made towards completing major GOLD subsystems. ITT has begun construction of the high-power Nd:YAG pump laser and the ultraviolet OPO for generating the ozone DIAL wavelengths of 290 and 300 nm and the aerosol visible wavelength at 532 nm. SESI is completing the Phase-3 SBIR contract for the delivery and demonstration of the ozone DIAL receiver and data system, and NOAA is completing detector evaluations for use in the GOLD system. Welch Mechanical is examining system designs for integrating GOLD into the external pod that will be hung under the new IKANA (Predator-B) UAV that NASA Dryden is acquiring. Details of the GOLD system design and development will be presented in this paper, and science applications for a UAV-based and space-based ozone lidar will be discussed.
Zhang, Zhongqiang; Yang, Xiu; Lin, Guang
2016-04-14
Sensor placement at the extrema of Proper Orthogonal Decomposition (POD) is efficient and leads to accurate reconstruction of the wind field from a limited number of measure- ments. In this paper we extend this approach of sensor placement and take into account measurement errors and detect possible malfunctioning sensors. We use the 48 hourly spa- tial wind field simulation data sets simulated using the Weather Research an Forecasting (WRF) model applied to the Maine Bay to evaluate the performances of our methods. Specifically, we use an exclusion disk strategy to distribute sensors when the extrema of POD modes are close.more » It turns out that this strategy can also reduce the error of recon- struction from noise measurements. Also, by a cross-validation technique, we successfully locate the malfunctioning sensors.« less
Gu, Fenglin; Chen, Yonggan; Hong, Yinghua; Fang, Yiming; Tan, Lehe
2017-12-01
High-performance liquid chromatography-mass spectrometry (LC-MS) was used for comprehensive metabolomic fingerprinting of vanilla fruits prepared from the curing process. In this study, the metabolic changes of vanilla pods and vanilla beans were characterized using MS-based metabolomics to elucidate the biosynthesis of vanillin. The vanilla pods were significantly different from vanilla beans. Seven pathways of vanillin biosynthesis were constructed, namely, glucovanillin, glucose, cresol, capsaicin, vanillyl alcohol, tyrosine, and phenylalanine pathways. Investigations demonstrated that glucose, cresol, capsaicin, and vanillyl alcohol pathway were detected in a wide range of distribution in microbial metabolism. Thus, microorganisms might have participated in vanillin biosynthesis during vanilla curing. Furthermore, the ion strength of glucovanillin was stable, which indicated that glucovanillin only participated in the vanillin biosynthesis during the curing of vanilla.
UAVSAR Instrument: Current Operations and Planned Upgrades
NASA Technical Reports Server (NTRS)
Lou, Yunling; Hensley, Scott; Chao, Roger; Chapin, Elaine; Heavy, Brandon; Jones, Cathleen; Miller, Timothy; Naftel, Chris; Fratello, David
2011-01-01
The Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) instrument is a pod-based Lband polarimetric synthetic aperture radar (SAR), specifically designed to acquire airborne repeat track SAR data for differential interferometric measurements. This instrument is currently installed on the NASA Gulfstream- III (G-III) aircraft with precision real-time Global Positioning System (GPS) and a sensor-controlled flight management system for precision repeat-pass data acquisitions. UAVSAR has conducted engineering and preliminary science data flights since October 2007 on the G-III. We are porting the radar to the Global Hawk Unmanned Airborne Vehicle (UAV) to enable long duration/long range data campaigns. We plan to install two radar pods (each with its own active array antenna) under the wings of the Global Hawk to enable the generation of precision topographic maps and single pass polarimetric-interferometry (SPI) providing vertical structure of ice and vegetation. Global Hawk's range of 8000 nm will enable regional surveys with far fewer sorties as well as measurements of remote locations without the need for long and complicated deployments. We are also developing P-band polarimetry and Ka-band single-pass interferometry capabilities on UAVSAR by replacing the radar antenna and front-end electronics to operate at these
A Predeployment Limited Technical Assessment of the iPod Touch to Aid the United States Marine Corps
2009-08-01
public release; distribution is unlimited. 13. SUPPLEMENTARY NOTES "Safari," " iTunes ," "iPod," "iPod touch," and "iPhone" are registered trademarks...Marine Corps unit and assessed during the EUE.1 1 “Safari,” “ iTunes ,” “iPod,” “iPod touch,” and “iPhone...application store, YouTube, the Apple Safari Web browser, maps, weather, and Apple iTunes . Participants then arranged a paper prototype home screen
On The Lookout: The Air Mobile Ground Security and Surveillance System (AMGSS) Has Arrived
1995-01-01
dimensional mobility allowed by the VTOL platform are ideally suited to this concept. If (during landing) there is loss of communications detected on the...vertical-take-off-and-landing, unmanned aircraft) with a sensor pod mounted on top as shown in figure 3. Projected weight of the mission-ready AMP...to restart the engine twice. Weight and power estimates are based on commercially available hardware, modified in some cases for the AMGSSS
2007-06-13
KENNEDY SPACE CENTER, FLA. -- Another view of the area of orbiter Endeavour's orbital maneuvering system, or OMS, pod where the tear occurred on Atlantis during launch of mission STS-117 on June 8, 2007. Repair is under consideration following testing at KSC and Houston. The test articles each feature three tiles (Low Temperature Reusable Surface Insulation, or LRSI) affixed next to two FIB blankets, simulating the thermal protection system set-up on Atlantis' OMS pod in the vicinity of the in-flight anomaly. These test articles were flown to Texas the morning of June 14. The TPS team at KSC has also provided a total of 22 FIB samples for other testing and analysis. Photo credit: NASA/Kim Shiflett
2007-06-13
KENNEDY SPACE CENTER, FLA. -- Another view of the area of orbiter Endeavour's orbital maneuvering system, or OMS, pod where the tear occurred on Atlantis during launch of mission STS-117 on June 8, 2007. Repair is under consideration following testing at KSC and Houston. The test articles each feature three tiles (Low Temperature Reusable Surface Insulation, or LRSI) affixed next to two FIB blankets, simulating the thermal protection system set-up on Atlantis' OMS pod in the vicinity of the in-flight anomaly. These test articles were flown to Texas the morning of June 14. The TPS team at KSC has also provided a total of 22 FIB samples for other testing and analysis. Photo credit: NASA/Kim Shiflett
Prospective randomized trial compares suction versus water seal for air leaks.
