Science.gov

Sample records for end-to-end spectrum reconstruction

  1. Automated End-to-End Workflow for Precise and Geo-accurate Reconstructions using Fiducial Markers

    NASA Astrophysics Data System (ADS)

    Rumpler, M.; Daftry, S.; Tscharf, A.; Prettenthaler, R.; Hoppe, C.; Mayer, G.; Bischof, H.

    2014-08-01

    Photogrammetric computer vision systems have been well established in many scientific and commercial fields during the last decades. Recent developments in image-based 3D reconstruction systems in conjunction with the availability of affordable high quality digital consumer grade cameras have resulted in an easy way of creating visually appealing 3D models. However, many of these methods require manual steps in the processing chain and for many photogrammetric applications such as mapping, recurrent topographic surveys or architectural and archaeological 3D documentations, high accuracy in a geo-coordinate system is required which often cannot be guaranteed. Hence, in this paper we present and advocate a fully automated end-to-end workflow for precise and geoaccurate 3D reconstructions using fiducial markers. We integrate an automatic camera calibration and georeferencing method into our image-based reconstruction pipeline based on binary-coded fiducial markers as artificial, individually identifiable landmarks in the scene. Additionally, we facilitate the use of these markers in conjunction with known ground control points (GCP) in the bundle adjustment, and use an online feedback method that allows assessment of the final reconstruction quality in terms of image overlap, ground sampling distance (GSD) and completeness, and thus provides flexibility to adopt the image acquisition strategy already during image recording. An extensive set of experiments is presented which demonstrate the accuracy benefits to obtain a highly accurate and geographically aligned reconstruction with an absolute point position uncertainty of about 1.5 times the ground sampling distance.

  2. Comparison of Reconstruction and Control algorithms on the ESO end-to-end simulator OCTOPUS

    NASA Astrophysics Data System (ADS)

    Montilla, I.; Béchet, C.; Lelouarn, M.; Correia, C.; Tallon, M.; Reyes, M.; Thiébaut, É.

    Extremely Large Telescopes are very challenging concerning their Adaptive Optics requirements. Their diameters, the specifications demanded by the science for which they are being designed for, and the planned use of Extreme Adaptive Optics systems, imply a huge increment in the number of degrees of freedom in the deformable mirrors. It is necessary to study new reconstruction algorithms to implement the real time control in Adaptive Optics at the required speed. We have studied the performance, applied to the case of the European ELT, of three different algorithms: the matrix-vector multiplication (MVM) algorithm, considered as a reference; the Fractal Iterative Method (FrIM); and the Fourier Transform Reconstructor (FTR). The algorithms have been tested on ESO's OCTOPUS software, which simulates the atmosphere, the deformable mirror, the sensor and the closed-loop control. The MVM is the default reconstruction and control method implemented in OCTOPUS, but it scales in O(N2) operations per loop so it is not considered as a fast algorithm for wave-front reconstruction and control on an Extremely Large Telescope. The two other methods are the fast algorithms studied in the E-ELT Design Study. The performance, as well as their response in the presence of noise and with various atmospheric conditions, has been compared using a Single Conjugate Adaptive Optics configuration for a 42 m diameter ELT, with a total amount of 5402 actuators. Those comparisons made on a common simulator allow to enhance the pros and cons of the various methods, and give us a better understanding of the type of reconstruction algorithm that an ELT demands.

  3. End-to-End Commitment

    NASA Technical Reports Server (NTRS)

    Newcomb, John

    2004-01-01

    The end-to-end test would verify the complex sequence of events from lander separation to landing. Due to the large distances involved and the significant delay time in sending a command and receiving verification, the lander needed to operate autonomously after it separated from the orbiter. It had to sense conditions, make decisions, and act accordingly. We were flying into a relatively unknown set of conditions-a Martian atmosphere of unknown pressure, density, and consistency to land on a surface of unknown altitude, and one which had an unknown bearing strength.

  4. End-to-End Radiographic Systems Simulation

    SciTech Connect

    Mathews, A.; Kwan, T.; Buescher, K.; Snell, C.; Adams, K.

    1999-07-23

    This is the final report of a one-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The objective of this project was to develop a validated end-to-end radiographic model that could be applied to both x-rays and protons. The specific objectives were to link hydrodynamic, transport, and magneto-hydrodynamic simulation software for purposes of modeling radiographic systems. In addition, optimization and analysis algorithms were to be developed to validate physical models and optimize the design of radiographic facilities.

  5. End-to-end power beaming model

    SciTech Connect

    Ponikvar, D.R.; Bell, J.P.; Schor, M.J.

    1994-12-31

    W.J. Schafer Associates, Inc. has produced an interactive end-to-end model of a laser power beaming system designed to deliver electrical power from a ground based free electron laser (FEL) to a satellite. The model includes a description of pertinent FEL physics, realistic atmospheric propagation effects, photovoltaic interactions for various semiconductor materials, and satellite onboard power conditioning. A detailed orbital model with graphical output is available, which visualizes the effect of electric propulsion for orbital reboost or orbit transfer. This flexible tool has been applied to specific examples of satellite battery charging for geostationary communication satellites, as well as parametric studies of photovoltaic cell performance. Preliminary results of system wavelength/power/aperture diameter trades will be presented.

  6. Evaluating Internet End-to-end Performance

    PubMed Central

    Wood, Fred B.; Cid, Victor H.; Siegel, Elliot R.

    1998-01-01

    Abstract Objective: An evaluation of Internet end-to-end performance was conducted for the purpose of better understanding the overall performance of Internet pathways typical of those used to access information in National Library of Medicine (NLM) databases and, by extension, other Internet-based biomedical information resources. Design: The evaluation used a three-level test strategy: 1) user testing to collect empirical data on Internet performance as perceived by users when accessing NLM Web-based databases, 2) technical testing to analyze the Internet paths between the NLM and the user's desktop computer terminal, and 3) technical testing between the NLM and the World Wide Web (“Web”) server computer at the user's institution to help characterize the relative performance of Internet pathways. Measurements: Time to download the front pages of NLM Web sites and conduct standardized searches of NLM databases, data transmission capacity between NLM and remote locations (known as the bulk transfer capacity [BTC], “ping” round-trip time as an indication of the latency of the network pathways, and the network routing of the data transmissions (number and sequencing of hops). Results: Based on 347 user tests spread over 16 locations, the median time per location to download the main NLM home page ranged from 2 to 59 seconds, and 1 to 24 seconds for the other NLM Web sites tested. The median time to conduct standardized searches and get search results ranged from 2 to 14 seconds for PubMed and 4 to 18 seconds for Internet Grateful Med. The overall problem rate was about 1 percent; that is, on the average, users experienced a problem once every 100 test measurements. The user terminal tests at five locations and Web host tests at 13 locations provided profiles of BTC, RTT, and network routing for both dial-up and fixed Internet connections. Conclusion: The evaluation framework provided a profile of typical Internet performance and insights into network

  7. CASTOR end-to-end monitoring

    NASA Astrophysics Data System (ADS)

    Rekatsinas, Theodoros; Duellmann, Dirk; Pokorski, Witold; Ponce, Sébastien; Rabaçal, Bartolomeu; Waldron, Dennis; Wojcieszuk, Jacek

    2010-04-01

    With the start of Large Hadron Collider approaching, storage and management of raw event data, as well as reconstruction and analysis data, is of crucial importance for the researchers. The CERN Advanced STORage system (CASTOR) is a hierarchical system developed at CERN, used to store physics production files and user files. CASTOR, as one of the essential software tools used by the LHC experiments, has to provide reliable services for storing and managing data. Monitoring of this complicated system is mandatory in order to assure its stable operation and improve its future performance. This paper presents the new monitoring system of CASTOR which provides operation and user request specific metrics. This system is build around a dedicated, optimized database schema. The schema is populated by PL/SQL procedures, which process a stream of incoming raw metadata from different CASTOR components, initially collected by the Distributed Logging Facility (DLF). A web interface has been developed for the visualization of the monitoring data. The different histograms and plots are created using PHP scripts which query the monitoring database.

  8. Applying Trustworthy Computing to End-to-End Electronic Voting

    ERIC Educational Resources Information Center

    Fink, Russell A.

    2010-01-01

    "End-to-End (E2E)" voting systems provide cryptographic proof that the voter's intention is captured, cast, and tallied correctly. While E2E systems guarantee integrity independent of software, most E2E systems rely on software to provide confidentiality, availability, authentication, and access control; thus, end-to-end integrity is not…

  9. Standardizing an End-to-end Accounting Service

    NASA Technical Reports Server (NTRS)

    Greenberg, Edward; Kazz, Greg

    2006-01-01

    Currently there are no space system standards available for space agencies to accomplish end-to-end accounting. Such a standard does not exist for spacecraft operations nor for tracing the relationship between the mission planning activities, the command sequences designed to perform those activities, the commands formulated to initiate those activities and the mission data and specifically the mission data products created by those activities. In order for space agencies to cross-support one another for data accountability/data tracing and for inter agency spacecraft to interoperate with each other, an international CCSDS standard for end-to-end data accountability/tracing needs to be developed. We will first describe the end-to-end accounting service model and functionality that supports the service. This model will describe how science plans that are ultimately transformed into commands can be associated with the telemetry products generated as a result of their execution. Moreover, the interaction between end-to-end accounting and service management will be explored. Finally, we will show how the standard end-to-end accounting service can be applied to a real life flight project i.e., the Mars Reconnaissance Orbiter project.

  10. Plastic end-to-end treatment of bulbar urethral stricture

    PubMed Central

    Hamza, Amir; Behrendt, Wolf; Tietze, Stefan

    2013-01-01

    For bulbar urethral strictures up to 2.5 cm in length, the one-stage urethral plastic surgery with stricture excision and direct end-to-end anastomosis remains the best procedure to guarantee a high success rate. This retrospective review shows the results of 21 patients who underwent bulbar end-to-end anastomosis from 2010–2013. In 20 cases (95.3%) good results were archived. The criteria of success were identified by pre- and postoperative radiological diagnostics and uroflowmetry. PMID:26504704

  11. Combining Simulation Tools for End-to-End Trajectory Optimization

    NASA Technical Reports Server (NTRS)

    Whitley, Ryan; Gutkowski, Jeffrey; Craig, Scott; Dawn, Tim; Williams, Jacobs; Stein, William B.; Litton, Daniel; Lugo, Rafael; Qu, Min

    2015-01-01

    Trajectory simulations with advanced optimization algorithms are invaluable tools in the process of designing spacecraft. Due to the need for complex models, simulations are often highly tailored to the needs of the particular program or mission. NASA's Orion and SLS programs are no exception. While independent analyses are valuable to assess individual spacecraft capabilities, a complete end-to-end trajectory from launch to splashdown maximizes potential performance and ensures a continuous solution. In order to obtain end-to-end capability, Orion's in-space tool (Copernicus) was made to interface directly with the SLS's ascent tool (POST2) and a new tool to optimize the full problem by operating both simulations simultaneously was born.

  12. LWS/SET End-to-End Data System

    NASA Technical Reports Server (NTRS)

    Giffin, Geoff; Sherman, Barry; Colon, Gilberto (Technical Monitor)

    2002-01-01

    This paper describes the concept for the End-to-End Data System that will support NASA's Living With a Star Space Environment Testbed missions. NASA has initiated the Living With a Star (LWS) Program to develop a better scientific understanding to address the aspects of the connected Sun-Earth system that affect life and society. A principal goal of the program is to bridge the gap.between science, engineering, and user application communities. The Space Environment Testbed (SET) Project is one element of LWS. The Project will enable future science, operational, and commercial objectives in space and atmospheric environments by improving engineering approaches to the accommodation and/or mitigation of the effects of solar variability on technological systems. The End-to-end data system allows investigators to access the SET control center, command their experiments, and receive data from their experiments back at their home facility, using the Internet. The logical functioning of major components of the end-to-end data system are described, including the GSFC Payload Operations Control Center (POCC), SET Payloads, the GSFC SET Simulation Lab, SET Experiment PI Facilities, and Host Systems. Host Spacecraft Operations Control Centers (SOCC) and the Host Spacecraft are essential links in the end-to-end data system, but are not directly under the control of the SET Project. Formal interfaces will be established between these entities and elements of the SET Project. The paper describes data flow through the system, from PI facilities connecting to the SET operations center via the Internet, communications to SET carriers and experiments via host systems, to telemetry returns to investigators from their flight experiments. It also outlines the techniques that will be used to meet mission requirements, while holding development and operational costs to a minimum. Additional information is included in the original extended abstract.

  13. Measurements and analysis of end-to-end Internet dynamics

    SciTech Connect

    Paxson, V

    1997-04-01

    Accurately characterizing end-to-end Internet dynamics - the performance that a user actually obtains from the lengthy series of network links that comprise a path through the Internet - is exceptionally difficult, due to the network`s immense heterogeneity. At the heart of this work is a `measurement framework` in which a number of sites around the Internet host a specialized measurement service. By coordinating `probes` between pairs of these sites one can measure end-to-end behavior along O(N{sup 2}) paths for a framework consisting of N sites. Consequently, one obtains a superlinear scaling that allows measuring a rich cross-section of Internet behavior without requiring huge numbers of observation points. 37 sites participated in this study, allowing the author to measure more than 1,000 distinct Internet paths. The first part of this work looks at the behavior of end-to-end routing: the series of routers over which a connection`s packets travel. Based on 40,000 measurements made using this framework, the author analyzes: routing `pathologies` such as loops, outages, and flutter; the stability of routes over time; and the symmetry of routing along the two directions of an end-to-end path. The author finds that pathologies increased significantly over the course of 1995 and that Internet paths are heavily dominated by a single route. The second part of this work studies end-to-end Internet packet dynamics. The author analyzes 20,000 TCP transfers of 100 Kbyte each to investigate the performance of both the TCP endpoints and the Internet paths. The measurements used for this part of the study are much richer than those for the first part, but require a great degree of attention to issues of calibration, which are addressed by applying self-consistency checks to the measurements whenever possible. The author finds that packet filters are capable of a wide range of measurement errors, some of which, if undetected, can significantly taint subsequent analysis.

  14. Reconfigurable Protocol Sensing in an End-to-End Demonstration

    NASA Technical Reports Server (NTRS)

    Okino, Clayton M.; Gray, Andrew; Schoolcraft, Joshua

    2006-01-01

    In this work, we present sensing performance using an architecture for a reconfigurable protocol chip for spacebased applications. Toward utilizing the IP packet architecture, utilizing data link layer framing structures for multiplexed data on a channel are the targeted application considered for demonstration purposes. Specifically, we examine three common framing standards and present the sensing performance of these standards and their relative de-correlation metrics. Some analysis is performed to investigate the impact of lossy links. Finally, we present results on a demonstration platform that integrated reconfigurable sensing technology into the Ground Station Interface Device (GRID) for End-to-End IP demonstrations in space.

  15. On routing algorithms with end-to-end delay guarantees

    SciTech Connect

    Rao, N.S.V.; Batsell, S.G.

    1998-11-01

    The authors consider the transmission of a message of size r from a source to a destination with guarantees on the end-to-end delay over a computer network with n nodes and m links. There are three sources of delays: (a) propagation delays along the links, (b) delays due to bandwidth availability on the links, and (c) queuing delays at the intermediate nodes. First, the authors consider that delays on various links and nodes are given as functions of the message size. If the delay in (b) is a non-increasing function of the bandwidth, they propose O(m{sup 2} + mn log n) time algorithm to compute a path with the minimum end-to-end delay for any given message size r. They then consider that the queuing delay in (c) is a random variable correlated with the message size according to an unknown distribution. At each node, the measurements of queuing delays and message sizes are available. They propose two algorithms to compute paths whose delays are close to optimal delays with a high probability, irrespective of the distribution of the delays, and based entirely on the measurements of sufficient size.

  16. End-to-end network/application performance troubleshooting methodology

    SciTech Connect

    Wu, Wenji; Bobyshev, Andrey; Bowden, Mark; Crawford, Matt; Demar, Phil; Grigaliunas, Vyto; Grigoriev, Maxim; Petravick, Don; /Fermilab

    2007-09-01

    The computing models for HEP experiments are globally distributed and grid-based. Obstacles to good network performance arise from many causes and can be a major impediment to the success of the computing models for HEP experiments. Factors that affect overall network/application performance exist on the hosts themselves (application software, operating system, hardware), in the local area networks that support the end systems, and within the wide area networks. Since the computer and network systems are globally distributed, it can be very difficult to locate and identify the factors that are hurting application performance. In this paper, we present an end-to-end network/application performance troubleshooting methodology developed and in use at Fermilab. The core of our approach is to narrow down the problem scope with a divide and conquer strategy. The overall complex problem is split into two distinct sub-problems: host diagnosis and tuning, and network path analysis. After satisfactorily evaluating, and if necessary resolving, each sub-problem, we conduct end-to-end performance analysis and diagnosis. The paper will discuss tools we use as part of the methodology. The long term objective of the effort is to enable site administrators and end users to conduct much of the troubleshooting themselves, before (or instead of) calling upon network and operating system 'wizards,' who are always in short supply.

  17. Recirculating Linac Acceleration - End-to-End Simulation

    SciTech Connect

    Alex Bogacz

    2010-03-01

    A conceptual design of a high-pass-number Recirculating Linear Accelerator (RLA) for muons is presented. The scheme involves three superconducting linacs (201 MHz): a single pass linear Pre-accelerator followed by a pair multi-pass (4.5-pass) 'Dogbone' RLAs. Acceleration starts after ionization cooling at 220 MeV/c and proceeds to 12.6 GeV. The Pre-accelerator captures a large muon phase space and accelerates muons to relativistic energies, while adiabatically decreasing the phase-space volume, so that effective acceleration in the RLA is possible. The RLA further compresses and shapes up the longitudinal and transverse phase-spaces, while increasing the energy. Appropriate choice of multi-pass linac optics based on FODO focusing assures large number of passes in the RLA. The proposed 'Dogbone' configuration facilitates simultaneous acceleration of both mu± species through the requirement of mirror symmetric optics of the return 'droplet' arcs. Finally, presented end-to-end simulation validates the efficiency and acceptance of the accelerator system.

  18. Key management for large scale end-to-end encryption

    SciTech Connect

    Witzke, E.L.

    1994-07-01

    Symmetric end-to-end encryption requires separate keys for each pair of communicating confidants. This is a problem of Order N{sup 2}. Other factors, such as multiple sessions per pair of confidants and multiple encryption points in the ISO Reference Model complicate key management by linear factors. Public-key encryption can reduce the number of keys managed to a linear problem which is good for scaleability of key management, but comes with complicating issues and performance penalties. Authenticity is the primary ingredient of key management. If each potential pair of communicating confidants can authenticate data from each other, then any number of public encryption keys of any type can be communicated with requisite integrity. These public encryption keys can be used with the corresponding private keys to exchange symmetric cryptovariables for high data rate privacy protection. The Digital Signature Standard (DSS), which has been adopted by the United States Government, has both public and private components, similar to a public-key cryptosystem. The Digital Signature Algorithm of the DSS is intended for authenticity but not for secrecy. In this paper, the authors will show how the use of the Digital Signature Algorithm combined with both symmetric and asymmetric (public-key) encryption techniques can provide a practical solution to key management scaleability problems, by reducing the key management complexity to a problem of order N, without sacrificing the encryption speed necessary to operate in high performance networks.

  19. Quality metrics for measuring end-to-end distortion in packet-switched video communication systems

    NASA Astrophysics Data System (ADS)

    Eisenberg, Yiftach; Zhai, Fan; Pappas, Thrasyvoulos N.; Berry, Randall; Katsaggelos, Aggelos K.

    2004-06-01

    A critical component of any video transmission system is an objective metric for evaluating the quality of the video signal as it is seen by the end-user. In packet-based communication systems, such as a wireless channel or the Internet, the quality of the received signal is affected by both signal compression and packet losses. Due to the probabilistic nature of the channel, the distortion in the reconstructed signal is a random variable. In addition, the quality of the reconstructed signal depends on the error concealment strategy. A common approach is to use the expected mean squared error of the end-to-end distortion as the performance metric. It can be shown that this approach leads to unpredictable perceptual artifacts. A better approach is to account for both the mean and the variance of the end-to-end distortion. We explore the perceptual benefits of this approach. By accounting for the variance of the distortion, the difference between the transmitted and the reconstructed signal can be decreased without a significant increase in the expected value of the distortion. Our experimental results indicate that for low to moderate probability of loss, the proposed approach offers significant advantages over strictly minimizing the expected distortion. We demonstrate that controlling the variance of the distortion limits perceptually annoying artifacts such as persistent errors.

  20. OGC standards for end-to-end sensor network integration

    NASA Astrophysics Data System (ADS)

    Headley, K. L.; Broering, A.; O'Reilly, T. C.; Toma, D.; Del Rio, J.; Bermudez, L. E.; Zedlitz, J.; Johnson, G.; Edgington, D.

    2010-12-01

    technology, and can communicate with any sensor whose protocol can be described by a SID. The SID interpreter transfers retrieved sensor data to a Sensor Observation Service, and transforms tasks submitted to a Sensor Planning Service to actual sensor commands. The proposed SWE PUCK protocol complements SID by providing a standard way to associate a sensor with a SID, thereby completely automating the sensor integration process. PUCK protocol is implemented in sensor firmware, and provides a means to retrieve a universally unique identifer, metadata and other information from the device itself through its communication interface. Thus the SID interpreter can retrieve a SID directly from the sensor through PUCK protocol. Alternatively the interpreter can retrieve the sensor’s SID from an external source, based on the unique sensor ID provided by PUCK protocol. In this presentation, we describe the end-to-end integration of several commercial oceanographic instruments into a sensor network using PUCK, SID and SWE services. We also present a user-friendly, graphical tool to generate SIDs and tools to visualize sensor data.

  1. Data analysis pipeline for EChO end-to-end simulations

    NASA Astrophysics Data System (ADS)

    Waldmann, Ingo P.; Pascale, E.

    2015-12-01

    Atmospheric spectroscopy of extrasolar planets is an intricate business. Atmospheric signatures typically require a photometric precision of 1×10-4 in flux over several hours. Such precision demands high instrument stability as well as an understanding of stellar variability and an optimal data reduction and removal of systematic noise. In the context of the EChO mission concept, we here discuss the data reduction and analysis pipeline developed for the EChO end-to-end simulator EChOSim. We present and discuss the step by step procedures required in order to obtain the final exoplanetary spectrum from the EChOSim `raw data' using a simulated observation of the secondary eclipse of the hot-Neptune 55 Cnc e.

  2. Modified end-to-end anastomosis for the treatment of congenital tracheal stenosis with a bridging bronchus.

    PubMed

    Stock, Cameron; Nathan, Meena; Murray, Ryan; Rahbar, Reza; Fynn-Thompson, Francis

    2015-01-01

    An infant with a ventricular septal defect; Vertebral anomalies, Anal atresia, Cardiac anomalies, Tracho Esophageal fistula (TEF), Renal anomalies, Limb anomalies syndrome; and tracheal stenosis with a bridging bronchus underwent repair of the ventricular septal defect and trachea-bronchial reconstruction at age 11 months. Herein we describe our surgical approach to resection of the bridging bronchus and a technique using a modified end-to-end tracheal anastomosis for the correction of this complex anomaly. PMID:25555968

  3. Experimental demonstration of software defined data center optical networks with Tbps end-to-end tunability

    NASA Astrophysics Data System (ADS)

    Zhao, Yongli; Zhang, Jie; Ji, Yuefeng; Li, Hui; Wang, Huitao; Ge, Chao

    2015-10-01

    The end-to-end tunability is important to provision elastic channel for the burst traffic of data center optical networks. Then, how to complete the end-to-end tunability based on elastic optical networks? Software defined networking (SDN) based end-to-end tunability solution is proposed for software defined data center optical networks, and the protocol extension and implementation procedure are designed accordingly. For the first time, the flexible grid all optical networks with Tbps end-to-end tunable transport and switch system have been online demonstrated for data center interconnection, which are controlled by OpenDayLight (ODL) based controller. The performance of the end-to-end tunable transport and switch system has been evaluated with wavelength number tuning, bit rate tuning, and transmit power tuning procedure.

  4. MRI simulation: end-to-end testing for prostate radiation therapy using geometric pelvic MRI phantoms.

    PubMed

    Sun, Jidi; Dowling, Jason; Pichler, Peter; Menk, Fred; Rivest-Henault, David; Lambert, Jonathan; Parker, Joel; Arm, Jameen; Best, Leah; Martin, Jarad; Denham, James W; Greer, Peter B

    2015-04-21

    To clinically implement MRI simulation or MRI-alone treatment planning requires comprehensive end-to-end testing to ensure an accurate process. The purpose of this study was to design and build a geometric phantom simulating a human male pelvis that is suitable for both CT and MRI scanning and use it to test geometric and dosimetric aspects of MRI simulation including treatment planning and digitally reconstructed radiograph (DRR) generation.A liquid filled pelvic shaped phantom with simulated pelvic organs was scanned in a 3T MRI simulator with dedicated radiotherapy couch-top, laser bridge and pelvic coil mounts. A second phantom with the same external shape but with an internal distortion grid was used to quantify the distortion of the MR image. Both phantoms were also CT scanned as the gold-standard for both geometry and dosimetry. Deformable image registration was used to quantify the MR distortion. Dose comparison was made using a seven-field IMRT plan developed on the CT scan with the fluences copied to the MR image and recalculated using bulk electron densities. Without correction the maximum distortion of the MR compared with the CT scan was 7.5 mm across the pelvis, while this was reduced to 2.6 and 1.7 mm by the vendor's 2D and 3D correction algorithms, respectively. Within the locations of the internal organs of interest, the distortion was <1.5 and <1 mm with 2D and 3D correction algorithms, respectively. The dose at the prostate isocentre calculated on CT and MRI images differed by 0.01% (1.1 cGy). Positioning shifts were within 1 mm when setup was performed using MRI generated DRRs compared to setup using CT DRRs.The MRI pelvic phantom allows end-to-end testing of the MRI simulation workflow with comparison to the gold-standard CT based process. MRI simulation was found to be geometrically accurate with organ dimensions, dose distributions and DRR based setup within acceptable limits compared to CT. PMID:25803177

  5. MRI simulation: end-to-end testing for prostate radiation therapy using geometric pelvic MRI phantoms

    NASA Astrophysics Data System (ADS)

    Sun, Jidi; Dowling, Jason; Pichler, Peter; Menk, Fred; Rivest-Henault, David; Lambert, Jonathan; Parker, Joel; Arm, Jameen; Best, Leah; Martin, Jarad; Denham, James W.; Greer, Peter B.

    2015-04-01

    To clinically implement MRI simulation or MRI-alone treatment planning requires comprehensive end-to-end testing to ensure an accurate process. The purpose of this study was to design and build a geometric phantom simulating a human male pelvis that is suitable for both CT and MRI scanning and use it to test geometric and dosimetric aspects of MRI simulation including treatment planning and digitally reconstructed radiograph (DRR) generation. A liquid filled pelvic shaped phantom with simulated pelvic organs was scanned in a 3T MRI simulator with dedicated radiotherapy couch-top, laser bridge and pelvic coil mounts. A second phantom with the same external shape but with an internal distortion grid was used to quantify the distortion of the MR image. Both phantoms were also CT scanned as the gold-standard for both geometry and dosimetry. Deformable image registration was used to quantify the MR distortion. Dose comparison was made using a seven-field IMRT plan developed on the CT scan with the fluences copied to the MR image and recalculated using bulk electron densities. Without correction the maximum distortion of the MR compared with the CT scan was 7.5 mm across the pelvis, while this was reduced to 2.6 and 1.7 mm by the vendor’s 2D and 3D correction algorithms, respectively. Within the locations of the internal organs of interest, the distortion was <1.5 and <1 mm with 2D and 3D correction algorithms, respectively. The dose at the prostate isocentre calculated on CT and MRI images differed by 0.01% (1.1 cGy). Positioning shifts were within 1 mm when setup was performed using MRI generated DRRs compared to setup using CT DRRs. The MRI pelvic phantom allows end-to-end testing of the MRI simulation workflow with comparison to the gold-standard CT based process. MRI simulation was found to be geometrically accurate with organ dimensions, dose distributions and DRR based setup within acceptable limits compared to CT.

  6. A Computer Program for the Distribution of End-to-End Distances in Polymer Molecules

    ERIC Educational Resources Information Center

    Doorne, William Van; And Others

    1976-01-01

    Describes a Fortran program that illustrates how the end-to-end distances in randomly coiled polymer molecules is affected by varying the number and lengths of chains and the angles between them. (MLH)

  7. End-to-End Models for Effects of System Noise on LIMS Analysis of Igneous Rocks

    SciTech Connect

    Clegg, Samuel M; Bender, Steven; Wiens, R. C.; Carmosino, Marco L; Speicher, Elly A; Dyar, M. D.

    2010-12-23

    The ChemCam instrument on the Mars Science Laboratory will be the first extraterrestial deployment of laser-induced breakdown spectroscopy (UBS) for remote geochemical analysis. LIBS instruments are also being proposed for future NASA missions. In quantitative LIBS applications using multivariate analysis techniques, it is essential to understand the effects of key instrument parameters and their variability on the elemental predictions. Baseline experiments were run on a laboratory instrument in conditions reproducing ChemCam performance on Mars. These experiments employed Nd:YAG laser producing 17 mJ/pulse on target and an with a 200 {micro}m FWHM spot size on the surface of a sample. The emission is collected by a telescope, imaged on a fiber optic and then interfaced to a demultiplexer capable of >40% transmission into each spectrometer. We report here on an integrated end-to-end system performance model that simulates the effects of output signal degradation that might result from the input signal chain and the impact on multivariate model predictions. There are two approaches to modifying signal to noise (SNR): degrade the signal and/or increase the noise. Ishibashi used a much smaller data set to show that the addition of noise had significant impact while degradation of spectral resolution had much less impact on accuracy and precision. Here, we specifically focus on aspects of remote LIBS instrument performance as they relate to various types of signal degradation. To assess the sensitivity of LIBS analysis to signal-to-noise ratio (SNR) and spectral resolution, the signal in each spectrum from a suite of 50 laboratory spectra of igneous rocks was variably degraded by increasing the peak widths (simulating misalignment) and decreasing the spectral amplitude (simulating decreases in SNR).

  8. A NASA Climate Model Data Services (CDS) End-to-End System to Support Reanalysis Intercomparison

    NASA Astrophysics Data System (ADS)

    Carriere, L.; Potter, G. L.; McInerney, M.; Nadeau, D.; Shen, Y.; Duffy, D.; Schnase, J. L.; Maxwell, T. P.; Huffer, E.

    2014-12-01

    The NASA Climate Model Data Service (CDS) and the NASA Center for Climate Simulation (NCCS) are collaborating to provide an end-to-end system for the comparative study of the major Reanalysis projects, currently, ECMWF ERA-Interim, NASA/GMAO MERRA, NOAA/NCEP CFSR, NOAA/ESRL 20CR, and JMA JRA25. Components of the system include the full spectrum of Climate Model Data Services; Data, Compute Services, Data Services, Analytic Services and Knowledge Services. The Data includes standard Reanalysis model output, and will be expanded to include gridded observations, and gridded Innovations (O-A and O-F). The NCCS High Performance Science Cloud provides the compute environment (storage, servers, and network). Data Services are provided through an Earth System Grid Federation (ESGF) data node complete with Live Access Server (LAS), Web Map Service (WMS) and Ultrascale Visualization Climate Data Analysis Tools (UV-CDAT) for visualization, as well as a collaborative interface through the Earth System CoG. Analytic Services include UV-CDAT for analysis and MERRA/AS, accessed via the CDS API, for computation services, both part of the CDS Climate Analytics as a Service (CAaaS). Knowledge Services include access to an Ontology browser, ODISEES, for metadata search and data retrieval. The result is a system that provides the ability for both reanalysis scientists and those scientists in need of reanalysis output to identify the data of interest, compare, compute, visualize, and research without the need for transferring large volumes of data, performing time consuming format conversions, and writing code for frequently run computations and visualizations.

  9. An end-to-end communications architecture for condition-based maintenance applications

    NASA Astrophysics Data System (ADS)

    Kroculick, Joseph

    2014-06-01

    This paper explores challenges in implementing an end-to-end communications architecture for Condition-Based Maintenance Plus (CBM+) data transmission which aligns with the Army's Network Modernization Strategy. The Army's Network Modernization strategy is based on rolling out network capabilities which connect the smallest unit and Soldier level to enterprise systems. CBM+ is a continuous improvement initiative over the life cycle of a weapon system or equipment to improve the reliability and maintenance effectiveness of Department of Defense (DoD) systems. CBM+ depends on the collection, processing and transport of large volumes of data. An important capability that enables CBM+ is an end-to-end network architecture that enables data to be uploaded from the platform at the tactical level to enterprise data analysis tools. To connect end-to-end maintenance processes in the Army's supply chain, a CBM+ network capability can be developed from available network capabilities.

  10. End-to-end Coronagraphic Modeling Including a Low-order Wavefront Sensor

    NASA Technical Reports Server (NTRS)

    Krist, John E.; Trauger, John T.; Unwin, Stephen C.; Traub, Wesley A.

    2012-01-01

    To evaluate space-based coronagraphic techniques, end-to-end modeling is necessary to simulate realistic fields containing speckles caused by wavefront errors. Real systems will suffer from pointing errors and thermal and motioninduced mechanical stresses that introduce time-variable wavefront aberrations that can reduce the field contrast. A loworder wavefront sensor (LOWFS) is needed to measure these changes at a sufficiently high rate to maintain the contrast level during observations. We implement here a LOWFS and corresponding low-order wavefront control subsystem (LOWFCS) in end-to-end models of a space-based coronagraph. Our goal is to be able to accurately duplicate the effect of the LOWFS+LOWFCS without explicitly evaluating the end-to-end model at numerous time steps.

  11. A Robust Method to Integrate End-to-End Mission Architecture Optimization Tools

    NASA Technical Reports Server (NTRS)

    Lugo, Rafael; Litton, Daniel; Qu, Min; Shidner, Jeremy; Powell, Richard

    2016-01-01

    End-to-end mission simulations include multiple phases of flight. For example, an end-to-end Mars mission simulation may include launch from Earth, interplanetary transit to Mars and entry, descent and landing. Each phase of flight is optimized to meet specified constraints and often depend on and impact subsequent phases. The design and optimization tools and methodologies used to combine different aspects of end-to-end framework and their impact on mission planning are presented. This work focuses on a robust implementation of a Multidisciplinary Design Analysis and Optimization (MDAO) method that offers the flexibility to quickly adapt to changing mission design requirements. Different simulations tailored to the liftoff, ascent, and atmospheric entry phases of a trajectory are integrated and optimized in the MDAO program Isight, which provides the user a graphical interface to link simulation inputs and outputs. This approach provides many advantages to mission planners, as it is easily adapted to different mission scenarios and can improve the understanding of the integrated system performance within a particular mission configuration. A Mars direct entry mission using the Space Launch System (SLS) is presented as a generic end-to-end case study. For the given launch period, the SLS launch performance is traded for improved orbit geometry alignment, resulting in an optimized a net payload that is comparable to that in the SLS Mission Planner's Guide.

  12. Scalable end-to-end encryption technology for supra-gigabit/second networking

    SciTech Connect

    Pierson, L.G.; Tarman, T.D.; Witzke, E.L.

    1997-05-01

    End-to-end encryption can protect proprietary information as it passes through a complex inter-city computer network, even if the intermediate systems are untrusted. This technique involves encrypting the body of computer messages while leaving network addressing and control information unencrypted for processing by intermediate network nodes. Because high speed implementations of end-to-end encryption with easy key management for standard network protocols are unavailable, this technique is not widely used today. Specifically, no end-to-end encryptors exist to protect Asynchronous Transfer Mode (ATM) traffic, nor to protect Switched Multi-megabit Data Service (SMDS), which is the first ``Broadband Integrated Services Digital Network`` (BISDN) service now being used by long distance telephone companies. This encryption technology is required for the protection of data in transit between industrial sites and central Massively Parallel Supercomputing Centers over high bandwidth, variable bit rate (BISDN) services. This research effort investigated techniques to scale end-to-end encryption technology from today`s state of the art ({approximately} 0.001 Gb/s) to 2.4 Gb/s and higher. A cryptosystem design has been developed which scales for implementation beyond SONET OC-48 (2.4Gb/s) data rates. A prototype for use with OC-3 (0.155 Gb/s) ATM variable bit rate services was developed.

  13. End-to-End Data System Architecture for the Space Station Biological Research Project

    NASA Technical Reports Server (NTRS)

    Mian, Arshad; Scimemi, Sam; Adeni, Kaiser; Picinich, Lou; Ramos, Rubin (Technical Monitor)

    1998-01-01

    The Space Station Biological Research Project (SSBRP) Is developing hardware referred to as the "facility" for providing life sciences research capability on the International Space Station. This hardware includes several biological specimen habitats, habitat holding racks, a centrifuge and a glovebox. An SSBRP end to end data system architecture has been developed to allow command and control of the facility from the ground, either with crew assistance or autonomously. The data system will be capable of handling commands, sensor data, and video from multiple cameras. The data will traverse through several onboard and ground networks and processing entities including the SSBRP and Space Station onboard and ground data systems. A large number of onboard and ground (,entities of the data system are being developed by the Space Station Program, other NASA centers and the International Partners. The SSBRP part of the system which includes the habitats, holding racks, and the ground operations center, User Operations Facility (UOF) will be developed by a multitude of geographically distributed development organizations. The SSBRP has the responsibility to define the end to end data and communications systems to make the interfaces manageable and verifiable with multiple contractors with widely varying development constraints and schedules. This paper provides an overview of the SSBRP end-to-end data system. Specifically, it describes the hardware, software and functional interactions of individual systems, and interface requirements among various entities of the end-to-end system.

  14. End-to-end network models encompassing terrestrial, wireless, and satellite components

    NASA Astrophysics Data System (ADS)

    Boyarko, Chandler L.; Britton, John S.; Flores, Phil E.; Lambert, Charles B.; Pendzick, John M.; Ryan, Christopher M.; Shankman, Gordon L.; Williams, Ramon P.

    2004-08-01

    Development of network models that reflect true end-to-end architectures such as the Transformational Communications Architecture need to encompass terrestrial, wireless and satellite component to truly represent all of the complexities in a world wide communications network. Use of best-in-class tools including OPNET, Satellite Tool Kit (STK), Popkin System Architect and their well known XML-friendly definitions, such as OPNET Modeler's Data Type Description (DTD), or socket-based data transfer modules, such as STK/Connect, enable the sharing of data between applications for more rapid development of end-to-end system architectures and a more complete system design. By sharing the results of and integrating best-in-class tools we are able to (1) promote sharing of data, (2) enhance the fidelity of our results and (3) allow network and application performance to be viewed in the context of the entire enterprise and its processes.

  15. The International Space Station Alpha (ISSA) End-to-End On-Orbit Maintenance Process Flow

    NASA Technical Reports Server (NTRS)

    Zingrebe, Kenneth W., II

    1995-01-01

    As a tool for construction and refinement of the on-orbit maintenance system to sustain the International Space Station Alpha (ISSA), the Mission Operations Directorate (MOD) developed an end to-end on-orbit maintenance process flow. This paper discusses and demonstrates that process flow. This tool is being used by MOD to identify areas which require further work in preparation for MOD's role in the conduct of on-orbit maintenance operations.

  16. Surgical Outcome of Excision and End-to-End Anastomosis for Bulbar Urethral Stricture

    PubMed Central

    Suh, Jun-Gyo; Choi, Woo Suk; Paick, Jae-Seung

    2013-01-01

    Purpose Although direct-vision internal urethrotomy can be performed for the management of short, bulbar urethral strictures, excision and end-to-end anastomosis remains the best procedure to guarantee a high success rate. We performed a retrospective evaluation of patients who underwent bulbar end-to-end anastomosis to assess the factors affecting surgical outcome. Materials and Methods We reviewed 33 patients with an average age of 55 years who underwent bulbar end-to-end anastomosis. Stricture etiology was blunt perineal trauma (54.6%), iatrogenic (24.2%), idiopathic (12.1%), and infection (9.1%). A total of 21 patients (63.6%) underwent urethrotomy, dilation, or multiple treatments before referral to our center. Clinical outcome was considered a treatment failure when any postoperative instrumentation was needed. Results Mean operation time was 151 minutes (range, 100 to 215 minutes) and mean excised stricture length was 1.5 cm (range, 0.8 to 2.3 cm). At a mean follow-up of 42.6 months (range, 8 to 96 months), 29 patients (87.9%) were symptom-free and required no further procedure. Strictures recurred in 4 patients (12.1%) within 5 months after surgery. Of four recurrences, one patient was managed successfully by urethrotomy, whereas the remaining three did not respond to urethrotomy or dilation and required additional urethroplasty. The recurrence rate was significantly higher in the patients with nontraumatic causes (iatrogenic in three, infection in one patient) than in the patients with traumatic etiology. Conclusions Excision and end-to-end anastomosis for short, bulbar urethral stricture has an acceptable success rate of 87.9%. However, careful consideration is needed to decide on the surgical procedure if the stricture etiology is nontraumatic. PMID:23878686

  17. End-to-end calculation of the radiation characteristics of VVER-1000 spent fuel assemblies

    NASA Astrophysics Data System (ADS)

    Linge, I. I.; Mitenkova, E. F.; Novikov, N. V.

    2012-12-01

    The results of end-to-end calculation of the radiation characteristics of VVER-1000 spent nuclear fuel are presented. Details of formation of neutron and gamma-radiation sources are analyzed. Distributed sources of different types of radiation are considered. A comparative analysis of calculated radiation characteristics is performed with the use of nuclear data from different ENDF/B and EAF files and ANSI/ANS and ICRP standards.

  18. CHEETAH: circuit-switched high-speed end-to-end transport architecture

    NASA Astrophysics Data System (ADS)

    Veeraraghavan, Malathi; Zheng, Xuan; Lee, Hyuk; Gardner, M.; Feng, Wuchun

    2003-10-01

    Leveraging the dominance of Ethernet in LANs and SONET/SDH in MANs and WANs, we propose a service called CHEETAH (Circuit-switched High-speed End-to-End Transport ArcHitecture). The service concept is to provide end hosts with high-speed, end-to-end circuit connectivity on a call-by-call shared basis, where a "circuit" consists of Ethernet segments at the ends that are mapped into Ethernet-over-SONET long-distance circuits. This paper focuses on the file-transfer application for such circuits. For this application, the CHEETAH service is proposed as an add-on to the primary Internet access service already in place for enterprise hosts. This allows an end host that is sending a file to first attempt setting up an end-to-end Ethernet/EoS circuit, and if rejected, fall back to the TCP/IP path. If the circuit setup is successful, the end host will enjoy a much shorter file-transfer delay than on the TCP/IP path. To determine the conditions under which an end host with access to the CHEETAH service should attempt circuit setup, we analyze mean file-transfer delays as a function of call blocking probability in the circuit-switched network, probability of packet loss in the IP network, round-trip times, link rates, and so on.

  19. An end-to-end approach to developing biological and chemical detector requirements

    NASA Astrophysics Data System (ADS)

    Teclemariam, Nerayo P.; Purvis, Liston K.; Foltz, Greg W.; West, Todd; Edwards, Donna M.; Fruetel, Julia A.; Gleason, Nathaniel J.

    2009-05-01

    Effective defense against chemical and biological threats requires an "end-to-end" strategy that encompasses the entire problem space, from threat assessment and target hardening to response planning and recovery. A key element of the strategy is the definition of appropriate system requirements for surveillance and detection of threat agents. Our end-to-end approach to venue chem/bio defense is captured in the Facilities Weapons of Mass Destruction Decision Analysis Capability (FacDAC), an integrated system-of-systems toolset that can be used to generate requirements across all stages of detector development. For example, in the early stage of detector development the approach can be used to develop performance targets (e.g., sensitivity, selectivity, false positive rate) to provide guidance on what technologies to pursue. In the development phase, after a detector technology has been selected, the approach can aid in determining performance trade-offs and down-selection of competing technologies. During the application stage, the approach can be employed to design optimal defensive architectures that make the best use of available technology to maximize system performance. This presentation will discuss the end-to-end approach to defining detector requirements and demonstrate the capabilities of the FacDAC toolset using examples from a number of studies for the Department of Homeland Security.

  20. End-to-end distribution for a wormlike chain in arbitrary dimensions.

    PubMed

    Mehraeen, Shafigh; Sudhanshu, Bariz; Koslover, Elena F; Spakowitz, Andrew J

    2008-06-01

    We construct an efficient methodology for calculating wormlike chain statistics in arbitrary D dimensions over all chain rigidities, from fully rigid to completely flexible. The structure of our exact analytical solution for the end-to-end distribution function for a wormlike chain in arbitrary D dimensions in Fourier-Laplace space (i.e., Fourier-transformed end position and Laplace-transformed chain length) adopts the form of an infinite continued fraction, which is advantageous for its compact structure and stability for numerical implementation. We then proceed to present a step-by-step methodology for performing the Fourier-Laplace inversion in order to make full use of our results in general applications. Asymptotic methods for evaluating the Laplace inversion (power-law expansion and Rayleigh-Schrödinger perturbation theory) are employed in order to improve the accuracy of the numerical inversions of the end-to-end distribution function in real space. We adapt our results to the evaluation of the single-chain structure factor, rendering simple, closed-form expressions that facilitate comparison with scattering experiments. Using our techniques, the accuracy of the end-to-end distribution function is enhanced up to the limit of the machine precision. We demonstrate the utility of our methodology with realizations of the chain statistics, giving a general methodology that can be applied to a wide range of biophysical problems. PMID:18643291

  1. End-to-end distribution for a wormlike chain in arbitrary dimensions

    NASA Astrophysics Data System (ADS)

    Mehraeen, Shafigh; Sudhanshu, Bariz; Koslover, Elena F.; Spakowitz, Andrew J.

    2008-06-01

    We construct an efficient methodology for calculating wormlike chain statistics in arbitrary D dimensions over all chain rigidities, from fully rigid to completely flexible. The structure of our exact analytical solution for the end-to-end distribution function for a wormlike chain in arbitrary D dimensions in Fourier-Laplace space (i.e., Fourier-transformed end position and Laplace-transformed chain length) adopts the form of an infinite continued fraction, which is advantageous for its compact structure and stability for numerical implementation. We then proceed to present a step-by-step methodology for performing the Fourier-Laplace inversion in order to make full use of our results in general applications. Asymptotic methods for evaluating the Laplace inversion (power-law expansion and Rayleigh-Schrödinger perturbation theory) are employed in order to improve the accuracy of the numerical inversions of the end-to-end distribution function in real space. We adapt our results to the evaluation of the single-chain structure factor, rendering simple, closed-form expressions that facilitate comparison with scattering experiments. Using our techniques, the accuracy of the end-to-end distribution function is enhanced up to the limit of the machine precision. We demonstrate the utility of our methodology with realizations of the chain statistics, giving a general methodology that can be applied to a wide range of biophysical problems.

  2. End-to-end security in telemedical networks--a practical guideline.

    PubMed

    Wozak, Florian; Schabetsberger, Thomas; Ammmenwerth, Elske

    2007-01-01

    The interconnection of medical networks in different healthcare institutions will be constantly increasing over the next few years, which will require concepts for securing medical data during transfer, since transmitting patient related data via potentially insecure public networks is considered a violation of data privacy. The aim of our work was to develop a model-based approach towards end-to-end security which is defined as continuous security from point of origin to point of destination in a communication process. We show that end-to-end security must be seen as a holistic security concept, which comprises the following three major parts: authentication and access control, transport security, as well as system security. For integration into existing security infrastructures abuse case models were used, which extend UML use cases, by elements necessary to describe abusive interactions. Abuse case models can be constructed for each part mentioned above, allowing for potential security risks in communication from point of origin to point of destination to be identified and counteractive measures to be directly derived from the abuse case models. The model-based approach is a guideline to continuous risk assessment and improvement of end-to-end security in medical networks. Validity and relevance to practice will be systematically evaluated using close-to-reality test networks as well as in production environments. PMID:17097916

  3. Ocean Acidification Scientific Data Stewardship: An approach for end-to-end data management and integration

    NASA Astrophysics Data System (ADS)

    Arzayus, K. M.; Garcia, H. E.; Jiang, L.; Michael, P.

    2012-12-01

    As the designated Federal permanent oceanographic data center in the United States, NOAA's National Oceanographic Data Center (NODC) has been providing scientific stewardship for national and international marine environmental and ecosystem data for over 50 years. NODC is supporting NOAA's Ocean Acidification Program and the science community by providing end-to-end scientific data management of ocean acidification (OA) data, dedicated online data discovery, and user-friendly access to a diverse range of historical and modern OA and other chemical, physical, and biological oceanographic data. This effort is being catalyzed by the NOAA Ocean Acidification Program, but the intended reach is for the broader scientific ocean acidification community. The first three years of the project will be focused on infrastructure building. A complete ocean acidification data content standard is being developed to ensure that a full spectrum of ocean acidification data and metadata can be stored and utilized for optimal data discovery and access in usable data formats. We plan to develop a data access interface capable of allowing users to constrain their search based on real-time and delayed mode measured variables, scientific data quality, their observation types, the temporal coverage, methods, instruments, standards, collecting institutions, and the spatial coverage. In addition, NODC seeks to utilize the existing suite of international standards (including ISO 19115-2 and CF-compliant netCDF) to help our data producers use those standards for their data, and help our data consumers make use of the well-standardized metadata-rich data sets. These tools will be available through our NODC Ocean Acidification Scientific Data Stewardship (OADS) web page at http://www.nodc.noaa.gov/oceanacidification. NODC also has a goal to provide each archived dataset with a unique ID, to ensure a means of providing credit to the data provider. Working with partner institutions, such as the

  4. End-to-end modeling of the ozone mapping and profiler suite

    NASA Astrophysics Data System (ADS)

    McComas, Brian K.; Seftor, Colin; Remund, Quinn; Larsen, Jack; Wright, Carter; Raine, Erica

    2004-09-01

    The Ozone and Mapping Profiler Suite (OMPS) is an instrument suite in the National Polar-orbiting Operation Environmental Satellite System (NPOESS). The OMPS instrument is designed to globally retrieve both total column ozone and ozone profiles. To do this, OMPS consists of three sensors, two Nadir Instruments and one Limb Instrument. Each OMPS sensor has an End-to-End Model (ETEM) developed using the Toolkit for Remote Sensing, Analysis, Design, Evaluation, and Simulation (TRADES), a Ball Aerospace proprietary set of software tools developed in Matlab. The end-to-end modeling activities, which includes a radiative transfer model, the ETEM, and retrieval algorithms, have three fundamental objectives: sensor performance validation, aid in algorithm development, and algorithm robustness validation. The end-to-end modeling activities are key to showing sensor performance meets the system level Environmental Data Record (EDR) requirements. To do this, the ETEM incorporates sensor data; including point spread functions, stray light, dispersion, bandpass, and focal plane array (FPA) noise parameters. The sensor model characteristics are first implemented with predictions and updated as component test data becomes available. To evaluate the system"s EDR performance, the input radiance derived from the radiative transfer model is entered into the ETEM, which outputs a simulated image. The retrieval algorithms process the simulated image to determine the ozone amount. The system level EDR performance is determined by comparing the retrieved ozone amount with the truth, which was entered into the forward model. Additionally, the ETEM aids the algorithm development by simulating the expected sensor and calibration data with the expected noise characteristics. Finally, the algorithm robustness can be validated against extreme conditions using the ETEM.

  5. End-to-End Assessment of a Large Aperture Segmented Ultraviolet Optical Infrared (UVOIR) Telescope Architecture

    NASA Technical Reports Server (NTRS)

    Feinberg, Lee; Bolcar, Matt; Liu, Alice; Guyon, Olivier; Stark,Chris; Arenberg, Jon

    2016-01-01

    Key challenges of a future large aperture, segmented Ultraviolet Optical Infrared (UVOIR) Telescope capable of performing a spectroscopic survey of hundreds of Exoplanets will be sufficient stability to achieve 10-10 contrast measurements and sufficient throughput and sensitivity for high yield Exo-Earth spectroscopic detection. Our team has collectively assessed an optimized end to end architecture including a high throughput coronagraph capable of working with a segmented telescope, a cost-effective and heritage based stable segmented telescope, a control architecture that minimizes the amount of new technologies, and an Exo-Earth yield assessment to evaluate potential performance.

  6. Screening California Current fishery management scenarios using the Atlantis end-to-end ecosystem model

    NASA Astrophysics Data System (ADS)

    Kaplan, Isaac C.; Horne, Peter J.; Levin, Phillip S.

    2012-09-01

    End-to-end marine ecosystem models link climate and oceanography to the food web and human activities. These models can be used as forecasting tools, to strategically evaluate management options and to support ecosystem-based management. Here we report the results of such forecasts in the California Current, using an Atlantis end-to-end model. We worked collaboratively with fishery managers at NOAA’s regional offices and staff at the National Marine Sanctuaries (NMS) to explore the impact of fishery policies on management objectives at different spatial scales, from single Marine Sanctuaries to the entire Northern California Current. In addition to examining Status Quo management, we explored the consequences of several gear switching and spatial management scenarios. Of the scenarios that involved large scale management changes, no single scenario maximized all performance metrics. Any policy choice would involve trade-offs between stakeholder groups and policy goals. For example, a coast-wide 25% gear shift from trawl to pot or longline appeared to be one possible compromise between an increase in spatial management (which sacrificed revenue) and scenarios such as the one consolidating bottom impacts to deeper areas (which did not perform substantially differently from Status Quo). Judged on a coast-wide scale, most of the scenarios that involved minor or local management changes (e.g. within Monterey Bay NMS only) yielded results similar to Status Quo. When impacts did occur in these cases, they often involved local interactions that were difficult to predict a priori based solely on fishing patterns. However, judged on the local scale, deviation from Status Quo did emerge, particularly for metrics related to stationary species or variables (i.e. habitat and local metrics of landed value or bycatch). We also found that isolated management actions within Monterey Bay NMS would cause local fishers to pay a cost for conservation, in terms of reductions in landed

  7. End-to-end planning and scheduling systems technology for space operations

    NASA Astrophysics Data System (ADS)

    Moe, Karen L.

    1992-08-01

    Consideration is given to planning and scheduling operations concepts from an end-to-end perspective, through both mission operations and institutional support functions. An operations concept is proposed which is based on a flexible request language used to state resource requirements and mission constraints to a scheduling system. The language has the potential to evolve into an international standard for exchanging service request information on international space networks. The key benefit of the flexible scheduling request concept is the shift of a significant conflict resolution effort from humans to computers, reducing the time for generating a week's worth of schedules to hours instead of days.

  8. End-to-end planning and scheduling systems technology for space operations

    NASA Technical Reports Server (NTRS)

    Moe, Karen L.

    1992-01-01

    Consideration is given to planning and scheduling operations concepts from an end-to-end perspective, through both mission operations and institutional support functions. An operations concept is proposed which is based on a flexible request language used to state resource requirements and mission constraints to a scheduling system. The language has the potential to evolve into an international standard for exchanging service request information on international space networks. The key benefit of the flexible scheduling request concept is the shift of a significant conflict resolution effort from humans to computers, reducing the time for generating a week's worth of schedules to hours instead of days.

  9. Satellite/Terrestrial Networks: End-to-End Communication Interoperability Quality of Service Experiments

    NASA Technical Reports Server (NTRS)

    Ivancic, William D.

    1998-01-01

    Various issues associated with satellite/terrestrial end-to-end communication interoperability are presented in viewgraph form. Specific topics include: 1) Quality of service; 2) ATM performance characteristics; 3) MPEG-2 transport stream mapping to AAL-5; 4) Observation and discussion of compressed video tests over ATM; 5) Digital video over satellites status; 6) Satellite link configurations; 7) MPEG-2 over ATM with binomial errors; 8) MPEG-2 over ATM channel characteristics; 8) MPEG-2 over ATM over emulated satellites; 9) MPEG-2 transport stream with errors; and a 10) Dual decoder test.

  10. Information adaptive system of NEEDS. [of NASA End to End Data System

    NASA Technical Reports Server (NTRS)

    Howle, W. M., Jr.; Kelly, W. L.

    1979-01-01

    The NASA End-to-End Data System (NEEDS) program was initiated by NASA to improve significantly the state of the art in acquisition, processing, and distribution of space-acquired data for the mid-1980s and beyond. The information adaptive system (IAS) is a program element under NEEDS Phase II which addresses sensor specific processing on board the spacecraft. The IAS program is a logical first step toward smart sensors, and IAS developments - particularly the system components and key technology improvements - are applicable to future smart efforts. The paper describes the design goals and functional elements of the IAS. In addition, the schedule for IAS development and demonstration is discussed.

  11. EFFIS: and End-to-end Framework for Fusion Integrated Simulation

    SciTech Connect

    Cummings, Julian; Schwan, Karsten; Sim, Alexander S; Shoshani, Arie; Docan, Ciprian; Parashar, Manish; Klasky, Scott A; Podhorszki, Norbert

    2010-01-01

    The purpose of the Fusion Simulation Project is to develop a predictive capability for integrated modeling of magnetically confined burning plasmas. In support of this mission, the Center for Plasma Edge Simulation has developed an End-to-end Framework for Fusion Integrated Simulation (EFFIS) that combines critical computer science technologies in an effective manner to support leadership class computing and the coupling of complex plasma physics models. We describe here the main components of EFFIS and how they are being utilized to address our goal of integrated predictive plasma edge simulation.

  12. An End-To-End Test of A Simulated Nuclear Electric Propulsion System

    NASA Technical Reports Server (NTRS)

    VanDyke, Melissa; Hrbud, Ivana; Goddfellow, Keith; Rodgers, Stephen L. (Technical Monitor)

    2002-01-01

    The Safe Affordable Fission Engine (SAFE) test series addresses Phase I Space Fission Systems issues in it particular non-nuclear testing and system integration issues leading to the testing and non-nuclear demonstration of a 400-kW fully integrated flight unit. The first part of the SAFE 30 test series demonstrated operation of the simulated nuclear core and heat pipe system. Experimental data acquired in a number of different test scenarios will validate existing computational models, demonstrated system flexibility (fast start-ups, multiple start-ups/shut downs), simulate predictable failure modes and operating environments. The objective of the second part is to demonstrate an integrated propulsion system consisting of a core, conversion system and a thruster where the system converts thermal heat into jet power. This end-to-end system demonstration sets a precedent for ground testing of nuclear electric propulsion systems. The paper describes the SAFE 30 end-to-end system demonstration and its subsystems.

  13. A Bottom-up Route to a Chemically End-to-End Assembly of Nanocellulose Fibers.

    PubMed

    Yang, Han; van de Ven, Theo G M

    2016-06-13

    In this work, we take advantage of the rod-like structure of electrosterically stabilized nanocrystalline cellulose (ENCC, with a width of about 7 nm and a length of about 130 nm), which has dicarboxylated cellulose (DCC) chains protruding from both ends, providing electrosterical stability for ENCC particles, to chemically end-to-end assemble these particles into nanocellulose fibers. ENCC with shorter DCC chains can be obtained by a mild hydrolysis of ENCC with HCl, and subsequently the hydrolyzed ENCC (HENCC, with a width of about 6 nm and a length of about 120 nm) is suitable to be assembled into high aspect ratio nanofibers by chemically cross-linking HENCC from one end to another. Two sets of HENCC were prepared by carbodiimide-mediated formation of an alkyne and an azide derivative, respectively. Cross-linking these two sets of HENCC was performed by a click reaction. HENCCs were also end-to-end cross-linked by a bioconjugation reaction, with a diamine. From atomic force microscopy (AFM) images, about ten HENCC nanoparticles were cross-linked and formed high aspect ratio nanofibers with a width of about 6 nm and a length of more than 1 μm. PMID:27211496

  14. End-to-end validation process for the INTA-Nanosat-1B Attitude Control System

    NASA Astrophysics Data System (ADS)

    Polo, Óscar R.; Esteban, Segundo; Cercos, Lorenzo; Parra, Pablo; Angulo, Manuel

    2014-01-01

    This paper describes the end-to-end validation process for the Attitude Control Subsystem (ACS) of the satellite INTA-NanoSat-1B (NS-1B). This satellite was launched on July 2009 and it has been fully operative since then. The development of its ACS modules required an exhaustive integration and a system-level validation program. Some of the tests were centred on the validation of the drivers of sensors and actuators and were carried out over the flying model of the satellite. Others, more complex, constituted end-to-end tests where the concurrency of modules, the real-time control requirements and even the well-formedness of the telemetry data were verified. This work presents an incremental and highly automatised way for performing the ACS validation program based on two development suites and an end-to-end validation environment. The validation environment combines a Flat Satellite (FlatSat) configuration and a real-time emulator working in closed-loop. The FlatSat is built using the NS-1B Qualification Model (QM) hardware and it can run a complete version of the on-board software with the ACS modules fully integrated. The real-time emulator, running on an industrial PC, samples the actuation signals and emulates the sensors signals to close the control loop with the FlatSat. This validation environment constitutes a low-cost alternative to the classical three axes tilt table, with the advantage of being easily configured for working under specific orbit conditions, in accordance with any of the selected tests. The approach has been successfully applied to the NS-1B in order to verify different ACS modes under multiple orbit scenarios, providing an exhaustive coverage and reducing the risk of eventual errors during the satellite's lifetime. The strategy was applied also during the validation of the maintenance and reconfiguration procedures required once the satellite was launched. This paper describes in detail the complete ACS validation process that was

  15. Cyberinfrastructure to support Real-time, End-to-End, High Resolution, Localized Forecasting

    NASA Astrophysics Data System (ADS)

    Ramamurthy, M. K.; Lindholm, D.; Baltzer, T.; Domenico, B.

    2004-12-01

    From natural disasters such as flooding and forest fires to man-made disasters such as toxic gas releases, the impact of weather-influenced severe events on society can be profound. Understanding, predicting, and mitigating such local, mesoscale events calls for a cyberinfrastructure to integrate multidisciplinary data, tools, and services as well as the capability to generate and use high resolution data (such as wind and precipitation) from localized models. The need for such end to end systems -- including data collection, distribution, integration, assimilation, regionalized mesoscale modeling, analysis, and visualization -- has been realized to some extent in many academic and quasi-operational environments, especially for atmospheric sciences data. However, many challenges still remain in the integration and synthesis of data from multiple sources and the development of interoperable data systems and services across those disciplines. Over the years, the Unidata Program Center has developed several tools that have either directly or indirectly facilitated these local modeling activities. For example, the community is using Unidata technologies such as the Internet Data Distribution (IDD) system, Local Data Manger (LDM), decoders, netCDF libraries, Thematic Realtime Environmental Distributed Data Services (THREDDS), and the Integrated Data Viewer (IDV) in their real-time prediction efforts. In essence, these technologies for data reception and processing, local and remote access, cataloging, and analysis and visualization coupled with technologies from others in the community are becoming the foundation of a cyberinfrastructure to support an end-to-end regional forecasting system. To build on these capabilities, the Unidata Program Center is pleased to be a significant contributor to the Linked Environments for Atmospheric Discovery (LEAD) project, a NSF-funded multi-institutional large Information Technology Research effort. The goal of LEAD is to create an

  16. End-to-end performance analysis using engineering confidence models and a ground processor prototype

    NASA Astrophysics Data System (ADS)

    Kruse, Klaus-Werner; Sauer, Maximilian; Jäger, Thomas; Herzog, Alexandra; Schmitt, Michael; Huchler, Markus; Wallace, Kotska; Eisinger, Michael; Heliere, Arnaud; Lefebvre, Alain; Maher, Mat; Chang, Mark; Phillips, Tracy; Knight, Steve; de Goeij, Bryan T. G.; van der Knaap, Frits; Van't Hof, Adriaan

    2015-10-01

    The European Space Agency (ESA) and the Japan Aerospace Exploration Agency (JAXA) are co-operating to develop the EarthCARE satellite mission with the fundamental objective of improving the understanding of the processes involving clouds, aerosols and radiation in the Earth's atmosphere. The EarthCARE Multispectral Imager (MSI) is relatively compact for a space borne imager. As a consequence, the immediate point-spread function (PSF) of the instrument will be mainly determined by the diffraction caused by the relatively small optical aperture. In order to still achieve a high contrast image, de-convolution processing is applied to remove the impact of diffraction on the PSF. A Lucy-Richardson algorithm has been chosen for this purpose. This paper will describe the system setup and the necessary data pre-processing and post-processing steps applied in order to compare the end-to-end image quality with the L1b performance required by the science community.

  17. End-to-End Network Simulation Using a Site-Specific Radio Wave Propagation Model

    SciTech Connect

    Djouadi, Seddik M; Kuruganti, Phani Teja; Nutaro, James J

    2013-01-01

    The performance of systems that rely on a wireless network depends on the propagation environment in which that network operates. To predict how these systems and their supporting networks will perform, simulations must take into consideration the propagation environment and how this effects the performance of the wireless network. Network simulators typically use empirical models of the propagation environment. However, these models are not intended for, and cannot be used, to predict a wireless system will perform in a specific location, e.g., in the center of a particular city or the interior of a specific manufacturing facility. In this paper, we demonstrate how a site-specific propagation model and the NS3 simulator can be used to predict the end-to-end performance of a wireless network.

  18. End-to-End Assessment of a Large Aperture Segmented Ultraviolet Optical Infrared (UVOIR) Telescope Architecture

    NASA Technical Reports Server (NTRS)

    Feinberg, Lee; Rioux, Norman; Bolcar, Matthew; Liu, Alice; Guyon, Oliver; Stark, Chris; Arenberg, Jon

    2016-01-01

    Key challenges of a future large aperture, segmented Ultraviolet Optical Infrared (UVOIR) Telescope capable of performing a spectroscopic survey of hundreds of Exoplanets will be sufficient stability to achieve 10^-10 contrast measurements and sufficient throughput and sensitivity for high yield Exo-Earth spectroscopic detection. Our team has collectively assessed an optimized end to end architecture including a high throughput coronagraph capable of working with a segmented telescope, a cost-effective and heritage based stable segmented telescope, a control architecture that minimizes the amount of new technologies, and an Exo-Earth yield assessment to evaluate potential performance. These efforts are combined through integrated modeling, coronagraph evaluations, and Exo-Earth yield calculations to assess the potential performance of the selected architecture. In addition, we discusses the scalability of this architecture to larger apertures and the technological tall poles to enabling it.

  19. End-to-end interoperability and workflows from building architecture design to one or more simulations

    DOEpatents

    Chao, Tian-Jy; Kim, Younghun

    2015-02-10

    An end-to-end interoperability and workflows from building architecture design to one or more simulations, in one aspect, may comprise establishing a BIM enablement platform architecture. A data model defines data entities and entity relationships for enabling the interoperability and workflows. A data definition language may be implemented that defines and creates a table schema of a database associated with the data model. Data management services and/or application programming interfaces may be implemented for interacting with the data model. Web services may also be provided for interacting with the data model via the Web. A user interface may be implemented that communicates with users and uses the BIM enablement platform architecture, the data model, the data definition language, data management services and application programming interfaces to provide functions to the users to perform work related to building information management.

  20. The Kepler End-to-End Data Pipeline: From Photons to Far Away Worlds

    NASA Technical Reports Server (NTRS)

    Cooke, Brian; Thompson, Richard; Standley, Shaun

    2012-01-01

    Launched by NASA on 6 March 2009, the Kepler Mission has been observing more than 100,000 targets in a single patch of sky between the constellations Cygnus and Lyra almost continuously for the last two years looking for planetary systems using the transit method. As of October 2011, the Kepler spacecraft has collected and returned to Earth just over 290 GB of data, identifying 1235 planet candidates with 25 of these candidates confirmed as planets via ground observation. Extracting the telltale signature of a planetary system from stellar photometry where valid signal transients can be small as a 40 ppm is a difficult and exacting task. The end-to end processing of determining planetary candidates from noisy, raw photometric measurements is discussed.

  1. End-to-end performance measurement of Internet based medical applications.

    PubMed Central

    Dev, P.; Harris, D.; Gutierrez, D.; Shah, A.; Senger, S.

    2002-01-01

    We present a method to obtain an end-to-end characterization of the performance of an application over a network. This method is not dependent on any specific application or type of network. The method requires characterization of network parameters, such as latency and packet loss, between the expected server or client endpoints, as well as characterization of the application's constraints on these parameters. A subjective metric is presented that integrates these characterizations and that operates over a wide range of applications and networks. We believe that this method may be of wide applicability as research and educational applications increasingly make use of computation and data servers that are distributed over the Internet. PMID:12463816

  2. Development of a Dynamic, End-to-End Free Piston Stirling Convertor Model

    NASA Technical Reports Server (NTRS)

    Regan, Timothy F.; Gerber, Scott S.; Roth, Mary Ellen

    2004-01-01

    A dynamic model for a free-piston Stirling convertor is being developed at the NASA Glenn Research Center. The model is an end-to-end system model that includes the cycle thermodynamics, the dynamics, and electrical aspects of the system. The subsystems of interest are the heat source, the springs, the moving masses, the linear alternator, the controller, and the end-user load. The envisioned use of the model will be in evaluating how changes in a subsystem could affect the operation of the convertor. The model under development will speed the evaluation of improvements to a subsystem and aid in determining areas in which most significant improvements may be found. One of the first uses of the end-toend model will be in the development of controller architectures. Another related area is in evaluating changes to details in the linear alternator.

  3. End-to-End QoS for Differentiated Services and ATM Internetworking

    NASA Technical Reports Server (NTRS)

    Su, Hongjun; Atiquzzaman, Mohammed

    2001-01-01

    The Internet was initially design for non real-time data communications and hence does not provide any Quality of Service (QoS). The next generation Internet will be characterized by high speed and QoS guarantee. The aim of this paper is to develop a prioritized early packet discard (PEPD) scheme for ATM switches to provide service differentiation and QoS guarantee to end applications running over next generation Internet. The proposed PEPD scheme differs from previous schemes by taking into account the priority of packets generated from different application. We develop a Markov chain model for the proposed scheme and verify the model with simulation. Numerical results show that the results from the model and computer simulation are in close agreement. Our PEPD scheme provides service differentiation to the end-to-end applications.

  4. The End-to-End Pipeline for HST Slitless Spectra PHLAG

    NASA Astrophysics Data System (ADS)

    Kümmel, M.; Albrecht, R.; Fosbury, R.; Freudling, W.; Haase, J.; Hook, R. N.; Kuntschner, H.; Micol, A.; Rosa, M. R.; Walsh, J. R.

    The Space Telescope-European Coordinating Facility (ST-ECF) is undertaking a joint project with the Canadian Astronomy Data Centre and the Space Telescope Science Institute to build a Hubble Legacy Archive (HLA) that contains science ready high level data products to be used in the Virtual Observatory (VO). The ST-ECF will provide extracted slitless spectra to the HLA, and for this purpose has developed the Pipeline for Hubble Legacy Archive Grism data (PHLAG). PHLAG is an end-to-end pipeline that performs an unsupervised reduction of slitless data taken with the Advanced Camera for Surveys (ACS) or the Near Infrared Camera and Multi Object Spectrometer (NICMOS) and ingests the VO compatible spectra into the HLA. PHLAG is a modular pipeline, and the various modules and their roles are discussed. In a pilot study, PHLAG is applied to NICMOS data taken with the G141 grism, and the first results of a run on all available data are shown.

  5. Orion MPCV GN and C End-to-End Phasing Tests

    NASA Technical Reports Server (NTRS)

    Neumann, Brian C.

