Evaluation of RSA set-up from a clinical biplane fluoroscopy system for 3D joint kinematic analysis.

PubMed

Bonanzinga, Tommaso; Signorelli, Cecilia; Bontempi, Marco; Russo, Alessandro; Zaffagnini, Stefano; Marcacci, Maurilio; Bragonzoni, Laura

2016-01-01

dinamic roentgen stereophotogrammetric analysis (RSA), a technique currently based only on customized radiographic equipment, has been shown to be a very accurate method for detecting three-dimensional (3D) joint motion. The aim of the present work was to evaluate the applicability of an innovative RSA set-up for in vivo knee kinematic analysis, using a biplane fluoroscopic image system. To this end, the Authors describe the set-up as well as a possible protocol for clinical knee joint evaluation. The accuracy of the kinematic measurements is assessed. the Authors evaluated the accuracy of 3D kinematic analysis of the knee in a new RSA set-up, based on a commercial biplane fluoroscopy system integrated into the clinical environment. The study was organized in three main phases: an in vitro test under static conditions, an in vitro test under dynamic conditions reproducing a flexion-extension range of motion (ROM), and an in vivo analysis of the flexion-extension ROM. For each test, the following were calculated, as an indication of the tracking accuracy: mean, minimum, maximum values and standard deviation of the error of rigid body fitting. in terms of rigid body fitting, in vivo test errors were found to be 0.10±0.05 mm. Phantom tests in static and kinematic conditions showed precision levels, for translations and rotations, of below 0.1 mm/0.2° and below 0.5 mm/0.3° respectively for all directions. the results of this study suggest that kinematic RSA can be successfully performed using a standard clinical biplane fluoroscopy system for the acquisition of slow movements of the lower limb. a kinematic RSA set-up using a clinical biplane fluoroscopy system is potentially applicable and provides a useful method for obtaining better characterization of joint biomechanics.

The Recommendations for Linear Measurement Techniques on the Measurements of Nonlinear System Parameters of a Joint.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, Scott A; Catalfamo, Simone; Brake, Matthew R. W.

2017-01-01

In the study of the dynamics of nonlinear systems, experimental measurements often convolute the response of the nonlinearity of interest and the effects of the experimental setup. To reduce the influence of the experimental setup on the deduction of the parameters of the nonlinearity, the response of a mechanical joint is investigated under various experimental setups. These experiments first focus on quantifying how support structures and measurement techniques affect the natural frequency and damping of a linear system. The results indicate that support structures created from bungees have negligible influence on the system in terms of frequency and damping ratiomore » variations. The study then focuses on the effects of the excitation technique on the response for a linear system. The findings suggest that thinner stingers should not be used, because under the high force requirements the stinger bending modes are excited adding unwanted torsional coupling. The optimal configuration for testing the linear system is then applied to a nonlinear system in order to assess the robustness of the test configuration. Finally, recommendations are made for conducting experiments on nonlinear systems using conventional/linear testing techniques.« less

Coherent properties of ultraweak photon emission from biological system and its application in medicine

NASA Astrophysics Data System (ADS)

Zhu, Yanbin; Ma, Junfu; Guo, Zhouyi

2001-10-01

In the paper the research status and viewpoints about the coherent of the ultra-weak photon emission from biological system (UPE) were simply introduced. For proving the biophotons indeed have coherent from another side, an experimental setup for testing UPE in different spectral region was designed. Using the experimental setup the test data of different several spectral regions from 300nm to 1060nm has been got. These test results show that UPE of living biological system exists in wide spectra region from UV-visible to infrared. Using the test data, we also can obtain the important conclusion of UPE has coherence. In the end of this paper, the UPE's application in medicine was discussed.

Color structured light system of chest wall motion measurement for respiratory volume evaluation

NASA Astrophysics Data System (ADS)

Chen, Huijun; Cheng, Yuan; Liu, Dongdong; Zhang, Xiaodong; Zhang, Jue; Que, Chengli; Wang, Guangfa; Fang, Jing

2010-03-01

We present a structured light system to dynamically measure human chest wall motion for respiratory volume estimation. Based on a projection of an encoded color pattern and a few active markers attached to the trunk, respiratory volumes are obtained by evaluating the 3-D topographic changes of the chest wall in an anatomically consistent measuring region during respiration. Three measuring setups are established: a single-sided illuminating-recording setup for standing posture, an inclined single-sided setup for supine posture, and a double-sided setup for standing posture. Results are compared with the pneumotachography and show good agreement in volume estimations [correlation coefficient: R>0.99 (P<0.001) for all setups]. The isovolume tests present small variations of the obtained volume during the isovolume maneuver (standard deviation<0.085 L for all setups). After validation by the isovolume test, an investigation of a patient with pleural effusion using the proposed method shows pulmonary functional differences between the diseased and the contralateral sides of the thorax, and subsequent improvement of this imbalance after drainage. These results demonstrate the proposed optical method is capable of not only whole respiratory volume evaluation with high accuracy, but also regional pulmonary function assessment in different chest wall behaviors, with the advantage of whole-field measurement.

Autonomous Visual Tracking of Stationary Targets Using Small Unmanned Aerial Vehicles

DTIC Science & Technology

2004-06-01

59 Figure 43. Commanded and Actual Yaw Rates during Simulation ..................................60 Figure 44. Setup for Hardware In Loop Simulation...System with AVDS Figure 44. Setup for Hardware In Loop Simulation with AVDS and PerceptiVU 2. Test Conditions Simulations were conducted for the

A versatile and reconfigurable setup for all-terahertz time-resolved pump-probe spectroscopy.

PubMed

Elezzabi, A Y; Maraghechi, P

2012-05-01

A versatile optical setup for all-terahertz (THz) time resolved pump-probe spectroscopy was designed and tested. By utilizing a dual THz pulse generator emitter module, independent and synchronized THz radiation pump and probe pulses were produced, thus eliminating the need for THz beam splitters and the limitations associated with their implementation. The current THz setup allows for precise control of the electric fields splitting ratio between the THz radiation pump and probe pulses, as well as in-phase, out-of-phase, and polarization dependent pump-probe spectroscopy. Since the present THz pump-probe setup does not require specialized THz radiation optical components, such as phase shifters, polarization rotators, or wide bandwidth beam splitters, it can be easily implemented with minimal alterations to a conventional THz time domain spectroscopy system. The present setup is valuable for studying the time dynamics of THz coherent phenomena in solid-state, chemical, and biological systems.

Improved perceptual-motor performance measurement system

NASA Technical Reports Server (NTRS)

Parker, J. F., Jr.; Reilly, R. E.

1969-01-01

Battery of tests determines the primary dimensions of perceptual-motor performance. Eighteen basic measures range from simple tests to sophisticated electronic devices. Improved system has one unit for the subject containing test display and response elements, and one for the experimenter where test setups, programming, and scoring are accomplished.

Direct Coexistence Methods to Determine the Solubility of Salts in Water from Numerical Simulations. Test Case NaCl.

PubMed

Manzanilla-Granados, Héctor M; Saint-Martín, Humberto; Fuentes-Azcatl, Raúl; Alejandre, José

2015-07-02

The solubility of NaCl, an equilibrium between a saturated solution of ions and a solid with a crystalline structure, was obtained from molecular dynamics simulations using the SPC/E and TIP4P-Ew water models. Four initial setups on supersaturated systems were tested on sodium chloride (NaCl) solutions to determine the equilibrium conditions and computational performance: (1) an ionic solution confined between two crystal plates of periodic NaCl, (2) a solution with all the ions initially distributed randomly, (3) a nanocrystal immersed in pure water, and (4) a nanocrystal immersed in an ionic solution. In some cases, the equilibration of the system can take several microseconds. The results from this work showed that the solubility of NaCl was the same, within simulation error, for the four setups, and in agreement with previously reported values from simulations with the setup (1). The system of a nanocrystal immersed in supersaturated solution was found to equilibrate faster than others. In agreement with laser-Doppler droplet measurements, at equilibrium with the solution the crystals in all the setups had a slight positive charge.

Modeling and Model Identification of Autonomous Underwater Vehicles

DTIC Science & Technology

2015-06-01

setup, based on a quadrifilar pendulum , is developed to measure the moments of inertia of the vehicle. System identification techniques, based on...parametric models of the platforms: an individual channel excitation approach and a free decay pendulum test. The former is applied to THAUS, which can...excite the system in individual channels in four degrees of freedom. These results are verified in the free decay pendulum setup, which has the

Development and testing of a homogenous multi-wavelength LED light source

NASA Astrophysics Data System (ADS)

Bolton, Frank J.; Bernat, Amir; Jacques, Steven L.; Levitz, David

2017-03-01

Multispectral imaging of human tissue is a powerful method that allows for quantify scattering and absorption parameters of the tissue and differentiate tissue types or identify pathology. This method requires imaging at multiple wavelengths and then fitting the measured data to a model based on light transport theory. Earlier, a mobile phone based multi-spectral imaging system was developed to image the uterine cervix from the colposcopy geometry, outside the patient's body at a distance of 200-300 mm. Such imaging of a distance object has inherent challenges, as bright and homogenous illumination is required. Several solutions addressing this problem were developed, with varied degrees of success. In this paper, several multi-spectral illumination setups were developed and tested for brightness and uniformity. All setups were specifically designed with low cost in mind, utilizing a printed circuit board with surface-mounted LEDs. The three setups include: LEDs illuminating the target directly, LEDs illuminating focused by a 3D printed miniature lens array, and LEDs coupled to a mixing lens and focusing optical system. In order to compare the illumination uniformity and intensity performance two experiments were performed. Test results are presented, and various tradeoffs between the three system configurations are discussed. Test results are presented, and various tradeoffs between the three system configurations are discussed.

Pupil light reflex evoked by light-emitting diode and computer screen: Methodology and association with need for recovery in daily life.

PubMed

Wang, Yang; Zekveld, Adriana A; Wendt, Dorothea; Lunner, Thomas; Naylor, Graham; Kramer, Sophia E

2018-01-01

Pupil light reflex (PLR) has been widely used as a method for evaluating parasympathetic activity. The first aim of the present study is to develop a PLR measurement using a computer screen set-up and compare its results with the PLR generated by a more conventional setup using light-emitting diode (LED). The parasympathetic nervous system, which is known to control the 'rest and digest' response of the human body, is considered to be associated with daily life fatigue. However, only few studies have attempted to test the relationship between self-reported daily fatigue and physiological measurement of the parasympathetic nervous system. Therefore, the second aim of this study was to investigate the relationship between daily-life fatigue, assessed using the Need for Recovery scale, and parasympathetic activity, as indicated by the PLR parameters. A pilot study was conducted first to develop a PLR measurement set-up using a computer screen. PLRs evoked by light stimuli with different characteristics were recorded to confirm the influence of light intensity, flash duration, and color on the PLRs evoked by the system. In the subsequent experimental study, we recorded the PLR of 25 adult participants to light flashes generated by the screen set-up as well as by a conventional LED set-up. PLR parameters relating to parasympathetic and sympathetic activity were calculated from the pupil responses. We tested the split-half reliability across two consecutive blocks of trials, and the relationships between the parameters of PLRs evoked by the two set-ups. Participants rated their need for recovery prior to the PLR recordings. PLR parameters acquired in the screen and LED set-ups showed good reliability for amplitude related parameters. The PLRs evoked by both set-ups were consistent, but showed systematic differences in absolute values of all parameters. Additionally, higher need for recovery was associated with faster and larger constriction of the PLR. This study assessed the PLR generated by a computer screen and the PLR generated by a LED. The good reliability within set-ups and the consistency between the PLRs evoked by the set-ups indicate that both systems provides a valid way to evoke the PLR. A higher need for recovery was associated with faster and larger constricting PLRs, suggesting increased levels of parasympathetic nervous system activity in people experiencing higher levels of need for recovery on a daily basis.

Testing of a flat conductor cable baseboard system for residential and commercial wiring

NASA Technical Reports Server (NTRS)

Hankins, J. D.

1974-01-01

The results of extensive testing (mechanical, electrical, chemical, environmental, thermal, and analytical) are reported for a flat conductor cable baseboard system for residential and commercial wiring. In all of the tests, Underwriters Laboratories (UL) Standards, UL Tentative Test Programs, or Accepted Engineering Practices were followed during test selection, test setup, and test accomplishment.

Development of U-frame bending system for studying the vibration integrity of spent nuclear fuel

NASA Astrophysics Data System (ADS)

Wang, Hong; Wang, Jy-An John; Tan, Ting; Jiang, Hao; Cox, Thomas S.; Howard, Rob L.; Bevard, Bruce B.; Flanagan, Michelle

2013-09-01

A bending fatigue system developed to evaluate the response of spent nuclear fuel rods to vibration loads is presented. A U-frame testing setup is used for imposing bending loads on the fuel rod specimen. The U-frame setup consists of two rigid arms, side connecting plates to the rigid arms, and linkages to a universal testing machine. The test specimen's curvature is obtained through a three-point deflection measurement method. The tests using surrogate specimens with stainless steel cladding revealed increased flexural rigidity under unidirectional cyclic bending, significant effect of cladding-pellets bonding on the response of surrogate rods, and substantial cyclic softening in reverse bending mode. These phenomena may cast light on the expected response of a spent nuclear fuel rod. The developed U-frame system is thus verified and demonstrated to be ready for further pursuit in hot-cell tests.

Setup for testing cameras for image guided surgery using a controlled NIR fluorescence mimicking light source and tissue phantom

NASA Astrophysics Data System (ADS)

Georgiou, Giota; Verdaasdonk, Rudolf M.; van der Veen, Albert; Klaessens, John H.