Cerfolio, R J; Bass, C; Katholi, C R
2001-05-01
Surgeons treat air leaks differently. Our goal was to evaluate whether it is better to place chest tubes on suction or water seal for stopping air leaks after pulmonary surgery. A second goal was to evaluate a new classification system for air leaks that we developed. Patients were prospectively randomized before surgery to receive suction or water seal to their chest tubes on postoperative day (POD) #2. Air leaks were described and quantified daily by a classification system and a leak meter. The air-leak meter scored leaks from 1 (least) to 7 (greatest). The group randomized to water seal stayed on water seal unless a pneumothorax developed. On POD #2, 33 of 140 patients had an air leak. Eighteen patients had been preoperatively randomized to water seal and 15 to suction. Air leaks resolved in 12 (67%) of the water seal patients by the morning of POD #3. All 6 patients whose air leak did not stop had a leak that was 4/7 or greater (p < 0.0001) on the leak meter. Of the 15 patients randomized to suction, only 1 patient's air leak (7%) resolved by the morning of POD #3. The randomization aspect of the trial was ended and statistical analysis showed water seal was superior (p = 0.001). The remaining 14 patients were then placed to water seal and by the morning of POD #4, 13 patients' leaks had stopped. Of the 32 total patients placed to seal, 7 (22%) developed a pneumothorax and 6 of these 7 patients had leaks that were 4/7 or greater (p = 0.001). Placing chest tubes on water seal seems superior to wall suction for stopping air leaks after pulmonary resection. However, water seal does not stop expiratory leaks that are 4/7 or greater. Pneumothorax may occur when chest tubes are placed on seal with leaks this large.
Sharma, Upendra K; Sharma, Nandini; Sinha, Arun K; Kumar, Neeraj; Gupta, Ajai P
2009-10-01
In this study, two novel chromatographic methods based on monolithic column high-performance liquid chromatography (HPLC) and ultra-performance liquid chromatography (UPLC) were developed for the ultrafast determination of principal flavor compounds namely vanillin, vanillic acid, p-hydroxybenzoic acid, and p-hydroxybenzaldehyde in ethanolic extracts of Vanilla planifolia pods. Good separation was achieved within 2.5 min using Chromolith RP18e column (100 mm x 4.6 mm) for HPLC and Acquity BEH C-18 (100 mm x 2.1 mm, 1.7 microm) column for UPLC. Both methods were compared in terms of total analysis time, mobile phase consumption, sensitivity, and validation parameters like precision, accuracy, LOD, and LOQ. Further, system suitability test data including resolution, capacity factor, theoretical plates, and tailing factor was determined for both the methods by ten replicate injections. Monolithic column based HPLC gave better results for most of the selected parameters while UPLC was found to be more eco-friendly with low mobile phase consumption and better sensitivity. Both methods may be used conveniently for the high throughput analysis of large number of samples in comparison to traditional particulate column.
NASA Astrophysics Data System (ADS)
Lubis, M.; Gana, A.; Maysarah, S.; Ginting, M. H. S.; Harahap, M. B.
2018-02-01
The production of bioplastic from jackfruit seed starch reinforced with microcrystalline cellulose (MCC) cocoa pod husk using glycerol as plasticizer was investigated to determine the most optimum mass and volume of MCC and glycerol in producing bioplastics. To produce MCC, Cocoa pod husk was subjected to alkali treatment, bleaching, and hydrochloric acid hydrolysis. The degree of crystallinity of MCC, were determined by XRD, functional group by FT-IR and morphologycal analysis by SEM. Analysis of bioplastic mechanical properties includes tensile strength and elongation at break based on ASTM D882 standard. Bioplastics were produced by casting method from jackfruit seed starch and reinforced with MCC from cocoa pod husk at starch mass to MCC ratio of 6:4, 7:3, 8:2, and 9:1, using glycerol as plasticizer at 20%, 25%, 30% (wt/v of glycerol to starch). From the result, the isolated MCC from cocoa pod husk were in a form of rod-like shape of length 5-10 µm with diameter 11.635 nm and 74% crystallinity. The highest tensile strength of bioplastics was obtained at starch to MCC mass ratio of 8:2, addition of 20% glycerol with measured tensile strength of 0.637 MPa and elongation at break of 7.04%. Transform infrared spectroscopy showed the functional groups of bioplastics, which the majority of O-H groups were found at the bioplastics with reinforcing filler MCC that represented substantial hydrogen bonds.