    2013-01-01

    End-to-end integration tests are critical risk reduction efforts for any complex vehicle. Phasing tests are an end-to-end integrated test that validates system directional phasing (polarity) from sensor measurement through software algorithms to end effector response. Phasing tests are typically performed on a fully integrated and assembled flight vehicle where sensors are stimulated by moving the vehicle and the effectors are observed for proper polarity. Orion Multi-Purpose Crew Vehicle (MPCV) Pad Abort 1 (PA-1) Phasing Test was conducted from inertial measurement to Launch Abort System (LAS). Orion Exploration Flight Test 1 (EFT-1) has two end-to-end phasing tests planned. The first test from inertial measurement to Crew Module (CM) reaction control system thrusters uses navigation and flight control system software algorithms to process commands. The second test from inertial measurement to CM S-Band Phased Array Antenna (PAA) uses navigation and communication system software algorithms to process commands. Future Orion flights include Ascent Abort Flight Test 2 (AA-2) and Exploration Mission 1 (EM-1). These flights will include additional or updated sensors, software algorithms and effectors. This paper will explore the implementation of end-to-end phasing tests on a flight vehicle which has many constraints, trade-offs and compromises. Orion PA-1 Phasing Test was conducted at White Sands Missile Range (WSMR) from March 4-6, 2010. This test decreased the risk of mission failure by demonstrating proper flight control system polarity. Demonstration was achieved by stimulating the primary navigation sensor, processing sensor data to commands and viewing propulsion response. PA-1 primary navigation sensor was a Space Integrated Inertial Navigation System (INS) and Global Positioning System (GPS) (SIGI) which has onboard processing, INS (3 accelerometers and 3 rate gyros) and no GPS receiver. SIGI data was processed by GN&C software into thrust magnitude and

  6. The Consolidation of the End-to-End Avionics Systems Testbench

    NASA Astrophysics Data System (ADS)

    Wijnands, Quirien; Torelli, Felice; Blommestijn, Robert; Kranz, Stephan; Koster, Jean-Paul

    2014-08-01

    Over the past years, the Avionics System Test Bench (ATB) has been used to support the demonstration and validation of upcoming space avionics related standards and technologies in a representative environment. Next to this another main use-case of the facility has been to support projects in their needs of assessing particular technology related issues. In doing so, it was necessary to add activity- and project specifics to different configurations of the ATB, leading to a proliferation of facilities and technologies. In some cases however the results and lessons-learned from these efforts and activities were considered valuable to the ATB-concept in general and therefore needed preservation in the ATB mainstream for future reuse. Currently activities are ongoing to consolidate the End-To-End Avionics Systems TestBench (E2E-ATB). In this paper the resulting details of these activities are described as enhancements and improvements per ATB configuration.

  7. Enhancing End-to-End Performance of Information Services Over Ka-Band Global Satellite Networks

    NASA Technical Reports Server (NTRS)

    Bhasin, Kul B.; Glover, Daniel R.; Ivancic, William D.; vonDeak, Thomas C.

    1997-01-01

    The Internet has been growing at a rapid rate as the key medium to provide information services such as e-mail, WWW and multimedia etc., however its global reach is limited. Ka-band communication satellite networks are being developed to increase the accessibility of information services via the Internet at global scale. There is need to assess satellite networks in their ability to provide these services and interconnect seamlessly with existing and proposed terrestrial telecommunication networks. In this paper the significant issues and requirements in providing end-to-end high performance for the delivery of information services over satellite networks based on various layers in the OSI reference model are identified. Key experiments have been performed to evaluate the performance of digital video and Internet over satellite-like testbeds. The results of the early developments in ATM and TCP protocols over satellite networks are summarized.

  8. End-to-end communication test on variable length packet structures utilizing AOS testbed

    NASA Technical Reports Server (NTRS)

    Miller, Warner H.; Sank, V.; Fong, Wai; Miko, J.; Powers, M.; Folk, John; Conaway, B.; Michael, K.; Yeh, Pen-Shu

    1994-01-01

    This paper describes a communication test, which successfully demonstrated the transfer of losslessly compressed images in an end-to-end system. These compressed images were first formatted into variable length Consultative Committee for Space Data Systems (CCSDS) packets in the Advanced Orbiting System Testbed (AOST). The CCSDS data Structures were transferred from the AOST to the Radio Frequency Simulations Operations Center (RFSOC), via a fiber optic link, where data was then transmitted through the Tracking and Data Relay Satellite System (TDRSS). The received data acquired at the White Sands Complex (WSC) was transferred back to the AOST where the data was captured and decompressed back to the original images. This paper describes the compression algorithm, the AOST configuration, key flight components, data formats, and the communication link characteristics and test results.

  9. End-to-end automated microfluidic platform for synthetic biology: from design to functional analysis

    DOE PAGESBeta

    Linshiz, Gregory; Jensen, Erik; Stawski, Nina; Bi, Changhao; Elsbree, Nick; Jiao, Hong; Kim, Jungkyu; Mathies, Richard; Keasling, Jay D.; Hillson, Nathan J.

    2016-02-02

    Synthetic biology aims to engineer biological systems for desired behaviors. The construction of these systems can be complex, often requiring genetic reprogramming, extensive de novo DNA synthesis, and functional screening. Here, we present a programmable, multipurpose microfluidic platform and associated software and apply the platform to major steps of the synthetic biology research cycle: design, construction, testing, and analysis. We show the platform’s capabilities for multiple automated DNA assembly methods, including a new method for Isothermal Hierarchical DNA Construction, and for Escherichia coli and Saccharomyces cerevisiae transformation. The platform enables the automated control of cellular growth, gene expression induction, andmore » proteogenic and metabolic output analysis. Finally, taken together, we demonstrate the microfluidic platform’s potential to provide end-to-end solutions for synthetic biology research, from design to functional analysis.« less

  10. Advances in POST2 End-to-End Descent and Landing Simulation for the ALHAT Project

    NASA Technical Reports Server (NTRS)

    Davis, Jody L.; Striepe, Scott A.; Maddock, Robert W.; Hines, Glenn D.; Paschall, Stephen, II; Cohanim, Babak E.; Fill, Thomas; Johnson, Michael C.; Bishop, Robert H.; DeMars, Kyle J.; Sostaric, Ronald r.; Johnson, Andrew E.

    2008-01-01

    Program to Optimize Simulated Trajectories II (POST2) is used as a basis for an end-to-end descent and landing trajectory simulation that is essential in determining design and integration capability and system performance of the lunar descent and landing system and environment models for the Autonomous Landing and Hazard Avoidance Technology (ALHAT) project. The POST2 simulation provides a six degree-of-freedom capability necessary to test, design and operate a descent and landing system for successful lunar landing. This paper presents advances in the development and model-implementation of the POST2 simulation, as well as preliminary system performance analysis, used for the testing and evaluation of ALHAT project system models.

  11. Kinetics of end-to-end collision in short single-stranded nucleic acids.

    PubMed

    Wang, Xiaojuan; Nau, Werner M

    2004-01-28

    A novel fluorescence-based method, which entails contact quenching of the long-lived fluorescent state of 2,3-diazabicyclo[2.2.2]-oct-2-ene (DBO), was employed to measure the kinetics of end-to-end collision in short single-stranded oligodeoxyribonucleotides of the type 5'-DBO-(X)n-dG with X = dA, dC, dT, or dU and n = 2 or 4. The fluorophore was covalently attached to the 5' end and dG was introduced as an efficient intrinsic quencher at the 3' terminus. The end-to-end collision rates, which can be directly related to the efficiency of intramolecular fluorescence quenching, ranged from 0.1 to 9.0 x 10(6) s(-1). They were strongly dependent on the strand length, the base sequence, as well as the temperature. Oligonucleotides containing dA in the backbone displayed much slower collision rates and significantly higher positive activation energies than strands composed of pyrimidine bases, suggesting a higher intrinsic rigidity of oligoadenylate. Comparison of the measured collision rates in short single-stranded oligodeoxyribonucleotides with the previously reported kinetics of hairpin formation indicates that the intramolecular collision is significantly faster than the nucleation step of hairpin closing. This is consistent with the configurational diffusion model suggested by Ansari et al. (Ansari, A.; Kuznetsov, S. V.; Shen, Y. Proc.Natl. Acad. Sci. USA 2001, 98, 7771-7776), in which the formation of misfolded loops is thought to slow hairpin formation. PMID:14733555

  12. Integrating end-to-end threads of control into object-oriented analysis and design

    NASA Technical Reports Server (NTRS)

    Mccandlish, Janet E.; Macdonald, James R.; Graves, Sara J.

    1993-01-01

    Current object-oriented analysis and design methodologies fall short in their use of mechanisms for identifying threads of control for the system being developed. The scenarios which typically describe a system are more global than looking at the individual objects and representing their behavior. Unlike conventional methodologies that use data flow and process-dependency diagrams, object-oriented methodologies do not provide a model for representing these global threads end-to-end. Tracing through threads of control is key to ensuring that a system is complete and timing constraints are addressed. The existence of multiple threads of control in a system necessitates a partitioning of the system into processes. This paper describes the application and representation of end-to-end threads of control to the object-oriented analysis and design process using object-oriented constructs. The issue of representation is viewed as a grouping problem, that is, how to group classes/objects at a higher level of abstraction so that the system may be viewed as a whole with both classes/objects and their associated dynamic behavior. Existing object-oriented development methodology techniques are extended by adding design-level constructs termed logical composite classes and process composite classes. Logical composite classes are design-level classes which group classes/objects both logically and by thread of control information. Process composite classes further refine the logical composite class groupings by using process partitioning criteria to produce optimum concurrent execution results. The goal of these design-level constructs is to ultimately provide the basis for a mechanism that can support the creation of process composite classes in an automated way. Using an automated mechanism makes it easier to partition a system into concurrently executing elements that can be run in parallel on multiple processors.

  13. Development and evaluation of an end-to-end test for head and neck IMRT with a novel multiple-dosimetric modality phantom.

    PubMed

    Zakjevskii, Viatcheslav V; Knill, Cory S; Rakowski, Joseph T; Snyder, Michael G

    2016-01-01

    A comprehensive end-to-end test for head and neck IMRT treatments was developed using a custom phantom designed to utilize multiple dosimetry devices. Initial end-to-end test and custom H&N phantom were designed to yield maximum informa-tion in anatomical regions significant to H&N plans with respect to: (i) geometric accuracy, (ii) dosimetric accuracy, and (iii) treatment reproducibility. The phantom was designed in collaboration with Integrated Medical Technologies. The phantom was imaged on a CT simulator and the CT was reconstructed with 1 mm slice thick-ness and imported into Varian's Eclipse treatment planning system. OARs and the PTV were contoured with the aid of Smart Segmentation. A clinical template was used to create an eight-field IMRT plan and dose was calculated with heterogeneity correction on. Plans were delivered with a TrueBeam equipped with a high definition MLC. Preliminary end-to-end results were measured using film, ion chambers, and optically stimulated luminescent dosimeters (OSLDs). Ion chamber dose measure-ments were compared to the treatment planning system. Films were analyzed with FilmQA Pro using composite gamma index. OSLDs were read with a MicroStar reader using a custom calibration curve. Final phantom design incorporated two axial and one coronal film planes with 18 OSLD locations adjacent to those planes as well as four locations for IMRT ionization chambers below inferior film plane. The end-to-end test was consistently reproducible, resulting in average gamma pass rate greater than 99% using 3%/3 mm analysis criteria, and average OSLD and ion chamber measurements within 1% of planned dose. After initial calibration of OSLD and film systems, the end-to-end test provides next-day results, allowing for integration in routine clinical QA. Preliminary trials have demonstrated that our end-to-end is a reproducible QA tool that enables the ongoing evaluation of dosimetric and geometric accuracy of clinical head and neck treatments

  14. End-to-end test of spatial accuracy in Gamma Knife treatments for trigeminal neuralgia

    SciTech Connect

    Brezovich, Ivan A. Wu, Xingen; Duan, Jun; Popple, Richard A.; Shen, Sui; Benhabib, Sidi; Huang, Mi; Christian Dobelbower, M.; Fisher III, Winfield S.

    2014-11-01

    Purpose: Spatial accuracy is most crucial when small targets like the trigeminal nerve are treated. Although current quality assurance procedures typically verify that individual apparatus, like the MRI scanner, CT scanner, Gamma Knife, etc., are meeting specifications, the cumulative error of all equipment and procedures combined may exceed safe margins. This study uses an end-to-end approach to assess the overall targeting errors that may have occurred in individual patients previously treated for trigeminal neuralgia. Methods: The trigeminal nerve is simulated by a 3 mm long, 3.175 mm (1/8 in.) diameter MRI-contrast filled cavity embedded within a PMMA plastic capsule. The capsule is positioned within the head frame such that the location of the cavity matches the Gamma Knife coordinates of an arbitrarily chosen, previously treated patient. Gafchromic EBT2 film is placed at the center of the cavity in coronal and sagittal orientations. The films are marked with a pinprick to identify the cavity center. Treatments are planned for radiation delivery with 4 mm collimators according to MRI and CT scans using the clinical localizer boxes and acquisition protocols. Shots are planned so that the 50% isodose surface encompasses the cavity. Following irradiation, the films are scanned and analyzed. Targeting errors are defined as the distance between the pinprick, which represents the intended target, and the centroid of the 50% isodose line, which is the center of the radiation field that was actually delivered. Results: Averaged over ten patient simulations, targeting errors along the x, y, and z coordinates (patient’s left-to-right, posterior-to-anterior, and head-to-foot) were, respectively, −0.060 ± 0.363, −0.350 ± 0.253, and 0.348 ± 0.204 mm when MRI was used for treatment planning. Planning according to CT exhibited generally smaller errors, namely, 0.109 ± 0.167, −0.191 ± 0.144, and 0.211 ± 0.094 mm. The largest errors along individual axes in MRI

  15. Mapping Water Vapor Bands using AIRS Measurements for NPOESS/NPP VIIRS Pre-launch End-to-End Testing

    NASA Astrophysics Data System (ADS)

    Qu, J. J.; Hao, X.; Hauss, B.; Wang, C.; Xiong, J.

    2005-12-01

    NPOESS/NPP pre-launch end to end testing is very important for establishing the long-term high quality Environmental Data Records (EDRs). In our early studies, we have developed spatial and spectral mapping technology and demonstrated the AIRS-MODIS-VIIRS band mapping approaches successfully. In this paper, we will focus on VIIRS water vapor band mapping for proxy dataset generating based on our recently established proxy database which includes the AIRS simulated MODIS, AIRS simulated VIIRS and aggregated MODIS radiances/ brightness temperatures. We demonstrate the efficacy of this approach by presenting results of the cross-comparison of water vapor band measurements from AIRS, MODIS and simulated VIIRS. We also investigate the dependence of the quality of water vapor band mapping as a function of the surface emissivity spectrum, phenomenology, and atmospheric conditions. The same approach can be used to map CrIS to VIIRS for post-launch calibration and validation. It is also valuable to keep the continuity between MODIS and VIIRS water vapor measurements. This approach can provide increased confidence in evaluating EDR retrieval algorithms performances. It also can be used to map 6.75 μm band using AIRS or CrIS measurements for water vapor algorithm testing.

  16. Towards end-to-end models for investigating the effects of climate and fishing in marine ecosystems

    NASA Astrophysics Data System (ADS)

    Travers, M.; Shin, Y.-J.; Jennings, S.; Cury, P.

    2007-12-01

    End-to-end models that represent ecosystem components from primary producers to top predators, linked through trophic interactions and affected by the abiotic environment, are expected to provide valuable tools for assessing the effects of climate change and fishing on ecosystem dynamics. Here, we review the main process-based approaches used for marine ecosystem modelling, focusing on the extent of the food web modelled, the forcing factors considered, the trophic processes represented, as well as the potential use and further development of the models. We consider models of a subset of the food web, models which represent the first attempts to couple low and high trophic levels, integrated models of the whole ecosystem, and size spectrum models. Comparisons within and among these groups of models highlight the preferential use of functional groups at low trophic levels and species at higher trophic levels and the different ways in which the models account for abiotic processes. The model comparisons also highlight the importance of choosing an appropriate spatial dimension for representing organism dynamics. Many of the reviewed models could be extended by adding components and by ensuring that the full life cycles of species components are represented, but end-to-end models should provide full coverage of ecosystem components, the integration of physical and biological processes at different scales and two-way interactions between ecosystem components. We suggest that this is best achieved by coupling models, but there are very few existing cases where the coupling supports true two-way interaction. The advantages of coupling models are that the extent of discretization and representation can be targeted to the part of the food web being considered, making their development time- and cost-effective. Processes such as predation can be coupled to allow the propagation of forcing factors effects up and down the food web. However, there needs to be a stronger focus

  17. End-to-end simulation of bunch merging for a muon collider

    SciTech Connect

    Bao, Yu; Stratakis, Diktys; Hanson, Gail G.; Palmer, Robert B.

    2015-05-03

    Muon accelerator beams are commonly produced indirectly through pion decay by interaction of a charged particle beam with a target. Efficient muon capture requires the muons to be first phase-rotated by rf cavities into a train of 21 bunches with much reduced energy spread. Since luminosity is proportional to the square of the number of muons per bunch, it is crucial for a Muon Collider to use relatively few bunches with many muons per bunch. In this paper we will describe a bunch merging scheme that should achieve this goal. We present for the first time a complete end-to-end simulation of a 6D bunch merger for a Muon Collider. The 21 bunches arising from the phase-rotator, after some initial cooling, are merged in longitudinal phase space into seven bunches, which then go through seven paths with different lengths and reach the final collecting "funnel" at the same time. The final single bunch has a transverse and a longitudinal emittance that matches well with the subsequent 6D rectilinear cooling scheme.

  18. End-To-End performance test of the LINC-NIRVANA Wavefront-Sensor system.

    NASA Astrophysics Data System (ADS)

    Berwein, Juergen; Bertram, Thomas; Conrad, Al; Briegel, Florian; Kittmann, Frank; Zhang, Xiangyu; Mohr, Lars

    2011-09-01

    LINC-NIRVANA is an imaging Fizeau interferometer, for use in near infrared wavelengths, being built for the Large Binocular Telescope. Multi-conjugate adaptive optics (MCAO) increases the sky coverage and the field of view over which diffraction limited images can be obtained. For its MCAO implementation, Linc-Nirvana utilizes four total wavefront sensors; each of the two beams is corrected by both a ground-layer wavefront sensor (GWS) and a high-layer wavefront sensor (HWS). The GWS controls the adaptive secondary deformable mirror (DM), which is based on an DSP slope computing unit. Whereas the HWS controls an internal DM via computations provided by an off-the-shelf multi-core Linux system. Using wavefront sensor data collected from a prior lab experiment, we have shown via simulation that the Linux based system is sufficient to operate at 1kHz, with jitter well below the needs of the final system. Based on that setup we tested the end-to-end performance and latency through all parts of the system which includes the camera, the wavefront controller, and the deformable mirror. We will present our loop control structure and the results of those performance tests.

  19. End to End Digitisation and Analysis of Three-Dimensional Coral Models, from Communities to Corallites.

    PubMed

    Gutierrez-Heredia, Luis; Benzoni, Francesca; Murphy, Emma; Reynaud, Emmanuel G

    2016-01-01

    Coral reefs hosts nearly 25% of all marine species and provide food sources for half a billion people worldwide while only a very small percentage have been surveyed. Advances in technology and processing along with affordable underwater cameras and Internet availability gives us the possibility to provide tools and softwares to survey entire coral reefs. Holistic ecological analyses of corals require not only the community view (10s to 100s of meters), but also the single colony analysis as well as corallite identification. As corals are three-dimensional, classical approaches to determine percent cover and structural complexity across spatial scales are inefficient, time-consuming and limited to experts. Here we propose an end-to-end approach to estimate these parameters using low-cost equipment (GoPro, Canon) and freeware (123D Catch, Meshmixer and Netfabb), allowing every community to participate in surveys and monitoring of their coral ecosystem. We demonstrate our approach on 9 species of underwater colonies in ranging size and morphology. 3D models of underwater colonies, fresh samples and bleached skeletons with high quality texture mapping and detailed topographic morphology were produced, and Surface Area and Volume measurements (parameters widely used for ecological and coral health studies) were calculated and analysed. Moreover, we integrated collected sample models with micro-photogrammetry models of individual corallites to aid identification and colony and polyp scale analysis. PMID:26901845

  20. Availability and End-to-end Reliability in Low Duty Cycle Multihop Wireless Sensor Networks.

    PubMed

    Suhonen, Jukka; Hämäläinen, Timo D; Hännikäinen, Marko

    2009-01-01

    A wireless sensor network (WSN) is an ad-hoc technology that may even consist of thousands of nodes, which necessitates autonomic, self-organizing and multihop operations. A typical WSN node is battery powered, which makes the network lifetime the primary concern. The highest energy efficiency is achieved with low duty cycle operation, however, this alone is not enough. WSNs are deployed for different uses, each requiring acceptable Quality of Service (QoS). Due to the unique characteristics of WSNs, such as dynamic wireless multihop routing and resource constraints, the legacy QoS metrics are not feasible as such. We give a new definition to measure and implement QoS in low duty cycle WSNs, namely availability and reliability. Then, we analyze the effect of duty cycling for reaching the availability and reliability. The results are obtained by simulations with ZigBee and proprietary TUTWSN protocols. Based on the results, we also propose a data forwarding algorithm suitable for resource constrained WSNs that guarantees end-to-end reliability while adding a small overhead that is relative to the packet error rate (PER). The forwarding algorithm guarantees reliability up to 30% PER. PMID:22574002

  1. SPOKES: An end-to-end simulation facility for spectroscopic cosmological surveys

    NASA Astrophysics Data System (ADS)

    Nord, B.; Amara, A.; Réfrégier, A.; Gamper, La.; Gamper, Lu.; Hambrecht, B.; Chang, C.; Forero-Romero, J. E.; Serrano, S.; Cunha, C.; Coles, O.; Nicola, A.; Busha, M.; Bauer, A.; Saunders, W.; Jouvel, S.; Kirk, D.; Wechsler, R.

    2016-04-01

    The nature of dark matter, dark energy and large-scale gravity pose some of the most pressing questions in cosmology today. These fundamental questions require highly precise measurements, and a number of wide-field spectroscopic survey instruments are being designed to meet this requirement. A key component in these experiments is the development of a simulation tool to forecast science performance, define requirement flow-downs, optimize implementation, demonstrate feasibility, and prepare for exploitation. We present SPOKES (SPectrOscopic KEn Simulation), an end-to-end simulation facility for spectroscopic cosmological surveys designed to address this challenge. SPOKES is based on an integrated infrastructure, modular function organization, coherent data handling and fast data access. These key features allow reproducibility of pipeline runs, enable ease of use and provide flexibility to update functions within the pipeline. The cyclic nature of the pipeline offers the possibility to make the science output an efficient measure for design optimization and feasibility testing. We present the architecture, first science, and computational performance results of the simulation pipeline. The framework is general, but for the benchmark tests, we use the Dark Energy Spectrometer (DESpec), one of the early concepts for the upcoming project, the Dark Energy Spectroscopic Instrument (DESI). We discuss how the SPOKES framework enables a rigorous process to optimize and exploit spectroscopic survey experiments in order to derive high-precision cosmological measurements optimally.

  2. End-to-end performance modeling of passive remote sensing systems

    SciTech Connect

    Smith, B.W.; Borel, C.C.; Clodius, W.B.; Theiler, J.; Laubscher, B.; Weber, P.G.

    1996-07-01

    The ultimate goal of end-to-end system modeling is to simulate all known physical effects which determine the content of the data, before flying an instrument system. In remote sensing, one begins with a scene, viewed either statistically or dynamically, computes the radiance in each spectral band, renders the scene, transfers it through representative atmospheres to create the radiance field at an aperture, and integrates over sensor pixels. We have simulated a comprehensive sequence of realistic instrument hardware elements and the transfer of simulated data to an analysis system. This analysis package is the same as that intended for use of data collections from the real system. By comparing the analyzed image to the original scene, the net effect of nonideal system components can be understood. Iteration yields the optimum values of system parameters to achieve performance targets. We have used simulation to develop and test improved multispectral algorithms for (1) the robust retrieval of water surface temperature, water vapor column, and other quantities; (2) the preservation of radiometric accuracy during atmospheric correction and pixel registration on the ground; and (3) exploitation of on-board multispectral measurements to assess the atmosphere between ground and aperture.

  3. End-To-End Simulation of Launch Vehicle Trajectories Including Stage Separation Dynamics

    NASA Technical Reports Server (NTRS)

    Albertson, Cindy W.; Tartabini, Paul V.; Pamadi, Bandu N.

    2012-01-01

    The development of methodologies, techniques, and tools for analysis and simulation of stage separation dynamics is critically needed for successful design and operation of multistage reusable launch vehicles. As a part of this activity, the Constraint Force Equation (CFE) methodology was developed and implemented in the Program to Optimize Simulated Trajectories II (POST2). The objective of this paper is to demonstrate the capability of POST2/CFE to simulate a complete end-to-end mission. The vehicle configuration selected was the Two-Stage-To-Orbit (TSTO) Langley Glide Back Booster (LGBB) bimese configuration, an in-house concept consisting of a reusable booster and an orbiter having identical outer mold lines. The proximity and isolated aerodynamic databases used for the simulation were assembled using wind-tunnel test data for this vehicle. POST2/CFE simulation results are presented for the entire mission, from lift-off, through stage separation, orbiter ascent to orbit, and booster glide back to the launch site. Additionally, POST2/CFE stage separation simulation results are compared with results from industry standard commercial software used for solving dynamics problems involving multiple bodies connected by joints.

  4. Availability and End-to-end Reliability in Low Duty Cycle Multihop Wireless Sensor Networks

    PubMed Central

    Suhonen, Jukka; Hämäläinen, Timo D.; Hännikäinen, Marko

    2009-01-01

    A wireless sensor network (WSN) is an ad-hoc technology that may even consist of thousands of nodes, which necessitates autonomic, self-organizing and multihop operations. A typical WSN node is battery powered, which makes the network lifetime the primary concern. The highest energy efficiency is achieved with low duty cycle operation, however, this alone is not enough. WSNs are deployed for different uses, each requiring acceptable Quality of Service (QoS). Due to the unique characteristics of WSNs, such as dynamic wireless multihop routing and resource constraints, the legacy QoS metrics are not feasible as such. We give a new definition to measure and implement QoS in low duty cycle WSNs, namely availability and reliability. Then, we analyze the effect of duty cycling for reaching the availability and reliability. The results are obtained by simulations with ZigBee and proprietary TUTWSN protocols. Based on the results, we also propose a data forwarding algorithm suitable for resource constrained WSNs that guarantees end-to-end reliability while adding a small overhead that is relative to the packet error rate (PER). The forwarding algorithm guarantees reliability up to 30% PER. PMID:22574002

  5. End-to-end flood risk assessment: A coupled model cascade with uncertainty estimation

    NASA Astrophysics Data System (ADS)

    McMillan, Hilary K.; Brasington, James

    2008-03-01

    This paper presents the case for an `End-to-End' flood inundation modeling strategy: the creation of a coupled system of models to allow continuous simulation methodology to be used to predict the magnitude and simulate the effects of high return period flood events. The framework brings together the best in current thinking on reduced complexity modeling to formulate an efficient, process-based methodology which meets the needs of today's flood mitigation strategies. The model chain is subject to stochasticity and parameter uncertainty, and integral methods to allow the propagation and quantification of uncertainty are essential in order to produce robust estimates of flood risk. Results from an experimental application are considered in terms of their implications for successful floodplain management, and compared against the deterministic methodology more commonly in use for flood risk assessment applications. The provenance of predictive uncertainty is also considered in order to identify those areas where future effort in terms of data collection or model refinement might best be directed in order to narrow prediction bounds and produce a more precise forecast.

  6. Telecommunications end-to-end systems monitoring on TOPEX/Poseidon: Tools and techniques

    NASA Technical Reports Server (NTRS)

    Calanche, Bruno J.

    1994-01-01

    The TOPEX/Poseidon Project Satellite Performance Analysis Team's (SPAT) roles and responsibilities have grown to include functions that are typically performed by other teams on JPL Flight Projects. In particular, SPAT Telecommunication's role has expanded beyond the nominal function of monitoring, assessing, characterizing, and trending the spacecraft (S/C) RF/Telecom subsystem to one of End-to-End Information Systems (EEIS) monitoring. This has been accomplished by taking advantage of the spacecraft and ground data system structures and protocols. By processing both the received spacecraft telemetry minor frame ground generated CRC flags and NASCOM block poly error flags, bit error rates (BER) for each link segment can be determined. This provides the capability to characterize the separate link segments, determine science data recovery, and perform fault/anomaly detection and isolation. By monitoring and managing the links, TOPEX has successfully recovered approximately 99.9 percent of the science data with an integrity (BER) of better than 1 x 10(exp 8). This paper presents the algorithms used to process the above flags and the techniques used for EEIS monitoring.

  7. Telemetry Ranging: Laboratory Validation Tests and End-to-End Performance

    NASA Astrophysics Data System (ADS)

    Hamkins, J.; Kinman, P.; Xie, H.; Vilnrotter, V.; Dolinar, S.; Adams, N.; Sanchez, E.; Millard, W.

    2016-08-01

    This article reports on a set of laboratory tests of telemetry ranging conducted at Development Test Facility 21 (DTF-21) in Monrovia, California. An uplink pseudorandom noise (PN) ranging signal was generated by DTF-21, acquired by the Frontier Radio designed and built at the Johns Hopkins University Applied Physics Laboratory, and downlink telemetry frames from the radio were recorded by an open-loop receiver. In four of the tests, the data indicate that telemetry ranging can resolve the two-way time delay to a standard deviation of 2.1-3.4 ns, corresponding to about 30 to 51 cm in (one-way) range accuracy, when 30 s averaging of timing estimates is used. Other tests performed worse because of unsatisfactory receiver sampling rate, quantizer resolution, dc bias, improper configuration, or other reasons. The article also presents an analysis of the expected end-to-end performance of the telemetry ranging system. In one case considered, the theoretically-predicted performance matches the test results, within 10 percent, which provides a reasonable validation that the expected performance was achieved by the test. The analysis also shows that in one typical ranging scenario, one-way range accuracy of 1 m can be achieved with telemetry ranging when the data rate is above 2 kbps.

  8. Functional Partitioning to Optimize End-to-End Performance on Many-core Architectures

    SciTech Connect

    Li, Min; Vazhkudai, Sudharshan S; Butt, Ali R; Meng, Fei; Ma, Xiaosong; Kim, Youngjae; Engelmann, Christian; Shipman, Galen M

    2010-01-01

    Scaling computations on emerging massive-core supercomputers is a daunting task, which coupled with the significantly lagging system I/O capabilities exacerbates applications end-to-end performance. The I/O bottleneck often negates potential performance benefits of assigning additional compute cores to an application. In this paper, we address this issue via a novel functional partitioning (FP) runtime environment that allocates cores to specific application tasks - checkpointing, de-duplication, and scientific data format transformation - so that the deluge of cores can be brought to bear on the entire gamut of application activities. The focus is on utilizing the extra cores to support HPC application I/O activities and also leverage solid-state disks in this context. For example, our evaluation shows that dedicating 1 core on an oct-core machine for checkpointing and its assist tasks using FP can improve overall execution time of a FLASH benchmark on 80 and 160 cores by 43.95% and 41.34%, respectively.

  9. End to End Digitisation and Analysis of Three-Dimensional Coral Models, from Communities to Corallites

    PubMed Central

    Gutierrez-Heredia, Luis; Benzoni, Francesca; Murphy, Emma; Reynaud, Emmanuel G.

    2016-01-01

    Coral reefs hosts nearly 25% of all marine species and provide food sources for half a billion people worldwide while only a very small percentage have been surveyed. Advances in technology and processing along with affordable underwater cameras and Internet availability gives us the possibility to provide tools and softwares to survey entire coral reefs. Holistic ecological analyses of corals require not only the community view (10s to 100s of meters), but also the single colony analysis as well as corallite identification. As corals are three-dimensional, classical approaches to determine percent cover and structural complexity across spatial scales are inefficient, time-consuming and limited to experts. Here we propose an end-to-end approach to estimate these parameters using low-cost equipment (GoPro, Canon) and freeware (123D Catch, Meshmixer and Netfabb), allowing every community to participate in surveys and monitoring of their coral ecosystem. We demonstrate our approach on 9 species of underwater colonies in ranging size and morphology. 3D models of underwater colonies, fresh samples and bleached skeletons with high quality texture mapping and detailed topographic morphology were produced, and Surface Area and Volume measurements (parameters widely used for ecological and coral health studies) were calculated and analysed. Moreover, we integrated collected sample models with micro-photogrammetry models of individual corallites to aid identification and colony and polyp scale analysis. PMID:26901845

  10. The X-IFU end-to-end simulations performed for the TES array optimization exercise

    NASA Astrophysics Data System (ADS)

    Peille, Philippe; Wilms, J.; Brand, T.; Cobo, B.; Ceballos, M. T.; Dauser, T.; Smith, S. J.; Barret, D.; den Herder, J. W.; Piro, L.; Barcons, X.; Pointecouteau, E.; Bandler, S.; den Hartog, R.; de Plaa, J.

    2015-09-01

    The focal plane assembly of the Athena X-ray Integral Field Unit (X-IFU) includes as the baseline an array of ~4000 single size calorimeters based on Transition Edge Sensors (TES). Other sensor array configurations could however be considered, combining TES of different properties (e.g. size). In attempting to improve the X-IFU performance in terms of field of view, count rate performance, and even spectral resolution, two alternative TES array configurations to the baseline have been simulated, each combining a small and a large pixel array. With the X-IFU end-to-end simulator, a sub-sample of the Athena core science goals, selected by the X-IFU science team as potentially driving the optimal TES array configuration, has been simulated for the results to be scientifically assessed and compared. In this contribution, we will describe the simulation set-up for the various array configurations, and highlight some of the results of the test cases simulated.

  11. A Framework for End to End Simulations of the Large Synoptic Survey Telescope

    NASA Astrophysics Data System (ADS)

    Gibson, R. R.; Ahmad, Z.; Bankert, J.; Bard, D.; Connolly, A. J.; Chang, C.; Gilmore, K.; Grace, E.; Hannel, M.; Jernigan, J. G.; Jones, L.; Kahn, S. M.; Krughoff, K. S.; Lorenz, S.; Marshall, S.; Nagarajan, S.; Peterson, J. R.; Pizagno, J.; Rasmussen, A. P.; Shmakova, M.; Silvestri, N.; Todd, N.; Young, M.

    2011-07-01

    As observatories get bigger and more complicated to operate, risk mitigation techniques become increasingly important. Additionally, the size and complexity of data coming from the next generation of surveys will present enormous challenges in how we process, store, and analyze these data. End-to-end simulations of telescopes with the scope of LSST are essential to correct problems and verify science capabilities as early as possible. A simulator can also determine how defects and trade-offs in individual subsystems impact the overall design requirements. Here, we present the architecture, implementation, and results of the source simulation framework for the Large Synoptic Survey Telescope (LSST). The framework creates time-based realizations of astronomical objects and formats the output for use in many different survey contexts (i.e., image simulation, reference catalogs, calibration catalogs, and simulated science outputs). The simulations include Milky Way, cosmological, and solar system models as well as transient and variable objects. All model objects can be sampled with the LSST cadence from any operations simulator run. The result is a representative, full-sky simulation of LSST data that can be used to determine telescope performance, the feasibility of science goals, and strategies for processing LSST-scale data volumes.

  12. Advanced end-to-end fiber optic sensing systems for demanding environments

    NASA Astrophysics Data System (ADS)

    Black, Richard J.; Moslehi, Behzad

    2010-09-01

    Optical fibers are small-in-diameter, light-in-weight, electromagnetic-interference immune, electrically passive, chemically inert, flexible, embeddable into different materials, and distributed-sensing enabling, and can be temperature and radiation tolerant. With appropriate processing and/or packaging, they can be very robust and well suited to demanding environments. In this paper, we review a range of complete end-to-end fiber optic sensor systems that IFOS has developed comprising not only (1) packaged sensors and mechanisms for integration with demanding environments, but (2) ruggedized sensor interrogators, and (3) intelligent decision aid algorithms software systems. We examine the following examples: " Fiber Bragg Grating (FBG) optical sensors systems supporting arrays of environmentally conditioned multiplexed FBG point sensors on single or multiple optical fibers: In conjunction with advanced signal processing, decision aid algorithms and reasoners, FBG sensor based structural health monitoring (SHM) systems are expected to play an increasing role in extending the life and reducing costs of new generations of aerospace systems. Further, FBG based structural state sensing systems have the potential to considerably enhance the performance of dynamic structures interacting with their environment (including jet aircraft, unmanned aerial vehicles (UAVs), and medical or extravehicular space robots). " Raman based distributed temperature sensing systems: The complete length of optical fiber acts as a very long distributed sensor which may be placed down an oil well or wrapped around a cryogenic tank.

  13. A Workflow-based Intelligent Network Data Movement Advisor with End-to-end Performance Optimization

    SciTech Connect

    Zhu, Michelle M.; Wu, Chase Q.

    2013-11-07

    Next-generation eScience applications often generate large amounts of simulation, experimental, or observational data that must be shared and managed by collaborative organizations. Advanced networking technologies and services have been rapidly developed and deployed to facilitate such massive data transfer. However, these technologies and services have not been fully utilized mainly because their use typically requires significant domain knowledge and in many cases application users are even not aware of their existence. By leveraging the functionalities of an existing Network-Aware Data Movement Advisor (NADMA) utility, we propose a new Workflow-based Intelligent Network Data Movement Advisor (WINDMA) with end-to-end performance optimization for this DOE funded project. This WINDMA system integrates three major components: resource discovery, data movement, and status monitoring, and supports the sharing of common data movement workflows through account and database management. This system provides a web interface and interacts with existing data/space management and discovery services such as Storage Resource Management, transport methods such as GridFTP and GlobusOnline, and network resource provisioning brokers such as ION and OSCARS. We demonstrate the efficacy of the proposed transport-support workflow system in several use cases based on its implementation and deployment in DOE wide-area networks.

  14. An end-to-end analysis of drought from smallholder farms in southwest Jamaica

    NASA Astrophysics Data System (ADS)

    Curtis, W. R. S., III; Gamble, D. W.; Popke, J.

    2015-12-01

    Drought can be defined in many ways: meteorological, hydrological, agricultural, and socio-economic. Another way to approach drought is from a "perception" perspective, where individuals whose livelihood is highly dependent on precipitation take adaptive actions. In this study we use two-years of data collected from twelve smallholder farms in southern St. Elizabeth, Jamaica to undertake an end-to-end analysis of drought. At each farm, 6-hour temperature and soil moisture, and tipping-bucket rainfall were recorded from June 2013 to June 2015, and twice-monthly farmers indicated whether they were experiencing drought and if they irrigated (hand-watering, drip irrigation, or pipe and sprinkler). In many cases half of the farmers considered themselves in a drought, while the others not, even though the largest separation among farms was about 20 km. This study will use analysis of variance to test the following hypotheses: Drought perception is related to a) absolute amounts of precipitation at the time, b) other environmental cues at the time (soil moisture, temperature), or c) relative amounts of precipitation as compared to the same time last year. Irrigation actions and water use following the perception of drought will also be examined.

  15. An end-to-end architecture for distributing weather alerts to wireless handsets

    NASA Astrophysics Data System (ADS)

    Jones, Karen L.; Nguyen, Hung

    2005-06-01

    This paper describes the current National Weather Service's (NWS) system for providing weather alerts in the U.S. and will review how the existing end-to-end architecture is being leveraged to provide non-weather alerts, also known as "all-hazard alerts", to the general public. The paper then describes how a legacy system that transmits weather and all-hazard alerts can be extended via commercial wireless networks and protocols to reach 154 million Americans who carry cell phones. This approach uses commercial SATCOM and existing wireless carriers and services such as Short Messaging Service (SMS) for text and emerging Multimedia Messaging Service (MMS) protocol, which would allow for photos, maps, audio and video alerts to be sent to end users. This wireless broadcast alert delivery architecture is designed to be open and to embrace the National Weather Service's mandate to become an "" warning system for the general public. Examples of other public and private sector applications that require timely and intelligent push mechanisms using this alert dissemination approach are also given.

  16. End-to-end differential contactless conductivity sensor for microchip capillary electrophoresis.

    PubMed

    Fercher, Georg; Haller, Anna; Smetana, Walter; Vellekoop, Michael J

    2010-04-15

    In this contribution, a novel measurement approach for miniaturized capillary electrophoresis (CE) devices is presented: End-to-end differential capacitively coupled contactless conductivity measurement. This measurement technique is applied to a miniaturized CE device fabricated in low-temperature cofired ceramics (LTCC) multilayer technology. The working principle is based on the placement of two distinct detector areas near both ends of the fluid inlet and outlet of the separation channel. Both output signals are subtracted from each other, and the resulting differential signal is amplified and measured. This measurement approach has several advantages over established, single-end detectors: The high baseline level resulting from parasitic stray capacitance and buffer conductivity is reduced, leading to better signal-to-noise ratio and hence higher measurement sensitivity. Furthermore, temperature and, thus, baseline drift effects are diminished owing to the differentiating nature of the system. By comparing the peak widths measured with both detectors, valuable information about zone dispersion effects arising during the separation is obtained. Additionally, the novel measurement scheme allows the determination of dispersion effects that occur at the time of sample injection. Optical means of dispersion evaluation are ineffective because of the opaque LTCC substrate. Electrophoretic separation experiments of inorganic ions show sensitivity enhancements by about a factor of 30-60 compared to the single-end measurement scheme. PMID:20337422

  17. Semantic Complex Event Processing over End-to-End Data Flows

    SciTech Connect

    Zhou, Qunzhi; Simmhan, Yogesh; Prasanna, Viktor K.

    2012-04-01

    Emerging Complex Event Processing (CEP) applications in cyber physical systems like SmartPower Grids present novel challenges for end-to-end analysis over events, flowing from heterogeneous information sources to persistent knowledge repositories. CEP for these applications must support two distinctive features - easy specification patterns over diverse information streams, and integrated pattern detection over realtime and historical events. Existing work on CEP has been limited to relational query patterns, and engines that match events arriving after the query has been registered. We propose SCEPter, a semantic complex event processing framework which uniformly processes queries over continuous and archived events. SCEPteris built around an existing CEP engine with innovative support for semantic event pattern specification and allows their seamless detection over past, present and future events. Specifically, we describe a unified semantic query model that can operate over data flowing through event streams to event repositories. Compile-time and runtime semantic patterns are distinguished and addressed separately for efficiency. Query rewriting is examined and analyzed in the context of temporal boundaries that exist between event streams and their repository to avoid duplicate or missing results. The design and prototype implementation of SCEPterare analyzed using latency and throughput metrics for scenarios from the Smart Grid domain.

  18. The efficacy of end-to-end and end-to-side nerve repair (neurorrhaphy) in the rat brachial plexus

    PubMed Central

    Liao, Wen-Chieh; Chen, Jeng-Rung; Wang, Yueh-Jan; Tseng, Guo-Fang

    2009-01-01

    Proximal nerve injury often requires nerve transfer to restore function. Here we evaluated the efficacy of end-to-end and end-to-side neurorrhaphy of rat musculocutaneous nerve, the recipient, to ulnar nerve, the donor. The donor was transected for end-to-end, while an epineurial window was exposed for end-to-side neurorrhaphy. Retrograde tracing showed that 70% donor motor and sensory neurons grew into the recipient 3 months following end-to-end neurorrhaphy compared to 40–50% at 6 months following end-to-side neurorrhaphy. In end-to-end neurorrhaphy, regenerating axons appeared as thick fibers which regained diameters comparable to those of controls in 3–4 months. However, end-to-side neurorrhaphy induced slow sprouting fibers of mostly thin collaterals that barely approached control diameters by 6 months. The motor end plates regained their control density at 4 months following end-to-end but remained low 6 months following end-to-side neurorrhaphy. The short-latency compound muscle action potential, typical of that of control, was readily restored following end-to-end neurorrhaphy. End-to-side neurorrhaphy had low amplitude and wide-ranging latency at 4 months and failed to regain control sizes by 6 months. Grooming test recovered successfully at 3 and 6 months following end-to-end and end-to-side neurorrhaphy, respectively, suggesting that powerful muscle was not required. In short, both neurorrhaphies resulted in functional recovery but end-to-end neurorrhaphy was quicker and better, albeit at the expense of donor function. End-to-side neurorrhaphy supplemented with factors to overcome the slow collateral sprouting and weak motor recovery may warrant further exploration. PMID:19682138

  19. In vivo laser assisted end-to-end anastomosis with ICG-infused chitosan patches

    NASA Astrophysics Data System (ADS)

    Rossi, Francesca; Matteini, Paolo; Esposito, Giuseppe; Scerrati, Alba; Albanese, Alessio; Puca, Alfredo; Maira, Giulio; Rossi, Giacomo; Pini, Roberto

    2011-07-01

    Laser assisted vascular repair is a new optimized technique based on the use of ICG-infused chitosan patch to close a vessel wound, with or even without few supporting single stitches. We present an in vivo experimental study on an innovative end-to-end laser assisted vascular anastomotic (LAVA) technique, performed with the application of ICGinfused chitosan patches. The photostability and the mechanical properties of ICG-infused chitosan films were preliminary measured. The in vivo study was performed in 10 New Zealand rabbits. After anesthesia, a 3-cm segment of the right common carotid artery was exposed, thus clamped proximally and distally. The artery was then interrupted by means of a full thickness cut. Three single microsutures were used to approximate the two vessel edges. The ICG-infused chitosan patch was rolled all over the anastomotic site and welded by the use of a diode laser emitting at 810 nm and equipped with a 300 μm diameter optical fiber. Welding was obtained by delivering single laser spots to induce local patch/tissue adhesion. The result was an immediate closure of the anastomosis, with no bleeding at clamps release. Thus animals underwent different follow-up periods, in order to evaluate the welded vessels over time. At follow-up examinations, all the anastomoses were patent and no bleeding signs were documented. Samples of welded vessels underwent histological examinations. Results showed that this technique offer several advantages over conventional suturing methods: simplification of the surgical procedure, shortening of the operative time, better re-endothelization and optimal vascular healing process.

  20. Advanced End-to-end Simulation for On-board Processing (AESOP)

    NASA Technical Reports Server (NTRS)

    Mazer, Alan S.

    1994-01-01

    Developers of data compression algorithms typically use their own software together with commercial packages to implement, evaluate and demonstrate their work. While convenient for an individual developer, this approach makes it difficult to build on or use another's work without intimate knowledge of each component. When several people or groups work on different parts of the same problem, the larger view can be lost. What's needed is a simple piece of software to stand in the gap and link together the efforts of different people, enabling them to build on each other's work, and providing a base for engineers and scientists to evaluate the parts as a cohesive whole and make design decisions. AESOP (Advanced End-to-end Simulation for On-board Processing) attempts to meet this need by providing a graphical interface to a developer-selected set of algorithms, interfacing with compiled code and standalone programs, as well as procedures written in the IDL and PV-Wave command languages. As a proof of concept, AESOP is outfitted with several data compression algorithms integrating previous work on different processors (AT&T DSP32C, TI TMS320C30, SPARC). The user can specify at run-time the processor on which individual parts of the compression should run. Compressed data is then fed through simulated transmission and uncompression to evaluate the effects of compression parameters, noise and error correction algorithms. The following sections describe AESOP in detail. Section 2 describes fundamental goals for usability. Section 3 describes the implementation. Sections 4 through 5 describe how to add new functionality to the system and present the existing data compression algorithms. Sections 6 and 7 discuss portability and future work.

  1. SME2EM: Smart mobile end-to-end monitoring architecture for life-long diseases.

    PubMed

    Serhani, Mohamed Adel; Menshawy, Mohamed El; Benharref, Abdelghani

    2016-01-01

    Monitoring life-long diseases requires continuous measurements and recording of physical vital signs. Most of these diseases are manifested through unexpected and non-uniform occurrences and behaviors. It is impractical to keep patients in hospitals, health-care institutions, or even at home for long periods of time. Monitoring solutions based on smartphones combined with mobile sensors and wireless communication technologies are a potential candidate to support complete mobility-freedom, not only for patients, but also for physicians. However, existing monitoring architectures based on smartphones and modern communication technologies are not suitable to address some challenging issues, such as intensive and big data, resource constraints, data integration, and context awareness in an integrated framework. This manuscript provides a novel mobile-based end-to-end architecture for live monitoring and visualization of life-long diseases. The proposed architecture provides smartness features to cope with continuous monitoring, data explosion, dynamic adaptation, unlimited mobility, and constrained devices resources. The integration of the architecture׳s components provides information about diseases׳ recurrences as soon as they occur to expedite taking necessary actions, and thus prevent severe consequences. Our architecture system is formally model-checked to automatically verify its correctness against designers׳ desirable properties at design time. Its components are fully implemented as Web services with respect to the SOA architecture to be easy to deploy and integrate, and supported by Cloud infrastructure and services to allow high scalability, availability of processes and data being stored and exchanged. The architecture׳s applicability is evaluated through concrete experimental scenarios on monitoring and visualizing states of epileptic diseases. The obtained theoretical and experimental results are very promising and efficiently satisfy the proposed

  2. End-To-END Performance of the Future MOMA Instrument Aboard the ExoMars Mission

    NASA Astrophysics Data System (ADS)

    Pinnick, V. T.; Buch, A.; Szopa, C.; Grand, N.; Danell, R.; Grubisic, A.; van Amerom, F. H. W.; Glavin, D. P.; Freissinet, C.; Coll, P. J.; Stalport, F.; Humeau, O.; Arevalo, R. D., Jr.; Brinckerhoff, W. B.; Steininger, H.; Goesmann, F.; Raulin, F.; Mahaffy, P. R.

    2015-12-01

    Following the SAM experiment aboard the Curiosity rover, the Mars Organic Molecule Analyzer (MOMA) experiment aboard the 2018 ExoMars mission will be the continuation of the search for organic matter on the Mars surface. One advancement with the ExoMars mission is that the sample will be extracted as deep as 2 meters below the Martian surface to minimize effects of radiation and oxidation on organic materials. To analyze the wide range of organic composition (volatile and non-volatile compounds) of the Martian soil, MOMA is equipped with a dual ion source ion trap mass spectrometer utilizing UV laser desorption / ionization (LDI) and pyrolysis gas chromatography (pyr-GC). In order to analyze refractory organic compounds and chiral molecules during GC-ITMS analysis, samples may be submitted to a derivatization process, consisting of the reaction of the sample components with specific reactants (MTBSTFA [1], DMF-DMA [2] or TMAH [3]). Previous experimental reports have focused on coupling campaigns between the breadboard versions of the GC, provided by the French team (LISA, LATMOS, CentraleSupelec), and the MS, provided by the US team (NASA-GSFC). This work focuses on the performance verification and optimization of the GC-ITMS experiment using the Engineering Test Unit (ETU) models which are representative of the form, fit and function of the flight instrument including a flight-like pyrolysis oven and tapping station providing by the German team (MPS). The results obtained demonstrate the current status of the end-to-end performance of the gas chromatography-mass spectrometry mode of operation. References: [1] Buch, A. et al. (2009) J Chrom. A, 43, 143-151. [2] Freissinet et al. (2011) J Chrom A, 1306, 59-71. [3] Geffroy-Rodier, C. et al. (2009) JAAP, 85, 454-459.

  3. SPoRT - An End-to-End R2O Activity

    NASA Technical Reports Server (NTRS)

    Jedlovec, Gary J.

    2009-01-01

    Established in 2002 to demonstrate the weather and forecasting application of real-time EOS measurements, the Short-term Prediction Research and Transition (SPoRT) program has grown to be an end-to-end research to operations activity focused on the use of advanced NASA modeling and data assimilation approaches, nowcasting techniques, and unique high-resolution multispectral observational data applications from EOS satellites to improve short-term weather forecasts on a regional and local scale. SPoRT currently partners with several universities and other government agencies for access to real-time data and products, and works collaboratively with them and operational end users at 13 WFOs to develop and test the new products and capabilities in a "test-bed" mode. The test-bed simulates key aspects of the operational environment without putting constraints on the forecaster workload. Products and capabilities which show utility in the test-bed environment are then transitioned experimentally into the operational environment for further evaluation and assessment. SPoRT focuses on a suite of data and products from MODIS, AMSR-E, and AIRS on the NASA Terra and Aqua satellites, and total lightning measurements from ground-based networks. Some of the observations are assimilated into or used with various versions of the WRF model to provide supplemental forecast guidance to operational end users. SPoRT is enhancing partnerships with NOAA / NESDIS for new product development and data access to exploit the remote sensing capabilities of instruments on the NPOESS satellites to address short term weather forecasting problems. The VIIRS and CrIS instruments on the NPP and follow-on NPOESS satellites provide similar observing capabilities to the MODIS and AIRS instruments on Terra and Aqua. SPoRT will be transitioning existing and new capabilities into the AWIIPS II environment to continue the continuity of its activities.

  4. Implementation and evaluation of an end-to-end IGRT test.

    PubMed

    Kry, Stephen F; Jones, Jimmy; Childress, Nathan L

    2012-01-01

    The goal of this work was to develop and evaluate an end-to-end test for determining and verifying image-guided radiation therapy setup accuracy relative to the radiation isocenter. This was done by placing a cube phantom with a central tungsten sphere directly on the treatment table and offset from isocenter either by 5.0 mm in the longitudinal, lateral, and vertical dimensions or by a random amount. A high-resolution cone-beam CT image was acquired and aligned with the tungsten sphere in the reference CT image. The table was shifted per this alignment, and megavoltage anterior-posterior and lateral images were acquired with the electronic portal imaging device. Agreement between the radiation isocenter (based on the MV field) and the center of the sphere (i.e., the alignment point based on kV imaging) was determined for each image via Winston-Lutz analysis. This procedure was repeated 10 times to determine short-term reproducibility, and then repeated daily for 51 days in a clinical setting. The short-term reproducibility test yielded a mean 3D vector displacement of 0.9 ± 0.15 mm between the imaging-based isocenter and the radiation isocenter, with a maximum displacement of 1.1 mm. The clinical reproducibility test yielded a mean displacement of1.1 ± 0.4 mm with a maximum of 2.0 mm when the cube was offset by 5.0 mm, and a mean displacement of 0.9 ± 0.3 mm with a maximum of 1.8 mm when the cube was offset by a random amount. These differences were observed in all directions and were independent of the magnitude of the couch shift. This test was quick and easy to implement clinically and highlighted setup inaccuracies in an image-guided radiation therapy environment. PMID:22955659

  5. Astra: Interdisciplinary study on enhancement of the end-to-end accuracy for spacecraft tracking techniques

    NASA Astrophysics Data System (ADS)

    Iess, Luciano; Di Benedetto, Mauro; James, Nick; Mercolino, Mattia; Simone, Lorenzo; Tortora, Paolo

    2014-02-01

    Navigation of deep-space probes is accomplished through a variety of different radio observables, namely Doppler, ranging and Delta-Differential One-Way Ranging (Delta-DOR). The particular mix of observations used for navigation mainly depends on the available on-board radio system, the mission phase and orbit determination requirements. The accuracy of current ESA and NASA tracking systems is at level of 0.1 mm/s at 60 s integration time for Doppler, 1-5 m for ranging and 6-15 nrad for Delta-DOR measurements in a wide range of operational conditions. The ASTRA study, funded under ESA's General Studies Programme (GSP), addresses the ways to improve the end-to-end accuracy of Doppler, ranging and Delta-DOR systems by roughly a factor of 10. The target accuracies were set to 0.01 mm/s at 60 s integration time for Doppler, 20 cm for ranging and 1 nrad for Delta-DOR. The companies and universities that took part in the study were the University of Rome Sapienza, ALMASpace, BAE Systems and Thales Alenia Space Italy. The analysis of an extensive data set of radio-metric observables and dedicated tests of the ground station allowed consolidating the error budget for each measurement technique. The radio-metric data set comprises X/X, X/Ka and Ka/Ka range and Doppler observables from the Cassini and Rosetta missions. It includes also measurements from the Advanced Media Calibration System (AMCS) developed by JPL for the radio science experiments of the Cassini mission. The error budget for the three radio-metric observables was consolidated by comparing the statistical properties of the data set with the expected error models. The analysis confirmed the contribution from some error sources, but revealed also some discrepancies and ultimately led to improved error models. The error budget reassessment provides adequate information for building guidelines and strategies to effectively improve the navigation accuracies of future deep space missions. We report both on updated

  6. Identifying Elusive Electromagnetic Counterparts to Gravitational Wave Mergers: An End-to-end Simulation

    NASA Astrophysics Data System (ADS)

    Nissanke, Samaya; Kasliwal, Mansi; Georgieva, Alexandra

    2013-04-01

    Combined gravitational wave (GW) and electromagnetic (EM) observations of compact binary mergers should enable detailed studies of astrophysical processes in the strong-field gravity regime. This decade, ground-based GW interferometers promise to routinely detect compact binary mergers. Unfortunately, networks of GW interferometers have poor angular resolution on the sky and their EM signatures are predicted to be faint. Therefore, a challenging goal will be to unambiguously pinpoint the EM counterparts of GW mergers. We perform the first comprehensive end-to-end simulation that focuses on: (1) GW sky localization, distance measures, and volume errors with two compact binary populations and four different GW networks; (2) subsequent EM detectability by a slew of multiwavelength telescopes; and (3) final identification of the merger counterpart amidst a sea of possible astrophysical false positives. First, we find that double neutron star binary mergers can be detected out to a maximum distance of 400 Mpc (or 750 Mpc) by three (or five) detector GW networks, respectively. Neutron-star-black-hole binary mergers can be detected a factor of 1.5 further out; their median to maximum sky localizations are 50-170 deg2 (or 6-65 deg2) for a three (or five) detector GW network. Second, by optimizing depth, cadence, and sky area, we quantify relative fractions of optical counterparts that are detectable by a suite of different aperture-size telescopes across the globe. Third, we present five case studies to illustrate the diversity of scenarios in secure identification of the EM counterpart. We discuss the case of a typical binary, neither beamed nor nearby, and the challenges associated with identifying an EM counterpart at both low and high Galactic latitudes. For the first time, we demonstrate how construction of low-latency GW volumes in conjunction with local universe galaxy catalogs can help solve the problem of false positives. We conclude with strategies that would

  7. SU-E-T-150: End to End Tests On the First Clinical EDGETM

    SciTech Connect

    Scheib, S; Schmelzer, P; Vieira, S; Greco, C

    2014-06-01

    Purpose: To quantify the sub millimeter overall accuracy of EDGETM, the dedicated linac based SRS/SABR treatment platform from Varian, using a novel End-to-End (E2E) test phantom. Methods: The new E2E test phantom developed by Varian consists of a cube with an outer dimension of 15x15x15 cm3. The phantom is equipped with an exchangable inner cube (7×7×7 cm3) to hold radiochromic films or a tungsten ball (diameter = 5 mm) for Winston-Lutz tests. 16 ceramic balls (diameter = 5 mm) are embedded in the outer cube. Three embedded Calypso transponders allow for Calypso based monitoring. The outer surface of the phantom is tracked using the Optical Surface Monitoring System (OSMS). The phantom is positioned using kV, MV and CBCT images. A simCT of the phantom was acquired and SRS/SABR plans were treated using the new phantom on the first clinical installed EDGETM. As a first step a series of EPID based Winston-Lutz tests have been performed. As a second step the calculated dose distribution applied to the phantom was verified with radiochromic films in orthogonal planes. The measured dose distribution is compared with the calculated (Eclipse) one based on the known isocenter on both dose distributions. The geometrical shift needed to match both dose distributions is the overall accuracy and is determined using dose profiles, isodose lines or gamma pass rates (3%, 1 mm). Results: Winston-Lutz tests using the central tungsten BB demonstrated a targeting accuracy of 0.44±0.18mm for jaw (2cm × 2cm) defined 0.39±0.19mm for MLC (2cm × 2cm) defined and 0.37±0.15mm for cone (12.5 mm) defined fields. A treated patient plan (spinal metastases lesion with integrated boost) showed a dosimetric dose localization accuracy of 0.6mm. Conclusion: Geometric and dosimetric E2E tests on EDGETM, show sub-millimeter E2E targeting and dose localisation accuracy.

  8. An End-to-End System to Enable Quick, Easy and Inexpensive Deployment of Hydrometeorological Stations

    NASA Astrophysics Data System (ADS)

    Celicourt, P.; Piasecki, M.

    2014-12-01

    The high cost of hydro-meteorological data acquisition, communication and publication systems along with limited qualified human resources is considered as the main reason why hydro-meteorological data collection remains a challenge especially in developing countries. Despite significant advances in sensor network technologies which gave birth to open hardware and software, low-cost (less than $50) and low-power (in the order of a few miliWatts) sensor platforms in the last two decades, sensors and sensor network deployment remains a labor-intensive, time consuming, cumbersome, and thus expensive task. These factors give rise for the need to develop a affordable, simple to deploy, scalable and self-organizing end-to-end (from sensor to publication) system suitable for deployment in such countries. The design of the envisioned system will consist of a few Sensed-And-Programmed Arduino-based sensor nodes with low-cost sensors measuring parameters relevant to hydrological processes and a Raspberry Pi micro-computer hosting the in-the-field back-end data management. This latter comprises the Python/Django model of the CUAHSI Observations Data Model (ODM) namely DjangODM backed by a PostgreSQL Database Server. We are also developing a Python-based data processing script which will be paired with the data autoloading capability of Django to populate the DjangODM database with the incoming data. To publish the data, the WOFpy (WaterOneFlow Web Services in Python) developed by the Texas Water Development Board for 'Water Data for Texas' which can produce WaterML web services from a variety of back-end database installations such as SQLite, MySQL, and PostgreSQL will be used. A step further would be the development of an appealing online visualization tool using Python statistics and analytics tools (Scipy, Numpy, Pandas) showing the spatial distribution of variables across an entire watershed as a time variant layer on top of a basemap.

  9. IDENTIFYING ELUSIVE ELECTROMAGNETIC COUNTERPARTS TO GRAVITATIONAL WAVE MERGERS: AN END-TO-END SIMULATION

    SciTech Connect

    Nissanke, Samaya; Georgieva, Alexandra; Kasliwal, Mansi

    2013-04-20

    Combined gravitational wave (GW) and electromagnetic (EM) observations of compact binary mergers should enable detailed studies of astrophysical processes in the strong-field gravity regime. This decade, ground-based GW interferometers promise to routinely detect compact binary mergers. Unfortunately, networks of GW interferometers have poor angular resolution on the sky and their EM signatures are predicted to be faint. Therefore, a challenging goal will be to unambiguously pinpoint the EM counterparts of GW mergers. We perform the first comprehensive end-to-end simulation that focuses on: (1) GW sky localization, distance measures, and volume errors with two compact binary populations and four different GW networks; (2) subsequent EM detectability by a slew of multiwavelength telescopes; and (3) final identification of the merger counterpart amidst a sea of possible astrophysical false positives. First, we find that double neutron star binary mergers can be detected out to a maximum distance of 400 Mpc (or 750 Mpc) by three (or five) detector GW networks, respectively. Neutron-star-black-hole binary mergers can be detected a factor of 1.5 further out; their median to maximum sky localizations are 50-170 deg{sup 2} (or 6-65 deg{sup 2}) for a three (or five) detector GW network. Second, by optimizing depth, cadence, and sky area, we quantify relative fractions of optical counterparts that are detectable by a suite of different aperture-size telescopes across the globe. Third, we present five case studies to illustrate the diversity of scenarios in secure identification of the EM counterpart. We discuss the case of a typical binary, neither beamed nor nearby, and the challenges associated with identifying an EM counterpart at both low and high Galactic latitudes. For the first time, we demonstrate how construction of low-latency GW volumes in conjunction with local universe galaxy catalogs can help solve the problem of false positives. We conclude with strategies

  10. End-to-End Self-Assembly of Semiconductor Nanorods in Water by Using an Amphiphilic Surface Design.

    PubMed

    Taniguchi, Yuki; Takishita, Takao; Kawai, Tsuyoshi; Nakashima, Takuya

    2016-02-01

    One-dimensional (1D) self-assemblies of nanocrystals are of interest because of their vectorial and polymer-like dynamic properties. Herein, we report a simple method to prepare elongated assemblies of semiconductor nanorods (NRs) through end-to-end self-assembly. Short-chained water-soluble thiols were employed as surface ligands for CdSe NRs having a wurtzite crystal structure. The site-specific capping of NRs with these ligands rendered the surface of the NRs amphiphilic. The amphiphilic CdSe NRs self-assembled to form elongated wires by end-to-end attachment driven by the hydrophobic effect operating between uncapped NR ends. The end-to-end assembly technique was further applied to CdS NRs and CdSe tetrapods (TPs) with a wurtzite structure. PMID:26836341

  11. Mechanism of Shaft End-To-End Voltage Generation by Asymmetry in an Inverter-Driven Motor

    NASA Astrophysics Data System (ADS)

    Asakura, Yusuke; Akagi, Hirofumi

    This paper deals with the shaft end-to-end voltage resulting from asymmetric stray capacitances in an inverter-driven motor. The origin of the voltage can be any of the following: a ground leakage current, dielectric breakdown in bearings, and asymmetric stray capacitances on stator windings. The third origin seems to be related to the differential-mode current, but the details of the relationship have not been clarified. In this study, differential-mode tests are carried out on an ungrounded motor rated at 400V and 15kW, and the shaft end-to-end voltage generation by the asymmetric stray capacitances is theoretically discussed. Finaly, a winding model is presented for the purpose of understanding the mechanism responsible for the shaft end-to-end voltage.

  12. Achieving End-to-End QoS in the Next Generation Internet: Integrated Services over Differentiated Service Networks

    NASA Technical Reports Server (NTRS)

    Bai, Haowei; Atiquzzaman, Mohammed; Ivancic, William

    2001-01-01

    Currently there are two approaches to provide Quality of Service (QoS) in the next generation Internet: An early one is the Integrated Services (IntServ) with the goal of allowing end-to-end QoS to be provided to applications; the other one is the Differentiated Services (DiffServ) architecture providing QoS in the backbone. In this context, a DiffServ network may be viewed as a network element in the total end-to-end path. The objective of this paper is to investigate the possibility of providing end-to-end QoS when IntServ runs over DiffServ backbone in the next generation Internet. Our results show that the QoS requirements of IntServ applications can be successfully achieved when IntServ traffic is mapped to the DiffServ domain in next generation Internet.

  13. Achieving End-to-End QoS in the Next Generation Internet: Integrated Services Over Differentiated Service Networks

    NASA Technical Reports Server (NTRS)

    Bai, Haowei; Atiquzzaman, Mohammed; Ivancic, William

    2001-01-01

    Currently there are two approaches to provide Quality of Service (QoS) in the next generation Internet: An early one is the Integrated Services (IntServ) with the goal of allowing end-to-end QoS to be provided to applications; the other one is the Differentiated Services (DiffServ) architecture providing QoS in the backbone. In this context, a DiffServ network may be viewed as a network element in the total end-to-end path. The objective of this paper is to investigate the possibility of providing end-to-end QoS when IntServ runs over DiffServ backbone in the next generation Internet. Our results show that the QoS requirements of IntServ applications can be successfully achieved when IntServ traffic is mapped to the DiffServ domain in next generation Internet.

  14. Metal-Metal and π-π Interactions Directed End-to-End Assembly of Gold Nanorods.

    PubMed

    Leung, Frankie Chi-Ming; Leung, Sammual Yu-Lut; Chung, Clive Yik-Sham; Yam, Vivian Wing-Wah

    2016-03-01

    The end-to-end aggregation of gold nanorods (GNRs) has been demonstrated to be directed by a thioacetate-containing alkynylplatinum(II) terpyridine complex. The in situ deprotected complex is preferentially attached at the ends of the gold nanorods (GNRs) and induce the aggregation of GNRs in an "end-to-end" manner by Pt···Pt and π-π interactions, which have been characterized by electron microscopy, energy dispersed X-ray (EDX) analysis, and UV-vis absorption spectroscopy. The assembly of the nanorods into chain-like nanostructures can be controlled by the concentration of the Pt(II) complexes. PMID:26914346

  15. Influence of end-to-end diffusion on intramolecular energy transfer as observed by frequency-domain fluorometry

    NASA Astrophysics Data System (ADS)

    Lakowicz, Joseph R.; Wiczk, Wieslaw M.; Gryczynski, Ignacy; Szmacinski, Henryk; Johnson, Michael L.

    1990-05-01

    We investigated the influence of end-to-end diffusion on intramolecular energy transfer between a naphthalene donor and dansyl acceptor linked by polymethylene chain. A range of viscosities of 0.6 - 200cP were obtained using propylene glycol at different temperatures (0-80°C) and methanol at 20°C. The intensity decays of naphthalene were measured in frequency-domain. Several theoretical models, including distance distributions were used to fit the data. The results indicate that end-to-end diffusion of flexible donor - acceptor pairs can be readily detected and quantified using frequency-domain fluorometry.

  16. On the importance of risk knowledge for an end-to-end tsunami early warning system

    NASA Astrophysics Data System (ADS)

    Post, Joachim; Strunz, Günter; Riedlinger, Torsten; Mück, Matthias; Wegscheider, Stephanie; Zosseder, Kai; Steinmetz, Tilmann; Gebert, Niklas; Anwar, Herryal

    2010-05-01

    context has been worked out. The generated results contribute significantly in the fields of (1) warning decision and warning levels, (2) warning dissemination and warning message content, (3) early warning chain planning, (4) increasing response capabilities and protective systems, (5) emergency relief and (6) enhancing communities' awareness and preparedness towards tsunami threats. Additionally examples will be given on the potentials of an operational use of risk information in early warning systems as first experiences exist for the tsunami early warning center in Jakarta, Indonesia. Beside this the importance of linking national level early warning information with tsunami risk information available at the local level (e.g. linking warning message information on expected intensity with respective tsunami hazard zone maps at community level for effective evacuation) will be demonstrated through experiences gained in three pilot areas in Indonesia. The presentation seeks to provide new insights on benefits using risk information in early warning and will provide further evidence that practical use of risk information is an important and indispensable component of end-to-end early warning.

  17. SensorKit: An End-to-End Solution for Environmental Sensor Networking

    NASA Astrophysics Data System (ADS)

    Silva, F.; Graham, E.; Deschon, A.; Lam, Y.; Goldman, J.; Wroclawski, J.; Kaiser, W.; Benzel, T.

    2008-12-01

    Modern day sensor network technology has shown great promise to transform environmental data collection. However, despite the promise, these systems have remained the purview of the engineers and computer scientists who design them rather than a useful tool for the environmental scientists who need them. SensorKit is conceived of as a way to make wireless sensor networks accessible to The People: it is an advanced, powerful tool for sensor data collection that does not require advanced technological know-how. We are aiming to make wireless sensor networks for environmental science as simple as setting up a standard home computer network by providing simple, tested configurations of commercially-available hardware, free and easy-to-use software, and step-by-step tutorials. We designed and built SensorKit using a simplicity-through-sophistication approach, supplying users a powerful sensor to database end-to-end system with a simple and intuitive user interface. Our objective in building SensorKit was to make the prospect of using environmental sensor networks as simple as possible. We built SensorKit from off the shelf hardware components, using the Compact RIO platform from National Instruments for data acquisition due to its modular architecture and flexibility to support a large number of sensor types. In SensorKit, we support various types of analog, digital and networked sensors. Our modular software architecture allows us to abstract sensor details and provide users a common way to acquire data and to command different types of sensors. SensorKit is built on top of the Sensor Processing and Acquisition Network (SPAN), a modular framework for acquiring data in the field, moving it reliably to the scientist institution, and storing it in an easily-accessible database. SPAN allows real-time access to the data in the field by providing various options for long haul communication, such as cellular and satellite links. Our system also features reliable data storage

  18. Unidata's Vision for Providing Comprehensive and End-to-end Data Services

    NASA Astrophysics Data System (ADS)

    Ramamurthy, M. K.

    2009-05-01

    This paper presents Unidata's vision for providing comprehensive, well-integrated, and end-to-end data services for the geosciences. These include an array of functions for collecting, finding, and accessing data; data management tools for generating, cataloging, and exchanging metadata; and submitting or publishing, sharing, analyzing, visualizing, and integrating data. When this vision is realized, users no matter where they are or how they are connected to the Internetwill be able to find and access a plethora of geosciences data and use Unidata-provided tools and services both productively and creatively in their research and education. What that vision means for the Unidata community is elucidated by drawing a simple analogy. Most of users are familiar with Amazon and eBay e-commerce sites and content sharing sites like YouTube and Flickr. On the eBay marketplace, people can sell practically anything at any time and buyers can share their experience of purchasing a product or the reputation of a seller. Likewise, at Amazon, thousands of merchants sell their goods and millions of customers not only buy those goods, but provide a review or opinion of the products they buy and share their experiences as purchasers. Similarly, YouTube and Flickr are sites tailored to video- and photo-sharing, respectively, where users can upload their own content and share it with millions of other users, including family and friends. What all these sites, together with social-networking applications like MySpace and Facebook, have enabled is a sense of a virtual community in which users can search and browse products or content, comment and rate those products from anywhere, at any time, and via any Internet- enabled device like an iPhone, laptop, or a desktop computer. In essence, these enterprises have fundamentally altered people's buying modes and behavior toward purchases. Unidata believes that similar approaches, appropriately tailored to meet the needs of the scientific

  19. A vision for end-to-end data services to foster international partnerships through data sharing

    NASA Astrophysics Data System (ADS)

    Ramamurthy, M.; Yoksas, T.