2017-02-01

In the development of new near-infrared (NIR) fluorescence dyes for image guided surgery, there is a need for new NIR sensitive camera systems that can easily be adjusted to specific wavelength ranges in contrast the present clinical systems that are only optimized for ICG. To test alternative camera systems, a setup was developed to mimic the fluorescence light in a tissue phantom to measure the sensitivity and resolution. Selected narrow band NIR LED's were used to illuminate a 6mm diameter circular diffuse plate to create uniform intensity controllable light spot (μW-mW) as target/source for NIR camera's. Layers of (artificial) tissue with controlled thickness could be placed on the spot to mimic a fluorescent `cancer' embedded in tissue. This setup was used to compare a range of NIR sensitive consumer's cameras for potential use in image guided surgery. The image of the spot obtained with the cameras was captured and analyzed using ImageJ software. Enhanced CCD night vision cameras were the most sensitive capable of showing intensities < 1 μW through 5 mm of tissue. However, there was no control over the automatic gain and hence noise level. NIR sensitive DSLR cameras proved relative less sensitive but could be fully manually controlled as to gain (ISO 25600) and exposure time and are therefore preferred for a clinical setting in combination with Wi-Fi remote control. The NIR fluorescence testing setup proved to be useful for camera testing and can be used for development and quality control of new NIR fluorescence guided surgery equipment.

Development of a fatigue testing setup for dielectric elastomer membrane actuators

NASA Astrophysics Data System (ADS)

Hill, M.; Rizzello, G.; Seelecke, S.

2017-04-01

Dielectric elastomers (DE's) represent a transduction technology with high potential in many fields, including industries, due to their low weight, flexibility, and small energy consumption. For industrial applications, it is of fundamental importance to quantify the lifetime of DE technology, in terms of electrical and mechanical fatigue, when operating in realistic environmental conditions. This work contributes toward this direction, by presenting the development of an experimental setup which permits systematic fatigue testing of DE membranes. The setup permits to apply both mechanical and electrical stimuli to several membranes simultaneously, while measuring at the same time their mechanical (force, deformation) and electrical response (capacitance, resistance). In its final state, the setup will allow to test up to 15 DE membranes at the same time for several thousands of cycles. Control of the modules, monitoring of the actuators, and data acquisition are realized on a cRio FPGA-system running with LabVIEW. The setup is located in a climate chamber, in order to investigate the fatigue mechanisms at different environmental conditions, i.e., in terms of temperature and humidity. The setup consists of two main parts, namely a fatigue group and a measurement group. The fatigue group stays permanently in the climate chamber, while the measurement group is assembled to the fatigue group and allows to perform measurements at 20°C.

A modified and enhanced test setup for biomechanical investigations of the hindfoot, for example in tibiotalocalcaneal arthrodesis.

PubMed

Evers, Julia; Schulze, Martin; Gehweiler, Dominic; Lakemeier, Martin; Raschke, Michael J; Wähnert, Dirk; Ochman, Sabine

2016-07-29

Tibiotalocalcaneal arthrodesis (TTCA) using intramedullary nails is a salvage procedure for many diseases in the ankle and subtalar joint. Despite "newly described intramedullary nails" with specific anatomical shapes there still remain major complications regarding this procedure. The following study presents a modified biomechanical test setup for investigations of the hindfoot. Nine fresh-frozen specimens from below the human knee were anaysed using the Hindfoot Arthrodesis Nail (Synthes) instrument. Quasi-static biomechanical testing was performed for internal/external rotation, varus/valgus and dorsal/plantar flexion using a modified established setup (physiological load entrance point, sledge at lever arm to apply pure moments). Additionally, a 3D optical measurement system was added to allow determination of interbony movements. The mean torsional range of motion (ROM) calculated from the actuator data of a material testing machine was 10.12° (SD 0.6) compared to 10° (SD 2.83) as measured with the Optotrak® system (between tibia and calcaneus). The Optotrak showed 40 % more rotation in the talocrural joint. Mean varus/valgus ROM from the material testing flexion machine was seen to be 5.65° (SD 1.84) in comparison to 2.82° (SD 0.46) measured with the Optotrak. The subtalar joint showed a 70 % higher movement when compared to the talocrural joint. Mean ROM in the flexion test was 5.3° (SD 1.45) for the material testing machine and 2.1° (SD 0.39) for the Optotrak. The movement in the talocrural joint was 3 times higher compared to the subtalar joint. The modified test setup presented here for the hindfoot allows a physiological biomechanical loading. Moreover, a detailed characterisation of the bone-implant constructs is possible.

Implementation of a noise reduction circuit for spaceflight IR spectrometers

NASA Technical Reports Server (NTRS)

Ramirez, L.; Hickok, R.; Pain, B.; Staller, C.

1992-01-01

The paper discusses the implementation and analysis of a correlated triple sampling circuit using analog subtractor/integrators. The software and test setup for noise measurements are also described. The correlation circuitry is part of the signal chain for a 256-element InSb line array used in the Visible and Infrared Mapping Spectrometer. Using a focal-plane array (FPA) simulator, system noise measurements of 0.7 DN are obtained. A test setup for FPA/SPE (signal processing electronics) characterization along with noise measurements is demonstrated.

Advanced high frequency partial discharge measuring system

NASA Technical Reports Server (NTRS)

Karady, George G.

1994-01-01

This report explains the Advanced Partial Discharge Measuring System in ASU's High Voltage Laboratory and presents some of the results obtained using the setup. While in operation an insulation is subjected to wide ranging temperature and voltage stresses. Hence, it is necessary to study the effect of temperature on the behavior of partial discharges in an insulation. The setup described in this report can be used to test samples at temperatures ranging from -50 C to 200 C. The aim of conducting the tests described herein is to be able to predict the behavior of an insulation under different operating conditions in addition to being able to predict the possibility of failure.

A novel Brain Computer Interface for classification of social joint attention in autism and comparison of 3 experimental setups: A feasibility study.

PubMed

Amaral, Carlos P; Simões, Marco A; Mouga, Susana; Andrade, João; Castelo-Branco, Miguel

2017-10-01

We present a novel virtual-reality P300-based Brain Computer Interface (BCI) paradigm using social cues to direct the focus of attention. We combined interactive immersive virtual-reality (VR) technology with the properties of P300 signals in a training tool which can be used in social attention disorders such as autism spectrum disorder (ASD). We tested the novel social attention training paradigm (P300-based BCI paradigm for rehabilitation of joint-attention skills) in 13 healthy participants, in 3 EEG systems. The more suitable setup was tested online with 4 ASD subjects. Statistical accuracy was assessed based on the detection of P300, using spatial filtering and a Naïve-Bayes classifier. We compared: 1 - g.Mobilab+ (active dry-electrodes, wireless transmission); 2 - g.Nautilus (active electrodes, wireless transmission); 3 - V-Amp with actiCAP Xpress dry-electrodes. Significant statistical classification was achieved in all systems. g.Nautilus proved to be the best performing system in terms of accuracy in the detection of P300, preparation time, speed and reported comfort. Proof of concept tests in ASD participants proved that this setup is feasible for training joint attention skills in ASD. This work provides a unique combination of 'easy-to-use' BCI systems with new technologies such as VR to train joint-attention skills in autism. Our P300 BCI paradigm is feasible for future Phase I/II clinical trials to train joint-attention skills, with successful classification within few trials, online in ASD participants. The g.Nautilus system is the best performing one to use with the developed BCI setup. Copyright © 2017 Elsevier B.V. All rights reserved.

Detection performance assessment of hand-held mine detection systems in a procurement process: test set-up for MDs and MD/GPRs

NASA Astrophysics Data System (ADS)

Schoolderman, Arnold J.; Roosenboom, Jacques H. J.

2005-06-01

The Engineers Centre of Expertise of the Royal Netherlands Army (RNLA) has conducted a study on countermine in peace operations. This study, finished in 2002, concluded that the final solution to countermine will depend in the first place on better detection of buried low-metal mines, e.g. by direct detection of the explosive components in mines. Until such detection systems are available, intermediate solutions are necessary in order to assure freedom of movement in peace operations. Because countermine operations consist of a number of different activities (area preparation, detection, clearance, etc) and the suitability of the different types of available equipment depends on the scenario, the toolbox concept for countermine equipment was adopted. In 2003 a procurement process was started in order to fill this toolbox with commercial-off-the-shelf and military-off-the-shelf equipment. The paper gives a concise description of the study on countermine operations and the procurement process, and subsequently focuses on the set-up of the tests that were conducted in the framework of the procurement of hand-held mine detection systems, like metal detectors and dual-sensor mine detectors. Programs of requirements for these systems were drawn up, aiming at systems for general use and special purpose systems. Blind tests to check the compliancy to the detection performance requirements were designed and conducted in the short timeframe that was available in the procurement process. These tests are discussed in this paper, including the set-up of the test lanes, the targets used and their depths, and the role of the operator. The tests of the capability of the detectors to discriminate small targets adjacent to large targets were conducted according the guidelines of the CEN Workshop Agreement on metal detector tests. Although the results of the tests are commercially confidential, conclusions and lessons learned from the execution of these tests are presented.

Test Operations Procedure (TOP) 02-1-100 Anthropomorphic Test Device Operation and Setup

DTIC Science & Technology

2016-02-09

using the Data Acquisition for Anthropomorphic Test Devices (D4D) in vehicle vulnerability testing. The D4D is an onboard data acquisition system ( DAS ...for Anthropomorphic Test Devices (D4D)** in vehicle vulnerability testing. The D4D is an onboard data acquisition system ( DAS ) that is intended for...use with the Hybrid II/III ATD’s. The D4D was developed to augment the existing DAS system, the legacy Versatile Information Systems Integrated On

Measurement of electromagnetic tracking error in a navigated breast surgery setup

NASA Astrophysics Data System (ADS)

Harish, Vinyas; Baksh, Aidan; Ungi, Tamas; Lasso, Andras; Baum, Zachary; Gauvin, Gabrielle; Engel, Jay; Rudan, John; Fichtinger, Gabor

2016-03-01

PURPOSE: The measurement of tracking error is crucial to ensure the safety and feasibility of electromagnetically tracked, image-guided procedures. Measurement should occur in a clinical environment because electromagnetic field distortion depends on positioning relative to the field generator and metal objects. However, we could not find an accessible and open-source system for calibration, error measurement, and visualization. We developed such a system and tested it in a navigated breast surgery setup. METHODS: A pointer tool was designed for concurrent electromagnetic and optical tracking. Software modules were developed for automatic calibration of the measurement system, real-time error visualization, and analysis. The system was taken to an operating room to test for field distortion in a navigated breast surgery setup. Positional and rotational electromagnetic tracking errors were then calculated using optical tracking as a ground truth. RESULTS: Our system is quick to set up and can be rapidly deployed. The process from calibration to visualization also only takes a few minutes. Field distortion was measured in the presence of various surgical equipment. Positional and rotational error in a clean field was approximately 0.90 mm and 0.31°. The presence of a surgical table, an electrosurgical cautery, and anesthesia machine increased the error by up to a few tenths of a millimeter and tenth of a degree. CONCLUSION: In a navigated breast surgery setup, measurement and visualization of tracking error defines a safe working area in the presence of surgical equipment. Our system is available as an extension for the open-source 3D Slicer platform.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, T; Cho, M; Kang, S

Purpose: To improve the setup accuracy of thermoplastic mask, we developed a new monitoring method based on force sensing technology and evaluated its feasibility. Methods: The thermoplastic mask setup monitoring system consists of a force sensing resistor sensor unit, a signal transport device, a control PC and an in-house software. The system is designed to monitor pressure variation between the mask and patient in real time. It also provides a warning to the user when there is a possibility of movement. A preliminary study was performed to evaluate the reliability of the sensor unit and developed monitoring system with amore » head phantom. Then, a simulation study with volunteers was conducted to evaluate the feasibility of the monitoring system. Note that the sensor unit can have multiple end-sensors and every end-sensor was confirmed to be within 2% reliability in pressure reading through a screening test. Results: To evaluate the reproducibility of the proposed monitoring system in practice, we simulated a mask setup with the head phantom. FRS sensors were attached on the face of the head phantom and pressure was monitored. For 3 repeated mask setups on the phantom, the variation of the pressure was less than 3% (only 1% larger than 2% potential uncertainty confirmed in the screening test). In the volunteer study, we intended to verify that the system could detect patient movements within the mask. Thus, volunteers were asked to turn their head or lift their chin. The system was able to detect movements effectively, confirming the clinical feasibility of the monitoring system developed. Conclusion: Through the proposed setup monitoring method, it is possible to monitor patient motion inside a mask in real time, which has never been possible with most commonly used systems using non-radiographic technology such as infrared camera system and surface imaging system. This work was supported by the Radiation Technology R&D program (No. 2013M2A2A7043498) and the Mid-career Researcher Program (2014R1A2A1A10050270) through the National Research Foundation of Korea funded by the Ministry of Science, ICT&Future Planning.« less

The Effect of Diethylene Glycol Monomethyl Ether (DiEGME) on Microbial Contamination of Jet Fuel: A Minimum Concentration Study

DTIC Science & Technology

2010-03-01

added as appropriate. Fuel was filtered with a 0.45µm hydrophobic cellulose nitrate filter (Nalge Nunc, Rochester, NY) prior to use in the test setup...it may not be clear from the images above, biofilms were also present in all 0% test setups. In fuel systems, a biofilm is a microbial growth...formation that typically appears as a sheen, pellicule, or mat that forms between the fuel and water layers or on the interior sides of a tank. Biofilms

Focus stacking: Comparing commercial top-end set-ups with a semi-automatic low budget approach. A possible solution for mass digitization of type specimens

PubMed Central

Brecko, Jonathan; Mathys, Aurore; Dekoninck, Wouter; Leponce, Maurice; VandenSpiegel, Didier; Semal, Patrick

2014-01-01

Abstract In this manuscript we present a focus stacking system, composed of commercial photographic equipment. The system is inexpensive compared to high-end commercial focus stacking solutions. We tested this system and compared the results with several different software packages (CombineZP, Auto-Montage, Helicon Focus and Zerene Stacker). We tested our final stacked picture with a picture obtained from two high-end focus stacking solutions: a Leica MZ16A with DFC500 and a Leica Z6APO with DFC290. Zerene Stacker and Helicon Focus both provided satisfactory results. However, Zerene Stacker gives the user more possibilities in terms of control of the software, batch processing and retouching. The outcome of the test on high-end solutions demonstrates that our approach performs better in several ways. The resolution of the tested extended focus pictures is much higher than those from the Leica systems. The flash lighting inside the Ikea closet creates an evenly illuminated picture, without struggling with filters, diffusers, etc. The largest benefit is the price of the set-up which is approximately € 3,000, which is 8 and 10 times less than the LeicaZ6APO and LeicaMZ16A set-up respectively. Overall, this enables institutions to purchase multiple solutions or to start digitising the type collection on a large scale even with a small budget. PMID:25589866

Focus stacking: Comparing commercial top-end set-ups with a semi-automatic low budget approach. A possible solution for mass digitization of type specimens.