Kosse, Nienke M; Caljouw, Simone; Vervoort, Danique; Vuillerme, Nicolas; Lamoth, Claudine J C
2015-08-01
Accelerometer-based assessments can identify elderly with an increased fall risk and monitor interventions. Smart devices, like the iPod Touch, with built-in accelerometers are promising for clinical gait and posture assessments due to easy use and cost-effectiveness. The aim of the present study was to establish the validity and reliability of the iPod Touch for gait and posture assessment. Sixty healthy participants (aged 18-75 years) were measured with an iPod Touch and stand-alone accelerometer while they walked under single- and dual-task conditions, and while standing in parallel and semi-tandem stance with eyes open, eyes closed and when performing a dual task. Cross-correlation values (CCV) showed high correspondence of anterior-posterior and medio-lateral signal patterns (CCV's ≥ 0.88). Validity of gait parameters (foot contacts, index of harmonicity, and amplitude variability) and standing posture parameters [root mean square of accelerations, median power frequency (MPF) and sway area] as indicated by intra-class correlation (ICC) was high (ICC = 0.85-0.99) and test-retest reliability was good (ICC = 0.81-0.97), except for MPF (ICC = 0.59-0.87). Overall, the iPod Touch obtained valid and reliable measures of gait and postural control in healthy adults of all ages under different conditions. Additionally, smart devices have the potential to be used for clinical gait and posture assessments.
Tani, Masaji; Kawai, Manabu; Okada, Ken-Ichi; Hirono, Seiko; Hotta, Tsukasa; Takifuji, Katsunari; Yamaue, Hiroki
2015-05-01
Laparoscopic cholecystectomy (LC) has become the standard procedure, and contributes to a shorter hospital stay. However, there have been no reports regarding when the patients can be discharged in terms of their health-related quality of life (HRQOL). The HRQOL was evaluated by using the SF-8 health survey (SF-8) 24-hour version in 127 consecutive patients treated from May 2007 to December 2008. The HRQOL and a visual analogue scale (VAS) score were assessed on the day before surgery and on postoperative day (POD) 1, POD2 and POD7. All scores of the eight domains on POD1 were significantly decreased compared to the preoperative score (P < 0.05), and seven scores were still decreased on POD2, with the mental health (MH) domain showing an improvement. On POD7, the general health score improved to the preoperative level. The physical component summary 8 (PCS-8) was suppressed for all 7 days after LC. The mental health component summary 8 (MCS-8) was improved to the preoperative level on POD2, despite the significant suppression observed on POD1 (P < 0.05). The VAS score was higher in the low PCS-8 (PCS-8 < 42.4) and low MCS-8 (MCS-8 < 40.6) patients than in the high PCS-8 and high MCS-8 patients. The HRQOL score demonstrated the improvement of the MCS-8 on POD2, which might suggest that a discharge of LC patients is appropriate on POD2 in terms of the patients' point of view.
Mateos-Aparicio, Inmaculada; Redondo-Cuenca, Araceli; Villanueva-Suárez, María-José
2012-02-01
By-products generated during the processing of plant food can be considered a promising source of dietary fibre as a functional compound. The dietary fibre composition, soluble sugars and antioxidant activity of the extractable polyphenols of pea and broad bean by-products have been analysed in this study. Total dietary fibre using AOAC methods plus hydrolysis (broad bean pod: 337.3 g kg⁻¹; pea pod: 472.6 g kg⁻¹) is higher (P < 0.05) in both by-products than with the Englyst method (broad bean pod: 309.7 g kg⁻¹; pea pod: 434.6 g kg⁻¹). The main monomers are uronic acids, glucose, arabinose and galactose in broad bean pods. However, pea pods are very rich in glucose and xylose. The soluble sugars analysed by high-performance liquid chromatography in both by-products have glucose as the most important component, followed by sucrose and fructose. The ferric reducing antioxidant power (broad bean pod: 406.4 µmol Trolox equivalents g⁻¹; pea pod: 25.9 µmol Trolox equivalents g⁻¹) and scavenging effect on 2,2-diphenyl-1-picrylhydrazyl radical (EC₅₀ of broad bean pod: 0.4 mg mL⁻¹; EC₅₀ of pea pod: 16.0 mg mL⁻¹) were also measured. Broad bean and pea by-products are very rich in dietary fibre, particularly insoluble dietary fibre and their extractable polyphenols demonstrate antioxidant activity. Therefore they might be regarded as functional ingredients. Copyright © 2011 Society of Chemical Industry.
Wan, Liyun; Li, Bei; Lei, Yong; Yan, Liying; Ren, Xiaoping; Chen, Yuning; Dai, Xiaofeng; Jiang, Huifang; Zhang, Juncheng; Guo, Wei; Chen, Ao; Liao, Boshou
2017-01-01
Pod size is the major yield component and a key target trait that is selected for in peanut breeding. However, although numerous quantitative trait loci (QTLs) for peanut pod size have been described, the molecular mechanisms underlying the development of this characteristic remain elusive. A peanut mutant with a narrower pod was developed in this study using ethyl methanesulfonate (EMS) mutagenesis and designated as the “pod width” mutant line (pw). The fresh pod weight of pw was only about 40% of that seen in the wild-type (WT) Zhonghua16, while the hull and seed filling of the mutant both also developed at earlier stages. Pods from both pw and WT lines were sampled 20, 40, and 60 days after flowering (DAF) and used for RNA-Seq analysis; the results revealed highly differentially expressed lignin metabolic pathway genes at all three stages, but especially at DAF 20 and DAF 40. At the same time, expression of genes related to auxin signal transduction was found to be significantly repressed during the pw early pod developmental stage. A genome-wide comparative analysis of expression profiles revealed 260 differentially expressed genes (DEGs) across all three stages, and two candidate genes, c26901_g1 (CAD) and c37339_g1 (ACS), responsible for pod width were identified by integrating expression patterns and function annotation of the common DEGs within the three stages. Taken together, the information provided in this study illuminates the processes underlying peanut pod development, and will facilitate further identification of causal genes and the development of improved peanut varieties with higher yields. PMID:29170673
Seed abortion in wind-dispersed pods of Dalbergia sissoo: maternal regulation or sibling rivalry?