    2009-04-01

    Increasingly, the conduct of science requires scientific partnerships and sharing of knowledge, information, and other assets. This is particularly true in our field where the highly-coupled Earth system and its many linkages have heightened the importance of collaborations across geographic, disciplinary, and organizational boundaries. The climate system, for example, is far too complex a puzzle to be unraveled by individual investigators or nations. As articulated in the NSF Strategic Plan: FY 2006-2011, "…discovery increasingly requires expertise of individuals from different disciplines, with diverse perspectives, and often from different nations, working together to accommodate the extraordinary complexity of today's science and engineering challenges." The Nobel Prize winning IPCC assessments are a prime example of such an effort. Earth science education is also uniquely suited to drawing connections between the dynamic Earth system and societal issues. Events like the 2004 Indian Ocean tsunami and Hurricane Katrina provide ample evidence of this relevance, as they underscore the importance of timely and interdisciplinary integration and synthesis of data. Our success in addressing such complex problems and advancing geosciences depends on the availability of a state-of-the-art and robust cyberinfrastructure, transparent and timely access to high-quality data from diverse sources, and requisite tools to integrate and use the data effectively, toward creating new knowledge. To that end, Unidata's vision calls for providing comprehensive, well-integrated, and end-to-end data services for the geosciences. These include an array of functions for collecting, finding, and accessing data; data management tools for generating, cataloging, and exchanging metadata; and submitting or publishing, sharing, analyzing, visualizing, and integrating data. When this vision is realized, users — no matter where they are, how they are connected to the Internet, or what

  20. Integration proposal through standard-based design of an end-to-end platform for p-Health environments.

    PubMed

    Martíínez, I; Trigo, J D; Martínez-Espronceda, M; Escayola, J; Muñoz, P; Serrano, L; García, J

    2009-01-01

    Interoperability among medical devices and compute engines in the personal environment of the patient, and with healthcare information systems in the remote monitoring and management process is a key need that requires developments supported on standard-based design. Even though there have been some international initiatives to combine different standards, the vision of an entire end-to-end standard-based system is the next challenge. This paper presents the implementation guidelines of a ubiquitous platform for Personal Health (p-Health). It is standard-based using the two main medical norms in this context: ISO/IEEE11073 in the patient environment for medical device interoperability, and EN13606 to allow the interoperable communication of the Electronic Healthcare Record of the patient. Furthermore, the proposal of a new protocol for End-to-End Standard Harmonization (E2ESHP) is presented in order to make possible the end-to-end standard integration. The platform has been designed to comply with the last ISO/IEEE11073 and EN13606 available versions, and tested in a laboratory environment as a proof-of-concept to illustrate its feasibility as an end-to-end standard-based solution. PMID:19963613

  1. Wiener restoration of sampled image data - End-to-end analysis

    NASA Technical Reports Server (NTRS)

    Fales, Carl L.; Huck, Friedrich O.; Mccormick, Judith A.; Park, Stephen K.

    1988-01-01

    The Wiener filter is formulated as a function of the basic image-gathering and image-reconstruction constraints, thereby providing a method for minimizing the mean-squared error between the (continuous-input) radiance field and its restored (continuous-output) representation. This formulation of the Wiener filter is further extended to the Wiener-characteristic filter, which provides a method for explicitly specifying the desired representation. Two specific examples of Wiener filters are presented.

  2. A vision for end-to-end data services to foster international partnerships through data sharing

    NASA Astrophysics Data System (ADS)

    Ramamurthy, M.; Yoksas, T.

    2009-04-01

    Increasingly, the conduct of science requires scientific partnerships and sharing of knowledge, information, and other assets. This is particularly true in our field where the highly-coupled Earth system and its many linkages have heightened the importance of collaborations across geographic, disciplinary, and organizational boundaries. The climate system, for example, is far too complex a puzzle to be unraveled by individual investigators or nations. As articulated in the NSF Strategic Plan: FY 2006-2011, "…discovery increasingly requires expertise of individuals from different disciplines, with diverse perspectives, and often from different nations, working together to accommodate the extraordinary complexity of today's science and engineering challenges." The Nobel Prize winning IPCC assessments are a prime example of such an effort. Earth science education is also uniquely suited to drawing connections between the dynamic Earth system and societal issues. Events like the 2004 Indian Ocean tsunami and Hurricane Katrina provide ample evidence of this relevance, as they underscore the importance of timely and interdisciplinary integration and synthesis of data. Our success in addressing such complex problems and advancing geosciences depends on the availability of a state-of-the-art and robust cyberinfrastructure, transparent and timely access to high-quality data from diverse sources, and requisite tools to integrate and use the data effectively, toward creating new knowledge. To that end, Unidata's vision calls for providing comprehensive, well-integrated, and end-to-end data services for the geosciences. These include an array of functions for collecting, finding, and accessing data; data management tools for generating, cataloging, and exchanging metadata; and submitting or publishing, sharing, analyzing, visualizing, and integrating data. When this vision is realized, users — no matter where they are, how they are connected to the Internet, or what

  3. Spectrum reconstruction based on the constrained optimal linear inverse methods.

    PubMed

    Ren, Wenyi; Zhang, Chunmin; Mu, Tingkui; Dai, Haishan

    2012-07-01

    The dispersion effect of birefringent material results in spectrally varying Nyquist frequency for the Fourier transform spectrometer based on birefringent prism. Correct spectral information cannot be retrieved from the observed interferogram if the dispersion effect is not appropriately compensated. Some methods, such as nonuniform fast Fourier transforms and compensation method, were proposed to reconstruct the spectrum. In this Letter, an alternative constrained spectrum reconstruction method is suggested for the stationary polarization interference imaging spectrometer (SPIIS) based on the Savart polariscope. In the theoretical model of the interferogram, the noise and the total measurement error are included, and the spectrum reconstruction is performed by using the constrained optimal linear inverse methods. From numerical simulation, it is found that the proposed method is much more effective and robust than the nonconstrained spectrum reconstruction method proposed by Jian, and provides a useful spectrum reconstruction approach for the SPIIS. PMID:22743461

  4. End-to-End Demonstrator of the Safe Affordable Fission Engine (SAFE) 30: Power Conversion and Ion Engine Operation

    NASA Technical Reports Server (NTRS)

    Hrbud, Ivana; VanDyke, Melissa; Houts, Mike; Goodfellow, Keith; Schafer, Charles (Technical Monitor)

    2001-01-01

    The Safe Affordable Fission Engine (SAFE) test series addresses Phase 1 Space Fission Systems issues in particular non-nuclear testing and system integration issues leading to the testing and non-nuclear demonstration of a 400-kW fully integrated flight unit. The first part of the SAFE 30 test series demonstrated operation of the simulated nuclear core and heat pipe system. Experimental data acquired in a number of different test scenarios will validate existing computational models, demonstrated system flexibility (fast start-ups, multiple start-ups/shut downs), simulate predictable failure modes and operating environments. The objective of the second part is to demonstrate an integrated propulsion system consisting of a core, conversion system and a thruster where the system converts thermal heat into jet power. This end-to-end system demonstration sets a precedent for ground testing of nuclear electric propulsion systems. The paper describes the SAFE 30 end-to-end system demonstration and its subsystems.

  5. End-to-End demonstrator of the Safe Affordable Fission Engine (SAFE) 30: Power conversion and ion engine operation

    NASA Astrophysics Data System (ADS)

    Hrbud, Ivana; van Dyke, Melissa; Houts, Mike; Goodfellow, Keith

    2002-01-01

    The Safe Affordable Fission Engine (SAFE) test series addresses Phase 1 Space Fission Systems issues in particular non-nuclear testing and system integration issues leading to the testing and non-nuclear demonstration of a 400-kW fully integrated flight unit. The first part of the SAFE 30 test series demonstrated operation of the simulated nuclear core and heat pipe system. Experimental data acquired in a number of different test scenarios will validate existing computational models, demonstrated system flexibility (fast start-ups, multiple start-ups/shut downs), simulate predictable failure modes and operating environments. The objective of the second part is to demonstrate an integrated propulsion system consisting of a core, conversion system and a thruster where the system converts thermal heat into jet power. This end-to-end system demonstration sets a precedent for ground testing of nuclear electric propulsion systems. The paper describes the SAFE 30 end-to-end system demonstration and its subsystems. .

  6. POST2 End-To-End Descent and Landing Simulation for the Autonomous Landing and Hazard Avoidance Technology Project

    NASA Technical Reports Server (NTRS)

    Fisher, Jody l.; Striepe, Scott A.

    2007-01-01

    The Program to Optimize Simulated Trajectories II (POST2) is used as a basis for an end-to-end descent and landing trajectory simulation that is essential in determining the design and performance capability of lunar descent and landing system models and lunar environment models for the Autonomous Landing and Hazard Avoidance Technology (ALHAT) project. This POST2-based ALHAT simulation provides descent and landing simulation capability by integrating lunar environment and lander system models (including terrain, sensor, guidance, navigation, and control models), along with the data necessary to design and operate a landing system for robotic, human, and cargo lunar-landing success. This paper presents the current and planned development and model validation of the POST2-based end-to-end trajectory simulation used for the testing, performance and evaluation of ALHAT project system and models.

  7. Minimizing End-to-End Interference in I/O Stacks Spanning Shared Multi-Level Buffer Caches

    ERIC Educational Resources Information Center

    Patrick, Christina M.

    2011-01-01

    This thesis presents an end-to-end interference minimizing uniquely designed high performance I/O stack that spans multi-level shared buffer cache hierarchies accessing shared I/O servers to deliver a seamless high performance I/O stack. In this thesis, I show that I can build a superior I/O stack which minimizes the inter-application interference…

  8. A Novel Vascular Coupling System for End-to-End Anastomosis.

    PubMed

    Li, Huizhong; Gale, Bruce K; Sant, Himanshu; Shea, Jill; David Bell, E; Agarwal, Jay

    2015-09-01

    Vascular anastomosis is common during reconstructive surgeries. Traditional hand-suturing techniques are time consuming, subject to human error, and require high technical expertise and complex instruments. Prior attempts to replace hand-suturing technique, including staples, ring-pin devices, cuffing devices, and clips, are either more cumbersome, are unable to maintain a tight seal, or do not work for both arteries and veins. To provide a more efficient and reliable vessel anastomosis, a metal-free vascular coupling system that can be used for both arteries and veins was designed, fabricated and tested. A set of corresponding instruments were developed to facilitate the anastomosis process. Evaluation of the anastomosis by scanning electron microscopy and magnetic resonance imaging, demonstrated that the installation process does not cause damage to the vessel intima and the vascular coupling system is not exposed to the vessel lumen. Mechanical testing results showed that vessels reconnected with the vascular coupling system could withstand 12.7 ± 2.2 N tensile force and have superior leak profiles (0.049 ± 0.015, 0.078 ± 0.016, 0.089 ± 0.008 mL/s at 160, 260, 360 mmHg, respectively) compared to hand sutured vessels (0.310 ± 0.014, 1.123 ± 0.033, 2.092 ± 0.072 mL/s at 160, 260, 360 mmHg, respectively). The anastomotic process was successfully demonstrated on both arteries and veins in cadaver pigs. PMID:26577362

  9. Influence of DBT reconstruction algorithm on power law spectrum coefficient

    NASA Astrophysics Data System (ADS)

    Vancamberg, Laurence; Carton, Ann-Katherine; Abderrahmane, Ilyes H.; Palma, Giovanni; Milioni de Carvalho, Pablo; Iordache, Rǎzvan; Muller, Serge

    2015-03-01

    In breast X-ray images, texture has been characterized by a noise power spectrum (NPS) that has an inverse power-law shape described by its slope β in the log-log domain. It has been suggested that the magnitude of the power-law spectrum coefficient β is related to mass lesion detection performance. We assessed β in reconstructed digital breast tomosynthesis (DBT) images to evaluate its sensitivity to different typical reconstruction algorithms including simple back projection (SBP), filtered back projection (FBP) and a simultaneous iterative reconstruction algorithm (SIRT 30 iterations). Results were further compared to the β coefficient estimated from 2D central DBT projections. The calculations were performed on 31 unilateral clinical DBT data sets and simulated DBT images from 31 anthropomorphic software breast phantoms. Our results show that β highly depends on the reconstruction algorithm; the highest β values were found for SBP, followed by reconstruction with FBP, while the lowest β values were found for SIRT. In contrast to previous studies, we found that β is not always lower in reconstructed DBT slices, compared to 2D projections and this depends on the reconstruction algorithm. All β values estimated in DBT slices reconstructed with SBP were larger than β values from 2D central projections. Our study also shows that the reconstruction algorithm affects the symmetry of the breast texture NPS; the NPS of clinical cases reconstructed with SBP exhibit the highest symmetry, while the NPS of cases reconstructed with SIRT exhibit the highest asymmetry.

  10. Mechanical loading of peripheral nerves during remobilisation of the affected member after end-to-end anastomosis.

    PubMed

    Orf, G; Wüst, R

    1979-01-01

    Our study involved simulating end-to-end neurorrhaphy of the sciatic nerve in a number of rabbits and analysing in vivo the mechanical loads acting on the nerve while the affected member was being remobilised. We found both the suture and mobilisation loads to be related to the size of the nerve defect. In each case, traction force, strain, and stress were proportional. The effect which these experimental findings may have on the future use of flexing neighbouring joints as a "manipulative" measure to achieve a tension-free nerve suture will be discussed. PMID:525461

  11. End-to-end testing. [to verify electrical equipment failure due to carbon fibers released in aircraft-fuel fires

    NASA Technical Reports Server (NTRS)

    Pride, R. A.

    1979-01-01

    The principle objective of the kinds of demonstration tests that are discussed is to try to verify whether or not carbon fibers that are released by burning composite parts in an aircraft-fuel fires can produce failures in electrical equipment. A secondary objective discussed is to experimentally validate the analytical models for some of the key elements in the risk analysis. The approach to this demonstration testing is twofold: limited end-to-end test are to be conducted in a shock tube; and planning for some large outdoor burn tests is being done.

  12. End-to-End Study of the Transfer of Energy from Magnetosheath Ion Precipitation to the Cusp

    NASA Technical Reports Server (NTRS)

    Coffey, V. N.; Chandler, M. O.; Singh, Nagendra; Avanov, Levon

    2005-01-01

    This paper describes a study of the effects of unstable magnetosheath distributions on the cusp ionosphere. An end-to-end numerical model was used to study, first, the evolved distributions from precipitation due to reconnection and, secondly, the energy transfer into the high latitude ionosphere based on these solar wind/magnetosheath inputs. Using inputs of several representative examples of magnetosheath injections, waves were generated at the lower hybrid frequency and energy transferred to the ionospheric electrons and ions. The resulting wave spectra and ion and electron particle heating was analyzed. Keywords: Ion heating: Magnetosheath/Ionosphere coupling: Particle/Wave Interactions. Simulations

  13. Automated Design of Propellant-Optimal, End-to-End, Low-Thrust Trajectories for Trojan Asteroid Tours

    NASA Technical Reports Server (NTRS)

    Stuart, Jeffrey; Howell, Kathleen; Wilson, Roby

    2013-01-01

    The Sun-Jupiter Trojan asteroids are celestial bodies of great scientific interest as well as potential resources offering water and other mineral resources for longterm human exploration of the solar system. Previous investigations under this project have addressed the automated design of tours within the asteroid swarm. This investigation expands the current automation scheme by incorporating options for a complete trajectory design approach to the Trojan asteroids. Computational aspects of the design procedure are automated such that end-to-end trajectories are generated with a minimum of human interaction after key elements and constraints associated with a proposed mission concept are specified.

  14. The Kepler End-to-End Model: Creating High-Fidelity Simulations to Test Kepler Ground Processing

    NASA Technical Reports Server (NTRS)

    Bryson, Stephen T.; Jenkins, Jon M.; Peters, Dan J.; Tenenbaum, Peter P.; Klaus, Todd C.; Gunter, Jay P.; Cote, Miles T.; Caldwell, Douglas A.

    2010-01-01

    The Kepler mission is designed to detect the transit of Earth-like planets around Sun-like stars by observing 100,000 stellar targets. Developing and testing the Kepler ground-segment processing system, in particular the data analysis pipeline, requires high-fidelity simulated data. This simulated data is provided by the Kepler End-to-End Model (ETEM). ETEM simulates the astrophysics of planetary transits and other phenomena, properties of the Kepler spacecraft and the format of the downlinked data. Major challenges addressed by ETEM include the rapid production of large amounts of simulated data, extensibility and maintainability.

  15. Evaluation of the end-to-end distance of chains solubilized in a polymer Langmuir monolayer by atomic force microscopy

    NASA Astrophysics Data System (ADS)

    Kumaki, Jiro

    Polymer chain packing in two-dimensional (2D) condense state is still not well understood. Direct observation of the chain packing in a monolayer should be the best way to understand this, however, it is still difficult even using atomic force microscopy (AFM) except for extraordinarily thick polymers. In this study, we successfully evaluate the end-to-end distance of the chains in a Langmuir-Blodgett monolayer composed of a conventional polymer by AFM. We successfully solubilized a small amount of a polystyrene-b-poly(methyl methacrylate)-b-polystyrene (PS-b-PMMA-b-PS) triblock copolymer in a PMMA Langmuir monolayer with the PS blocks being condensed as single-PS-block particles which could be used as a probe of the position of the chain ends. The evaluated end-to-end distance was 2.5 times longer than that of the 2D ideal chain, indicating the chains in the 2D monolayer are not strongly segregated but interpenetrates into other chains.

  16. Context-driven, prescription-based personal activity classification: methodology, architecture, and end-to-end implementation.

    PubMed

    Xu, James Y; Chang, Hua-I; Chien, Chieh; Kaiser, William J; Pottie, Gregory J

    2014-05-01

    Enabling large-scale monitoring and classification of a range of motion activities is of primary importance due to the need by healthcare and fitness professionals to monitor exercises for quality and compliance. Past work has not fully addressed the unique challenges that arise from scaling. This paper presents a novel end-to-end system solution to some of these challenges. The system is built on the prescription-based context-driven activity classification methodology. First, we show that by refining the definition of context, and introducing the concept of scenarios, a prescription model can provide personalized activity monitoring. Second, through a flexible architecture constructed from interface models, we demonstrate the concept of a context-driven classifier. Context classification is achieved through a classification committee approach, and activity classification follows by means of context specific activity models. Then, the architecture is implemented in an end-to-end system featuring an Android application running on a mobile device, and a number of classifiers as core classification components. Finally, we use a series of experimental field evaluations to confirm the expected benefits of the proposed system in terms of classification accuracy, rate, and sensor operating life. PMID:24107984

  17. Far-Infrared Therapy Promotes Nerve Repair following End-to-End Neurorrhaphy in Rat Models of Sciatic Nerve Injury

    PubMed Central

    Chen, Tai-Yuan; Yang, Yi-Chin; Sha, Ya-Na; Chou, Jiun-Rou

    2015-01-01

    This study employed a rat model of sciatic nerve injury to investigate the effects of postoperative low-power far-infrared (FIR) radiation therapy on nerve repair following end-to-end neurorrhaphy. The rat models were divided into the following 3 groups: (1) nerve injury without FIR biostimulation (NI/sham group); (2) nerve injury with FIR biostimulation (NI/FIR group); and (3) noninjured controls (normal group). Walking-track analysis results showed that the NI/FIR group exhibited significantly higher sciatic functional indices at 8 weeks after surgery (P < 0.05) compared with the NI/sham group. The decreased expression of CD4 and CD8 in the NI/FIR group indicated that FIR irradiation modulated the inflammatory process during recovery. Compared with the NI/sham group, the NI/FIR group exhibited a significant reduction in muscle atrophy (P < 0.05). Furthermore, histomorphometric assessment indicated that the nerves regenerated more rapidly in the NI/FIR group than in the NI/sham group; furthermore, the NI/FIR group regenerated neural tissue over a larger area, as well as nerve fibers of greater diameter and with thicker myelin sheaths. Functional recovery, inflammatory response, muscular reinnervation, and histomorphometric assessment all indicated that FIR radiation therapy can accelerate nerve repair following end-to-end neurorrhaphy of the sciatic nerve. PMID:25722734

  18. Effect of swirling flow on platelet concentration distribution in small-caliber artificial grafts and end-to-end anastomoses

    NASA Astrophysics Data System (ADS)

    Zhan, Fan; Fan, Yu-Bo; Deng, Xiao-Yan

    2011-10-01

    Platelet concentration near the blood vessel wall is one of the major factors in the adhesion of platelets to the wall. In our previous studies, it was found that swirling flows could suppress platelet adhesion in small-caliber artificial grafts and end-to-end anastomoses. In order to better understand the beneficial effect of the swirling flow, we numerically analyzed the near-wall concentration distribution of platelets in a straight tube and a sudden tubular expansion tube under both swirling flow and normal flow conditions. The numerical models were created based on our previous experimental studies. The simulation results revealed that when compared with the normal flow, the swirling flow could significantly reduce the near-wall concentration of platelets in both the straight tube and the expansion tube. The present numerical study therefore indicates that the reduction in platelet adhesion under swirling flow conditions in small-caliber arterial grafts, or in end-to-end anastomoses as observed in our previous experimental study, was possibly through a mechanism of platelet transport, in which the swirling flow reduced the near-wall concentration of platelets.

  19. Image gathering, coding, and processing: End-to-end optimization for efficient and robust acquisition of visual information

    NASA Technical Reports Server (NTRS)

    Huck, Friedrich O.; Fales, Carl L.

    1990-01-01

    Researchers are concerned with the end-to-end performance of image gathering, coding, and processing. The applications range from high-resolution television to vision-based robotics, wherever the resolution, efficiency and robustness of visual information acquisition and processing are critical. For the presentation at this workshop, it is convenient to divide research activities into the following two overlapping areas: The first is the development of focal-plane processing techniques and technology to effectively combine image gathering with coding, with an emphasis on low-level vision processing akin to the retinal processing in human vision. The approach includes the familiar Laplacian pyramid, the new intensity-dependent spatial summation, and parallel sensing/processing networks. Three-dimensional image gathering is attained by combining laser ranging with sensor-array imaging. The second is the rigorous extension of information theory and optimal filtering to visual information acquisition and processing. The goal is to provide a comprehensive methodology for quantitatively assessing the end-to-end performance of image gathering, coding, and processing.

  20. A GF-Matrix Approach to the End-to-End Coupling in Ethane-like Molecules

    NASA Astrophysics Data System (ADS)

    Dilauro, C.; Lattanzi, F.

    1993-12-01

    We examine the effect of end-to-end coupling on the degenerate vibrational deformations of ethane-like molecules by considering the form of the dependence of the elements of the G and F matrices on the internal rotation angle γ. This can be done by simple geometrical considerations, in a basis of internal vibrational coordinates. After transformation to symmetry coordinates belonging to different species of the G36(EM) extended molecular group, the product G(0)F(0) of the γ-independent parts of the G and F matrices is diagonalized. The resulting zero-order normal modes and their conjugate momenta are used in building up the vibration-torsion Hamiltonian, including the γ-dependent terms. We find that (i) in the case of a low barrier hindering the internal rotation the most convenient sets of degenerate normal coordinates are either Gs (in the case of a weak effect of the end-to-end coupling on the relative deformations) or E1d, E2d; (ii) degenerate vibrational coordinates whose top and frame components have at the least one common atom lead to E1d, E2d normal modes regardless of the barrier height; (iii) "unpaired" degenerate vibrational coordinates, such as the skeletal bending of dimethylzinc, always contribute an E1d normal mode; and (iv) in the case of high or moderate barriers, Gs normal modes are unlikely to occur, and the most probable normal mode symmetries are E1d, E2d.

  1. Performances of the fractal iterative method with an internal model control law on the ESO end-to-end ELT adaptive optics simulator

    NASA Astrophysics Data System (ADS)

    Béchet, C.; Le Louarn, M.; Tallon, M.; Thiébaut, É.

    2008-07-01

    Adaptive Optics systems under study for the Extremely Large Telescopes gave rise to a new generation of algorithms for both wavefront reconstruction and the control law. In the first place, the large number of controlled actuators impose the use of computationally efficient methods. Secondly, the performance criterion is no longer solely based on nulling residual measurements. Priors on turbulence must be inserted. In order to satisfy these two requirements, we suggested to associate the Fractal Iterative Method for the estimation step with an Internal Model Control. This combination has now been tested on an end-to-end adaptive optics numerical simulator at ESO, named Octopus. Results are presented here and performance of our method is compared to the classical Matrix-Vector Multiplication combined with a pure integrator. In the light of a theoretical analysis of our control algorithm, we investigate the influence of several errors contributions on our simulations. The reconstruction error varies with the signal-to-noise ratio but is limited by the use of priors. The ratio between the system loop delay and the wavefront coherence time also impacts on the reachable Strehl ratio. Whereas no instabilities are observed, correction quality is obviously affected at low flux, when subapertures extinctions are frequent. Last but not least, the simulations have demonstrated the robustness of the method with respect to sensor modeling errors and actuators misalignments.

  2. Morphological study of the healing process after diode laser-assisted end-to-end microanastomosis: comparison with conventional manual suture

    NASA Astrophysics Data System (ADS)

    Tang, Jing; Rouy, Simone; Prudhomme, Michel; Godlewski, Guilhem; Chambettaz, Francois; Delacretaz, Guy P.; Salathe, Rene-Paul

    1996-01-01

    A series of carotid end-to-end diode laser assisted microvascular anastomosis (LAMA) versus control ateral conventional suture microanastomosis (CMA) were performed in 120 Wistar rats (in the same animal, LAMA performed in the left side and CMA in the right). The optic and scanning electron microscopic examinations were assessed from day 0 to day 210. The results revealed that on day 0 LAMA gave rise to proteins deneturation and collagens fusion of the media and adventitia in the arterial wall. Re-endothelialization of anastomotic line began at day 3, as well as a large number of inflammatory aggregated in the adventitia. On day 10 the endothelial cells were restored on the anastomotic site and collagenous network developed in the media. On day 90 proliferation and disorientation of the elastic fibers appeared. A part of elastic laminae had been reconstructed on day 210. In the group CMA, the re- endothelialization developed later than LAMA, and the reconstruction of the elastic laminae failed to happen until day 210. These data suggest that the results of long term healing process after diode LAMA is better than that of CMA in normal artery repair.

  3. HITSZ_CDR: an end-to-end chemical and disease relation extraction system for BioCreative V

    PubMed Central

    Li, Haodi; Tang, Buzhou; Chen, Qingcai; Chen, Kai; Wang, Xiaolong; Wang, Baohua; Wang, Zhe

    2016-01-01

    In this article, an end-to-end system was proposed for the challenge task of disease named entity recognition (DNER) and chemical-induced disease (CID) relation extraction in BioCreative V, where DNER includes disease mention recognition (DMR) and normalization (DN). Evaluation on the challenge corpus showed that our system achieved the highest F1-scores 86.93% on DMR, 84.11% on DN, 43.04% on CID relation extraction, respectively. The F1-score on DMR is higher than our previous one reported by the challenge organizers (86.76%), the highest F1-score of the challenge. Database URL: http://database.oxfordjournals.org/content/2016/baw077 PMID:27270713

  4. End-To-End Risk Assesment: From Genes and Protein to Acceptable Radiation Risks for Mars Exploration

    NASA Astrophysics Data System (ADS)

    Cucinotta, Francis A.; Schimmerling, Walter

    2000-07-01

    The human exploration of Mars will impose unavoidable health risks from galactic cosmic rays (GCR) and possibly solar particle events (SPE). It is the goal of NASA's Space Radiation Health Program to develop the capability to predict health risks with significant accuracy to ensure that risks are well below acceptable levels and to allow for mitigation approaches to be effective at reasonable costs. End-to-End risk assessment is the approach being followed to understand proton and heavy ion damage at the molecular, cellular, and tissue levels in order to predict the probability of the major health risk including cancer, neurological disorders, hereditary effects, cataracts, and acute radiation sickness and to develop countermeasures for mitigating risks.

  5. NASA End-to-End Data System /NEEDS/ information adaptive system - Performing image processing onboard the spacecraft

    NASA Technical Reports Server (NTRS)

    Kelly, W. L.; Howle, W. M.; Meredith, B. D.

    1980-01-01

    The Information Adaptive System (IAS) is an element of the NASA End-to-End Data System (NEEDS) Phase II and is focused toward onbaord image processing. Since the IAS is a data preprocessing system which is closely coupled to the sensor system, it serves as a first step in providing a 'Smart' imaging sensor. Some of the functions planned for the IAS include sensor response nonuniformity correction, geometric correction, data set selection, data formatting, packetization, and adaptive system control. The inclusion of these sensor data preprocessing functions onboard the spacecraft will significantly improve the extraction of information from the sensor data in a timely and cost effective manner and provide the opportunity to design sensor systems which can be reconfigured in near real time for optimum performance. The purpose of this paper is to present the preliminary design of the IAS and the plans for its development.

  6. End-to-End Trajectory for Conjunction Class Mars Missions Using Hybrid Solar-Electric/Chemical Transportation System

    NASA Technical Reports Server (NTRS)

    Chai, Patrick R.; Merrill, Raymond G.; Qu, Min

    2016-01-01

    NASA's Human Spaceflight Architecture Team is developing a reusable hybrid transportation architecture in which both chemical and solar-electric propulsion systems are used to deliver crew and cargo to exploration destinations. By combining chemical and solar-electric propulsion into a single spacecraft and applying each where it is most effective, the hybrid architecture enables a series of Mars trajectories that are more fuel efficient than an all chemical propulsion architecture without significant increases to trip time. The architecture calls for the aggregation of exploration assets in cislunar space prior to departure for Mars and utilizes high energy lunar-distant high Earth orbits for the final staging prior to departure. This paper presents the detailed analysis of various cislunar operations for the EMC Hybrid architecture as well as the result of the higher fidelity end-to-end trajectory analysis to understand the implications of the design choices on the Mars exploration campaign.

  7. Left Ventricular Assist Device End-to-End Connection to the Left Subclavian Artery: An Alternative Technique.

    PubMed

    Bortolussi, Giacomo; Lika, Alban; Bejko, Jonida; Gallo, Michele; Tarzia, Vincenzo; Gerosa, Gino; Bottio, Tomaso

    2015-10-01

    We describe a modified implantation technique for the HeartWare ventricular assist device. We access the apex through a left minithoracotomy. The outflow graft is tunneled through a small incision in the fourth intercostal space and then subcutaneously to the subclavian region. After division of the left axillary artery, an end-to-end anastomosis is performed to the proximal part, and the distal vessel is connected end-to-side through a fenestration in the outflow graft. We believe that this technique, particularly suitable for redo scenarios or severely calcified aorta, achieves a more direct blood flow into the aorta and reduces cerebrovascular events while avoiding excessive flow to the arm. PMID:26434488

  8. The MARS pathfinder end-to-end information system: A pathfinder for the development of future NASA planetary missions

    NASA Technical Reports Server (NTRS)

    Cook, Richard A.; Kazz, Greg J.; Tai, Wallace S.

    1996-01-01

    The development of the Mars pathfinder is considered with emphasis on the End-to-End Information System (EEIS) development approach. The primary mission objective is to successfully develop and deliver a single flight system to the Martian surface, demonstrating entry, descent and landing. The EEIS is a set of functions distributed throughout the flight, ground and Mission Operation Systems (MOS) that inter-operate in order to control, collect, transport, process, store and analyze the uplink and downlink information flows of the mission. Coherence between the mission systems is achieved though the EEIS architecture. The key characteristics of the system are: a concurrent engineering approach for the development of flight, ground and mission operation systems; the fundamental EEIS architectural heuristics; a phased incremental EEIS development and test approach, and an EEIS design deploying flight, ground and MOS operability features, including integrated ground and flight based toolsets.

  9. HITSZ_CDR: an end-to-end chemical and disease relation extraction system for BioCreative V.

    PubMed

    Li, Haodi; Tang, Buzhou; Chen, Qingcai; Chen, Kai; Wang, Xiaolong; Wang, Baohua; Wang, Zhe

    2016-01-01

    In this article, an end-to-end system was proposed for the challenge task of disease named entity recognition (DNER) and chemical-induced disease (CID) relation extraction in BioCreative V, where DNER includes disease mention recognition (DMR) and normalization (DN). Evaluation on the challenge corpus showed that our system achieved the highest F1-scores 86.93% on DMR, 84.11% on DN, 43.04% on CID relation extraction, respectively. The F1-score on DMR is higher than our previous one reported by the challenge organizers (86.76%), the highest F1-score of the challenge.Database URL: http://database.oxfordjournals.org/content/2016/baw077. PMID:27270713

  10. End-To-End Risk Assesment: From Genes and Protein to Acceptable Radiation Risks for Mars Exploration

    NASA Technical Reports Server (NTRS)

    Cucinotta, Francis A.; Schimmerling, Walter

    2000-01-01

    The human exploration of Mars will impose unavoidable health risks from galactic cosmic rays (GCR) and possibly solar particle events (SPE). It is the goal of NASA's Space Radiation Health Program to develop the capability to predict health risks with significant accuracy to ensure that risks are well below acceptable levels and to allow for mitigation approaches to be effective at reasonable costs. End-to-End risk assessment is the approach being followed to understand proton and heavy ion damage at the molecular, cellular, and tissue levels in order to predict the probability of the major health risk including cancer, neurological disorders, hereditary effects, cataracts, and acute radiation sickness and to develop countermeasures for mitigating risks.

  11. End-to-end stacking and liquid crystal condensation of 6- to 20-base pair DNA duplexes.

    SciTech Connect

    Nakata, M.; Zanchetta, G.; Chapman, B.D.; Christopher, D.; Jones, D.; Cross, J.O.; Pindak, R.; Bellini, T.; Noel, N.; X-Ray Science Division; Univ. of Colorado; Univ. di Milano; BNL

    2007-11-23

    Short complementary B-form DNA oligomers, 6 to 20 base pairs in length, are found to exhibit nematic and columnar liquid crystal phases, even though such duplexes lack the shape anisotropy required for liquid crystal ordering. Structural study shows that these phases are produced by the end-to-end adhesion and consequent stacking of the duplex oligomers into polydisperse anisotropic rod-shaped aggregates, which can order into liquid crystals. Upon cooling mixed solutions of short DNA oligomers, in which only a small fraction of the DNA present is complementary, the duplex-forming oligomers phase-separate into liquid crystal droplets, leaving the unpaired single strands in isotropic solution. In a chemical environment where oligomer ligation is possible, such ordering and condensation would provide an autocatalytic link whereby complementarity promotes the extended polymerization of complementary oligomers.

  12. The initial data products from the EUVE software - A photon's journey through the End-to-End System

    NASA Technical Reports Server (NTRS)

    Antia, Behram

    1993-01-01

    The End-to-End System (EES) is a unique collection of software modules created for use at the Center for EUV Astrophysics. The 'pipeline' is a shell script which executes selected EES modules and creates initial data products: skymaps, data sets for individual sources (called 'pigeonholes') and catalogs of sources. This article emphasizes the data from the all-sky survey, conducted between July 22, 1992 and January 21, 1993. A description of each of the major data products will be given and, as an example of how the pipeline works, the reader will follow a photon's path through the software pipeline into a pigeonhole. These data products are the primary goal of the EUVE all-sky survey mission, and so their relative importance for the follow-up science will also be discussed.

  13. Evaluation of Techniques to Detect Significant Network Performance Problems using End-to-End Active Network Measurements

    SciTech Connect

    Cottrell, R.Les; Logg, Connie; Chhaparia, Mahesh; Grigoriev, Maxim; Haro, Felipe; Nazir, Fawad; Sandford, Mark

    2006-01-25

    End-to-End fault and performance problems detection in wide area production networks is becoming increasingly hard as the complexity of the paths, the diversity of the performance, and dependency on the network increase. Several monitoring infrastructures are built to monitor different network metrics and collect monitoring information from thousands of hosts around the globe. Typically there are hundreds to thousands of time-series plots of network metrics which need to be looked at to identify network performance problems or anomalous variations in the traffic. Furthermore, most commercial products rely on a comparison with user configured static thresholds and often require access to SNMP-MIB information, to which a typical end-user does not usually have access. In our paper we propose new techniques to detect network performance problems proactively in close to realtime and we do not rely on static thresholds and SNMP-MIB information. We describe and compare the use of several different algorithms that we have implemented to detect persistent network problems using anomalous variations analysis in real end-to-end Internet performance measurements. We also provide methods and/or guidance for how to set the user settable parameters. The measurements are based on active probes running on 40 production network paths with bottlenecks varying from 0.5Mbits/s to 1000Mbit/s. For well behaved data (no missed measurements and no very large outliers) with small seasonal changes most algorithms identify similar events. We compare the algorithms' robustness with respect to false positives and missed events especially when there are large seasonal effects in the data. Our proposed techniques cover a wide variety of network paths and traffic patterns. We also discuss the applicability of the algorithms in terms of their intuitiveness, their speed of execution as implemented, and areas of applicability. Our encouraging results compare and evaluate the accuracy of our detection

  14. End-to-End Information System design at the NASA Jet Propulsion Laboratory. [data transmission between user and space-based sensor

    NASA Technical Reports Server (NTRS)

    Hooke, A. J.

    1978-01-01

    In recognition of a pressing need of the 1980s to optimize the two-way flow of information between a ground-based user and a remote-space-based sensor, an end-to-end approach to the design of information systems has been adopted at the JPL. This paper reviews End-to-End Information System (EEIS) activity at the JPL, with attention given to the scope of the EEIS transfer function, and functional and physical elements of the EEIS. The relationship between the EEIS and the NASA End-to-End Data System program is discussed.

  15. End-to-end Cyberinfrastructure and Data Services for Earth System Science Education and Research: Unidata's Plans and Directions

    NASA Astrophysics Data System (ADS)

    Ramamurthy, M.

    2005-12-01

    work together in a fundamentally different way. Likewise, the advent of digital libraries, grid computing platforms, interoperable frameworks, standards and protocols, open-source software, and community atmospheric models have been important drivers in shaping the use of a new generation of end-to-end cyberinfrastructure for solving some of the most challenging scientific and educational problems. In this talk, I will present an overview of the scientific, technological, and educational drivers and discuss recent developments in cyberinfrastructure and Unidata's role and directions in providing robust, end-to-end data services for solving geoscientific problems and advancing student learning.

  16. End-to-end Cyberinfrastructure and Data Services for Earth System Science Education and Research: A vision for the future

    NASA Astrophysics Data System (ADS)

    Ramamurthy, M. K.

    2006-05-01

    yet revolutionary way of building applications and methods to connect and exchange information over the Web. This new approach, based on XML - a widely accepted format for exchanging data and corresponding semantics over the Internet - enables applications, computer systems, and information processes to work together in fundamentally different ways. Likewise, the advent of digital libraries, grid computing platforms, interoperable frameworks, standards and protocols, open-source software, and community atmospheric models have been important drivers in shaping the use of a new generation of end-to-end cyberinfrastructure for solving some of the most challenging scientific and educational problems. In this talk, I will present an overview of the scientific, technological, and educational landscape, discuss recent developments in cyberinfrastructure, and Unidata's role in and vision for providing easy-to use, robust, end-to-end data services for solving geoscientific problems and advancing student learning.

  17. Reconstruction of the primordial power spectrum from CMB data

    SciTech Connect

    Guo, Zong-Kuan; Zhang, Yuan-Zhong; Schwarz, Dominik J. E-mail: dschwarz@physik.uni-bielefeld.de

    2011-08-01

    Measuring the deviation from scale invariance of the primordial power spectrum is a critical test of inflation. In this paper we reconstruct the shape of the primordial power spectrum of curvature perturbations from the cosmic microwave background data, including the 7-year Wilkinson Microwave Anisotropy Probe data and the Atacama Cosmology Telescope 148 GHz data, by using a binning method of a cubic spline interpolation in log-log space. We find that the power-law spectrum is preferred by the data and that the Harrison-Zel'dovich spectrum is disfavored at 95% confidence level. These conclusions hold with and without allowing for tensor modes, however the simpler model without tensors is preferred by the data. We do not find evidence for a feature in the primordial power spectrum — in full agreement with generic predictions from cosmological inflation.

  18. An anthropomorphic multimodality (CT/MRI) head phantom prototype for end-to-end tests in ion radiotherapy.

    PubMed

    Gallas, Raya R; Hünemohr, Nora; Runz, Armin; Niebuhr, Nina I; Jäkel, Oliver; Greilich, Steffen

    2015-12-01

    With the increasing complexity of external beam therapy "end-to-end" tests are intended to cover every step from therapy planning through to follow-up in order to fulfill the higher demands on quality assurance. As magnetic resonance imaging (MRI) has become an important part of the treatment process, established phantoms such as the Alderson head cannot fully be used for those tests and novel phantoms have to be developed. Here, we present a feasibility study of a customizable multimodality head phantom. It is initially intended for ion radiotherapy but may also be used in photon therapy. As basis for the anthropomorphic head shape we have used a set of patient computed tomography (CT) images. The phantom recipient consisting of epoxy resin was produced by using a 3D printer. It includes a nasal air cavity, a cranial bone surrogate (based on dipotassium phosphate), a brain surrogate (based on agarose gel), and a surrogate for cerebrospinal fluid (based on distilled water). Furthermore, a volume filled with normoxic dosimetric gel mimicked a tumor. The entire workflow of a proton therapy could be successfully applied to the phantom. CT measurements revealed CT numbers agreeing with reference values for all surrogates in the range from 2 HU to 978 HU (120 kV). MRI showed the desired contrasts between the different phantom materials especially in T2-weighted images (except for the bone surrogate). T2-weighted readout of the polymerization gel dosimeter allowed approximate range verification. PMID:26189015

  19. Hardware and Methods of the Optical End-to-End Test of the Far Ultraviolet Spectroscopic Explorer (FUSE)

    NASA Technical Reports Server (NTRS)

    Conard, Steven J.; Redman, Kevin W.; Barkhouser, Robert H.; McGuffey, Doug B.; Smee, Stephen; Ohl, Raymond G.; Kushner, Gary

    1999-01-01

    The Far Ultraviolet Spectroscopic Explorer (FUSE), currently being tested and scheduled for a 1999 launch, is an astrophysics satellite designed to provide high spectral resolving power (Lambda/(Delta)Lambda = 24,000-30,000) over the interval 90.5-118.7 nm. The FUSE optical path consists of four co-aligned, normal incidence, off-axis parabolic, primary mirrors which illuminate separate Rowland circle spectrograph channels equipped with holographic gratings and delay line microchannel plate detectors. We describe the hardware and methods used for the optical end-to-end test of the FUSE instrument during satellite integration and test. Cost and schedule constraints forced us to devise a simplified version of the planned optical test which occurred in parallel with satellite thermal-vacuum testing. The optical test employed a collimator assembly which consisted of four co-aligned, 15" Cassegrain telescopes which were positioned above the FUSE instrument, providing a collimated beam for each optical channel. A windowed UV light source, remotely adjustable in three axes, was mounted at the focal plane of each collimator. Problems with the UV light sources, including high F-number and window failures, were the only major difficulties encountered during the test. The test succeeded in uncovering a significant problem with the secondary structure used for the instrument closeout cavity and, furthermore, showed that the mechanical solution was successful. The hardware was also used extensively for simulations of science observations, providing both UV light for spectra and visible light for the fine error sensor camera.

  20. A novel end-to-end fault detection and localization protocol for wavelength-routed WDM networks

    NASA Astrophysics Data System (ADS)

    Zeng, Hongqing; Vukovic, Alex; Huang, Changcheng

    2005-09-01

    Recently the wavelength division multiplexing (WDM) networks are becoming prevalent for telecommunication networks. However, even a very short disruption of service caused by network faults may lead to high data loss in such networks due to the high date rates, increased wavelength numbers and density. Therefore, the network survivability is critical and has been intensively studied, where fault detection and localization is the vital part but has received disproportional attentions. In this paper we describe and analyze an end-to-end lightpath fault detection scheme in data plane with the fault notification in control plane. The endeavor is focused on reducing the fault detection time. In this protocol, the source node of each lightpath keeps sending hello packets to the destination node exactly following the path for data traffic. The destination node generates an alarm once a certain number of consecutive hello packets are missed within a given time period. Then the network management unit collects all alarms and locates the faulty source based on the network topology, as well as sends fault notification messages via control plane to either the source node or all upstream nodes along the lightpath. The performance evaluation shows such a protocol can achieve fast fault detection, and at the same time, the overhead brought to the user data by hello packets is negligible.

  1. Objective end-to-end (mouth-to-ear) conversational speech quality tests for VoIP scenarios

    NASA Astrophysics Data System (ADS)

    Kettler, Frank; Gierlich, Hans W.

    2001-07-01

    From the speech quality point of view the differentiation between terminals and network in communications over IP is no longer possible. Consequently the overall speech quality assessment has to take this into account and requires end-to-end tests. Suitable test setups including the terminals acoustics using artificial head technology as a close to reality interface are introduced. In a second part the influence of various subjectively relevant parameters on speech quality is discussed. Correlated objec-tive parameters like delay, echo, double talk capability, listening speech quality and parameters determining background noise transmission quality are described. Appropriate analysis methods are given. The discussion points out the influence of delay on conversation dynamics impairments and its influence on echo perception, because the expected delay in VoIP sce-narios is probably higher than typically recommended for telephone conversations. Optimization criteria are introduced for implemented echo cancellers as well as test methods to assess the one-way speech sound quality, double talk performance and background noise transmission.

  2. End-to-end simulation of high-contrast imaging systems: methods and results for the PICTURE mission family

    NASA Astrophysics Data System (ADS)

    Douglas, Ewan S.; Hewasawam, Kuravi; Mendillo, Christopher B.; Cahoy, Kerri L.; Cook, Timothy A.; Finn, Susanna C.; Howe, Glenn A.; Kuchner, Marc J.; Lewis, Nikole K.; Marinan, Anne D.; Mawet, Dimitri; Chakrabarti, Supriya

    2015-09-01

    We describe a set of numerical approaches to modeling the performance of space flight high-contrast imaging payloads. Mission design for high-contrast imaging requires numerical wavefront error propagation to ensure accurate component specifications. For constructed instruments, wavelength and angle-dependent throughput and contrast models allow detailed simulations of science observations, allowing mission planners to select the most productive science targets. The PICTURE family of missions seek to quantify the optical brightness of scattered light from extrasolar debris disks via several high-contrast imaging techniques: sounding rocket (the Planet Imaging Concept Testbed Using a Rocket Experiment) and balloon flights of a visible nulling coronagraph, as well as a balloon flight of a vector vortex coronagraph (the Planetary Imaging Concept Testbed Using a Recoverable Experiment - Coronagraph, PICTURE-C). The rocket mission employs an on-axis 0.5m Gregorian telescope, while the balloon flights will share an unobstructed off-axis 0.6m Gregorian. This work details the flexible approach to polychromatic, end-to-end physical optics simulations used for both the balloon vector vortex coronagraph and rocket visible nulling coronagraph missions. We show the preliminary PICTURE-C telescope and vector vortex coronagraph design will achieve 10-8 contrast without post-processing as limited by realistic optics, but not considering polarization or low-order errors. Simulated science observations of the predicted warm ring around Epsilon Eridani illustrate the performance of both missions.

  3. WARP (workflow for automated and rapid production): a framework for end-to-end automated digital print workflows

    NASA Astrophysics Data System (ADS)

    Joshi, Parag

    2006-02-01

    Publishing industry is experiencing a major paradigm shift with the advent of digital publishing technologies. A large number of components in the publishing and print production workflow are transformed in this shift. However, the process as a whole requires a great deal of human intervention for decision making and for resolving exceptions during job execution. Furthermore, a majority of the best-of-breed applications for publishing and print production are intrinsically designed and developed to be driven by humans. Thus, the human-intensive nature of the current prepress process accounts for a very significant amount of the overhead costs in fulfillment of jobs on press. It is a challenge to automate the functionality of applications built with the model of human driven exectution. Another challenge is to orchestrate various components in the publishing and print production pipeline such that they work in a seamless manner to enable the system to perform automatic detection of potential failures and take corrective actions in a proactive manner. Thus, there is a great need for a coherent and unifying workflow architecture that streamlines the process and automates it as a whole in order to create an end-to-end digital automated print production workflow that does not involve any human intervention. This paper describes an architecture and building blocks that lay the foundation for a plurality of automated print production workflows.

  4. Results from solar reflective band end-to-end testing for VIIRS F1 sensor using T-SIRCUS

    NASA Astrophysics Data System (ADS)

    McIntire, Jeff; Moyer, David; McCarthy, James K.; Brown, Steven W.; Lykke, Keith R.; De Luccia, Frank; Xiong, Xiaoxiong; Butler, James J.; Guenther, Bruce

    2011-10-01

    Verification of the Visible Infrared Imager Radiometer Suite (VIIRS) End-to-End (E2E) sensor calibration is highly recommended before launch, to identify any anomalies and to improve our understanding of the sensor onorbit calibration performance. E2E testing of the Reflective Solar Bands (RSB) calibration cycle was performed pre-launch for the VIIRS Flight 1 (F1) sensor at the Ball Aerospace facility in Boulder CO in March 2010. VIIRS reflective band calibration cycle is very similar to heritage sensor MODIS in that solar illumination, via a diffuser, is used to correct for temporal variations in the instrument responsivity. Monochromatic light from the NIST T-SIRCUS (Traveling Spectral Irradiance and Radiance Responsivity Calibrations using Uniform Sources) was used to illuminate both the Earth View (EV), via an integrating sphere, and the Solar Diffuser (SD) view, through a collimator. The collimator illumination was cycled through a series of angles intended to simulate the range of possible angles for which solar radiation will be incident on the solar attenuation screen on-orbit. Ideally, the measured instrument responsivity (defined here as the ratio of the detector response to the at-sensor radiance) should be the same whether the EV or SD view is illuminated. The ratio of the measured responsivities was determined at each collimator angle and wavelength. In addition, the Solar Diffuser Stability Monitor (SDSM), a ratioing radiometer designed to track the temporal variation in the SD Bidirectional Reflectance Factor (BRF) by direct comparison to solar radiation, was illuminated by the collimator. The measured SDSM ratio was compared to the predicted ratio. An uncertainty analysis was also performed on both the SD and SDSM calibrations.

  5. An unusual structural motif of antimicrobial peptides containing end-to-end macrocycle and cystine-knot disulfides.

    PubMed

    Tam, J P; Lu, Y A; Yang, J L; Chiu, K W

    1999-08-01

    Four macrocyclic cystine-knot peptides of 29-31 residues, kalata, circulin A and B (CirA and CirB), and cyclopsychotride, have been isolated from coffee plants but have undetermined physiological functions. These macrocycles and 10 of their analogs prepared by chemical synthesis were tested against nine strains of microbes. Kalata and CirA were specific for the Gram-positive Staphylococcus aureus with a minimum inhibition concentration of approximately 0.2 microM. They were relatively ineffective against Gram-negative bacteria such as Escherichia coli and Pseudomonas aeruginosa. However, CirB and cyclopsychotride were active against both Gram-positive and Gram-negative bacteria. In particular, CirB showed potent activity against E. coli with a minimum inhibitory concentration of 0.41 microM. All four cyclic peptides were moderately active against two strains of fungi, Candida kefyr and Candida tropicalis, but were inactive against Candida albicans. These macrocycles are cytotoxic and lysed human red blood cell with a lethal dose 50% of 400 microM. Modifying the Arg residue in kalata with a keto aldehyde significantly reduced its activity against S. aureus whereas blocking the arg in CirA produced no significant effect. The two-disulfide variants and their scrambled disulfide isomers exhibited antimicrobial profiles and potency similar to their native peptides. However, in high-salt assays (100 mM NaCl), few of these macrocyclic peptides, natives or analogs, retained antimicrobial activity. These results show that the macrocyclic peptides possess specific and potent antimicrobial activity that is salt-dependent and that their initial interactions with the microbial surfaces may be electrostatic, an effect commonly found in defensin antimicrobial peptides. Furthermore, their end-to-end cyclic structure with a cystine-knot motif represents a molecular structure of antimicrobials and may provide a useful template for the design of novel peptide antibiotics. PMID

  6. End-to-end gene fusions and their impact on the production of multifunctional biomass degrading enzymes

    SciTech Connect

    Rizk, Mazen; Antranikian, Garabed; Elleuche, Skander

    2012-11-09

    Highlights: Black-Right-Pointing-Pointer Multifunctional enzymes offer an interesting approach for biomass degradation. Black-Right-Pointing-Pointer Size and conformation of separate constructs play a role in the effectiveness of chimeras. Black-Right-Pointing-Pointer A connecting linker allows for maximal flexibility and increased thermostability. Black-Right-Pointing-Pointer Genes with functional similarities are the best choice for fusion candidates. -- Abstract: The reduction of fossil fuels, coupled with its increase in price, has made the search for alternative energy resources more plausible. One of the topics gaining fast interest is the utilization of lignocellulose, the main component of plants. Its primary constituents, cellulose and hemicellulose, can be degraded by a series of enzymes present in microorganisms, into simple sugars, later used for bioethanol production. Thermophilic bacteria have proven to be an interesting source of enzymes required for hydrolysis since they can withstand high and denaturing temperatures, which are usually required for processes involving biomass degradation. However, the cost associated with the whole enzymatic process is staggering. A solution for cost effective and highly active production is through the construction of multifunctional enzyme complexes harboring the function of more than one enzyme needed for the hydrolysis process. There are various strategies for the degradation of complex biomass ranging from the regulation of the enzymes involved, to cellulosomes, and proteins harboring more than one enzymatic activity. In this review, the construction of multifunctional biomass degrading enzymes through end-to-end gene fusions, and its impact on production and activity by choosing the enzymes and linkers is assessed.

  7. End-to-end sensor simulation for spectral band selection and optimization with application to the Sentinel-2 mission.

    PubMed

    Segl, Karl; Richter, Rudolf; Küster, Theres; Kaufmann, Hermann

    2012-02-01

    An end-to-end sensor simulation is a proper tool for the prediction of the sensor's performance over a range of conditions that cannot be easily measured. In this study, such a tool has been developed that enables the assessment of the optimum spectral resolution configuration of a sensor based on key applications. It employs the spectral molecular absorption and scattering properties of materials that are used for the identification and determination of the abundances of surface and atmospheric constituents and their interdependence on spatial resolution and signal-to-noise ratio as a basis for the detailed design and consolidation of spectral bands for the future Sentinel-2 sensor. The developed tools allow the computation of synthetic Sentinel-2 spectra that form the frame for the subsequent twofold analysis of bands in the atmospheric absorption and window regions. One part of the study comprises the assessment of optimal spatial and spectral resolution configurations for those bands used for atmospheric correction, optimized with regard to the retrieval of aerosols, water vapor, and the detection of cirrus clouds. The second part of the study presents the optimization of thematic bands, mainly driven by the spectral characteristics of vegetation constituents and minerals. The investigation is performed for different wavelength ranges because most remote sensing applications require the use of specific band combinations rather than single bands. The results from the important "red-edge" and the "short-wave infrared" domains are presented. The recommended optimum spectral design predominantly confirms the sensor parameters given by the European Space Agency. The system is capable of retrieving atmospheric and geobiophysical parameters with enhanced quality compared to existing multispectral sensors. Minor spectral changes of single bands are discussed in the context of typical remote sensing applications, supplemented by the recommendation of a few new bands for

  8. Results from Solar Reflective Band End-to-End Testing for VIIRS F1 Sensor Using T-SIRCUS

    NASA Technical Reports Server (NTRS)

    McIntire, Jeff; Moyer, David; McCarthy, James K.; DeLuccia, Frank; Xiong, Xiaoxiong; Butler, James J.; Guenther, Bruce

    2011-01-01

    Verification of the Visible Infrared Imager Radiometer Suite (VIIRS) End-to-End (E2E) sensor calibration is highly recommended before launch, to identify any anomalies and to improve our understanding of the sensor on-orbit calibration performance. E2E testing of the Reflective Solar Bands (RSB) calibration cycle was performed pre-launch for the VIIRS Fight 1 (F1) sensor at the Ball Aerospace facility in Boulder CO in March 2010. VIIRS reflective band calibration cycle is very similar to heritage sensor MODIS in that solar illumination, via a diffuser, is used to correct for temporal variations in the instrument responsivity. Monochromatic light from the NIST T-SIRCUS was used to illuminate both the Earth View (EV), via an integrating sphere, and the Solar Diffuser (SD) view, through a collimator. The collimator illumination was cycled through a series of angles intended to simulate the range of possible angles for which solar radiation will be incident on the solar attenuation screen on-orbit. Ideally, the measured instrument responsivity (defined here as the ratio of the detector response to the at-sensor radiance) should be the same whether the EV or SD view is illuminated. The ratio of the measured responsivities was determined at each collimator angle and wavelength. In addition, the Solar Diffuser Stability Monitor (SDSM), a ratioing radiometer designed to track the temporal variation in the SD BRF by direct comparison to solar radiation, was illuminated by the collimator. The measured SDSM ratio was compared to the predicted ratio. An uncertainty analysis was also performed on both the SD and SDSM calibrations.

  9. Computational simulation of flow in the end-to-end anastomosis of a rigid graft and a compliant artery.

    PubMed

    Qiu, Y; Tarbell, J M

    1996-01-01

    Implanted vascular grafts often fail because of the development of intimal hyperplasia in the anastomotic region, and compliance mismatch between the host artery and graft exacerbates the problem. This study focused on the effects of radial artery wall motion and phase angle between pressure and flow waves (impedance phase angle [IPA]) on the wall shear rate (WSR) behavior near end-to-end vascular graft anastomoses models connecting rigid grafts and compliant arteries. A finite element model with transient flow and moving boundaries was set up to simulate oscillatory flow through a 16% undersized (mean) diameter graft model. During the simulations, different artery diameter variations (DVs) over a cycle (DV) and IPAs were simulated in the physiologic range for an oscillatory flow (mean Re = 150, peak Re = 300, unsteadiness parameter alpha = 3.9). The results show that for normal physiologic conditions (DV = 6%, IPA = -45 degrees) in a 16% undersized graft, the minimum distal mean WSR is reduced by 60% compared to steady flow at the mean Re; the minimum distal WSR amplitude increases 50% when IPA changes from -5 degrees to -85 degrees, and increases 60% when DV changes from 2% to 10%. This indicates that compliance mismatch induces lower mean WSR and more oscillatory WSR in the distal anastomotic region, which may contribute to intimal hyperplasia. In addition, the convergent-divergent geometry of the 16% undersized graft model can significantly affect the force pattern applied to the local endothelial cell layer near the anastomosis by altering the local phase angle between the flow induced tangential force (synchronous with WSR) and the radial artery expansion induced cyclic hoop strain (synchronous with DV). This local phase angle is decreased by 65 degrees in the distal divergent geometry, while increased by 15 degrees in the proximal convergent geometry. PMID:8944971

  10. Designing an End-to-End System for Data Storage, Analysis, and Visualization for an Urban Environmental Observatory

    NASA Astrophysics Data System (ADS)

    McGuire, M. P.; Welty, C.; Gangopadhyay, A.; Karabatis, G.; Chen, Z.

    2006-05-01

    The urban environment is formed by complex interactions between natural and human dominated systems, the study of which requires the collection and analysis of very large datasets that span many disciplines. Recent advances in sensor technology and automated data collection have improved the ability to monitor urban environmental systems and are making the idea of an urban environmental observatory a reality. This in turn has created a number of potential challenges in data management and analysis. We present the design of an end-to-end system to store, analyze, and visualize data from a prototype urban environmental observatory based at the Baltimore Ecosystem Study, a National Science Foundation Long Term Ecological Research site (BES LTER). We first present an object-relational design of an operational database to store high resolution spatial datasets as well as data from sensor networks, archived data from the BES LTER, data from external sources such as USGS NWIS, EPA Storet, and metadata. The second component of the system design includes a spatiotemporal data warehouse consisting of a data staging plan and a multidimensional data model designed for the spatiotemporal analysis of monitoring data. The system design also includes applications for multi-resolution exploratory data analysis, multi-resolution data mining, and spatiotemporal visualization based on the spatiotemporal data warehouse. Also the system design includes interfaces with water quality models such as HSPF, SWMM, and SWAT, and applications for real-time sensor network visualization, data discovery, data download, QA/QC, and backup and recovery, all of which are based on the operational database. The system design includes both internet and workstation-based interfaces. Finally we present the design of a laboratory for spatiotemporal analysis and visualization as well as real-time monitoring of the sensor network.

  11. Fast dictionary-based reconstruction for diffusion spectrum imaging.

    PubMed

    Bilgic, Berkin; Chatnuntawech, Itthi; Setsompop, Kawin; Cauley, Stephen F; Yendiki, Anastasia; Wald, Lawrence L; Adalsteinsson, Elfar

    2013-11-01

    Diffusion spectrum imaging reveals detailed local diffusion properties at the expense of substantially long imaging times. It is possible to accelerate acquisition by undersampling in q-space, followed by image reconstruction that exploits prior knowledge on the diffusion probability density functions (pdfs). Previously proposed methods impose this prior in the form of sparsity under wavelet and total variation transforms, or under adaptive dictionaries that are trained on example datasets to maximize the sparsity of the representation. These compressed sensing (CS) methods require full-brain processing times on the order of hours using MATLAB running on a workstation. This work presents two dictionary-based reconstruction techniques that use analytical solutions, and are two orders of magnitude faster than the previously proposed dictionary-based CS approach. The first method generates a dictionary from the training data using principal component analysis (PCA), and performs the reconstruction in the PCA space. The second proposed method applies reconstruction using pseudoinverse with Tikhonov regularization with respect to a dictionary. This dictionary can either be obtained using the K-SVD algorithm, or it can simply be the training dataset of pdfs without any training. All of the proposed methods achieve reconstruction times on the order of seconds per imaging slice, and have reconstruction quality comparable to that of dictionary-based CS algorithm. PMID:23846466

  12. Pre-Launch End-to-End Testing Plans for the SPAce Readiness Coherent Lidar Experiment (SPARCLE)

    NASA Technical Reports Server (NTRS)

    Kavaya, Michael J.

    1999-01-01

    The SPAce Readiness Coherent Lidar Experiment (SPARCLE) mission was proposed as a low cost technology demonstration mission, using a 2-micron, 100-mJ, 6-Hz, 25-cm, coherent lidar system based on demonstrated technology. SPARCLE was selected in late October 1997 to be NASA's New Millennium Program (NMP) second earth-observing (EO-2) mission. To maximize the success probability of SPARCLE, NASA/MSFC desired expert guidance in the areas of coherent laser radar (CLR) theory, CLR wind measurement, fielding of CLR systems, CLR alignment validation, and space lidar experience. This led to the formation of the NASA/MSFC Coherent Lidar Technology Advisory Team (CLTAT) in December 1997. A threefold purpose for the advisory team was identified as: 1) guidance to the SPARCLE mission, 2) advice regarding the roadmap of post-SPARCLE coherent Doppler wind lidar (CDWL) space missions and the desired matching technology development plan 3, and 3) general coherent lidar theory, simulation, hardware, and experiment information exchange. The current membership of the CLTAT is shown. Membership does not result in any NASA or other funding at this time. We envision the business of the CLTAT to be conducted mostly by email, teleconference, and occasional meetings. The three meetings of the CLTAT to date, in Jan. 1998, July 1998, and Jan. 1999, have all been collocated with previously scheduled meetings of the Working Group on Space-Based Lidar Winds. The meetings have been very productive. Topics discussed include the SPARCLE technology validation plan including pre-launch end-to-end testing, the space-based wind mission roadmap beyond SPARCLE and its implications on the resultant technology development, the current values and proposed future advancement in lidar system efficiency, and the difference between using single-mode fiber optical mixing vs. the traditional free space optical mixing. attitude information from lidar and non-lidar sensors, and pointing knowledge algorithms will

  13. Volumetric-Modulated Arc Therapy: Effective and Efficient End-to-End Patient-Specific Quality Assurance

    SciTech Connect

    O'Daniel, Jennifer; Das, Shiva; Wu, Q. Jackie; Yin Fangfang

    2012-04-01

    Purpose: To explore an effective and efficient end-to-end patient-specific quality-assurance (QA) protocol for volumetric modulated arc radiotherapy (VMAT) and to evaluate the suitability of a stationary radiotherapy QA device (two-dimensional [2D] ion chamber array) for VMAT QA. Methods and Materials: Three methods were used to analyze 39 VMAT treatment plans for brain, spine, and prostate: ion chamber (one-dimensional absolute, n = 39), film (2D relative, coronal/sagittal, n = 8), and 2D ion chamber array (ICA, 2D absolute, coronal/sagittal, n = 39) measurements. All measurements were compared with the treatment planning system dose calculation either via gamma analysis (3%, 3- to 4-mm distance-to-agreement criteria) or absolute point dose comparison. The film and ion chamber results were similarly compared with the ICA measurements. Results: Absolute point dose measurements agreed well with treatment planning system computed doses (ion chamber: median deviation, 1.2%, range, -0.6% to 3.3%; ICA: median deviation, 0.6%, range, -1.8% to 2.9%). The relative 2D dose measurements also showed good agreement with computed doses (>93% of pixels in all films passing gamma, >90% of pixels in all ICA measurements passing gamma). The ICA relative dose results were highly similar to those of film (>90% of pixels passing gamma). The coronal and sagittal ICA measurements were statistically indistinguishable by the paired t test with a hypothesized mean difference of 0.1%. The ion chamber and ICA absolute dose measurements showed a similar trend but had disparities of 2-3% in 18% of plans. Conclusions: After validating the new VMAT implementation with ion chamber, film, and ICA, we were able to maintain an effective yet efficient patient-specific VMAT QA protocol by reducing from five (ion chamber, film, and ICA) to two measurements (ion chamber and single ICA) per plan. The ICA (Matrixx Registered-Sign , IBA Dosimetry) was validated for VMAT QA, but ion chamber measurements are

  14. The End-To-End Safety Verification Process Implemented to Ensure Safe Operations of the Columbus Research Module

    NASA Astrophysics Data System (ADS)

    Arndt, J.; Kreimer, J.

    2010-09-01

    The European Space Laboratory COLUMBUS was launched in February 2008 with NASA Space Shuttle Atlantis. Since successful docking and activation this manned laboratory forms part of the International Space Station(ISS). Depending on the objectives of the Mission Increments the on-orbit configuration of the COLUMBUS Module varies with each increment. This paper describes the end-to-end verification which has been implemented to ensure safe operations under the condition of a changing on-orbit configuration. That verification process has to cover not only the configuration changes as foreseen by the Mission Increment planning but also those configuration changes on short notice which become necessary due to near real-time requests initiated by crew or Flight Control, and changes - most challenging since unpredictable - due to on-orbit anomalies. Subject of the safety verification is on one hand the on orbit configuration itself including the hardware and software products, on the other hand the related Ground facilities needed for commanding of and communication to the on-orbit System. But also the operational products, e.g. the procedures prepared for crew and ground control in accordance to increment planning, are subject of the overall safety verification. In order to analyse the on-orbit configuration for potential hazards and to verify the implementation of the related Safety required hazard controls, a hierarchical approach is applied. The key element of the analytical safety integration of the whole COLUMBUS Payload Complement including hardware owned by International Partners is the Integrated Experiment Hazard Assessment(IEHA). The IEHA especially identifies those hazardous scenarios which could potentially arise through physical and operational interaction of experiments. A major challenge is the implementation of a Safety process which owns quite some rigidity in order to provide reliable verification of on-board Safety and which likewise provides enough

  15. SBSS Demonstrator: A design for efficient demonstration of Space-based Space Surveillance end-to-end capabilities

    NASA Astrophysics Data System (ADS)

    Utzmann, Jens; Flohrer, Tim; Schildknecht, Thomas; Wagner, Axel; Silha, Jiri; Willemsen, Philip; Teston, Frederic

    This paper presents the capabilities of a Space-Based Space Surveillance (SBSS) demonstration mission for Space Surveillance and Tracking (SST) based on a micro-satellite platform. The results have been produced in the frame of ESA’s "Assessment Study for Space Based Space Surveillance Demonstration Mission" performed by the Airbus Defence and Space consortium. Space Surveillance and Tracking is part of Space Situational Awareness (SSA) and covers the detection, tracking and cataloguing of space debris and satellites. Derived SST services comprise a catalogue of these man-made objects, collision warning, detection and characterisation of in-orbit fragmentations, sub-catalogue debris characterisation, etc. The assessment of SBSS in a SST system architecture has shown that both an operational SBSS and also already a well-designed space-based demonstrator can provide substantial performance in terms of surveillance and tracking of beyond-LEO objects. Especially the early deployment of a demonstrator, possible by using standard equipment, could boost initial operating capability and create a self-maintained object catalogue. Furthermore, unique statistical information about small-size LEO debris (mm size) can be collected in-situ. Unlike classical technology demonstration missions, the primary goal is the demonstration and optimisation of the functional elements in a complex end-to-end chain (mission planning, observation strategies, data acquisition, processing and fusion, etc.) until the final products can be offered to the users. Also past and current missions by the US (SBV, SBSS) and Canada (Sapphire, NEOSSat) underline the advantages of space-based space surveillance. The presented SBSS system concept takes the ESA SST System Requirements (derived within the ESA SSA Preparatory Program) into account and aims at fulfilling SST core requirements in a stand-alone manner. Additionally, requirments for detection and characterisation of small-sized LEO debris are

  16. WE-G-BRD-08: End-To-End Targeting Accuracy of the Gamma Knife for Trigeminal Neuralgia

    SciTech Connect

    Brezovich, I; Wu, X; Duan, J; Benhabib, S; Huang, M; Shen, S; Cardan, R; Popple, R

    2014-06-15

    Purpose: Current QA procedures verify accuracy of individual equipment parameters, but may not include CT and MRI localizers. This study uses an end-to-end approach to measure the overall targeting errors in individual patients previously treated for trigeminal neuralgia. Methods: The trigeminal nerve is simulated by a 3 mm long, 3.175 mm (1/8 inch) diameter MRI contrast-filled cavity embedded within a PMMA plastic capsule. The capsule is positioned within the head frame such that the cavity position matches the Gamma Knife coordinates of 10 previously treated patients. Gafchromic EBT2 film is placed at the center of the cavity in coronal and sagittal orientations. The films are marked with a pin prick to identify the cavity center. Treatments are planned for delivery with 4 mm collimators using MRI and CT scans acquired with the clinical localizer boxes and acquisition protocols. Coordinates of shots are chosen so that the cavity is centered within the 50% isodose volume. Following irradiation, the films are scanned and analyzed. Targeting errors are defined as the distance between the pin prick and the centroid of the 50% isodose line. Results: Averaged over 10 patient simulations, targeting errors along the x, y and z coordinates (patient left-to-right, posterior-anterior, head-to-foot) were, respectively, −0.060 +/− 0.363, −0.350 +/− 0.253, and 0.364 +/− 0.191 mm when MRI was used for treatment planning. Planning according to CT exhibited generally smaller errors, namely 0.109 +/− 0.167, −0.191 +/− 0.144, and 0.211 +/− 0.94 mm. The largest errors in MRI and CT planned treatments were, respectively, y = −0.761 and x = 0.428 mm. Conclusion: Unless patient motion or stronger MRI image distortion in actual treatments caused additional errors, all patients received the prescribed dose, i.e., the targeted section of the trig±eminal nerve was contained within the 50% isodose surface in all cases.

  17. Reconstructing Face Image from the Thermal Infrared Spectrum to the Visible Spectrum.

    PubMed

    Kresnaraman, Brahmastro; Deguchi, Daisuke; Takahashi, Tomokazu; Mekada, Yoshito; Ide, Ichiro; Murase, Hiroshi

    2016-01-01

    During the night or in poorly lit areas, thermal cameras are a better choice instead of normal cameras for security surveillance because they do not rely on illumination. A thermal camera is able to detect a person within its view, but identification from only thermal information is not an easy task. The purpose of this paper is to reconstruct the face image of a person from the thermal spectrum to the visible spectrum. After the reconstruction, further image processing can be employed, including identification/recognition. Concretely, we propose a two-step thermal-to-visible-spectrum reconstruction method based on Canonical Correlation Analysis (CCA). The reconstruction is done by utilizing the relationship between images in both thermal infrared and visible spectra obtained by CCA. The whole image is processed in the first step while the second step processes patches in an image. Results show that the proposed method gives satisfying results with the two-step approach and outperforms comparative methods in both quality and recognition evaluations. PMID:27110781

  18. Reconstructing Face Image from the Thermal Infrared Spectrum to the Visible Spectrum

    PubMed Central

    Kresnaraman, Brahmastro; Deguchi, Daisuke; Takahashi, Tomokazu; Mekada, Yoshito; Ide, Ichiro; Murase, Hiroshi

    2016-01-01

    During the night or in poorly lit areas, thermal cameras are a better choice instead of normal cameras for security surveillance because they do not rely on illumination. A thermal camera is able to detect a person within its view, but identification from only thermal information is not an easy task. The purpose of this paper is to reconstruct the face image of a person from the thermal spectrum to the visible spectrum. After the reconstruction, further image processing can be employed, including identification/recognition. Concretely, we propose a two-step thermal-to-visible-spectrum reconstruction method based on Canonical Correlation Analysis (CCA). The reconstruction is done by utilizing the relationship between images in both thermal infrared and visible spectra obtained by CCA. The whole image is processed in the first step while the second step processes patches in an image. Results show that the proposed method gives satisfying results with the two-step approach and outperforms comparative methods in both quality and recognition evaluations. PMID:27110781

  19. Reconstruction of Rain Microstructure From Spectrum of Scattering Light

    NASA Astrophysics Data System (ADS)

    Sterlyadkin, V.; Gluschenko, A.