PubMed

Brecko, Jonathan; Mathys, Aurore; Dekoninck, Wouter; Leponce, Maurice; VandenSpiegel, Didier; Semal, Patrick

2014-01-01

In this manuscript we present a focus stacking system, composed of commercial photographic equipment. The system is inexpensive compared to high-end commercial focus stacking solutions. We tested this system and compared the results with several different software packages (CombineZP, Auto-Montage, Helicon Focus and Zerene Stacker). We tested our final stacked picture with a picture obtained from two high-end focus stacking solutions: a Leica MZ16A with DFC500 and a Leica Z6APO with DFC290. Zerene Stacker and Helicon Focus both provided satisfactory results. However, Zerene Stacker gives the user more possibilities in terms of control of the software, batch processing and retouching. The outcome of the test on high-end solutions demonstrates that our approach performs better in several ways. The resolution of the tested extended focus pictures is much higher than those from the Leica systems. The flash lighting inside the Ikea closet creates an evenly illuminated picture, without struggling with filters, diffusers, etc. The largest benefit is the price of the set-up which is approximately € 3,000, which is 8 and 10 times less than the LeicaZ6APO and LeicaMZ16A set-up respectively. Overall, this enables institutions to purchase multiple solutions or to start digitising the type collection on a large scale even with a small budget.

Performing a Large-Scale Modal Test on the B2 Stand Crane at NASA's Stennis Space Center

NASA Technical Reports Server (NTRS)

Stasiunas, Eric C.; Parks, Russel A.

2018-01-01

A modal test of NASA’s Space Launch System (SLS) Core Stage is scheduled to occur prior to propulsion system verification testing at the Stennis Space Center B2 test stand. A derrick crane with a 180-ft long boom, located at the top of the stand, will be used to suspend the Core Stage in order to achieve defined boundary conditions. During this suspended modal test, it is expected that dynamic coupling will occur between the crane and the Core Stage. Therefore, a separate modal test was performed on the B2 crane itself, in order to evaluate the varying dynamic characteristics and correlate math models of the crane. Performing a modal test on such a massive structure was challenging and required creative test setup and procedures, including implementing both AC and DC accelerometers, and performing both classical hammer and operational modal analysis. This paper describes the logistics required to perform this large-scale test, as well as details of the test setup, the modal test methods used, and an overview of the results.

U.S. Naval Research Laboratory Final Analysis Report to NATO Above Water Warfare Capabilities Group 2016 Naval Electromagnetic Operations Trials

DTIC Science & Technology

2017-05-23

Systems and the NRL Code 5763 Radio Frequency (RF) Stimulator. It includes and covers system descriptions , setup, data collection, and test goals that...6 4. Test Asset Descriptions ...7 4.1. Description of FOXTROT Anti-ship Missile (ASM) Simulator ......................................... 7

A Preliminary Assessment of Phase Separator Ground-Based and Reduced-Gravity Testing for ALS Systems

NASA Technical Reports Server (NTRS)

Hall, Nancy Rabel

2006-01-01

A viewgraph presentation of phase separator ground-based and reduced-gravity testing for Advanced Life Support (ALS) systems is shown. The topics include: 1) Multiphase Flow Technology Program; 2) Types of Separators; 3) MOBI Phase Separators; 4) Experiment set-up; and 5) Preliminary comparison/results.

Hacking the Bell test using classical light in energy-time entanglement-based quantum key distribution.

PubMed

Jogenfors, Jonathan; Elhassan, Ashraf Mohamed; Ahrens, Johan; Bourennane, Mohamed; Larsson, Jan-Åke

2015-12-01

Photonic systems based on energy-time entanglement have been proposed to test local realism using the Bell inequality. A violation of this inequality normally also certifies security of device-independent quantum key distribution (QKD) so that an attacker cannot eavesdrop or control the system. We show how this security test can be circumvented in energy-time entangled systems when using standard avalanche photodetectors, allowing an attacker to compromise the system without leaving a trace. We reach Bell values up to 3.63 at 97.6% faked detector efficiency using tailored pulses of classical light, which exceeds even the quantum prediction. This is the first demonstration of a violation-faking source that gives both tunable violation and high faked detector efficiency. The implications are severe: the standard Clauser-Horne-Shimony-Holt inequality cannot be used to show device-independent security for energy-time entanglement setups based on Franson's configuration. However, device-independent security can be reestablished, and we conclude by listing a number of improved tests and experimental setups that would protect against all current and future attacks of this type.

Rare Earth Adsorption and Desorption with PEGDA Beads

DOE Data Explorer

Jiao, Yongqin; Brewer, Aaron; Park, Dan

2017-03-01

We synthesized PEGDA polymer hydrogel beads for cell embedding and compared REE biosorption with these beads via a gravity-driven flow through setup. One way to set up a flow through system is by cell encapsulation into polymer beads with a column setup similar to that used in the chromatography industry. To achieve this, we tested PEGDA for cell encapsulation, and tested REE biosorption under both batch mode and a follow through setup based on gravity . For making the cell embedded polymer beads, we used a fluidic device by which homogenous spherical particles of 0.5 to1 mm in diameter were synthesized. The beads are made relatively quickly, and the size of the beads can be controlled. PEGDA beads were polymerized by UV. Tb adsorption experiment was performed with beads with or without cells embedded.

Test and Evaluation of an Image-Matching Navigation System for a UAS Operating in a GPS-Denied Environment

DTIC Science & Technology

2017-09-01

NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA THESIS TEST AND EVALUATION OF AN IMAGE-MATCHING NAVIGATION SYSTEM FOR A UAS OPERATING IN A GPS-DENIED...INTENTIONALLY LEFT BLANK ii Approved for public release. Distribution is unlimited. TEST AND EVALUATION OF AN IMAGE-MATCHING NAVIGATION SYSTEM FOR A UAS... Evaluation Setup and Procedures 39 4.1 Test Equipment and Data Collection Procedures . . . . . . . . . . . . 39 4.2 Actual Flight Data Collection

Measurement of external forces and torques on a large pointing system

NASA Technical Reports Server (NTRS)

Morenus, R. C.

1980-01-01

Methods of measuring external forces and torques are discussed, in general and as applied to the Large Pointing System wind tunnel tests. The LPS tests were in two phases. The first test was a preliminary test of three models representing coelostat, heliostat, and on-gimbal telescope configurations. The second test explored the coelostat configuration in more detail. The second test used a different setup for measuring external loads. Some results are given from both tests.

Modification of a compressor performance test bench for liquid slugging observation in refrigeration compressors

NASA Astrophysics Data System (ADS)

Ola, Max; Thomas, Christiane; Hesse, Ullrich

2017-08-01

Compressor performance test procedures are defined by the standard DIN EN 13771, wherein a variety of possible calorimeter and flow rate measurement methods are suggested. One option is the selection of two independent measurement methods. The accuracies of both selected measurement methods are essential. The second option requires only one method. However the measurement accuracy of the used device has to be verified and recalibrated on a regular basis. The compressor performance test facility at the Technische Universitaet Dresden uses a calibrated flow measurement sensor, a hot gas bypass and a mixed flow heat exchanger. The test bench can easily be modified for tests of various compressor types at different operating ranges and with various refrigerants. In addition, the modified test setup enables the investigation of long term liquid slug and its effects on the compressor. The modification comprises observational components, adjustments of the control system, safety measures and a customized oil recirculation system for compressors which do not contain an integrated oil sump or oil level regulation system. This paper describes the setup of the test bench, its functional principle, the key modifications, first test results and an evaluation of the energy balance.

Remote Advanced Payload Test Rig (RAPTR) Portable Payload Test System for the International Space Station (ISS)

NASA Technical Reports Server (NTRS)

Calvert, John; Freas, George, II

2017-01-01

The RAPTR was developed to test ISS payloads for NASA. RAPTR is a simulation of the Command and Data Handling (C&DH) interfaces of the ISS (MIL-STD 1553B, Ethernet and TAXI) and is designed to facilitate rapid testing and deployment of payload experiments to the ISS. The ISS Program's goal is to reduce the amount of time it takes a payload developer to build, test and fly a payload, including payload software. The RAPTR meets this need with its user oriented, visually rich interface. Additionally, the Analog and Discrete (A&D) signals of the following payload types may be tested with RAPTR: (1) EXPRESS Sub Rack Payloads; (2) ELC payloads; (3) External Columbus payloads; (4) External Japanese Experiment Module (JEM) payloads. The automated payload configuration setup and payload data inspection infrastructure is found nowhere else in ISS payload test systems. Testing can be done with minimal human intervention and setup, as the RAPTR automatically monitors parameters in the data headers that are sent to, and come from the experiment under test.

Test Operations Procedure (TOP) 03-2-827 Test Procedures for Video Target Scoring Using Calibration Lights

DTIC Science & Technology

2016-04-04

Final 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE Test Operations Procedure (TOP) 03-2-827 Test Procedures for Video Target Scoring Using...ABSTRACT This Test Operations Procedure (TOP) describes typical equipment and procedures to setup and operate a Video Target Scoring System (VTSS) to...lights. 15. SUBJECT TERMS Video Target Scoring System, VTSS, witness screens, camera, target screen, light pole 16. SECURITY

Distribution Management System Volt/VAR Evaluation | Grid Modernization |

Science.gov Websites

NREL Distribution Management System Volt/VAR Evaluation Distribution Management System Volt/VAR Evaluation This project involves building a prototype distribution management system testbed that links a GE Grid Solutions distribution management system to power hardware-in-the-loop testing. This setup is

A Multi-Agent Environment for Negotiation

NASA Astrophysics Data System (ADS)

Hindriks, Koen V.; Jonker, Catholijn M.; Tykhonov, Dmytro

In this chapter we introduce the System for Analysis of Multi-Issue Negotiation (SAMIN). SAMIN offers a negotiation environment that supports and facilitates the setup of various negotiation setups. The environment has been designed to analyse negotiation processes between human negotiators, between human and software agents, and between software agents. It offers a range of different agents, different domains, and other options useful to define a negotiation setup. The environment has been used to test and evaluate a range of negotiation strategies in various domains playing against other negotiating agents as well as humans. We discuss some of the results obtained by means of these experiments.

Density Measurement System for Weights of 1 kg to 20 kg Using Hydrostatic Weighing

NASA Astrophysics Data System (ADS)

Lee, Yong Jae; Lee, Woo Gab; Abdurahman, Mohammed; Kim, Kwang Pyo

This paper presents a density measurement system to determine density of weights from 1 kg to 20 kg using hydrostatic weighing. The system works based on Archimedes principle. The density of reference liquid is determined using this setup while determining the density of the test weight. Density sphere is used as standard density ball to determine density of the reference liquid. A new immersion pan is designed for dual purpose to carry the density sphere and the cylindrical test weight for weighing in liquid. Main parts of the setup are an electronic balance, a thermostat controlled liquid bath, reference weights designed for bottom weighing, dual purpose immersion pans and stepping motors to load and unload in weighing process. The results of density measurement will be evaluated as uncertainties for weights of 1 kg to 20 kg.

Thermal Testing and Model Correlation for Advanced Topographic Laser Altimeter Instrument (ATLAS)

NASA Technical Reports Server (NTRS)

Patel, Deepak

2016-01-01

The Advanced Topographic Laser Altimeter System (ATLAS) part of the Ice Cloud and Land Elevation Satellite 2 (ICESat-2) is an upcoming Earth Science mission focusing on the effects of climate change. The flight instrument passed all environmental testing at GSFC (Goddard Space Flight Center) and is now ready to be shipped to the spacecraft vendor for integration and testing. This topic covers the analysis leading up to the test setup for ATLAS thermal testing as well as model correlation to flight predictions. Test setup analysis section will include areas where ATLAS could not meet flight like conditions and what were the limitations. Model correlation section will walk through changes that had to be made to the thermal model in order to match test results. The correlated model will then be integrated with spacecraft model for on-orbit predictions.

An automated pressure data acquisition system for evaluation of pressure sensitive paint chemistries

NASA Technical Reports Server (NTRS)

Sealey, Bradley S.; Mitchell, Michael; Burkett, Cecil G.; Oglesby, Donald M.

1993-01-01

An automated pressure data acquisition system for testing of pressure sensitive phosphorescent paints was designed, assembled, and tested. The purpose of the calibration system is the evaluation and selection of pressure sensitive paint chemistries that could be used to obtain global aerodynamic pressure distribution measurements. The test apparatus and setup used for pressure sensitive paint characterizations is described. The pressure calibrations, thermal sensitivity effects, and photodegradation properties are discussed.

A new reference tip-timing test bench and simulator for blade synchronous and asynchronous vibrations

NASA Astrophysics Data System (ADS)

Hajnayeb, Ali; Nikpour, Masood; Moradi, Shapour; Rossi, Gianluca

2018-02-01

The blade tip-timing (BTT) measurement technique is at present the most promising technique for monitoring the blades of axial turbines and aircraft engines in operating conditions. It is generally used as an alternative to strain gauges in turbine testing. By conducting a comparison with the standard methods such as those based on strain gauges, one determines that the technique is not intrusive and does not require a complicated installation process. Despite its superiority to other methods, the experimental performance analysis of a new BTT method needs a test stand that includes a reference measurement system (e.g. strain gauges equipped with telemetry or other complex optical measurement systems, like rotating laser Doppler vibrometers). In this article, a new reliable, low-cost BTT test setup is proposed for simulating and analyzing blade vibrations based on kinematic inversion. In the proposed test bench, instead of the blades vibrating, it is the BTT sensor that vibrates. The vibration of the sensor is generated by a shaker and can therefore be easily controlled in terms of frequency, amplitude and waveform shape. The amplitude of vibration excitation is measured by a simple accelerometer. After introducing the components of the simulator, the proposed test bench is used in practice to simulate both synchronous and asynchronous vibration scenarios. Then two BTT methods are used to evaluate the quality of the acquired data. The results demonstrate that the proposed setup is able to generate simulated pulse sequences which are almost the same as those generated by the conventional BTT systems installed around a bladed disk. Moreover, the test setup enables its users to evaluate BTT methods by using a limited number of sensors. This significantly reduces the total costs of the experiments.