Ganeshaiah, K N; Shaanker, R Uma
1988-10-01
Dalbergia sissoo, a wind-dispersed tropical tree, shows a positively skewed distribution of seeds per pod. This is attributed to the enhanced dispersal advantage of few-seeded pods due to their reduced wing loading (ratio of weight to pod surface area) and low settling velocity. The proximate mechanisms causing the positively skewed distribution were investigated. The distribution could not be attributed to the distribution pattern of ovule number per ovary, pollen grain limitation, lack of ovule fertilization, or post-fertilization elimination of many-seeded pods. Rather, it was caused by the post-fertilization abortion of seeds within a pod 2 weeks after fertilization. This intra-pod seed abortion (IPSA) is due to a dominance hierarchy of fertilized ovules from the distal (near stigma) to the basal end, generated by the temporal differences in fertilization. The dominant developing seeds at the distal end cause the abortion of others through the production and diffusion of an aborting agent. When the dominance hierarchy of the siblings is not intense, pods are formed with more than one seed. We argue that the positively skewed distribution of seeds per pod is not due to maternal regulation but is a result of sibling rivalry. We propose that this sibling rivalry is generated by genetic differences in pollen grain fitness and disucss the results in the context of parent-offspring conflict.
Lo, Sassoum; Muñoz-Amatriaín, María; Boukar, Ousmane; Herniter, Ira; Cisse, Ndiaga; Guo, Yi-Ning; Roberts, Philip A; Xu, Shizhong; Fatokun, Christian; Close, Timothy J
2018-04-19
Cowpea (Vigna unguiculata L. Walp) is a warm-season legume with a genetically diverse gene-pool composed of wild and cultivated forms. Cowpea domestication involved considerable phenotypic changes from the wild progenitor, including reduction of pod shattering, increased organ size, and changes in flowering time. Little is known about the genetic basis underlying these changes. In this study, 215 recombinant inbred lines derived from a cross between a cultivated and a wild cowpea accession were used to evaluate nine domestication-related traits (pod shattering, peduncle length, flower color, days to flowering, 100-seed weight, pod length, leaf length, leaf width and seed number per pod). A high-density genetic map containing 17,739 single nucleotide polymorphisms was constructed and used to identify 16 quantitative trait loci (QTL) for these nine traits. Based on annotations of the cowpea reference genome, genes within these regions are reported. Four regions with clusters of QTL were identified, including one on chromosome 8 related to increased organ size. This study provides new knowledge of the genomic regions controlling domestication-related traits in cowpea as well as candidate genes underlying those QTL. This information can help to exploit wild relatives in cowpea breeding programs.
NASA Astrophysics Data System (ADS)
Nilahayati; Rosmayati; Hanafiah, D. S.; Harahap, F.
2018-02-01
The objective of the research was to determine the selection criteria in Kipas Putih Soybean with gamma rays irradiation in M3 generation. In this study there are four populations namely population 0 Gray (control), 100 Gray, 200 Gray and 300 Gray. The results showed that high genotypic coefficient of variation (GCV) was obtained on the number of pods and seed weight per plant in population 200 Gy, number of branches on 100 Gy and 300 Gy, number of pods and seed weight per plants 100 and 200 Gy, moderate GCV in number of branches on 100 and 300 Gy while other characters such as plant height, numbers of branches on 200 Gy, flowering and harvest age have narrow GCV criteria. High heritability values are found in 300 Gy on plant height, number of branches 300 Gy, number of pods and seed weight per plant 200 Gy, days to flower 200 Gy and 300 Gy and days to harvest of all doses. Based on the genetic variabiliy and heritability, characters that can be used as selection criteria in this study is number of pods and seeds weight per plant, days to flower and days to harvest.
USDA-ARS?s Scientific Manuscript database
Cacao (Theobroma cacao L.) is a native crop of the Americas; however severe losses due to frosty pod (FP) [Moniliophthora roreri (Cif. and Par.)], and black pod (BP) [Phytophthora palmivora (Butl.) Butl.] have reduced cacao in the Americas to only 13.0% of world production. Agronomic practices to co...
NASA Astrophysics Data System (ADS)
Rahayu, M.; Bande, LOS; Hasan, A.; Yuswana, A.; Rinambo, F.
2018-02-01
Soybean (Glycine max L.) is one of the most important crops which production continues to be improved in all areas of soybean cultivation centers in an effort to maintain the availability of soybean foods, including Southeast Sulawesi. The purpose of this study was to analyze the contribution of pod borer pests to soybean crop production. Methods of direct observation were made on observed variables, including species and population of pest pod borer, intensity, and crop production. The result that found four types of pod borer pests are Nezara viridula, Riptortus linearis, Etiella zinckenella, and Leptocorisa acuta, each with a different population and contribution to the intensity of pod damage. The result of path analysis showed that directly population of N. viridula (61.14) and E. zinckenella (66.44) gave positive contribution in increasing pod damage, by 0.332 and 0.502 respectively, while the negative contribution was shown by population of R. linearis and L. acuta. Damage of the pod causes increased production of low soybean is only about 0.202, therefore required appropriate control techniques to control pod borer pests populations in soybean crops.