    Night photoregistration of light, scattered by drops had proved that practically all drops oscillate as they fall. As drop oscillation frequency W monotony diminish with drop volume V rise, so different fractions of rain form different parts of spectrum. Thereby it is possible to reconstruct rain microstructure from remote optical measure- ments. In common case the form of spectrum depends not only on drop size distri- bution N(V) but also on oscillation amplitudes function, scattering phase function for oscillating drops and on frequency dependence W(V). The statistical treatment of our field data had shown that average oscillation amplitude rise with drop volume V as , where A is a some constant. This result allows to solve the inverse problem: to re- construct drop size distribution N(V) from the power spectrum of light, scattering by rain. Scattering phase function for nonspherical and oscillating drops was calculated in straight-line approximation. Analysis of optical properties of oscillating water drop had shown some optimal measurement geometry for registration of rain microstruc- ture. For low intensity rains it is reasonable to use the effect of abnormal high modu- lation of light scattered by oscillating drops, which we discovered earlier in laboratory condition and under field measurements. (The effect of abnormal high modulation al- lows us to detect 2-3 mm raindrop deformations from 5 m distance). The results of reconstruction of drop size distributions from spectra of light, scattered by rains are presented and discussed.

  20. END-TO-END VERSUS END-TO-SIDE ANASTOMOSIS IN THE TREATMENT OF ESOPHAGEAL ATRESIA OR TRACHEO-ESOPHAGEAL FISTULA

    PubMed Central

    ASKARPOUR, Shahnam; OSTADIAN, Nasrollah; PEYVASTEH, Mehran; ALAVI, Mostafa; JAVAHERIZADEH, Hazhir

    2016-01-01

    Background : Dehiscence of esophageal anastomosis is frequent and there are still controversies which type of anastomosis is preferred to diminish its incidence Aim : To compare end-to-end anastomosis versus end-to-side anastomosis in terms of anastomotic leakage, esophageal stricture and gastroesophageal reflux symptom. Methods : This study was carried out for two year starting from 2012. End-to-side and end-to-side anastomosis were compared in terms of anastomotic leakage, esophageal stricture, gastroesophageal reflux symptom, length of surgery and pack cell infusion. Results : Respectively to end-to-end and end-to-side anastomosis, duration of surgery was 127.63±13.393 minutes and 130.29±10.727 minutes (p=0.353); esophageal stricture was noted in two (5.9%) and eight (21.1%) cases (p=0.09); gastroesophageal reflux disease was detected in six (15.8%) and three (8.8%) cases (p=0.485); anastomotic leakage was found in five (13.2%) and one (2.9%) cases (p=0.203); duration of neonatal intensive care unit admission was significantly shorter in end-to-end (11.05±2.438 day) compared to end-to-side anastomosis (13.88±2.306 day) (p<0.0001). Conclusion : There were no significant differences between end-to-end and end-to-side anastomosis except for length of neonatal intensive care unit admission which was significantly shorter in end-to-end anastomosis group. PMID:27120740

  1. Reconstruction of a Broadband Spectrum of Alfvenic Fluctuations

    NASA Technical Reports Server (NTRS)

    Vinas, Adolfo F.; Fuentes, Pablo S. M.; Araneda, Jaime A.; Maneva, Yana G.

    2014-01-01

    Alfvenic fluctuations in the solar wind exhibit a high degree of velocities and magnetic field correlations consistent with Alfven waves propagating away and toward the Sun. Two remarkable properties of these fluctuations are the tendencies to have either positive or negative magnetic helicity (-1 less than or equal to sigma(sub m) less than or equal to +1) associated with either left- or right- topological handedness of the fluctuations and to have a constant magnetic field magnitude. This paper provides, for the first time, a theoretical framework for reconstructing both the magnetic and velocity field fluctuations with a divergence-free magnetic field, with any specified power spectral index and normalized magnetic- and cross-helicity spectrum field fluctuations for any plasma species. The spectrum is constructed in the Fourier domain by imposing two conditions-a divergence-free magnetic field and the preservation of the sense of magnetic helicity in both spaces-as well as using Parseval's theorem for the conservation of energy between configuration and Fourier spaces. Applications to the one-dimensional spatial Alfvenic propagation are presented. The theoretical construction is in agreement with typical time series and power spectra properties observed in the solar wind. The theoretical ideas presented in this spectral reconstruction provide a foundation for more realistic simulations of plasma waves, solar wind turbulence, and the propagation of energetic particles in such fluctuating fields.

  2. Effective reconstruction of dynamics of medium response spectrum

    NASA Astrophysics Data System (ADS)

    Trofimov, Vyacheslav A.; Varentsova, Svetlana A.

    2008-10-01

    A new algorithm is suggested to visualize the dynamics of medium response spectrum in terahertz diapason by the singly measured set of partially intersected integral characteristics of the signal. The algorithm is based on SVD method and window sliding method. The analysis, we carried out, demonstrates many advantages of the new algorithm in com-parison with the Gabor-Fourier approach, which allows obtaining the dynamics of only one spectral line for one set of measurements. Among which it is necessary to mention the possibility to get the dynamics of many spectral components simultaneously for one set of measurements as well and therefore to get the complete information about the spectrum dynamics. This allows to identify specific materials with known spectral lines and to distinguish materials with similar spectra, which is of great importance for the detection and identification of different chemicals, pharmaceutical substances and explosives. To demonstrate the efficiency of a proposed algorithm, we compare spectrum dynamics of chocolate and soap, which possess the similar spectra. Our investigation shows that their dynamics widely vary in spec-tral lines. The proposed algorithm can be also applied to voice identification and to reconstruction of a laser beam profile with a great number of local maxima. Developed algorithm allows to measure the characteristic time of medium responce. It is very important for various problems of spectroscopy.

  3. Investigating end-to-end security in the fifth generation wireless capabilities and IoT extensions

    NASA Astrophysics Data System (ADS)

    Uher, J.; Harper, J.; Mennecke, R. G.; Patton, P.; Farroha, B.

    2016-05-01

    The emerging 5th generation wireless network will be architected and specified to meet the vision of allowing the billions of devices and millions of human users to share spectrum to communicate and deliver services. The expansion of wireless networks from its current role to serve these diverse communities of interest introduces new paradigms that require multi-tiered approaches. The introduction of inherently low security components, like IoT devices, necessitates that critical data be better secured to protect the networks and users. Moreover high-speed communications that are meant to enable the autonomous vehicles require ultra reliable and low latency paths. This research explores security within the proposed new architectures and the cross interconnection of the highly protected assets with low cost/low security components forming the overarching 5th generation wireless infrastructure.

  4. Modelling and simulation of the mechanical response of a Dacron graft in the pressurization test and an end-to-end anastomosis.

    PubMed

    Bustos, Claudio A; García-Herrera, Claudio M; Celentano, Diego J

    2016-08-01

    This work presents the modeling and simulation of the mechanical response of a Dacron graft in the pressurization test and its clinical application in the analysis of an end-to-end anastomosis. Both problems are studied via an anisotropic constitutive model that was calibrated by means of previously reported uniaxial tensile tests. First, the simulation of the pressurization test allows the validation of the experimental material characterization that included tests carried out for different levels of axial stretching. Then, the analysis of an end-to-end anastomosis under an idealized geometry is proposed. This case consists in evaluating the mechanical performance of the graft together with the stresses and deformations in the neighborhood of the Dacron with the artery. This research contributes important data to understand the functioning of the graft and the possibility of extending the analysis to complex numerical cases like its insertion in the aortic arch. PMID:26826765

  5. Including 10-Gigabit-capable Passive Optical Network under End-to-End Generalized Multi-Protocol Label Switching Provisioned Quality of Service

    NASA Astrophysics Data System (ADS)

    Brewka, Lukasz; Gavler, Anders; Wessing, Henrik; Dittmann, Lars

    2012-04-01

    End-to-end quality of service provisioning is still a challenging task despite many years of research and development in this area. Considering a generalized multi-protocol label switching based core/metro network and resource reservation protocol capable home gateways, it is the access part of the network where quality of service signaling is bridged. This article proposes strategies for generalized multi-protocol label switching control over next emerging passive optical network standard, i.e., the 10-gigabit-capable passive optical network. Node management and resource allocation approaches are discussed, and possible issues are raised. The analysis shows that consideration of a 10-gigabit-capable passive optical network as a generalized multi-protocol label switching controlled domain is valid and may advance end-to-end quality of service provisioning for passive optical network based customers.

  6. End-to-end small bowel anastomosis by temperature controlled CO2 laser soldering and an albumin stent: a feasibility study

    NASA Astrophysics Data System (ADS)

    Simhon, David; Kopelman, Doron; Hashmonai, Moshe; Vasserman, Irena; Dror, Michael; Vasilyev, Tamar; Halpern, Marissa; Kariv, Naam; Katzir, Abraham

    2004-07-01

    Introduction: A feasibility study of small intestinal end to end anastomosis was performed in a rabbit model using temperature controlled CO2 laser system and an albumin stent. Compared with standard suturing or clipping, this method does not introduce foreign materials to the repaired wound and therefore, may lead to better and faster wound healing of the anastomotic site. Methods: Transected rabbits small intestines were either laser soldered using 47% bovine serum albumin and intraluminal albumin stent or served as controls in which conventional continuous two-layer end to end anastomosis was performed manually. The integrity of the anastomosis was investigated at the 14th postoperative day. Results: Postoperative course in both treatments was uneventful. The sutured group presented signs of partial bowel obstruction. Macroscopically, no signs of intraluminal fluid leakage were observed in both treatments. Yet, laser soldered intestinal anastomoses demonstrated significant superiority with respect to adhesions and narrowing of the intestinal lumen. Serial histological examinations revealed better wound healing characteristics of the laser soldered anastomotic site. Conclusion: Laser soldering of intestinal end to end anastomosis provide a faster surgical procedure, compared to standard suture technique, with better wound healing results. It is expected that this technique may be adopted in the future for minimal invasive surgeries.

  7. Planning for Mars Sample Return: Results from the MEPAG Mars Sample Return End-to-End International Science Analysis Group (E2E-iSAG)

    NASA Astrophysics Data System (ADS)

    McLennan, S. M.; Sephton, M.; Mepag E2E-Isag

    2011-12-01

    The National Research Council 2011 Planetary Decadal Survey (2013-2022) placed beginning a Mars sample return campaign (MSR) as the top priority for large Flagship missions in the coming decade. Recent developments in NASA-ESA collaborations and Decadal Survey recommendations indicate MSR likely will be an international effort. A joint ESA-NASA 2018 rover (combining the previously proposed ExoMars and MAX-C missions), designed, in part, to collect and cache samples, would thus represent the first of a 3-mission MSR campaign. The End-to-End International Science Analysis Group (E2E-iSAG) was chartered by MEPAG in August 2010 to develop and prioritize MSR science objectives and investigate implications of these objectives for defining the highest priority sample types, landing site selection criteria (and identification of reference landing sites to support engineering planning), requirements for in situ characterization on Mars to support sample selection, and priorities/strategies for returned sample analyses to determine sample sizes and numbers that would meet the objectives. MEPAG approved the E2E-iSAG report in June 2011. Science objectives, summarized in priority order, are: (1) critically assess any evidence for past life or its chemical precursors, and place constraints on past habitability and potential for preservation of signs of life, (2) quantitatively constrain age, context and processes of accretion, early differentiation and magmatic and magnetic history, (3) reconstruct history of surface and near-surface processes involving water, (4) constrain magnitude, nature, timing, and origin of past climate change, (5) assess potential environmental hazards to future human exploration, (6) assess history and significance of surface modifying processes, (7) constrain origin and evolution of the Martian atmosphere, (8) evaluate potential critical resources for future human explorers. All returned samples also would be fully evaluated for extant life as a

  8. An end-to-end system in support of a broad scope of GOES-R sensor and data processing study

    NASA Astrophysics Data System (ADS)

    Huang, Hung-Lung

    2005-08-01

    The mission of NOAA's Geostationary Operational Environmental Satellite System (GOES) R series satellites, in the 2012 time frame, is to provide continuous, near real-time meteorological, oceanographic, solar, and space environment data that supports NOAA's strategic mission goals. It presents an exciting opportunity to explore new instruments, satellite designs, and system architectures utilizing new communication and instrument technologies in order to meet the ever-increasing demands made of Earth observation systems by national agencies and end users alike. The GOES-R sensor suite includes a 16 spectral band Advanced Baseline Imager (ABI), an approximately 1500 high spectral resolution band Hyperspectral Environmental Suite (HES), plus other sensors designed to detect lightning and to explore the ocean, solar and space environment. The Cooperative Institute for Meteorological Satellite Studies (CIMSS) as part of the Space Science and Engineering Center (SSEC) of the University of Wisconsin-Madison, the long time partner of NOAA, has developed the first operational end-to-end processing system for GOES. Based on this heritage, and with recent support from the NASA/NOAA Geosynchrous Imaging FTS (GIFTS) project, the Navy's Multiple University Research Initiative (MURI), and NOAA's GOES-R Risk Reduction program, SSEC has built a near-complete end-to-end system that is capable of simulating sensor measurements from top of atmosphere radiances, raw sensor data (level 0) through calibrated and navigated sensor physical measurements (level 1) to the processed products (level 2). In this paper, the SSEC Hyperspectral Imaging and Sounding Simulator and Processor (HISSP) will be presented in detail. HISSP is capable of demonstrating most of the processing functions such as data compression/decompression, sensor calibration, data processing, algorithm development, and product generation. In summary, HISSP is an end-to-end system designed to support both government and

  9. On-Orbit Performance Verification and End-To-End Characterization of the TDRS-H Ka-band Communications Payload

    NASA Technical Reports Server (NTRS)

    Toral, Marco; Wesdock, John; Kassa, Abby; Pogorelc, Patsy; Jenkens, Robert (Technical Monitor)

    2002-01-01

    In June 2000, NASA launched the first of three next generation Tracking and Data Relay Satellites (TDRS-H) equipped with a Ka-band forward and return service capability. This Ka-band service supports forward data rates of up to 25 Mb/sec using the 22.55-23.55 GHz space-to-space allocation. Return services are supported via channel bandwidths of 225 and 650 MHz for data rates up to at least 800 Mb/sec using the 25.25 - 27.5 GHz space-to-space allocation. As part of NASA's acceptance of the TDRS-H spacecraft, an extensive on-orbit calibration, verification and characterization effort was performed to ensure that on-orbit spacecraft performance is within specified limits. This process verified the compliance of the Ka-band communications payload with all performance specifications, and demonstrated an end-to-end Ka-band service capability. This paper summarizes the results of the TDRS-H Ka-band communications payload on-orbit performance verification and end-to-end service characterization. Performance parameters addressed include antenna gain pattern, antenna Gain-to-System Noise Temperature (G/T), Effective Isotropically Radiated Power (EIRP), antenna pointing accuracy, frequency tunability, channel magnitude response, and Ka-band service Bit-Error-Rate (BER) performance.

  10. On-Orbit Performance Verification and End-to-End Characterization of the TDRS-H Ka-Band Communications Payload

    NASA Technical Reports Server (NTRS)

    Toral, Marco; Wesdock, John; Kassa, Abby; Pogorelc, Patsy; Jenkens, Robert (Technical Monitor)

    2002-01-01

    In June 2000, NASA launched the first of three next generation Tracking and Data Relay Satellites (TDRS-H) equipped with a Ka-band forward and return service capability. This Ka-band service supports forward data rates up to 25 Mb/sec using the 22.55 - 23.55 GHz space-to-space allocation. Return services are supported via channel bandwidths of 225 and 650 MHz for data rates up to 800 Mb/sec (QPSK) using the 25.25 - 27.5 GHz space-to-space allocation. As part of NASA's acceptance of the TDRS-H spacecraft, an extensive on-orbit calibration, verification and characterization effort was performed to ensure that on-orbit spacecraft performance is within specified limits. This process verified the compliance of the Ka-band communications payload with all performance specifications and demonstrated an end-to-end Ka-band service capability. This paper summarizes the results of the TDRS-H Ka-band communications payload on-orbit performance verification and end-to-end service characterization. Performance parameters addressed include Effective Isotropically Radiated Power (EIRP), antenna Gain-to-System Noise Temperature (G/T), antenna gain pattern, frequency tunability and accuracy, channel magnitude response, and Ka-band service Bit-Error-Rate (BER) performance.

  11. User-oriented end-to-end transport protocols for the real-time distribution of telemetry data from NASA spacecraft

    NASA Technical Reports Server (NTRS)

    Hooke, A. J.

    1979-01-01

    A set of standard telemetry protocols for downlink data flow facilitating the end-to-end transport of instrument data from the spacecraft to the user in real time is proposed. The direct switching of data by autonomous message 'packets' that are assembled by the source instrument on the spacecraft is discussed. The data system consists thus of a format on a message rather than word basis, and such packet telemetry would include standardized protocol headers. Standards are being developed within the NASA End-to-End Data System (NEEDS) program for the source packet and transport frame protocols. The source packet protocol contains identification of both the sequence number of the packet as it is generated by the source and the total length of the packet, while the transport frame protocol includes a sequence count defining the serial number of the frame as it is generated by the spacecraft data system, and a field specifying any 'options' selected in the format of the frame itself.

  12. Mixed integer nonlinear programming model of wireless pricing scheme with QoS attribute of bandwidth and end-to-end delay

    NASA Astrophysics Data System (ADS)

    Irmeilyana, Puspita, Fitri Maya; Indrawati

    2016-02-01

    The pricing for wireless networks is developed by considering linearity factors, elasticity price and price factors. Mixed Integer Nonlinear Programming of wireless pricing model is proposed as the nonlinear programming problem that can be solved optimally using LINGO 13.0. The solutions are expected to give some information about the connections between the acceptance factor and the price. Previous model worked on the model that focuses on bandwidth as the QoS attribute. The models attempt to maximize the total price for a connection based on QoS parameter. The QoS attributes used will be the bandwidth and the end to end delay that affect the traffic. The maximum goal to maximum price is achieved when the provider determine the requirement for the increment or decrement of price change due to QoS change and amount of QoS value.

  13. Demonstration of a fully-coupled end-to-end model for small pelagic fish using sardine and anchovy in the California Current

    NASA Astrophysics Data System (ADS)

    Rose, Kenneth A.; Fiechter, Jerome; Curchitser, Enrique N.; Hedstrom, Kate; Bernal, Miguel; Creekmore, Sean; Haynie, Alan; Ito, Shin-ichi; Lluch-Cota, Salvador; Megrey, Bernard A.; Edwards, Chris A.; Checkley, Dave; Koslow, Tony; McClatchie, Sam; Werner, Francisco; MacCall, Alec; Agostini, Vera

    2015-11-01

    We describe and document an end-to-end model of anchovy and sardine population dynamics in the California Current as a proof of principle that such coupled models can be developed and implemented. The end-to-end model is 3-dimensional, time-varying, and multispecies, and consists of four coupled submodels: hydrodynamics, Eulerian nutrient-phytoplankton-zooplankton (NPZ), an individual-based full life cycle anchovy and sardine submodel, and an agent-based fishing fleet submodel. A predator roughly mimicking albacore was included as individuals that consumed anchovy and sardine. All submodels were coded within the ROMS open-source community model, and used the same resolution spatial grid and were all solved simultaneously to allow for possible feedbacks among the submodels. We used a super-individual approach and solved the coupled models on a distributed memory parallel computer, both of which created challenging but resolvable bookkeeping challenges. The anchovy and sardine growth, mortality, reproduction, and movement, and the fishing fleet submodel, were each calibrated using simplified grids before being inserted into the full end-to-end model. An historical simulation of 1959-2008 was performed, and the latter 45 years analyzed. Sea surface height (SSH) and sea surface temperature (SST) for the historical simulation showed strong horizontal gradients and multi-year scale temporal oscillations related to various climate indices (PDO, NPGO), and both showed responses to ENSO variability. Simulated total phytoplankton was lower during strong El Nino events and higher for the strong 1999 La Nina event. The three zooplankton groups generally corresponded to the spatial and temporal variation in simulated total phytoplankton. Simulated biomasses of anchovy and sardine were within the historical range of observed biomasses but predicted biomasses showed much less inter-annual variation. Anomalies of annual biomasses of anchovy and sardine showed a switch in the mid

  14. End to end assembly of CaO and ZnO nanosheets to propeller-shaped architectures by orientation attachment approaches

    NASA Astrophysics Data System (ADS)

    Zhang, Yong; Liu, Fang

    2015-06-01

    Inspired by the agitation effect of propellers, heterogeneous propeller- shaped CaO/ZnO architectures were assembled in aqueous solution. Preferred nucleation and growth of CaO and ZnO nuclei resulted in their hexagonal nanosheets, and they were end to end combined into propeller-shaped architectures by oriented rotation and attachment reactions. When propeller-shaped CaO/ZnO product was used as solid base catalyst to synthesize biodiesel, a high biodiesel yield of 97.5% was achieved. The predominant exposure of active O2- on CaO(0 0 2) and ZnO(0 0 0 2) planes in propeller-shaped CaO/ZnO, led to good catalytic activity and high yield of biodiesel.

  15. Clinical evaluation of a closed, one-stage, stapled, functional, end-to-end jejuno-ileal anastomosis in 5 horses

    PubMed Central

    Anderson, Stacy L.; Blackford, James T.; Kelmer, S. Gal

    2012-01-01

    This study describes the outcome and complications in horses that had a closed, one-stage, stapled, functional, end-to-end (COSFE) jejuno-ileal anastomosis (JIA) following resection of compromised small intestine. Medical records were reviewed to identify all horses that had a COSFE JIA performed during exploratory laparotomy and to determine post-operative complications and final outcome. All 5 horses that were identified had successful COSFE JIA with resection of various amounts of distal jejunum and proximal ileum. Post-operative ileus occurred in 1 of the 5 horses. All horses survived at least 1 year after surgery. The survival times and incidence of post-operative ileus compared favorably with published results for other types of small intestinal resection and anastomoses. A COSFE JIA is a viable surgical procedure to correct lesions of the distal jejunum and proximal ileum. PMID:23450864

  16. End-to-End Study of the Transfer of Energy from Magnetosheath Ion Precipitation to the Ionospheric Cusp and Resulting Ion Outflow to the Magnetosphere

    NASA Technical Reports Server (NTRS)

    Coffey, Victoria; Chandler, Michael; Singh, Nagendra; Avanov, Levon

    2003-01-01

    We will show results from an end-to-end study of the energy transfer from injected magnetosheath plasmas to the near-Earth magnetospheric and ionospheric plasmas and the resulting ion outflow to the magnetosphere. This study includes modeling of the evolution of the magnetosheath precipitation in the cusp using a kinetic code with a realistic magnetic field configuration. These evolved, highly non-Maxwellian distributions are used as input to a 2D PIC code to analyze the resulting wave generation. The wave analysis is used in the kinetic code as input to the cold ionospheric ions to study the transfer of energy to these ions and their outflow to the magnetosphere. Observations from the Thermal Ion Dynamics Experiment (TIDE) and other instruments on the Polar Spacecraft will be compared to the modeling.

  17. An end-to-end approach to the EUCLID NISP on-board pre-processing operations: tests and latest results

    NASA Astrophysics Data System (ADS)

    Bonoli, Carlotta; Bortoletto, Favio; D'Alessandro, Maurizio; Corcione, Leonardo; Ligori, Sebastiano; Nicastro, Luciano; Trifoglio, Massimo; Valenziano, Luca; Zerbi, Filippo M.; Crouzet, Pierre-Elie; Jung, Andreas

    2012-09-01

    NISP is the near IR spectrophotometer instrument part of the Cosmic Vision Euclid mission. In this paper we describe an end-to-end simulation scheme developed in the framework of the NISP design study to cover the expected focal-plane on-board pre-processing operations. Non-destructive detector readouts are simulated for a number of different readout strategies, taking into account scientific and calibration observations; resulting frames are passed through a series of steps emulating the foreseen on-board pipeline, then compressed to give the final result. In order to verify final frame quality and resulting computational and memory load, we tested this architecture on a number of hardware platforms similar to those possible for the final NISP computing unit. Here we give the results of the latest tests. This paper mainly reports the technical status at the end of the Definition Phase and it is presented on behalf of the Euclid Consortium.

  18. Application of modified direct denitration to support the ORNL coupled-end-to-end demonstration in production of mixed oxides suitable for pellet fabrication

    SciTech Connect

    Walker, E.A.; Vedder, R.J.; Felker, L.K.; Marschman, S.C.

    2007-07-01

    The current and future development of the Modified Direct Denitration (MDD) process is in support of Oak Ridge National Laboratory's (ORNL) Coupled End-to-End (CETE) research, development, and demonstration (R and D) of proposed advanced fuel reprocessing and fuel fabrication processes. This work will involve the co-conversion of the U/Pu/Np product streams from the UREX+3 separation flow sheet utilizing the existing MDD glove-box setup and the in-cell co-conversion of the U/Pu/Np/Am/Cm product streams from the UREX+1a flow sheet. Characterization equipment is being procured and installed. Oxide powder studies are being done on calcination/reduction variables, as well as pressing and sintering of pellets to permit metallographic examinations. (authors)

  19. The application of MUSIC algorithm in spectrum reconstruction and interferogram processing

    NASA Astrophysics Data System (ADS)

    Jian, Xiaohua; Zhang, Chunmin; Zhao, Baochang; Zhu, Baohui

    2008-05-01

    Three different methods of spectrum reproduction and interferogram processing are discussed and contrasted in this paper. Especially, the nonparametric model of MUSIC (multiple signal classification) algorithm is firstly brought into the practical spectrum reconstruction processing. The experimental results prove that this method has immensely improved the resolution of reproduced spectrum, and provided a better math model for super advanced resolving power in spectrum reconstruction. The usefulness and simplicity of the technique will lead the interference imaging spectrometers to almost every field into which the spectroscopy has ventured and into some where it has not gone before.

  20. The role of environmental controls in determining sardine and anchovy population cycles in the California Current: Analysis of an end-to-end model

    NASA Astrophysics Data System (ADS)

    Fiechter, Jerome; Rose, Kenneth A.; Curchitser, Enrique N.; Hedstrom, Katherine S.

    2015-11-01

    Sardine and anchovy are two forage species of particular interest because of their low-frequency cycles in adult abundance in boundary current regions, combined with a commercially relevant contribution to the global marine food catch. While several hypotheses have been put forth to explain decadal shifts in sardine and anchovy populations, a mechanistic basis for how the physics, biogeochemistry, and biology combine to produce patterns of synchronous variability across widely separated systems has remained elusive. The present study uses a 50-year (1959-2008) simulation of a fully coupled end-to-end ecosystem model configured for sardine and anchovy in the California Current System to investigate how environmental processes control their population dynamics. The results illustrate that slightly different temperature and diet preferences can lead to significantly different responses to environmental variability. Simulated adult population fluctuations are associated with age-1 growth (via age-2 egg production) and prey availability for anchovy, while they depend primarily on age-0 survival and temperature for sardine. The analysis also hints at potential linkages to known modes of climate variability, whereby changes in adult abundance are related to ENSO for anchovy and to the PDO for sardine. The connection to the PDO and ENSO is consistent with modes of interannual and decadal variability that would alternatively favor anchovy during years of cooler temperatures and higher prey availability, and sardine during years of warmer temperatures and lower prey availability. While the end-to-end ecosystem model provides valuable insight on potential relationships between environmental conditions and sardine and anchovy population dynamics, understanding the complex interplay, and potential lags, between the full array of processes controlling their abundances in the California Current System remains an on-going challenge.

  1. Imaging and dosimetric errors in 4D PET/CT-guided radiotherapy from patient-specific respiratory patterns: a dynamic motion phantom end-to-end study

    NASA Astrophysics Data System (ADS)

    Bowen, S. R.; Nyflot, M. J.; Herrmann, C.; Groh, C. M.; Meyer, J.; Wollenweber, S. D.; Stearns, C. W.; Kinahan, P. E.; Sandison, G. A.

    2015-05-01

    Effective positron emission tomography / computed tomography (PET/CT) guidance in radiotherapy of lung cancer requires estimation and mitigation of errors due to respiratory motion. An end-to-end workflow was developed to measure patient-specific motion-induced uncertainties in imaging, treatment planning, and radiation delivery with respiratory motion phantoms and dosimeters. A custom torso phantom with inserts mimicking normal lung tissue and lung lesion was filled with [18F]FDG. The lung lesion insert was driven by six different patient-specific respiratory patterns or kept stationary. PET/CT images were acquired under motionless ground truth, tidal breathing motion-averaged (3D), and respiratory phase-correlated (4D) conditions. Target volumes were estimated by standardized uptake value (SUV) thresholds that accurately defined the ground-truth lesion volume. Non-uniform dose-painting plans using volumetrically modulated arc therapy were optimized for fixed normal lung and spinal cord objectives and variable PET-based target objectives. Resulting plans were delivered to a cylindrical diode array at rest, in motion on a platform driven by the same respiratory patterns (3D), or motion-compensated by a robotic couch with an infrared camera tracking system (4D). Errors were estimated relative to the static ground truth condition for mean target-to-background (T/Bmean) ratios, target volumes, planned equivalent uniform target doses, and 2%-2 mm gamma delivery passing rates. Relative to motionless ground truth conditions, PET/CT imaging errors were on the order of 10-20%, treatment planning errors were 5-10%, and treatment delivery errors were 5-30% without motion compensation. Errors from residual motion following compensation methods were reduced to 5-10% in PET/CT imaging, <5% in treatment planning, and <2% in treatment delivery. We have demonstrated that estimation of respiratory motion uncertainty and its propagation from PET/CT imaging to RT planning, and RT

  2. Imaging and dosimetric errors in 4D PET/CT-guided radiotherapy from patient-specific respiratory patterns: a dynamic motion phantom end-to-end study

    PubMed Central

    Bowen, S R; Nyflot, M J; Hermann, C; Groh, C; Meyer, J; Wollenweber, S D; Stearns, C W; Kinahan, P E; Sandison, G A

    2015-01-01

    Effective positron emission tomography/computed tomography (PET/CT) guidance in radiotherapy of lung cancer requires estimation and mitigation of errors due to respiratory motion. An end-to-end workflow was developed to measure patient-specific motion-induced uncertainties in imaging, treatment planning, and radiation delivery with respiratory motion phantoms and dosimeters. A custom torso phantom with inserts mimicking normal lung tissue and lung lesion was filled with [18F]FDG. The lung lesion insert was driven by 6 different patient-specific respiratory patterns or kept stationary. PET/CT images were acquired under motionless ground truth, tidal breathing motion-averaged (3D), and respiratory phase-correlated (4D) conditions. Target volumes were estimated by standardized uptake value (SUV) thresholds that accurately defined the ground-truth lesion volume. Non-uniform dose-painting plans using volumetrically modulated arc therapy (VMAT) were optimized for fixed normal lung and spinal cord objectives and variable PET-based target objectives. Resulting plans were delivered to a cylindrical diode array at rest, in motion on a platform driven by the same respiratory patterns (3D), or motion-compensated by a robotic couch with an infrared camera tracking system (4D). Errors were estimated relative to the static ground truth condition for mean target-to-background (T/Bmean) ratios, target volumes, planned equivalent uniform target doses (EUD), and 2%-2mm gamma delivery passing rates. Relative to motionless ground truth conditions, PET/CT imaging errors were on the order of 10–20%, treatment planning errors were 5–10%, and treatment delivery errors were 5–30% without motion compensation. Errors from residual motion following compensation methods were reduced to 5–10% in PET/CT imaging, < 5% in treatment planning, and < 2% in treatment delivery. We have demonstrated that estimation of respiratory motion uncertainty and its propagation from PET/CT imaging to RT

  3. Wide-spectrum reconstruction method for a birefringence interference imaging spectrometer.

    PubMed

    Zhang, Chunmin; Jian, Xiaohua

    2010-02-01

    We present a mathematical method used to determine the spectrum detected by a birefringence interference imaging spectrometer (BIIS). The reconstructed spectrum has good precision over a wide spectral range, 0.4-1.0 microm. This method considers the light intensity as a function of wavelength and avoids the fatal error caused by birefringence effect in the conventional Fourier transform method. The experimental interferogram of the BIIS is processed in this new way, and the interference data and reconstructed spectrum are in good agreement, proving this method to be very exact and useful. Application of this method will greatly improve the instrument performance. PMID:20125723

  4. Precise spectrum reconstruction of the Fourier transforms imaging spectrometer based on polarization beam splitters.

    PubMed

    Ren, Wenyi; Zhang, Chunmin; Jia, Chenling; Mu, Tingkui; Li, Qiwei; Zhang, Lin

    2013-04-15

    A method was proposed to precisely reconstruct the spectrum from the interferogram taken by the Fourier transform imaging spectrometer (FTIS) based on the polarization beam splitters. Taken the FTISs based on the Savart polariscope and Wollaston prism as examples, the distorted spectrums were corrected via the proposed method effectively. The feasibility of the method was verified via simulation. The distorted spectrum, recovered from the interferogram taken by the polarization imaging spectrometer developed by us, was corrected. PMID:23595463

  5. Overview of Non-nuclear Testing of the Safe, Affordable 30-kW Fission Engine, Including End-to-End Demonstrator Testing

    NASA Technical Reports Server (NTRS)

    VanDyke, M. K.; Martin, J. J.; Houts, M. G.

    2003-01-01

    Successful development of space fission systems will require an extensive program of affordable and realistic testing. In addition to tests related to design/development of the fission system, realistic testing of the actual flight unit must also be performed. At the power levels under consideration (3-300 kW electric power), almost all technical issues are thermal or stress related and will not be strongly affected by the radiation environment. These issues can be resolved more thoroughly, less expensively, and in a more timely fashing with nonnuclear testing, provided it is prototypic of the system in question. This approach was used for the safe, affordable fission engine test article development program and accomplished viz cooperative efforts with Department of Energy labs, industry, universiites, and other NASA centers. This Technical Memorandum covers the analysis, testing, and data reduction of a 30-kW simulated reactor as well as an end-to-end demonstrator, including a power conversion system and an electric propulsion engine, the first of its kind in the United States.

  6. Ecosystem limits to food web fluxes and fisheries yields in the North Sea simulated with an end-to-end food web model

    NASA Astrophysics Data System (ADS)

    Heath, Michael R.

    2012-09-01

    Equilibrium yields from an exploited fish stock represent the surplus production remaining after accounting for losses due to predation. However, most estimates of maximum sustainable yield, upon which fisheries management targets are partly based, assume that productivity and predation rates are constant in time or at least stationary. This means that there is no recognition of the potential for interaction between different fishing sectors. Here, an end-to-end ecosystem model is developed to explore the possible scale and mechanisms of interactions between pelagic and demersal fishing in the North Sea. The model simulates fluxes of nitrogen between detritus, inorganic nutrient and guilds of taxa spanning phytoplankton to mammals. The structure strikes a balance between graininess in space, taxonomy and demography, and the need to constrain the parameter-count sufficiently to enable automatic parameter optimization. Simulated annealing is used to locate the maximum likelihood parameter set, given the model structure and a suite of observations of annual rates of production and fluxes between guilds. Simulations of the impact of fishery harvesting rates showed that equilibrium yields of pelagic and demersal fish were strongly interrelated due to a variety of top-down and bottom-up food web interactions. The results clearly show that management goals based on simultaneously achieving maximum sustainable biomass yields from all commercial fish stocks is simply unattainable. Trade-offs between, for example, pelagic and demersal fishery sectors and other properties of the ecosystem have to be considered in devising an overall harvesting strategy.

  7. AFCI Coupled End-to-End Research,Development and Demonstration Project: Integrated Off-gas Treatment System Design and Initial Performance - 9226

    SciTech Connect

    Jubin, Robert Thomas; Patton, Bradley D; Ramey, Dan W; Spencer, Barry B

    2009-01-01

    Oak Ridge National Laboratory is conducting a complete, coupled end-to-end (CETE) demonstration of advanced nuclear fuel reprocessing to support the Advanced Fuel Cycle Initiative. This small-scale reprocessing operation provides a unique opportunity to test integrated off-gas treatment systems designed to recover the primary volatile fission and activation products (H-3, C-14, Kr-85, and I-139) released from the spent nuclear fuel (SNF). The CETE project will demonstrate an advanced head-end process, referred to as voloxidation, designed to condition the SNF, separate the SNF from the cladding, and release tritium contained in the fuel matrix. The off-gas from the dry voloxidation process as well as from the more traditional fuel dissolution process will be treated separately and the volatile components recovered. This paper provides descriptions of the off-gas treatment systems for both the voloxidation process and for the fuel dissolution process and provides preliminary results from the initial CETE processing runs. Impacts of processing parameters on the relative quantities of volatile components released and recovery efficiencies are evaluated.

  8. Land Mobile Satellite Service (LMSS) channel simulator: An end-to-end hardware simulation and study of the LMSS communications links

    NASA Technical Reports Server (NTRS)

    Salmasi, A. B. (Editor); Springett, J. C.; Sumida, J. T.; Richter, P. H.

    1984-01-01

    The design and implementation of the Land Mobile Satellite Service (LMSS) channel simulator as a facility for an end to end hardware simulation of the LMSS communications links, primarily with the mobile terminal is described. A number of studies are reported which show the applications of the channel simulator as a facility for validation and assessment of the LMSS design requirements and capabilities by performing quantitative measurements and qualitative audio evaluations for various link design parameters and channel impairments under simulated LMSS operating conditions. As a first application, the LMSS channel simulator was used in the evaluation of a system based on the voice processing and modulation (e.g., NBFM with 30 kHz of channel spacing and a 2 kHz rms frequency deviation for average talkers) selected for the Bell System's Advanced Mobile Phone Service (AMPS). The various details of the hardware design, qualitative audio evaluation techniques, signal to channel impairment measurement techniques, the justifications for criteria of different parameter selection in regards to the voice processing and modulation methods, and the results of a number of parametric studies are further described.

  9. Distributed Large Data-Object Environments: End-to-End Performance Analysis of High Speed Distributed Storage Systems in Wide Area ATM Networks

    NASA Technical Reports Server (NTRS)

    Johnston, William; Tierney, Brian; Lee, Jason; Hoo, Gary; Thompson, Mary

    1996-01-01

    We have developed and deployed a distributed-parallel storage system (DPSS) in several high speed asynchronous transfer mode (ATM) wide area networks (WAN) testbeds to support several different types of data-intensive applications. Architecturally, the DPSS is a network striped disk array, but is fairly unique in that its implementation allows applications complete freedom to determine optimal data layout, replication and/or coding redundancy strategy, security policy, and dynamic reconfiguration. In conjunction with the DPSS, we have developed a 'top-to-bottom, end-to-end' performance monitoring and analysis methodology that has allowed us to characterize all aspects of the DPSS operating in high speed ATM networks. In particular, we have run a variety of performance monitoring experiments involving the DPSS in the MAGIC testbed, which is a large scale, high speed, ATM network and we describe our experience using the monitoring methodology to identify and correct problems that limit the performance of high speed distributed applications. Finally, the DPSS is part of an overall architecture for using high speed, WAN's for enabling the routine, location independent use of large data-objects. Since this is part of the motivation for a distributed storage system, we describe this architecture.

  10. Reconstructing phylogeny from the multifractal spectrum of mitochondrial DNA

    NASA Astrophysics Data System (ADS)

    Glazier, James A.; Raghavachari, Sridhar; Berthelsen, Cheryl L.; Skolnick, Mark H.

    1995-03-01

    Conventional methods of phylogenetic reconstruction from DNA sequences require simplified models of evolutionary dynamics. We present a method based on fractal analysis to reconstruct the evolutionary history of organisms from mitochondrial DNA sequences. We map animal mtDNA into four-dimensional random walks and estimate their long range correlations using multifractal spectra. We see systematic changes in correlations in mtDNA sequences across taxonomic lines, which translate into changes in the scaling of the random walks. We use cluster analysis to group the multifractal spectra and obtain the phylogeny of the organisms. Though our method uses no a priori assumptions and is independent of gene order, it yields phylogenetic relationships broadly consistent with established results. Several recent papers have analyzed DNA using fractal analysis and have found long range correlations. However, no one has succeeded in using them to deduce biologically significant relationships.

  11. Reconstruction of off-axis lensless Fourier transform digital holograms based on angular spectrum theory

    NASA Astrophysics Data System (ADS)

    Wang, Guangjun; Wang, Huaying; Wang, Dayong; Xie, Jianjun; Zhao, Jie

    2007-12-01

    A simple holographic high-resolution imaging system without pre-magnification, which is based on off-axis lensless Fourier transform configuration, has been developed. Experimental investigations are performed on USAF resolution test target. The method based on angular spectrum theory for reconstructing lensless Fourier hologram is given. The reconstructed results of the same hologram at different reconstructing distances are presented for what is to our knowledge the first time. Approximate diffraction limited lateral resolution is achieved. The results show that the angular spectrum method has several advantages over more commonly used Fresnel transform method. Lossless reconstruction can be achieved for any numerical aperture holograms as long as the wave field is calculated at a special reconstructing distance, which is determined by the light wavelength and the chip size and the pixel size of the CCD sensor. This is very important for reconstructing an extremely large numerical aperture hologram. Frequency-domain spectrum filtering can be applied conveniently to remove the disturbance of zero-order. The reconstructed image wave field is accurate so long as the sampling theorem is not violated. The experimental results also demonstrate that for a high quality hologram, special image processing is unnecessary to obtain a high quality image.

  12. Design of a satellite end-to-end mission performance simulator for imaging spectrometers and its application to the ESA's FLEX/Sentinel-3 tandem mission

    NASA Astrophysics Data System (ADS)

    Vicent, Jorge; Sabater, Neus; Tenjo, Carolina; Acarreta, Juan R.; Manzano, María.; Rivera, Juan P.; Jurado, Pedro; Franco, Raffaella; Alonso, Luis; Moreno, Jose

    2015-09-01

    The performance analysis of a satellite mission requires specific tools that can simulate the behavior of the platform; its payload; and the acquisition of scientific data from synthetic scenes. These software tools, called End-to-End Mission Performance Simulators (E2ES), are promoted by the European Space Agency (ESA) with the goal of consolidating the instrument and mission requirements as well as optimizing the implemented data processing algorithms. Nevertheless, most developed E2ES are designed for a specific satellite mission and can hardly be adapted to other satellite missions. In the frame of ESA's FLEX mission activities, an E2ES is being developed based on a generic architecture for passive optical missions. FLEX E2ES implements a state-of-the-art synthetic scene generator that is coupled with dedicated algorithms that model the platform and instrument characteristics. This work will describe the flexibility of the FLEX E2ES to simulate complex synthetic scenes with a variety of land cover classes, topography and cloud cover that are observed separately by each instrument (FLORIS, OLCI and SLSTR). The implemented algorithms allows modelling the sensor behavior, i.e. the spectral/spatial resampling of the input scene; the geometry of acquisition; the sensor noises and non-uniformity effects (e.g. stray-light, spectral smile and radiometric noise); and the full retrieval scheme up to Level-2 products. It is expected that the design methodology implemented in FLEX E2ES can be used as baseline for other imaging spectrometer missions and will be further expanded towards a generic E2ES software tool.

  13. Assessing the value of seasonal climate forecast information through an end-to-end forecasting framework: Application to U.S. 2012 drought in central Illinois

    NASA Astrophysics Data System (ADS)

    Shafiee-Jood, Majid; Cai, Ximing; Chen, Ligang; Liang, Xin-Zhong; Kumar, Praveen

    2014-08-01

    This study proposes an end-to-end forecasting framework to incorporate operational seasonal climate forecasts to help farmers improve their decisions prior to the crop growth season, which are vulnerable to unanticipated drought conditions. The framework couples a crop growth model with a decision-making model for rainfed agriculture and translates probabilistic seasonal forecasts into more user-related information that can be used to support farmers' decisions on crop type and some market choices (e.g., contracts with ethanol refinery). The regional Climate-Weather Research and Forecasting model (CWRF) driven by two operational general circulation models (GCMs) is used to provide the seasonal forecasts of weather parameters. To better assess the developed framework, CWRF is also driven by observational reanalysis data, which theoretically can be considered as the best seasonal forecast. The proposed framework is applied to the Salt Creek watershed in Illinois that experienced an extreme drought event during 2012 crop growth season. The results show that the forecasts cannot capture the 2012 drought condition in Salt Creek and therefore the suggested decisions can make farmers worse off if the suggestions are adopted. Alternatively, the optimal decisions based on reanalysis-based CWRF forecasts, which can capture the 2012 drought conditions, make farmers better off by suggesting "no-contract" with ethanol refineries. This study suggests that the conventional metric used for ex ante value assessment is not capable of providing meaningful information in the case of extreme drought. Also, it is observed that institutional interventions (e.g., crop insurance) highly influences farmers' decisions and, thereby, the assessment of forecast value.

  14. The Hurricane-Flood-Landslide Continuum: An Integrated, End-to-end Forecast and Warning System for Mountainous Islands in the Tropics

    NASA Astrophysics Data System (ADS)

    Golden, J.; Updike, R. G.; Verdin, J. P.; Larsen, M. C.; Negri, A. J.; McGinley, J. A.

    2004-12-01

    In the 10 days of 21-30 September 1998, Hurricane Georges left a trail of destruction in the Caribbean region and U.S. Gulf Coast. Subsequently, in the same year, Hurricane Mitch caused widespread destruction and loss of life in four Central American nations, and in December,1999 a tropical disturbance impacted the north coast of Venezuela causing hundreds of deaths and several million dollars of property loss. More recently, an off-season disturbance in the Central Caribbean dumped nearly 250 mm rainfall over Hispaniola during the 24-hr period on May 23, 2004. Resultant flash floods and debris flows in the Dominican Republic and Haiti killed at least 1400 people. In each instance, the tropical system served as the catalyst for major flooding and landslides at landfall. Our goal is to develop and transfer an end-to-end warning system for a prototype region in the Central Caribbean, specifically the islands of Puerto Rico and Hispaniola, which experience frequent tropical cyclones and other disturbances. The envisioned system would include satellite and surface-based observations to track and nowcast dangerous levels of precipitation, atmospheric and hydrological models to predict short-term runoff and streamflow changes, geological models to warn when and where landslides and debris flows are imminent, and the capability to communicate forecast guidance products via satellite to vital government offices in Puerto Rico, Haiti, and the Dominican Republic. In this paper, we shall present a preliminary proof-of-concept study for the May 21-24, 2004 floods and debris-flows over Hispaniola to show that the envisaged flow of data, models and graphical products can produce the desired warning outputs. The multidisciplinary research and technology transfer effort will require blending the talents of hydrometeorologists, geologists, remote sensing and GIS experts, and social scientists to ensure timely delivery of tailored graphical products to both weather offices and local

  15. Reconstruction of the primordial power spectrum using temperature and polarisation data from multiple experiments

    SciTech Connect

    Nicholson, Gavin; Contaldi, Carlo R. E-mail: c.contaldi@imperial.ac.uk

    2009-07-01

    We develop a method to reconstruct the primordial power spectrum, P(k), using both temperature and polarisation data from the joint analysis of a number of Cosmic Microwave Background (CMB) observations. The method is an extension of the Richardson-Lucy algorithm, first applied in this context by Shafieloo and Souradeep [1]. We show how the inclusion of polarisation measurements can decrease the uncertainty in the reconstructed power spectrum. In particular, the polarisation data can constrain oscillations in the spectrum more effectively than total intensity only measurements. We apply the estimator to a compilation of current CMB results. The reconstructed spectrum is consistent with the best-fit power spectrum although we find evidence for a 'dip' in the power on scales k ≈ 0.002 Mpc{sup −1}. This feature appears to be associated with the WMAP power in the region 18 ≤ l ≤ 26 which is consistently below best-fit models. We also forecast the reconstruction for a simulated, Planck-like [2] survey including sample variance limited polarisation data.

  16. Reconstruction of the primordial power spectrum using temperature and polarisation data from multiple experiments

    NASA Astrophysics Data System (ADS)

    Nicholson, Gavin; Contaldi, Carlo R.

    2009-07-01

    We develop a method to reconstruct the primordial power spectrum, P(k), using both temperature and polarisation data from the joint analysis of a number of Cosmic Microwave Background (CMB) observations. The method is an extension of the Richardson-Lucy algorithm, first applied in this context by Shafieloo & Souradeep [1]. We show how the inclusion of polarisation measurements can decrease the uncertainty in the reconstructed power spectrum. In particular, the polarisation data can constrain oscillations in the spectrum more effectively than total intensity only measurements. We apply the estimator to a compilation of current CMB results. The reconstructed spectrum is consistent with the best-fit power spectrum although we find evidence for a `dip' in the power on scales k approx 0.002 Mpc-1. This feature appears to be associated with the WMAP power in the region 18 <= ell <= 26 which is consistently below best-fit models. We also forecast the reconstruction for a simulated, Planck-like [2] survey including sample variance limited polarisation data.

  17. A practical statistical polychromatic image reconstruction for computed tomography using spectrum binning

    NASA Astrophysics Data System (ADS)

    Wu, Meng; Yang, Qiao; Maier, Andreas; Fahrig, Rebecca

    2014-03-01

    Polychromatic statistical reconstruction algorithms have very high computational demands due to the difficulty of the optimization problems and the large number of spectrum bins. We want to develop a more practical algorithm that has a simpler optimization problem, a faster numerical solver, and requires only a small amount of prior knowledge. In this paper, a modified optimization problem for polychromatic statistical reconstruction algorithms is proposed. The modified optimization problem utilizes the idea of determining scanned materials based on a first pass FBP reconstruction to fix the ratios between photoelectric and Compton scattering components of all image pixels. The reconstruction of a density image is easy to solve by a separable quadratic surrogate algorithm that is also applicable to the multi-material case. In addition, a spectrum binning method is introduced so that the full spectrum information is not required. The energy bins sizes and attenuations are optimized based on the true spectrum and object. With these approximations, the expected line integral values using only a few energy bins are very closed to the true polychromatic values. Thus both the problem size and computational demand caused by the large number of energy bins that are typically used to model a full spectrum are reduced. Simulation showed that three energy bins using the generalized spectrum binning method could provide an accurate approximation of the polychromatic X-ray signals. The average absolute error of the logarithmic detector signal is less than 0.003 for a 120 kVp spectrum. The proposed modified optimization problem and spectrum binning approach can effectively suppress beam hardening artifacts while providing low noise images.

  18. OpenCyto: an open source infrastructure for scalable, robust, reproducible, and automated, end-to-end flow cytometry data analysis.

    PubMed

    Finak, Greg; Frelinger, Jacob; Jiang, Wenxin; Newell, Evan W; Ramey, John; Davis, Mark M; Kalams, Spyros A; De Rosa, Stephen C; Gottardo, Raphael

    2014-08-01

    Flow cytometry is used increasingly in clinical research for cancer, immunology and vaccines. Technological advances in cytometry instrumentation are increasing the size and dimensionality of data sets, posing a challenge for traditional data management and analysis. Automated analysis methods, despite a general consensus of their importance to the future of the field, have been slow to gain widespread adoption. Here we present OpenCyto, a new BioConductor infrastructure and data analysis framework designed to lower the barrier of entry to automated flow data analysis algorithms by addressing key areas that we believe have held back wider adoption of automated approaches. OpenCyto supports end-to-end data analysis that is robust and reproducible while generating results that are easy to interpret. We have improved the existing, widely used core BioConductor flow cytometry infrastructure by allowing analysis to scale in a memory efficient manner to the large flow data sets that arise in clinical trials, and integrating domain-specific knowledge as part of the pipeline through the hierarchical relationships among cell populations. Pipelines are defined through a text-based csv file, limiting the need to write data-specific code, and are data agnostic to simplify repetitive analysis for core facilities. We demonstrate how to analyze two large cytometry data sets: an intracellular cytokine staining (ICS) data set from a published HIV vaccine trial focused on detecting rare, antigen-specific T-cell populations, where we identify a new subset of CD8 T-cells with a vaccine-regimen specific response that could not be identified through manual analysis, and a CyTOF T-cell phenotyping data set where a large staining panel and many cell populations are a challenge for traditional analysis. The substantial improvements to the core BioConductor flow cytometry packages give OpenCyto the potential for wide adoption. It can rapidly leverage new developments in computational

  19. RTEMP: Exploring an end-to-end, agnostic platform for multidisciplinary real-time analytics in the space physics community and beyond

    NASA Astrophysics Data System (ADS)

    Chaddock, D.; Donovan, E.; Spanswick, E.; Jackel, B. J.

    2014-12-01

    Large-scale, real-time, sensor-driven analytics are a highly effective set of tools in many research environments; however, the barrier to entry is expensive and the learning curve is steep. These systems need to operate efficiently from end to end, with the key aspects being data transmission, acquisition, management and organization, and retrieval. When building a generic multidisciplinary platform, acquisition and data management needs to be designed with scalability and flexibility as the primary focus. Additionally, in order to leverage current sensor web technologies, the integration of common sensor data standards (ie. SensorML and SWE Services) should be supported. Perhaps most important, researchers should be able to get started and integrate the platform into their set of research tools as easily and quickly as possible. The largest issue with current platforms is that the sensor data must be formed and described using the previously mentioned standards. As useful as these standards are for organizing data, they are cumbersome to adopt, often restrictive, and are required to be geospatially-driven. Our solution, RTEMP (Real-time Environment Monitoring Platform), is a real-time analytics platform with over ten years and an estimated two million dollars of investment. It has been developed for our continuously expanding requirements of operating and building remote sensors and supporting equipment for space physics research. A key benefit of our approach is RTEMP's ability to manage agnostic data. This allows data that flows through the system to be structured in any way that best addresses the needs of the sensor operators and data users, enabling extensive flexibility and streamlined development and research. Here we begin with an overview of RTEMP and how it is structured. Additionally, we will showcase the ways that we are using RTEMP and how it is being adopted by researchers in an increasingly broad range of other research fields. We will lay out a

  20. A novel PON based UMTS broadband wireless access network architecture with an algorithm to guarantee end to end QoS

    NASA Astrophysics Data System (ADS)

    Sana, Ajaz; Hussain, Shahab; Ali, Mohammed A.; Ahmed, Samir

    2007-09-01

    In this paper we proposes a novel Passive Optical Network (PON) based broadband wireless access network architecture to provide multimedia services (video telephony, video streaming, mobile TV, mobile emails etc) to mobile users. In the conventional wireless access networks, the base stations (Node B) and Radio Network Controllers (RNC) are connected by point to point T1/E1 lines (Iub interface). The T1/E1 lines are expensive and add up to operating costs. Also the resources (transceivers and T1/E1) are designed for peak hours traffic, so most of the time the dedicated resources are idle and wasted. Further more the T1/E1 lines are not capable of supporting bandwidth (BW) required by next generation wireless multimedia services proposed by High Speed Packet Access (HSPA, Rel.5) for Universal Mobile Telecommunications System (UMTS) and Evolution Data only (EV-DO) for Code Division Multiple Access 2000 (CDMA2000). The proposed PON based back haul can provide Giga bit data rates and Iub interface can be dynamically shared by Node Bs. The BW is dynamically allocated and the unused BW from lightly loaded Node Bs is assigned to heavily loaded Node Bs. We also propose a novel algorithm to provide end to end Quality of Service (QoS) (between RNC and user equipment).The algorithm provides QoS bounds in the wired domain as well as in wireless domain with compensation for wireless link errors. Because of the air interface there can be certain times when the user equipment (UE) is unable to communicate with Node B (usually referred to as link error). Since the link errors are bursty and location dependent. For a proposed approach, the scheduler at the Node B maps priorities and weights for QoS into wireless MAC. The compensations for errored links is provided by the swapping of services between the active users and the user data is divided into flows, with flows allowed to lag or lead. The algorithm guarantees (1)delay and throughput for error-free flows,(2)short term fairness

  1. OpenCyto: An Open Source Infrastructure for Scalable, Robust, Reproducible, and Automated, End-to-End Flow Cytometry Data Analysis

    PubMed Central

    Finak, Greg; Frelinger, Jacob; Jiang, Wenxin; Newell, Evan W.; Ramey, John; Davis, Mark M.; Kalams, Spyros A.; De Rosa, Stephen C.; Gottardo, Raphael

    2014-01-01

    Flow cytometry is used increasingly in clinical research for cancer, immunology and vaccines. Technological advances in cytometry instrumentation are increasing the size and dimensionality of data sets, posing a challenge for traditional data management and analysis. Automated analysis methods, despite a general consensus of their importance to the future of the field, have been slow to gain widespread adoption. Here we present OpenCyto, a new BioConductor infrastructure and data analysis framework designed to lower the barrier of entry to automated flow data analysis algorithms by addressing key areas that we believe have held back wider adoption of automated approaches. OpenCyto supports end-to-end data analysis that is robust and reproducible while generating results that are easy to interpret. We have improved the existing, widely used core BioConductor flow cytometry infrastructure by allowing analysis to scale in a memory efficient manner to the large flow data sets that arise in clinical trials, and integrating domain-specific knowledge as part of the pipeline through the hierarchical relationships among cell populations. Pipelines are defined through a text-based csv file, limiting the need to write data-specific code, and are data agnostic to simplify repetitive analysis for core facilities. We demonstrate how to analyze two large cytometry data sets: an intracellular cytokine staining (ICS) data set from a published HIV vaccine trial focused on detecting rare, antigen-specific T-cell populations, where we identify a new subset of CD8 T-cells with a vaccine-regimen specific response that could not be identified through manual analysis, and a CyTOF T-cell phenotyping data set where a large staining panel and many cell populations are a challenge for traditional analysis. The substantial improvements to the core BioConductor flow cytometry packages give OpenCyto the potential for wide adoption. It can rapidly leverage new developments in computational

  2. SU-E-J-25: End-To-End (E2E) Testing On TomoHDA System Using a Real Pig Head for Intracranial Radiosurgery

    SciTech Connect

    Corradini, N; Leick, M; Bonetti, M; Negretti, L

    2015-06-15

    Purpose: To determine the MVCT imaging uncertainty on the TomoHDA system for intracranial radiosurgery treatments. To determine the end-to-end (E2E) overall accuracy of the TomoHDA system for intracranial radiosurgery. Methods: A pig head was obtained from the butcher, cut coronally through the brain, and preserved in formaldehyde. The base of the head was fixed to a positioning plate allowing precise movement, i.e. translation and rotation, in all 6 axes. A repeatability test was performed on the pig head to determine uncertainty in the image bone registration algorithm. Furthermore, the test studied images with MVCT slice thicknesses of 1 and 3 mm in unison with differing scan lengths. A sensitivity test was performed to determine the registration algorithm’s ability to find the absolute position of known translations/rotations of the pig head. The algorithm’s ability to determine absolute position was compared against that of manual operators, i.e. a radiation therapist and radiation oncologist. Finally, E2E tests for intracranial radiosurgery were performed by measuring the delivered dose distributions within the pig head using Gafchromic films. Results: The repeatability test uncertainty was lowest for the MVCTs of 1-mm slice thickness, which measured less than 0.10 mm and 0.12 deg for all axes. For the sensitivity tests, the bone registration algorithm performed better than human eyes and a maximum difference of 0.3 mm and 0.4 deg was observed for the axes. E2E test results in absolute position difference measured 0.03 ± 0.21 mm in x-axis and 0.28 ± 0.18 mm in y-axis. A maximum difference of 0.32 and 0.66 mm was observed in x and y, respectively. The average peak dose difference between measured and calculated dose was 2.7 cGy or 0.4%. Conclusion: Our tests using a pig head phantom estimate the TomoHDA system to have a submillimeter overall accuracy for intracranial radiosurgery.

  3. Quantifying residual ionospheric errors in GNSS radio occultation bending angles based on ensembles of profiles from end-to-end simulations

    NASA Astrophysics Data System (ADS)

    Liu, C. L.; Kirchengast, G.; Zhang, K.; Norman, R.; Li, Y.; Zhang, S. C.; Fritzer, J.; Schwaerz, M.; Wu, S. Q.; Tan, Z. X.

    2015-07-01

    The radio occultation (RO) technique using signals from the Global Navigation Satellite System (GNSS), in particular from the Global Positioning System (GPS) so far, is currently widely used to observe the atmosphere for applications such as numerical weather prediction and global climate monitoring. The ionosphere is a major error source in RO measurements at stratospheric altitudes, and a linear ionospheric correction of dual-frequency RO bending angles is commonly used to remove the first-order ionospheric effect. However, the residual ionospheric error (RIE) can still be significant so that it needs to be further mitigated for high-accuracy applications, especially above about 30 km altitude where the RIE is most relevant compared to the magnitude of the neutral atmospheric bending angle. Quantification and careful analyses for better understanding of the RIE is therefore important for enabling benchmark-quality stratospheric RO retrievals. Here we present such an analysis of bending angle RIEs covering the stratosphere and mesosphere, using quasi-realistic end-to-end simulations for a full-day ensemble of RO events. Based on the ensemble simulations we assessed the variation of bending angle RIEs, both biases and standard deviations, with solar activity, latitudinal region and with or without the assumption of ionospheric spherical symmetry and co-existing observing system errors. We find that the bending angle RIE biases in the upper stratosphere and mesosphere, and in all latitudinal zones from low to high latitudes, have a clear negative tendency and a magnitude increasing with solar activity, which is in line with recent empirical studies based on real RO data although we find smaller bias magnitudes, deserving further study in the future. The maximum RIE biases are found at low latitudes during daytime, where they amount to within -0.03 to -0.05 μrad, the smallest at high latitudes (0 to -0.01 μrad; quiet space weather and winter conditions

  4. Quantifying residual ionospheric errors in GNSS radio occultation bending angles based on ensembles of profiles from end-to-end simulations

    NASA Astrophysics Data System (ADS)

    Liu, C. L.; Kirchengast, G.; Zhang, K.; Norman, R.; Li, Y.; Zhang, S. C.; Fritzer, J.; Schwaerz, M.; Wu, S. Q.; Tan, Z. X.

    2015-01-01

    The radio occultation (RO) technique using signals from the Global Navigation Satellite System (GNSS), in particular from the Global Positioning System (GPS) so far, is meanwhile widely used to observe the atmosphere for applications such as numerical weather prediction and global climate monitoring. The ionosphere is a major error source in RO measurements at stratospheric altitudes and a linear ionospheric correction of dual-frequency RO bending angles is commonly used to remove the first-order ionospheric effect. However, the residual ionopheric error (RIE) can still be significant so that it needs to be further mitigated for high accuracy applications, especially above about 30 km altitude where the RIE is most relevant compared to the magnitude of the neutral atmospheric bending angle. Quantification and careful analyses for better understanding of the RIE is therefore important towards enabling benchmark-quality stratospheric RO retrievals. Here we present such an analysis of bending angle RIEs covering the stratosphere and mesosphere, using quasi-realistic end-to-end simulations for a full-day ensemble of RO events. Based on the ensemble simulations we assessed the variation of bending angle RIEs, both biases and SDs, with solar activity, latitudinal region, and with or without the assumption of ionospheric spherical symmetry and of co-existing observing system errors. We find that the bending angle RIE biases in the upper stratosphere and mesosphere, and in all latitudinal zones from low- to high-latitudes, have a clear negative tendency and a magnitude increasing with solar activity, in line with recent empirical studies based on real RO data. The maximum RIE biases are found at low latitudes during daytime, where they amount to with in -0.03 to -0.05 μrad, the smallest at high latitudes (0 to -0.01 μrad; quiet space weather and winter conditions). Ionospheric spherical symmetry or asymmetries about the RO event location have only a minor influence on

  5. SU-E-J-194: Dynamic Tumor Tracking End-To-End Testing Using a 4D Thorax Phantom and EBT3 Films

    SciTech Connect

    Su, Z; Wu, J; Li, Z; Mamalui-Hunter, M

    2014-06-01

    Purpose: To quantify the Vero linac dosimetric accuracy of the tumor dynamic tracking treatment using EBT3 film embedded in a 4D thorax phantom. Methods: A dynamic thorax phantom with tissue equivalent materials and a film insert were used in this study. The thorax phantom was scanned in 4DCT mode with a viscoil embedded in its film insert composed of lung equivalent material. Dynamic tracking planning was performed using the 50% phase CT set with 5 conformal beams at gantry angles of 330, 15, 60, 105 and 150 degrees. Each field is a 3cm by 3cm square centered at viscoil since there was no solid mass target. Total 3 different 1–2cos4 motion profiles were used with varied motion magnitude and cycle frequency. Before treatment plan irradiation, a 4D motion model of the target was established using a series of acquired fluoroscopic images and infrared markers motion positions. During irradiation, fluoroscopic image monitoring viscoil motion was performed to verify model validity. The irradiated films were scanned and the dose maps were compared to the planned Monte Carlo dose distributions. Gamma analyses using 3%–3mm, 2%–3mm, 3%–2mm, 2%–2mm criteria were performed and presented. Results: For each motion pattern, a 4D motion model was built successfully and the target tracking performance was verified with fluoroscopic monitoring of the viscoil motion and its model predicted locations. The film gamma analysis showed the average pass rates among the 3 motion profiles are 98.14%, 96.2%, 91.3% and 85.61% for 3%–3mm, 2%–3mm, 3%–2mm, 2%–2mm criteria. Conclusion: Target dynamic tracking was performed using patient-like breathing patterns in a 4D thorax phantom with EBT3 film insert and a viscoil. There was excellent agreement between acquired and planned dose distributions for all three target motion patterns. This study performed end-to-end testing and verified the treatment accuracy of tumor dynamic tracking.

  6. Reconstruction of digital spectrum from periodic nonuniformly sampled signals in offset linear canonical transform domain

    NASA Astrophysics Data System (ADS)

    Xu, Shuiqing; Chai, Yi; Hu, Youqiang; Jiang, Congmei; Li, Yi

    2015-08-01

    Periodic nonuniform sampling is a special case of nonuniform sampling. It arises in a broad range of applications due to imperfect timebase or random events. As the offset linear canonical transform (OLCT) has been shown to be a powerful tool for optics and signal processing, it is worthwhile and interesting to explore the spectral analysis and reconstruction for periodic nonuniformly sampled signals in the OLCT domain. In this paper, we address the problem of spectral analysis and reconstruction for periodic nonuniformly sampled signals associated with the OLCT. Firstly, detailed spectral analysis of periodic nonuniformly sampled one-dimensional signals has been performed. By applying the results, a relationship between the discrete and continuous spectrum has been deduced, and a method to reconstruct the digital spectrum from periodic nonuniformly sampled signals in one-dimensional case has been proposed. Then, we extend that theories to the two-dimensional case. Finally, the simulation results are presented to show the advantage and effectiveness of the methods. Detailed spectral analysis of periodic nonuniformly sampled one-dimensional signals in the OLCT domain have been performed. A relationship between the discrete and continuous OLCT spectrum has been deduced. A method to reconstruct the digital spectrum from periodic nonuniformly sampled signals in one-dimensional case has been proposed. All the theories have been extended to the two-dimensional case.

  7. On minimally parametric primordial power spectrum reconstruction and the evidence for a red tilt

    SciTech Connect

    Verde, Licia; Peiris, Hiranya E-mail: lverde@astro.princeton.edu

    2008-07-15

    The latest cosmological data seem to indicate a significant deviation from scale invariance of the primordial power spectrum when parameterized either by a power law or by a spectral index with non-zero 'running'. This deviation, by itself, serves as a powerful tool for discriminating among theories for the origin of cosmological structures such as inflationary models. Here, we use a minimally parametric smoothing spline technique to reconstruct the shape of the primordial power spectrum. This technique is well suited to searching for smooth features in the primordial power spectrum such as deviations from scale invariance or a running spectral index, although it would recover sharp features of high statistical significance. We use the WMAP three-year results in combination with data from a suite of higher resolution cosmic microwave background experiments (including the latest ACBAR 2008 release), as well as large-scale structure data from SDSS and 2dFGRS. We employ cross-validation to assess, using the data themselves, the optimal amount of smoothness in the primordial power spectrum consistent with the data. This minimally parametric reconstruction supports the evidence for a power law primordial power spectrum with a red tilt, but not for deviations from a power law power spectrum. Smooth variations in the primordial power spectrum are not significantly degenerate with the other cosmological parameters.

  8. A Vehicle Management End-to-End Testing and Analysis Platform for Validation of Mission and Fault Management Algorithms to Reduce Risk for NASA's Space Launch System

    NASA Technical Reports Server (NTRS)

    Trevino, Luis; Johnson, Stephen B.; Patterson, Jonathan; Teare, David

    2015-01-01

    The development of the Space Launch System (SLS) launch vehicle requires cross discipline teams with extensive knowledge of launch vehicle subsystems, information theory, and autonomous algorithms dealing with all operations from pre-launch through on orbit operations. The characteristics of these systems must be matched with the autonomous algorithm monitoring and mitigation capabilities for accurate control and response to abnormal conditions throughout all vehicle mission flight phases, including precipitating safing actions and crew aborts. This presents a large complex systems engineering challenge being addressed in part by focusing on the specific subsystems handling of off-nominal mission and fault tolerance. Using traditional model based system and software engineering design principles from the Unified Modeling Language (UML), the Mission and Fault Management (M&FM) algorithms are crafted and vetted in specialized Integrated Development Teams composed of multiple development disciplines. NASA also has formed an M&FM team for addressing fault management early in the development lifecycle. This team has developed a dedicated Vehicle Management End-to-End Testbed (VMET) that integrates specific M&FM algorithms, specialized nominal and off-nominal test cases, and vendor-supplied physics-based launch vehicle subsystem models. The flexibility of VMET enables thorough testing of the M&FM algorithms by providing configurable suites of both nominal and off-nominal test cases to validate the algorithms utilizing actual subsystem models. The intent is to validate the algorithms and substantiate them with performance baselines for each of the vehicle subsystems in an independent platform exterior to flight software test processes. In any software development process there is inherent risk in the interpretation and implementation of concepts into software through requirements and test processes. Risk reduction is addressed by working with other organizations such as S

  9. Micro-ARES, an electric-field sensor for ExoMars 2016: Electric fields modelling, sensitivity evaluations and end-to-end tests.

    NASA Astrophysics Data System (ADS)

    Déprez, Grégoire; Montmessin, Franck; Witasse, Olivier; Lapauw, Laurent; Vivat, Francis; Abbaki, Sadok; Granier, Philippe; Moirin, David; Trautner, Roland; Hassen-Khodja, Rafik; d'Almeida, Éric; Chardenal, Laurent; Berthelier, Jean-Jacques; Esposito, Francesca; Debei, Stefano; Rafkin, Scott; Barth, Erika

    2014-05-01

    Earth and transposed to the Martian atmospheric parameters. Knowing the expected electric fields and simulating them, the next step in order to evaluate the performance of the instrument is to determine its sensitivity by modelling the response of the instrument. The last step is to confront the model of the instrument, and the expected results for a given signal with the effective outputs of the electric board with the same signal as an input. To achieve this end-to-end test, we use a signal generator followed by an electrical circuit reproducing the electrode behaviour in the Martian environment, in order to inject a realistic electric signal in the processing board and finally compare the produced formatted data with the expected ones.