Laboratory Evaluation of EGS Shear Stimulation-Test 001

DOE Data Explorer

Bauer, Steve

2014-07-29

this is the results of an initial setup-shakedon test in order to develop the plumbing system for this test design. a cylinder of granite with offset holes was jacketed and subjected to confining pressure and low temperature (85C) and pore water pressure. flow through the sample was developed at different test stages.

Broadband Fan Noise Prediction System for Turbofan Engines. Volume 3; Validation and Test Cases

NASA Technical Reports Server (NTRS)

Morin, Bruce L.

2010-01-01

Pratt & Whitney has developed a Broadband Fan Noise Prediction System (BFaNS) for turbofan engines. This system computes the noise generated by turbulence impinging on the leading edges of the fan and fan exit guide vane, and noise generated by boundary-layer turbulence passing over the fan trailing edge. BFaNS has been validated on three fan rigs that were tested during the NASA Advanced Subsonic Technology Program (AST). The predicted noise spectra agreed well with measured data. The predicted effects of fan speed, vane count, and vane sweep also agreed well with measurements. The noise prediction system consists of two computer programs: Setup_BFaNS and BFaNS. Setup_BFaNS converts user-specified geometry and flow-field information into a BFaNS input file. From this input file, BFaNS computes the inlet and aft broadband sound power spectra generated by the fan and FEGV. The output file from BFaNS contains the inlet, aft and total sound power spectra from each noise source. This report is the third volume of a three-volume set documenting the Broadband Fan Noise Prediction System: Volume 1: Setup_BFaNS User s Manual and Developer s Guide; Volume 2: BFaNS User s Manual and Developer s Guide; and Volume 3: Validation and Test Cases. The present volume begins with an overview of the Broadband Fan Noise Prediction System, followed by validation studies that were done on three fan rigs. It concludes with recommended improvements and additional studies for BFaNS.

Implementation of an anonymisation tool for clinical trials using a clinical trial processor integrated with an existing trial patient data information system.

PubMed

Aryanto, Kadek Y E; Broekema, André; Oudkerk, Matthijs; van Ooijen, Peter M A

2012-01-01

To present an adapted Clinical Trial Processor (CTP) test set-up for receiving, anonymising and saving Digital Imaging and Communications in Medicine (DICOM) data using external input from the original database of an existing clinical study information system to guide the anonymisation process. Two methods are presented for an adapted CTP test set-up. In the first method, images are pushed from the Picture Archiving and Communication System (PACS) using the DICOM protocol through a local network. In the second method, images are transferred through the internet using the HTTPS protocol. In total 25,000 images from 50 patients were moved from the PACS, anonymised and stored within roughly 2 h using the first method. In the second method, an average of 10 images per minute were transferred and processed over a residential connection. In both methods, no duplicated images were stored when previous images were retransferred. The anonymised images are stored in appropriate directories. The CTP can transfer and process DICOM images correctly in a very easy set-up providing a fast, secure and stable environment. The adapted CTP allows easy integration into an environment in which patient data are already included in an existing information system.

Energy Harvesting and Storage Systems for Future AF Vehicles

DTIC Science & Technology

2012-05-18

mechanical testing setup/procedures to determine the Young’s modulus and fracture strength of solar energy harvesting modules. Figure D1 SEM micrograph of...failure modes. (4 configurations; 2 repetitions) Table D3. Summary of mechanical testing activity The goal of the test is to determine the fracture ...

Prevention of gross setup errors in radiotherapy with an efficient automatic patient safety system.

PubMed

Yan, Guanghua; Mittauer, Kathryn; Huang, Yin; Lu, Bo; Liu, Chihray; Li, Jonathan G

2013-11-04

Treatment of the wrong body part due to incorrect setup is among the leading types of errors in radiotherapy. The purpose of this paper is to report an efficient automatic patient safety system (PSS) to prevent gross setup errors. The system consists of a pair of charge-coupled device (CCD) cameras mounted in treatment room, a single infrared reflective marker (IRRM) affixed on patient or immobilization device, and a set of in-house developed software. Patients are CT scanned with a CT BB placed over their surface close to intended treatment site. Coordinates of the CT BB relative to treatment isocenter are used as reference for tracking. The CT BB is replaced with an IRRM before treatment starts. PSS evaluates setup accuracy by comparing real-time IRRM position with reference position. To automate system workflow, PSS synchronizes with the record-and-verify (R&V) system in real time and automatically loads in reference data for patient under treatment. Special IRRMs, which can permanently stick to patient face mask or body mold throughout the course of treatment, were designed to minimize therapist's workload. Accuracy of the system was examined on an anthropomorphic phantom with a designed end-to-end test. Its performance was also evaluated on head and neck as well as abdominalpelvic patients using cone-beam CT (CBCT) as standard. The PSS system achieved a seamless clinic workflow by synchronizing with the R&V system. By permanently mounting specially designed IRRMs on patient immobilization devices, therapist intervention is eliminated or minimized. Overall results showed that the PSS system has sufficient accuracy to catch gross setup errors greater than 1 cm in real time. An efficient automatic PSS with sufficient accuracy has been developed to prevent gross setup errors in radiotherapy. The system can be applied to all treatment sites for independent positioning verification. It can be an ideal complement to complex image-guidance systems due to its advantages of continuous tracking ability, no radiation dose, and fully automated clinic workflow.

Optimization-based manufacturing scheduling with multiple resources and setup requirements

NASA Astrophysics Data System (ADS)

Chen, Dong; Luh, Peter B.; Thakur, Lakshman S.; Moreno, Jack, Jr.

1998-10-01

The increasing demand for on-time delivery and low price forces manufacturer to seek effective schedules to improve coordination of multiple resources and to reduce product internal costs associated with labor, setup and inventory. This study describes the design and implementation of a scheduling system for J. M. Product Inc. whose manufacturing is characterized by the need to simultaneously consider machines and operators while an operator may attend several operations at the same time, and the presence of machines requiring significant setup times. The scheduling problem with these characteristics are typical for many manufacturers, very difficult to be handled, and have not been adequately addressed in the literature. In this study, both machine and operators are modeled as resources with finite capacities to obtain efficient coordination between them, and an operator's time can be shared by several operations at the same time to make full use of the operator. Setups are explicitly modeled following our previous work, with additional penalties on excessive setups to reduce setup costs and avoid possible scraps. An integer formulation with a separable structure is developed to maximize on-time delivery of products, low inventory and small number of setups. Within the Lagrangian relaxation framework, the problem is decomposed into individual subproblems that are effectively solved by using dynamic programming with additional penalties embedded in state transitions. Heuristics is then developed to obtain a feasible schedule following on our previous work with new mechanism to satisfy operator capacity constraints. The method has been implemented using the object-oriented programming language C++ with a user-friendly interface, and numerical testing shows that the method generates high quality schedules in a timely fashion. Through simultaneous consideration of machines and operators, machines and operators are well coordinated to facilitate the smooth flow of parts through the system. The explicit modeling of setups and the associated penalties let parts with same setup requirements clustered together to avoid excessive setups.

Development of a Cavitation Erosion Resistant Advanced Material System

DTIC Science & Technology

2005-11-01

Sheet EPD M results .............................................................................. 47 Figure 5.11 - EPDM rubber samples, sheet (left...Testing The long test times of EPDM rubber and other durable elastomer samples created a need for overnight testing capability. In the original test setup...seals, adhesives and molded flexible parts. Common examples of elastomers include natural and synthetic rubber , silicone, neoprene, EPDM , polyurethane

X-ray phase scanning setup for non-destructive testing using Talbot-Lau interferometer

NASA Astrophysics Data System (ADS)

Bachche, S.; Nonoguchi, M.; Kato, K.; Kageyama, M.; Koike, T.; Kuribayashi, M.; Momose, A.

2016-09-01

X-ray grating interferometry has a great potential for X-ray phase imaging over conventional X-ray absorption imaging which does not provide significant contrast for weakly absorbing objects and soft biological tissues. X-ray Talbot and Talbot-Lau interferometers which are composed of transmission gratings and measure the differential X-ray phase shifts have gained popularity because they operate with polychromatic beams. In X-ray radiography, especially for nondestructive testing in industrial applications, the feasibility of continuous sample scanning is not yet completely revealed. A scanning setup is frequently advantageous when compared to a direct 2D static image acquisition in terms of field of view, exposure time, illuminating radiation, etc. This paper demonstrates an efficient scanning setup for grating-based Xray phase imaging using laboratory-based X-ray source. An apparatus consisting of an X-ray source that emits X-rays vertically, optical gratings and a photon-counting detector was used with which continuously moving objects across the field of view as that of conveyor belt system can be imaged. The imaging performance of phase scanner was tested by scanning a long continuous moving sample at a speed of 5 mm/s and absorption, differential-phase and visibility images were generated by processing non-uniform moire movie with our specially designed phase measurement algorithm. A brief discussion on the feasibility of phase scanner with scanning setup approach including X-ray phase imaging performance is reported. The successful results suggest a breakthrough for scanning objects those are moving continuously on conveyor belt system non-destructively using the scheme of X-ray phase imaging.

Experimental setup for investigation of two-phase (water-air) flows in a tube

NASA Astrophysics Data System (ADS)

Kazunin, D. V.; Lashkov, V. A.; Mashek, I. Ch.; Khoronzhuk, R. S.

2018-05-01

A special setup was designed and built at St. Petersburg State University for providing experimental research in flow dynamics of the of air-water mixtures in a pipeline. The test section of the setup allows simulating a wide range of flow regimes of a gas-liquid mixture. The parameters of the experimental setup are given; the initial test results are discussed.

Feasibility of line-ratio spectroscopy on helium and neon as edge diagnostic tool for Wendelstein 7-X

DOE PAGES

Barbui, T.; Krychowiak, M.; König, R.; ...

2016-09-27

A beam emission spectroscopy system on thermal helium (He) and neon (Ne) has been set up at Wendelstein 7-X to measure edge electron temperature and density profiles utilizing the line-ratio technique or its extension by the analysis of absolutely calibrated line emissions. The setup for a first systematic test of these techniques of quantitative atomic spectroscopy in the limiter startup phase (OP1.1) is reported together with first measured profiles. Lastly, this setup and the first results are an important test for developing the technique for the upcoming high density, low temperature island divertor regime.

Transfer orbit stage mechanisms thermal vacuum test

NASA Technical Reports Server (NTRS)

Oleary, Scott T.

1990-01-01

A systems level mechanisms test was conducted on the Orbital Sciences Corp.'s Transfer Orbit Stage (TOS). The TOS is a unique partially reusable transfer vehicle which will boost a satellite into its operational orbit from the Space Shuttle's cargo bay. The mechanical cradle and tilt assemblies will return to earth with the Space Shuttle while the Solid Rocket Motor (SRM) and avionics package are expended. A mechanisms test was performed on the forward cradle and aft tilting assemblies of the TOS under thermal vacuum conditions. Actuating these assemblies under a 1 g environment and thermal vacuum conditions proved to be a complex task. Pneumatic test fixturing was used to lift the forward cradle, and tilt the SRM, and avionics package. Clinometers, linear voltage displacement transducers, and load cells were used in the thermal vacuum chamber to measure the performance and characteristics of the TOS mechanism assembly. Incorporation of the instrumentation and pneumatic system into the test setup was not routine since pneumatic actuation of flight hardware had not been previously performed in the facility. The methods used are presented along with the problems experienced during the design, setup and test phases.

Software control program for 25 kW breadboard testing. [spacecraft power supplies; high voltage batteries

NASA Technical Reports Server (NTRS)

Pajak, J. A.

1981-01-01

A data acquisition software program developed to operate in conjunction with the automated control system of the 25 kW PM Electric Power System Breadboard Test facility is described. The proram provides limited interactive control of the breadboard test while acquiring data and monitoring parameters, allowing unattended continuous operation. The breadboard test facility has two positions for operating separate configurations. The main variable in each test setup is the high voltage Ni-Cd battery.

Automated Iodine Monitoring System Development (AIMS). [shuttle prototype

NASA Technical Reports Server (NTRS)

1975-01-01

The operating principle of the automated iodine monitoring/controller system (AIMS) is described along with several design modifications. The iodine addition system is also discussed along with test setups and calibration; a facsimile of the optical/mechanical portion of the iodine monitor was fabricated and tested. The appendices include information on shuttle prototype AIMS, preliminary prime item development specifications, preliminary failure modes and effects analysis, and preliminary operating and maintenance instructions.

A performance evaluation of various coatings, substrate materials, and solar collector systems

NASA Technical Reports Server (NTRS)

Dolan, F. J.

1976-01-01

An experimental apparatus was constructed and utilized in conjunction with both a solar simulator and actual sunlight to test and evaluate various solar panel coatings, panel designs, and scaled-down collector subsystems. Data were taken by an automatic digital data acquisition system and reduced and printed by a computer system. The solar collector test setup, data acquisition system, and data reduction and printout systems were considered to have operated very satisfactorily. Test data indicated that there is a practical or useful limit in scaling down beyond which scaled-down testing cannot produce results comparable to results of larger scale tests. Test data are presented as are schematics and pictures of test equipment and test hardware.

A versatile fiber-optic coupled system for sensitive optical spectroscopy in strong ambient light

NASA Astrophysics Data System (ADS)

Sinha, Sudarson Sekhar; Verma, Pramod Kumar; Makhal, Abhinandan; Pal, Samir Kumar

2009-05-01

In this work we describe design and use of a fiber-optic based optical system for the spectroscopic studies on the samples under the presence of strong ambient light. The system is tested to monitor absorption, emission, and picosecond-resolved fluorescence transients simultaneously with a time interval of 500 ms for several hours on a biologically important sample (vitamin B2) under strong UV light. An efficient stray-light rejection ratio of the setup is achieved by the confocal geometry of the excitation and detection channels. It is demonstrated using this setup that even low optical signal from a liquid sample under strong UV-exposure for the picosecond-resolved fluorescence transient measurement can reliably be detected by ultrasensitive microchannel plate photomultiplier tube solid state detector. The kinetics of photodeterioration of vitamin B2 measured using our setup is consistent with that reported in the literature. Our present studies also justify the usage of tungsten light than the fluorescent light for the healthy preservation of food with vitamin B2.