2011-10-14
For example, with southern resident killer whales , re-sighting a specific pod (or sub-pod) member is likely only if that pod (or sub-pod) has been...remaining four clusters are seen infrequently, a situation similar to pod-specific differences in sighting rates for northern resident killer whales (Ford...Satellite tracking reveals distinct movement patterns for Type B and Type C killer whales in the southern Ross Sea, Antarctica. Polar Biology 31:1461
NASA Astrophysics Data System (ADS)
Sung, Hong-Gye
This research focuses on the time-accurate simulation and analysis of the unsteady flowfield in an integrated rocket-ramjet engine (IRR) and combustion dynamics of a swirl-stabilized gas turbine engine. The primary objectives are: (1) to establish a unified computational framework for studying unsteady flow and flame dynamics in ramjet propulsion systems and gas turbine combustion chambers, and (2) to investigate the parameters and mechanisms responsible for driving flow oscillations. The first part of the thesis deals with a complete axi-symmetric IRR engine. The domain of concern includes a supersonic inlet diffuser, a combustion chamber, and an exhaust nozzle. This study focused on the physical mechanism of the interaction between the oscillatory terminal shock in the inlet diffuser and the flame in the combustion chamber. In addition, the flow and ignition transitions from the booster to the sustainer phase were analyzed comprehensively. Even though the coupling between the inlet dynamics and the unsteady motions of flame shows that they are closely correlated, fortunately, those couplings are out of phase with a phase lag of 90 degrees, which compensates for the amplification of the pressure fluctuation in the inlet. The second part of the thesis treats the combustion dynamics of a lean-premixed gas turbine swirl injector. A three-dimensional computation method utilizing the message passing interface (MPI) Parallel architecture and large-eddy-simulation technique was applied. Vortex breakdown in the swirling flow is clearly visualized and explained on theoretical bases. The unsteady turbulent flame dynamics are carefully simulated so that the flow motion can be characterized in detail. It was observed that some fuel lumps escape from the primary combustion zone, and move downstream and consequently produce hot spots and large vortical structures in the azimuthal direction. The correlation between pressure oscillation and unsteady heat release is examined by both the spatial and temporal Rayleigh parameters. In addition, basis modes of the unsteady turbulent flame are characterized using proper orthogonal decomposition (POD) analysis.
Ryder, Robert T.; Qiang, Jin; McCabe, Peter J.; Nuccio, Vito F.; Persits, Felix
2012-01-01
This report discusses the geologic framework and petroleum geology used to assess undiscovered petroleum resources in the Bohaiwan basin province for the 2000 World Energy Assessment Project of the U.S. Geological Survey. The Bohaiwan basin in northeastern China is the largest petroleum-producing region in China. Two total petroleum systems have been identified in the basin. The first, the Shahejie&ndashShahejie/Guantao/Wumishan Total Petroleum System, involves oil and gas generated from mature pods of lacustrine source rock that are associated with six major rift-controlled subbasins. Two assessment units are defined in this total petroleum system: (1) a Tertiary lacustrine assessment unit consisting of sandstone reservoirs interbedded with lacustrine shale source rocks, and (2) a pre-Tertiary buried hills assessment unit consisting of carbonate reservoirs that are overlain unconformably by Tertiary lacustrine shale source rocks. The second total petroleum system identified in the Bohaiwan basin is the Carboniferous/Permian Coal–Paleozoic Total Petroleum System, a hypothetical total petroleum system involving natural gas generated from multiple pods of thermally mature coal beds. Low-permeability Permian sandstones and possibly Carboniferous coal beds are the reservoir rocks. Most of the natural gas is inferred to be trapped in continuous accumulations near the center of the subbasins. This total petroleum system is largely unexplored and has good potential for undiscovered gas accumulations. One assessment unit, coal-sourced gas, is defined in this total petroleum system.
High-Power Actuation from Molecular Photoswitches in Enantiomerically Paired Soft Springs.
Aßhoff, Sarah J; Lancia, Federico; Iamsaard, Supitchaya; Matt, Benjamin; Kudernac, Tibor; Fletcher, Stephen P; Katsonis, Nathalie
2017-03-13
Motion in plants often relies on dynamic helical systems as seen in coiling tendrils, spasmoneme springs, and the opening of chiral seedpods. Developing nanotechnology that would allow molecular-level phenomena to drive such movements in artificial systems remains a scientific challenge. Herein, we describe a soft device that uses nanoscale information to mimic seedpod opening. The system exploits a fundamental mechanism of stimuli-responsive deformation in plants, namely that inflexible elements with specific orientations are integrated into a stimuli-responsive matrix. The device is operated by isomerization of a light-responsive molecular switch that drives the twisting of strips of liquid-crystal elastomers. The strips twist in opposite directions and work against each other until the pod pops open from stress. This mechanism allows the photoisomerization of molecular switches to stimulate rapid shape changes at the macroscale and thus to maximize actuation power. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.
On 3D flow-structures behind an inclined plate
NASA Astrophysics Data System (ADS)
Uruba, Václav; Pavlík, David; Procházka, Pavel; Skála, Vladislav; Kopecký, Václav
Stereo PIV measurements has been performed behind the inclined plate, angle of attack 5 and 10 deg. Occurrence and dynamics of streamwise structures behind the plate trailing edge have been studied in details using POD method. The streamwise structures are represented by vortices and low- and highvelocity regions, probably streaks. The obtained results support the hypothesis of an airfoil-flow force interaction by Hoffman and Johnson [1,2].