  10. A Vehicle Management End-to-End Testing and Analysis Platform for Validation of Mission and Fault Management Algorithms to Reduce Risk for NASA's Space Launch System

    NASA Technical Reports Server (NTRS)

    Trevino, Luis; Patterson, Jonathan; Teare, David; Johnson, Stephen

    2015-01-01

    integrates specific M&FM algorithms, specialized nominal and off-nominal test cases, and vendor-supplied physics-based launch vehicle subsystem models. Additionally, the team has developed processes for implementing and validating these algorithms for concept validation and risk reduction for the SLS program. The flexibility of the Vehicle Management End-to-end Testbed (VMET) enables thorough testing of the M&FM algorithms by providing configurable suites of both nominal and off-nominal test cases to validate the developed algorithms utilizing actual subsystem models such as MPS. The intent of VMET is to validate the M&FM algorithms and substantiate them with performance baselines for each of the target vehicle subsystems in an independent platform exterior to the flight software development infrastructure and its related testing entities. In any software development process there is inherent risk in the interpretation and implementation of concepts into software through requirements and test cases into flight software compounded with potential human errors throughout the development lifecycle. Risk reduction is addressed by the M&FM analysis group working with other organizations such as S&MA, Structures and Environments, GNC, Orion, the Crew Office, Flight Operations, and Ground Operations by assessing performance of the M&FM algorithms in terms of their ability to reduce Loss of Mission and Loss of Crew probabilities. In addition, through state machine and diagnostic modeling, analysis efforts investigate a broader suite of failure effects and associated detection and responses that can be tested in VMET to ensure that failures can be detected, and confirm that responses do not create additional risks or cause undesired states through interactive dynamic effects with other algorithms and systems. VMET further contributes to risk reduction by prototyping and exercising the M&FM algorithms early in their implementation and without any inherent hindrances such as meeting FSW

  11. A Vehicle Management End-to-End Testing and Analysis Platform for Validation of Mission and Fault Management Algorithms to Reduce Risk for NASAs Space Launch System

    NASA Technical Reports Server (NTRS)

    Trevino, Luis; Johnson, Stephen B.; Patterson, Jonathan; Teare, David

    2015-01-01

    The engineering development of the National Aeronautics and Space Administration's (NASA) new Space Launch System (SLS) requires cross discipline teams with extensive knowledge of launch vehicle subsystems, information theory, and autonomous algorithms dealing with all operations from pre-launch through on orbit operations. The nominal and off-nominal characteristics of SLS's elements and subsystems must be understood and matched with the autonomous algorithm monitoring and mitigation capabilities for accurate control and response to abnormal conditions throughout all vehicle mission flight phases, including precipitating safing actions and crew aborts. This presents a large and complex systems engineering challenge, which is being addressed in part by focusing on the specific subsystems involved in the handling of off-nominal mission and fault tolerance with response management. Using traditional model-based system and software engineering design principles from the Unified Modeling Language (UML) and Systems Modeling Language (SysML), the Mission and Fault Management (M&FM) algorithms for the vehicle are crafted and vetted in Integrated Development Teams (IDTs) composed of multiple development disciplines such as Systems Engineering (SE), Flight Software (FSW), Safety and Mission Assurance (S&MA) and the major subsystems and vehicle elements such as Main Propulsion Systems (MPS), boosters, avionics, Guidance, Navigation, and Control (GNC), Thrust Vector Control (TVC), and liquid engines. These model-based algorithms and their development lifecycle from inception through FSW certification are an important focus of SLS's development effort to further ensure reliable detection and response to off-nominal vehicle states during all phases of vehicle operation from pre-launch through end of flight. To test and validate these M&FM algorithms a dedicated test-bed was developed for full Vehicle Management End-to-End Testing (VMET). For addressing fault management (FM

  12. SU-E-T-109: Development of An End-To-End Test for the Varian TrueBeamtm with a Novel Multiple-Dosimetric Modality H and N Phantom

    SciTech Connect

    Zakjevskii, V; Knill, C; Rakowski, J; Snyder, M

    2014-06-01

    Purpose: To develop a comprehensive end-to-end test for Varian's TrueBeam linear accelerator for head and neck IMRT using a custom phantom designed to utilize multiple dosimetry devices. Methods: The initial end-to-end test and custom H and N phantom were designed to yield maximum information in anatomical regions significant to H and N plans with respect to: i) geometric accuracy, ii) dosimetric accuracy, and iii) treatment reproducibility. The phantom was designed in collaboration with Integrated Medical Technologies. A CT image was taken with a 1mm slice thickness. The CT was imported into Varian's Eclipse treatment planning system, where OARs and the PTV were contoured. A clinical template was used to create an eight field static gantry angle IMRT plan. After optimization, dose was calculated using the Analytic Anisotropic Algorithm with inhomogeneity correction. Plans were delivered with a TrueBeam equipped with a high definition MLC. Preliminary end-to-end results were measured using film and ion chambers. Ion chamber dose measurements were compared to the TPS. Films were analyzed with FilmQAPro using composite gamma index. Results: Film analysis for the initial end-to-end plan with a geometrically simple PTV showed average gamma pass rates >99% with a passing criterion of 3% / 3mm. Film analysis of a plan with a more realistic, ie. complex, PTV yielded pass rates >99% in clinically important regions containing the PTV, spinal cord and parotid glands. Ion chamber measurements were on average within 1.21% of calculated dose for both plans. Conclusion: trials have demonstrated that our end-to-end testing methods provide baseline values for the dosimetric and geometric accuracy of Varian's TrueBeam system.

  13. Monte Carlo simulations for 20 MV X-ray spectrum reconstruction of a linear induction accelerator

    NASA Astrophysics Data System (ADS)

    Wang, Yi; Li, Qin; Jiang, Xiao-Guo

    2012-09-01

    To study the spectrum reconstruction of the 20 MV X-ray generated by the Dragon-I linear induction accelerator, the Monte Carlo method is applied to simulate the attenuations of the X-ray in the attenuators of different thicknesses and thus provide the transmission data. As is known, the spectrum estimation from transmission data is an ill-conditioned problem. The method based on iterative perturbations is employed to derive the X-ray spectra, where initial guesses are used to start the process. This algorithm takes into account not only the minimization of the differences between the measured and the calculated transmissions but also the smoothness feature of the spectrum function. In this work, various filter materials are put to use as the attenuator, and the condition for an accurate and robust solution of the X-ray spectrum calculation is demonstrated. The influences of the scattering photons within different intervals of emergence angle on the X-ray spectrum reconstruction are also analyzed.

  14. Reconstruction of the Galactic Cosmic ray Spectrum during the June 2015 Forbush decrease

    NASA Astrophysics Data System (ADS)

    Santiago, Alberto; Lara, Alejandro

    2016-07-01

    During the final week of June 2015, a Forbush decrease was observed by different detectors around the world. We have used data from Neutron Monitors of the North-west University, South Africa, and a force free model to reconstruct the variations of the primary spectrum of the galactic cosmic rays during this event. The validity of our method was confirmed by convolving the computed spectrum with the appropriate Yield function, to reproduce the observations of different Neutron Monitors reported in the Neutron Monitor database. We found a very good agreement between the observed and computed data. We present the method, the results and its possible application to different cosmic ray detectors.

  15. Reconstruction of crystal band structure from the power spectrum of strong-field generated high harmonics

    NASA Astrophysics Data System (ADS)

    Wang, Chang-Ming; Ho, Tak-San; Chu, Shih-I.

    2016-05-01

    The study of high harmonic generation in solid driven by intense laser fields is a subject of much current interest. Recently we introduce a new optimization method to directly reconstruct the band structure of the crystal from the power spectrum of strong-field generated high harmonics. Without loss of generality, the reconstruction is formulated for a one-dimensional single band model as a minimization problem and solved by a derivative-free unconstrained optimization algorithm-NEWUOA. The method can be readily generalized to treat multi-band problems. Numerical simulations are presented to demonstrate the applicability of the method, and the reconstructed band structure is found to be in excellent agreement with the exact one. It is also shown that our optimization method remains robust and efficient even starting from the poorly guessed band structure.

  16. Polychromatic sparse image reconstruction and mass attenuation spectrum estimation via B-spline basis function expansion

    NASA Astrophysics Data System (ADS)

    Gu, Renliang; Dogandžić, Aleksandar

    2015-03-01

    We develop a sparse image reconstruction method for polychromatic computed tomography (CT) measurements under the blind scenario where the material of the inspected object and the incident energy spectrum are unknown. To obtain a parsimonious measurement model parameterization, we first rewrite the measurement equation using our mass-attenuation parameterization, which has the Laplace integral form. The unknown mass-attenuation spectrum is expanded into basis functions using a B-spline basis of order one. We develop a block coordinate-descent algorithm for constrained minimization of a penalized negative log-likelihood function, where constraints and penalty terms ensure nonnegativity of the spline coefficients and sparsity of the density map image in the wavelet domain. This algorithm alternates between a Nesterov's proximal-gradient step for estimating the density map image and an active-set step for estimating the incident spectrum parameters. Numerical simulations demonstrate the performance of the proposed scheme.

  17. Polychromatic sparse image reconstruction and mass attenuation spectrum estimation via B-spline basis function expansion

    SciTech Connect

    Gu, Renliang E-mail: ald@iastate.edu; Dogandžić, Aleksandar E-mail: ald@iastate.edu

    2015-03-31

    We develop a sparse image reconstruction method for polychromatic computed tomography (CT) measurements under the blind scenario where the material of the inspected object and the incident energy spectrum are unknown. To obtain a parsimonious measurement model parameterization, we first rewrite the measurement equation using our mass-attenuation parameterization, which has the Laplace integral form. The unknown mass-attenuation spectrum is expanded into basis functions using a B-spline basis of order one. We develop a block coordinate-descent algorithm for constrained minimization of a penalized negative log-likelihood function, where constraints and penalty terms ensure nonnegativity of the spline coefficients and sparsity of the density map image in the wavelet domain. This algorithm alternates between a Nesterov’s proximal-gradient step for estimating the density map image and an active-set step for estimating the incident spectrum parameters. Numerical simulations demonstrate the performance of the proposed scheme.

  18. [A case of tracheo-bronchial stenosis after extended end-to-end aortic arch anastomosis for interrupted aortic arch treated with suspension of the ascending artery and pulmonary artery].

    PubMed

    Watanabe, T; Hoshino, S; Iwaya, F; Igari, T; Ono, T; Takahashi, K

    2001-02-01

    A 9-day-old boy had pulmonary artery banding and extended end-to-end aortic arch anastomosis for ventricular septal defect (VSD) and type A interrupted aortic arch. Severe dyspnea gradually developed. At 3 months of age, intracardiac repair of VSD was performed. Weaning from the ventilator was difficult. Endoscopic examination and chest CT revealed stenosis of the right and left main bronchi and compression of tracheal bifurcation and the right and left main bronchi by the ascending aorta and pulmonary artery. Suspension of the ascending aorta and pulmonary artery was performed 15 days after VSD closure. Nine days after this procedure, the patient was weaned from respirator. Postoperative course was uneventful. Bronchial stenosis may be caused from extended end-to-end aortic arch anastomosis. PMID:11211771

  19. Red, Straight, no bends: primordial power spectrum reconstruction from CMB and large-scale structure

    NASA Astrophysics Data System (ADS)

    Ravenni, Andrea; Verde, Licia; Cuesta, Antonio J.

    2016-08-01

    We present a minimally parametric, model independent reconstruction of the shape of the primordial power spectrum. Our smoothing spline technique is well-suited to search for smooth features such as deviations from scale invariance, and deviations from a power law such as running of the spectral index or small-scale power suppression. We use a comprehensive set of the state-of the art cosmological data: Planck observations of the temperature and polarisation anisotropies of the cosmic microwave background, WiggleZ and Sloan Digital Sky Survey Data Release 7 galaxy power spectra and the Canada-France-Hawaii Lensing Survey correlation function. This reconstruction strongly supports the evidence for a power law primordial power spectrum with a red tilt and disfavours deviations from a power law power spectrum including small-scale power suppression such as that induced by significantly massive neutrinos. This offers a powerful confirmation of the inflationary paradigm, justifying the adoption of the inflationary prior in cosmological analyses.

  20. Reconstruction of a nonminimal coupling theory with scale-invariant power spectrum

    SciTech Connect

    Qiu, Taotao

    2012-06-01

    A nonminimal coupling single scalar field theory, when transformed from Jordan frame to Einstein frame, can act like a minimal coupling one. Making use of this property, we investigate how a nonminimal coupling theory with scale-invariant power spectrum could be reconstructed from its minimal coupling counterpart, which can be applied in the early universe. Thanks to the coupling to gravity, the equation of state of our universe for a scale-invariant power spectrum can be relaxed, and the relation between the parameters in the action can be obtained. This approach also provides a means to address the Big-Bang puzzles and anisotropy problem in the nonminimal coupling model within Jordan frame. Due to the equivalence between the two frames, one may be able to find models that are free of the horizon, flatness, singularity as well as anisotropy problems.

  1. Optimizing end-to-end system performance for millimeter and submillimeter spectroscopy of protostars : wideband heterodyne receivers and sideband-deconvolution techniques for rapid molecular-line surveys

    NASA Astrophysics Data System (ADS)

    Sumner, Matthew Casey

    signal and broader tuning range of the Gunn continue to make it the preferred choice. The receiver and high-resolution spectrometer system were brought into a fully operational state late in 2007, when they were used to perform unbiased molecular-line surveys of several galactic sources, including the Orion KL hot core and a position in the L1157 outflow. In order to analyze these data, a new data pipeline was needed to deconvolve the double-sideband signals from the receiver and to model the molecular spectra. A highly automated sideband-deconvolution system has been created, and spectral-analysis tools are currently being developed. The sideband deconvolution relies on chi-square minimization to determine the optimal single-sideband spectrum in the presence of unknown sideband-gain imbalances and spectral baselines. Analytic results are presented for several different methods of approaching the problem, including direct optimization, nonlinear root finding, and a hybrid approach that utilizes a two-stage process to separate out the relatively weak nonlinearities so that the majority of the parameters can be found with a fast linear solver. Analytic derivations of the Jacobian matrices for all three cases are presented, along with a new Mathematica utility that enables the calculation of arbitrary gradients. The direct-optimization method has been incorporated into software, along with a spectral simulation engine that allows different deconvolution scenarios to be tested. The software has been validated through the deconvolution of simulated data sets, and initial results from L1157 and Orion are presented. Both surveys demonstrate the power of the wideband receivers and improved data pipeline to enable exciting scientific studies. The L1157 survey was completed in only 20 hours of telescope time and offers moderate sensitivity over a > 50-GHz range, from 220 GHz to approximately 270 or 280 GHz. The speed with which this survey was completed implies that the new

  2. Reconstruction of broad features in the primordial spectrum and inflaton potential from Planck

    SciTech Connect

    Hazra, Dhiraj Kumar; Shafieloo, Arman; Smoot, George F. E-mail: arman@apctp.org

    2013-12-01

    With the recently published Cosmic Microwave Background data from Planck we address the optimized binning of the primordial power spectrum. As an important modification to the usual binning of the primordial spectrum, along with the spectral amplitude of the bins, we allow the position of the bins also to vary. This technique enables us to address the location of the possible broad physical features in the primordial spectrum with relatively smaller number of bins compared to the analysis performed earlier. This approach is in fact a reconstruction method looking for broad features in the primordial spectrum and avoiding fitting noise in the data. Performing Markov Chain Monte Carlo analysis we present samples of the allowed primordial spectra with broad features consistent with Planck data. To test how realistic it is to have step-like features in primordial spectrum we revisit an inflationary model, proposed by A. A. Starobinsky which can address the similar features obtained from the binning of the spectrum. Using the publicly available code BINGO, we numerically calculate the local f{sub NL} for this model in equilateral and arbitrary triangular configurations of wavevectors and show that the obtained non-Gaussianity for this model is consistent with Planck results. In this paper we have also considered different spectral tilts at different bins to identify the cosmological scale that the spectral index needs to have a red tilt and it is interesting to report that spectral index cannot be well constrained up to k ≈ 0.01Mpc{sup −1}.

  3. [A Method to Reconstruct Surface Reflectance Spectrum from Multispectral Image Based on Canopy Radiation Transfer Model].

    PubMed

    Zhao, Yong-guang; Ma, Ling-ling; Li, Chuan-rong; Zhu, Xiao-hua; Tang, Ling-li

    2015-07-01

    Due to the lack of enough spectral bands for multi-spectral sensor, it is difficult to reconstruct surface retlectance spectrum from finite spectral information acquired by multi-spectral instrument. Here, taking into full account of the heterogeneity of pixel from remote sensing image, a method is proposed to simulate hyperspectral data from multispectral data based on canopy radiation transfer model. This method first assumes the mixed pixels contain two types of land cover, i.e., vegetation and soil. The sensitive parameters of Soil-Leaf-Canopy (SLC) model and a soil ratio factor were retrieved from multi-spectral data based on Look-Up Table (LUT) technology. Then, by combined with a soil ratio factor, all the parameters were input into the SLC model to simulate the surface reflectance spectrum from 400 to 2 400 nm. Taking Landsat Enhanced Thematic Mapper Plus (ETM+) image as reference image, the surface reflectance spectrum was simulated. The simulated reflectance spectrum revealed different feature information of different surface types. To test the performance of this method, the simulated reflectance spectrum was convolved with the Landsat ETM + spectral response curves and Moderate Resolution Imaging Spectrometer (MODIS) spectral response curves to obtain the simulated Landsat ETM+ and MODIS image. Finally, the simulated Landsat ETM+ and MODIS images were compared with the observed Landsat ETM+ and MODIS images. The results generally showed high correction coefficients (Landsat: 0.90-0.99, MODIS: 0.74-0.85) between most simulated bands and observed bands and indicated that the simulated reflectance spectrum was well simulated and reliable. PMID:26717721

  4. Reconstruction of a broadband spectrum of Alfvénic fluctuations

    SciTech Connect

    Viñas, Adolfo F; Moya, Pablo S.; Maneva, Yana G.; Araneda, Jaime A.

    2014-05-10

    Alfvénic fluctuations in the solar wind exhibit a high degree of velocities and magnetic field correlations consistent with Alfvén waves propagating away and toward the Sun. Two remarkable properties of these fluctuations are the tendencies to have either positive or negative magnetic helicity (–1 ≤ σ {sub m} ≤ +1) associated with either left- or right- topological handedness of the fluctuations and to have a constant magnetic field magnitude. This paper provides, for the first time, a theoretical framework for reconstructing both the magnetic and velocity field fluctuations with a divergence-free magnetic field, with any specified power spectral index and normalized magnetic- and cross-helicity spectrum field fluctuations for any plasma species. The spectrum is constructed in the Fourier domain by imposing two conditions—a divergence-free magnetic field and the preservation of the sense of magnetic helicity in both spaces—as well as using Parseval's theorem for the conservation of energy between configuration and Fourier spaces. Applications to the one-dimensional spatial Alfvénic propagation are presented. The theoretical construction is in agreement with typical time series and power spectra properties observed in the solar wind. The theoretical ideas presented in this spectral reconstruction provide a foundation for more realistic simulations of plasma waves, solar wind turbulence, and the propagation of energetic particles in such fluctuating fields.

  5. [Research on an Equal Wavelength Spectrum Reconstruction Method of Interference Imaging Spectrometer].

    PubMed

    Xie, Pei-yue; Yang, Jian-feng; Xue, Bin; Lü, Juan; He, Ying-hong; Li, Ting; Ma, Xiao-long

    2016-03-01

    Interference imaging spectrometer is one of the most important equipments of Chang'E 1 satellite, which is applied to analysis the material composition and its distribution of the surface on the moon. At present, the spectral resolution of level 2B scientific data obtained by existing methods is 325 cm(-1). If we use the description way of wavelength resolution, various spectrum is different: the first band is 7.6 nm, the last band is 29 nm, which introduces two questions: (1) the spectral resolution description way mismatch with the way of ground spectral library used for calibration and comparison; (2) The signal-to-noise ratio of the spectra in the shortwave band is low due to the signal entering narrow band is little. This paper discussed the relationship between wavelength resolution and cut-off function based on the reconstruction model of CE-1 interference imaging spectrometer. It proposed an adjustable cut-off function changing with wavelength or wavelength resolution, while selected the appropriate Sinc function as apodization to realize the reconstruction of arbitrary specified wavelength resolution in the band coverage. Then we used this method to CE-1 on orbit 0B data to get a spectral image of 29 nm wavelength resolution. Finally, by using the signal-to-noise ratio, principal component analysis and unsupervised classification method on the reconstruction results with 2 grade science data from ground application system for comparison, the results showed that: signal-to-noise ratio of the shortwave band increased about 4 times, and the average increased about 2.4 times, the classification based on the spectrum was consistent, and the quality of the data was greatly improved. So, EWSR method has the advantages that: (1) in the case of keeping spectral information steadiness, it can improve the signal-to-noise ratio of shortwave band spectrum though sacrificed part of spectral resolution; (2) it can achieve the spectral data reconstruction which can set

  6. Demonstration of end-to-end cloud-DSL with a PON-based fronthaul supporting 5.76-Gb/s throughput with 48 eCDMA-encoded 1024-QAM discrete multi-tone signals.

    PubMed

    Fang, Liming; Zhou, Lei; Liu, Xiang; Zhang, Xiaofeng; Sui, Meng; Effenberger, Frank; Zhou, Jun

    2015-05-18

    We experimentally demonstrate an end-to-end ultra-broadband cloud-DSL network using passive optical network (PON) based fronthaul with electronic code-division-multiple-access (eCDMA) encoding and decoding. Forty-eight signals that are compliant with the very-high-bit-rate digital subscriber line 2 (VDSL2) standard are transmitted with a record throughput of 5.76 Gb/s over a hybrid link consisting of a 20-km standard single-mode fiber and a 100-m twisted pair. PMID:26074597

  7. Reconstruction of the primordial power spectrum of curvature perturbations using multiple data sets

    SciTech Connect

    Hunt, Paul; Sarkar, Subir E-mail: s.sarkar@physics.ox.ac.uk

    2014-01-01

    Detailed knowledge of the primordial power spectrum of curvature perturbations is essential both in order to elucidate the physical mechanism ('inflation') which generated it, and for estimating the cosmological parameters from observations of the cosmic microwave background and large-scale structure. Hence it ought to be extracted from such data in a model-independent manner, however this is difficult because relevant cosmological observables are given by a convolution of the primordial perturbations with some smoothing kernel which depends on both the assumed world model and the matter content of the universe. Moreover the deconvolution problem is ill-conditioned so a regularisation scheme must be employed to control error propagation. We demonstrate that 'Tikhonov regularisation' can robustly reconstruct the primordial spectrum from multiple cosmological data sets, a significant advantage being that both its uncertainty and resolution are then quantified. Using Monte Carlo simulations we investigate several regularisation parameter selection methods and find that generalised cross-validation and Mallow's C{sub p} method give optimal results. We apply our inversion procedure to data from the Wilkinson Microwave Anisotropy Probe, other ground-based small angular scale CMB experiments, and the Sloan Digital Sky Survey. The reconstructed spectrum (assuming the standard ΛCDM cosmology) is not scale-free but has an infrared cutoff at k∼<5 × 10{sup −4} Mpc{sup −1} (due to the anomalously low CMB quadrupole) and several features with ∼ 2σ significance at k/Mpc{sup −1} ∼ 0.0013–0.0025, 0.0362–0.0402 and 0.051–0.056, reflecting the 'WMAP glitches'. To test whether these are indeed real will require more accurate data, such as from the Planck satellite and new ground-based experiments.

  8. Reconstruction of the primordial power spectrum of curvature perturbations using multiple data sets

    NASA Astrophysics Data System (ADS)

    Hunt, Paul; Sarkar, Subir

    2014-01-01

    Detailed knowledge of the primordial power spectrum of curvature perturbations is essential both in order to elucidate the physical mechanism (`inflation') which generated it, and for estimating the cosmological parameters from observations of the cosmic microwave background and large-scale structure. Hence it ought to be extracted from such data in a model-independent manner, however this is difficult because relevant cosmological observables are given by a convolution of the primordial perturbations with some smoothing kernel which depends on both the assumed world model and the matter content of the universe. Moreover the deconvolution problem is ill-conditioned so a regularisation scheme must be employed to control error propagation. We demonstrate that `Tikhonov regularisation' can robustly reconstruct the primordial spectrum from multiple cosmological data sets, a significant advantage being that both its uncertainty and resolution are then quantified. Using Monte Carlo simulations we investigate several regularisation parameter selection methods and find that generalised cross-validation and Mallow's Cp method give optimal results. We apply our inversion procedure to data from the Wilkinson Microwave Anisotropy Probe, other ground-based small angular scale CMB experiments, and the Sloan Digital Sky Survey. The reconstructed spectrum (assuming the standard ΛCDM cosmology) is not scale-free but has an infrared cutoff at klesssim5 × 10-4 Mpc-1 (due to the anomalously low CMB quadrupole) and several features with ~ 2σ significance at k/Mpc-1 ~ 0.0013-0.0025, 0.0362-0.0402 and 0.051-0.056, reflecting the `WMAP glitches'. To test whether these are indeed real will require more accurate data, such as from the Planck satellite and new ground-based experiments.

  9. End-to-end image quality assessment

    NASA Astrophysics Data System (ADS)

    Raventos, Joaquin

    2012-05-01

    An innovative computerized benchmarking approach (US Patent pending Sep 2011) based on extensive application of photometry, geometrical optics, and digital media using a randomized target, for a standard observer to assess the image quality of video imaging systems, at different day time, and low-light luminance levels. It takes into account, the target's contrast and color characteristics, as well as the observer's visual acuity and dynamic response. This includes human vision as part of the "extended video imaging system" (EVIS), and allows image quality assessment by several standard observers simultaneously.

  10. Pilot End-to-End Calibration Results

    NASA Astrophysics Data System (ADS)

    Misawa, R.; Bernard, J.-Ph.; Ade, P.; Andre, Y.; de Bernardis, P.; Bautista, L.; Boulade, O.; Bousquet, F.; Bouzit, M.; Bray, N.; Brysbaert, C.; Buttice, V.; Caillat, A.; Chaigneau, M.; Charra, M.; Crane, B.; Douchin, F.; Doumayrou, E.; Dubois, J. P.; Engel, C.; Etcheto, P.; Evrard, J.; Gelot, P.; Gomes, A.; Grabarnik, S.; Griffin, M.; Hargrave, P.; Jonathan, A.; Laureijs, R.; Laurens, A.; Lepennec, Y.; Leriche, B.; Longval, Y.; Martignac, J.; Marty, C.; Marty, W.; Maestre, S.; Masi, S.; Mirc, F.; Montel, J.; Motier, L.; Mot, B.; Narbonne, J.; Nicot, J. M.; Otrio, G.; Pajot, F.; Perot, E.; Pisano, G.; Ponthieu, N.; Ristorcelli, I.; Rodriquez, L.; Roudil, G.; Saccoccio, M.; Salatino, M.; Savini, G.; Simonella, O.; Tauber, J.; Tapie, P.; Tucker, C.; Versepuech, G.

    2015-09-01

    The Polarized Instrument for Long-wavelength Observation of the Tenuous interstellar medium (PILOT) is a balloon-borne astronomy experiment designed to study the linear polarization of the Far Infra-Red emission, 240 ~im (1.2 THz) and 550 ~tm (545 GHz) with an angular resolution of a few minutes of arc, from dust grains present in the diffuse interstellar medium, in our Galaxy and nearby galaxies. The polarisation of light is measured using a half-wave plate (HWP). We performed the instrumental tests from 2012 to 2014 and are planning a first scientific flight in September 2015 from Timmins, Ontario, Canada. This paper describes the measurement principles of PILOT, the results of the laboratory tests and its sky coverage. These include defocus tests, transmission measurements using a Fourier Transform Spectrometer at various positions of the HWP, and identification of internal straylight.

  11. A comparative study of red and blue light-emitting diodes and low-level laser in regeneration of the transected sciatic nerve after an end to end neurorrhaphy in rabbits.

    PubMed

    Takhtfooladi, Mohammad Ashrafzadeh; Sharifi, Davood

    2015-12-01

    This study aimed at evaluating the effects of red and blue light-emitting diodes (LED) and low-level laser (LLL) on the regeneration of the transected sciatic nerve after an end-to-end neurorrhaphy in rabbits. Forty healthy mature male New Zealand rabbits were randomly assigned into four experimental groups: control, LLL (680 nm), red LED (650 nm), and blue LED (450 nm). All animals underwent the right sciatic nerve neurotmesis injury under general anesthesia and end-to-end anastomosis. The phototherapy was initiated on the first postoperative day and lasted for 14 consecutive days at the same time of the day. On the 30th day post-surgery, the animals whose sciatic nerves were harvested for histopathological analysis were euthanized. The nerves were analyzed and quantified the following findings: Schwann cells, large myelinic axons, and neurons. In the LLL group, as compared to other groups, an increase in the number of all analyzed aspects was observed with significance level (P < 0.05). This finding suggests that postoperative LLL irradiation was able to accelerate and potentialize the peripheral nerve regeneration process in rabbits within 14 days of irradiation. PMID:26415928

  12. Generic inference of inflation models by non-Gaussianity and primordial power spectrum reconstruction

    SciTech Connect

    Dorn, Sebastian; Enßlin, Torsten A.; Ramirez, Erandy; Kunze, Kerstin E.

    2014-06-01

    We present a generic inference method for inflation models from observational data by the usage of higher-order statistics of the curvature perturbation on uniform density hypersurfaces. This method is based on the calculation of the posterior for the primordial non-Gaussianity parameters f{sub NL} and g{sub NL}, which in general depend on specific parameters of inflation and reheating models, and enables to discriminate among the still viable inflation models. To keep analyticity as far as possible to dispense with numerically expensive sampling techniques a saddle-point approximation is introduced, whose precision is validated for a numerical toy example. The mathematical formulation is done in a generic way so that the approach remains applicable to cosmic microwave background data as well as to large scale structure data. Additionally, we review a few currently interesting inflation models and present numerical toy examples thereof in two and three dimensions to demonstrate the efficiency of the higher-order statistics method. A second quantity of interest is the primordial power spectrum. Here, we present two Bayesian methods to infer it from observational data, the so called critical filter and an extension thereof with smoothness prior, both allowing for a non-parametric spectrum reconstruction. These methods are able to reconstruct the spectra of the observed perturbations and the primordial ones of curvature perturbation even in case of non-Gaussianity and partial sky coverage. We argue that observables like T- and B-modes permit to measure both spectra. This also allows to infer the level of non-Gaussianity generated since inflation.

  13. Performance of fluorescence retrieval methods and fluorescence spectrum reconstruction under various sensor spectral configurations

    NASA Astrophysics Data System (ADS)

    Li, Rong; Zhao, Feng

    2015-10-01

    Solar-induced chlorophyll fluorescence is closely related to photosynthesis and can serve as an indicator of plant status. Several methods have been proposed to retrieve fluorescence signal (Fs) either at specific spectral bands or within the whole fluorescence emission region. In this study, we investigated the precision of the fluorescence signal obtained through these methods under various sensor spectral characteristics. Simulated datasets generated by the SCOPE (Soil Canopy Observation, Photochemistry and Energy fluxes) model with known `true' Fs as well as an experimental dataset are exploited to investigate four commonly used Fs retrieval methods, namely the original Fraunhofer Line Discriminator method (FLD), the 3 bands FLD (3FLD), the improved FLD (iFLD), and the Spectral Fitting Methods (SFMs). Fluorescence Spectrum Reconstruction (FSR) method is also investigated using simulated datasets. The sensor characteristics of spectral resolution (SR) and signal-to-noise ratio (SNR) are taken into account. According to the results, finer SR and SNR both lead to better accuracy. Lowest precision is obtained for the FLD method with strong overestimation. Some improvements are made by the 3FLD method, but it still tends to overestimate. Generally, the iFLD method and the SFMs provide better accuracy. As to FSR, the shape and magnitude of reconstructed Fs are generally consistent with the `true' Fs distributions when fine SR is exploited. With coarser SR, however, though R2 of the retrieved Fs may be high, large bias is likely to be obtained as well.

  14. Reconstruction of the Primary Energy Spectrum from Fluorescence Telescope Data of the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Geenen, H.

    2007-07-01

    The Pierre Auger Observatory is the largest extensive air-shower (EAS) experiment in operation. It is still being constructed, and the final configuration will have detectors at the two sites Argentina and USA observing both celestial hemispheres. The aim of the experiment is to determine the energy, composition and origin of ultra-high energy cosmic-rays (UHECR) using two complementary detection techniques. The detector at the southern site presently contains more than 1400 (Jul. 2007) water-Cherenkov detectors at ground level (870 gcm^-2). Completion of the 3000 km^2 large detector array is expected by the end of 2007 with finally more than 1600 tanks. The atmosphere above the site is observed by 24 fluorescence telescopes located in four buildings at the boundary of the array. During clear moon-less nights, this configuration permits hybrid measurement of both longitudinal development of an EAS and lateral particle density at ground. All fluorescence telescopes are fully operational since February 2007. The aim of this work is to reconstruct the cosmic ray energy spectrum between a few 10^17 eV up to 10^20 eV. This would provide an overlap to spectral results from other experiments at lower energies. The hybrid detection provides an accurate geometry determination and thereby a good energy resolution. However, the energy threshold is limited to the threshold of the surface array: larger than a few 10^18 eV. The advantage of FD-monocular events (FD-mono) is a lower energy threshold in the aimed 10^17 eV regime. In addition, the present FD-mono exposure is about 1.5 times larger than the hybrid one. However, the energy resolution of FD-mono events is worse compared to hybrid, and the detector acceptance is strongly energy dependent. Therefore, the determination of the energy spectrum requires an unfolding procedure, which considers both the limited acceptance and the limited resolution. In this analysis the FD-mono data are reconstructed. The reconstruction

  15. Efficacy and safety of a NiTi CAR 27 compression ring for end-to-end anastomosis compared with conventional staplers: A real-world analysis in Chinese colorectal cancer patients

    PubMed Central

    Lu, Zhenhai; Peng, Jianhong; Li, Cong; Wang, Fulong; Jiang, Wu; Fan, Wenhua; Lin, Junzhong; Wu, Xiaojun; Wan, Desen; Pan, Zhizhong

    2016-01-01

    OBJECTIVES: This study aimed to evaluate the safety and efficacy of a new nickel-titanium shape memory alloy compression anastomosis ring, NiTi CAR 27, in constructing an anastomosis for colorectal cancer resection compared with conventional staples. METHODS: In total, 234 consecutive patients diagnosed with colorectal cancer receiving sigmoidectomy and anterior resection for end-to-end anastomosis from May 2010 to June 2012 were retrospectively analyzed. The postoperative clinical parameters, postoperative complications and 3-year overall survival in 77 patients using a NiTi CAR 27 compression ring (CAR group) and 157 patients with conventional circular staplers (STA group) were compared. RESULTS: There were no statistically significant differences between the patients in the two groups in terms of general demographics and tumor features. A clinically apparent anastomotic leak occurred in 2 patients (2.6%) in the CAR group and in 5 patients (3.2%) in the STA group (p=0.804). These eight patients received a temporary diverting ileostomy. One patient (1.3%) in the CAR group was diagnosed with anastomotic stricture through an electronic colonoscopy after 3 months postoperatively. The incidence of postoperative intestinal obstruction was comparable between the two groups (p=0.192). With a median follow-up duration of 39.6 months, the 3-year overall survival rate was 83.1% in the CAR group and 89.0% in the STA group (p=0.152). CONCLUSIONS: NiTi CAR 27 is safe and effective for colorectal end-to-end anastomosis. Its use is equivalent to that of the conventional circular staplers. This study suggests that NiTi CAR 27 may be a beneficial alternative in colorectal anastomosis in Chinese colorectal cancer patients. PMID:27276395

  16. Primary Energy Spectrum as Reconstructed from S(500) Measurements by KASCADE-Grande

    NASA Astrophysics Data System (ADS)

    Toma, G.; Apel, W. D.; Arteaga, J. C.; Badea, F.; Bekk, K.; Bertaina, M.; Blümer, J.; Bozdog, H.; Brancus, I. M.; Brüggemann, M.; Buchholz, P.; Cantoni, E.; Chiavassa, A.; Cossavella, F.; Daumiller, K.; de Souza, V.; Di Pierro, F.; Doll, P.; Engel, R.; Engler, J.; Finger, M.; Fuhrmann, D.; Ghia, P. L.; Gils, H. J.; Glasstetter, R.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel, J. R.; Huege, T.; Isar, P. G.; Kampert, K.-H.; Kang, D.; Kickelbick, D.; Klages, H. O.; Łuczak, P.; Mathes, H. J.; Mayer, H. J.; Milke, J.; Mitrica, B.; Morello, C.; Navarra, G.; Nehls, S.; Oehlschläger, J.; Ostapchenko, S.; Over, S.; Petcu, M.; Pierog, T.; Rebel, H.; Roth, M.; Schieler, H.; Schröder, F.; Sima, O.; Stümpert, M.; Trinchero, G. C.; Ulrich, H.; Weindl, A.; Wochele, J.; Wommer, M.; Zabierowski, J.

    2010-01-01

    In cosmic ray investigations by observations of extensive air showers (EAS) the general question arises how to relate the registered EAS observables to the energy of the primary particle from the cosmos entering into the atmosphere. We present results on the reconstruction of the primary energy spectrum of cosmic rays from the experimentally recorded S(500) observable using the KASCADE-Grande detector array. The KASCADE-Grande experiment is installed in Forschungszentrum Karlsruhe, Germany, and driven by an international collaboration. Previous EAS investigations have shown that for a fixed energy the charged particle density becomes independent of the primary mass at certain distances from the shower core. This feature can be used as an estimator for the primary energy. The particular radial distance from the shower core where this effect shows up is a characteristic of the detector. For the KASCADE-Grande experiment it was shown to be around 500 m, hence a notation S(500). Extensive simulation studies have shown that S(500) is mapping the primary energy. The constant intensity cut (CIC) method is applied to evaluate the attenuation of the S(500) observable with the zenith angle. An attenuation correction is applied and all recorded S(500) values are corrected for attenuation. A calibration of S(500) values with the primary energy has been worked out by simulations and was used for conversion providing the possibility to obtain the primary energy spectrum (in the energy range accessible to KASCADE-Grande 1010-1018 eV). The systematic uncertainties induced by different factors are considered.

  17. Experimental demonstration of a record high 11.25Gb/s real-time optical OFDM transceiver supporting 25km SMF end-to-end transmission in simple IMDD systems.

    PubMed

    Giddings, R P; Jin, X Q; Hugues-Salas, E; Giacoumidis, E; Wei, J L; Tang, J M

    2010-03-15

    The fastest ever 11.25Gb/s real-time FPGA-based optical orthogonal frequency division multiplexing (OOFDM) transceivers utilizing 64-QAM encoding/decoding and significantly improved variable power loading are experimentally demonstrated, for the first time, incorporating advanced functionalities of on-line performance monitoring, live system parameter optimization and channel estimation. Real-time end-to-end transmission of an 11.25Gb/s 64-QAM-encoded OOFDM signal with a high electrical spectral efficiency of 5.625bit/s/Hz over 25km of standard and MetroCor single-mode fibres is successfully achieved with respective power penalties of 0.3dB and -0.2dB at a BER of 1.0 x 10(-3) in a directly modulated DFB laser-based intensity modulation and direct detection system without in-line optical amplification and chromatic dispersion compensation. The impacts of variable power loading as well as electrical and optical components on the transmission performance of the demonstrated transceivers are experimentally explored in detail. In addition, numerical simulations also show that variable power loading is an extremely effective means of escalating system performance to its maximum potential. PMID:20389570

  18. Reconstruction of the primordial fluctuation spectrum from the five-year WMAP data by the cosmic inversion method with band-power decorrelation analysis

    SciTech Connect

    Nagata, Ryo; Yokoyama, Jun'ichi

    2008-12-15

    The primordial curvature fluctuation spectrum is reconstructed by the cosmic inversion method using the five-year Wilkinson Microwave Anisotropy Probe data of the cosmic microwave background temperature anisotropy. We apply the covariance matrix analysis and decompose the reconstructed spectrum into statistically independent band-powers. The statistically significant deviation from a simple power-law spectrum suggested by the analysis of the first-year data is not found in the five-year data except possibly at one point near the border of the wave number domain where accurate reconstruction is possible.

  19. Experimental demonstrations of record high REAM intensity modulator-enabled 19.25Gb/s real-time end-to-end dual-band optical OFDM colorless transmissions over 25km SSMF IMDD systems.

    PubMed

    Zhang, Q W; Hugues-Salas, E; Giddings, R P; Wang, M; Tang, J M

    2013-04-01

    Record-high 19.25Gb/s real-time end-to-end dual-band optical OFDM (OOFDM) colorless transmissions across the entire C-band are experimentally demonstrated, for the first time, in reflective electro-absorption modulator (REAM)-based 25km standard SMF systems using intensity modulation and direct detection. Adaptively modulated baseband (0-2GHz) and passband (6.125 ± 2GHz) OFDM RF sub-bands, supporting signal line rates of 9.75Gb/s and 9.5Gb/s respectively, are independently generated and detected with FPGA-based DSP clocked at only 100MHz as well as DACs/ADCs operating at sampling speeds as low as 4GS/s. The two OFDM sub-bands are electrically multiplexed for intensity modulation of a single optical carrier by an 8GHz REAM. The REAM colorlessness is experimentally characterized, based on which optimum REAM operating conditions are identified. To maximize and balance the signal transmission performance of each sub-band, on-line adaptive transceiver optimization functions and live performance monitoring are fully exploited to optimize key OOFDM transceiver and system parameters. For different wavelengths within the C-band, corresponding minimum received optical powers at the FEC limit vary in a range of <0.5dB and bit error rate performances for both baseband and passband signals are almost identical. Furthermore, detailed investigations are also undertaken of the maximum aggregated signal line rate sensitivity to electrical sub-band power variation. It is shown that the aforementioned system has approximately 3dB tolerance to RF sub-band power variation. PMID:23572005

  20. Reconstruction of a 6-MeV bremsstrahlung spectrum by multi-layer absorption based on LiF:Mg, Cu, P

    NASA Astrophysics Data System (ADS)

    Huang, Jian-Wei; Wang, Nai-Yan

    2014-10-01

    In this paper, TLD (LiF: Mg, Cu, P) is used as detector. A multi-layer absorption (MLA) model is designed. Combined with Monte-Carlo processes, a bremsstrahlung X-ray spectrum is reconstructed by an iterative method; the reconstructed results agree with the results of simulations by the MCNP process essentially, especially in middle energy region.

  1. An accurate method for energy spectrum reconstruction of Linac beams based on EPID measurements of scatter radiation

    NASA Astrophysics Data System (ADS)

    Juste, B.; Miró, R.; Verdú, G.; Santos, A.

    2014-06-01

    This work presents a methodology to reconstruct a Linac high energy photon spectrum beam. The method is based on EPID scatter images generated when the incident photon beam impinges onto a plastic block. The distribution of scatter radiation produced by this scattering object placed on the external EPID surface and centered at the beam field size was measured. The scatter distribution was also simulated for a series of monoenergetic identical geometry photon beams. Monte Carlo simulations were used to predict the scattered photons for monoenergetic photon beams at 92 different locations, with 0.5 cm increments and at 8.5 cm from the centre of the scattering material. Measurements were performed with the same geometry using a 6 MeV photon beam produced by the linear accelerator. A system of linear equations was generated to combine the polyenergetic EPID measurements with the monoenergetic simulation results. Regularization techniques were applied to solve the system for the incident photon spectrum. A linear matrix system, A×S=E, was developed to describe the scattering interactions and their relationship to the primary spectrum (S). A is the monoenergetic scatter matrix determined from the Monte Carlo simulations, S is the incident photon spectrum, and E represents the scatter distribution characterized by EPID measurement. Direct matrix inversion methods produce results that are not physically consistent due to errors inherent in the system, therefore Tikhonov regularization methods were applied to address the effects of these errors and to solve the system for obtaining a consistent bremsstrahlung spectrum.

  2. Study and Implementation of the End-to-End Data Pipeline for the Virtis Imaging Spectrometer Onbaord Venus Express: "From Science Operations Planning to Data Archiving and Higher Lever Processing"

    NASA Astrophysics Data System (ADS)

    Cardesín Moinelo, Alejandro

    2010-04-01

    This PhD Thesis describes the activities performed during the Research Program undertaken for two years at the Istituto Nazionale di AstroFisica in Rome, Italy, as active member of the VIRTIS Technical and Scientific Team, and one additional year at the European Space Astronomy Center in Madrid, Spain, as member of the Mars Express Science Ground Segment. This document will show a study of all sections of the Science Ground Segment of the Venus Express mission, from the planning of the scientific operations, to the generation, calibration and archiving of the science data, including the production of valuable high level products. We will present and discuss here the end-to-end diagram of the ground segment from the technical and scientific point of view, in order to describe the overall flow of information: from the original scientific requests of the principal investigator and interdisciplinary teams, up to the spacecraft, and down again for the analysis of the measurements and interpretation of the scientific results. These scientific results drive to new and more elaborated scientific requests, which are used as feedback to the planning cycle, closing the circle. Special attention is given here to describe the implementation and development of the data pipeline for the VIRTIS instrument onboard Venus Express. During the research program, both the raw data generation pipeline and the data calibration pipeline were developed and automated in order to produce the final raw and calibrated data products from the input telemetry of the instrument. The final raw and calibrated products presented in this work are currently being used by the VIRTIS Science team for data analysis and are distributed to the whole scientific community via the Planetary Science Archive. More than 20,000 raw data files and 10,000 calibrated products have already been generated after almost 4 years of mission. In the final part of the Thesis, we will also present some high level data

  3. TOWARD END-TO-END MODELING FOR NUCLEAR EXPLOSION MONITORING: SIMULATION OF UNDERGROUND NUCLEAR EXPLOSIONS AND EARTHQUAKES USING HYDRODYNAMIC AND ANELASTIC SIMULATIONS, HIGH-PERFORMANCE COMPUTING AND THREE-DIMENSIONAL EARTH MODELS

    SciTech Connect

    Rodgers, A; Vorobiev, O; Petersson, A; Sjogreen, B

    2009-07-06

    This paper describes new research being performed to improve understanding of seismic waves generated by underground nuclear explosions (UNE) by using full waveform simulation, high-performance computing and three-dimensional (3D) earth models. The goal of this effort is to develop an end-to-end modeling capability to cover the range of wave propagation required for nuclear explosion monitoring (NEM) from the buried nuclear device to the seismic sensor. The goal of this work is to improve understanding of the physical basis and prediction capabilities of seismic observables for NEM including source and path-propagation effects. We are pursuing research along three main thrusts. Firstly, we are modeling the non-linear hydrodynamic response of geologic materials to underground explosions in order to better understand how source emplacement conditions impact the seismic waves that emerge from the source region and are ultimately observed hundreds or thousands of kilometers away. Empirical evidence shows that the amplitudes and frequency content of seismic waves at all distances are strongly impacted by the physical properties of the source region (e.g. density, strength, porosity). To model the near-source shock-wave motions of an UNE, we use GEODYN, an Eulerian Godunov (finite volume) code incorporating thermodynamically consistent non-linear constitutive relations, including cavity formation, yielding, porous compaction, tensile failure, bulking and damage. In order to propagate motions to seismic distances we are developing a one-way coupling method to pass motions to WPP (a Cartesian anelastic finite difference code). Preliminary investigations of UNE's in canonical materials (granite, tuff and alluvium) confirm that emplacement conditions have a strong effect on seismic amplitudes and the generation of shear waves. Specifically, we find that motions from an explosion in high-strength, low-porosity granite have high compressional wave amplitudes and weak shear

  4. The Dosimetric Importance of Six Degree of Freedom Couch End to End Quality Assurance for SRS/SBRT Treatments when Comparing Intensity Modulated Radiation Therapy to Volumetric Modulated Arc Therapy

    NASA Astrophysics Data System (ADS)

    Ulizio, Vincent Michael

    With the advancement of technology there is an increasing ability for lesions to be treated with higher radiation doses each fraction. This also allows for low fractionated treatments. Because the patient is receiving a higher dose of radiation per fraction and because of the fast dose falloff in these targets there must be extreme accuracy in the delivery. The 6 DOF couch allows for extra rotational corrections and for a more accurate set-up. The movement of the couch needs to be verified to be accurate and because of this, end to end quality assurance tests for the couch have been made. After the set-up is known to be accurate then different treatment techniques can be studied. SBRT of the Spine has a very fast dose falloff near the spinal cord and was typically treated with IMRT. Treatment plans generated using this technique tend to have streaks of low dose radiation, so VMAT is being studied to determine if this treatment technique can reduce the low dose radiation volume as well as improve OAR sparing. For the 6 DOF couch QA, graph paper is placed on the anterior and right lateral sides of the VisionRT OSMS Cube Phantom. Each rotational shift is then applied individually, with a 3 degree shift in the positive and negative directions for pitch and roll. A mark is drawn on the paper to record each shift. A CBCT is then taken of the Cube and known shifts are applied and then an additional CBCT is taken to return the Cube to isocenter. The original IMRT plans for SBRT of the Spine are evaluated and then a plan is made utilizing VMAT. These plans are then compared for low dose radiation, OAR sparing, and conformity. If the original IMRT plan is determined to be an inferior treatment to what is acceptable, then this will be re-planned and compared to the VMAT plan. The 6 DOF couch QA tests have proven to be accurate and reproducible. The average deviations in the 3 degree and -3 degree pitch and roll directions were 0.197, 0.068, 0.091, and 0.110 degrees

  5. Reconstructing the primordial spectrum of fluctuations of the universe from the observed nonlinear clustering of galaxies

    NASA Technical Reports Server (NTRS)

    Hamilton, A. J. S.; Matthews, Alex; Kumar, P.; Lu, Edward

    1991-01-01

    It was discovered that the nonlinear evolution of the two point correlation function in N-body experiments of galaxy clustering with Omega = 1 appears to be described to good approximation by a simple general formula. The underlying form of the formula is physically motivated, but its detailed representation is obtained empirically by fitting to N-body experiments. In this paper, the formula is presented along with an inverse formula which converts a final, nonlinear correlation function into the initial linear correlation function. The inverse formula is applied to observational data from the CfA, IRAs, and APM galaxy surveys, and the initial spectrum of fluctuations of the universe, if Omega = 1.

  6. Reconstruction of the energy spectrum of electrons accelerated in the April 15, 2002 solar flare based on IRIS X-ray spectrometer measurements

    NASA Astrophysics Data System (ADS)

    Motorina, G. G.; Kudryavtsev, I. V.; Lazutkov, V. P.; Savchenko, M. I.; Skorodumov, D. V.; Charikov, Yu. E.

    2016-04-01

    We reconstruct the energy distribution of electrons accelerated in the April 15, 2002 solar flare on the basis of the data from the IRIS X-ray spectrometer onboard the CORONAS-F satellite. We obtain the solution to the integral equations describing the transformation of the spectrum of X-ray photons during the recording and reconstruction of the spectrum of accelerated electrons in the bremsstrahlung source using the random search method and the Tikhonov regularization method. In this event, we detected a singularity in the electron spectrum associated with the existence of a local minimum in the energy range 40-60 keV, which cannot be detected by a direct method.

  7. [RECONSTRUCTIVE-RESTORATION OPERATIONS AFTER OBSTRUCTIVE RESECTION OF LARGE BOWEL].

    PubMed

    Yerko, I P; Balabushko, S B

    2016-01-01

    The results of reconstructive-restoration operations, performed after obstructive resection of large bowel for colorectal cancer, were analyzed. The postoperative complications rate have constituted 11.7%. The most frequent cause of morbidity, 3.9%, was partial insufficiency of sutures of interintestinal anastomosis, formatted in the end to end fashion. Lethality have constituted 1.1%. PMID:27249921

  8. Tracheal reconstructions.

    PubMed

    Srikrishna, S V; Shekar, P S; Shetty, N

    1998-12-01

    Surgical reconstruction of the trachea is a relatively complex procedure. We had 20 cases of tracheal stenosis. We have a modest experience of 16 tracheal reconstructions for acquired tracheal stenosis. Two patients underwent laser treatment while another two died before any intervention. The majority of these cases were a result of prolonged ventilation (14 cases), following organophosphorous poisoning (11 cases), Guillain-Barré syndrome, bullet injury, fat embolism and surprisingly only one tumor, a case of mucoepidermoid carcinoma, who had a very unusual presentation. There were 12 males and 4 females in this series, age ranging from 12-35 years. The duration of ventilation ranged from 1-21 days and the interval from decannulation to development of stridor was between 5-34 days. Six of them were approached by the cervical route, 5 by thoracotomy and cervical approach, 2 via median sternotomy and 3 by thoracotomy alone. Five of them required an additional laryngeal drop and 1 required pericardiotomy and release of pulmonary veins to gain additional length. The excised segments of trachea measured 3 to 5 cms in length. All were end to end anastomosis with interrupted Vicryl sutures. We have had no experience with stents or prosthetic tubes. Three patients developed anastomotic leaks which were controlled conservatively. Almost all of them required postoperative tracheo-bronchial suctioning with fibreoptic bronchoscope. We had one death in this series due to sepsis. PMID:9914459

  9. Pancreatectomy with vein reconstruction: technique matters

    PubMed Central

    Dua, Monica M; Tran, Thuy B; Klausner, Jill; Hwa, Kim J; Poultsides, George A; Norton, Jeffrey A; Visser, Brendan C

    2015-01-01

    Background A variety of techniques have been described for portal vein (PV) and/or superior mesenteric vein (SMV) resection/reconstruction during a pancreatectomy. The ideal strategy remains unclear. Methods Patients who underwent PV/SMV resection/reconstruction during a pancreatectomy from 2005 to 2014 were identified. Medical records and imaging were retrospectively reviewed for operative details and outcomes, with particular emphasis on patency. Results Ninety patients underwent vein resection/reconstruction with one of five techniques: (i) longitudinal venorrhaphy (LV, n = 17); (ii) transverse venorrhaphy (TV, n = 9); (iii) primary end-to-end (n = 28); (iv) patch venoplasty (PV, n = 17); and (v) interposition graft (IG, n = 19). With a median follow-up of 316 days, thrombosis was observed in 16/90 (18%). The rate of thrombosis varied according to technique. All patients with primary end-to-end or TV remained patent. LV, PV and IG were all associated with significant rates of thrombosis (P = 0.001 versus no thrombosis). Comparing thrombosed to patent, there were no differences with respect to pancreatectomy type, pre-operative knowledge of vein involvement and neoadjuvant therapy. Prophylactic aspirin was used in 69% of the total cohort (66% of patent, 81% of thrombosed) and showed no protective benefit. Conclusions Primary end-to-end and TV have superior patency than the alternatives after PV/SMV resection and should be the preferred techniques for short (<3 cm) reconstructions. PMID:26223388

  10. End-to-End Performance Management for Large Distributed Storage

    SciTech Connect

    Almadena Chtchelkanova

    2012-03-18

    Storage systems for large distributed clusters of computer servers are themselves large and distributed. Their complexity and scale make it hard to ensure that applications using them get good, predictable performance. At the same time, shared access to the system from multiple applications, users, and internal system activities leads to a need for predictable performance. This research investigates mechanisms for improving storage system performance in large distributed storage systems through mechanisms that integrate the performance aspects of the path that I/O operations take through the system, from the application interface on the compute server, through the network, to the storate servers. The research focuses on five parts of the I/O path in a distributed storage system: I/O scheduling at the storage server, storage server cache management, client-to-server network flow control, client-to-server connection management, and client cache management.

  11. End-to-end experiment management in HPC

    SciTech Connect

    Bent, John M; Kroiss, Ryan R; Torrez, Alfred; Wingate, Meghan

    2010-01-01

    Experiment management in any domain is challenging. There is a perpetual feedback loop cycling through planning, execution, measurement, and analysis. The lifetime of a particular experiment can be limited to a single cycle although many require myriad more cycles before definite results can be obtained. Within each cycle, a large number of subexperiments may be executed in order to measure the effects of one or more independent variables. Experiment management in high performance computing (HPC) follows this general pattern but also has three unique characteristics. One, computational science applications running on large supercomputers must deal with frequent platform failures which can interrupt, perturb, or terminate running experiments. Two, these applications typically integrate in parallel using MPI as their communication medium. Three, there is typically a scheduling system (e.g. Condor, Moab, SGE, etc.) acting as a gate-keeper for the HPC resources. In this paper, we introduce LANL Experiment Management (LEM), an experimental management framework simplifying all four phases of experiment management. LEM simplifies experiment planning by allowing the user to describe their experimental goals without having to fully construct the individual parameters for each task. To simplify execution, LEM dispatches the subexperiments itself thereby freeing the user from remembering the often arcane methods for interacting with the various scheduling systems. LEM provides transducers for experiments that automatically measure and record important information about each subexperiment; these transducers can easily be extended to collect additional measurements specific to each experiment. Finally, experiment analysis is simplified by providing a general database visualization framework that allows users to quickly and easily interact with their measured data.

  12. Nursing studies laid end to end form a circle.

    PubMed

    Friss, L

    1994-01-01

    As early as 1915, leaders in the nursing profession were concerned with the "image problem of nurses," which they saw as needing improvement. Since then, countless studies, reports, and commissions have attempted to explain and solve perceived shortages of registered nurses, which have occurred regularly after brief periods of quiescence or oversupply. Usually, their recommendations have hinged on nurses changing their image. In fact, few of these studies have dealt with the real issues of nursing work, which are a narrow pay range, little extra pay for working on undesirable shifts, disincentives for full-time work, pay unrelated to education, and education unconnected to job level. The multiple studies and commissions do nothing more than recycle data and in the process obscure fundamental problems. Educational funding has been no more successful. Their ineffectiveness suggests the need for less "image enhancement" and more support from physicians and employers to bring about systemic reform. This includes licensing nurses according to their education, assigning them according to their competencies and education, and paying accordingly. These measures, and only these, will eventually curtail the cycles of nursing "shortages." PMID:7844324

  13. Kepler Mission: End-to-End System Demonstration

    NASA Technical Reports Server (NTRS)

    Borucki, William; Koch, D.; Dunham, E.; Jenkins, J.; Witteborn, F.; Updike, T.; DeVincenzi, Donald L. (Technical Monitor)

    2000-01-01

    A test facility has been constructed to demonstrate the capability of differential ensemble photometry to detect transits of Earth-size planets orbiting solar-like stars. The main objective is to determine the effects of various noise sources on the capability of a CCD photometer to maintain a system relative precision of 1 x $10^(-5)$ for mv = 12 stars in the presence of system-induced noise sources. The facility includes a simulated star field, fast optics to simulate the telescope, a thinned back-illuminated CCD similar to those to be used on the spacecraft and computers to perform the onboard control, data processing and extraction. The test structure is thermally and mechanically isolated so that each source of noise can be introduced in a controlled fashion and evaluated for its contribution to the total noise budget. The effects of pointing errors or a changing thermal environment are imposed by piezo-electric devices. Transits are injected by heating small wires crossing apertures in the star plate. Signals as small as those from terrestrial-size transits of solar-like stars are introduced to demonstrate that such planets can be detected under realistic noise conditions. Examples of imposing several noise sources and the resulting detectabilities are presented. These show that a differential ensemble photometric approach CCD photometer can readily detect signals associated with Earth-size transits.

  14. On Estimating End-to-End Network Path Properties

    NASA Technical Reports Server (NTRS)

    Allman, Mark; Paxson, Vern

    1999-01-01

    The more information about current network conditions available to a transport protocol, the more efficiently it can use the network to transfer its data. In networks such as the Internet, the transport protocol must often form its own estimates of network properties based on measurements per-formed by the connection endpoints. We consider two basic transport estimation problems: determining the setting of the retransmission timer (RTO) for are reliable protocol, and estimating the bandwidth available to a connection as it begins. We look at both of these problems in the context of TCP, using a large TCP measurement set [Pax97b] for trace-driven simulations. For RTO estimation, we evaluate a number of different algorithms, finding that the performance of the estimators is dominated by their minimum values, and to a lesser extent, the timer granularity, while being virtually unaffected by how often round-trip time measurements are made or the settings of the parameters in the exponentially-weighted moving average estimators commonly used. For bandwidth estimation, we explore techniques previously sketched in the literature [Hoe96, AD98] and find that in practice they perform less well than anticipated. We then develop a receiver-side algorithm that performs significantly better.

  15. Proposal of an end-to-end emergency medical system.

    PubMed

    El-Masri, Samir; Saddik, Basema

    2011-01-01

    A new comprehensive emergency system has been proposed to facilitate and computerize all the processes involved in an emergency from the initial contact to the ambulance emergency system, to finding the right and nearest available ambulance, and through to accessing a Smart Online Electronic Health Record (SOEHR). The proposed system will critically assist in pre-hospital treatments, indentify availability of the nearest available specialized hospital and communicate with the Hospital Emergency Department System (HEDS) to provide early information about the incoming patient for preparation to receive and assist. PMID:21893771

  16. Going End to End to Deliver High-Speed Data

    NASA Technical Reports Server (NTRS)

    2005-01-01

    By the end of the 1990s, the optical fiber "backbone" of the telecommunication and data-communication networks had evolved from megabits-per-second transmission rates to gigabits-per-second transmission rates. Despite this boom in bandwidth, however, users at the end nodes were still not being reached on a consistent basis. (An end node is any device that does not behave like a router or a managed hub or switch. Examples of end node objects are computers, printers, serial interface processor phones, and unmanaged hubs and switches.) The primary reason that prevents bandwidth from reaching the end nodes is the complex local network topology that exists between the optical backbone and the end nodes. This complex network topology consists of several layers of routing and switch equipment which introduce potential congestion points and network latency. By breaking down the complex network topology, a true optical connection can be achieved. Access Optical Networks, Inc., is making this connection a reality with guidance from NASA s nondestructive evaluation experts.

  17. Scalable end-to-end ATM encryption test results

    SciTech Connect

    Pierson, L.G.

    1995-10-01

    Customers of Asynchronous Transfer Mode (ATM) services may need a variety of data authenticity and privacy assurances. Cryptographic methods can be used to assure authenticity and privacy, but are hard to scale for implementation at high speed. The incorporation of these methods into computer networks can severely impact functionality, reliability, and performance. To study these trade-offs, a prototype encryptor/decryptor was developed. This effort demonstrated the viability of implementing certain encryption techniques in high speed networks. The research prototype processes ATM cells in a SONET OC-3 payload. This paper describes the functionality, reliability, security, and performance design trade-offs investigated with the prototype.

  18. End-to-end modelling of He II flow systems

    NASA Technical Reports Server (NTRS)

    Mord, A. J.; Snyder, H. A.; Newell, D. A.

    1992-01-01

    A practical computer code has been developed which uses the accepted two-fluid model to simulate He II flow in complicated systems. The full set of equations are used, retaining the coupling between the pressure, temperature and velocity fields. This permits modeling He II flow over the full range of conditions, from strongly or weakly driven flow through large pipes, narrow channels and porous media. The system may include most of the components used in modern superfluid flow systems: non-ideal thermomechanical pumps, tapered sections, constrictions, lines with heated side walls and heat exchangers. The model is validated by comparison with published experimental data. It is applied to a complex system to show some of the non-intuitive feedback effects that can occur. This code is ready to be used as a design tool for practical applications of He II. It can also be used for the design of He II experiments and as a tool for comparison of experimental data with the standard two-fluid model.

  19. Image reconstruction

    SciTech Connect

    Defrise, Michel; Gullberg, Grant T.

    2006-04-05

    We give an overview of the role of Physics in Medicine andBiology in development of tomographic reconstruction algorithms. We focuson imaging modalities involving ionizing radiation, CT, PET and SPECT,and cover a wide spectrum of reconstruction problems, starting withclassical 2D tomogra tomography in the 1970s up to 4D and 5D problemsinvolving dynamic imaging of moving organs.

  20. SU-F-18C-02: Evaluations of the Noise Power Spectrum of a CT Iterative Reconstruction Technique for Radiation Therapy

    SciTech Connect

    Dolly, S; Chen, H; Anastasio, M; Mutic, S; Li, H

    2014-06-15

    Purpose: To quantitatively assess the noise power spectrum (NPS) of the new, commercially released CT iterative reconstruction technique, iDose{sup 4} from Philips, to compare it with filtered back-projection techniques (FBP), and to provide clinical practice suggestions for radiation therapy. Methods: A uniform phantom was CT imaged with 120kVp tube potential over a range of mAs (250-3333). The image sets were reconstructed using two reconstruction algorithms (FBP and iDose{sup 4} with noise reduction levels 1, 3, and 6) and three reconstruction filters (standard B, smooth A, and sharp C), after which NPS variations were analyzed and compared on region of interest (ROI) sizes (16×16 to 128×128 pixels), ROI radii (0–65 mm), reconstruction algorithms, reconstruction filters, and mAs. Results: The NPS magnitude and shape depended considerably on ROI size and location for both reconstruction algorithms. Regional noise variance became more stationary as ROI size decreased, minimizing NPS artifacts. The optimal 32×32-pixel ROI size balanced the trade-off between stationary noise and adequate sampling. NPS artifacts were greatest at the center of reconstruction space and decreased with increasing ROI distance from the center. The optimal ROI position was located near the phantom's radial midpoint (∼40mm). For sharper filters, the NPS magnitude and the maximum magnitude frequency increased. Higher dose scans yielded lower NPS magnitudes for both reconstruction algorithms and all filters. Compared to FBP, the iDose{sup 4} algorithm reduced the NPS magnitude while preferentially reducing noise at mid-range spatial frequencies, altering noise texture. This reduction was more significant with increasing iDose{sup 4} noise reduction level. Conclusion: Compared to pixel standard deviation, NPS has greater clinical potential for task-based image quality assessment, describing both the magnitude and spatial frequency characteristics of image noise. While iDose{sup 4

  1. Modeling the recorded spectrum and reconstructing the transfer function of the wideband ionospheric HF radio channel in the case of chirp sounding

    NASA Astrophysics Data System (ADS)

    Ilyin, N. V.; Davydenko, M. A.; Khakhinov, V. V.

    2007-05-01

    We model theoretically the received spectrum in the case of sounding of the ionospheric HF radio channel by a chirp signal. It is shown that the result of processing of an individual time sample of the received signal is equivalent to the sounding of the radio channel by a complex narrow-band pulsed signal such that the group delays of its propagation modes determine the maxima in the received spectrum. We analyze the quadrature components of realizations of the received signal at the intermediate frequency at the bandpass-filter output in the receiving channel of the chirp ionosonde. The results of our analysis show the possibility of reconstructing the transfer function of a HF radio channel in the sounding-frequency band for the delay range determined by the characteristics of the intermediate-frequency bandpass filter. We propose a method for reconstructing the transfer function of the ionospheric radio channel, which involves supplementing the circuit of primary processing of the signal by a corrective digital filter with specified amplitude-frequency and phase-frequency characteristics. The proposed method can be used for all operating regimes of the chirp ionosonde in the case of digital recording and processing of signals.

  2. The sun protection factor (SPF) inadequately defines broad spectrum photoprotection: demonstration using skin reconstructed in vitro exposed to UVA, UVBor UV-solar simulated radiation.

    PubMed

    Bernerd, Françoise; Vioux, Corinne; Lejeune, François; Asselineau, Daniel

    2003-01-01

    Wavelength specific biological damage has been previously identified in human skin reconstructed in vitro. Sunburn cell and pyrimidine dimers were found after UVB exposure, and alterations of dermal fibroblasts after UVA exposure. These damages permitted us to discriminate UVB and UVA single absorbers. The present study shows that these biological effects can be obtained simultaneously by a combined UVB + UVA exposure using ultraviolet solar simulated light (UV-SSR), which represents a relevant UV source. In addition, the protection afforded by two broad spectrum sunscreen complex formulations was assessed after topical application. These two formulations displayed the same sun protection factor but different UVA protection factors determined by the persistent pigment darkening (PPD) method. Dose response experiments of UVA or UV-SSR showed that the preparation with the highest PF-UVA provided a better protection with regard to dermal damage compared to the other formulation. Using an original UVB source to obtain the UVB portion of SSR spectrum, the preparations provided the same protection. This study strikingly illustrates the fact that the photoprotection afforded by two sunscreen formulations having similar SPF values is not equal with regard to dermal damage related to photoaging. PMID:12804982

  3. Thoracoscopic tracheal resection and reconstruction for adenoid cystic carcinoma.

    PubMed

    Jiao, Wenjie; Zhu, Dezhang; Cheng, Zhaozhong; Zhao, Yandong

    2015-01-01

    We describe a novel technique of thoracoscopic circumferential tracheal resection and end-to-end anastomosis. A 60-year-old woman presented with wheezing and progressive dyspnea. Computed tomography scan revealed a mass at the lower trachea, and a nitinol mesh stent was implanted by bronchoscopy. After 2 weeks, a complete thoracoscopic tracheal resection and reconstruction was performed. The postoperative course was uneventful. The final pathologic examination confirmed the diagnosis of primary adenoid cystic carcinoma of the trachea. PMID:25555982

  4. Spectrum reconstruction using relative-deviation-based kernel regression in temporally and spatially modulated Fourier transform imaging spectrometer.

    PubMed

    Huang, Fengzhen; Yuan, Yan; Li, Jingzhen; Cao, Jun

    2015-08-01

    During the temporally and spatially modulated Fourier transform imaging spectrometer push-broom scanning process, the motion state of the spectrometer platform can vary. Thus, the target interferogram obtained from the image sequence deviates from the ideal interferogram obtained using high platform stability. The recovered target spectrum will not reflect the true target characteristics. We adopted target tracking to acquire the target position in the image sequence via a proposed kernel regression, with a relative deviation method for determining the target intensities, and the recovery of the spectrogram using the nonuniform fast Fourier transform algorithm. We tested our algorithm on simulated and experimentally obtained aerial images and, from comparison with accurate spectrograms, demonstrate the effectiveness of the proposed method. PMID:26368088

  5. Cathodoluminescence Spectrum Imaging Software

    Energy Science and Technology Software Center (ESTSC)

    2011-04-07

    The software developed for spectrum imaging is applied to the analysis of the spectrum series generated by our cathodoluminescence instrumentation. This software provides advanced processing capabilities s such: reconstruction of photon intensity (resolved in energy) and photon energy maps, extraction of the spectrum from selected areas, quantitative imaging mode, pixel-to-pixel correlation spectrum line scans, ASCII, output, filling routines, drift correction, etc.

  6. Reconstruction of the radionuclide spectrum of liquid radioactive waste released into the Techa river in 1949-1951.

    PubMed

    Mokrov, Yuri G

    2003-04-01

    The major part of the liquid radioactive waste released by the Mayak Production Association (PA) radiochemical plant into the Techa river occurred in 1949-1951, but there is information on only one single radiochemical analysis of a water sample taken on 24 and 25 September 1951. These data are here used to assess the spectrum of radionuclides that were released between 1949 and 1951. For this purpose, details of the radiochemical methods of radionuclide extraction and radiometric measurements of beta-activity used at Mayak PA in the 1950s have been taken into account. It is concluded that the data from the radiochemical measurements agree with the theoretical composition of fission products in uranium after exposure times in the reactor (120 days) and subsequent hold times (35 days) that were typical for the procedures at that time. The results of the analysis are at variance with assumptions that underlie the current Techa river dosimetry system. They confirm the conclusion that the external doses to the Techa river residents in the critical period up to 1952 were predominantly due to short-lived fission products. PMID:12720000

  7. Restoration and reconstruction from overlapping images

    NASA Technical Reports Server (NTRS)

    Reichenbach, Stephen E.; Kaiser, Daniel J.; Hanson, Andrew L.; Li, Jing

    1997-01-01

    This paper describes a technique for restoring and reconstructing a scene from overlapping images. In situations where there are multiple, overlapping images of the same scene, it may be desirable to create a single image that most closely approximates the scene, based on all of the data in the available images. For example, successive swaths acquired by NASA's planned Moderate Imaging Spectrometer (MODIS) will overlap, particularly at wide scan angles, creating a severe visual artifact in the output image. Resampling the overlapping swaths to produce a more accurate image on a uniform grid requires restoration and reconstruction. The one-pass restoration and reconstruction technique developed in this paper yields mean-square-optimal resampling, based on a comprehensive end-to-end system model that accounts for image overlap, and subject to user-defined and data-availability constraints on the spatial support of the filter.

  8. Characterization and MCNP simulation of neutron energy spectrum shift after transmission through strong absorbing materials and its impact on tomography reconstructed image.