A portable gas recirculation unit for gaseous detectors

NASA Astrophysics Data System (ADS)

Guida, R.; Mandelli, B.

2017-10-01

The use of greenhouse gases (usually C2H2F4, CF4 and SF6) is sometimes necessary to achieve the required performance for some gaseous detectors. The consumption of these gases in the LHC systems is reduced by recycling the gas mixture thanks to a complex gas recirculation system. Beyond greenhouse gas consumption due to LHC systems, a considerable contribution is generated by setups used for LHC detector upgrade projects, R&D activities, detector quality assurance or longevity tests. In order to minimise this emission, a new flexible and portable gas recirculation unit has been developed. Thanks to its low price, flexibility and user-friendly operation it can be easily adapted for the different types of detector systems and set-ups.

A dedicated AMS setup for medium mass isotopes at the Cologne FN tandem accelerator

NASA Astrophysics Data System (ADS)

Schiffer, M.; Altenkirch, R.; Feuerstein, C.; Müller-Gatermann, C.; Hackenberg, G.; Herb, S.; Bhandari, P.; Heinze, S.; Stolz, A.; Dewald, A.

2017-09-01

AMS measurements of medium mass isotopes, e.g. of 53Mn and 60Fe, are gaining interest in various fields of operation, especially geoscience. Therefore a dedicated AMS setup has been built at the Cologne 10 MV FN tandem accelerator. This setup is designed to obtain a sufficient suppression of the stable isobars at energies around 100 MeV. In this contribution we report on the actual status of the new setup and the first in-beam tests of its individual components. The isobar suppression is done with (dE/dx) techniques using combinations of energy degrader foils with an electrostatic analyzer (ESA) and a time of flight (ToF) system, as well as a (dE/dx),E gas ionization detector. Furthermore, the upgraded ion source and its negative ion yield measurement for MnO- are presented.

Feasibility study of a take-home array-based functional electrical stimulation system with automated setup for current functional electrical stimulation users with foot-drop.

PubMed

Prenton, Sarah; Kenney, Laurence P; Stapleton, Claire; Cooper, Glen; Reeves, Mark L; Heller, Ben W; Sobuh, Mohammad; Barker, Anthony T; Healey, Jamie; Good, Timothy R; Thies, Sibylle B; Howard, David; Williamson, Tracey

2014-10-01

To investigate the feasibility of unsupervised community use of an array-based automated setup functional electrical stimulator for current foot-drop functional electrical stimulation (FES) users. Feasibility study. Gait laboratory and community use. Participants (N=7) with diagnosis of unilateral foot-drop of central neurologic origin (>6mo) who were regular users of a foot-drop FES system (>3mo). Array-based automated setup FES system for foot-drop (ShefStim). Logged usage, logged automated setup times for the array-based automated setup FES system and diary recording of problems experienced, all collected in the community environment. Walking speed, ankle angles at initial contact, foot clearance during swing, and the Quebec User Evaluation of Satisfaction with Assistive Technology version 2.0 (QUEST version 2.0) questionnaire, all collected in the gait laboratory. All participants were able to use the array-based automated setup FES system. Total setup time took longer than participants' own FES systems, and automated setup time was longer than in a previous study of a similar system. Some problems were experienced, but overall, participants were as satisfied with this system as their own FES system. The increase in walking speed (N=7) relative to no stimulation was comparable between both systems, and appropriate ankle angles at initial contact (N=7) and foot clearance during swing (n=5) were greater with the array-based automated setup FES system. This study demonstrates that an array-based automated setup FES system for foot-drop can be successfully used unsupervised. Despite setup's taking longer and some problems, users are satisfied with the system and it would appear as effective, if not better, at addressing the foot-drop impairment. Further product development of this unique system, followed by a larger-scale and longer-term study, is required before firm conclusions about its efficacy can be reached. Copyright © 2014 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Health maintenance facility: Dental equipment requirements

NASA Technical Reports Server (NTRS)

Young, John; Gosbee, John; Billica, Roger

1991-01-01

The objectives were to test the effectiveness of the Health Maintenance Facility (HMF) dental suction/particle containment system, which controls fluids and debris generated during simulated dental treatment, in microgravity; to test the effectiveness of fiber optic intraoral lighting systems in microgravity, while simulating dental treatment; and to evaluate the operation and function of off-the-shelf dental handheld instruments, namely a portable dental hand drill and temporary filling material, in microgravity. A description of test procedures, including test set-up, flight equipment, and the data acquisition system, is given.

[Testing the efficacy of disinfectants during drinking water treatment. A new experimental set-up at the German EPA (Umweltbundesamt - UBA)].

PubMed

Grützmacher, G; Bartel, H; Althoff, H W; Clemen, S

2007-03-01

A set-up for experiments in the flow-through mode was constructed in order to test the efficacy of substances used for disinfecting water during drinking water treatment. A flow-through mode - in contrast to experiments under stationary conditions (so-called batch experiments) - was chosen, because this experimental design allows experiments to be carried out under constant conditions for an extended time (up to one week) and because efficacy testing is possible repeatedly, simultaneously and under exactly the same conditions for short (about 0.5 min) and also longer (about 47 min) contact times. With this experimental design the effect of biofilms along the inner pipe surfaces can be included in the observations. The construction of the experimental set-up is based on experience with laboratory flow-through systems that were installed by the UBA's drinking water department (formerly Institute for Water-, Soil- and Air Hygiene (WaBoLu) Institute) for testing disinfection with chlorine. In the first step, a test pipe for the simulation of a water works situation was installed. Water of different qualities can be mixed in large volumes beforehand so that the experimental procedure can be run with constant water quality for a minimum of one week. The kinetics of the disinfection reaction can be observed by extracting samples from eight sampling ports situated along the test pipe. In order to assign exact residence times to each of the sampling ports, tracer experiments were performed prior to testing disinfectant efficacy. This paper gives the technical details of the experimental set-up and presents the results of the tracer experiments to provide an introduction with respect to its potential.

Effects of bergamot ( Citrus bergamia (Risso) Wright & Arn.) essential oil aromatherapy on mood states, parasympathetic nervous system activity, and salivary cortisol levels in 41 healthy females.

PubMed

Watanabe, Eri; Kuchta, Kenny; Kimura, Mari; Rauwald, Hans Wilhelm; Kamei, Tsutomu; Imanishi, Jiro

2015-01-01

Bergamot essential oil (BEO) is commonly used against psychological stress and anxiety in aromatherapy. The primary aim of the present study was to obtain first clinical evidence for these psychological and physiological effects. A secondary aim was to achieve some fundamental understanding of the relevant pharmacological processes. Endocrinological, physiological, and psychological effects of BEO vapor inhalation on 41 healthy females were tested using a random crossover study design. Volunteers were exposed to 3 experimental setups (rest (R), rest + water vapor (RW), rest + water vapor + bergamot essential oil (RWB)) for 15 min each. Immediately after each setup, saliva samples were collected and the volunteers rested for 10 min. Subsequently, they completed the Profile of Mood States, State-Trait Anxiety Inventory, and Fatigue Self-Check List. High-frequency (HF) heart rate values, an indicator for parasympathetic nervous system activity, were calculated from heart rate variability values measured both during the 15 min of the experiment and during the subsequent 10 min of rest. Salivary cortisol (CS) levels in the saliva samples were analyzed using ELISA. CS of all 3 conditions R, RW, and RWB were found to be significantly distinct (p = 0.003). In the subsequent multiple comparison test, the CS value of RWB was significantly lower when compared to the R setup. When comparing the HF values of the RWB setup during the 10 min of rest after the experiment to those of RW, this parameter was significantly increased (p = 0.026) in the RWB setup for which scores for negative emotions and fatigue were also improved. These results demonstrate that BEO inhaled together with water vapor exerts psychological and physiological effects in a relatively short time. © 2015 S. Karger GmbH, Freiburg.

Characterization and calibration of gas sensor systems at ppb level—a versatile test gas generation system

NASA Astrophysics Data System (ADS)

Leidinger, Martin; Schultealbert, Caroline; Neu, Julian; Schütze, Andreas; Sauerwald, Tilman

2018-01-01

This article presents a test gas generation system designed to generate ppb level gas concentrations from gas cylinders. The focus is on permanent gases and volatile organic compounds (VOCs) for applications like indoor and outdoor air quality monitoring or breath analysis. In the design and the setup of the system, several issues regarding handling of trace gas concentrations have been considered, addressed and tested. This concerns not only the active fluidic components (flow controllers, valves), which have been chosen specifically for the task, but also the design of the fluidic tubing regarding dead volumes and delay times, which have been simulated for the chosen setup. Different tubing materials have been tested for their adsorption/desorption characteristics regarding naphthalene, a highly relevant gas for indoor air quality monitoring, which has generated high gas exchange times in a previous gas mixing system due to long time adsorption/desorption effects. Residual gas contaminations of the system and the selected carrier air supply have been detected and quantified using both an analytical method (GC-MS analysis according to ISO 16000-6) and a metal oxide semiconductor gas sensor, which detected a maximum contamination equivalent to 28 ppb of carbon monoxide. A measurement strategy for suppressing even this contamination has been devised, which allows the system to be used for gas sensor and gas sensor system characterization and calibration in the low ppb concentration range.

Investigation of periodically driven systems by x-ray absorption spectroscopy using asynchronous data collection mode

NASA Astrophysics Data System (ADS)

Singh, H.; Donetsky, D.; Liu, J.; Attenkofer, K.; Cheng, B.; Trelewicz, J. R.; Lubomirsky, I.; Stavitski, E.; Frenkel, A. I.

2018-04-01

We report the development, testing, and demonstration of a setup for modulation excitation spectroscopy experiments at the Inner Shell Spectroscopy beamline of National Synchrotron Light Source - II. A computer algorithm and dedicated software were developed for asynchronous data processing and analysis. We demonstrate the reconstruction of X-ray absorption spectra for different time points within the modulation pulse using a model system. This setup and the software are intended for a broad range of functional materials which exhibit structural and/or electronic responses to the external stimulation, such as catalysts, energy and battery materials, and electromechanical devices.

A central microprocessor controlled electrical storage heating system

NASA Astrophysics Data System (ADS)

Horstmann, H.

1980-12-01

The use of a microprocessor to control the reloading of electrical storage heaters not only during the night, but whenever the electrical grid is cycled down, was tested. The test setup, used to control a total of about 10 MW installed storage heating in 96 dwellings, is described. It is demonstrated that additional consumers can be connected to the system without demand for more power stations.

SU-F-J-21: Clinical Evaluation of Surface Scanning Systems in Different Treatment Locations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moser, T; Karger, C; Stefanowicz, S

Purpose: To reduce imaging dose in fractionated IGRT, the ability of optical surface imaging systems (OSIS) to detect setup errors was tested. Therefore, clinical studies to evaluate for different treatment locations setup corrections derived by OSIS in comparison with x-ray image guidance in fractionated radiation therapy was performed. Methods: The setup correction accuracy of an OSIS system (AlignRT, VisionRT, London, UK) will be analysed for the 4 tumour locations Pelvis, Upper Abdomen, Thorax and Breast, 20 patients for each location in comparison to a different system (Sentinel, C-RAD, SE). For each patient, the setup corrections of the cone-beam computed tomographymore » (CBCT) of an Elekta Versa HD linear accelerator (Elekta, Crawley, UK) is considered as gold-standard and then compared with those of the OSIS for the first ten fractions retrospectively. There were no clinical decisions made based on the surrogate system. For the OSIS, the reference surface is highly important as it represents the actual ground truth. It can be obtained either with the system itself or the surface structure delineated in the planning CT can be imported via DICOM interface. In this paper, the first results for the treatment region thorax are presented. The reference image modalities were compared. Results: Table 1 displays the difference between the setup corrections obtained with OSIS and CBCT in lateral (LAT), longitudinal (LNG) and vertical (VRT) direction for the DICOM reference image. While the median deviations are within a few millimeters, some outliers showed large deviations. Generally, the mean deviation as well as the spread was smallest in lateral and largest in vertical direction. Conclusion: Although the system allows fast, simple and non-invasive determination of setup corrections, it should be evaluated treatment region dependant. Therefore, the study is ongoing. The application of OSIS may help to reduce the imaging dose for the patient. We gratefully acknowledge the support by our colleagues from the Radiological University Clinic Heidelberg, where the study was performed. This work was funded by the Federal Ministry of Education and Research (BMBF) Germany, grant number 01IB13001B.« less

Large format array controller (aLFA-C): tests and characterisation at ESA

NASA Astrophysics Data System (ADS)

Lemmel, Frédéric; ter Haar, Jörg; van der Biezen, John; Duvet, Ludovic; Nelms, Nick; Blommaert, Sander; Butler, Bart; van der Luijt, Cornelis; Heijnen, Jerko; Smit, Hans; Visser, Ivo

2016-08-01

For future near infrared astronomy missions, ESA is developing a complete detection and conversion chain (photon to SpaceWire chain system): Large Format Array (aLFA-N) based on MCT type detectors. aLFA-C (Astronomy Large Format Array Controller): a versatile cryogenic detector controller. An aLFA-C prototype was developed by Caeleste (Belgium) under ESA contract (400106260400). To validate independently the performances of the aLFA-C prototype and consolidate the definition of the follow-on activity, a dedicated test bench has been designed and developed in ESTEC/ESA within the Payload Technology Validation group. This paper presents the test setup and the performance validation of the first prototype of this controller at room and cryogenic temperature. Test setup and software needed to test the HAWAII-2RG and aLFA-N detectors with the aLFA-C prototype at cryogenic temperature will be also presented.

Experimental setup for Single Event Effects at the São Paulo 8UD Pelletron Accelerator

NASA Astrophysics Data System (ADS)

Aguiar, V. A. P.; Added, N.; Medina, N. H.; Macchione, E. L. A.; Tabacniks, M. H.; Aguirre, F. R.; Silveira, M. A. G.; Santos, R. B. B.; Seixas, L. E.