de Oliveira Junior, José Oswaldo; de Freitas, Milena Fernandes; Bullara de Andrade, Carolina; Chacur, Marucia; Ashmawi, Hazem Adel
2016-01-01
Tramadol is a drug used to treat moderate to severe pain. It is known to present a peripheral effect, but the local mechanisms underlying its actions remain unclear. The role of peripheral opioid receptors in postoperative pain is not well understood. In the present study, we examined the peripheral opioid receptors to determine the local effect of tramadol in a plantar incision pain model. Rats were subjected to plantar incision and divided into four groups on postoperative day (POD) 1: SF_SF, 0.9% NaCl injected into the right hindpaw; SF_TraI, 0.9% NaCl and tramadol injected into the right hindpaw; SF_TraC, 0.9% NaCl and tramadol injected into the contralateral hindpaw; and Nal_Tra, naloxone and tramadol injected into the ipsilateral hindpaw. To determine the animals' nociceptive threshold, mechanical hyperalgesia was measured before incision, on POD1 before treatment and at 15, 30, 45, and 60 minutes after the incision. The same procedure was repeated on the POD2. The expression levels of μ-opioid receptor (MOR) and δ-opioid receptor (DOR) were obtained through immunoblotting assays in the lumbar dorsal root ganglia (L3-L6) in naïve rats and 1, 2, 3, and 7 days after the incision. Our results showed that the plantar incision was able to cause an increase in mechanical hyperalgesia and that tramadol reversed this hyperalgesia on POD1 and POD2. Tramadol injections in the contralateral paw did not affect the animals' nociceptive threshold. Naloxone was able to antagonize the tramadol effect partially on POD1 and completely on POD2. The DOR expression increased on POD2, POD3, and POD7, whereas the MOR expression did not change. Together, our results show that tramadol promoted a local analgesic effect in the postoperative pain model that was antagonized by naloxone in POD2, alongside the increase of DOR expression.
Srour, Nadine; Daroub, Hamza; Toufeili, Imad; Olabi, Ammar
2016-07-01
This work aimed at formulating a carob-based milk beverage and assessing its chemical and sensory properties. Six varieties of carob pods, each processed into roasted and unroasted powders, were used to develop 12 prototypes of the beverage. Chemical and physico-chemical analyses (moisture, ash, fibre, protein, sugars, total-phenolics, total-antioxidants, water activity and colour) and sensory tests were conducted. The variety of carob pod had a significant effect on all chemical variables in carob powders (P < 0.01), except for sugars, and when incorporated in the beverage, on moisture, total phenolics, total antioxidant activity and colour parameters (L, a, b; P-values < 0.001). Roasting treatment significantly increased fibre, total phenolics, total antioxidant activity (P-values < 0.001), fructose, glucose (P-values < 0.05), and a-value levels (P < 0.01), significantly lowered moisture (P < 0.05), water activity, L- and b-values (P-values < 0.001) in carob powders; and significantly increased the beverage's total phenolics, a-value (P-values < 0.001) and total antioxidant activity (P < 0.01). Roasting treatment significantly increased the beverage's acceptability ratings. Beverages formulated with roasted carob powder had higher ratings for level of residue, colour, caramel odour, mocha odour and flavour, roasted coffee odour and flavour, viscosity mouthfeel and bitter aftertaste. Principal component analysis was conducted; PC1 and PC2 separated attributes according to roasting treatment and variety of carob pods, respectively. The use of Akkari roasted and Baladi Ikleem el Kharoob roasted to formulate a carob-based milk beverage is recommended. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.
Multipurpose Pressure Vessel Scanner and Photon Doppler Velocimetry
NASA Technical Reports Server (NTRS)
Ellis, Tayera
2015-01-01
Critical flight hardware typically undergoes a series of nondestructive evaluation methods to screen for defects before it is integrated into the flight system. Conventionally, pressure vessels have been inspected for flaws using a technique known as fluorescent dye penetrant, which is biased to inspector interpretation. An alternate method known as eddy current is automated and can detect small cracks better than dye penetrant. A new multipurpose pressure vessel scanner has been developed to perform internal and external eddy current scanning, laser profilometry, and thickness mapping on pressure vessels. Before this system can be implemented throughout industry, a probability of detection (POD) study needs to be performed to validate the system's eddy current crack/flaw capabilities. The POD sample set will consist of 6 flight-like metal pressure vessel liners with defects of known size. Preparation for the POD includes sample set fabrication, system operation, procedure development, and eddy current settings optimization. For this, collaborating with subject matter experts was required. This technical paper details the preparation activities leading up to the POD study currently scheduled for winter 2015/2016. Once validated, this system will be a proven innovation for increasing the safety and reliability of necessary flight hardware. Additionally, testing of frangible joint requires Photon Doppler Velocimetry (PDV) and Digital Image Correlation instrumentation. There is often noise associated with PDV data, which necessitates a frequency modulation (FM) signal-to-noise pre-test. Generally, FM radio works by varying the carrier frequency and mixing it with a fixed frequency source, creating a beat frequency which is represented by audio frequency that can be heard between about 20 to 20,000 Hz. Similarly, PDV reflects a shifted frequency (a phenomenon known as the Doppler Effect) from a moving source and mixes it with a fixed source frequency, which results in a beat frequency. However, for PDV, discerning the signal from the noise is difficult without a moving source to induce the modulation. A rotating wheel is currently being used as the moving source but its configuration is impractical and has cumbersome placement inside the current frangible joint test cell. As a way to combat this problem and verify a satisfactory signal-to-noise ratio, a reflective moving crystal piezo will be used to modulate a beat frequency, and an absorptive target will be used to block the signal in order to determine any back reflection coming from the probe and discern the true signal-to-noise ratio. The piezo will be mounted and inserted onto the test table on an extendable telescopic antenna grounded by a magnetic base in the test zone. This piezo configuration will be more compatible within the test zone and allow for easy removal of the disk following acceptable signal verification and prior to frangible joint tests.
Variables Affecting Probability of Detection in Bolt Hole Eddy Current Inspection
NASA Astrophysics Data System (ADS)
Lemire, H.; Krause, T. W.; Bunn, M.; Butcher, D. J.