    PubMed

    Hachouf, N; Kharfi, F; Boucenna, A

    2012-10-01

    An ideal neutron radiograph, for quantification and 3D tomographic image reconstruction, should be a transmission image which exactly obeys to the exponential attenuation law of a monochromatic neutron beam. There are many reasons for which this assumption does not hold for high neutron absorbing materials. The main deviations from the ideal are due essentially to neutron beam hardening effect. The main challenges of this work are the characterization of neutron transmission through boron enriched steel materials and the observation of beam hardening. Then, in our work, the influence of beam hardening effect on neutron tomographic image, for samples based on these materials, is studied. MCNP and FBP simulation are performed to adjust linear attenuation coefficients data and to perform 2D tomographic image reconstruction with and without beam hardening corrections. A beam hardening correction procedure is developed and applied based on qualitative and quantitative analyses of the projections data. Results from original and corrected 2D reconstructed images obtained shows the efficiency of the proposed correction procedure. PMID:22871438

  9. Tracheal Reconstruction for Comlex Acute Tracheal Stenosis

    PubMed Central

    Fatimi, Saulat H.; Qasim Raza, M.; Ghani, Alina; Shah, Nilay; Ashfaq, Awais

    2013-01-01

    Tracheal stenosis refers to a reduction in the size of the tracheal lumen and can be due to a myriad of reasons, but the most common remains trauma. In iatrogenic situations, internal trauma is the most likely culprit, resulting from prolonged intubation. Our case reviews a patient who developed severe tracheal stenosis (90% reduction in lumen size) within a month of a threeday- long intubation, and presented to the emergency room with dyspnea, orthopnea, and stridor. Tracheal reconstruction with resection of the stenosed segment and end-to-end anastomosis was done. The patient returned a month later with re-stenosis, and underwent tracheal dilatation. Subsequently, he was discharged with a tracheostomy with no problems thereafter. PMID:25628886

  10. An end-to-end assessment of extreme weather impacts on food security

    NASA Astrophysics Data System (ADS)

    Chavez, Erik; Conway, Gordon; Ghil, Michael; Sadler, Marc

    2015-11-01

    Both governments and the private sector urgently require better estimates of the likely incidence of extreme weather events, their impacts on food crop production and the potential consequent social and economic losses. Current assessments of climate change impacts on agriculture mostly focus on average crop yield vulnerability to climate and adaptation scenarios. Also, although new-generation climate models have improved and there has been an exponential increase in available data, the uncertainties in their projections over years and decades, and at regional and local scale, have not decreased. We need to understand and quantify the non-stationary, annual and decadal climate impacts using simple and communicable risk metrics that will help public and private stakeholders manage the hazards to food security. Here we present an `end-to-end’ methodological construct based on weather indices and machine learning that integrates current understanding of the various interacting systems of climate, crops and the economy to determine short- to long-term risk estimates of crop production loss, in different climate and adaptation scenarios. For provinces north and south of the Yangtze River in China, we have found that risk profiles for crop yields that translate climate into economic variability follow marked regional patterns, shaped by drivers of continental-scale climate. We conclude that to be cost-effective, region-specific policies have to be tailored to optimally combine different categories of risk management instruments.

  11. SciBox, an end-to-end automated science planning and commanding system

    NASA Astrophysics Data System (ADS)

    Choo, Teck H.; Murchie, Scott L.; Bedini, Peter D.; Steele, R. Josh; Skura, Joseph P.; Nguyen, Lillian; Nair, Hari; Lucks, Michael; Berman, Alice F.; McGovern, James A.; Turner, F. Scott

    2014-01-01

    SciBox is a new technology for planning and commanding science operations for Earth-orbital and planetary space missions. It has been incrementally developed since 2001 and demonstrated on several spaceflight projects. The technology has matured to the point that it is now being used to plan and command all orbital science operations for the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) mission to Mercury. SciBox encompasses the derivation of observing sequences from science objectives, the scheduling of those sequences, the generation of spacecraft and instrument commands, and the validation of those commands prior to uploading to the spacecraft. Although the process is automated, science and observing requirements are incorporated at each step by a series of rules and parameters to optimize observing opportunities, which are tested and validated through simulation and review. Except for limited special operations and tests, there is no manual scheduling of observations or construction of command sequences. SciBox reduces the lead time for operations planning by shortening the time-consuming coordination process, reduces cost by automating the labor-intensive processes of human-in-the-loop adjudication of observing priorities, reduces operations risk by systematically checking constraints, and maximizes science return by fully evaluating the trade space of observing opportunities to meet MESSENGER science priorities within spacecraft recorder, downlink, scheduling, and orbital-geometry constraints.

  12. Exploring Two Approaches for an End-to-End Scientific Analysis Workflow

    DOE PAGESBeta

    Dodelson, Scott; Kent, Steve; Kowalkowski, Jim; Paterno, Marc; Sehrish, Saba

    2015-01-01

    The advance of the scientific discovery process is accomplished by the integration of independently-developed programs run on disparate computing facilities into coherent workflows usable by scientists who are not experts in computing. For such advancement, we need a system which scientists can use to formulate analysis workflows, to integrate new components to these workflows, and to execute different components on resources that are best suited to run those components. In addition, we need to monitor the status of the workflow as components get scheduled and executed, and to access the intermediate and final output for visual exploration and analysis. Finally,more » it is important for scientists to be able to share their workflows with collaborators. Moreover we have explored two approaches for such an analysis framework for the Large Synoptic Survey Telescope (LSST) Dark Energy Science Collaboration (DESC), the first one is based on the use and extension of Galaxy, a web-based portal for biomedical research, and the second one is based on a programming language, Python. In our paper, we present a brief description of the two approaches, describe the kinds of extensions to the Galaxy system we have found necessary in order to support the wide variety of scientific analysis in the cosmology community, and discuss how similar efforts might be of benefit to the HEP community.« less

  13. End-to-End Data Movement Using MPI-IO Over Routed Terabots Infrastructures

    SciTech Connect

    Vallee, Geoffroy R; Atchley, Scott; Kim, Youngjae; Shipman, Galen M

    2013-01-01

    Scientific discovery is nowadays driven by large-scale simulations running on massively parallel high-performance computing (HPC) systems. These applications each generate a large amount of data, which then needs to be post-processed for example for data mining or visualization. Unfortunately, the computing platform used for post processing might be different from the one on which the data is initially generated, introducing the challenge of moving large amount of data between computing platforms. This is especially challenging when these two platforms are geographically separated since the data needs to be moved between computing facilities. This is even more critical when scientists tightly couple their domain specific applications with a post processing application. The paper presents a solution for the data transfer between MPI applications using a dedicated wide area network (WAN) terabit infrastructure. The proposed solution is based on parallel access to data files and the Message Passing Interface (MPI) over the Common Communication Infrastructure (CCI) for the data transfer over a routed infrastructure. In the context of this research, the Energy Sciences Network (ESnet) of the U.S. Department of Energy (DOE) is targeted for the transfer of data between DOE national laboratories.

  14. End-to-end quality measure for transmission of compressed imagery over a noisy coded channel

    NASA Technical Reports Server (NTRS)

    Korwar, V. N.; Lee, P. J.

    1981-01-01

    For the transmission of imagery at high data rates over large distances with limited power and system gain, it is usually necessary to compress the data before transmitting it over a noisy channel that uses channel coding to reduce the effect of noise introduced errors. Both compression and channel noise introduce distortion into the imagery. In order to design a communication link that provides adequate quality of received images, it is necessary first to define some suitable distortion measure that accounts for both these kinds of distortion and then to perform various tradeoffs to arrive at system parameter values that will provide a sufficiently low level of received image distortion. The overall mean square error is used as the distortion measure and a description of how to perform these tradeoffs are included.

  15. End-to-end design consideration of a radar altimeter for terrain-aided navigation

    NASA Astrophysics Data System (ADS)

    Chun, Joohwan; Choi, Sanghyouk; Paek, Inchan; Park, Dongmin; Yoo, Kyungju

    2013-10-01

    We present a preliminary simulation study of an interferometric SAR altimeter for the terrain-aided navigation application. Our simulation includes raw SAR data generation, azimuth compression, leading edge detection of the echo signal, maximum likelihood angle estimation and the Bayesian state estimation. Sour results show that radar altimeter performance can be improved with the feedback loop from the rear-end navigation part.

  16. Data compression: The end-to-end information systems perspective for NASA space science missions

    NASA Technical Reports Server (NTRS)

    Tai, Wallace

    1991-01-01

    The unique characteristics of compressed data have important implications to the design of space science data systems, science applications, and data compression techniques. The sequential nature or data dependence between each of the sample values within a block of compressed data introduces an error multiplication or propagation factor which compounds the effects of communication errors. The data communication characteristics of the onboard data acquisition, storage, and telecommunication channels may influence the size of the compressed blocks and the frequency of included re-initialization points. The organization of the compressed data are continually changing depending on the entropy of the input data. This also results in a variable output rate from the instrument which may require buffering to interface with the spacecraft data system. On the ground, there exist key tradeoff issues associated with the distribution and management of the science data products when data compression techniques are applied in order to alleviate the constraints imposed by ground communication bandwidth and data storage capacity.

  17. Independent SCPS-TP development for fault-tolerant, end-to-end communication architectures

    NASA Astrophysics Data System (ADS)

    Edwards, E.; Lamorie, J.; Younghusband, D.; Brunet, C.; Hartman, L.

    2002-07-01

    A fully networked architecture provides for the distribution of computing elements, of all mission components, through the spacecraft. Each node is individually addressable through the network, and behaves as an independent entity. This level of communication also supports individualized Command and Data Handling (C&DH), as well as one-to-one transactions between spacecraft nodes and individual ground segment users. To be effective, fault-tolerance must be applied at the network data transport level, as well as the supporting layers below it. If the network provides fail-safe characteristics independent of the mission applications being executed, then developers need not build in their own systems to ensure network reliability. The Space Communications Protocol Standards (SCPS) were developed to provide robust communications in a space environment, while retaining compatibility with Internet data transport at the ground segment. Although SCPS is a standard of the Consultative Committee for Space Data Systems (CCSDS), the adoption of SCPS was initially delayed by US export regulations that prevented the distribution of reference code. This paper describes the development and test of a fully independent implementation of the SCSP Transport Protocol, SCPS-TP, which has been derived directly from the CCSDS specification. The performance of the protocol is described for a set of geostationary satellite tests, and these results will be compared with those derived from network simulation and laboratory emulation. The work is placed in the context of a comprehensive, fault-tolerant network that potentially surpasses the failsafe performance of a traditional spacecraft control system under similar circumstances.

  18. EQUIP: end-to-end quantification of uncertainty for impacts prediction

    NASA Astrophysics Data System (ADS)

    Morse, A. P.; Challinor, A. J.; Equip Consortium

    2010-12-01

    Inherent uncertainties in climate prediction present a serious challenge to attempts to assess future impacts and adaptation options. Such assessments are critical to any policy decisions regarding investment in resources to ensure human and environmental wellbeing in the face of environmental change and a growing population. Current methods for quantifying uncertainty in projections of climate and its impacts tend to focus first on taking full account of uncertainty, with a subsequent step assessing utility. We argue that a new approach is required, whereby climate and impacts models are used to develop risk-based prediction systems that focus on the information content of models and utility for decision-making. Preliminary steps in this direction are explored, principally using the example of climate-induced changes in crop yield. The relative contribution of uncertainty in crop and climate simulation to the total uncertainty in projected yield changes is examined. A focus on governing bio-physical processes across a number of crop models is used to characterise the robustness of the results. Further development of this approach relies on the development of decision-focussed techniques that analyse sources of uncertainty and assess and improve the information content of models of climate and its impacts. Such an approach is significantly different from tagging impacts models onto climate models. It implies substantial interaction with other organisations and stakeholders from development NGOs to the insurance sector and policy makers. These interactions should be aimed at ensuring that the principal lead-times, and formats, for the impact projections are those relevant to decision-making. The EQUIP project, and its associated open network of scientists, aims to develop the approach outlined above. The project is examining the cascade of uncertainty from climate to impacts by conducting integrated analyses of a range of sectors, principally crops, marine ecosystems, water management, heat waves and droughts. The research includes assessment of the information content of climate model projections, combination of climate models and data-driven models to support decisions, and evaluation of the quality of climate and impacts predictions.

  19. End-to-End Network QoS via Scheduling of Flexible Resource Reservation Requests

    SciTech Connect

    Sharma, S.; Katramatos, D.; Yu, D.

    2011-11-14

    Modern data-intensive applications move vast amounts of data between multiple locations around the world. To enable predictable and reliable data transfer, next generation networks allow such applications to reserve network resources for exclusive use. In this paper, we solve an important problem (called SMR3) to accommodate multiple and concurrent network reservation requests between a pair of end-sites. Given the varying availability of bandwidth within the network, our goal is to accommodate as many reservation requests as possible while minimizing the total time needed to complete the data transfers. We first prove that SMR3 is an NP-hard problem. Then we solve it by developing a polynomial-time heuristic, called RRA. The RRA algorithm hinges on an efficient mechanism to accommodate large number of requests by minimizing the bandwidth wastage. Finally, via numerical results, we show that RRA constructs schedules that accommodate significantly larger number of requests compared to other, seemingly efficient, heuristics.

  20. An end-to-end data system for the Gamma-Ray Observatory

    NASA Astrophysics Data System (ADS)

    Hrastar, J.

    A data system, which includes parts in the orbiting Gamma-Ray Observatory and in its associated ground system, has been designed to rapidly deliver autonomous, packeted data to the science users. Data autonomy means all of the data, including auxiliary data, necessary for processing is included in the data packet that leaves the spacecraft. The data packets leaving the spacecraft remain unopened until they reach the user. Handling the data on a packet rather than a byte level allows simpler and generic software. The data goes through the system more quickly. This in turn reduces cost.

  1. Privacy in Pharmacogenetics: An End-to-End Case Study of Personalized Warfarin Dosing

    PubMed Central

    Fredrikson, Matthew; Lantz, Eric; Jha, Somesh; Lin, Simon; Page, David; Ristenpart, Thomas

    2014-01-01

    We initiate the study of privacy in pharmacogenetics, wherein machine learning models are used to guide medical treatments based on a patient’s genotype and background. Performing an in-depth case study on privacy in personalized warfarin dosing, we show that suggested models carry privacy risks, in particular because attackers can perform what we call model inversion: an attacker, given the model and some demographic information about a patient, can predict the patient’s genetic markers. As differential privacy (DP) is an oft-proposed solution for medical settings such as this, we evaluate its effectiveness for building private versions of pharmacogenetic models. We show that DP mechanisms prevent our model inversion attacks when the privacy budget is carefully selected. We go on to analyze the impact on utility by performing simulated clinical trials with DP dosing models. We find that for privacy budgets effective at preventing attacks, patients would be exposed to increased risk of stroke, bleeding events, and mortality. We conclude that current DP mechanisms do not simultaneously improve genomic privacy while retaining desirable clinical efficacy, highlighting the need for new mechanisms that should be evaluated in situ using the general methodology introduced by our work. PMID:27077138

  2. End-to-end information system concept for the Mars Telecommunications Orbiter

    NASA Technical Reports Server (NTRS)

    Breidenthal, Julian C.; Edwards, Charles D.; Greenberg, Edward; Kazz, Greg J.; Noreen, Gary K.

    2006-01-01

    The Mars Telecommunications Orbiter (MTO) was intended to provide high-performance deep space relay links to landers, orbiters, sample-return missions, and approaching spacecraft in the vicinity of Mars, to demostrate interplanetary laser communications, to demonstrate autonomous navigation, and to carry out its own science investigations.

  3. End-to-end information system concept for the Mars Telecommunications Orbiter

    NASA Technical Reports Server (NTRS)

    Bridenthal, Julian C.; Edwards, Charles D.; Greenberg, Edward; Kazz, Greg J.; Noreen, Gary K.

    2006-01-01

    The Mars Telecommunications Orbiter (MTO) was intended to provide high-performance deep space relay links to landers, orbiters, sample-return, missions, and approaching spacecraft in the vicinity of Mars, to demonstrate interplanetary laser communications, to demonstrate autonomous navigation, and to carry out is own science investigations.

  4. An end-to-end pointing budget approach to planetary observing systems with application to EOS

    NASA Technical Reports Server (NTRS)

    Throckmorton, A.

    1993-01-01

    Previously published error budgets have focused on spacecraft error sources for pointing error and have tended to include only spacecraft pointing rather than the ultimate geolocation of each pixel of dam onto a well-defined spot on the surface of the Earth. A systematic approach to geolocation error budgeting, including all contributors in the geolocation process is presented. Its structure allows simultaneous expression of the needs of instrument teams as well as spacecraft design teams. It allows explicit acknowledgement of approximations made for on-board control as well as the ultimate geolocation accuracy achievable after ground processing and exploits the commonality inherent in the on-board and post-processing error budgets. It also includes the uncontrolled and unmeasured spacecraft jitter. This approach can be used to investigate the mission-wide benefit of a variety of design choices, (such as on-board sensing and ground correction of measurements contrasted with on-board correction of measurements). Additionally, in light of increasing accuracy requirements as sensor resolution improves, numerous non-spacecraft contributors to geolocation error are quantified.

  5. The Kepler End-to-End Data Pipeline: From Photons to Far Away Worlds

    NASA Technical Reports Server (NTRS)

    Cooke, Brian; Thompson, Richard; Standley, Shaun

    2012-01-01

    The Kepler mission is described in overview and the Kepler technique for discovering exoplanets is discussed. The design and implementation of the Kepler spacecraft, tracing the data path from photons entering the telescope aperture through raw observation data transmitted to the ground operations team is described. The technical challenges of operating a large aperture photometer with an unprecedented 95 million pixel detector are addressed as well as the onboard technique for processing and reducing the large volume of data produced by the Kepler photometer. The technique and challenge of day-to-day mission operations that result in a very high percentage of time on target is discussed. This includes the day to day process for monitoring and managing the health of the spacecraft, the annual process for maintaining sun on the solar arrays while still keeping the telescope pointed at the fixed science target, the process for safely but rapidly returning to science operations after a spacecraft initiated safing event and the long term anomaly resolution process.The ground data processing pipeline, from the point that science data is received on the ground to the presentation of preliminary planetary candidates and supporting data to the science team for further evaluation is discussed. Ground management, control, exchange and storage of Kepler's large and growing data set is discussed as well as the process and techniques for removing noise sources and applying calibrations to intermediate data products.

  6. An end-to-end workflow for engineering of biological networks from high-level specifications.

    PubMed

    Beal, Jacob; Weiss, Ron; Densmore, Douglas; Adler, Aaron; Appleton, Evan; Babb, Jonathan; Bhatia, Swapnil; Davidsohn, Noah; Haddock, Traci; Loyall, Joseph; Schantz, Richard; Vasilev, Viktor; Yaman, Fusun

    2012-08-17

    We present a workflow for the design and production of biological networks from high-level program specifications. The workflow is based on a sequence of intermediate models that incrementally translate high-level specifications into DNA samples that implement them. We identify algorithms for translating between adjacent models and implement them as a set of software tools, organized into a four-stage toolchain: Specification, Compilation, Part Assignment, and Assembly. The specification stage begins with a Boolean logic computation specified in the Proto programming language. The compilation stage uses a library of network motifs and cellular platforms, also specified in Proto, to transform the program into an optimized Abstract Genetic Regulatory Network (AGRN) that implements the programmed behavior. The part assignment stage assigns DNA parts to the AGRN, drawing the parts from a database for the target cellular platform, to create a DNA sequence implementing the AGRN. Finally, the assembly stage computes an optimized assembly plan to create the DNA sequence from available part samples, yielding a protocol for producing a sample of engineered plasmids with robotics assistance. Our workflow is the first to automate the production of biological networks from a high-level program specification. Furthermore, the workflow's modular design allows the same program to be realized on different cellular platforms simply by swapping workflow configurations. We validated our workflow by specifying a small-molecule sensor-reporter program and verifying the resulting plasmids in both HEK 293 mammalian cells and in E. coli bacterial cells. PMID:23651286

  7. End-to-end observatory software modeling using domain specific languages

    NASA Astrophysics Data System (ADS)

    Filgueira, José M.; Bec, Matthieu; Liu, Ning; Peng, Chien; Soto, José

    2014-07-01

    The Giant Magellan Telescope (GMT) is a 25-meter extremely large telescope that is being built by an international consortium of universities and research institutions. Its software and control system is being developed using a set of Domain Specific Languages (DSL) that supports a model driven development methodology integrated with an Agile management process. This approach promotes the use of standardized models that capture the component architecture of the system, that facilitate the construction of technical specifications in a uniform way, that facilitate communication between developers and domain experts and that provide a framework to ensure the successful integration of the software subsystems developed by the GMT partner institutions.

  8. End-to-end wireless TCP with noncongestion packet loss detection and handling

    NASA Astrophysics Data System (ADS)

    Lee, Jae-Joon; Liu, Fang; Kuo, C.-C. Jay

    2003-07-01

    Traditional TCP performance degrades over lossy links, as the TCP sender assumes that packet loss is caused by congestion in the network path and thus reduces the sending rate by cutting the congestion window multiplicatively, and a mechanism to overcome this limitation is investigated in this research. Our scheme identifies the network path condition to differentiate whether congestion happens or not, and responds differently. The basic idea of separating congestion and non-congestion caused losses is to compare the estimated current available bandwidth and the average available bandwidth. To minimize the effect of temporary fluctuation of measurements, we estimate the available bandwidth with a higher weight on stable measurements and a lower weight on unstable fluctuations. In our scheme, packet loss due to congestion invokes the TCP Newreno procedure. In cases of random loss that is not related to congestion, the multiplicative decrease of the sending rate is avoided to achieve higher throughput. In addition, each duplicate acknowledgement after a fast retransmission will increase the congestion window to fully recover its sending rate. Extensive simulation results show that our differentiation algorithm achieves high accuracy. Accordingly, the TCP connection over lossy link with the proposed scheme provides higher throughput than TCP Newreno.

  9. End-to-end Encryption for SMS Messages in the Health Care Domain.

    PubMed

    Hassinen, Marko; Laitinen, Pertti

    2005-01-01

    The health care domain has a high level of expectation on security and privacy of patient information. The security, privacy, and confidentiality issues are consistent all over the domain. Technical development and increasing use of mobile phones has led us to a situation in which SMS messages are used in the electronic interactions between health care professionals and patients. We will show that it is possible to send, receive and store text messages securely with a mobile phone with no additional hardware required. More importantly we will show that it is possible to obtain a reliable user authentication in systems using text message communication. Programming language Java is used for realization of our goals. This paper describes the general application structure, while details for the technical implementation and encryption methods are described in the referenced articles. We also propose some crucial areas where the implementation of encrypted SMS can solve previous lack of security. PMID:16160278

  10. Exploring Two Approaches for an End-to-End Scientific Analysis Workflow

    NASA Astrophysics Data System (ADS)

    Dodelson, Scott; Kent, Steve; Kowalkowski, Jim; Paterno, Marc; Sehrish, Saba

    2015-12-01

    The scientific discovery process can be advanced by the integration of independently-developed programs run on disparate computing facilities into coherent workflows usable by scientists who are not experts in computing. For such advancement, we need a system which scientists can use to formulate analysis workflows, to integrate new components to these workflows, and to execute different components on resources that are best suited to run those components. In addition, we need to monitor the status of the workflow as components get scheduled and executed, and to access the intermediate and final output for visual exploration and analysis. Finally, it is important for scientists to be able to share their workflows with collaborators. We have explored two approaches for such an analysis framework for the Large Synoptic Survey Telescope (LSST) Dark Energy Science Collaboration (DESC); the first one is based on the use and extension of Galaxy, a web-based portal for biomedical research, and the second one is based on a programming language, Python. In this paper, we present a brief description of the two approaches, describe the kinds of extensions to the Galaxy system we have found necessary in order to support the wide variety of scientific analysis in the cosmology community, and discuss how similar efforts might be of benefit to the HEP community.

  11. Building an advanced wireless end-to-end emergency medical system.

    PubMed

    Saddik, Basema; El-Masri, Samir

    2011-01-01

    Effective communication in healthcare is important and especially critical in emergency situations. In this paper we propose a new comprehensive emergency system which will facilitate the communication process in emergency cases from ambulance dispatch to the patient's arrival and handover in the hospital. The proposed system has been designed to facilitate and computerise all the processes involved in an accident from finding the nearest ambulance through to accessing a patient's online health record which can assist in pre-hospital treatments. The proposed system will also locate the nearest hospital specialising in the patient's condition and will communicate patient identification to the emergency department. The components of the proposed system and the technologies used in building this system are outlined in this paper as well as the challenges expected and proposed solutions to these challenges. PMID:21893922

  12. PICASSO: an end-to-end image simulation tool for space and airborne imaging systems

    NASA Astrophysics Data System (ADS)

    Cota, Stephen A.; Bell, Jabin T.; Boucher, Richard H.; Dutton, Tracy E.; Florio, Christopher J.; Franz, Geoffrey A.; Grycewicz, Thomas J.; Kalman, Linda S.; Keller, Robert A.; Lomheim, Terrence S.; Paulson, Diane B.; Wilkinson, Timothy S.

    2010-06-01

    The design of any modern imaging system is the end result of many trade studies, each seeking to optimize image quality within real world constraints such as cost, schedule and overall risk. Image chain analysis - the prediction of image quality from fundamental design parameters - is an important part of this design process. At The Aerospace Corporation we have been using a variety of image chain analysis tools for many years, the Parameterized Image Chain Analysis & Simulation SOftware (PICASSO) among them. In this paper we describe our PICASSO tool, showing how, starting with a high quality input image and hypothetical design descriptions representative of the current state of the art in commercial imaging satellites, PICASSO can generate standard metrics of image quality in support of the decision processes of designers and program managers alike.

  13. Potential end-to-end imaging information rate advantages of various alternative communication systems

    NASA Technical Reports Server (NTRS)

    Rice, R. F.

    1978-01-01

    Various communication systems were considered which are required to transmit both imaging and a typically error sensitive, class of data called general science/engineering (gse) over a Gaussian channel. The approach jointly treats the imaging and gse transmission problems, allowing comparisons of systems which include various channel coding and data compression alternatives. Actual system comparisons include an Advanced Imaging Communication System (AICS) which exhibits the rather significant potential advantages of sophisticated data compression coupled with powerful yet practical channel coding.

  14. Integrating end-to-end encryption and authentication technology into broadband networks

    SciTech Connect

    Pierson, L.G.

    1995-11-01

    BISDN services will involve the integration of high speed data, voice, and video functionality delivered via technology similar to Asynchronous Transfer Mode (ATM) switching and SONET optical transmission systems. Customers of BISDN services may need a variety of data authenticity and privacy assurances, via Asynchronous Transfer Mode (ATM) services Cryptographic methods can be used to assure authenticity and privacy, but are hard to scale for implementation at high speed. The incorporation of these methods into computer networks can severely impact functionality, reliability, and performance. While there are many design issues associated with the serving of public keys for authenticated signaling and for establishment of session cryptovariables, this paper is concerned with the impact of encryption itself on such communications once the signaling and setup have been completed. Network security protections should be carefully matched to the threats against which protection is desired. Even after eliminating unnecessary protections, the remaining customer-required network security protections can impose severe performance penalties. These penalties (further discussed below) usually involve increased communication processing for authentication or encryption, increased error rate, increased communication delay, and decreased reliability/availability. Protection measures involving encryption should be carefully engineered so as to impose the least performance, reliability, and functionality penalties, while achieving the required security protection. To study these trade-offs, a prototype encryptor/decryptor was developed. This effort demonstrated the viability of implementing certain encryption techniques in high speed networks. The research prototype processes ATM cells in a SONET OC-3 payload. This paper describes the functionality, reliability, security, and performance design trade-offs investigated with the prototype.

  15. End-to-end imaging information rate advantages of various alternative communication systems

    NASA Technical Reports Server (NTRS)

    Rice, R. F.

    1982-01-01

    The efficiency of various deep space communication systems which are required to transmit both imaging and a typically error sensitive class of data called general science and engineering (gse) are compared. The approach jointly treats the imaging and gse transmission problems, allowing comparisons of systems which include various channel coding and data compression alternatives. Actual system comparisons include an advanced imaging communication system (AICS) which exhibits the rather significant advantages of sophisticated data compression coupled with powerful yet practical channel coding. For example, under certain conditions the improved AICS efficiency could provide as much as two orders of magnitude increase in imaging information rate compared to a single channel uncoded, uncompressed system while maintaining the same gse data rate in both systems. Additional details describing AICS compression and coding concepts as well as efforts to apply them are provided in support of the system analysis.

  16. Exploring Two Approaches for an End-to-End Scientific Analysis Workflow

    SciTech Connect

    Dodelson, Scott; Kent, Steve; Kowalkowski, Jim; Paterno, Marc; Sehrish, Saba

    2015-01-01

    The advance of the scientific discovery process is accomplished by the integration of independently-developed programs run on disparate computing facilities into coherent workflows usable by scientists who are not experts in computing. For such advancement, we need a system which scientists can use to formulate analysis workflows, to integrate new components to these workflows, and to execute different components on resources that are best suited to run those components. In addition, we need to monitor the status of the workflow as components get scheduled and executed, and to access the intermediate and final output for visual exploration and analysis. Finally, it is important for scientists to be able to share their workflows with collaborators. Moreover we have explored two approaches for such an analysis framework for the Large Synoptic Survey Telescope (LSST) Dark Energy Science Collaboration (DESC), the first one is based on the use and extension of Galaxy, a web-based portal for biomedical research, and the second one is based on a programming language, Python. In our paper, we present a brief description of the two approaches, describe the kinds of extensions to the Galaxy system we have found necessary in order to support the wide variety of scientific analysis in the cosmology community, and discuss how similar efforts might be of benefit to the HEP community.

  17. An End-to-End Architecture for Science Goal Driven Observing

    NASA Technical Reports Server (NTRS)

    Jones, Jeremy; Grosvenor, Sandy; Koratkar, Anuradha; Memarsadeghi, Nargess; Wolf, Karl; Obenschain, Arthur F. (Technical Monitor)

    2002-01-01

    New observatories will have greater on-board storage capacity and on-board processing capabilities. The new bottleneck will be download capacity. The cost of downlink time and limitations of bandwidth will end the era where all exposure data is downloaded and all data processing is performed on the ground. In addition, observing campaigns involving inherently variable targets will need scheduling flexibility to focus observing time and data download on exposures that are scientifically interesting. The ability to quickly recognize and react to such events by re-prioritizing the observing schedule will be an essential characteristic for maximizing scientific returns. It will also be a step towards increasing spacecraft autonomy, a major goal of NASA's strategic plan. The science goal monitoring (SGM) system is a proof-of-concept effort to address these challenges. We are developing an interactive distributed system that will use on-board processing and storage combined with event-driven interfaces with ground-based processing and operations, to enable fast re-prioritization of observing schedules, and to minimize time spent on non-optimized observations. SGM is initially aimed towards time-tagged observing modes used frequently in spectroscopic studies of varying targets. In particular, the SGM is collaborating with the proposed MIDEX-class mission Kronos team. The variable targets that Kronos seeks to study make an adaptive system such as SGM particularly valuable for achieving mission goals. However, the architecture and interfaces will also be designed for easy adaptability to other observing platforms, including ground-based systems and to work with different scheduling and pipeline processing systems. This talk will focus on our strategy for developing SGM and the technical challenges that we have encountered. We will discuss the SGM architecture as it applies to the Kronos mission and explain how it is scalable to other missions.

  18. Building an End-to-end System for Long Term Soil Monitoring

    NASA Astrophysics Data System (ADS)

    Szlavecz, K.; Terzis, A.; Musaloiu-E., R.; Cogan, J.; Szalay, A.; Gray, J.

    2006-05-01

    We have developed and deployed an experimental soil monitoring system in an urban forest. Wireless sensor nodes collect data on soil temperature, soil moisture, air temperature, and light. Data are uploaded into a SQL Server database, where they are calibrated and reorganized into an OLAP data cube. The data are accessible on-line using a web services interface with various visual tools. Our prototype system of ten nodes has been live since Sep 2005, and in 5 months of operation over 6 million measurements have been collected. At a high level, our experiment was a success: we detected variations in soil condition corresponding to topography and external environmental parameters as expected. However, we encountered a number of challenging technical problems: need for low-level programming at multiple levels, calibration across space and time, and cross- reference of measurements with external sources. Based upon the experience with this system we are now deploying 200 mode nodes with close to a thousand sensors spread over multiple sites in the context of the Baltimore Ecosystem Study LTER. www

  19. Experiments with Memory-to-Memory Coupling for End-to-End fusion Simulation Workflows

    SciTech Connect

    Docan, Ciprian; Zhang, Fan; Parashar, Manish; Cummings, Julian; Podhorszki, Norbert; Klasky, Scott A

    2010-01-01

    Scientific applications are striving to accurately simulate multiple interacting physical processes that comprise complex phenomena being modeled. Efficient and scalable parallel implementations of these coupled simulations present challenging interaction and coordination requirements, especially when the coupled physical processes are computationally heterogeneous and progress at different speeds. In this paper, we present the design, implementation and evaluation of a memory-to-memory coupling framework for coupled scientific simulations on high-performance parallel computing platforms. The framework is driven by the coupling requirements of the Center for Plasma Edge Simulation, and it provides simple coupling abstractions as well as efficient asynchronous (RDMA-based) memory-to-memory data transport mechanisms that complement existing parallel programming systems and data sharing frameworks. The framework enables flexible coupling behaviors that are asynchronous in time and space, and it supports dynamic coupling between heterogeneous simulation processes without enforcing any synchronization constraints. We evaluate the performance and scalability of the coupling framework using a specific coupling scenario, on the Jaguar Cray XT5 system at Oak Ridge National Laboratory.

  20. An end-to-end data system for the Gamma-Ray Observatory

    NASA Technical Reports Server (NTRS)

    Hrastar, J.

    1983-01-01

    A data system, which includes parts in the orbiting Gamma-Ray Observatory and in its associated ground system, has been designed to rapidly deliver autonomous, packeted data to the science users. Data autonomy means all of the data, including auxiliary data, necessary for processing is included in the data packet that leaves the spacecraft. The data packets leaving the spacecraft remain unopened until they reach the user. Handling the data on a packet rather than a byte level allows simpler and generic software. The data goes through the system more quickly. This in turn reduces cost.

  1. Assessing Natural Product-Drug Interactions: An End-to-End Safety Framework.

    PubMed

    Roe, Amy L; Paine, Mary F; Gurley, Bill J; Brouwer, Kenneth R; Jordan, Scott; Griffiths, James C

    2016-04-01

    The use of natural products (NPs), including herbal medicines and other dietary supplements, by North Americans continues to increase across all age groups. This population has access to conventional medications, with significant polypharmacy observed in older adults. Thus, the safety of the interactions between multi-ingredient NPs and drugs is a topic of paramount importance. Considerations such as history of safe use, literature data from animal toxicity and human clinical studies, and NP constituent characterization would provide guidance on whether to assess NP-drug interactions experimentally. The literature is replete with reports of various NP extracts and constituents as potent inhibitors of drug metabolizing enzymes, and transporters. However, without standard methods for NP characterization or in vitro testing, extrapolating these reports to clinically-relevant NP-drug interactions is difficult. This lack of a clear definition of risk precludes clinicians and consumers from making informed decisions about the safety of taking NPs with conventional medications. A framework is needed that describes an integrated robust approach for assessing NP-drug interactions; and, translation of the data into formulation alterations, dose adjustment, labelling, and/or post-marketing surveillance strategies. A session was held at the 41st Annual Summer Meeting of the Toxicology Forum in Colorado Springs, CO, to highlight the challenges and critical components that should be included in a framework approach. PMID:26776752

  2. Assessing the Performance Limits of Internal Coronagraphs Through End-to-End Modeling

    NASA Technical Reports Server (NTRS)

    Krist, John E.; Belikov, Ruslan; Pueyo, Laurent; Mawet, Dimitri P.; Moody, Dwight; Trauger, John T.; Shaklan, Stuart B.

    2013-01-01

    As part of the NASA ROSES Technology Demonstrations for Exoplanet Missions (TDEM) program, we conducted a numerical modeling study of three internal coronagraphs (PIAA, vector vortex, hybrid bandlimited) to understand their behaviors in realistically-aberrated systems with wavefront control (deformable mirrors). This investigation consisted of two milestones: (1) develop wavefront propagation codes appropriate for each coronagraph that are accurate to 1% or better (compared to a reference algorithm) but are also time and memory efficient, and (2) use these codes to determine the wavefront control limits of each architecture. We discuss here how the milestones were met and identify some of the behaviors particular to each coronagraph. The codes developed in this study are being made available for community use. We discuss here results for the HBLC and VVC systems, with PIAA having been discussed in a previous proceeding.

  3. Science and Applications Space Platform (SASP) End-to-End Data System Study

    NASA Technical Reports Server (NTRS)

    Crawford, P. R.; Kasulka, L. H.

    1981-01-01

    The capability of present technology and the Tracking and Data Relay Satellite System (TDRSS) to accommodate Science and Applications Space Platforms (SASP) payload user's requirements, maximum service to the user through optimization of the SASP Onboard Command and Data Management System, and the ability and availability of new technology to accommodate the evolution of SASP payloads were assessed. Key technology items identified to accommodate payloads on a SASP were onboard storage devices, multiplexers, and onboard data processors. The primary driver is the limited access to TDRSS for single access channels due to sharing with all the low Earth orbit spacecraft plus shuttle. Advantages of onboard data processing include long term storage of processed data until TRDSS is accessible, thus reducing the loss of data, eliminating large data processing tasks at the ground stations, and providing a more timely access to the data.

  4. Sensory Recovery Outcome after Digital Nerve Repair in Relation to Different Reconstructive Techniques: Meta-Analysis and Systematic Review

    PubMed Central

    Wolf, Petra; Harder, Yves; Kern, Yasmin; Paprottka, Philipp M.; Machens, Hans-Günther; Lohmeyer, Jörn A.

    2013-01-01

    Good clinical outcome after digital nerve repair is highly relevant for proper hand function and has a significant socioeconomic impact. However, level of evidence for competing surgical techniques is low. The aim is to summarize and compare the outcomes of digital nerve repair with different methods (end-to-end and end-to-side coaptations, nerve grafts, artificial conduit-, vein-, muscle, and muscle-in-vein reconstructions, and replantations) to provide an aid for choosing an individual technique of nerve reconstruction and to create reference values of standard repair for nonrandomized clinical studies. 87 publications including 2,997 nerve repairs were suitable for a precise evaluation. For digital nerve repairs there was practically no particular technique superior to another. Only end-to-side coaptation had an inferior two-point discrimination in comparison to end-to-end coaptation or nerve grafting. Furthermore, this meta-analysis showed that youth was associated with an improved sensory recovery outcome in patients who underwent digital replantation. For end-to-end coaptations, recent publications had significantly better sensory recovery outcomes than older ones. Given minor differences in outcome, the main criteria in choosing an adequate surgical technique should be gap length and donor site morbidity caused by graft material harvesting. Our clinical experience was used to provide a decision tree for digital nerve repair. PMID:23984064

  5. Channeled spectropolarimetry using iterative reconstruction

    NASA Astrophysics Data System (ADS)

    Lee, Dennis J.; LaCasse, Charles F.; Craven, Julia M.

    2016-05-01

    Channeled spectropolarimeters (CSP) measure the polarization state of light as a function of wavelength. Conventional Fourier reconstruction suffers from noise, assumes the channels are band-limited, and requires uniformly spaced samples. To address these problems, we propose an iterative reconstruction algorithm. We develop a mathematical model of CSP measurements and minimize a cost function based on this model. We simulate a measured spectrum using example Stokes parameters, from which we compare conventional Fourier reconstruction and iterative reconstruction. Importantly, our iterative approach can reconstruct signals that contain more bandwidth, an advancement over Fourier reconstruction. Our results also show that iterative reconstruction mitigates noise effects, processes non-uniformly spaced samples without interpolation, and more faithfully recovers the ground truth Stokes parameters. This work offers a significant improvement to Fourier reconstruction for channeled spectropolarimetry.

  6. Shuttle spectrum despreader

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The results of the spread spectrum despreader project are reported and three principal products are designed and tested. The products are, (1) a spread spectrum despreader breadboard, (2) associated test equipment consisting of a spectrum spreader and bit reconstruction/error counter and (3) paper design of a Ku-band receiver which would incorporate the despreader as a principal subsystem. The despreader and test set are designed for maximum flexibility. A choice of unbalanced quadriphase or biphase shift keyed data modulation is available. Selectable integration time and threshold voltages on the despreader further lend true usefulness as laboratory test equipment to the delivered hardware.

  7. Multi time-step wavefront reconstruction for tomographic adaptive-optics systems.

    PubMed

    Ono, Yoshito H; Akiyama, Masayuki; Oya, Shin; Lardiére, Olivier; Andersen, David R; Correia, Carlos; Jackson, Kate; Bradley, Colin

    2016-04-01

    In tomographic adaptive-optics (AO) systems, errors due to tomographic wavefront reconstruction limit the performance and angular size of the scientific field of view (FoV), where AO correction is effective. We propose a multi time-step tomographic wavefront reconstruction method to reduce the tomographic error by using measurements from both the current and previous time steps simultaneously. We further outline the method to feed the reconstructor with both wind speed and direction of each turbulence layer. An end-to-end numerical simulation, assuming a multi-object AO (MOAO) system on a 30 m aperture telescope, shows that the multi time-step reconstruction increases the Strehl ratio (SR) over a scientific FoV of 10 arc min in diameter by a factor of 1.5-1.8 when compared to the classical tomographic reconstructor, depending on the guide star asterism and with perfect knowledge of wind speeds and directions. We also evaluate the multi time-step reconstruction method and the wind estimation method on the RAVEN demonstrator under laboratory setting conditions. The wind speeds and directions at multiple atmospheric layers are measured successfully in the laboratory experiment by our wind estimation method with errors below 2  ms-1. With these wind estimates, the multi time-step reconstructor increases the SR value by a factor of 1.2-1.5, which is consistent with a prediction from the end-to-end numerical simulation. PMID:27140785

  8. New Portal-Superior Mesenteric Vein Reconstructions Using First Jejunal Vein Flap in Pancreaticoduodenectomy.

    PubMed

    Takemura, Nobuyuki; Miki, Kenji; Kosuge, Tomoo

    2016-06-01

    Pancreaticoduodenectomy (PD) is the only potential treatment for pancreatic head adenocarcinomas, which are sometimes located close to or invade the portal-superior mesenteric vein (PSMV). Surgeons often attempt to obtain a negative resectional margin after resection of the PSMV. This attempt requires PSMV reconstruction through graft replacements or end-to-end anastomosis; however, possible complications should be concerned including anastomosis stenosis, damage to some of the PSMV branches, prosthetic graft infection, and that associated with autologous graft harvesting. The first jejunal artery and vein are often resected in PD with the intent of lymphadenectomy. In this study, jejunal vein flap was used for PSMV reconstruction without causing damage to any of the PSMV branches in two patients. Here, we describe the new methods of PSMV reconstruction using first jejunal vein flap in PD. PMID:26801505

  9. Wavefront reconstruction for extremely large telescopes via CuRe with domain decomposition.

    PubMed

    Rosensteiner, Matthias

    2012-11-01

    The Cumulative Reconstructor is an accurate, extremely fast reconstruction algorithm for Shack-Hartmann wavefront sensor data. But it has shown an unacceptable high noise propagation for large apertures. Therefore, in this paper we describe a domain decomposition approach to deal with this drawback. We show that this adaptation of the algorithm gives the same reconstruction quality as the original algorithm and leads to a significant improvement with respect to noise propagation. The method is combined with an integral control and compared to the classical matrix vector multiplication algorithm on an end-to-end simulation of a single conjugate adaptive optics system. The reconstruction time is 20n (number of subapertures), and the method is parallelizable. PMID:23201793

  10. Success of free flap anastomoses performed within the zone of trauma in acute lower limb reconstruction.

    PubMed

    Bendon, Charlotte L; Giele, Henk P

    2016-07-01

    Traditionally, in free flap cover of lower limb injuries, every attempt is made to perform anastomoses proximal to the zone of injury. We report on the success of anastomoses within the zone of trauma, at the level of the fracture, avoiding further dissection and exposure. The records of free flap reconstructions for fractures of the lower extremity at a tertiary trauma centre between 2004 and 2010 were retrospectively reviewed. A total of 48 lower limb fractures required free flap reconstruction, performed at 28 days post injury (0-275 days). Anastomoses were proximal (21), distal (5) or within the zone of trauma (22). There was no significant difference (p > 0.05) in return to theatre, revision of anastomosis or flap survival between groups. Of the 22 performed within the zone of injury, five returned to theatre but only two for revision of anastomosis and 20 (91%) of these flaps survived. Of the 48 free flaps, arterial anastomoses were end to end in 34 (71%) and end to side in 14 (30%). There was no significant difference (p > 0.05) in return to theatre, revision of anastomosis or flap survival between the end-to-end and end-to-side groups. There was a tendency for arterial anastomoses to be performed end to end outside the zone of trauma (23/26) compared to within the zone of trauma (11/22). Our data suggest that free flap anastomoses can be performed safely in the zone of trauma in lower limb injuries. PMID:27108076

  11. Popliteal pseudoaneurysm after arthroscopic posterior cruciate ligament reconstruction.

    PubMed

    van Dorp, Karin B; Breugem, Stefan J M; Driessen, Marcel J M

    2014-09-01

    This report presents the case of a 30-year-old motocross (BMX) cyclist with a third-degree posterior cruciate ligament rupture. The technique used for reconstruction was the transtibial single-bundle autologous hamstring technique. Unfortunately, the procedure was complicated by a popliteal pseudoaneurysm, which was located in line with the tibial canal. The pseudoaneurysm was treated with an end-to-end anastomosis and the patient recovered without further complaints. In this case, the popliteal artery was damaged most probably by the edge of the reamer or the guide wire during removal. Vascular complications can be limb- and life-threatening. This case report aims to increase the awareness of this serious complication with a review of the literature. PMID:25229050

  12. Penile Reconstruction

    PubMed Central

    Salgado, Christopher J.; Chim, Harvey; Tang, Jennifer C.; Monstrey, Stan J.; Mardini, Samir

    2011-01-01

    A variety of surgical options exists for penile reconstruction. The key to success of therapy is holistic management of the patient, with attention to the psychological aspects of treatment. In this article, we review reconstructive modalities for various types of penile defects inclusive of partial and total defects as well as the buried penis, and also describe recent basic science advances, which may promise new options for penile reconstruction. PMID:22851914

  13. Zellweger Spectrum

    MedlinePlus

    ... the Zellweger spectrum result from defects in the assembly of a cellular structure called the peroxisome, and ... Zellweger spectrum are caused by defects in the assembly of the peroxisome. There are at least 12 ...

  14. Primordial power spectrum from Planck

    NASA Astrophysics Data System (ADS)

    Hazra, Dhiraj Kumar; Shafieloo, Arman; Souradeep, Tarun

    2014-11-01

    Using modified Richardson-Lucy algorithm we reconstruct the primordial power spectrum (PPS) from Planck Cosmic Microwave Background (CMB) temperature anisotropy data. In our analysis we use different combinations of angular power spectra from Planck to reconstruct the shape of the primordial power spectrum and locate possible features. Performing an extensive error analysis we found the dip near l ~ 750-850 represents the most prominent feature in the data. Feature near l ~ 1800-2000 is detectable with high confidence only in 217 GHz spectrum and is apparently consequence of a small systematic as described in the revised Planck 2013 papers. Fixing the background cosmological parameters and the foreground nuisance parameters to their best fit baseline values, we report that the best fit power law primordial power spectrum is consistent with the reconstructed form of the PPS at 2σ C.L. of the estimated errors (apart from the local features mentioned above). As a consistency test, we found the reconstructed primordial power spectrum from Planck temperature data can also substantially improve the fit to WMAP-9 angular power spectrum data (with respect to power-law form of the PPS) allowing an overall amplitude shift of ~ 2.5%. In this context low-l and 100 GHz spectrum from Planck which have proper overlap in the multipole range with WMAP data found to be completely consistent with WMAP-9 (allowing amplitude shift). As another important result of our analysis we do report the evidence of gravitational lensing through the reconstruction analysis. Finally we present two smooth form of the PPS containing only the important features. These smooth forms of PPS can provide significant improvements in fitting the data (with respect to the power law PPS) and can be helpful to give hints for inflationary model building.

  15. Primordial power spectrum from Planck

    SciTech Connect

    Hazra, Dhiraj Kumar; Shafieloo, Arman; Souradeep, Tarun E-mail: arman@apctp.org

    2014-11-01

    Using modified Richardson-Lucy algorithm we reconstruct the primordial power spectrum (PPS) from Planck Cosmic Microwave Background (CMB) temperature anisotropy data. In our analysis we use different combinations of angular power spectra from Planck to reconstruct the shape of the primordial power spectrum and locate possible features. Performing an extensive error analysis we found the dip near ℓ ∼ 750–850 represents the most prominent feature in the data. Feature near ℓ ∼ 1800–2000 is detectable with high confidence only in 217 GHz spectrum and is apparently consequence of a small systematic as described in the revised Planck 2013 papers. Fixing the background cosmological parameters and the foreground nuisance parameters to their best fit baseline values, we report that the best fit power law primordial power spectrum is consistent with the reconstructed form of the PPS at 2σ C.L. of the estimated errors (apart from the local features mentioned above). As a consistency test, we found the reconstructed primordial power spectrum from Planck temperature data can also substantially improve the fit to WMAP-9 angular power spectrum data (with respect to power-law form of the PPS) allowing an overall amplitude shift of ∼ 2.5%. In this context low-ℓ and 100 GHz spectrum from Planck which have proper overlap in the multipole range with WMAP data found to be completely consistent with WMAP-9 (allowing amplitude shift). As another important result of our analysis we do report the evidence of gravitational lensing through the reconstruction analysis. Finally we present two smooth form of the PPS containing only the important features. These smooth forms of PPS can provide significant improvements in fitting the data (with respect to the power law PPS) and can be helpful to give hints for inflationary model building.

  16. Penile reconstruction

    PubMed Central

    Garaffa, Giulio; Sansalone, Salvatore; Ralph, David J

    2013-01-01

    During the most recent years, a variety of new techniques of penile reconstruction have been described in the literature. This paper focuses on the most recent advances in male genital reconstruction after trauma, excision of benign and malignant disease, in gender reassignment surgery and aphallia with emphasis on surgical technique, cosmetic and functional outcome. PMID:22426595

  17. Accelerating Advanced MRI Reconstructions on GPUs

    PubMed Central

    Stone, S.S.; Haldar, J.P.; Tsao, S.C.; Hwu, W.-m.W.; Sutton, B.P.; Liang, Z.-P.

    2008-01-01

    Computational acceleration on graphics processing units (GPUs) can make advanced magnetic resonance imaging (MRI) reconstruction algorithms attractive in clinical settings, thereby improving the quality of MR images across a broad spectrum of applications. This paper describes the acceleration of such an algorithm on NVIDIA’s Quadro FX 5600. The reconstruction of a 3D image with 1283 voxels achieves up to 180 GFLOPS and requires just over one minute on the Quadro, while reconstruction on a quad-core CPU is twenty-one times slower. Furthermore, relative to the true image, the error exhibited by the advanced reconstruction is only 12%, while conventional reconstruction techniques incur error of 42%. PMID:21796230

  18. Assessment of Vascular Injuries and Reconstruction

    PubMed Central

    Baghi, Iraj; Herfatkar, Mohammad Rasool; Shokrgozar, Leila; Poor-Rasuli, Zahra; Aghajani, Fatemeh

    2015-01-01

    Background: Trauma is the third leading cause of death. In this regard, vascular injury plays a leading role in of morbidity and mortality rates. Objectives: The present study aimed to assess the prevalence of vascular injuries and results of vascular reconstruction at a referral hospital in northern Iran. Patients and Methods: A retrospective observational study assessed 88 consecutive patients with vascular injury admitted to Poursina Hospital, Rasht in northern Iran, from October 2007 to October 2009. All study information was collected retrospectively from hospital charts. Results: Most of the affected patients (87/88) were male with a mean age of 29.12 ± 11.20 years. The mechanism of injury in 39.8% was blunt trauma and penetrating trauma in the rest. Of the 53 injured by penetrating trauma (60.2%), the most common cause was stabbing (94.3%). The most common cause of blunt trauma was road traffic accidents (93.1%). The most common mechanism for vascular injuries in upper extremities was penetrating trauma (86.0%) and in lower extremities was blunt trauma (60.0%). Fasciotomy was performed in 16 patients (18.2%) mostly in the lower extremities. Major amputation was required in 10% of the patients. In upper extremities, the most common type of revascularization was end to end anastomosis, followed by inter-position graft. The most common type of reconstruction in the lower extremity was bypass graft. All patients who underwent major amputation were admitted to the center with a delay of more than 6 hours after injury. Conclusions: Major vascular injuries in our center occurred in young men, frequently because of stab wounds. Popliteal injuries mostly caused by motor vehicle accidents was the second most common arterial injury, followed by combined ulnar and radial injuries. Vascular reconstruction in the first hours after trauma may prevent many unnecessary and preventable amputation procedures. PMID:26839869

  19. Breast reconstruction.

    PubMed

    DellaCroce, Frank J; Wolfe, Emily T

    2013-04-01

    As diagnostic technology has progressed and the understanding of the disease process has evolved, the number of mastectomies performed in the United States has increased. Breast reconstructive techniques have commensurately become more sophisticated along the same timeline. The result is that those facing mastectomy have the potential to simultaneously retain physical beauty and wholeness. Only 33% of women who are otherwise candidates for immediate reconstruction at the time of mastectomy choose reconstruction. Patients generally have a high level of satisfaction with the option they choose, contributing to a feeling of overall recovery and physical and emotional wholeness. PMID:23464695

  20. Microtia reconstruction: autologous rib and alloplast techniques.

    PubMed

    Cabin, Jonathan A; Bassiri-Tehrani, Michael; Sclafani, Anthony P; Romo, Thomas

    2014-11-01

    Microtia represents a spectrum of maldevelopment of the external ear. Reconstructive techniques may utilize an autogenous rib cartilage framework and require 2-4 stages; alternatively, an alloplastic framework can be used and typically requires 1-2 stages. Successful reconstruction of microtia with either technique can provide a significant quality of life improvement, and both techniques are described in this article. PMID:25444733

  1. Iterative reconstruction methods in atmospheric tomography: FEWHA, Kaczmarz and Gradient-based algorithm

    NASA Astrophysics Data System (ADS)

    Ramlau, R.; Saxenhuber, D.; Yudytskiy, M.

    2014-07-01

    The problem of atmospheric tomography arises in ground-based telescope imaging with adaptive optics (AO), where one aims to compensate in real-time for the rapidly changing optical distortions in the atmosphere. Many of these systems depend on a sufficient reconstruction of the turbulence profiles in order to obtain a good correction. Due to steadily growing telescope sizes, there is a strong increase in the computational load for atmospheric reconstruction with current methods, first and foremost the MVM. In this paper we present and compare three novel iterative reconstruction methods. The first iterative approach is the Finite Element- Wavelet Hybrid Algorithm (FEWHA), which combines wavelet-based techniques and conjugate gradient schemes to efficiently and accurately tackle the problem of atmospheric reconstruction. The method is extremely fast, highly flexible and yields superior quality. Another novel iterative reconstruction algorithm is the three step approach which decouples the problem in the reconstruction of the incoming wavefronts, the reconstruction of the turbulent layers (atmospheric tomography) and the computation of the best mirror correction (fitting step). For the atmospheric tomography problem within the three step approach, the Kaczmarz algorithm and the Gradient-based method have been developed. We present a detailed comparison of our reconstructors both in terms of quality and speed performance in the context of a Multi-Object Adaptive Optics (MOAO) system for the E-ELT setting on OCTOPUS, the ESO end-to-end simulation tool.

  2. Off-axis point spread function reconstruction from a dual deformable mirror adaptive optics system

    NASA Astrophysics Data System (ADS)

    Keskin, O.; Conan, R.; Bradley, C.; Blain, C.

    2008-07-01

    In AO applications, PSF reconstruction is used in calibrating image analysis techniques for astrometry, and in the deconvolution of images to enhance their contrast. The partial correction provided by the AO system is due to the finite sampling of the wavefront sensor, the DM (limited number of freedoms on the DM, i.e., the number of actuators) and the finite bandwidth of the control system. Furthermore, the correction provided by an AO system degrades across the field of view, depending on the angular separation between the guide star and the target object (anisoplanatism). In this paper, an end to end numerical model of an off-axis dual DM AO system has been implemented to accommodate for the anisoplanatic errors that degrade the performance of AO systems at greater angular distances from the guide star. An improved off-axis PSF reconstruction methodology has been developed and numerically evaluated for the dual DM (Woofer/Tweeter) off-axis AO architecture.

  3. Optimal reconstruction for closed-loop ground-layer adaptive optics with elongated spots.

    PubMed

    Béchet, Clémentine; Tallon, Michel; Tallon-Bosc, Isabelle; Thiébaut, Éric; Le Louarn, Miska; Clare, Richard M

    2010-11-01

    The design of the laser-guide-star-based adaptive optics (AO) systems for the Extremely Large Telescopes requires careful study of the issue of elongated spots produced on Shack-Hartmann wavefront sensors. The importance of a correct modeling of the nonuniformity and correlations of the noise induced by this elongation has already been demonstrated for wavefront reconstruction. We report here on the first (to our knowledge) end-to-end simulations of closed-loop ground-layer AO with laser guide stars with such an improved noise model. The results are compared with the level of performance predicted by a classical noise model for the reconstruction. The performance is studied in terms of ensquared energy and confirms that, thanks to the improved noise model, central or side launching of the lasers does not affect the performance with respect to the laser guide stars' flux. These two launching schemes also perform similarly whatever the atmospheric turbulence strength. PMID:21045872

  4. ACL reconstruction

    MedlinePlus

    ... Tissue taken from a donor is called an allograft. The procedure is usually performed with the help ... This increases the chance you may have a meniscus tear. ACL reconstruction may be used for these ...

  5. [Eyebrow reconstruction].

    PubMed

    Baraër, F; Darsonval, V; Lejeune, F; Bochot-Hermouet, B; Rousseau, P

    2013-10-01

    The eyebrow is an essential anatomical area, from a social point of view, so its reconstruction, in case of skin defect, must be as meticulous as possible, with the less residual sequela. Capillary density extremely varies from one person to another and the different methods of restoration of this area should absolutely take this into consideration. We are going to review the various techniques of reconstruction, according to the sex and the surface to cover. PMID:23896574

  6. Bayesian reconstruction of projection reconstruction NMR (PR-NMR).

    PubMed

    Yoon, Ji Won

    2014-11-01

    Projection reconstruction nuclear magnetic resonance (PR-NMR) is a technique for generating multidimensional NMR spectra. A small number of projections from lower-dimensional NMR spectra are used to reconstruct the multidimensional NMR spectra. In our previous work, it was shown that multidimensional NMR spectra are efficiently reconstructed using peak-by-peak based reversible jump Markov chain Monte Carlo (RJMCMC) algorithm. We propose an extended and generalized RJMCMC algorithm replacing a simple linear model with a linear mixed model to reconstruct close NMR spectra into true spectra. This statistical method generates samples in a Bayesian scheme. Our proposed algorithm is tested on a set of six projections derived from the three-dimensional 700 MHz HNCO spectrum of a protein HasA. PMID:25218584

  7. Spectrum Recombination.

    ERIC Educational Resources Information Center

    Greenslade, Thomas B., Jr.

    1984-01-01

    Describes several methods of executing lecture demonstrations involving the recombination of the spectrum. Groups the techniques into two general classes: bringing selected portions of the spectrum together using lenses or mirrors and blurring the colors by rapid movement or foreshortening. (JM)

  8. PSF reconstruction for MUSE in wide field mode

    NASA Astrophysics Data System (ADS)

    Villecroze, R.; Fusco, Thierry; Bacon, Roland; Madec, Pierre-Yves

    2012-07-01

    The resolution of ground-based telescopes is dramatically limited by the atmospheric turbulence.. Adaptative optics (AO) is a real-time opto-mechanical approach which allows to correct for the turbulence effect and to reach the ultimate diffraction limit astronomical telescopes and their associated instrumentation. Nevertheless, the AO correction is never perfect especially when it has to deal with large Field of View (FoV). Hence, a posteriori image processing really improves the final estimation of astrophysical data. Such techniques require an accurate knowledge of the system response at any position in the FoV The purpose of this work is then the estimation of the AO response in the particular case of the MUSE [1] /GALACSI [2] instrument (a 3D mult-object spectrograph combined with a Laser-assisted wide field AO system which will be installed at the VLT in 2013). Using telemetry data coming from both AO Laser and natural guide stars, a Point Spread Function (PSF) is derived at any location of the FoV and for every wavelength of the MUSE spectrograph. This document presents the preliminary design of the MUSE WFM PSF reconstruction process. The various hypothesis and approximations are detailed and justified. A first description of the overall process is proposed. Some alternative strategies to improve the performance (in terms of computation time and storage) are described and have been implemented. Finally, after a validation of the proposed algorithm using end-to-end models, a performance analysis is conducted (with the help of a full end-to-end model). This performance analysis will help us to populate an exhaustive error budget table.

  9. Tracking ocean wave spectrum from SAR images

    NASA Technical Reports Server (NTRS)

    Goldfinger, A. D.; Beal, R. C.; Monaldo, F. M.; Tilley, D. G.

    1984-01-01

    An end to end algorithm for recovery of ocean wave spectral peaks from Synthetic Aperture Radar (SAR) images is described. Current approaches allow precisions of 1 percent in wave number, and 0.6 deg in direction.

  10. Reconstructing Validity

    ERIC Educational Resources Information Center

    Moss, Pamela A.

    2007-01-01

    In response to Lissitz and Samuelsen (2007), the author reconstructs the historical arguments for the more comprehensive unitary concept of validity and the principles of scientific inquiry underlying it. Her response is organized in terms of four questions: (a) How did validity in educational measurement come to be conceptualized as unitary, and…

  11. Vaginal reconstruction

    SciTech Connect

    Lesavoy, M.A.

    1985-05-01

    Vaginal reconstruction can be an uncomplicated and straightforward procedure when attention to detail is maintained. The Abbe-McIndoe procedure of lining the neovaginal canal with split-thickness skin grafts has become standard. The use of the inflatable Heyer-Schulte vaginal stent provides comfort to the patient and ease to the surgeon in maintaining approximation of the skin graft. For large vaginal and perineal defects, myocutaneous flaps such as the gracilis island have been extremely useful for correction of radiation-damaged tissue of the perineum or for the reconstruction of large ablative defects. Minimal morbidity and scarring ensue because the donor site can be closed primarily. With all vaginal reconstruction, a compliant patient is a necessity. The patient must wear a vaginal obturator for a minimum of 3 to 6 months postoperatively and is encouraged to use intercourse as an excellent obturator. In general, vaginal reconstruction can be an extremely gratifying procedure for both the functional and emotional well-being of patients.

  12. Project Reconstruct.

    ERIC Educational Resources Information Center

    Helisek, Harriet; Pratt, Donald

    1994-01-01

    Presents a project in which students monitor their use of trash, input and analyze information via a database and computerized graphs, and "reconstruct" extinct or endangered animals from recyclable materials. The activity was done with second-grade students over a period of three to four weeks. (PR)

  13. ACL reconstruction - discharge

    MedlinePlus

    Anterior cruciate ligament reconstruction - discharge; ACL reconstruction - discharge ... had surgery to reconstruct your anterior cruciate ligament (ACL). The surgeon drilled holes in the bones of ...

  14. Successful Reconstruction of Nerve Defects Using Distraction Neurogenesis with a New Experimental Device

    PubMed Central

    Yousef, Mohamed Abdelhamid Ali; Dionigi, Paolo; Marconi, Stefania; Calligaro, Alberto; Cornaglia, Antonia Icaro; Alfonsi, Enrico; Auricchio, Ferdinando

    2015-01-01

    Introduction: Repair of peripheral nerve injuries is an intensive area of challenge and research in modern reconstructive microsurgery. Intensive research is being carried out to develop effective alternatives to the standard nerve autografting, avoiding its drawbacks. The aim of the study was to evaluate the effectiveness of a newly designed mechanical device for the reconstruction of the sciatic nerve in rats in comparison to nerve autografting and to assess the pain during the period of distraction neurogenesis. Methods: Fourteen Sprague Dawley rats were used and randomly assigned into 2 groups with 7 rats in each group; group A (Nerve Autografting group) in which a 10-mm segment of the sciatic nerve was resected and rotated 180 degrees, then primary end-to-end neurorrhaphy was performed in the reverse direction; group B (Nerve Lengthening group) in which the mechanical device was inserted after surgical resection of 10 mm of the sciatic nerve, then secondary end-to-end neurorrhaphy was performed after completing the nerve lengthening. Thirteen weeks later, assessment of the functional sciatic nerve recovery using static sciatic index (SSI) was performed. Furthermore, fourteen weeks after the nerve resection, assessment of the nerve regeneration with electrophysiological study and histological analysis were performed. Also, gastrocnemius wet weight was measured. For pain assessment in group B, Rat Grimace Scale (RGS) score was used. Results: Significantly better functional recovery rate (using the SSI) was reported in the nerve lengthening group in comparison to autografting group. Also, a statistically significant higher nerve conduction velocity was detected in the nerve lengthening group. On histological analysis of the distal nerve section at 3 mm distal to the nerve repair site, significant myelin sheath thickness was detected in the nerve lengthening group. Discussion: Distraction neurogenesis with the new experimental device is a reliable therapeutic

  15. Reconstruction of portal vein and superior mesenteric vein after extensive resection for pancreatic cancer

    PubMed Central

    Kim, Suh Min; Park, Daedo; Min, Sang-Il; Jang, Jin-Young; Kim, Sun-Whe; Ha, Jongwon; Kim, Sang Joon

    2013-01-01

    Purpose Tumor invasion to the portal vein (PV) or superior mesenteric vein (SMV) can be encountered during the surgery for pancreatic cancer. Venous reconstruction is required, but the optimal surgical methods and conduits remain in controversies. Methods From January 2007 to July 2012, 16 venous reconstructions were performed during surgery for pancreatic cancer in 14 patients. We analyzed the methods, conduits, graft patency, and patient survival. Results The involved veins were 14 SMVs and 2 PVs. The operative methods included resection and end-to-end anastomosis in 7 patients, wedge resection with venoplasty in 2 patients, bovine patch repair in 3 patients, and interposition graft with bovine patch in 1 patient. In one patient with a failed interposition graft with great saphenous vein (GSV), the SMV was reconstructed with a prosthetic interposition graft, which was revised with a spiral graft of GSV. Vascular morbidity occurred in 4 cases; occlusion of an interposition graft with GSV or polytetrafluoroethylene, segmental thrombosis and stenosis of the SMV after end-to-end anastomosis. Patency was maintained in patients with bovine patch angioplasty and spiral vein grafts. With mean follow-up of 9.8 months, the 6- and 12-month death-censored graft survival rates were both 81.3%. Conclusion Many of the involved vein segments were repaired primarily. When tension-free anastomosis is impossible, the spiral grafts with GSV or bovine patch grafts are good options to overcome the size mismatch between autologous vein graft and portomesenteric veins. Further follow-up of these patients is needed to demonstrate long-term patency. PMID:23741692

  16. Update on ORNL TRANSFORM Tool: Simulating Multi-Module Advanced Reactor with End-to-End I&C

    SciTech Connect

    Hale, Richard Edward; Fugate, David L.; Cetiner, Sacit M.; Qualls, A. L.

    2015-05-01

    The Small Modular Reactor (SMR) Dynamic System Modeling Tool project is in the fourth year of development. The project is designed to support collaborative modeling and study of various advanced SMR (non-light water cooled reactor) concepts, including the use of multiple coupled reactors at a single site. The focus of this report is the development of a steam generator and drum system model that includes the complex dynamics of typical steam drum systems, the development of instrumentation and controls for the steam generator with drum system model, and the development of multi-reactor module models that reflect the full power reactor innovative small module design concept. The objective of the project is to provide a common simulation environment and baseline modeling resources to facilitate rapid development of dynamic advanced reactor models; ensure consistency among research products within the Instrumentation, Controls, and Human-Machine Interface technical area; and leverage cross-cutting capabilities while minimizing duplication of effort. The combined simulation environment and suite of models are identified as the TRANSFORM tool. The critical elements of this effort include (1) defining a standardized, common simulation environment that can be applied throughout the Advanced Reactors Technology program; (2) developing a library of baseline component modules that can be assembled into full plant models using available geometry, design, and thermal-hydraulic data; (3) defining modeling conventions for interconnecting component models; and (4) establishing user interfaces and support tools to facilitate simulation development (i.e., configuration and parameterization), execution, and results display and capture.

  17. ORNL IntelligentFreight Initiative:Enhanced End-to-End Supply Chain Visibility of Security Sensitive Hazardous Materials

    SciTech Connect

    Walker, Randy M.; Shankar, Mallikarjun; Gorman, Bryan L.

    2009-01-01

    In the post September 11, 2001 (9/11) world the federal government has increased its focus on the manufacturing, distributing, warehousing, and transporting of hazardous materials. In 2002, Congress mandated that the Transportation Security Agency (TSA) designate a subset of hazardous materials that could pose a threat to the American public when transported in sufficiently large quantities. This subset of hazardous materials, which could be weaponized or subjected to a nefarious terrorist act, was designated as Security Sensitive Hazardous Materials (SSHM). Radioactive materials (RAM) were of special concern because actionable intelligence had revealed that Al Qaeda desired to develop a homemade nuclear device or a dirty bomb to use against the United States (US) or its allies.1 Because of this clear and present danger, it is today a national priority to develop and deploy technologies that will provide for visibility and real-time exception notification of SSHM and Radioactive Materials in Quantities of Concern (RAMQC) in international commerce. Over the past eight years Oak Ridge National Laboratory (ORNL) has been developing, implementing, and deploying sensor-based technologies to enhance supply chain visibility. ORNL s research into creating a model for shipments, known as IntelligentFreight, has investigated sensors and sensor integration methods at numerous testbeds throughout the national supply chain. As a result of our research, ORNL believes that most of the information needed by supply chain partners to provide shipment visibility and exceptions-based reporting already exists but is trapped in numerous proprietary or agency-centric databases.

  18. End-to-end 9-D polarized bunch transport in eRHIC energy-recovery recirculator, some aspects

    SciTech Connect

    Meot, F.; Meot, F.; Brooks, S.; Ptitsyn, V.; Trbojevic, D.; Tsoupas, N.

    2015-05-03

    This paper is a brief overview of some of the numerous beam and spin dynamics investigations undertaken in the framework of the design of the FFAG based electron energy recovery re-circulator ring of the eRHIC electron-ion collider project

  19. Caching of a chameleon segment facilitates folding of a protein with end-to-end beta-sheet.

    PubMed

    Mohanty, Sandipan; Hansmann, Ulrich H E

    2008-11-27

    We report results from all-atom simulations of a 49-residue C-terminal fragment of TOP7 in implicit solvent. Using parallel tempering simulations with high statistics, we probe the thermodynamic properties of the protein over a large range of temperatures and evaluate its free energy landscape at room temperature. Our results confirm that the protein folds by a caching mechanism that relies on a chameleon segment. This mechanism differs from the one seen in high-temperature unfolding simulations. Finally, we discuss a possible mechanism for dimerization of the protein. PMID:18956901

  20. Portable air quality sensor unit for participatory monitoring: an end-to-end VESNA-AQ based prototype

    NASA Astrophysics Data System (ADS)

    Vucnik, Matevz; Robinson, Johanna; Smolnikar, Miha; Kocman, David; Horvat, Milena; Mohorcic, Mihael

    2015-04-01

    Key words: portable air quality sensor, CITI-SENSE, participatory monitoring, VESNA-AQ The emergence of low-cost easy to use portable air quality sensors units is opening new possibilities for individuals to assess their exposure to air pollutants at specific place and time, and share this information through the Internet connection. Such portable sensors units are being used in an ongoing citizen science project called CITI-SENSE, which enables citizens to measure and share the data. The project aims through creating citizens observatories' to empower citizens to contribute to and participate in environmental governance, enabling them to support and influence community and societal priorities as well as associated decision making. An air quality measurement system based on VESNA sensor platform was primarily designed within the project for the use as portable sensor unit in selected pilot cities (Belgrade, Ljubljana and Vienna) for monitoring outdoor exposure to pollutants. However, functionally the same unit with different set of sensors could be used for example as an indoor platform. The version designed for the pilot studies was equipped with the following sensors: NO2, O3, CO, temperature, relative humidity, pressure and accelerometer. The personal sensor unit is battery powered and housed in a plastic box. The VESNA-based air quality (AQ) monitoring system comprises the VESNA-AQ portable sensor unit, a smartphone app and the remote server. Personal sensor unit supports wireless connection to an Android smartphone via built-in Wi-Fi. The smartphone in turn serves also as the communication gateway towards the remote server using any of available data connections. Besides the gateway functionality the role of smartphone is to enrich data coming from the personal sensor unit with the GPS location, timestamps and user defined context. This, together with an accelerometer, enables the user to better estimate ones exposure in relation to physical activities, time and location. The end user can monitor the measured parameters through a smartphone application. The smartphone app implements a custom developed LCSP (Lightweight Client Server Protocol) protocol which is used to send requests to the VESNA-AQ unit and to exchange information. When the data is obtained from the VESNA-AQ unit, the mobile application visualizes the data. It also has an option to forward the data to the remote server in a custom JSON structure over a HTTP POST request. The server stores the data in the database and in parallel translates the data to WFS and forwards it to the main CITI-SENSE platform over WFS-T in a common XML format over HTTP POST request. From there data can be accessed through the Internet and visualised in different forms and web applications developed by the CITI-SENSE project. In the course of the project, the collected data will be made publicly available enabling the citizens to participate in environmental governance. Acknowledgements: CITI-SENSE is a Collaborative Project partly funded by the EU FP7-ENV-2012 under grant agreement no 308524 (www.citi-sense.eu).