2014-08-01

In this work we present an experimental setup mounted in one of the beam lines at the São Paulo 8UD Pelletron Accelerator in order to study Single Event Effects in electronic devices. The basic idea is to use elastic scattering collisions to achieve a low-flux with a high-uniformity ion beam to irradiate several devices. 12C, 16O, 28Si, 35Cl and 63Cu beams were used to test the experimental setup. In this system it is possible to use efficiently LET values of 17 MeV/mg/cm2 for an external beam arrangement and up to 32 MeV/mg/cm2 for in-vacuum irradiation.

SU-E-J-22: A Feasibility Study On KV-Based Whole Breast Radiation Patient Setup

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang, Q; Zhang, M; Yue, N

Purpose: In room kilovoltage x-ray (kV) imaging provides higher contrast than Megavoltage (MV) imaging with faster acquisition time compared with on-board cone-beam computed tomography (CBCT), thus improving patient setup accuracy and efficiency. In this study we evaluated the clinical feasibility of utilizing kV imaging for whole breast radiation patient setup. Methods: For six breast cancer patients with whole breast treatment plans using two opposed tangential fields, MV-based patient setup was conducted by aligning patient markers with in room lasers and MV portal images. Beam-eye viewed kV images were acquired using Varian OBI system after the set up process. In housemore » software was developed to transfer MLC blocks information overlaying onto kV images to demonstrate the field shape for verification. KV-based patient digital shift was derived by performing rigid registration between kV image and the digitally reconstructed radiography (DRR) to align the bony structure. This digital shift between kV-based and MV-based setup was defined as setup deviation. Results: Six sets of kV images were acquired for breast patients. The mean setup deviation was 2.3mm, 2.2mm and 1.8mm for anterior-posterior, superior-inferior and left-right direction respectively. The average setup deviation magnitude was 4.3±1.7mm for six patients. Patient with large breast had a larger setup deviation (4.4–6.2mm). There was no strong correlation between MV-based shift and setup deviation. Conclusion: A preliminary clinical workflow for kV-based whole breast radiation setup was established and tested. We observed setup deviation of the magnitude below than 5mm. With the benefit of providing higher contrast and MLC block overlaid on the images for treatment field verification, it is feasible to use kV imaging for breast patient setup.« less

Experimental tests of coherence and entanglement conservation under unitary evolutions

NASA Astrophysics Data System (ADS)

Černoch, Antonín; Bartkiewicz, Karol; Lemr, Karel; Soubusta, Jan

2018-04-01

We experimentally demonstrate the migration of coherence between composite quantum systems and their subsystems. The quantum systems are implemented using polarization states of photons in two experimental setups. The first setup is based on a linear optical controlled-phase quantum gate and the second scheme utilizes effects of nonlinear optics. Our experiment allows one to verify the relation between correlations of the subsystems and the coherence of the composite system, which was given in terms of a conservation law for maximal accessible coherence by Svozilík et al. [J. Svozilík et al., Phys. Rev. Lett. 115, 220501 (2015), 10.1103/PhysRevLett.115.220501]. We observe that the maximal accessible coherence is conserved for the implemented class of global evolutions of the composite system.

Flight Tests of a 0.13-Scale Model of the Convair XFY-1 Vertically Rising Airplane in a Setup Simulating that Proposed for Captive-Flight Tests in a Hangar, TED No. NACA DE 368

NASA Technical Reports Server (NTRS)

Lovell, Powell M., Jr.

1953-01-01

An experimental investigation has been conducted to determine the dynamic stability and control characteristics of a 0.13-scale free-flight model of the Convair XFY-1 airplane in test setups representing the setup proposed for use in the first flight tests of the full-scale airplane in the Moffett Field airship hangar. The investigation was conducted in two parts: first, tests with the model flying freely in an enclosure simulating the hangar, and second, tests with the model partially restrained by an overhead line attached to the propeller spinner and ground lines attached to the wing and tail tips. The results of the tests indicated that the airplane can be flown without difficulty in the Moffett Field airship hangar if it does not approach too close to the hangar walls. If it does approach too close to the walls, the recirculation of the propeller slipstream might cause sudden trim changes which would make smooth flight difficult for the pilot to accomplish. It appeared that the tethering system proposed by Convair could provide generally satisfactory restraint of large-amplitude motions caused by control failure or pilot error without interfering with normal flying or causing any serious instability or violent jerking motions as the tethering lines restrained the model.

TH-EF-BRB-11: Volumetric Modulated Arc Therapy for Total Body Irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ouyang, L; Folkerts, M; Hrycushko, B

Purpose: To develop a modern, patient-comfortable total body irradiation (TBI) technique suitable for standard-sized linac vaults. Methods: An indexed rotatable immobilization system (IRIS) was developed to make possible total-body CT imaging and radiation delivery on conventional couches. Treatment consists of multi-isocentric volumetric modulated arc therapy (VMAT) to the upper body and parallel-opposed fields to the lower body. Each isocenter is indexed to the couch and includes a 180° IRIS rotation between the upper and lower body fields. VMAT fields are optimized to satisfy lung dose objectives while achieving a uniform therapeutic dose to the torso. End-to-end tests with a randomore » phantom were used to verify dosimetric characteristics. Treatment plan robustness regarding setup uncertainty was assessed by simulating global and regional isocenter setup shifts on patient data sets. Dosimetric comparisons were made with conventional extended distance, standing TBI (cTBI) plans using a Monte Carlo-based calculation. Treatment efficiency was assessed for eight courses of patient treatment. Results: The IRIS system is level and orthogonal to the scanned CT image plane, with lateral shifts <2mm following rotation. End-to-end tests showed surface doses within ±10% of the prescription dose, field junction doses within ±15% of prescription dose. Plan robustness tests showed <15% changes in dose with global setup errors up to 5mm in each direction. Local 5mm relative setup errors in the chest resulted in < 5% dose changes. Local 5mm shift errors in the pelvic and upper leg junction resulted in <10% dose changes while a 10mm shift error causes dose changes up to 25%. Dosimetric comparison with cTBI showed VMAT-TBI has advantages in preserving chest wall dose with flexibility in leveraging the PTV-body and PTV-lung dose. Conclusion: VMAT-TBI with the IRIS system was shown clinically feasible as a cost-effective approach to TBI for standard-sized linac vaults.« less

Comparative evaluation of user interfaces for robot-assisted laser phonomicrosurgery.

PubMed

Dagnino, Giulio; Mattos, Leonardo S; Becattini, Gabriele; Dellepiane, Massimo; Caldwell, Darwin G

2011-01-01

This research investigates the impact of three different control devices and two visualization methods on the precision, safety and ergonomics of a new medical robotic system prototype for assistive laser phonomicrosurgery. This system allows the user to remotely control the surgical laser beam using either a flight simulator type joystick, a joypad, or a pen display system in order to improve the traditional surgical setup composed by a mechanical micromanipulator coupled with a surgical microscope. The experimental setup and protocol followed to obtain quantitative performance data from the control devices tested are fully described here. This includes sets of path following evaluation experiments conducted with ten subjects with different skills, for a total of 700 trials. The data analysis method and experimental results are also presented, demonstrating an average 45% error reduction when using the joypad and up to 60% error reduction when using the pen display system versus the standard phonomicrosurgery setup. These results demonstrate the new system can provide important improvements in terms of surgical precision, ergonomics and safety. In addition, the evaluation method presented here is shown to support an objective selection of control devices for this application.

An electromechanical, patient positioning system for head and neck radiotherapy

NASA Astrophysics Data System (ADS)

Ostyn, Mark; Dwyer, Thomas; Miller, Matthew; King, Paden; Sacks, Rachel; Cruikshank, Ross; Rosario, Melvin; Martinez, Daniel; Kim, Siyong; Yeo, Woon-Hong

2017-09-01

In cancer treatment with radiation, accurate patient setup is critical for proper dose delivery. Improper arrangement can lead to disease recurrence, permanent organ damage, or lack of disease control. While current immobilization equipment often helps for patient positioning, manual adjustment is required, involving iterative, time-consuming steps. Here, we present an electromechanical robotic system for improving patient setup in radiotherapy, specifically targeting head and neck cancer. This positioning system offers six degrees of freedom for a variety of applications in radiation oncology. An analytical calculation of inverse kinematics serves as fundamental criteria to design the system. Computational mechanical modeling and experimental study of radiotherapy compatibility and x-ray-based imaging demonstrates the device feasibility and reliability to be used in radiotherapy. An absolute positioning accuracy test in a clinical treatment room supports the clinical feasibility of the system.

Performance of the Primary Mirror Center-of-Curvature Optical Metrology System during Cryogenic Testing of the JWST Pathfinder Telescope

NASA Technical Reports Server (NTRS)

Hadaway, James B.; Wells, Conrad; Olczak, Gene; Waldman, Mark; Whitman, Tony; Cosentino, Joseph; Connolly, Mark; Chaney, David; Telfer, Randal

2016-01-01

The JWST primary mirror consists of 18 1.5 m hexagonal segments, each with 6-DoF and RoC adjustment. The telescope will be tested at its cryogenic operating temperature at Johnson Space Center. The testing will include center-of-curvature measurements of the PM, using the Center-of-Curvature Optical Assembly (COCOA) and the Absolute Distance Meter Assembly (ADMA). The performance of these metrology systems, including hardware, software, procedures, was assessed during two cryogenic tests at JSC, using the JWST Pathfinder telescope. This paper describes the test setup, the testing performed, and the resulting metrology system performance.

Establishment of a VISAR Measurement System for Material Model Validation in DSTO

DTIC Science & Technology

2013-02-01

advancements published in the works by L.M. Baker, E.R. Hollenbach and W.F. Hemsing [1-3] and results in the user-friendly interface and configuration of the...VISAR system [4] used in the current work . VISAR tests are among the mandatory instrumentation techniques when validating material models and...The present work reports on preliminary tests using the recently commissioned DSTO VISAR system, providing an assessment of the experimental set-up

Broadband Fan Noise Prediction System for Turbofan Engines. Volume 2; BFaNS User's Manual and Developer's Guide

NASA Technical Reports Server (NTRS)

Morin, Bruce L.

2010-01-01

Pratt & Whitney has developed a Broadband Fan Noise Prediction System (BFaNS) for turbofan engines. This system computes the noise generated by turbulence impinging on the leading edges of the fan and fan exit guide vane, and noise generated by boundary-layer turbulence passing over the fan trailing edge. BFaNS has been validated on three fan rigs that were tested during the NASA Advanced Subsonic Technology Program (AST). The predicted noise spectra agreed well with measured data. The predicted effects of fan speed, vane count, and vane sweep also agreed well with measurements. The noise prediction system consists of two computer programs: Setup_BFaNS and BFaNS. Setup_BFaNS converts user-specified geometry and flow-field information into a BFaNS input file. From this input file, BFaNS computes the inlet and aft broadband sound power spectra generated by the fan and FEGV. The output file from BFaNS contains the inlet, aft and total sound power spectra from each noise source. This report is the second volume of a three-volume set documenting the Broadband Fan Noise Prediction System: Volume 1: Setup_BFaNS User s Manual and Developer s Guide; Volume 2: BFaNS User s Manual and Developer s Guide; and Volume 3: Validation and Test Cases. The present volume begins with an overview of the Broadband Fan Noise Prediction System, followed by step-by-step instructions for installing and running BFaNS. It concludes with technical documentation of the BFaNS computer program.

Measurement of SO2 and SO3 using a tunable diode laser system

NASA Astrophysics Data System (ADS)

Berkoff, Timothy A.; Wormhoudt, Joda C.; Miake-Lye, R. C.

1999-02-01

We describe the set-up and operation of a mid-infrared (lead- salt) tunable diode laser system used to measure SO2 and SO3 levels in the exhaust plume of an aircraft engine in an altitude test chamber. These measurements were part of an on-going effort to determine the sulfur emission and conversion of SO2 to SO3 in a representative exhaust under different altitudes, power conditions, and fuel sulfur loadings. Results obtained using this set-up demonstrate the ability to measure SO2 concentrations in the low ppmv range and the possibility of detecting SO3 when it is present at similar levels.

Introduction to an Open Source Internet-Based Testing Program for Medical Student Examinations

PubMed Central

2009-01-01

The author developed a freely available open source internet-based testing program for medical examination. PHP and Java script were used as the programming language and postgreSQL as the database management system on an Apache web server and Linux operating system. The system approach was that a super user inputs the items, each school administrator inputs the examinees' information, and examinees access the system. The examinee's score is displayed immediately after examination with item analysis. The set-up of the system beginning with installation is described. This may help medical professors to easily adopt an internet-based testing system for medical education. PMID:20046457

Introduction to an open source internet-based testing program for medical student examinations.

PubMed

Lee, Yoon-Hwan

2009-12-20

The author developed a freely available open source internet-based testing program for medical examination. PHP and Java script were used as the programming language and postgreSQL as the database management system on an Apache web server and Linux operating system. The system approach was that a super user inputs the items, each school administrator inputs the examinees' information, and examinees access the system. The examinee's score is displayed immediately after examination with item analysis. The set-up of the system beginning with installation is described. This may help medical professors to easily adopt an internet-based testing system for medical education.

A novel single compartment in vitro model for electrophysiological research using the perfluorocarbon FC-770.

PubMed

Choudhary, M; Clavica, F; van Mastrigt, R; van Asselt, E

2016-06-20

Electrophysiological studies of whole organ systems in vitro often require measurement of nerve activity and/or stimulation of the organ via the associated nerves. Currently two-compartment setups are used for such studies. These setups are complicated and require two fluids in two separate compartments and stretching the nerve across one chamber to the other, which may damage the nerves. We aimed at developing a simple single compartment setup by testing the electrophysiological properties of FC-770 (a perfluorocarbon) for in vitro recording of bladder afferent nerve activity and electrical stimulation of the bladder. Perflurocarbons are especially suitable for such a setup because of their high oxygen carrying capacity and insulating properties. In male Wistar rats, afferent nerve activity was recorded from postganglionic branches of the pelvic nerve in vitro, in situ and in vivo. The bladder was stimulated electrically via the efferent nerves. Organ viability was monitored by recording spontaneous contractions of the bladder. Additionally, histological examinations were done to test the effect of FC-770 on the bladder tissue. Afferent nerve activity was successfully recorded in a total of 11 rats. The bladders were stimulated electrically and high amplitude contractions were evoked. Histological examinations and monitoring of spontaneous contractions showed that FC-770 maintained organ viability and did not cause damage to the tissue. We have shown that FC-770 enables a simple, one compartment in vitro alternative for the generally used two compartment setups for whole organ electrophysiological studies.