2009-03-01
Physical variables affecting probability of detection (POD) in a bolt-hole eddy current inspection were examined. The POD study involved simulated bolt holes in 7075-T6 aluminum coupons representative of wing areas on CC-130 and CP-140 aircraft. The data were obtained from 24 inspectors who inspected 468 coupons, containing a subset of coupons with 45 electric discharge machined notches and 72 laboratory grown fatigue cracks located at the inner surface corner of the bi-layer structures. A comparison of physical features of cracks and notches in light of skin depth effects and probe geometry was used to identify length rather than depth as the significant variable producing signal variation. Probability of detection based on length produced similar results for the two discontinuity types, except at lengths less than 0.4 mm, where POD for cracks was found to be higher than that of notches.
Precise Orbit Determination of BeiDou Navigation Satellite System
NASA Astrophysics Data System (ADS)
He, Lina; Ge, Maorong; Wang, Jiexian; Wickert, Jens; Schuh, Harald
2013-04-01
China has been developing its own independent satellite navigation system since decades. Now the COMPASS system, also known as BeiDou, is emerging and gaining more and more interest and attention in the worldwide GNSS communities. The current regional BeiDou system is ready for its operational service around the end of 2012 with a constellation including five Geostationary Earth Orbit satellites (GEO), five Inclined Geosynchronous Orbit satellites (IGSO) and four Medium Earth orbit (MEO) satellites in operation. Besides the open service with positioning accuracy of around 10m which is free to civilian users, both precise relative positioning, and precise point positioning are demonstrated as well. In order to enhance the BeiDou precise positioning service, Precise Orbit Determination (POD) which is essential of any satellite navigation system has been investigated and studied thoroughly. To further improving the orbits of different types of satellites, we study the impact of network coverage on POD data products by comparing results from tracking networks over the Chinese territory, Asian-Pacific, Asian and of global scale. Furthermore, we concentrate on the improvement of involving MEOs on the orbit quality of GEOs and IGSOs. POD with and without MEOs are undertaken and results are analyzed. Finally, integer ambiguity resolution which brings highly improvement on orbits and positions with GPS data is also carried out and its effect on POD data products is assessed and discussed in detail. Seven weeks of BeiDou data from a ground tracking network, deployed by Wuhan University is employed in this study. The test constellation includes four GEO, five IGSO and two MEO satellites in operation. The three-day solution approach is employed to enhance its strength due to the limited coverage of the tracking network and the small movement of most of the satellites. A number of tracking scenarios and processing schemas are identified and processed and overlapping orbit differences are utilized to qualify the estimated orbits and clocks. The results show that GEO orbits, especially the along-track component, can be significantly improved by extending the tracking network in China along longitude direction, whereas IGSOs gain more improvement if the tracking network extends in latitude. For the current tracking network, deploying tracking stations on the eastern side, for example in New Zealand and/or in Hawaii, will significantly reduce along-track biases of GEOs on the same side. The involvement of MEOs and ambiguity-fixing also make the orbits better but rather moderate. Key words: BeiDou, precise orbit determination (POD), tracking network, ambiguity-fixing
Fischinger, Stephanie Anastasia; Schulze, Joachim
2010-05-01
Nodule CO2 fixation is of pivotal importance for N2 fixation. The process provides malate for bacteroids and oxaloacetate for nitrogen assimilation. The hypothesis of the present paper was that grain legume nodules would adapt to higher plant N demand and more restricted carbon availability at pod formation through increased nodule CO2 fixation and a more efficient N2 fixation. Growth, N2 fixation, and nodule composition during vegetative growth and at pod formation were studied in pea plants (Pisum sativum L.). In parallel experiments, 15N2 and 13CO2 uptake, as well as nodule hydrogen and CO2 release, was measured. Plants at pod formation showed higher growth rates and N2 fixation per plant when compared with vegetative growth. The specific activity of active nodules was about 25% higher at pod formation. The higher nodule activity was accompanied by higher amino acid concentration in nodules and xylem sap with a higher share of asparagine. Nodule 13CO2 fixation was increased at pod formation, both per plant and per 15N2 fixed unit. However, malate concentration in nodules was only 40% of that during vegetative growth and succinate was no longer detectable. The data indicate that increased N2 fixation at pod formation is connected with strongly increased nodule CO2 fixation. While the sugar concentration in nodules at pod formation was not altered, the concentration of organic acids, namely malate and succinate, was significantly lower. It is concluded that strategies to improve the capability of nodules to fix CO2 and form organic acids might prolong intensive N2 fixation into the later stages of pod formation and pod filling in grain legumes.
A single overnight stay is possible for most patients undergoing robotic partial nephrectomy.
Abaza, Ronney; Shah, Ketul
2013-02-01
To evaluate establishment of overnight stay only as sufficient after robotic partial nephrectomy (RPN). Stated benefits of minimally invasive surgery include reduced hospitalization, but published hospital stays after laparoscopic or robotic partial nephrectomy are not significantly less than with open surgery. We developed a clinical pathway targeting discharge on postoperative day (POD) 1 after RPN of any complexity. We reviewed all RPNs by a single surgeon since instituting our clinical pathway, including ambulation and diet the night of surgery, avoidance of intravenous narcotics and drains, and catheter removal on POD 1 before discharge. Targeted discharge was not modified regardless of RPN complexity. A total of 150 consecutive patients underwent 160 RPNs with 35 hilar tumors and 26 with segmental, and 33 with no artery clamping. Three had solitary kidneys, and 8 underwent multiple (range, 2-4) RPNs. Mean patient age was 57 years (range, 22-89 years), and body mass index was 32 kg/m(2) (range, 18-54 kg/m(2)). Mean tumor size was 3.6 cm (range, 1.0-11.0; median, 3.2 cm), and the RENAL (radius, exophytic/endophytic, nearness to collecting system, anterior/posterior, and location) nephrometry score was 8 (range, 4-12; median, 8). Mean warm ischemia time was 12.1 minutes (range, 0-30.0 minutes). Mean preoperative and discharge creatinine were 0.9 mg/dL (range, 0.43-2.79 mg/dL) and 1.13 mg/dL (range, 0.56-2.93 mg/dL). All patients ambulated on POD 0. One patient required one dose of intravenous narcotic. Mean length of stay was 1.1 days, with 145 (97%) discharged on POD 1, of which only 4 (2.7%) were readmitted within 30 days. Discharge on POD 1 is feasible in most RPN patients regardless of complexity. Readmission rate was low, indicating that longer admissions may not prevent complications when patients meeting discharge criteria go home on POD 1. Copyright © 2013 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Tian, X.; Xie, Z.; Liu, Y.; Cai, Z.; Fu, Y.; Zhang, H.; Feng, L.