  1. Scalability Analysis and Use of Compression at the Goddard DAAC and End-to-End MODIS Transfers

    NASA Technical Reports Server (NTRS)

    Menasce, Daniel A.

    1998-01-01

    The goal of this task is to analyze the performance of single and multiple FTP transfer between SCF's and the Goddard DAAC. We developed an analytic model to compute the performance of FTP sessions as a function of various key parameters, implemented the model as a program called FTP Analyzer, and carried out validations with real data obtained by running single and multiple FTP transfer between GSFC and the Miami SCF. The input parameters to the model include the mix to FTP sessions (scenario), and for each FTP session, the file size. The network parameters include the round trip time, packet loss rate, the limiting bandwidth of the network connecting the SCF to a DAAC, TCP's basic timeout, TCP's Maximum Segment Size, and TCP's Maximum Receiver's Window Size. The modeling approach used consisted of modeling TCP's overall throughput, computing TCP's delay per FTP transfer, and then solving a queuing network model that includes the FTP clients and servers.

  2. Parameterizations of truncated food web models from the perspective of an end-to-end model approach

    NASA Astrophysics Data System (ADS)

    Fennel, Wolfgang

    2009-02-01

    Modeling of marine ecosystems is broadly divided into two branches: biogeochemical processes and fish production. The biogeochemical models see the fish only implicitly by mortality rates, while fish production models see the lower food web basically through prescribed food, e.g., copepod biomass. The skill assessment of ecological models, which are usually truncated biogeochemical models, also involves the question of how the effects of the missing higher food web are parameterized. This paper contributes to the goal of bridging biogeochemical models and fish-production models by employing a recently developed coupled NPZDF-model, Fennel [Fennel, W., 2007. Towards bridging biogeochemical and fish production models. Journal of Marine Systems, doi:10.1016/j.jmarsys.2007.06.008]. Here we study parameterizations of truncated NPZD-models from the viewpoint of a complete model. The effects of the higher food web on the cycling of the state variables in a truncated NPZD-model cannot be unambiguously imitated. For example, one can mimic effects of fishery by export fluxes of one of the state variables. It is shown that the mass fluxes between the lower and upper part of the full model food web are significantly smaller than the fluxes within the NPZD-model. However, over longer time scales, relatively small changes can accumulate and eventually become important.

  3. End-to-end remote sensing at the Science and Technology Laboratory of John C. Stennis Space Center

    NASA Technical Reports Server (NTRS)

    Kelly, Patrick; Rickman, Douglas; Smith, Eric

    1991-01-01

    The Science and Technology Laboratory (STL) of Stennis Space Center (SSC) was developing an expertise in remote sensing for more than a decade. Capabilities at SSC/STL include all major areas of the field. STL includes the Sensor Development Laboratory (SDL), Image Processing Center, a Learjet 23 flight platform, and on-staff scientific investigators.

  4. SPAN: A Network Providing Integrated, End-to-End, Sensor-to-Database Solutions for Environmental Sciences

    NASA Astrophysics Data System (ADS)

    Benzel, T.; Cho, Y. H.; Deschon, A.; Gullapalli, S.; Silva, F.

    2009-12-01

    In recent years, advances in sensor network technology have shown great promise to revolutionize environmental data collection. Still, wide spread adoption of these systems by domain experts has been lacking, and these have remained the purview of the engineers who design them. While there are many data logging options for basic data collection in the field currently, scientists are often required to visit the deployment sites to retrieve their data and manually import it into spreadsheets. Some advanced commercial software systems do allow scientists to collect data remotely, but most of these systems only allow point-to-point access, and require proprietary hardware. Furthermore, these commercial solutions preclude the use of sensors from other manufacturers or integration with internet based database repositories and compute engines. Therefore, scientists often must download and manually reformat their data before uploading it to the repositories if they wish to share their data. We present an open-source, low-cost, extensible, turnkey solution called Sensor Processing and Acquisition Network (SPAN) which provides a robust and flexible sensor network service. At the deployment site, SPAN leverages low-power generic embedded processors to integrate variety of commercially available sensor hardware to the network of environmental observation systems. By bringing intelligence close to the sensed phenomena, we can remotely control configuration and re-use, establish rules to trigger sensor activity, manage power requirements, and control the two-way flow of sensed data as well as control information to the sensors. Key features of our design include (1) adoption of a hardware agnostic architecture: our solutions are compatible with several programmable platforms, sensor systems, communication devices and protocols. (2) information standardization: our system supports several popular communication protocols and data formats, and (3) extensible data support: our system works with several existing data storage systems, data models and web based services as needed by the domain experts; examples include standard MySQL databases, Sensorbase (from UCLA), as well as SPAN Cloud, a system built using Google's Application Engine that allows scientists to use Google's cloud computing cyber-infrastructure. We provide a simple, yet flexible data access control mechanism that allows groups of researchers to share their data in SPAN Cloud. In this talk, we will describe the SPAN architecture, its components, our development plans, our vision for the future and results from current deployments that continue to drive the design of our system.

  5. The NOAO Data Products Program: Developing an End-to-End Data Management System in Support of the Virtual Observatory

    NASA Astrophysics Data System (ADS)

    Smith, R. C.; Boroson, T.; Seaman, R.

    2007-10-01

    The NOAO Data Products Program (DPP) is responsible for the development and operation of the data management system for NOAO and affiliated observatories, and for the scientific support of users accessing our data holdings and using our tools and services. At the core of this mission is the capture of data from instruments at these observatories and the delivery of that content to both the Principle Investigators (PIs) who proposed for the observations and, after an appropriate proprietary period, to users worldwide who are interested in using the data for their own (often very different) scientific projects. However, delivery of raw and/or reduced images to users only scratches the surface of the extensive potential which the international Virtual Observatory (VO) initiative has to offer. By designing the whole NOAO/DPP program around not only VO standards, but more importantly around VO principles, the program becomes not an exercise in data management and NOAO user support, but rather a VO-centric program which serves the growing world-wide VO community. It is this more global aspect that drives NOAO/DPP planning, as well as more specifically the design, development, and operations of the various components of our system. In the following sections we discuss these components and how they work together to form our VO-centric program.

  6. An integrated healthcare information system for end-to-end standardized exchange and homogeneous management of digital ECG formats.

    PubMed

    Trigo, Jesús Daniel; Martínez, Ignacio; Alesanco, Alvaro; Kollmann, Alexander; Escayola, Javier; Hayn, Dieter; Schreier, Günter; García, José

    2012-07-01

    This paper investigates the application of the enterprise information system (EIS) paradigm to standardized cardiovascular condition monitoring. There are many specifications in cardiology, particularly in the ECG standardization arena. The existence of ECG formats, however, does not guarantee the implementation of homogeneous, standardized solutions for ECG management. In fact, hospital management services need to cope with various ECG formats and, moreover, several different visualization applications. This heterogeneity hampers the normalization of integrated, standardized healthcare information systems, hence the need for finding an appropriate combination of ECG formats and a suitable EIS-based software architecture that enables standardized exchange and homogeneous management of ECG formats. Determining such a combination is one objective of this paper. The second aim is to design and develop the integrated healthcare information system that satisfies the requirements posed by the previous determination. The ECG formats selected include ISO/IEEE11073, Standard Communications Protocol for Computer-Assisted Electrocardiography, and an ECG ontology. The EIS-enabling techniques and technologies selected include web services, simple object access protocol, extensible markup language, or business process execution language. Such a selection ensures the standardized exchange of ECGs within, or across, healthcare information systems while providing modularity and accessibility. PMID:22453644

  7. Towards a Software Framework to Support Deployment of Low Cost End-to-End Hydroclimatological Sensor Network

    NASA Astrophysics Data System (ADS)

    Celicourt, P.; Piasecki, M.

    2015-12-01

    Deployment of environmental sensors assemblies based on cheap platforms such as Raspberry Pi and Arduino have gained much attention over the past few years. While they are more attractive due to their ability to be controlled with a few programming language choices, the configuration task can become quite complex due to the need of having to learn several different proprietary data formats and protocols which constitute a bottleneck for the expansion of sensor network. In response to this rising complexity the Institute of Electrical and Electronics Engineers (IEEE) has sponsored the development of the IEEE 1451 standard in an attempt to introduce a common standard. The most innovative concept of the standard is the Transducer Electronic Data Sheet (TEDS) which enables transducers to self-identify, self-describe, self-calibrate, to exhibit plug-and-play functionality, etc. We used Python to develop an IEEE 1451.0 platform-independent graphical user interface to generate and provide sufficient information about almost ANY sensor and sensor platforms for sensor programming purposes, automatic calibration of sensors data, incorporation of back-end demands on data management in TEDS for automatic standard-based data storage, search and discovery purposes. These features are paramount to make data management much less onerous in large scale sensor network. Along with the TEDS Creator, we developed a tool namely HydroUnits for three specific purposes: encoding of physical units in the TEDS, dimensional analysis, and on-the-fly conversion of time series allowing users to retrieve data in a desired equivalent unit while accommodating unforeseen and user-defined units. In addition, our back-end data management comprises the Python/Django equivalent of the CUAHSI Observations Data Model (ODM) namely DjangODM that will be hosted by a MongoDB Database Server which offers more convenience for our application. We are also developing a data which will be paired with the data autoloading capability of Django and a TEDS processing script to populate the database with the incoming data. The Python WaterOneFlow Web Services developed by the Texas Water Development Board will be used to publish the data. The software suite is being tested on the Raspberry Pi as end node and a laptop PC as the base station in a wireless setting.

  8. SU-E-T-268: Proton Radiosurgery End-To-End Testing Using Lucy 3D QA Phantom

    SciTech Connect

    Choi, D; Gordon, I; Ghebremedhin, A; Wroe, A; Schulte, R; Bush, D; Slater, J; Patyal, B

    2014-06-01

    Purpose: To check the overall accuracy of proton radiosurgery treatment delivery using ready-made circular collimator inserts and fixed thickness compensating boluses. Methods: Lucy 3D QA phantom (Standard Imaging Inc. WI, USA) inserted with GaFchromicTM film was irradiated with laterally scattered and longitudinally spread-out 126.8 MeV proton beams. The tests followed every step in the proton radiosurgery treatment delivery process: CT scan (GE Lightspeed VCT), target contouring, treatment planning (Odyssey 5.0, Optivus, CA), portal calibration, target localization using robotic couch with image guidance and dose delivery at planned gantry angles. A 2 cm diameter collimator insert in a 4 cm diameter radiosurgery cone and a 1.2 cm thick compensating flat bolus were used for all beams. Film dosimetry (RIT114 v5.0, Radiological Imaging Technology, CO, USA) was used to evaluate the accuracy of target localization and relative dose distributions compared to those calculated by the treatment planning system. Results: The localization accuracy was estimated by analyzing the GaFchromic films irradiated at gantry 0, 90 and 270 degrees. We observed 0.5 mm shift in lateral direction (patient left), ±0.9 mm shift in AP direction and ±1.0 mm shift in vertical direction (gantry dependent). The isodose overlays showed good agreement (<2mm, 50% isodose lines) between measured and calculated doses. Conclusion: Localization accuracy depends on gantry sag, CT resolution and distortion, DRRs from treatment planning computer, localization accuracy of image guidance system, fabrication of ready-made aperture and cone housing. The total deviation from the isocenter was 1.4 mm. Dose distribution uncertainty comes from distal end error due to bolus and CT density, in addition to localization error. The planned dose distribution was well matched (>90%) to the measured values 2%/2mm criteria. Our test showed the robustness of our proton radiosurgery treatment delivery system using ready-made collimator inserts and fixed thickness compensating boluses.

  9. Breast Reconstruction After Mastectomy

    MedlinePlus

    ... around the cancer removed (lumpectomy or breast-conserving surgery) might not need reconstruction, but sometimes they do. Breast reconstruction is done by a plastic surgeon. Should I have breast reconstruction? Breast reconstruction ...

  10. Wavefront Reconstruction for a Natural Guide Star Ground Layer Adaptive Optics System on the Giant Magellan Telescope

    NASA Astrophysics Data System (ADS)

    Van Dam, Marcos; Bouchez, Antonin; Conan, Rodolphe; McLeod, Brian

    2013-12-01

    In this paper, we present a wavefront reconstruction paradigm for NGS GLAO systems. The conventional approach to reconstructing the wavefront for LGS GLAO systems is to have a number of LGSs in a ring outside the science field and simply average the individual wavefronts. This approach is not well-suited to NGS GLAO because the stars have an irregular distribution and varying magnitudes. In this paper, we derive covariance matrices for the wavefronts in different directions and the measurement noise. Using these covariance matrices, we are able to find the minimum-variance reconstructor and estimate the residual wavefront as a function of location in the field. This can be used to determine which guide stars produce the best correction. End-to-end simulations in YAO are run to estimate the expected performance of the NGS GLAO system for the Giant Magellan Telescope. We find that there is essentially full sky coverage.

  11. Integration of real-time 3D capture, reconstruction, and light-field display

    NASA Astrophysics Data System (ADS)

    Zhang, Zhaoxing; Geng, Zheng; Li, Tuotuo; Pei, Renjing; Liu, Yongchun; Zhang, Xiao

    2015-03-01

    Effective integration of 3D acquisition, reconstruction (modeling) and display technologies into a seamless systems provides augmented experience of visualizing and analyzing real objects and scenes with realistic 3D sensation. Applications can be found in medical imaging, gaming, virtual or augmented reality and hybrid simulations. Although 3D acquisition, reconstruction, and display technologies have gained significant momentum in recent years, there seems a lack of attention on synergistically combining these components into a "end-to-end" 3D visualization system. We designed, built and tested an integrated 3D visualization system that is able to capture in real-time 3D light-field images, perform 3D reconstruction to build 3D model of the objects, and display the 3D model on a large autostereoscopic screen. In this article, we will present our system architecture and component designs, hardware/software implementations, and experimental results. We will elaborate on our recent progress on sparse camera array light-field 3D acquisition, real-time dense 3D reconstruction, and autostereoscopic multi-view 3D display. A prototype is finally presented with test results to illustrate the effectiveness of our proposed integrated 3D visualization system.

  12. Fission Spectrum

    DOE R&D Accomplishments Database

    Bloch, F.; Staub, H.

    1943-08-18

    Measurements of the spectrum of the fission neutrons of 25 are described, in which the energy of the neutrons is determined from the ionization produced by individual hydrogen recoils. The slow neutrons producing fission are obtained by slowing down the fast neutrons from the Be-D reaction of the Stanford cyclotron. In order to distinguish between fission neutrons and the remaining fast cyclotron neutrons both the cyclotron current and the pusle amplifier are modulated. A hollow neutron container, in which slow neutrons have a lifetime of about 2 milliseconds, avoids the use of large distances. This method results in much higher intensities than the usual modulation arrangement. The results show a continuous distribution of neutrons with a rather wide maximum at about 0.8 MV falling off to half of its maximum value at 2.0 MV. The total number of netrons is determined by comparison with the number of fission fragments. The result seems to indicate that only about 30% of the neutrons have energies below .8 MV. Various tests are described which were performed in order to rule out modification of the spectrum by inelastic scattering. Decl. May 4, 1951

  13. Reconstruction of the anterior cruciate ligament.

    PubMed

    Seedhom, B B

    1992-01-01

    Ligaments are strong collagenous structures that act as constraints on joint motion, thus confining the articular surfaces to more or less the same paths. In so doing they prevent arbitrary apposition of these surfaces from occurring and resulting in abnormal stresses which may damage the joint surfaces. Ligaments rupture due to excessive loads, particularly those resulting from trauma occurring during sporting events or motor vehicle accidents. Knee and ankle joints have the highest frequency of ligamentous injuries. This paper is a brief review of the current approaches to the reconstruction of the knee ligaments with specific reference to the anterior cruciate ligament (ACL) being the most frequently reconstructed. This is not only because it is frequently injured but also because of the debilitating consequences of such an injury. Approaches ranging from the conservative to those that advocate the use of frank prosthetic replacement have been adopted by surgeons at both ends of the spectrum. Following a discussion of the rationale for reconstruction of the ACL, the mechanical and biological considerations of the reconstructive procedure are discussed. The different methods of ACL reconstruction are reviewed. These include: (a) primary repair, (b) reconstruction with different tissues, including autogenous allografts and xenografts, (c) reconstruction employing different synthetic devices. A brief discussion of the procedures used for reconstruction with different types of tissue and of the surviving examples of the synthetic devices will follow. PMID:1418190

  14. Transsplenic portal vein reconstruction-transjugular intrahepatic portosystemic shunt in a patient with portal and splenic vein thrombosis.

    PubMed

    Salsamendi, Jason T; Gortes, Francisco J; Shnayder, Michelle; Doshi, Mehul H; Fan, Ji; Narayanan, Govindarajan

    2016-09-01

    Portal vein thrombosis (PVT) is a potential complication of cirrhosis and can worsen outcomes after liver transplant (LT). Portal vein reconstruction-transjugular intrahepatic portosystemic shunt (PVR-TIPS) can restore flow through the portal vein (PV) and facilitate LT by avoiding complex vascular conduits. We present a case of transsplenic PVR-TIPS in the setting of complete PVT and splenic vein (SV) thrombosis. The patient had a 3-year history of PVT complicated by abdominal pain, ascites, and paraesophageal varices. A SV tributary provided access to the main SV and was punctured percutaneously under ultrasound scan guidance. PV access, PV and SV venoplasty, and TIPS placement were successfully performed without complex techniques. The patient underwent LT with successful end-to-end anastomosis of the PVs. Our case suggests transsplenic PVR-TIPS to be a safe and effective alternative to conventional PVR-TIPS in patients with PVT and SV thrombosis. PMID:27594947

  15. Neuromagnetic source reconstruction

    SciTech Connect

    Lewis, P.S.; Mosher, J.C.; Leahy, R.M.

    1994-12-31

    In neuromagnetic source reconstruction, a functional map of neural activity is constructed from noninvasive magnetoencephalographic (MEG) measurements. The overall reconstruction problem is under-determined, so some form of source modeling must be applied. We review the two main classes of reconstruction techniques-parametric current dipole models and nonparametric distributed source reconstructions. Current dipole reconstructions use a physically plausible source model, but are limited to cases in which the neural currents are expected to be highly sparse and localized. Distributed source reconstructions can be applied to a wider variety of cases, but must incorporate an implicit source, model in order to arrive at a single reconstruction. We examine distributed source reconstruction in a Bayesian framework to highlight the implicit nonphysical Gaussian assumptions of minimum norm based reconstruction algorithms. We conclude with a brief discussion of alternative non-Gaussian approachs.

  16. Autism Spectrum Disorder

    MedlinePlus

    ... Awards Enhancing Diversity Find People About NINDS NINDS Autism Spectrum Disorder Information Page Condensed from Autism Spectrum ... en Español Additional resources from MedlinePlus What is Autism Spectrum Disorder? Autistic disorder (sometimes called autism or ...

  17. Breast Reconstruction after Mastectomy

    PubMed Central

    Schmauss, Daniel; Machens, Hans-Günther; Harder, Yves

    2016-01-01

    Breast cancer is the leading cause of cancer death in women worldwide. Its surgical approach has become less and less mutilating in the last decades. However, the overall number of breast reconstructions has significantly increased lately. Nowadays, breast reconstruction should be individualized at its best, first of all taking into consideration not only the oncological aspects of the tumor, neo-/adjuvant treatment, and genetic predisposition, but also its timing (immediate versus delayed breast reconstruction), as well as the patient’s condition and wish. This article gives an overview over the various possibilities of breast reconstruction, including implant- and expander-based reconstruction, flap-based reconstruction (vascularized autologous tissue), the combination of implant and flap, reconstruction using non-vascularized autologous fat, as well as refinement surgery after breast reconstruction. PMID:26835456

  18. Head and face reconstruction

    MedlinePlus

    Head and face reconstruction is surgery to repair or reshape deformities of the head and face (craniofacial). ... How surgery for head and face deformities (craniofacial reconstruction) ... and the person's condition. Surgical repairs involve the ...

  19. Head and face reconstruction

    MedlinePlus

    ... Birth defects and deformities from conditions such as cleft lip or palate , craniosynostosis , Apert syndrome Deformities caused by ... Orbital-craniofacial surgery; Facial reconstruction Images Skull Skull Cleft lip repair - series Craniofacial reconstruction - series References Baker SR. ...

  20. Methods of Voice Reconstruction

    PubMed Central

    Chen, Hung-Chi; Kim Evans, Karen F.; Salgado, Christopher J.; Mardini, Samir

    2010-01-01

    This article reviews methods of voice reconstruction. Nonsurgical methods of voice reconstruction include electrolarynx, pneumatic artificial larynx, and esophageal speech. Surgical methods of voice reconstruction include neoglottis, tracheoesophageal puncture, and prosthesis. Tracheoesophageal puncture can be performed in patients with pedicled flaps such as colon interposition, jejunum, or gastric pull-up or in free flaps such as perforator flaps, jejunum, and colon flaps. Other flaps for voice reconstruction include the ileocolon flap and jejunum. Laryngeal transplantation is also reviewed. PMID:22550443

  1. Reoperative midface reconstruction.

    PubMed

    Acero, Julio; García, Eloy

    2011-02-01

    Reoperative reconstruction of the midface is a challenging issue because of the complexity of this region and the severity of the aesthetic and functional sequela related to the absence or failure of a primary reconstruction. The different situations that can lead to the indication of a reoperative reconstructive procedure after previous oncologic ablative procedures in the midface are reviewed. Surgical techniques, anatomic problems, and limitations affecting the reoperative reconstruction in this region of the head and neck are discussed. PMID:21126882

  2. Autologous Microvascular Breast Reconstruction

    PubMed Central

    Ramakrishnan, Venkat

    2013-01-01

    Autologous microvascular breast reconstruction is widely accepted as a key component of breast cancer treatment. There are two basic donor sites; the anterior abdominal wall and the thigh/buttock region. Each of these regions provides for a number of flaps that are successfully utilised in breast reconstruction. Refinement of surgical technique and the drive towards minimising donor site morbidity whilst maximising flap vascularity in breast reconstruction has seen an evolution towards perforator based flap reconstructions, however myocutaneous flaps are still commonly practiced. We review herein the current methods of autologous microvascular breast reconstruction. PMID:23362474

  3. Performances of JEM-EUSO: angular reconstruction. The JEM-EUSO Collaboration

    NASA Astrophysics Data System (ADS)

    Adams, J. H.; Ahmad, S.; Albert, J.-N.; Allard, D.; Anchordoqui, L.; Andreev, V.; Anzalone, A.; Arai, Y.; Asano, K.; Ave Pernas, M.; Baragatti, P.; Barrillon, P.; Batsch, T.; Bayer, J.; Bechini, R.; Belenguer, T.; Bellotti, R.; Belov, K.; Berlind, A. A.; Bertaina, M.; Biermann, P. L.; Biktemerova, S.; Blaksley, C.; Blanc, N.; Błȩcki, J.; Blin-Bondil, S.; Blümer, J.; Bobik, P.; Bogomilov, M.; Bonamente, M.; Briggs, M. S.; Briz, S.; Bruno, A.; Cafagna, F.; Campana, D.; Capdevielle, J.-N.; Caruso, R.; Casolino, M.; Cassardo, C.; Castellinic, G.; Catalano, C.; Catalano, G.; Cellino, A.; Chikawa, M.; Christl, M. J.; Cline, D.; Connaughton, V.; Conti, L.; Cordero, G.; Crawford, H. J.; Cremonini, R.; Csorna, S.; Dagoret-Campagne, S.; de Castro, A. J.; De Donato, C.; de la Taille, C.; De Santis, C.; del Peral, L.; Dell'Oro, A.; De Simone, N.; Di Martino, M.; Distratis, G.; Dulucq, F.; Dupieux, M.; Ebersoldt, A.; Ebisuzaki, T.; Engel, R.; Falk, S.; Fang, K.; Fenu, F.; Fernández-Gómez, I.; Ferrarese, S.; Finco, D.; Flamini, M.; Fornaro, C.; Franceschi, A.; Fujimoto, J.; Fukushima, M.; Galeotti, P.; Garipov, G.; Geary, J.; Gelmini, G.; Giraudo, G.; Gonchar, M.; González Alvarado, C.; Gorodetzky, P.; Guarino, F.; Guzmán, A.; Hachisu, Y.; Harlov, B.; Haungs, A.; Hernández Carretero, J.; Higashide, K.; Ikeda, D.; Ikeda, H.; Inoue, N.; Inoue, S.; Insolia, A.; Isgrò, F.; Itow, Y.; Joven, E.; Judd, E. G.; Jung, A.; Kajino, F.; Kajino, T.; Kaneko, I.; Karadzhov, Y.; Karczmarczyk, J.; Karus, M.; Katahira, K.; Kawai, K.; Kawasaki, Y.; Keilhauer, B.; Khrenov, B. A.; Kim, J.-S.; Kim, S.-W.; Kim, S.-W.; Kleifges, M.; Klimov, P. A.; Kolev, D.; Kreykenbohm, I.; Kudela, K.; Kurihara, Y.; Kusenko, A.; Kuznetsov, E.; Lacombe, M.; Lachaud, C.; Lee, J.; Licandro, J.; Lim, H.; López, F.; Maccarone, M. C.; Mannheim, K.; Maravilla, D.; Marcelli, L.; Marini, A.; Martinez, O.; Masciantonio, G.; Mase, K.; Matev, R.; Medina-Tanco, G.; Mernik, T.; Miyamoto, H.; Miyazaki, Y.; Mizumoto, Y.; Modestino, G.; Monaco, A.; Monnier-Ragaigne, D.; Morales de los Ríos, J. A.; Moretto, C.; Morozenko, V. S.; Mot, B.; Murakami, T.; Murakami, M. Nagano; Nagata, M.; Nagataki, S.; Nakamura, T.; Napolitano, T.; Naumov, D.; Nava, R.; Neronov, A.; Nomoto, K.; Nonaka, T.; Ogawa, T.; Ogio, S.; Ohmori, H.; Olinto, A. V.; Orleański, P.; Osteria, G.; Panasyuk, M. I.; Parizot, E.; Park, I. H.; Park, H. W.; Pastircak, B.; Patzak, T.; Paul, T.; Pennypacker, C.; Perez Cano, S.; Peter, T.; Picozza, P.; Pierog, T.; Piotrowski, L. W.; Piraino, S.; Plebaniak, Z.; Pollini, A.; Prat, P.; Prévôt, G.; Prieto, H.; Putis, M.; Reardon, P.; Reyes, M.; Ricci, M.; Rodríguez, I.; Rodríguez Frías, M. D.; Ronga, F.; Roth, M.; Rothkaehl, H.; Roudil, G.; Rusinov, I.; Rybczyński, M.; Sabau, M. D.; Sáez-Cano, G.; Sagawa, H.; Saito, A.; Sakaki, N.; Sakata, M.; Salazar, H.; Sánchez, S.; Santangelo, A.; Santiago Crúz, L.; Sanz Palomino, M.; Saprykin, O.; Sarazin, F.; Sato, H.; Sato, M.; Schanz, T.; Schieler, H.; Scotti, V.; Segreto, A.; Selmane, S.; Semikoz, D.; Serra, M.; Sharakin, S.; Shibata, T.; Shimizu, H. M.; Shinozaki, K.; Shirahama, T.; Siemieniec-Oziȩbło, G.; Silva López, H. H.; Sledd, J.; Słomińska, K.; Sobey, A.; Sugiyama, T.; Supanitsky, D.; Suzuki, M.; Szabelska, B.; Szabelski, J.; Tajima, F.; Tajima, N.; Tajima, T.; Takahashi, Y.; Takami, H.; Takeda, M.; Takizawa, Y.; Tenzer, C.; Tibolla, O.; Tkachev, L.; Tokuno, H.; Tomida, T.; Tone, N.; Toscano, S.; Trillaud, F.; Tsenov, R.; Tsunesada, Y.; Tsuno, K.; Tymieniecka, T.; Uchihori, Y.; Unger, M.; Vaduvescu, O.; Valdés-Galicia, J. F.; Vallania, P.; Valore, L.; Vankova, G.; Vigorito, C.; Villaseñor, L.; von Ballmoos, P.; Wada, S.; Watanabe, J.; Watanabe, S.; Watts, J.; Weber, M.; Weiler, T. J.; Wibig, T.; Wiencke, L.; Wille, M.; Wilms, J.; Włodarczyk, Z.; Yamamoto, T.; Yamamoto, Y.; Yang, J.; Yano, H.; Yashin, I. V.; Yonetoku, D.; Yoshida, K.; Yoshida, S.; Young, R.; Zotov, M. Yu.; Zuccaro Marchi, A.

    2015-11-01

    Mounted on the International Space Station(ISS), the Extreme Universe Space Observatory, on-board the Japanese Experimental Module (JEM-EUSO), relies on the well established fluorescence technique to observe Extensive Air Showers (EAS) developing in the earth's atmosphere. Focusing on the detection of Ultra High Energy Cosmic Rays (UHECR) in the decade of 1020eV, JEM-EUSO will face new challenges by applying this technique from space. The EUSO Simulation and Analysis Framework (ESAF) has been developed in this context to provide a full end-to-end simulation frame, and assess the overall performance of the detector. Within ESAF, angular reconstruction can be separated into two conceptually different steps. The first step is pattern recognition, or filtering, of the signal to separate it from the background. The second step is to perform different types of fitting in order to search for the relevant geometrical parameters that best describe the previously selected signal. In this paper, we discuss some of the techniques we have implemented in ESAF to perform the geometrical reconstruction of EAS seen by JEM-EUSO. We also conduct thorough tests to assess the performances of these techniques in conditions which are relevant to the scope of the JEM-EUSO mission. We conclude by showing the expected angular resolution in the energy range that JEM-EUSO is expected to observe.

  4. Wide-field wavefront sensing in solar adaptive optics : modeling and effects on reconstruction

    NASA Astrophysics Data System (ADS)

    Béchet, Clémentine; Tallon, Michel; Montilla, Icíar; Langlois, Maud

    2013-12-01

    The planned 4-meter diameter of the European Solar Telescope (EST) is aimed at providing high spatial resolution and large photon collecting area, in order to understand in particular the mechanisms of magnetic coupling in the chromosphere and the photosphere. To reach its goals in the visible and the near-infrared, EST is designed with both a conventional and a multi-conjugate adaptive optics (AO) of similar complexity than the ones featured for the Extremely Large Telescopes. In addition, the AO on EST has to face a particularity of solar AO: the wavefront sensing on extended sources with measurement fields of about 10'' in size. Reviewing recent literature together with an independent analysis, we investigate the impact of extended-field sensing in AO for large solar telescopes. Sensing modeling and its effect on reconstruction performance are analyzed, thanks to simulations performed with the Fractal Iterative Method for tomography (FRiM-3D), showing the difficulty to correct high altitude turbulence. We introduce a new approximate direct model of extended-source sensing which greatly improves the quality of the end-to-end simulations for EST AO. Next, we try to improve the conventional solar AO correction by using this new model in the reconstruction. Our simulations do not show significant benefits from using such tomographic model in this conventional AO configuration and under typical atmospheric conditions.

  5. [MAX-DOAS Tomography Reconstruction for Gas Plume].

    PubMed

    Wei, Min-hong; Tong, Min-ming; Li, Su-wen; Xiao, Jian-yu

    2015-08-01

    In order to achieve precisely two-dimensional spatial distribution reconstruction of smoke plume, passive MAX-DOAS tomography is established, the measurement of the spatial distribution of the exhaust plume is implemented by more passive multi-axis differential absorption spectrum system. First, the multi-axis differential absorption spectrum system and its mechanism of inverse gas concentration are introduced in the paper. Then, algebra iterative algorithm is adopted to extract the information of the trace gas concentration in reconstruction simulation with different models and different scanning optical path, and the reconstruction program is designed. Then, the numerical simulation results are compared. Finally, a platform of multi-axis differential absorption optical tomography system is set up, a field campaign was carried out. The numerical simulation results show that the MAX-DOAS tomography can accurately reconstruct two-dimensional spatial distribution of plume model, the re- construction error of MAX-DOAS tomography with four light sources is about a third of the reconstruction error with double light sources, moreover, the reconstruction time is about a quarter of the reconstruction time of double light sources, and the reconstruction error of the twin peaks model is greater than that of the one peak model. Field test results show that the integral data of reconstruction image is consistent with the measured projection data of multi-axis differential absorption spectrum, the spatial distribution reconstruction of plume is in line with the actual situation. Studies have shown that the result of numerical simulation and field test results have consistency. PMID:26672304

  6. Three-dimensional holographic reconstruction from computational tomography images

    NASA Astrophysics Data System (ADS)

    Zhao, Yan; Cao, Liangcai; Zhang, Hao; He, Qingsheng; Jin, Guofan

    2014-11-01

    An angular spectrum holographic algorithm is proposed for generating three-dimensional (3D) reconstruction from multiple computational tomography (CT) slices. Objects consist of multiple slices can be easily modeled by the angular spectrum. So the 3D structure can be built through the superposition of computer generated phase holograms originally from parallel discrete planes at different depths. Then the superposed phase hologram is uploaded to the phase-only spatial light modulator (SLM). With the SLM illuminated by the coherent light, the 3D reconstruction is observed by a camera. The proposed method is more computationally efficient compared with the point source algorithm, and the angular spectrum holographic algorithm can process more large-capacity CT data for the 3D visualization. Experiment demonstrates the feasibility of reconstructing CT biological structure with holographic display.

  7. Lower Eyelid Reconstruction.

    PubMed

    Holds, John B

    2016-05-01

    Lower eyelid defects are common, and a systematic approach to reconstruction of the lower eyelid is required. Attention to the bilaminar eyelid anatomy and canthal support structures, with efforts to maintain functionally important structures, such as the lacrimal canalicular system, is vital to appropriate lower eyelid reconstruction. Techniques of advancement and rotation flaps and grafting of skin and mucosa are mainstays of lower eyelid reconstruction. An appropriate armamentarium of techniques allows for optimal surgical results. PMID:27105804

  8. Flexor pulley reconstruction.

    PubMed

    Dy, Christopher J; Daluiski, Aaron

    2013-05-01

    Flexor pulley reconstruction is a challenging surgery. Injuries often occur after traumatic lacerations or forceful extension applied to an acutely flexed finger. Surgical treatment is reserved for patients with multiple closed pulley ruptures, persistent pain, or dysfunction after attempted nonoperative management of a single pulley rupture, or during concurrent or staged flexor tendon repair or reconstruction. If the pulley cannot be repaired primarily, pulley reconstruction can be performed using graft woven into remnant pulley rim or looping graft around the phalanx. Regardless of the reconstructive technique, the surgeon should emulate the length, tension, and glide of the native pulley. PMID:23660059

  9. Head and neck reconstruction

    PubMed Central

    Yadav, Prabha

    2013-01-01

    Whatever is excisable, is reconstructable! “You excise, we will reconstruct” are the confident words of reconstructive surgeons today. Reconstruction with multiple flaps has become routine. Radial artery (FRAF), Antero lateral thigh (ALT) and Fibula osteo cutaneous flap (FFOCF) are three most popular free flaps which can reconstruct any defect with excellent asthetics and performance. Radial Artery provides thin, pliable innervated skin; ALT large amount of skin & bulk; and FFOCF strong 22 to 25 centimetres of bone and reliable skin paddle. Free flap survival has gone to 98% in most of the renouned institutes and is an established escalator in management of defects. PMID:24501464

  10. Autism Spectrum Disorder

    MedlinePlus

    Autism spectrum disorder (ASD) is a neurological and developmental disorder that begins early in childhood and lasts throughout a ... and pervasive developmental disorders. It is called a "spectrum" disorder because people with ASD can have a ...

  11. Autism Spectrum Disorder (ASD)

    MedlinePlus

    ... spectrum disorder (ASD) is a group of developmental disabilities that can cause significant social, communication and behavioral ... for autism spectrum disorder (ASD) and other developmental disabilities. More E-mail Your Friends "Children with autism ...

  12. Attractor reconstruction for non-linear systems: a methodological note

    USGS Publications Warehouse

    Nichols, J.M.; Nichols, J.D.

    2001-01-01

    Attractor reconstruction is an important step in the process of making predictions for non-linear time-series and in the computation of certain invariant quantities used to characterize the dynamics of such series. The utility of computed predictions and invariant quantities is dependent on the accuracy of attractor reconstruction, which in turn is determined by the methods used in the reconstruction process. This paper suggests methods by which the delay and embedding dimension may be selected for a typical delay coordinate reconstruction. A comparison is drawn between the use of the autocorrelation function and mutual information in quantifying the delay. In addition, a false nearest neighbor (FNN) approach is used in minimizing the number of delay vectors needed. Results highlight the need for an accurate reconstruction in the computation of the Lyapunov spectrum and in prediction algorithms.

  13. Education for Reconstruction.

    ERIC Educational Resources Information Center

    Phillips, David; And Others

    This report describes the main questions that various international agencies must address in order to reconstruct education in countries that have experienced crisis. "Crisis" is defined as war, natural disaster, and extreme political and economic upheaval. Many of the problems of educational reconstruction with which the Allies contended in…

  14. Bitzer's Model Reconstructed.

    ERIC Educational Resources Information Center

    Lybarger, Scott; Smith, Craig R.

    1996-01-01

    Reconstructs Lloyd Bitzer's situational model to serve as a guide for the generation of multiperspectival critical assessments of rhetorical discourse. Uses two of President Bush's speeches on the drug crisis to illustrate how the reconstructed model can account for such modern problems as multiple audiences, perceptions, and exigencies. (PA)

  15. Beam hardening correction for sparse-view CT reconstruction

    NASA Astrophysics Data System (ADS)

    Liu, Wenlei; Rong, Junyan; Gao, Peng; Liao, Qimei; Lu, HongBing

    2015-03-01

    Beam hardening, which is caused by spectrum polychromatism of the X-ray beam, may result in various artifacts in the reconstructed image and degrade image quality. The artifacts would be further aggravated for the sparse-view reconstruction due to insufficient sampling data. Considering the advantages of the total-variation (TV) minimization in CT reconstruction with sparse-view data, in this paper, we propose a beam hardening correction method for sparse-view CT reconstruction based on Brabant's modeling. In this correction model for beam hardening, the attenuation coefficient of each voxel at the effective energy is modeled and estimated linearly, and can be applied in an iterative framework, such as simultaneous algebraic reconstruction technique (SART). By integrating the correction model into the forward projector of the algebraic reconstruction technique (ART), the TV minimization can recover images when only a limited number of projections are available. The proposed method does not need prior information about the beam spectrum. Preliminary validation using Monte Carlo simulations indicates that the proposed method can provide better reconstructed images from sparse-view projection data, with effective suppression of artifacts caused by beam hardening. With appropriate modeling of other degrading effects such as photon scattering, the proposed framework may provide a new way for low-dose CT imaging.

  16. The CMS Reconstruction Software

    NASA Astrophysics Data System (ADS)

    Lange, David J.; CMS Collaboration

    2011-12-01

    We report on the status and plans for the event reconstruction software of the CMS experiment. The CMS reconstruction algorithms are the basis for a wide range of data analysis approaches currently under study by the CMS collaboration using the first high-energy run of the LHC. These algorithms have been primarily developed and validated using simulated data samples, and are now being commissioned with LHC proton-proton collision data samples. The CMS reconstruction is now operated routinely on all events triggered by the CMS detector, both in a close to real-time prompt reconstruction processing and in frequent passes over the full recorded CMS data set. We discuss the overall software design, development cycle, computational requirements and performance, recent operational performance, and planned improvements of the CMS reconstruction software.

  17. Quantitative simulation and density reconstruction in high-energy X-ray radiograph

    NASA Astrophysics Data System (ADS)

    Tang, Li; Xu, Haibo

    2014-03-01

    Numerical radiograph using Monte Carlo method is used to study fidelity of density reconstruction in high-energy X-ray radiography. A density reconstruction method for a polyenergetic X-ray source and an object composed of different materials is proposed. The method includes energy spectrum, angular spectrum and spot size of photon source. And it includes mass absorption coefficients explicitly in density reconstruction as well. A constrained conjugate gradient algorithm and variation regularization are applied to determine material edges and density reconstruction of a French test object. It shows that the method is valid for density reconstruction and energy spectrum of imaging photons is important in obtaining accurate material densities in high-energy X-ray radiograph.

  18. 42 CFR 82.14 - What types of information could be used in dose reconstructions?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... THE ENERGY EMPLOYEES OCCUPATIONAL ILLNESS COMPENSATION PROGRAM ACT OF 2000 Dose Reconstruction Process... external exposure environment, including: radiation type (gamma, x-ray, proton, neutron, beta, other charged particle); radiation energy spectrum; uniformity of exposure (whole body vs partial body...

  19. 42 CFR 82.14 - What types of information could be used in dose reconstructions?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... THE ENERGY EMPLOYEES OCCUPATIONAL ILLNESS COMPENSATION PROGRAM ACT OF 2000 Dose Reconstruction Process... external exposure environment, including: radiation type (gamma, x-ray, proton, neutron, beta, other charged particle); radiation energy spectrum; uniformity of exposure (whole body vs partial body...

  20. 42 CFR 82.14 - What types of information could be used in dose reconstructions?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... THE ENERGY EMPLOYEES OCCUPATIONAL ILLNESS COMPENSATION PROGRAM ACT OF 2000 Dose Reconstruction Process... external exposure environment, including: radiation type (gamma, x-ray, proton, neutron, beta, other charged particle); radiation energy spectrum; uniformity of exposure (whole body vs partial body...

  1. 42 CFR 82.14 - What types of information could be used in dose reconstructions?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... THE ENERGY EMPLOYEES OCCUPATIONAL ILLNESS COMPENSATION PROGRAM ACT OF 2000 Dose Reconstruction Process... external exposure environment, including: radiation type (gamma, x-ray, proton, neutron, beta, other charged particle); radiation energy spectrum; uniformity of exposure (whole body vs partial body...

  2. Sequencing-by-hybridization revisited: the analog-spectrum proposal.

    PubMed

    Preparata, Franco P

    2004-01-01

    All published approaches to DNA sequencing by hybridization (SBH) consist of the biochemical acquisition of the spectrum of a target sequence (the set of its subsequences conforming to a given probing pattern) followed by the algorithmic reconstruction of the sequence from its spectrum. In the "standard" or "uniform" approach, the probing pattern is a string of length L and the length of reliably reconstructible sequences is known to be mlen = O(2(L)). For a fixed microarray area, higher sequencing performance can be achieved by inserting nonprobing gaps ("wild-cards") in the probing pattern. The reconstruction, however, must cope with the emergence of fooling probes due to the gaps and algorithmic failure occurs when the spectrum becomes too densely populated, although we can achieve mcomp = 0(4(L)). Despite the combinatorial success of gapped probing, all current approaches are based on a biochemically unrealistic spectrum-acquisition model (digital-spectrum). The reality of hybridization is much more complex. Departing from the conventional model, in this paper, we propose an alternative, called the analog-spectrum model, which more closely reflects the biochemical process. This novel modeling reestablishes probe length as the performance-governing factor, adopting "semidegenerate bases" as suitable emulators of currently inadequate universal bases. One important conclusion is that accurate biochemical measurements are pivotal to the success of SBH. The theoretical proposal presented in this paper should be a convincing stimulus for the needed biotechnological work. PMID:17048407

  3. Keyhole Flap Nipple Reconstruction

    PubMed Central

    Cash, Camille G.; Iman, Al-Haj; Spiegel, Aldona J.; Cronin, Ernest D.

    2016-01-01

    Summary: Nipple-areola reconstruction is often one of the final but most challenging aspects of breast reconstruction. However, it is an integral and important component of breast reconstruction because it transforms the mound into a breast. We performed 133 nipple-areola reconstructions during a period of 4 years. Of these reconstructions, 76 of 133 nipple-areola complexes were reconstructed using the keyhole flap technique. The tissue used for the keyhole dermoadipose flap technique include transverse rectus abdominus myocutaneous flaps (60/76), latissimus dorsi flaps (15/76), or mastectomy skin flaps after tissue expanders (1/76). The average patient follow-up was 17 months. The design of the flap is based on a keyhole configuration. The base of the flap determines the width of the future nipple, whereas the length of the flap determines the projection. We try to match the projection of the contralateral nipple if present. The keyhole flap is simple to construct yet reliable. It provides good symmetry and projection and avoids the creation of new scars. The areola is then tattooed approximately 3 months after the nipple reconstruction.

  4. Keyhole Flap Nipple Reconstruction.

    PubMed

    Chen, Joseph I; Cash, Camille G; Iman, Al-Haj; Spiegel, Aldona J; Cronin, Ernest D

    2016-05-01

    Nipple-areola reconstruction is often one of the final but most challenging aspects of breast reconstruction. However, it is an integral and important component of breast reconstruction because it transforms the mound into a breast. We performed 133 nipple-areola reconstructions during a period of 4 years. Of these reconstructions, 76 of 133 nipple-areola complexes were reconstructed using the keyhole flap technique. The tissue used for the keyhole dermoadipose flap technique include transverse rectus abdominus myocutaneous flaps (60/76), latissimus dorsi flaps (15/76), or mastectomy skin flaps after tissue expanders (1/76). The average patient follow-up was 17 months. The design of the flap is based on a keyhole configuration. The base of the flap determines the width of the future nipple, whereas the length of the flap determines the projection. We try to match the projection of the contralateral nipple if present. The keyhole flap is simple to construct yet reliable. It provides good symmetry and projection and avoids the creation of new scars. The areola is then tattooed approximately 3 months after the nipple reconstruction. PMID:27579228

  5. Reconstruction of the Mars Science Laboratory Parachute Performance and Comparison to the Descent Simulation

    NASA Technical Reports Server (NTRS)

    Cruz, Juan R.; Way, David W.; Shidner, Jeremy D.; Davis, Jody L.; Adams, Douglas S.; Kipp, Devin M.

    2013-01-01

    The Mars Science Laboratory used a single mortar-deployed disk-gap-band parachute of 21.35 m nominal diameter to assist in the landing of the Curiosity rover on the surface of Mars. The parachute system s performance on Mars has been reconstructed using data from the on-board inertial measurement unit, atmospheric models, and terrestrial measurements of the parachute system. In addition, the parachute performance results were compared against the end-to-end entry, descent, and landing (EDL) simulation created to design, develop, and operate the EDL system. Mortar performance was nominal. The time from mortar fire to suspension lines stretch (deployment) was 1.135 s, and the time from suspension lines stretch to first peak force (inflation) was 0.635 s. These times were slightly shorter than those used in the simulation. The reconstructed aerodynamic portion of the first peak force was 153.8 kN; the median value for this parameter from an 8,000-trial Monte Carlo simulation yielded a value of 175.4 kN - 14% higher than the reconstructed value. Aeroshell dynamics during the parachute phase of EDL were evaluated by examining the aeroshell rotation rate and rotational acceleration. The peak values of these parameters were 69.4 deg/s and 625 deg/sq s, respectively, which were well within the acceptable range. The EDL simulation was successful in predicting the aeroshell dynamics within reasonable bounds. The average total parachute force coefficient for Mach numbers below 0.6 was 0.624, which is close to the pre-flight model nominal drag coefficient of 0.615.

  6. Nasal reconstruction after epithelioma.

    PubMed

    Rodríguez-Camps, S

    2001-01-01

    In this paper we present our procedure for the treatment, histopathological diagnosis, and resection of skin cancer in the nasal pyramid and its subsequent reconstruction. Because we are dealing with the most important anatomical feature of the face our goal is an aesthetic reconstruction [2,4] according to the anatomical subunits criterion of Burget [3]. First, a histopathological diagnosis is made to determine the nature of the tumor. Then, we proceed with the resection according to the Mohs Micrographic Surgery [1,5,7]. Then we begin with the first step of the nasal reconstruction. PMID:11568830

  7. Evolutionary reconstruction of networks

    NASA Astrophysics Data System (ADS)

    Ipsen, Mads; Mikhailov, Alexander S.

    2002-10-01

    Can a graph specifying the pattern of connections of a dynamical network be reconstructed from statistical properties of a signal generated by such a system? In this model study, we present a Metropolis algorithm for reconstruction of graphs from their Laplacian spectra. Through a stochastic process of mutations and selection, evolving test networks converge to a reference graph. Applying the method to several examples of random graphs, clustered graphs, and small-world networks, we show that the proposed stochastic evolution allows exact reconstruction of relatively small networks and yields good approximations in the case of large sizes.

  8. Accelerating Spectrum Sharing Technologies

    SciTech Connect

    Juan D. Deaton; Lynda L. Brighton; Rangam Subramanian; Hussein Moradi; Jose Loera

    2013-09-01

    Spectrum sharing potentially holds the promise of solving the emerging spectrum crisis. However, technology innovators face the conundrum of developing spectrum sharing technologies without the ability to experiment and test with real incumbent systems. Interference with operational incumbents can prevent critical services, and the cost of deploying and operating an incumbent system can be prohibitive. Thus, the lack of incumbent systems and frequency authorization for technology incubation and demonstration has stymied spectrum sharing research. To this end, industry, academia, and regulators all require a test facility for validating hypotheses and demonstrating functionality without affecting operational incumbent systems. This article proposes a four-phase program supported by our spectrum accountability architecture. We propose that our comprehensive experimentation and testing approach for technology incubation and demonstration will accelerate the development of spectrum sharing technologies.

  9. A Reconstruction of Ultraviolet Spectral Irradiance During the Maunder Minimum

    NASA Astrophysics Data System (ADS)

    Bolduc, C.; Charbonneau, P.; Barnabé, R.; Bourqui, M. S.

    2014-08-01

    We present a reconstruction of the solar spectrum in the near and mid-ultraviolet spectral range during the Maunder Minimum, a period of strongly suppressed magnetic activity spanning the second half of the 17th century. This spectral reconstruction is based on an extension of the Monte Carlo Solar Spectral Irradiance Model (MOCASSIM). The new version of the model, documented in this paper, extends its spectral range down to 150 nm, its temporal range back to 1610, includes a secular modulation of the quiet-Sun emissivity based on a total solar irradiance reconstruction, and uses the Atmospheric Laboratory for Applications and Science-3 (ATLAS-3) spectrum as a reconstruction baseline. The model is validated against the ATLAS-1 spectrum for 29 March 1992, showing a general agreement varying from ˜ 1 % in the 300 - 400 nm range, up to 3 - 5 % below 200 nm, the largest discrepancies occurring in emission lines formed in the chromosphere and transition region. We also reconstruct ultraviolet spectra for May 2008 and March 2009, spanning the extended phase of low activity separating Cycles 23 and 24. Our results suggest that despite the unusually long temporal extent of this activity minimum, the ultraviolet emission still remained slightly higher than during the Maunder Minimum, due to the lingering presence of decay products from active regions having emerged in the late descending phase of Cycle 23.

  10. Nonlinear Simulation of the Tooth Enamel Spectrum for EPR Dosimetry

    NASA Astrophysics Data System (ADS)

    Kirillov, V. A.; Dubovsky, S. V.

    2016-07-01

    Software was developed where initial EPR spectra of tooth enamel were deconvoluted based on nonlinear simulation, line shapes and signal amplitudes in the model initial spectrum were calculated, the regression coefficient was evaluated, and individual spectra were summed. Software validation demonstrated that doses calculated using it agreed excellently with the applied radiation doses and the doses reconstructed by the method of additive doses.

  11. Advances in Tracheal Reconstruction

    PubMed Central

    Salna, Michael; Waddell, Thomas K.; Hofer, Stefan O.

    2014-01-01

    Summary: A recent revival of global interest for reconstruction of long-segment tracheal defects, which represents one of the most interesting and complex problems in head and neck and thoracic reconstructive surgery, has been witnessed. The trachea functions as a conduit for air, and its subunits including the epithelial layer, hyaline cartilage, and segmental blood supply make it particularly challenging to reconstruct. A myriad of attempts at replacing the trachea have been described. These along with the anatomy, indications, and approaches including microsurgical tracheal reconstruction will be reviewed. Novel techniques such as tissue-engineering approaches will also be discussed. Multiple attempts at replacing the trachea with synthetic scaffolds have been met with failure. The main lesson learned from such failures is that the trachea must not be treated as a “simple tube.” Understanding the anatomy, developmental biology, physiology, and diseases affecting the trachea are required for solving this problem. PMID:25426361

  12. Breast Reconstruction After Mastectomy

    MedlinePlus

    ... Women who have autologous tissue reconstruction may need physical therapy to help them make up for weakness experienced ... 127(1):15–22. [PubMed Abstract] Monteiro M. Physical therapy implications following the TRAM procedure. Physical Therapy. 1997; ...

  13. Breast Reconstruction and Prosthesis

    MedlinePlus

    ... feel of the breast after a mastectomy. A plastic surgeon can do it at the same time ... want breast reconstruction. • Have you talked with your plastic surgeon about your options? You may not be ...

  14. Reconstruction of Mandibular Defects

    PubMed Central

    Chim, Harvey; Salgado, Christopher J.; Mardini, Samir; Chen, Hung-Chi

    2010-01-01

    Defects requiring reconstruction in the mandible are commonly encountered and may result from resection of benign or malignant lesions, trauma, or osteoradionecrosis. Mandibular defects can be classified according to location and extent, as well as involvement of mucosa, skin, and tongue. Vascularized bone flaps, in general, provide the best functional and aesthetic outcome, with the fibula flap remaining the gold standard for mandible reconstruction. In this review, we discuss classification and approach to reconstruction of mandibular defects. We also elaborate upon four commonly used free osteocutaneous flaps, inclusive of fibula, iliac crest, scapula, and radial forearm. Finally, we discuss indications and use of osseointegrated implants as well as recent advances in mandibular reconstruction. PMID:22550439

  15. Overview of Image Reconstruction

    SciTech Connect

    Marr, R. B.

    1980-04-01

    Image reconstruction (or computerized tomography, etc.) is any process whereby a function, f, on Rn is estimated from empirical data pertaining to its integrals, ∫f(x) dx, for some collection of hyperplanes of dimension k < n. The paper begins with background information on how image reconstruction problems have arisen in practice, and describes some of the application areas of past or current interest; these include radioastronomy, optics, radiology and nuclear medicine, electron microscopy, acoustical imaging, geophysical tomography, nondestructive testing, and NMR zeugmatography. Then the various reconstruction algorithms are discussed in five classes: summation, or simple back-projection; convolution, or filtered back-projection; Fourier and other functional transforms; orthogonal function series expansion; and iterative methods. Certain more technical mathematical aspects of image reconstruction are considered from the standpoint of uniqueness, consistency, and stability of solution. The paper concludes by presenting certain open problems. 73 references. (RWR)

  16. Aesthetic and Functional Outcomes of the Innervated and Thinned Anterolateral Thigh Flap in Reconstruction of Upper Limb Defects

    PubMed Central

    Torres-Ortíz Zermeño, Carlos Alberto; López Mendoza, Javier

    2014-01-01

    Background. The anterolateral thigh (ALT) flap has been widely described in reconstruction of the upper extremity. However, some details require refinement to improve both functional and aesthetic results. Methods. After reconstruction of upper extremity defects using thinned and innervated ALT flaps, functional and aesthetic outcomes were evaluated with the QuickDASH scale and a Likert scale for aesthetic assessment of free flaps, respectively. Results. Seven patients with a mean follow-up of 11.57 months and average flap thickness of 5 mm underwent innervation by an end-to-end neurorrhaphy. The average percentage of disability (QuickDASH) was 21.88% with tenderness, pain, temperature, and two-point discrimination present in 100% of cases, and the aesthetic result gave an overall result of 15.40 (good) with the best scores in color and texture. Conclusions. Simultaneous thinning and innervation of the ALT flap lead to a good cosmetic result and functional outcome with a low percentage of disability, which could result in minor surgical procedures and better recovery of motor and sensory function. Level of Evidence. IV. PMID:25478219

  17. Personalized Multilayer Daily Life Profiling Through Context Enabled Activity Classification and Motion Reconstruction: An Integrated System Approach.

    PubMed

    Xu, James Y; Wang, Yan; Barrett, Mick; Dobkin, Bruce; Pottie, Greg J; Kaiser, William J

    2016-01-01

    Profiling the daily activity of a physically disabled person in the community would enable healthcare professionals to monitor the type, quantity, and quality of their patients' compliance with recommendations for exercise, fitness, and practice of skilled movements, as well as enable feedback about performance in real-world situations. Based on our early research in in-community activity profiling, we present in this paper an end-to-end system capable of reporting a patient's daily activity at multiple levels of granularity: 1) at the highest level, information on the location categories a patient is able to visit; 2) within each location category, information on the activities a patient is able to perform; and 3) at the lowest level, motion trajectory, visualization, and metrics computation of each activity. Our methodology is built upon a physical activity prescription model coupled with MEMS inertial sensors and mobile device kits that can be sent to a patient at home. A novel context-guided activity-monitoring concept with categorical location context is used to achieve enhanced classification accuracy and throughput. The methodology is then seamlessly integrated with motion reconstruction and metrics computation to provide comprehensive layered reporting of a patient's daily life. We also present an implementation of the methodology featuring a novel location context detection algorithm using WiFi augmented GPS and overlays, with motion reconstruction and visualization algorithms for practical in-community deployment. Finally, we use a series of experimental field evaluations to confirm the accuracy of the system. PMID:25546868

  18. Pinnacle3 modeling and end-to-end dosimetric testing of a Versa HD linear accelerator with the Agility head and flattening filter-free modes.

    PubMed

    Saenz, Daniel L; Narayanasamy, Ganesh; Cruz, Wilbert; Papanikolaou, Nikos; Stathakis, Sotirios

    2016-01-01

    The Elekta Versa HD incorporates a variety of upgrades to the line of Elekta linear accelerators, primarily including the Agility head and flattening filter-free (FFF) photon beam delivery. The completely distinct dosimetric output of the head from its predecessors, combined with the FFF beams, requires a new investigation of modeling in treatment planning systems. A model was created in Pinnacle3 v9.8 with the commissioned beam data. A phantom consisting of several plastic water and Styrofoam slabs was scanned and imported into Pinnacle3, where beams of different field sizes, source-to-surface distances (SSDs), wedges, and gantry angles were devised. Beams included all of the available photon energies (6, 10, 18, 6FFF, and 10 FFF MV), as well as the four electron energies commissioned for clinical use (6, 9, 12, and 15 MeV). The plans were verified at calculation points by measurement with a calibrated ionization chamber. Homogeneous and hetero-geneous point-dose measurements agreed within 2% relative to maximum dose for all photon and electron beams. AP photon open field measurements along the central axis at 100 cm SSD passed within 1%. In addition, IMRT testing was also performed with three standard plans (step and shoot IMRT, as well as a small- and large-field VMAT plan). The IMRT plans were delivered on the Delta4 IMRT QA phantom, for which a gamma passing rate was > 99.5% for all plans with a 3% dose deviation, 3 mm distance-to-agreement, and 10% dose threshold. The IMRT QA results for the first 23 patients yielded gamma passing rates of 97.4% ± 2.3%. Such testing ensures confidence in the ability of Pinnacle3 to model photon and electron beams with the Agility head. PMID:26894352

  19. EXSdetect: an end-to-end software for extended source detection in X-ray images: application to Swift-XRT data

    NASA Astrophysics Data System (ADS)

    Liu, T.; Tozzi, P.; Tundo, E.; Moretti, A.; Wang, J.-X.; Rosati, P.; Guglielmetti, F.

    2013-01-01

    Aims: We present a stand-alone software (named EXSdetect) for the detection of extended sources in X-ray images. Our goal is to provide a flexible tool capable of detecting extended sources down to the lowest flux levels attainable within instrumental limitations, while maintaining robust photometry, high completeness, and low contamination, regardless of source morphology. EXSdetect was developed mainly to exploit the ever-increasing wealth of archival X-ray data, but is also ideally suited to explore the scientific capabilities of future X-ray facilities, with a strong focus on investigations of distant groups and clusters of galaxies. Methods: EXSdetect combines a fast Voronoi tessellation code with a friends-of-friends algorithm and an automated deblending procedure. The values of key parameters are matched to fundamental telescope properties such as angular resolution and instrumental background. In addition, the software is designed to permit extensive tests of its performance via simulations of a wide range of observational scenarios. Results: We applied EXSdetect to simulated data fields modeled to realistically represent the Swift X-ray Cluster Survey (SXCS), which is based on archival data obtained by the X-ray telescope onboard the Swift satellite. We achieve more than 90% completeness for extended sources comprising at least 80 photons in the 0.5-2 keV band, a limit that corresponds to 10-14 erg cm-2 s-1 for the deepest SXCS fields. This detection limit is comparable to the one attained by the most sensitive cluster surveys conducted with much larger X-ray telescopes. While evaluating the performance of EXSdetect, we also explored the impact of improved angular resolution and discuss the ideal properties of the next generation of X-ray survey missions. The Phyton code EXSdetect is available on the SXCS website http://adlibitum.oats.inaf.it/sxcs

  20. 'End to end' planktonic trophic web and its implications for the mussel farms in the Mar Piccolo of Taranto (Ionian Sea, Italy).

    PubMed

    Karuza, Ana; Caroppo, Carmela; Monti, Marina; Camatti, Elisa; Di Poi, Elena; Stabili, Loredana; Auriemma, Rocco; Pansera, Marco; Cibic, Tamara; Del Negro, Paola

    2016-07-01

    The Mar Piccolo is a semi-enclosed basin subject to different natural and anthropogenic stressors. In order to better understand plankton dynamics and preferential carbon pathways within the planktonic trophic web, an integrated approach was adopted for the first time by examining all trophic levels (virioplankton, the heterotrophic and phototrophic fractions of pico-, nano- and microplankton, as well as mesozooplankton). Plankton abundance and biomass were investigated during four surveys in the period 2013-2014. Beside unveiling the dynamics of different plankton groups in the Mar Piccolo, the study revealed that high portion of the plankton carbon (C) pool was constituted by small-sized (<2 μm) planktonic fractions. The prevalence of small-sized species within micro- and mesozooplankton communities was observed as well. The succession of planktonic communities was clearly driven by the seasonality, i.e. by the nutrient availability and physical features of the water column. Our hypothesis is that beside the 'bottom-up' control and the grazing pressure, inferred from the C pools of different plankton groups, the presence of mussel farms in the Mar Piccolo exerts a profound impact on plankton communities, not only due to the important sequestration of the plankton biomass but also by strongly influencing its structure. PMID:26498814

  1. End-to-End System Test of the Relative Precision and Stability of the Photometric Method for Detecting Earth-Size Extrasolar Planets

    NASA Technical Reports Server (NTRS)

    Dunham, Edward W.

    2000-01-01

    We developed the CCD camera system for the laboratory test demonstration and designed the optical system for this test. The camera system was delivered to Ames in April, 1999 with continuing support mostly in the software area as the test progressed. The camera system has been operating successfully since delivery. The optical system performed well during the test. The laboratory demonstration activity is now nearly complete and is considered to be successful by the Technical Advisory Group, which met on 8 February, 2000 at the SETI Institute. A final report for the Technical Advisory Group and NASA Headquarters will be produced in the next few months. This report will be a comprehensive report on all facets of the test including those covered under this grant. A copy will be forwarded, if desired, when it is complete.

  2. SU-E-T-508: End to End Testing of a Prototype Eclipse Module for Planning Modulated Arc Therapy On the Siemens Platform

    SciTech Connect

    Huang, L; Sarkar, V; Spiessens, S; Rassiah-Szegedi, P; Huang, Y; Salter, B; Zhao, H; Szegedi, M

    2014-06-01

    Purpose: The latest clinical implementation of the Siemens Artiste linac allows for delivery of modulated arcs (mARC) using full-field flattening filter free (FFF) photon beams. The maximum doserate of 2000 MU/min is well suited for high dose treatments such as SBRT. We tested and report on the performance of a prototype Eclipse TPS module supporting mARC capability on the Artiste platform. Method: our spine SBRT patients originally treated with 12/13 field static-gantry IMRT (SGIMRT) were chosen for this study. These plans were designed to satisfy RTOG0631 guidelines with a prescription of 16Gy in a single fraction. The cases were re-planned as mARC plans in the prototype Eclipse module using the 7MV FFF beam and required to satisfy RTOG0631 requirements. All plans were transferred from Eclipse, delivered on a Siemens Artiste linac and dose-validated using the Delta4 system. Results: All treatment plans were straightforwardly developed, in timely fashion, without challenge or inefficiency using the prototype module. Due to the limited number of segments in a single arc, mARC plans required 2-3 full arcs to yield plan quality comparable to SGIMRT plans containing over 250 total segments. The average (3%/3mm) gamma pass-rate for all arcs was 98.5±1.1%, thus demonstrating both excellent dose prediction by the AAA dose algorithm and excellent delivery fidelity. Mean delivery times for the mARC plans(10.5±1.7min) were 50-70% lower than the SGIMRT plans(26±2min), with both delivered at 2000 MU/min. Conclusion: A prototype Eclipse module capable of planning for Burst Mode modulated arc delivery on the Artiste platform has been tested and found to perform efficiently and accurately for treatment plan development and delivered-dose prediction. Further investigation of more treatment sites is being carried out and data will be presented.

  3. End-to-end connectivity utility-based two-way network offers wireless option for home and business information services

    SciTech Connect

    Barth, S.

    1997-06-01

    Faster. Cheaper. Better. That`s the battle cry for utility and communications industries as information technologies merge and a new laissez faire attitude toward competition emerges from regulatory agencies. Telecommunications and cable companies loom as likely contenders to capitalize on these changes. However, with equal, perhaps better access to consumer bases, utility companies are positioning themselves as competitors on this newly leveled playing field. The playing field has not only been leveled, but is now vastly expanded. The utility company used to view its principle requirement as the ability to meet the needs of its existing service territory. Now to survive in the age of a newly competitive arena, the utility company must not only look at methods for maintaining its existing customers, but also at how to acquire customers outside its service territory. The deregulation of the telecom industry has provided the utility company with some additional breathing room in establishing strategies and methods for how it will maintain its customers. While the major telecommunications players continue to battle each other for the opportunity to provide both local and long distance service, utility companies have gained a bit of time to enable them to develop the services that can be offered directly to their existing customer base via power lines or other existing utility infrastructure. By integrating commercial wireless communications services with their existing power lines, electric companies are insulating themselves against competitors in their own field, as well as making new services available to their customers. With applications such as automatic meter reading and service monitoring capabilities for themselves and value-added services from outside vendors for their consumers, utilities can carve out a strong niche in their existing marketplace while moving into new territory.

  4. Design and implementation of a secure and user-friendly broker platform supporting the end-to-end provisioning of e-homecare services.

    PubMed

    Van Hoecke, Sofie; Steurbaut, Kristof; Taveirne, Kristof; De Turck, Filip; Dhoedt, Bart

    2010-01-01

    We designed a broker platform for e-homecare services using web service technology. The broker allows efficient data communication and guarantees quality requirements such as security, availability and cost-efficiency by dynamic selection of services, minimizing user interactions and simplifying authentication through a single user sign-on. A prototype was implemented, with several e-homecare services (alarm, telemonitoring, audio diary and video-chat). It was evaluated by patients with diabetes and multiple sclerosis. The patients found that the start-up time and overhead imposed by the platform was satisfactory. Having all e-homecare services integrated into a single application, which required only one login, resulted in a high quality of experience for the patients. PMID:20086267

  5. SU-E-J-55: End-To-End Effectiveness Analysis of 3D Surface Image Guided Voluntary Breath-Holding Radiotherapy for Left Breast

    SciTech Connect

    Lin, M; Feigenberg, S

    2015-06-15

    Purpose To evaluate the effectiveness of using 3D-surface-image to guide breath-holding (BH) left-side breast treatment. Methods Two 3D surface image guided BH procedures were implemented and evaluated: normal-BH, taking BH at a comfortable level, and deep-inspiration-breath-holding (DIBH). A total of 20 patients (10 Normal-BH and 10 DIBH) were recruited. Patients received a BH evaluation using a commercialized 3D-surface- tracking-system (VisionRT, London, UK) to quantify the reproducibility of BH positions prior to CT scan. Tangential 3D/IMRT plans were conducted. Patients were initially setup under free-breathing (FB) condition using the FB surface obtained from the untaged CT to ensure a correct patient position. Patients were then guided to reach the planned BH position using the BH surface obtained from the BH CT. Action-levels were set at each phase of treatment process based on the information provided by the 3D-surface-tracking-system for proper interventions (eliminate/re-setup/ re-coaching). We reviewed the frequency of interventions to evaluate its effectiveness. The FB-CBCT and port-film were utilized to evaluate the accuracy of 3D-surface-guided setups. Results 25% of BH candidates with BH positioning uncertainty > 2mm are eliminated prior to CT scan. For >90% of fractions, based on the setup deltas from3D-surface-trackingsystem, adjustments of patient setup are needed after the initial-setup using laser. 3D-surface-guided-setup accuracy is comparable as CBCT. For the BH guidance, frequency of interventions (a re-coaching/re-setup) is 40%(Normal-BH)/91%(DIBH) of treatments for the first 5-fractions and then drops to 16%(Normal-BH)/46%(DIBH). The necessity of re-setup is highly patient-specific for Normal-BH but highly random among patients for DIBH. Overall, a −0.8±2.4 mm accuracy of the anterior pericardial shadow position was achieved. Conclusion 3D-surface-image technology provides effective intervention to the treatment process and ensures favorable day-to-day setup accuracy. DIBH setup appears to be more uncertain and this would be the patient group who will definitely benefit from the extra information of 3D surface setup.

  6. PICASSO: an end-to-end image simulation tool for space and airborne imaging systems II. Extension to the thermal infrared: equations and methods

    NASA Astrophysics Data System (ADS)

    Cota, Stephen A.; Lomheim, Terrence S.; Florio, Christopher J.; Harbold, Jeffrey M.; Muto, B. Michael; Schoolar, Richard B.; Wintz, Daniel T.; Keller, Robert A.

    2011-10-01

    In a previous paper in this series, we described how The Aerospace Corporation's Parameterized Image Chain Analysis & Simulation SOftware (PICASSO) tool may be used to model space and airborne imaging systems operating in the visible to near-infrared (VISNIR). PICASSO is a systems-level tool, representative of a class of such tools used throughout the remote sensing community. It is capable of modeling systems over a wide range of fidelity, anywhere from conceptual design level (where it can serve as an integral part of the systems engineering process) to as-built hardware (where it can serve as part of the verification process). In the present paper, we extend the discussion of PICASSO to the modeling of Thermal Infrared (TIR) remote sensing systems, presenting the equations and methods necessary to modeling in that regime.

  7. Orthogonal labeling of M13 minor capsid proteins with DNA to self-assemble end-to-end multi-phage structures

    PubMed Central

    Hess, Gaelen T.; Guimaraes, Carla P.; Spooner, Eric; Ploegh, Hidde L.; Belcher, Angela M.