Reducing absorbed dose to eye lenses in head CT examinations: the effect of bismuth shielding.

PubMed

Ciarmatori, Alberto; Nocetti, L; Mistretta, G; Zambelli, G; Costi, T

2016-06-01

The eye lens is considered to be among the most radiosensitive human tissues. Brain CT scans may unnecessarily expose it to radiation even if the area of clinical interest is far from the eyes. The aim of this study is to implement a bismuth eye lens shielding system for Head-CT acquisitions in these cases. The study is focused on the assessment of the dosimetric characteristics of the shielding system as well as on its effect on image quality. The shielding system was tested in two set-ups which differ for distance ("contact" and "4 cm" Set up respectively). Scans were performed on a CTDI phantom and an anthropomorphic phantom. A reference set up without shielding system was acquired to establish a baseline. Image quality was assessed by signal (not HU converted), noise and contrast-to-noise ratio (CNR) evaluation. The overall dose reduction was evaluated by measuring the CTDIvol while the eye lens dose reduction was assessed by placing thermoluminescent dosimeters (TLDs) on an anthropomorphic phantom. The image quality analysis exhibits the presence of an artefact that mildly increases the CT number up to 3 cm below the shielding system. Below the artefact, the difference of the Signal and the CNR are negligible between the three different set-ups. Regarding the CTDI, the analysis demonstrates a decrease by almost 12 % (in the "contact" set-up) and 9 % (in the "4 cm" set-up). TLD measurements exhibit an eye lens dose reduction by 28.5 ± 5 and 21.1 ± 5 % respectively at the "contact" and the "4 cm" distance. No relevant artefact was found and image quality was not affected by the shielding system. Significant dose reductions were measured. These features make the shielding set-up useful for clinical implementation in both studied positions.

Combination of thermal and electric properties' measurement techniques in a single setup suitable for radioactive materials in controlled environments and based on the 3ω approach

NASA Astrophysics Data System (ADS)

Shrestha, K.; Gofryk, K.

2018-04-01

We have designed and developed a new experimental setup, based on the 3ω method, to measure thermal conductivity, heat capacity, and electrical resistivity of a variety of samples in a broad temperature range (2-550 K) and under magnetic fields up to 9 T. The validity of this method is tested by measuring various types of metallic (copper, platinum, and constantan) and insulating (SiO2) materials, which have a wide range of thermal conductivity values (1-400 W m-1 K-1). We have successfully employed this technique for measuring the thermal conductivity of two actinide single crystals: uranium dioxide and uranium nitride. This new experimental approach for studying nuclear materials will help us to advance reactor fuel development and understanding. We have also shown that this experimental setup can be adapted to the Physical Property Measurement System (Quantum Design) environment and/or other cryocooler systems.

Rotating disk electrode system for elevated pressures and temperatures.

PubMed

Fleige, M J; Wiberg, G K H; Arenz, M

2015-06-01

We describe the development and test of an elevated pressure and temperature rotating disk electrode (RDE) system that allows measurements under well-defined mass transport conditions. As demonstrated for the oxygen reduction reaction on polycrystalline platinum (Pt) in 0.5M H2SO4, the setup can easily be operated in a pressure range of 1-101 bar oxygen, and temperature of 140 °C. Under such conditions, diffusion limited current densities increase by almost two orders of magnitude as compared to conventional RDE setups allowing, for example, fuel cell catalyst studies under more realistic conditions. Levich plots demonstrate that the mass transport is indeed well-defined, i.e., at low electrode potentials, the measured current densities are fully diffusion controlled, while at higher potentials, a mixed kinetic-diffusion controlled regime is observed. Therefore, the setup opens up a new field for RDE investigations under temperature and current density conditions relevant for low and high temperature proton exchange membrane fuel cells.

Rotating disk electrode system for elevated pressures and temperatures

NASA Astrophysics Data System (ADS)

Fleige, M. J.; Wiberg, G. K. H.; Arenz, M.

2015-06-01

We describe the development and test of an elevated pressure and temperature rotating disk electrode (RDE) system that allows measurements under well-defined mass transport conditions. As demonstrated for the oxygen reduction reaction on polycrystalline platinum (Pt) in 0.5M H2SO4, the setup can easily be operated in a pressure range of 1-101 bar oxygen, and temperature of 140 °C. Under such conditions, diffusion limited current densities increase by almost two orders of magnitude as compared to conventional RDE setups allowing, for example, fuel cell catalyst studies under more realistic conditions. Levich plots demonstrate that the mass transport is indeed well-defined, i.e., at low electrode potentials, the measured current densities are fully diffusion controlled, while at higher potentials, a mixed kinetic-diffusion controlled regime is observed. Therefore, the setup opens up a new field for RDE investigations under temperature and current density conditions relevant for low and high temperature proton exchange membrane fuel cells.

Potential Damage to Flight Hardware from MIL-STD-462 CS02 Setup

NASA Technical Reports Server (NTRS)

Harris, Patrick K.; Block, Nathan F.

2002-01-01

The MIL-STD-462 CS02 conducted susceptibility test setup, performed during electromagnetic compatibility (EMC) testing, consists of an audio transformer with the secondary used as an inductor and a large capacitor. Together, these two components form an L-type low-pass filter to minimize the injected test signal input into the power source. Some flight hardware power input configurations are not compatible with this setup and break into oscillation when powered up. This can damage flight hardware and caused a catastrophic failure to an item tested in the Goddard Space Flight Center (GSFC) Large EMC Test Facility.

The spectral imaging facility: Setup characterization

DOE Office of Scientific and Technical Information (OSTI.GOV)

De Angelis, Simone, E-mail: simone.deangelis@iaps.inaf.it; De Sanctis, Maria Cristina; Manzari, Paola Olga

2015-09-15

The SPectral IMager (SPIM) facility is a laboratory visible infrared spectrometer developed to support space borne observations of rocky bodies of the solar system. Currently, this laboratory setup is used to support the DAWN mission, which is in its journey towards the asteroid 1-Ceres, and to support the 2018 Exo-Mars mission in the spectral investigation of the Martian subsurface. The main part of this setup is an imaging spectrometer that is a spare of the DAWN visible infrared spectrometer. The spectrometer has been assembled and calibrated at Selex ES and then installed in the facility developed at the INAF-IAPS laboratorymore » in Rome. The goal of SPIM is to collect data to build spectral libraries for the interpretation of the space borne and in situ hyperspectral measurements of planetary materials. Given its very high spatial resolution combined with the imaging capability, this instrument can also help in the detailed study of minerals and rocks. In this paper, the instrument setup is first described, and then a series of test measurements, aimed to the characterization of the main subsystems, are reported. In particular, laboratory tests have been performed concerning (i) the radiation sources, (ii) the reference targets, and (iii) linearity of detector response; the instrumental imaging artifacts have also been investigated.« less

Acquisition system testing with superfluid helium. [cryopumping for space

NASA Technical Reports Server (NTRS)

Anderson, John E.; Fester, Dale A.; Dipirro, Michael J.

1988-01-01

Minus one-g outflow tests were conducted with superfluid helium in conjunction with a thermomechanical pump setup in order to study the use of capillary acquisition systems for NASA's Superfluid Helium On-Orbit Transfer (SHOOT) flight experiment. Results show that both fine mesh screen and porous sponge systems are capable of supplying superfluid helium to the thermomechanical pump inlet against a one-g head up to 4 cm, fulfilling the SHOOT requirements. Sponge results were found to be reproducible, while the screen results were not.

Kinematic Validation of a Multi-Kinect v2 Instrumented 10-Meter Walkway for Quantitative Gait Assessments.

PubMed

Geerse, Daphne J; Coolen, Bert H; Roerdink, Melvyn

2015-01-01

Walking ability is frequently assessed with the 10-meter walking test (10MWT), which may be instrumented with multiple Kinect v2 sensors to complement the typical stopwatch-based time to walk 10 meters with quantitative gait information derived from Kinect's 3D body point's time series. The current study aimed to evaluate a multi-Kinect v2 set-up for quantitative gait assessments during the 10MWT against a gold-standard motion-registration system by determining between-systems agreement for body point's time series, spatiotemporal gait parameters and the time to walk 10 meters. To this end, the 10MWT was conducted at comfortable and maximum walking speed, while 3D full-body kinematics was concurrently recorded with the multi-Kinect v2 set-up and the Optotrak motion-registration system (i.e., the gold standard). Between-systems agreement for body point's time series was assessed with the intraclass correlation coefficient (ICC). Between-systems agreement was similarly determined for the gait parameters' walking speed, cadence, step length, stride length, step width, step time, stride time (all obtained for the intermediate 6 meters) and the time to walk 10 meters, complemented by Bland-Altman's bias and limits of agreement. Body point's time series agreed well between the motion-registration systems, particularly so for body points in motion. For both comfortable and maximum walking speeds, the between-systems agreement for the time to walk 10 meters and all gait parameters except step width was high (ICC ≥ 0.888), with negligible biases and narrow limits of agreement. Hence, body point's time series and gait parameters obtained with a multi-Kinect v2 set-up match well with those derived with a gold standard in 3D measurement accuracy. Future studies are recommended to test the clinical utility of the multi-Kinect v2 set-up to automate 10MWT assessments, thereby complementing the time to walk 10 meters with reliable spatiotemporal gait parameters obtained objectively in a quick, unobtrusive and patient-friendly manner.

Kinematic Validation of a Multi-Kinect v2 Instrumented 10-Meter Walkway for Quantitative Gait Assessments

PubMed Central

Geerse, Daphne J.; Coolen, Bert H.; Roerdink, Melvyn

2015-01-01

Walking ability is frequently assessed with the 10-meter walking test (10MWT), which may be instrumented with multiple Kinect v2 sensors to complement the typical stopwatch-based time to walk 10 meters with quantitative gait information derived from Kinect’s 3D body point’s time series. The current study aimed to evaluate a multi-Kinect v2 set-up for quantitative gait assessments during the 10MWT against a gold-standard motion-registration system by determining between-systems agreement for body point’s time series, spatiotemporal gait parameters and the time to walk 10 meters. To this end, the 10MWT was conducted at comfortable and maximum walking speed, while 3D full-body kinematics was concurrently recorded with the multi-Kinect v2 set-up and the Optotrak motion-registration system (i.e., the gold standard). Between-systems agreement for body point’s time series was assessed with the intraclass correlation coefficient (ICC). Between-systems agreement was similarly determined for the gait parameters’ walking speed, cadence, step length, stride length, step width, step time, stride time (all obtained for the intermediate 6 meters) and the time to walk 10 meters, complemented by Bland-Altman’s bias and limits of agreement. Body point’s time series agreed well between the motion-registration systems, particularly so for body points in motion. For both comfortable and maximum walking speeds, the between-systems agreement for the time to walk 10 meters and all gait parameters except step width was high (ICC ≥ 0.888), with negligible biases and narrow limits of agreement. Hence, body point’s time series and gait parameters obtained with a multi-Kinect v2 set-up match well with those derived with a gold standard in 3D measurement accuracy. Future studies are recommended to test the clinical utility of the multi-Kinect v2 set-up to automate 10MWT assessments, thereby complementing the time to walk 10 meters with reliable spatiotemporal gait parameters obtained objectively in a quick, unobtrusive and patient-friendly manner. PMID:26461498

Performing a Large-Scale Modal Test on the B2 Stand Crane at NASA's Stennis Space Center

NASA Technical Reports Server (NTRS)

Stasiunas, Eric C.; Parks, Russel A.; Sontag, Brendan D.

2018-01-01

A modal test of NASA's Space Launch System (SLS) Core Stage is scheduled to occur at the Stennis Space Center B2 test stand. A derrick crane with a 150-ft long boom, located at the top of the stand, will be used to suspend the Core Stage in order to achieve defined boundary conditions. During this suspended modal test, it is expected that dynamic coupling will occur between the crane and the Core Stage. Therefore, a separate modal test was performed on the B2 crane itself, in order to evaluate the varying dynamic characteristics and correlate math models of the crane. Performing a modal test on such a massive structure was challenging and required creative test setup and procedures, including implementing both AC and DC accelerometers, and performing both classical hammer and operational modal analysis. This paper describes the logistics required to perform this large-scale test, as well as details of the test setup, the modal test methods used, and an overview and application of the results.

Thermal diffusion forced Rayleigh scattering setup optimized for aqueous mixtures.

PubMed

Wiegand, Simone; Ning, Hui; Kriegs, Hartmut

2007-12-27

We developed a thermal diffusion forced Rayleigh scattering (TDFRS) setup operating at a writing wavelength of 980 nm, which corresponds to an absorption band of water with an absorption coefficient of approximately 0.5 cm(-1). Therefore, aqueous mixtures require no dye to convert the light into heat energy. Especially for aqueous system with a complex phase behavior such as surfactant systems, the addition of a water soluble dye can cause artifacts. The infrared-TDFRS (IR-TDFRS) setup has been validated for water/ethanol mixtures with water weight fractions c = 0.5-0.95 and in a temperature range between T = 15 degrees C to T = 35 degrees C. Comparison with literature data shows an excellent agreement. The addition of a small amount (c(dye) approximately 10(-6) wt) of adsorbing dye at the writing wavelength allows also the investigation of organic mixtures. We investigated the three binary mixtures of dodecane, isobutylbenzene, and 1,2,3,4-tetrahydronaphthalene at a weight fraction of c = 0.5 at a temperature of 25 degrees C and found good agreement with the Soret coefficients, which had been obtained in a benchmark test under the same conditions. Therefore, the presented setup is suitable for the investigation of the thermal diffusion behavior in aqueous and organic mixtures, and in the case of aqueous systems, the addition of a dye can be avoided.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bartlett, Roscoe A.; Baird, Mark L.; Berrill, Mark A.