2014-12-01
We have developed a novel framework ("Tan-Tracker") for assimilating observations of atmospheric CO2 concentrations, based on the POD-based (proper orthogonal decomposition) ensemble four-dimensional variational data assimilation method (PODEn4DVar). The high flexibility and the high computational efficiency of the PODEn4DVar approach allow us to include both the atmospheric CO2 concentrations and the surface CO2 fluxes as part of the large state vector to be simultaneously estimated from assimilation of atmospheric CO2 observations. Compared to most modern top-down flux inversion approaches, where only surface fluxes are considered as control variables, one major advantage of our joint data assimilation system is that, in principle, no assumption on perfect transport models is needed. In addition, the possibility for Tan-Tracker to use a complete dynamic model to consistently describe the time evolution of CO2 surface fluxes (CFs) and the atmospheric CO2 concentrations represents a better use of observation information for recycling the analyses at each assimilation step in order to improve the forecasts for the following assimilations. An experimental Tan-Tracker system has been built based on a complete augmented dynamical model, where (1) the surface atmosphere CO2 exchanges are prescribed by using a persistent forecasting model for the scaling factors of the first-guess net CO2 surface fluxes and (2) the atmospheric CO2 transport is simulated by using the GEOS-Chem three-dimensional global chemistry transport model. Observing system simulation experiments (OSSEs) for assimilating synthetic in situ observations of surface CO2 concentrations are carefully designed to evaluate the effectiveness of the Tan-Tracker system. In particular, detailed comparisons are made with its simplified version (referred to as TT-S) with only CFs taken as the prognostic variables. It is found that our Tan-Tracker system is capable of outperforming TT-S with higher assimilation precision for both CO2 concentrations and CO2 fluxes, mainly due to the simultaneous estimation of CO2 concentrations and CFs in our Tan-Tracker data assimilation system. A experiment for assimilating the real dry-air column CO2 retrievals (XCO2) from the Japanese Greenhouse Gases Observation Satellite (GOSAT) further demonstrates its potential wide applications.
NASA Astrophysics Data System (ADS)
Nay, S. M.; D'Amore, D. V.
2009-12-01
The coastal temperate rainforest (CTR) along the northwest coast of North America is a large and complex mosaic of forests and wetlands located on an undulating terrain ranging from sea level to thousands of meters in elevation. This biome stores a dynamic portion of the total carbon stock of North America. The fate of the terrestrial carbon stock is of concern due to the potential for mobilization and export of this store to both the atmosphere as carbon respiration flux and ocean as dissolved organic and inorganic carbon flux. Soil respiration is the largest export vector in the system and must be accurately measured to gain any comprehensive understanding of how carbon moves though this system. Suitable monitoring tools capable of measuring carbon fluxes at small spatial scales are essential for our understanding of carbon dynamics at larger spatial scales within this complex assemblage of ecosystems. We have adapted instrumentation and developed a sampling strategy for optimizing replication of soil respiration measurements to quantify differences among spatially complex landscape units of the CTR. We start with the design of the instrument to ease the technological, ergonomic and financial barriers that technicians encounter in monitoring the efflux of CO2 from the soil. Our sampling strategy optimizes the physical efforts of the field work and manages for the high variation of flux measurements encountered in this difficult environment of rough terrain, dense vegetation and wet climate. Our soil respirometer incorporates an infra-red gas analyzer (LiCor Inc. LI-820) and an 8300 cm3 soil respiration chamber; the device is durable, lightweight, easy to operate and can be built for under $5000 per unit. The modest unit price allows for a multiple unit fleet to be deployed and operated in an intensive field monitoring campaign. We use a large 346 cm2 collar to accommodate as much micro spatial variation as feasible and to facilitate repeated measures for tracking temporal trends. Our collar design minimizes root interference yet provides a highly stable platform for coupling with the respirometer. Meso-scale variability characterized by large down woody debris, wind throw pits and mounds and surface roots is negotiated with by a hexagonal array of seven collars at two meter spacing (sample pod). Landscape scale variability is managed through stratification and replication amongst ecosystem types arrayed across a hydrologic gradient from bogs to forested wetlands to upland forests. Our strategy has allowed us to gather data sets consisting of approximately 1800 total observations with approximately 600 measurements per replication per year. Mean coefficients of variation (CV) at the collar (micro-scale) were approximately 0.67. The pod level mean CV was reduced to approximately 0.29 at the pod (meso-scale). The CV at the vegetation strata were 0.43, 0.18 and 0.21 for bog, forested wetland and upland forest respectively. With temperature and hydrological data we are able to measure and model carbon dynamics in this large and complex environment. The analysis of variability at the three spatial scales has confirmed that our approach is capturing and constraining the variability.