    2014-01-01

    M13 bacteriophage has been used as a scaffold to organize materials for various applications. Building more complex multi-phage devices requires precise control of interactions between the M13 capsid proteins. Towards this end, we engineered a loop structure onto the pIII capsid protein of M13 bacteriophage to enable sortase-mediated labeling reactions for C-terminal display. Combining this with N-terminal sortase-mediated labeling, we thus created a phage scaffold that can be labeled orthogonally on three capsid proteins: the body and both ends. We show that covalent attachment of different DNA oligonucleotides at the ends of the new phage structure enables formation of multi-phage particles oriented in a specific order. These have potential as nanoscale scaffolds for multi–material devices. PMID:23713956

  8. Niti CAR 27 Versus a Conventional End-to-End Anastomosis Stapler in a Laparoscopic Anterior Resection for Sigmoid Colon Cancer

    PubMed Central

    Kwag, Seung-Jin; Kim, Jun-Gi; Kang, Won-Kyung; Lee, Jin-Kwon

    2014-01-01

    Purpose The Niti CAR 27 (ColonRing) uses compression to create an anastomosis. This study aimed to investigate the safety and the effectiveness of the anastomosis created with the Niti CAR 27 in a laparoscopic anterior resection for sigmoid colon cancer. Methods In a single-center study, 157 consecutive patients who received an operation between March 2010 and December 2011 were retrospectively assessed. The Niti CAR 27 (CAR group, 63 patients) colorectal anastomoses were compared with the conventional double-stapled (CDS group, 94 patients) colorectal anastomoses. Intraoperative, immediate postoperative and 6-month follow-up data were recorded. Results There were no statistically significant differences between the two groups in terms of age, gender, tumor location and other clinical characteristics. One patient (1.6%) in the CAR group and 2 patients (2.1%) in the CDS group experienced complications of anastomotic leakage (P = 0.647). These three patients underwent a diverting loop ileostomy. There were 2 cases (2.1%) of bleeding at the anastomosis site in the CDS group. All patients underwent a follow-up colonoscopy (median, 6 months). One patient in the CAR group experienced anastomotic stricture (1.6% vs. 0%; P = 0.401). This complication was solved by using balloon dilatation. Conclusion Anastomosis using the Niti CAR 27 device in a laparoscopic anterior resection for sigmoid colon cancer is safe and feasible. Its use is equivalent to that of the conventional double-stapler. PMID:24851217

  9. From Ambient Sensing to IoT-based Context Computing: An Open Framework for End to End QoC Management †

    PubMed Central

    Marie, Pierrick; Desprats, Thierry; Chabridon, Sophie; Sibilla, Michelle; Taconet, Chantal

    2015-01-01

    Quality of Context (QoC) awareness is recognized as a key point for the success of context-aware computing. At the time where the combination of the Internet of Things, Cloud Computing, and Ambient Intelligence paradigms offer together new opportunities for managing richer context data, the next generation of Distributed Context Managers (DCM) is facing new challenges concerning QoC management. This paper presents our model-driven QoCIM framework. QoCIM is the acronym for Quality of Context Information Model. We show how it can help application developers to manage the whole QoC life-cycle by providing genericity, openness and uniformity. Its usages are illustrated, both at design time and at runtime, in the case of an urban pollution context- and QoC-aware scenario. PMID:26087372

  10. From Ambient Sensing to IoT-based Context Computing: An Open Framework for End to End QoC Management.

    PubMed

    Marie, Pierrick; Desprats, Thierry; Chabridon, Sophie; Sibilla, Michelle; Taconet, Chantal

    2015-01-01

    Quality of Context (QoC) awareness is recognized as a key point for the success of context-aware computing. At the time where the combination of the Internet of Things, Cloud Computing, and Ambient Intelligence paradigms offer together new opportunities for managing richer context data, the next generation of Distributed Context Managers (DCM) is facing new challenges concerning QoC management. This paper presents our model-driven QoCIM framework. QoCIM is the acronym for Quality of Context Information Model. We show how it can help application developers to manage the whole QoC life-cycle by providing genericity, openness and uniformity. Its usages are illustrated, both at design time and at runtime, in the case of an urban pollution context- and QoC-aware scenario. PMID:26087372

  11. Free-energy landscape of mechanically unfolded model proteins: Extended Jarzinsky versus inherent structure reconstruction

    NASA Astrophysics Data System (ADS)

    Luccioli, Stefano; Imparato, Alberto; Torcini, Alessandro

    2008-09-01

    The equilibrium free-energy landscape of off-lattice model heteropolymers as a function of an internal coordinate, namely the end-to-end distance, is reconstructed from out-of-equilibrium steered molecular dynamics data. This task is accomplished via two independent methods: By employing an extended version of the Jarzynski equality and the inherent structure formalism. A comparison of the free energies estimated with these two schemes with equilibrium results obtained via the umbrella sampling technique reveals a good quantitative agreement among all the approaches in a range of temperatures around the “folding transition” for the two examined sequences. In particular, for the sequence with good foldability properties, the mechanically induced structural transitions can be related to thermodynamical aspects of folding. Moreover, for the same sequence the knowledge of the landscape profile allows for a good estimation of the lifetimes of the native configuration for temperatures ranging from the folding to the collapse temperature. For the random sequence, mechanical and thermal unfolding appear to follow different paths along the landscape.

  12. Efficient reconstruction method for ground layer adaptive optics with mixed natural and laser guide stars.

    PubMed

    Wagner, Roland; Helin, Tapio; Obereder, Andreas; Ramlau, Ronny

    2016-02-20

    The imaging quality of modern ground-based telescopes such as the planned European Extremely Large Telescope is affected by atmospheric turbulence. In consequence, they heavily depend on stable and high-performance adaptive optics (AO) systems. Using measurements of incoming light from guide stars, an AO system compensates for the effects of turbulence by adjusting so-called deformable mirror(s) (DMs) in real time. In this paper, we introduce a novel reconstruction method for ground layer adaptive optics. In the literature, a common approach to this problem is to use Bayesian inference in order to model the specific noise structure appearing due to spot elongation. This approach leads to large coupled systems with high computational effort. Recently, fast solvers of linear order, i.e., with computational complexity O(n), where n is the number of DM actuators, have emerged. However, the quality of such methods typically degrades in low flux conditions. Our key contribution is to achieve the high quality of the standard Bayesian approach while at the same time maintaining the linear order speed of the recent solvers. Our method is based on performing a separate preprocessing step before applying the cumulative reconstructor (CuReD). The efficiency and performance of the new reconstructor are demonstrated using the OCTOPUS, the official end-to-end simulation environment of the ESO for extremely large telescopes. For more specific simulations we also use the MOST toolbox. PMID:26906596

  13. Performance comparison of wavefront reconstruction and control algorithms for Extremely Large Telescopes.

    PubMed

    Montilla, I; Béchet, C; Le Louarn, M; Reyes, M; Tallon, M

    2010-11-01

    Extremely Large Telescopes (ELTs) are very challenging with respect to their adaptive optics (AO) requirements. Their diameters and the specifications required by the astronomical science for which they are being designed imply a huge increment in the number of degrees of freedom in the deformable mirrors. Faster algorithms are needed to implement the real-time reconstruction and control in AO at the required speed. We present the results of a study of the AO correction performance of three different algorithms applied to the case of a 42-m ELT: one considered as a reference, the matrix-vector multiply (MVM) algorithm; and two considered fast, the fractal iterative method (FrIM) and the Fourier transform reconstructor (FTR). The MVM and the FrIM both provide a maximum a posteriori estimation, while the FTR provides a least-squares one. The algorithms are tested on the European Southern Observatory (ESO) end-to-end simulator, OCTOPUS. The performance is compared using a natural guide star single-conjugate adaptive optics configuration. The results demonstrate that the methods have similar performance in a large variety of simulated conditions. However, with respect to system misregistrations, the fast algorithms demonstrate an interesting robustness. PMID:21045895

  14. Fast Image Reconstruction with L2-Regularization

    PubMed Central

    Bilgic, Berkin; Chatnuntawech, Itthi; Fan, Audrey P.; Setsompop, Kawin; Cauley, Stephen F.; Wald, Lawrence L.; Adalsteinsson, Elfar

    2014-01-01

    Purpose We introduce L2-regularized reconstruction algorithms with closed-form solutions that achieve dramatic computational speed-up relative to state of the art L1- and L2-based iterative algorithms while maintaining similar image quality for various applications in MRI reconstruction. Materials and Methods We compare fast L2-based methods to state of the art algorithms employing iterative L1- and L2-regularization in numerical phantom and in vivo data in three applications; 1) Fast Quantitative Susceptibility Mapping (QSD), 2) Lipid artifact suppression in Magnetic Resonance Spectroscopic Imaging (MRSI), and 3) Diffusion Spectrum Imaging (DSI). In all cases, proposed L2-based methods are compared with the state of the art algorithms, and two to three orders of magnitude speed up is demonstrated with similar reconstruction quality. Results The closed-form solution developed for regularized QSM allows processing of a 3D volume under 5 seconds, the proposed lipid suppression algorithm takes under 1 second to reconstruct single-slice MRSI data, while the PCA based DSI algorithm estimates diffusion propagators from undersampled q-space for a single slice under 30 seconds, all running in Matlab using a standard workstation. Conclusion For the applications considered herein, closed-form L2-regularization can be a faster alternative to its iterative counterpart or L1-based iterative algorithms, without compromising image quality. PMID:24395184

  15. Cosmic tidal reconstruction

    NASA Astrophysics Data System (ADS)

    Zhu, Hong-Ming; Pen, Ue-Li; Yu, Yu; Er, Xinzhong; Chen, Xuelei

    2016-05-01

    The gravitational coupling of a long-wavelength tidal field with small-scale density fluctuations leads to anisotropic distortions of the locally measured small-scale matter correlation function. Since the local correlation function is known to be statistically isotropic in the absence of such tidal interactions, the tidal distortions can be used to reconstruct the long-wavelength tidal field and large-scale density field in analogy with the cosmic microwave background lensing reconstruction. In this paper we present the theoretical framework of cosmic tidal reconstruction and test the reconstruction in numerical simulations. We find that the density field on large scales can be reconstructed with good accuracy and the cross-correlation coefficient between the reconstructed density field and the original density field is greater than 0.9 on large scales (k ≲0.1 h /Mpc ), with the filter scale ˜1.25 Mpc /h . This is useful in the 21 cm intensity mapping survey, where the long-wavelength radial modes are lost due to a foreground subtraction process.

  16. Microsurgical breast reconstruction.

    PubMed

    Avraham, Tomer; Clavin, Nicolas; Mehrara, Babak J

    2008-01-01

    Breast cancer, the most common cancer diagnosed in American women, often necessitates mastectomy. Many studies have demonstrated improved quality of life and well-being after breast reconstruction. Numerous techniques are available for breast reconstruction including tissue expander implants and autologous tissues. Microsurgical tissue transfer involves the use of excess skin and fat (flaps) from a remote location to reconstruct the breast. Most often, tissues are transferred from the abdomen and buttocks. Less commonly, thigh flaps are used. These operations can provide durable, esthetic reconstructions. In addition, advances in microsurgical techniques have improved operative success rates to the range of 99%. The selection of an appropriate flap for microsurgical breast reconstruction is multifactorial and is based on patient and oncologic factors. These factors include patient comorbidities, body habitus/availability of donor tissues, cancer stage, and the need for postoperative adjuvant radiation therapy, as well as the risk of cancer in the contralateral breast. Appropriate choice of flap and surgical technique can minimize the risk of operative complications. Additionally, several large series have established that microsurgical breast reconstruction has no impact on survival, or locoregional/distant recurrence rates. PMID:18677132

  17. The Reconstruction Problem Revisited

    NASA Technical Reports Server (NTRS)

    Suresh, Ambaby

    1999-01-01

    The role of reconstruction in avoiding oscillations in upwind schemes is reexamined, with the aim of providing simple, concise proofs. In one dimension, it is shown that if the reconstruction is any arbitrary function bounded by neighboring cell averages and increasing within a cell for increasing data, the resulting scheme is monotonicity preserving, even though the reconstructed function may have overshoots and undershoots at the cell edges and is in general not a monotone function. In the special case of linear reconstruction, it is shown that merely bounding the reconstruction between neighboring cell averages is sufficient to obtain a monotonicity preservinc,y scheme. In two dimensions, it is shown that some ID TVD limiters applied in each direction result in schemes that are not positivity preserving, i.e. do not give positive updates when the data are positive. A simple proof is given to show that if the reconstruction inside the cell is bounded by the neighboring cell averages (including corner neighbors), then the scheme is positivity preserving. A new limiter that enforces this condition but is not as dissipative as the Minmod limiter is also presented.

  18. Radiation detector spectrum simulator

    DOEpatents

    Wolf, Michael A.; Crowell, John M.

    1987-01-01

    A small battery operated nuclear spectrum simulator having a noise source nerates pulses with a Gaussian distribution of amplitudes. A switched dc bias circuit cooperating therewith generates several nominal amplitudes of such pulses and a spectral distribution of pulses that closely simulates the spectrum produced by a radiation source such as Americium 241.

  19. Radiation detector spectrum simulator

    DOEpatents

    Wolf, M.A.; Crowell, J.M.

    1985-04-09

    A small battery operated nuclear spectrum simulator having a noise source generates pulses with a Gaussian distribution of amplitudes. A switched dc bias circuit cooperating therewith to generate several nominal amplitudes of such pulses and a spectral distribution of pulses that closely simulates the spectrum produced by a radiation source such as Americium 241.

  20. The CMBR spectrum

    SciTech Connect

    Stebbins, A.

    1997-05-01

    Here we give an introduction to the observed spectrum of the Cosmic Microwave Background Radiation (CMBR) and discuss what can be learned about it. Particular attention will be given to how Compton scattering can distort the spectrum of the CMBR. An incomplete bibliography of relevant papers is also provided.

  1. Fission Spectrum Related Uncertainties

    SciTech Connect

    G. Aliberti; I. Kodeli; G. Palmiotti; M. Salvatores

    2007-10-01

    The paper presents a preliminary uncertainty analysis related to potential uncertainties on the fission spectrum data. Consistent results are shown for a reference fast reactor design configuration and for experimental thermal configurations. However the results obtained indicate the need for further analysis, in particular in terms of fission spectrum uncertainty data assessment.

  2. Fetal Alcohol Spectrum Disorder

    ERIC Educational Resources Information Center

    Caley, Linda M.; Kramer, Charlotte; Robinson, Luther K.

    2005-01-01

    Fetal alcohol spectrum disorder (FASD) is a serious and widespread problem in this country. Positioned within the community with links to children, families, and healthcare systems, school nurses are a critical element in the prevention and treatment of those affected by fetal alcohol spectrum disorder. Although most school nurses are familiar…

  3. Effect of the fringe visibility on spectrum SNR of Fourier transform imaging spectrometer

    NASA Astrophysics Data System (ADS)

    Wang, Shuang; Bin, Xiangli; Jing, Juanjuan; Pi, Haifeng

    2013-08-01

    The principle of Fourier transform spectrometer is based on the relationship of Fourier-Transform between interferogram and spectrum. The spectral information of Fourier transform imaging spectrometer (FTIS) reconstructed from raw interferogram by data processing. So there are two kinds of signal-to-noise ratio (SNR) to evaluate instrument performance, one regarding interferogram and the other regarding reconstructed spectrum. Because the raw interferogram is intuitive, the interferogram SNR is studied usually. On the contrary, the spectrum SNR is studied less because of the complexity of the data processing from interferogram to spectrum. The research about the effect of the interference fringe visibility on the spectrum SNR is especially few. This paper present a research work on the relations between the interference fringe visibility and the spectrum SNR. Firstly, the reduction of fringe visibility caused by imaging lens defocus was analyzed. Secondly, the changes of the average spectrum signal and noise caused by the reduction of fringe visibility were calculated. For average spectrum signal, the math deductions are done base on Fourier transform theory. The average noise with different input signal optic-electrons number are simulated. the results show that the average spectrum signal is directly proportional to the fringe visibility, and the effect of fringe visibility on the noise related to signal can be ignorable. Finally, In order to demonstrate above results, the imaging experiment was done with white-light source, using LASIS (Large aperture static imaging spectrometer) based on Sagnac Interferometer. The average spectrum SNRs under different fringe visibility are calculated and analyzed. The experimental results show that: the average spectrum SNRs increase from 42.7 to 62.4.along with the fringe visibility increasing from 0.5051 to 0.687. the reconstructed spectrum SNR is directly proportional to the fringe visibility. As a result, the interferogram

  4. Hypoglossal-Facial Nerve Reconstruction Using a Y-Tube-Conduit Reduces Aberrant Synkinetic Movements of the Orbicularis Oculi and Vibrissal Muscles in Rats

    PubMed Central

    Kaya, Yasemin; Ozsoy, Umut; Turhan, Murat; Angelov, Doychin N.; Sarikcioglu, Levent

    2014-01-01

    The facial nerve is the most frequently damaged nerve in head and neck trauma. Patients undergoing facial nerve reconstruction often complain about disturbing abnormal synkinetic movements of the facial muscles (mass movements, synkinesis) which are thought to result from misguided collateral branching of regenerating motor axons and reinnervation of inappropriate muscles. Here, we examined whether use of an aorta Y-tube conduit during reconstructive surgery after facial nerve injury reduces synkinesis of orbicularis oris (blink reflex) and vibrissal (whisking) musculature. The abdominal aorta plus its bifurcation was harvested (N = 12) for Y-tube conduits. Animal groups comprised intact animals (Group 1), those receiving hypoglossal-facial nerve end-to-end coaptation alone (HFA; Group 2), and those receiving hypoglossal-facial nerve reconstruction using a Y-tube (HFA-Y-tube, Group 3). Videotape motion analysis at 4 months showed that HFA-Y-tube group showed a reduced synkinesis of eyelid and whisker movements compared to HFA alone. PMID:25574468

  5. Abdominal wall reconstruction with implantable meshes.

    PubMed

    Masden, Derek; Felder, John M; Iorio, Matthew L; Bhanot, Parag; Attinger, Christopher E

    2011-01-01

    Abdominal wall defects present a difficult problem for the reconstructive surgeon. Over the years, numerous implantable materials have becomes available to aid the surgeon in recreating the abdominal wall. This spectrum of implants includes permanent synthetic meshes, absorbable meshes, composite meshes and biomaterials. This review includes the pros and cons for the commercially available abdominal wall implants as well as a review of the literature regarding outcomes for each material. This review will provide the surgeon with current evidence-based information on implantable abdominal materials to be able to make a more informed decision about which implant to use. PMID:21663579

  6. Measuring the activity of a 51Cr neutrino source based on the gamma-radiation spectrum

    NASA Astrophysics Data System (ADS)

    Gorbachev, V. V.; Gavrin, V. N.; Ibragimova, T. V.; Kalikhov, A. V.; Malyshkin, Yu. M.; Shikhin, A. A.

    2015-12-01

    A technique for the measurement of activities of intense β sources by measuring the continuous gamma-radiation (internal bremsstrahlung) spectra is developed. A method for reconstructing the spectrum recorded by a germanium semiconductor detector is described. A method for the absolute measurement of the internal bremsstrahlung spectrum of 51Cr is presented.

  7. Solar total and spectral irradiance reconstruction over last 9000 years

    NASA Astrophysics Data System (ADS)

    Wu, Chi-Ju; Usoskin, Ilya; Krivova, Natalie; Solanki, Sami K.

    2016-07-01

    Although the mechanisms of solar influence on Earth climate system are not yet fully understood, solar total and spectral irradiance are considered to be among the main determinants. Solar total irradiance is the total flux of solar radiative energy entering Earth's climate system, whereas the spectral irradiance describes this energy is distributed over the spectrum. Solar irradiance in the UV band is of special importance since it governs chemical processes in the middle and upper atmosphere. On timescales of the 11-year solar cycle and shorter, solar irradiance is measured by space-based instruments while models are needed to reconstruct solar irradiance on longer timescale. The SATIRE-M model (Spectral And Total Irradiance Reconstruction over millennia) is employed in this study to reconstruct solar irradiance from decadal radionuclide isotope data such as 14C and 10Be stored in tree rings and ice cores, respectively. A reconstruction over the last 9000 years will be presented.

  8. Compressed sensing sparse reconstruction for coherent field imaging

    NASA Astrophysics Data System (ADS)

    Bei, Cao; Xiu-Juan, Luo; Yu, Zhang; Hui, Liu; Ming-Lai, Chen

    2016-04-01

    Return signal processing and reconstruction plays a pivotal role in coherent field imaging, having a significant influence on the quality of the reconstructed image. To reduce the required samples and accelerate the sampling process, we propose a genuine sparse reconstruction scheme based on compressed sensing theory. By analyzing the sparsity of the received signal in the Fourier spectrum domain, we accomplish an effective random projection and then reconstruct the return signal from as little as 10% of traditional samples, finally acquiring the target image precisely. The results of the numerical simulations and practical experiments verify the correctness of the proposed method, providing an efficient processing approach for imaging fast-moving targets in the future. Project supported by the National Natural Science Foundation of China (Grant No. 61505248) and the Fund from Chinese Academy of Sciences, the Light of “Western” Talent Cultivation Plan “Dr. Western Fund Project” (Grant No. Y429621213).

  9. Image reconstruction algorithms with wavelet filtering for optoacoustic imaging

    NASA Astrophysics Data System (ADS)

    Gawali, S.; Leggio, L.; Broadway, C.; González, P.; Sánchez, M.; Rodríguez, S.; Lamela, H.

    2016-03-01

    Optoacoustic imaging (OAI) is a hybrid biomedical imaging modality based on the generation and detection of ultrasound by illuminating the target tissue by laser light. Typically, laser light in visible or near infrared spectrum is used as an excitation source. OAI is based on the implementation of image reconstruction algorithms using the spatial distribution of optical absorption in tissues. In this work, we apply a time-domain back-projection (BP) reconstruction algorithm and a wavelet filtering for point and line detection, respectively. A comparative study between point detection and integrated line detection has been carried out by evaluating their effects on the image reconstructed. Our results demonstrate that the back-projection algorithm proposed is efficient for reconstructing high-resolution images of absorbing spheres embedded in a non-absorbing medium when it is combined with the wavelet filtering.

  10. Coracoclavicular Ligament Reconstruction

    PubMed Central

    Li, Qi; Hsueh, Pei-ling; Chen, Yun-feng

    2014-01-01

    Abstract Operative intervention is recommended for complete acromioclavicular (AC) joint dislocation to restore AC stability, but the best operative technique is still controversial. Twelve fresh-frozen male cadaveric shoulders (average age, 62.8 ± 7.8 years) were equally divided into endobutton versus the modified Weaver-Dunn groups. Each potted scapula and clavicle was fixed in a custom made jig to allow translation and load to failure testing using a Zwick BZ2.5/TS1S material testing machine (Zwick/Roell Co, Germany). A systematic review of 21 studies evaluating reconstructive methods for coracoclavicular or AC joints using a cadaveric model was also performed. From our biomechanical study, after ligament reconstruction, the triple endobutton technique demonstrated superior, anterior, and posterior displacements similar to that of the intact state (P > 0.05). In the modified Weaver-Dunn reconstruction group, however, there was significantly greater anterior (P < 0.001) and posterior (P = 0.003) translation after ligament reconstruction. In addition, there was no significant difference after reconstruction between failure load of the triple endobutton group and that of the intact state (686.88 vs 684.9 N, P > 0.05), whereas the failure load after the modified Weaver-Dunn reconstruction was decreased compared with the intact state (171.64 vs 640.86 N, P < 0.001). From our systematic review of 21 studies, which involved comparison of the modified Weaver-Dunn technique with other methods, the majority showed that the modified Weaver-Dunn procedure had significantly (P < .05) greater laxity than other methods including the endobutton technique. The triple endobutton reconstruction proved superior to the modified Weaver-Dunn technique in restoration of AC joint stability and strength. Triple endobutton reconstruction of the coracoclavicular ligament is superior to the modified Weaver-Dunn reconstruction in controlling both superior and

  11. Primordial power spectrum: a complete analysis with the WMAP nine-year data

    NASA Astrophysics Data System (ADS)

    Hazra, Dhiraj Kumar; Shafieloo, Arman; Souradeep, Tarun

    2013-07-01

    We have improved further the error sensitive Richardson-Lucy deconvolution algorithm making it applicable directly on the un-binned measured angular power spectrum of Cosmic Microwave Background observations to reconstruct the form of the primordial power spectrum. This improvement makes the application of the method significantly more straight forward by removing some intermediate stages of analysis allowing a reconstruction of the primordial spectrum with higher efficiency and precision and with lower computational expenses. Applying the modified algorithm we fit the WMAP 9 year data using the optimized reconstructed form of the primordial spectrum with more than 300 improvement in χ2eff with respect to the best fit power-law. This is clearly beyond the reach of other alternative approaches and reflects the efficiency of the proposed method in the reconstruction process and allow us to look for any possible feature in the primordial spectrum projected in the CMB data. Though the proposed method allow us to look at various possibilities for the form of the primordial spectrum, all having good fit to the data, proper error-analysis is needed to test for consistency of theoretical models since, along with possible physical artefacts, most of the features in the reconstructed spectrum might be arising from fitting noises in the CMB data. Reconstructed error-band for the form of the primordial spectrum using many realizations of the data, all bootstrapped and based on WMAP 9 year data, shows proper consistency of power-law form of the primordial spectrum with the WMAP 9 data at all wave numbers. Including WMAP polarization data in to the analysis have not improved much our results due to its low quality but we expect Planck data will allow us to make a full analysis on CMB observations on both temperature and polarization separately and in combination.

  12. Primordial power spectrum: a complete analysis with the WMAP nine-year data

    SciTech Connect

    Hazra, Dhiraj Kumar; Shafieloo, Arman; Souradeep, Tarun E-mail: arman@apctp.org

    2013-07-01

    We have improved further the error sensitive Richardson-Lucy deconvolution algorithm making it applicable directly on the un-binned measured angular power spectrum of Cosmic Microwave Background observations to reconstruct the form of the primordial power spectrum. This improvement makes the application of the method significantly more straight forward by removing some intermediate stages of analysis allowing a reconstruction of the primordial spectrum with higher efficiency and precision and with lower computational expenses. Applying the modified algorithm we fit the WMAP 9 year data using the optimized reconstructed form of the primordial spectrum with more than 300 improvement in χ{sup 2}{sub eff} with respect to the best fit power-law. This is clearly beyond the reach of other alternative approaches and reflects the efficiency of the proposed method in the reconstruction process and allow us to look for any possible feature in the primordial spectrum projected in the CMB data. Though the proposed method allow us to look at various possibilities for the form of the primordial spectrum, all having good fit to the data, proper error-analysis is needed to test for consistency of theoretical models since, along with possible physical artefacts, most of the features in the reconstructed spectrum might be arising from fitting noises in the CMB data. Reconstructed error-band for the form of the primordial spectrum using many realizations of the data, all bootstrapped and based on WMAP 9 year data, shows proper consistency of power-law form of the primordial spectrum with the WMAP 9 data at all wave numbers. Including WMAP polarization data in to the analysis have not improved much our results due to its low quality but we expect Planck data will allow us to make a full analysis on CMB observations on both temperature and polarization separately and in combination.

  13. Augmented Likelihood Image Reconstruction.

    PubMed

    Stille, Maik; Kleine, Matthias; Hägele, Julian; Barkhausen, Jörg; Buzug, Thorsten M

    2016-01-01

    The presence of high-density objects remains an open problem in medical CT imaging. Data of projections passing through objects of high density, such as metal implants, are dominated by noise and are highly affected by beam hardening and scatter. Reconstructed images become less diagnostically conclusive because of pronounced artifacts that manifest as dark and bright streaks. A new reconstruction algorithm is proposed with the aim to reduce these artifacts by incorporating information about shape and known attenuation coefficients of a metal implant. Image reconstruction is considered as a variational optimization problem. The afore-mentioned prior knowledge is introduced in terms of equality constraints. An augmented Lagrangian approach is adapted in order to minimize the associated log-likelihood function for transmission CT. During iterations, temporally appearing artifacts are reduced with a bilateral filter and new projection values are calculated, which are used later on for the reconstruction. A detailed evaluation in cooperation with radiologists is performed on software and hardware phantoms, as well as on clinically relevant patient data of subjects with various metal implants. Results show that the proposed reconstruction algorithm is able to outperform contemporary metal artifact reduction methods such as normalized metal artifact reduction. PMID:26208310

  14. Consecutive combined response spectrum

    NASA Astrophysics Data System (ADS)

    Xu, Longjun; Zhao, Guochen; Liu, Qingyang; Xie, Yujian; Xie, Lili

    2014-12-01

    Appropriate estimates of earthquake response spectrum are essential for design of new structures, or seismic safety evaluation of existing structures. This paper presents an alternative procedure to construct design spectrum from a combined normalized response spectrum (NRSC) which is obtained from pseudo-velocity spectrum with the ordinate scaled by different peak ground amplitudes (PGA, PGV, PGD) in different period regions. And a consecutive function f( T) used to normalize the ordinates is defined. Based on a comprehensive study of 220 strong ground motions recorded during recent eleven large worldwide earthquakes, the features of the NRSC are discussed and compared with the traditional normalized acceleration, velocity and displacement response spectra (NRSA, NRSV, NRSD). And the relationships between ground amplitudes are evaluated by using a weighted mean method instead of the arithmetic mean. Then the NRSC is used to define the design spectrum with given peak ground amplitudes. At last, the smooth spectrum is compared with those derived by the former approaches, and the accuracy of the proposed spectrum is tested through an analysis of the dispersion of ground motion response spectra.

  15. Current reconstructive management of subglottic stenosis of the larynx with reference to sixty consecutively treated cases.

    PubMed

    Couraud, L; Hafez, A; Velly, J F; Gironnet, I

    1985-10-01

    Sixty patients with subglottic stenosis of acquired and nonneoplastic origin were surgically managed by multiple open procedures. Follow-up ranged from 1 to 10 years. Fifty-seven patients had stable and excellent or good results, 2 of them after further surgery, 1 patient had to live with a retained tracheostomy indefinitely and the remaining 2 patients died. While the whole spectrum of surgical modalities employed in this series may not be recommended with total conviction, the authors express their satisfaction with single resection and end-to-end anastomosis which yields invariably good and rapidly obtainable results (22 cases with complete success). Nevertheless, laryngeal enlargement seems to be essential in the case of upper glottic lesions (19 operations provided 19 successes) while primary resection with moulding plasties may be applicable to complex and extended stenoses (19 operations: 16 successful results and 3 failures). With regard to the choice of operation, the authors emphasize the importance of careful preoperative assessment of the lesions which should assure adequate selection of therapeutic methods according to the degree of associated involvement of the trachea, glottis or supraglottic area. Conservative measures including dilatation, electro-coagulation and laser-beam surgery are considered as palliative only, however, they may be useful either in the course of the patient's preparation or in order to achieve more successful postoperative results. PMID:2416077

  16. Reconstruction of bremsstrahlung spectra from attenuation data using generalized simulated annealing.

    PubMed

    Menin, O H; Martinez, A S; Costa, A M

    2016-05-01

    A generalized simulated annealing algorithm, combined with a suitable smoothing regularization function is used to solve the inverse problem of X-ray spectrum reconstruction from attenuation data. The approach is to set the initial acceptance and visitation temperatures and to standardize the terms of objective function to automate the algorithm to accommodate different spectra ranges. Experiments with both numerical and measured attenuation data are presented. Results show that the algorithm reconstructs spectra shapes accurately. It should be noted that in this algorithm, the regularization function was formulated to guarantee a smooth spectrum, thus, the presented technique does not apply to X-ray spectrum where characteristic radiation are present. PMID:26943902

  17. Adaptive iterative reconstruction

    NASA Astrophysics Data System (ADS)

    Bruder, H.; Raupach, R.; Sunnegardh, J.; Sedlmair, M.; Stierstorfer, K.; Flohr, T.

    2011-03-01

    It is well known that, in CT reconstruction, Maximum A Posteriori (MAP) reconstruction based on a Poisson noise model can be well approximated by Penalized Weighted Least Square (PWLS) minimization based on a data dependent Gaussian noise model. We study minimization of the PWLS objective function using the Gradient Descent (GD) method, and show that if an exact inverse of the forward projector exists, the PWLS GD update equation can be translated into an update equation which entirely operates in the image domain. In case of non-linear regularization and arbitrary noise model this means that a non-linear image filter must exist which solves the optimization problem. In the general case of non-linear regularization and arbitrary noise model, the analytical computation is not trivial and might lead to image filters which are computationally very expensive. We introduce a new iteration scheme in image space, based on a regularization filter with an anisotropic noise model. Basically, this approximates the statistical data weighting and regularization in PWLS reconstruction. If needed, e.g. for compensation of the non-exactness of backprojector, the image-based regularization loop can be preceded by a raw data based loop without regularization and statistical data weighting. We call this combined iterative reconstruction scheme Adaptive Iterative Reconstruction (AIR). It will be shown that in terms of low-contrast visibility, sharpness-to-noise and contrast-to-noise ratio, PWLS and AIR reconstruction are similar to a high degree of accuracy. In clinical images the noise texture of AIR is also superior to the more artificial texture of PWLS.

  18. Upper Eyelid Reconstruction.

    PubMed

    Espinoza, Gabriela Mabel; Prost, Angela Michelle

    2016-05-01

    Reconstruction of the upper eyelid is complicated because the eyelid must retain mobility, flexibility, function, and a suitable mucosal surface over the delicate cornea. Defects of the upper eyelid may be due to congenital defects or traumatic injury or follow oncologic resection. This article focuses on reconstruction due to loss of tissue. Multiple surgeries may be needed to reach the desired results, addressing loss of tissue and then loss of function. Each defect is unique and the laxity and availability of surrounding tissue vary. Knowing the most common techniques for repair assists surgeons in the multifaceted planning that takes place. PMID:27105803

  19. IRIS Spectrum Line Plot

    NASA Video Gallery

    This video shows a line plot of the spectrum. The spectra here are shown for various locations on the Sun. The changes in the movie are caused by differing physical conditions in the locations. Cre...

  20. Fetal Alcohol Spectrum Disorders

    MedlinePlus

    ... alcohol can cause a group of conditions called fetal alcohol spectrum disorders (FASDs). Effects can include physical and behavioral problems such ... alcohol syndrome is the most serious type of FASD. People with fetal alcohol syndrome have facial abnormalities, ...

  1. Quantum Spread Spectrum Communication

    SciTech Connect

    Humble, Travis S

    2010-01-01

    We demonstrate that spectral teleportation can coherently dilate the spectral probability amplitude of a single photon. In preserving the encoded quantum information, this variant of teleportation subsequently enables a form of quantum spread spectrum communication.

  2. Structure-aware Bayesian compressive sensing for frequency-hopping spectrum estimation

    NASA Astrophysics Data System (ADS)

    Liu, Shengheng; Zhang, Yimin D.; Shan, Tao; Qin, Si; Amin, Moeness G.

    2016-05-01

    Frequency-hopping (FH) is one of the commonly used spread spectrum techniques that finds wide applications in communications and radar systems due to its capability of low probability of intercept, reduced interference, and desirable ambiguity property. In this paper, we consider the blind estimation of the instantaneous FH spectrum without the knowledge of hopping patterns. The FH signals are analyzed in the joint time-frequency domain, where FH signals manifest themselves as sparse entries, thus inviting compressive sensing and sparse reconstruction techniques for FH spectrum estimation. In particular, the signals' piecewise-constant frequency characteristics are exploited in the reconstruction of sparse quadratic time-frequency representations. The Bayesian compressive sensing methods are applied to provide high-resolution frequency estimation. The FH spectrum characteristics are used in the design of signal-dependent kernel within the framework of structure-aware sparse reconstruction.

  3. Calibration Requirements for Detecting the 21 cm Epoch of Reionization Power Spectrum and Implications for the SKA

    NASA Astrophysics Data System (ADS)

    Barry, N.; Hazelton, B.; Sullivan, I.; Morales, M. F.; Pober, J. C.

    2016-06-01

    21 cm Epoch of Reionization observations promise to transform our understanding of galaxy formation, but these observations are impossible without unprecedented levels of instrument calibration. We present end-to-end simulations of a full EoR power spectrum analysis including all of the major components of a real data processing pipeline: models of astrophysical foregrounds and EoR signal, frequency-dependent instrument effects, sky-based antenna calibration, and the full PS analysis. This study reveals that traditional sky-based per-frequency antenna calibration can only be implemented in EoR measurement analyses if the calibration model is unrealistically accurate. For reasonable levels of catalogue completeness, the calibration introduces contamination in otherwise foreground-free power spectrum modes, precluding a PS measurement. We explore the origin of this contamination and potential mitigation techniques. We show that there is a strong joint constraint on the precision of the calibration catalogue and the inherent spectral smoothness of antennae, and that this has significant implications for the instrumental design of the SKA and other future EoR observatories.

  4. Reconstructing Community History

    ERIC Educational Resources Information Center

    Shields, Amy

    2004-01-01

    History is alive and well in Lebanon, Missouri. Students in this small town in the southwest region of the state went above and beyond the community's expectations on this special project. This article describes this historical journey which began when students in a summer mural class reconstructed a mural that was originally created by a…

  5. Reconstructing Glaciers on Mars

    NASA Astrophysics Data System (ADS)

    Hubbard, A., II; Brough, S.; Hubbard, B. P.

    2015-12-01

    Mars' mid-latitudes host a substantial volume of ice, equivalent to a ~1 - 2.5 m-thick global layer or the sum of Earth's glaciers and ice caps outside of Antarctica and Greenland. These deposits are the remnants of what is believed to have been a once far larger 'ice age', culminating in a last martian glacial maximum. Despite the identification of >1,300 glacier-like forms (GLFs) - the first order component of Mars' glacial landsystem - in Mars' mid-latitudes, little is known about their composition, dynamics or former extent. Here, we reconstruct the former 3D extent of a well-studied GLF located in eastern Hellas Planitia. We combine high-resolution geomorphic and topographic data, obtained from the High-Resolution Imaging Science Experiment (HiRISE) camera, to reconstruct the GLF's former limits. We then apply a perfect plasticity rheological model, to generate multiple flow-parallel ice-surface transects. These are combined with the GLF's boundary to guide interpolation using ArcGIS' 'Topo to Raster' function to produce a continuous 3D surface for the reconstructed former GLF. Our results indicate that, since its reconstructed 'recent maximum' extent, the GLF's volume has reduced by 0.31 km3 and its area by 6.85 km2, or 70%. On-going research is addressing the degree to which this change is typical of Mars' full GLF population.

  6. Reconstructive Middle Ear Surgery

    PubMed Central

    Ruby, R.R.F.; Ballagh, R.H.

    1992-01-01

    Conductive hearing loss is a common cause of deafness and disability, particularly in children and young adults. This article presents a brief overview of the various methods currently available for reconstructing the tympanic membrane and middle ear ossicular chain, including some comments as to their indications and limitations. Schematic diagrams showing these techniques illustrate the various types of repair described. PMID:21221356

  7. Breast reconstruction - natural tissue

    MedlinePlus

    ... muscle flap; TRAM; Latissimus muscle flap with a breast implant; DIEP flap; DIEAP flap; Gluteal free flap; ... If you are having breast reconstruction at the same time as mastectomy, the surgeon may do either of the following: Skin-sparing mastectomy. This means ...

  8. Reconstructing Playschool Experiences

    ERIC Educational Resources Information Center

    Einarsdottir, Johanna

    2011-01-01

    The current study was conducted with groups of first grade children (aged six years) in two primary schools in Reykjavik in an endeavour to ascertain how they recalled and reconstructed their playschool experiences. The children's playschool teachers were co-researchers participating in the data generation; they were, at the same time participants…

  9. Reconstruction of the auricle

    PubMed Central

    Siegert, Ralf; Magritz, Ralph

    2008-01-01

    Reconstructive and aesthetic surgery of the auricle is one of the most challenging and diverse tasks in plastic head and neck surgery. Injuries, defects and malformations require multiple different techniques, some of which are standardized, other situations require huge experience and artistic creativity. It is a specialty that will never become monotone. PMID:22073078

  10. Reconstructing Progressive Education

    ERIC Educational Resources Information Center

    Kaplan, Andy

    2013-01-01

    The work of Colonel Francis W. Parker, the man whom Dewey called "the father of progressive education," provides a starting point for reconstructing the loose ambiguities of progressive education into a coherent social and educational philosophy. Although progressives have claimed their approach is more humane and sensitive to children, we need…

  11. Stability of climate reconstructions

    NASA Astrophysics Data System (ADS)

    Lohmann, Gerrit; Rimbu, Norel; Wagner, Axel; Dima, Mihai

    2014-05-01

    Reconstruction of climate mode indices using proxy data as predictors is limited due to non-stationarity in atmospheric teleconnections. In this paper a method is presented to identify stable predictors for the reconstruction of the Arctic Oscillation (AO) index. Using the 20th Century reanalysis data, the AO index is calculated for the last 140 years and correlated with global two meter temperature, precipitation, and sea surface temperature anomalies in various moving windows. The stability of the correlation was checked in every point of the global grids. Anomalies from the regions where the correlation of the AO index is stable are used as stable predictors for the AO index. It is shown that the predictors identified through our analysis lead to proper AO reconstructions. Statistical analysis of a global climate simulation covering the last millennium reveals that the stability correlation map of model AO and temperature are very similar to the corresponding observed correlation stability map. It is shown that the stability correlation maps of the AO, as derived from the model, are insensitive to different climate forcing and can be used to systematically select stable predictors for the AO reconstruction during the last millennium and most likely for the late Holocene. Finally, several high resolution proxy data from the stable regions are selected and used for a reconstruction of the AO index during the last three centuries. We argue that selection of proxy data from the stable regions of AO teleconnections leads to a suitable AO reconstruction. Furthermore, the hypothesis of stable teleconnections is tested using atmospheric circulation model experiments. For climate conditions with other ice sheet distributions on the Northern Hemisphere, such as the last glacial maximum climate, considerable changes are detected in the atmospheric variability pattern compared to the present day. Correlation maps of pseudo proxy records over Europe, the Red Sea area, and

  12. Comparison of spread spectrum and pulse signal excitation for split spectrum techniques composite imaging

    NASA Astrophysics Data System (ADS)

    Svilainis, L.; Kitov, S.; Rodríguez, A.; Vergara, L.; Dumbrava, V.; Chaziachmetovas, A.

    2012-12-01

    Ultrasonic imaging of composites was investigated. Glass and carbon fiber reinforced plastic produced by resin transfer molding and prepreg forming were analyzed. In some of the samples air bubbles were trapped during RTM (resin transfer molding) process and interlayer gaps were present in prepreg technology samples. One of the most expected techniques to apply in such case is the Split Spectrum processing. On the other hand such signals require specific processing to reliably reconstruct the temporal position of the defect reflection. Correlation processing can be used for signal compression or Wiener filtering can be applied for spectral content equalisation. Pulse signals are simple to generate, but lack the possibility to alter the signal's spectrum shape. Spread spectrum signals offer a powerful tool for signal energy over frequency band increase and resolution enhancement. CW (continuous wave) burst has high energy but lacks the bandwidth needed for SSP (spread spectrum processing). The aim of the investigation was to compare the performance of the above signals in case of composite imaging, when various Split Spectrum Processing techniques are used with preceding Wiener processing for spectral content compensation. Resulting composite signals and images obtained are presented. Structural noise removal performance was evaluated as Receiver Operating Characteristics (ROC).

  13. Preparing for Breast Reconstruction Surgery

    MedlinePlus

    ... after breast reconstruction surgery Preparing for breast reconstruction surgery Your surgeon can help you know what to ... The plan for follow-up Costs Understanding your surgery costs Health insurance policies often cover most or ...

  14. Controversies in Parotid Defect Reconstruction.

    PubMed

    Tamplen, Matthew; Knott, P Daniel; Fritz, Michael A; Seth, Rahul

    2016-08-01

    Reconstruction of the parotid defect is a complex topic that encompasses restoration of both facial form and function. The reconstructive surgeon must consider facial contour, avoidance of Frey syndrome, skin coverage, tumor surveillance, potential adjuvant therapy, and facial reanimation when addressing parotid defects. With each defect there are several options within the reconstructive ladder, creating controversies regarding optimal management. This article describes surgical approaches to reconstruction of parotid defects, highlighting areas of controversy. PMID:27400838

  15. Micro acoustic spectrum analyzer

    DOEpatents

    Schubert, W. Kent; Butler, Michael A.; Adkins, Douglas R.; Anderson, Larry F.

    2004-11-23

    A micro acoustic spectrum analyzer for determining the frequency components of a fluctuating sound signal comprises a microphone to pick up the fluctuating sound signal and produce an alternating current electrical signal; at least one microfabricated resonator, each resonator having a different resonant frequency, that vibrate in response to the alternating current electrical signal; and at least one detector to detect the vibration of the microfabricated resonators. The micro acoustic spectrum analyzer can further comprise a mixer to mix a reference signal with the alternating current electrical signal from the microphone to shift the frequency spectrum to a frequency range that is a better matched to the resonant frequencies of the microfabricated resonators. The micro acoustic spectrum analyzer can be designed specifically for portability, size, cost, accuracy, speed, power requirements, and use in a harsh environment. The micro acoustic spectrum analyzer is particularly suited for applications where size, accessibility, and power requirements are limited, such as the monitoring of industrial equipment and processes, detection of security intrusions, or evaluation of military threats.

  16. Action spectrum for photocarcinogenesis.

    PubMed

    de Gruijl, F R

    1995-01-01

    The wavelength dependence of the carcinogenicity of ultraviolet (UV) radiation needs to be known in order to assess the carcinogenic risks of various UV sources, most notably the different solar UV spectra at ground level under depleting stratospheric ozone. This wavelength dependence cannot be extracted from human data (e.g., from epidemiology); it can, however, be directly obtained from animal experiments. Precise information on the wavelength dependence, the so-called action spectrum, was not available until recently: erythemal or mutagenic action spectra have been used as substitutes. However, experimental data on skin tumors induced in hairless mice (Skh:HR1) with various polychromatic sources have been building up. Our group has found that none of the substitute action spectra yield a statistically acceptable description of our data, and we have, therefore, derived a new action spectrum, dubbed the SCUP action spectrum (SCUP stands for Skin Cancer Utrecht-Philadelphia, because the action spectrum also fits experimental data from the former Skin and Cancer Hospital in Philadelphia). The SCUP action spectrum has a maximum at 293 nm, and in the UVA region above 340 nm the relative carcinogenicity per J/m2 drops to about 10(-4) of this maximum. The effects of an ozone depletion on solar UV doses weighted with these different action spectra are compared: the erythemal and SCUP weighted dose come out as least sensitive with a 1.3% and 1.4% increase, respectively, for every 1% decrease in ozone. PMID:7597292

  17. Unilateral Multiple Facial Nerve Branch Reconstruction Using “End-to-side Loop Graft” Supercharged by Hypoglossal Nerve

    PubMed Central

    Sasaki, Ryo; Takeuchi, Yuichi; Watanabe, Yorikatsu; Niimi, Yosuke; Sakurai, Hiroyuki; Miyata, Mariko; Yamato, Masayuki

    2014-01-01

    Background: Extensive facial nerve defects between the facial nerve trunk and its branches can be clinically reconstructed by incorporating double innervation into an end-to-side loop graft technique. This study developed a new animal model to evaluate the technique’s ability to promote nerve regeneration. Methods: Rats were divided into the intact, nonsupercharge, and supercharge groups. Artificially created facial nerve defects were reconstructed with a nerve graft, which was end-to-end sutured from proximal facial nerve stump to the mandibular branch (nonsupercharge group), or with the graft of which other end was end-to-side sutured to the hypoglossal nerve (supercharge group). And they were evaluated after 30 weeks. Results: Axonal diameter was significantly larger in the supercharge group than in the nonsupercharge group for the buccal (3.78 ± 1.68 vs 3.16 ± 1.22; P < 0.0001) and marginal mandibular branches (3.97 ± 2.31 vs 3.46 ± 1.57; P < 0.0001), but the diameter was significantly larger in the intact group for all branches except the temporal branch. In the supercharge group, compound muscle action potential amplitude was significantly higher than in the nonsupercharge group (4.18 ± 1.49 mV vs 1.87 ± 0.37 mV; P < 0.0001) and similar to that in the intact group (4.11 ± 0.68 mV). Retrograde labeling showed that the mimetic muscles were double-innervated by facial and hypoglossal nerve nuclei in the supercharge group. Conclusions: Multiple facial nerve branch reconstruction with an end-to-side loop graft was able to achieve axonal distribution. Additionally, axonal supercharge from the hypoglossal nerve significantly improved outcomes. PMID:25426357

  18. Algebraic reconstruction techniques for spectral reconstruction in diffuse optical tomography

    SciTech Connect

    Brendel, Bernhard; Ziegler, Ronny; Nielsen, Tim

    2008-12-01

    Reconstruction in diffuse optical tomography (DOT) necessitates solving the diffusion equation, which is nonlinear with respect to the parameters that have to be reconstructed. Currently applied solving methods are based on the linearization of the equation. For spectral three-dimensional reconstruction, the emerging equation system is too large for direct inversion, but the application of iterative methods is feasible. Computational effort and speed of convergence of these iterative methods are crucial since they determine the computation time of the reconstruction. In this paper, the iterative methods algebraic reconstruction technique (ART) and conjugated gradients (CGs) as well as a new modified ART method are investigated for spectral DOT reconstruction. The aim of the modified ART scheme is to speed up the convergence by considering the specific conditions of spectral reconstruction. As a result, it converges much faster to favorable results than conventional ART and CG methods.

  19. Broad spectrum solar cell

    DOEpatents

    Walukiewicz, Wladyslaw; Yu, Kin Man; Wu, Junqiao; Schaff, William J.

    2007-05-15

    An alloy having a large band gap range is used in a multijunction solar cell to enhance utilization of the solar energy spectrum. In one embodiment, the alloy is In.sub.1-xGa.sub.xN having an energy bandgap range of approximately 0.7 eV to 3.4 eV, providing a good match to the solar energy spectrum. Multiple junctions having different bandgaps are stacked to form a solar cell. Each junction may have different bandgaps (realized by varying the alloy composition), and therefore be responsive to different parts of the spectrum. The junctions are stacked in such a manner that some bands of light pass through upper junctions to lower junctions that are responsive to such bands.

  20. Reconstruction of signals with unknown spectra in information field theory with parameter uncertainty

    SciTech Connect

    Ensslin, Torsten A.; Frommert, Mona

    2011-05-15

    The optimal reconstruction of cosmic metric perturbations and other signals requires knowledge of their power spectra and other parameters. If these are not known a priori, they have to be measured simultaneously from the same data used for the signal reconstruction. We formulate the general problem of signal inference in the presence of unknown parameters within the framework of information field theory. To solve this, we develop a generic parameter-uncertainty renormalized estimation (PURE) technique. As a concrete application, we address the problem of reconstructing Gaussian signals with unknown power-spectrum with five different approaches: (i) separate maximum-a-posteriori power-spectrum measurement and subsequent reconstruction, (ii) maximum-a-posteriori reconstruction with marginalized power-spectrum, (iii) maximizing the joint posterior of signal and spectrum, (iv) guessing the spectrum from the variance in the Wiener-filter map, and (v) renormalization flow analysis of the field-theoretical problem providing the PURE filter. In all cases, the reconstruction can be described or approximated as Wiener-filter operations with assumed signal spectra derived from the data according to the same recipe, but with differing coefficients. All of these filters, except the renormalized one, exhibit a perception threshold in case of a Jeffreys prior for the unknown spectrum. Data modes with variance below this threshold do not affect the signal reconstruction at all. Filter (iv) seems to be similar to the so-called Karhune-Loeve and Feldman-Kaiser-Peacock estimators for galaxy power spectra used in cosmology, which therefore should also exhibit a marginal perception threshold if correctly implemented. We present statistical performance tests and show that the PURE filter is superior to the others, especially if the post-Wiener-filter corrections are included or in case an additional scale-independent spectral smoothness prior can be adopted.

  1. Spectral reconstruction by scatter analysis for a linear accelerator photon beam.

    PubMed

    Jalbout, Wassim T; Spyrou, Nicholas M

    2006-05-01

    Pre-existing methods for photon beam spectral reconstruction are briefly reviewed. An alternative reconstruction method by scatter analysis for linear accelerators is introduced. The method consists in irradiating a small plastic phantom at standard 100 cm SSD and inferring primary beam energy spectral information based on the measurement with a standard Farmer chamber of scatter around the phantom at several specific scatter angles: a scatter curve is measured which is indicative of the primary spectrum at hand. A Monte Carlo code is used to simulate the scatter measurement set-up and predict the relative magnitude of scatter measurements for mono-energetic primary beams. Based on mono-energetic primary scatter data, measured scatter curves are analysed and the spectrum unfolded as the sum of mono-energetic individual energy bins using the Schiff bremsstrahlung model. The method is applied to an Elekta/SL18 6 MV photon beam. The reconstructed spectrum matches the Monte Carlo calculated spectrum for the same beam within 6.2% (average error when spectra are compared bin by bin). Depth dose values calculated for the reconstructed spectrum agree with physically measured depth dose data to within 1%. Scatter analysis is preliminarily shown to have potential as a practical spectral reconstruction method requiring few measurements under standard 100 cm SSD and feasible in any radiotherapy department using a phantom and a Farmer chamber. PMID:16625037

  2. Stochastic reconstruction of sandstones

    PubMed

    Manwart; Torquato; Hilfer

    2000-07-01

    A simulated annealing algorithm is employed to generate a stochastic model for a Berea sandstone and a Fontainebleau sandstone, with each a prescribed two-point probability function, lineal-path function, and "pore size" distribution function, respectively. We find that the temperature decrease of the annealing has to be rather quick to yield isotropic and percolating configurations. A comparison of simple morphological quantities indicates good agreement between the reconstructions and the original sandstones. Also, the mean survival time of a random walker in the pore space is reproduced with good accuracy. However, a more detailed investigation by means of local porosity theory shows that there may be significant differences of the geometrical connectivity between the reconstructed and the experimental samples. PMID:11088546

  3. NREL Spectrum of Innovation

    ScienceCinema

    None

    2013-05-29

    There are many voices calling for a future of abundant clean energy. The choices are difficult and the challenges daunting. How will we get there? The National Renewable Energy Laboratory integrates the entire spectrum of innovation including fundamental science, market relevant research, systems integration, testing and validation, commercialization and deployment. The innovation process at NREL is interdependent and iterative. Many scientific breakthroughs begin in our own laboratories, but new ideas and technologies come to NREL at any point along the innovation spectrum to be validated and refined for commercial use.

  4. Bottomonium spectrum revisited

    NASA Astrophysics Data System (ADS)

    Segovia, Jorge; Ortega, Pablo G.; Entem, David R.; Fernández, Francisco

    2016-04-01

    We revisit the bottomonium spectrum motivated by the recently exciting experimental progress in the observation of new bottomonium states, both conventional and unconventional. Our framework is a nonrelativistic constituent quark model which has been applied to a wide range of hadronic observables from the light to the heavy quark sector, and thus the model parameters are completely constrained. Beyond the spectrum, we provide a large number of electromagnetic, strong and hadronic decays in order to discuss the quark content of the bottomonium states and give more insights about a better way to determine their properties experimentally.

  5. Improving VHF Spectrum Utilization

    NASA Technical Reports Server (NTRS)

    Andro, Monty; Orr, Richard; Foore, Larry; Sheehe, Charles; Freeman, Mark; Nguyen, Thanh; Bretmersky, Steven; Laberge, Chuck; Buchanan, David

    2004-01-01

    Limited VHF communications system capacity and increasing air traffic results in congestion of the aviation VHF spectrum. The voice communications errors and delayed channel access create system congestion and air traffic delays. Regulatory subdivision of bands for specific functions limits flexibility in the frequency usage. The objective of this viewgraph presentation is to identify near/mid/far term technologies to improve the performance and spectrum efficiency of current and emerging VHF communications systems. Select technologies with the highest potential, perform research and development to bring them to implementation stage.

  6. LOFAR sparse image reconstruction

    NASA Astrophysics Data System (ADS)

    Garsden, H.; Girard, J. N.; Starck, J. L.; Corbel, S.; Tasse, C.; Woiselle, A.; McKean, J. P.; van Amesfoort, A. S.; Anderson, J.; Avruch, I. M.; Beck, R.; Bentum, M. J.; Best, P.; Breitling, F.; Broderick, J.; Brüggen, M.; Butcher, H. R.; Ciardi, B.; de Gasperin, F.; de Geus, E.; de Vos, M.; Duscha, S.; Eislöffel, J.; Engels, D.; Falcke, H.; Fallows, R. A.; Fender, R.; Ferrari, C.; Frieswijk, W.; Garrett, M. A.; Grießmeier, J.; Gunst, A. W.; Hassall, T. E.; Heald, G.; Hoeft, M.; Hörandel, J.; van der Horst, A.; Juette, E.; Karastergiou, A.; Kondratiev, V. I.; Kramer, M.; Kuniyoshi, M.; Kuper, G.; Mann, G.; Markoff, S.; McFadden, R.; McKay-Bukowski, D.; Mulcahy, D. D.; Munk, H.; Norden, M. J.; Orru, E.; Paas, H.; Pandey-Pommier, M.; Pandey, V. N.; Pietka, G.; Pizzo, R.; Polatidis, A. G.; Renting, A.; Röttgering, H.; Rowlinson, A.; Schwarz, D.; Sluman, J.; Smirnov, O.; Stappers, B. W.; Steinmetz, M.; Stewart, A.; Swinbank, J.; Tagger, M.; Tang, Y.; Tasse, C.; Thoudam, S.; Toribio, C.; Vermeulen, R.; Vocks, C.; van Weeren, R. J.; Wijnholds, S. J.; Wise, M. W.; Wucknitz, O.; Yatawatta, S.; Zarka, P.; Zensus, A.

    2015-03-01

    Context. The LOw Frequency ARray (LOFAR) radio telescope is a giant digital phased array interferometer with multiple antennas distributed in Europe. It provides discrete sets of Fourier components of the sky brightness. Recovering the original brightness distribution with aperture synthesis forms an inverse problem that can be solved by various deconvolution and minimization methods. Aims: Recent papers have established a clear link between the discrete nature of radio interferometry measurement and the "compressed sensing" (CS) theory, which supports sparse reconstruction methods to form an image from the measured visibilities. Empowered by proximal theory, CS offers a sound framework for efficient global minimization and sparse data representation using fast algorithms. Combined with instrumental direction-dependent effects (DDE) in the scope of a real instrument, we developed and validated a new method based on this framework. Methods: We implemented a sparse reconstruction method in the standard LOFAR imaging tool and compared the photometric and resolution performance of this new imager with that of CLEAN-based methods (CLEAN and MS-CLEAN) with simulated and real LOFAR data. Results: We show that i) sparse reconstruction performs as well as CLEAN in recovering the flux of point sources; ii) performs much better on extended objects (the root mean square error is reduced by a factor of up to 10); and iii) provides a solution with an effective angular resolution 2-3 times better than the CLEAN images. Conclusions: Sparse recovery gives a correct photometry on high dynamic and wide-field images and improved realistic structures of extended sources (of simulated and real LOFAR datasets). This sparse reconstruction method is compatible with modern interferometric imagers that handle DDE corrections (A- and W-projections) required for current and future instruments such as LOFAR and SKA.

  7. Reconstruction of vaginal agenesis.

    PubMed

    Ozkan, Ozlenen; Erman Akar, Münire; Ozkan, Omer; Doğan, N Utku

    2011-06-01

    Vaginal ageneses are by no means rare anomalies. Complete Mullerian agenesis is the most common reason for vaginal agenesis requiring reconstruction. Patients usually present with pain, hematocolpos, or hematometra in puberty, and later with amenorrhea and dyspareunia. Detailed information is given here regarding etiologies, timing of surgery, and current treatment options for vaginal agenesis. Outcomes and short- and long-term complications of recent treatment options are also discussed. PMID:21372677

  8. [Reconstruction of pulpectomized teeth].

    PubMed

    Colon, P; Picard, B

    1990-04-01

    The general principles governing the choice of materials for reconstruction of devitalized teeth are determined on the basis of mechanical and biological imperatives as well as degradation phenomena. In describing the various techniques for clinical implementation, particular emphasis is placed on the imperatives and limitations of each protocol. A decisive factor in the durability of restorations is their homogeneity, as well as the clinical conditions under which they are performed. PMID:2135782

  9. Secondary femoropopliteal reconstruction.

    PubMed Central

    Whittemore, A D; Clowes, A W; Couch, N P; Mannick, J A

    1981-01-01

    Retrospective analysis of the authors' experience with 109 primary femoropopliteal bypass vein grafts that failed allows description of three distinct modes of failure. Within 30 days of surgery, failure resulted primarily from technical or judgmental errors. The development of stenotic lesions within the vein graft caused a second group of failures during the first year after bypass. The third group most commonly failed due to progression of peripheral atherosclerosis a year or more following original bypass. No correlation was found, however, between the mode of failure and results of secondary femoropopliteal-tibial reconstruction, which yielded an overall 50% five-year cumulative limb salvage rate. The results indicate that this salvage rate can be anticipated regardless of the number of secondary operations required. The highest long-term patency rate was achieved when frequent postoperative follow-up examinations allowed recognition of graft failure prior to total occlusion. Under such circumstances a simple vein patch of stenotic lesions yielded an 85% five-year graft patency. Following actual thrombosis, however, the highest five-year patency rate was achieved when reconstruction was performed using a new vein graft; saphenous vein and arm vein were equally effective. When prosthetic material was used, no secondary graft remained patent beyond three years. Finally, when a proximal or distal portion of the original vein graft proved adequate in caliber following thrombectomy, it could be successfully incorporated in a secondary reconstruction with the expectation of a 50% five-year limb salvage rate. No statistically significant difference was found in salvage rates among each of the patient groups representing the three common modes of graft failure. This finding, coupled with an acceptable 2.5% operative mortality rate, provides justification for an aggressive approach toward secondary femoropopliteal reconstruction. Images Fig. 1a. Fig. 1c. PMID:7458449

  10. Kinky tomographic reconstruction

    SciTech Connect

    Hanson, K.M.; Cunningham, G.S.; Bilisoly, R.L.

    1996-05-01

    We address the issue of how to make decisions about the degree of smoothness demanded of a flexible contour used to model the boundary of a 2D object. We demonstrate the use of a Bayesian approach to set the strength of the smoothness prior for a tomographic reconstruction problem. The Akaike Information Criterion is used to determine whether to allow a kink in the contour.

  11. Paleoproductivity Reconstructions Using Radiolarians

    NASA Astrophysics Data System (ADS)

    Lazarus, D. B.

    2003-12-01

    This talk reviews the use of radiolarian assemblages in paleoproductivity reconstruction. Molina-Cruz and CLIMAP co-workers first identified a distinct radiolarian assemblage whose modern geographic distribution closely matched that of an upwelling region (eastern Pacific Peru-Chile). Nigrini and Caulet subsequently identified additional species largely endemic to various upwelling environments. They applied this in the form of an Upwelling Radiolarian Index (URI) in down-core studies of upwelling history. Recently, Jacot des Combes and Weinheimer have used published distributions of living radiolarians in the water-column to assign fossil taxa to surface vs subsurface groups. They used ratios of thermocline to surface taxa (e.g., the Thermocline to Surface Radiolarian Index, or TSRI), which measures relative enhancement of thermocline to surface radiolarian production in regions of upwelling, to reconstruct past ocean productivity. Both methods appear to perform well, although neither is always reliable. Both the URI and TSRI methods are based on a small number of taxa (ca. 10 each), although biogeographic and water depth information are now available for ca. 100 living species. The use of additional taxa should make reconstructions more robust by reducing the effects of single species ecology, and making index values less sensitive to evolutionary changes in taxa over Neogene time intervals. Taxonomic assemblage reconstructions of productivity have some inherent advantages over bulk flux proxies, being less sensitive to preservation problems or the age model employed. Radiolarian assemblages are particularly useful in upwelling regions where carbonate fossils are poorly preserved. All are however limited by our sparse knowledge of the ecology of the various species used. Among the major microfossil groups, radiolarian ecology and biology are in particular relatively poorly known; even the descriptive taxonomy of living species is not yet complete. Despite these

  12. Validation of measurement-guided 3D VMAT dose reconstruction on a heterogeneous anthropomorphic phantom.

    PubMed

    Opp, Daniel; Nelms, Benjamin E; Zhang, Geoffrey; Stevens, Craig; Feygelman, Vladimir

    2013-01-01

    3DVH software (Sun Nuclear Corp., Melbourne, FL) is capable of generating a volumetric patient VMAT dose by applying a volumetric perturbation algorithm based on comparing measurement-guided dose reconstruction and TPS-calculated dose to a cylindrical phantom. The primary purpose of this paper is to validate this dose reconstruction on an anthropomorphic heterogeneous thoracic phantom by direct comparison to independent measurements. The dosimetric insert to the phantom is novel, and thus the secondary goal is to demonstrate how it can be used for the hidden target end-to-end testing of VMAT treatments in lung. A dosimetric insert contains a 4 cm diameter unit-density spherical target located inside the right lung (0.21 g/cm(3) density). It has 26 slots arranged in two orthogonal directions, milled to hold optically stimulated luminescent dosimeters (OSLDs). Dose profiles in three cardinal orthogonal directions were obtained for five VMAT plans with varying degrees of modulation. After appropriate OSLD corrections were applied, 3DVH measurement-guided VMAT dose reconstruction agreed 100% with the measurements in the unit density target sphere at 3%/3 mm level (composite analysis) for all profile points for the four less-modulated VMAT plans, and for 96% of the points in the highly modulated C-shape plan (from TG-119). For this latter plan, while 3DVH shows acceptable agreement with independent measurements in the unit density target, in the lung disagreement with experiment is relatively high for both the TPS calculation and 3DVH reconstruction. For the four plans excluding the C-shape, 3%/3 mm overall composite analysis passing rates for 3DVH against independent measurement ranged from 93% to 100%. The C-shape plan was deliberately chosen as a stress test of the algorithm. The dosimetric spatial alignment hidden target test demonstrated the average distance to agreement between the measured and TPS profiles in the steep dose gradient area at the edge of the 2 cm

  13. Bayesian image reconstruction in astronomy

    NASA Astrophysics Data System (ADS)

    Nunez, Jorge; Llacer, Jorge

    1990-09-01

    This paper presents the development and testing of a new iterative reconstruction algorithm for astronomy. A maximum a posteriori method of image reconstruction in the Bayesian statistical framework is proposed for the Poisson-noise case. The method uses the entropy with an adjustable 'sharpness parameter' to define the prior probability and the likelihood with 'data increment' parameters to define the conditional probability. The method makes it possible to obtain reconstructions with neither the problem of the 'grey' reconstructions associated with the pure Bayesian reconstructions nor the problem of image deterioration, typical of the maximum-likelihood method. The present iterative algorithm is fast and stable, maintains positivity, and converges to feasible images.

  14. Regularized image reconstruction for continuously self-imaging gratings.

    PubMed

    Horisaki, Ryoichi; Piponnier, Martin; Druart, Guillaume; Guérineau, Nicolas; Primot, Jérôme; Goudail, François; Taboury, Jean; Tanida, Jun

    2013-06-01

    In this paper, we demonstrate two image reconstruction schemes for continuously self-imaging gratings (CSIGs). CSIGs are diffractive optical elements that generate a depth-invariant propagation pattern and sample objects with a sparse spatial frequency spectrum. To compensate for the sparse sampling, we apply two methods with different regularizations for CSIG imaging. The first method employs continuity of the spatial frequency spectrum, and the second one uses sparsity of the intensity pattern. The two methods are demonstrated with simulations and experiments. PMID:23736336

  15. Fractal Plate Reconstructions, Incorporating Asymmetric Spreading and Kinematics

    NASA Astrophysics Data System (ADS)

    Pilger, R.

    2011-12-01

    Accretionary plate boundaries - spreading centers and associated transform faults - possess fractal structure like coastlines. Their apparent length demonstrates self-similarity over a range of scales, maximizing multiplicity (entropy) in a recursive chaotic process. Further, optimal, combined oceanic plate reconstructions, incorporating asymmetric accretion over a range of ages produce fractal structure. The minimum fractal configuration as a function of the reconstruction parameters approximates the Lagrangian constraint (the information) in the maximum entropy formalism. The optimal fractal spectrum itself represents maximum entropy of the reconstructed data describing the spreading center for the preferred rotation parameters. Because fractals are intrinsically discontinuous (and analytic derivatives are unavailable), conventional non-linear least squares approaches are inapplicable. Instead, derivative-free, iterative conjugate gradient and simplex algorithms are utilized. In order to allow for kinematic calculations and integrated reconstructions of diverse data ages, parameters are spline-interpolated, rate-normalized, pseudo-vectors. The new formalism provides a unique fitting criterion and algorithm for simultaneous plate and spreading-center reconstruction and kinematics. It also provides a fractal template for reconstructions of other tectonic types.

  16. Spin-polarized gapped Dirac spectrum of unsupported silicene

    NASA Astrophysics Data System (ADS)

    Podsiadły-Paszkowska, A.; Krawiec, M.

    2016-06-01

    We study effects of the spin-orbit interaction and the atomic reconstruction of silicene on its electronic spectrum. As an example we consider unsupported silicene pulled off from Pb(111) substrate. Using first principles density functional theory we show that the inversion symmetry broken arrangement of atoms and the spin-orbit interaction generate a spin-polarized electronic spectrum with an energy gap in the Dirac cone. These findings are particularly interesting in view of the quantum anomalous and quantum valley Hall effects and should be observable in weakly interacting silicene-substrate systems.

  17. "Mini-Flow-Through" Deep Inferior Epigastric Perforator Flap for Breast Reconstruction with Preservation of Both Internal Mammary and Deep Inferior Epigastric Vessels

    PubMed Central

    Sugawara, Jun; Yasumura, Kazunori; Mikami, Taro; Kobayashi, Shinji; Maegawa, Jiro

    2015-01-01

    This procedure was developed for preservation of the rectus muscle components and deep inferior epigastric vessel after deep inferior epigastric perforator (DIEP) flap harvesting. A 53-year-old woman with granuloma caused by silicone injection underwent bilateral nipple-sparing mastectomies and immediate reconstruction with "mini-flow-through" DIEP flaps. The flaps were dissected based on the single largest perforator with a short segment of the lateral branch of the deep inferior epigastric vessel that was transected as a free flap for breast reconstruction. The short segments of the donor deep inferior epigastric vessel branch are primarily end-to-end anastomosed to each other. A short T-shaped pedicle mini-flow-through DIEP flap is interposed in the incised recipient's internal mammary vessels with two arterial and four concomitant venous anastomoses. Although it requires multiple vascular anastomoses and a short pedicle for the flap setting, the mini-flow-through DIEP flap provides a large pedicle caliber, enabling safer microsurgical anastomosis and well-vascularized tissue for creating a natural breast without consuming time or compromising the rectus muscle components and vascular flow of both the deep inferior epigastric and internal mammary vessels. PMID:26618128

  18. Enhancement of low-quality reconstructed digital hologram images based on frequency extrapolation of large objects under the diffraction limit

    NASA Astrophysics Data System (ADS)

    Liu, Ning; Li, Weiliang; Zhao, Dongxue

    2016-03-01

    During the reconstruction of a digital hologram, the reconstructed image is usually degraded by speckle noise, which makes it hard to observe the original object pattern. In this paper, a new reconstructed image enhancement method is proposed, which first reduces the speckle noise using an adaptive Gaussian filter, then calculates the high frequencies that belong to the object pattern based on a frequency extrapolation strategy. The proposed frequency extrapolation first calculates the frequency spectrum of the Fourier-filtered image, which is originally reconstructed from the +1 order of the hologram, and then gives the initial parameters for an iterative solution. The analytic iteration is implemented by continuous gradient threshold convergence to estimate the image level and vertical gradient information. The predicted spectrum is acquired through the analytical iteration of the original spectrum and gradient spectrum analysis. Finally, the reconstructed spectrum of the restoration image is acquired from the synthetic correction of the original spectrum using the predicted gradient spectrum. We conducted our experiment very close to the diffraction limit and used low-quality equipment to prove the feasibility of our method. Detailed analysis and figure demonstrations are presented in the paper.

  19. Enhancement of low-quality reconstructed digital hologram images based on frequency extrapolation of large objects under the diffraction limit

    NASA Astrophysics Data System (ADS)

    Liu, Ning; Li, Weiliang; Zhao, Dongxue

    2016-06-01

    During the reconstruction of a digital hologram, the reconstructed image is usually degraded by speckle noise, which makes it hard to observe the original object pattern. In this paper, a new reconstructed image enhancement method is proposed, which first reduces the speckle noise using an adaptive Gaussian filter, then calculates the high frequencies that belong to the object pattern based on a frequency extrapolation strategy. The proposed frequency extrapolation first calculates the frequency spectrum of the Fourier-filtered image, which is originally reconstructed from the +1 order of the hologram, and then gives the initial parameters for an iterative solution. The analytic iteration is implemented by continuous gradient threshold convergence to estimate the image level and vertical gradient information. The predicted spectrum is acquired through the analytical iteration of the original spectrum and gradient spectrum analysis. Finally, the reconstructed spectrum of the restoration image is acquired from the synthetic correction of the original spectrum using the predicted gradient spectrum. We conducted our experiment very close to the diffraction limit and used low-quality equipment to prove the feasibility of our method. Detailed analysis and figure demonstrations are presented in the paper.

  20. The Frequency Spectrum Radio.

    ERIC Educational Resources Information Center

    Howkins, John, Ed.

    1979-01-01

    This journal issue focuses on the frequency spectrum used in radio communication and on the World Administrative Radio Conference, sponsored by the International Telecommunication Union, held in Geneva, Switzerland, in the fall of 1979. Articles describe the World Administrative Radio Conference as the most important radio communication conference…