This guide describes the structure and setup of the standard VERA development environment (VERA Dev Env) and standard VERA Third Party Libraries (TPLs) that need to be in place before installing many of the VERA simulation components. It describes everything from the initial setup on a new machine to the final build, testing, and installation of VERA components. The goal of this document is to describe how to create the directories and contents outlined in Standard VERA Dev Env Directory Structure and then obtain the remaining VERA source and build, test, and install any of the necessary VERA components onmore » a given system. This document describes the process both for a development version of VERA and for a released tarball of the VERA sources.« less

Prototype solar heating and combined heating and cooling systems

NASA Technical Reports Server (NTRS)

1977-01-01

Schedules and technical progress in the development of eight prototype solar heating and combined solar heating and cooling systems are reported. Particular emphasis is given to the analysis and preliminary design for the cooling subsystem, and the setup and testing of a horizontal thermal energy storage tank configuration and collector shroud evaluation.

Ultra high vacuum test setup for electron gun

NASA Astrophysics Data System (ADS)

Pandiyar, M. L.; Prasad, M.; Jain, S. K.; Kumar, R.; Hannurkar, P. R.

2008-05-01

Ultra High Vacuum (UHV) test setup for electron gun testing has been developed. The development of next generation light sources and accelerators require development of klystron as a radio frequency power source, and in turn electron gun. This UHV electron gun test setup can be used to test the electron guns ranging from high average current, quasi-continuous wave to high peak current, single pulse etc. An electron gun has been designed, fabricated, assembled and tested for insulation up to 80 kV under the programme to develop high power klystron for future accelerators. Further testing includes the electron emission parameters characterization of the cathode, as it determines the development of a reliable and efficient electron gun with high electron emission current and high life time as well. This needs a clean ultra high vacuum to study these parameters particularly at high emission current. The cathode emission current, work function and vapour pressure of cathode surface material at high temperature studies will further help in design and development of high power electron gun The UHV electron gun test setup consists of Turbo Molecular Pump (TMP), Sputter Ion Pump (SIP), pressure gauge, high voltage and cathode power supplies, current measurement device, solenoid magnet and its power supply, residual gas analyser etc. The ultimate vacuum less than 2×10-9 mbar was achieved. This paper describes the UHV test setup for electron gun testing.

Gas diffusion electrode setup for catalyst testing in concentrated phosphoric acid at elevated temperatures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wiberg, Gustav K. H., E-mail: gustav.wiberg@gmail.com, E-mail: m.arenz@chem.ku.dk; Fleige, Michael; Arenz, Matthias, E-mail: gustav.wiberg@gmail.com, E-mail: m.arenz@chem.ku.dk

2015-02-15

We present a detailed description of the construction and testing of an electrochemical cell setup allowing the investigation of a gas diffusion electrode containing carbon supported high surface area catalysts. The setup is designed for measurements in concentrated phosphoric acid at elevated temperature, i.e., very close to the actual conditions in high temperature proton exchange membrane fuel cells (HT-PEMFCs). The cell consists of a stainless steel flow field and a PEEK plastic cell body comprising the electrochemical cell, which exhibits a three electrode configuration. The cell body and flow field are braced using a KF-25 vacuum flange clamp, which allowsmore » an easy assembly of the setup. As demonstrated, the setup can be used to investigate temperature dependent electrochemical processes on high surface area type electrocatalysts, but it also enables quick screening tests of HT-PEMFC catalysts under realistic conditions.« less

Gas diffusion electrode setup for catalyst testing in concentrated phosphoric acid at elevated temperatures

NASA Astrophysics Data System (ADS)

Wiberg, Gustav K. H.; Fleige, Michael; Arenz, Matthias

2015-02-01

We present a detailed description of the construction and testing of an electrochemical cell setup allowing the investigation of a gas diffusion electrode containing carbon supported high surface area catalysts. The setup is designed for measurements in concentrated phosphoric acid at elevated temperature, i.e., very close to the actual conditions in high temperature proton exchange membrane fuel cells (HT-PEMFCs). The cell consists of a stainless steel flow field and a PEEK plastic cell body comprising the electrochemical cell, which exhibits a three electrode configuration. The cell body and flow field are braced using a KF-25 vacuum flange clamp, which allows an easy assembly of the setup. As demonstrated, the setup can be used to investigate temperature dependent electrochemical processes on high surface area type electrocatalysts, but it also enables quick screening tests of HT-PEMFC catalysts under realistic conditions.

Mechanical fatigue resistance of an implantable branched lead system for a distributed set of longitudinal intrafascicular electrodes

NASA Astrophysics Data System (ADS)

Pena, A. E.; Kuntaegowdanahalli, S. S.; Abbas, J. J.; Patrick, J.; Horch, K. W.; Jung, R.

2017-12-01

Objective. A neural interface system has been developed that consists of an implantable stimulator/recorder can with a 15-electrode lead that trifurcates into three bundles of five individual wire longitudinal intrafascicular electrodes. This work evaluated the mechanical fatigue resistance of the branched lead and distributed electrode system under conditions designed to mimic anticipated strain profiles that would be observed after implantation in the human upper arm. Approach. Custom test setups and procedures were developed to apply linear or angular strain at four critical stress riser points on the lead and electrode system. Each test was performed to evaluate fatigue under a high repetition/low amplitude paradigm designed to test the effects of arm movement on the leads during activities such as walking, or under a low repetition/high amplitude paradigm designed to test the effects of more strenuous upper arm activities. The tests were performed on representative samples of the implantable lead system for human use. The specimens were fabricated using procedures equivalent to those that will be used during production of human-use implants. Electrical and visual inspections of all test specimens were performed before and after the testing procedures to assess lead integrity. Main results. Measurements obtained before and after applying repetitive strain indicated that all test specimens retained electrical continuity and that electrical impedance remained well below pre-specified thresholds for detection of breakage. Visual inspection under a microscope at 10×  magnification did not reveal any signs of damage to the wires or silicone sheathing at the stress riser points. Significance. These results demonstrate that the branched lead of this implantable neural interface system has sufficient mechanical fatigue resistance to withstand strain profiles anticipated when the system is implanted in an arm. The novel test setups and paradigms may be useful in testing other lead systems.

Qualified measurement setup of polarization extinction ratio for Panda PMF with LC/UPC connector

NASA Astrophysics Data System (ADS)

Thongdaeng, Rutsuda; Worasucheep, Duang-rudee; Ngiwprom, Adisak

2018-03-01

Polarization Extinction Ratio (PER) is one of the key parameters for Polarization Maintaining Fiber (PMF) connector. Based on our previous studies, the bending radius of fiber greater than 1.5 cm will not affect the insertion loss of PMF [1]. Moreover, the measured PER of Panda PMF with LC/UPC connectors is more stable when that PMF is coiled around a hot rod with a minimum of 3-cm in diameter at 75°C temperature [2]. Hence, the hot rod with less constrained 6-cm in diameter at constant 75°C was selected for this PER measurement. Two PER setups were verified and compared for measuring LC/UPC PMF connectors. The Polarized Laser Source (PLS) at 1550 nm wavelength and PER meter from OZ Optics were used in both setups, in which the measured connector was connected to PLS at 0° angle while the other end was connected to PER meter. In order to qualify our setups, the percentage of Repeatability and Reproducibility (%R&R) were tested and calculated. In each setup, the PER measurement was repeated 3 trials by 3 appraisers using 10 LC/UPC PMF connectors (5 LC/UPC PMF patchcords with 3.5+/-0.5 meters in length) in random order. The 1st setup, PMF was coiled at a larger 20-cm diameter for 3 to 5 loops and left in room temperature during the test. The 2nd setup, PMF was coiled around a hot rod at constant 75°C with 6-cm diameter for 8 to 10 loops for at least 5 minutes before testing. There are 3 ranges of %R&R acceptation guide line: <10% is acceptable, between 10% - 30% is marginal, and <30% is unacceptable. According to our results, the %R&R of the 1st PER test setup was 16.2% as marginality, and the 2nd PER test setup was 8.9% as acceptance. Thus, providing the better repeatability and reproducibility, this 2nd PER test setup having PMF coiled around a hot rod at constant 75°C with 6-cm diameter was selected for our next study of the impact of hot temperature on PER in LC/UPC PMF connector.

Infant multiple breath washout using a new commercially available device: Ready to replace the previous setup?

PubMed

Kentgens, Anne-Christianne; Guidi, Marisa; Korten, Insa; Kohler, Lena; Binggeli, Severin; Singer, Florian; Latzin, Philipp; Anagnostopoulou, Pinelopi

2018-05-01

Multiple breath washout (MBW) is a sensitive test to measure lung volumes and ventilation inhomogeneity from infancy on. The commonly used setup for infant MBW, based on ultrasonic flowmeter, requires extensive signal processing, which may reduce robustness. A new setup may overcome some previous limitations but formal validation is lacking. We assessed the feasibility of infant MBW testing with the new setup and compared functional residual capacity (FRC) values of the old and the new setup in vivo and in vitro. We performed MBW in four healthy infants and four infants with cystic fibrosis, as well as in a Plexiglas lung simulator using realistic lung volumes and breathing patterns, with the new (Exhalyzer D, Spiroware 3.2.0, Ecomedics) and the old setup (Exhalyzer D, WBreath 3.18.0, ndd) in random sequence. The technical feasibility of MBW with the new device-setup was 100%. Intra-subject variability in FRC was low in both setups, but differences in FRC between the setups were considerable (mean relative difference 39.7%, range 18.9; 65.7, P = 0.008). Corrections of software settings decreased FRC differences (14.0%, -6.4; 42.3, P = 0.08). Results were confirmed in vitro. MBW measurements with the new setup were feasible in infants. However, despite attempts to correct software settings, outcomes between setups were not interchangeable. Further work is needed before widespread application of the new setup can be recommended. © 2018 Wiley Periodicals, Inc.

Potential Damage to Flight Hardware from MIL-STD-462 CS02 Setup

NASA Technical Reports Server (NTRS)

Harris, Patrick K.; Block, Nathan F.

2003-01-01

The MIL-STD-462 CS02 conducted susceptibility test setup includes an audio transformer, with the secondary used as an inductor, and a large capacitor. Together, these two components form an L-type low-pass filter to minimize the injected test signal input into the power source. Some flight hardware power input configurations are not compatible with this setup and break into oscillation when powered up. This, in turn, can damage flight hardware. Such an oscillation resulted in the catastrophic failure of an item tested in the Goddard Space Flight Center (GSFC) Large electromagnetic compatibility (EMC) Test Facility.

3D digital image correlation using single color camera pseudo-stereo system

NASA Astrophysics Data System (ADS)

Li, Junrui; Dan, Xizuo; Xu, Wan; Wang, Yonghong; Yang, Guobiao; Yang, Lianxiang

2017-10-01

Three dimensional digital image correlation (3D-DIC) has been widely used by industry to measure the 3D contour and whole-field displacement/strain. In this paper, a novel single color camera 3D-DIC setup, using a reflection-based pseudo-stereo system, is proposed. Compared to the conventional single camera pseudo-stereo system, which splits the CCD sensor into two halves to capture the stereo views, the proposed system achieves both views using the whole CCD chip and without reducing the spatial resolution. In addition, similarly to the conventional 3D-DIC system, the center of the two views stands in the center of the CCD chip, which minimizes the image distortion relative to the conventional pseudo-stereo system. The two overlapped views in the CCD are separated by the color domain, and the standard 3D-DIC algorithm can be utilized directly to perform the evaluation. The system's principle and experimental setup are described in detail, and multiple tests are performed to validate the system.

Stable thermophoretic trapping of generic particles at low pressures

NASA Astrophysics Data System (ADS)

Fung, Long Fung Frankie

2017-04-01

We demonstrate levitation and three-dimensionally stable trapping of a wide variety of particles in medium vacuum through thermophoresis. Typical sizes of the trapped particles are between 10 μm and 1 mm; air pressure is between 1 and 10 Torr. We describe the experimental setup used to produce the temperature gradient, as well as our procedure for introducing particles into the experimental setup. To determine the levitation force and test various theoretical models, we examine the levitation heights of spherical polyethylene spheres under various conditions. A good agreement with two theoretical models is concluded. Our system offers a platform to discover various thermophoretic phenomena and to simulate dynamics of interacting many-body systems in a microgravity environment. NSF MRSEC Grant No. DMR-1420709.

Lowering the Barrier for Standards-Compliant and Discoverable Hydrological Data Publication

NASA Astrophysics Data System (ADS)

Kadlec, J.

2013-12-01

The growing need for sharing and integration of hydrological and climate data across multiple organizations has resulted in the development of distributed, services-based, standards-compliant hydrological data management and data hosting systems. The problem with these systems is complicated set-up and deployment. Many existing systems assume that the data publisher has remote-desktop access to a locally managed server and experience with computer network setup. For corporate websites, shared web hosting services with limited root access provide an inexpensive, dynamic web presence solution using the Linux, Apache, MySQL and PHP (LAMP) software stack. In this paper, we hypothesize that a webhosting service provides an optimal, low-cost solution for hydrological data hosting. We propose a software architecture of a standards-compliant, lightweight and easy-to-deploy hydrological data management system that can be deployed on the majority of existing shared internet webhosting services. The architecture and design is validated by developing Hydroserver Lite: a PHP and MySQL-based hydrological data hosting package that is fully standards-compliant and compatible with the Consortium of Universities for Advancement of Hydrologic Sciences (CUAHSI) hydrologic information system. It is already being used for management of field data collection by students of the McCall Outdoor Science School in Idaho. For testing, the Hydroserver Lite software has been installed on multiple different free and low-cost webhosting sites including Godaddy, Bluehost and 000webhost. The number of steps required to set-up the server is compared with the number of steps required to set-up other standards-compliant hydrologic data hosting systems including THREDDS, IstSOS and MapServer SOS.

Cooperative Search by UAV Teams: A Model Predictive Approach Using Dynamic Graphs

DTIC Science & Technology

2011-10-01

decentralized processing and control architecture. SLAMEM asset models accurately represent the Unicorn UAV platforms and other standard military platforms in...IMPLEMENTATION The CGBMPS algorithm has been successfully field-tested using both Unicorn [27] and Raven [20] UAV platforms. This section describes...the hardware-software system setup and implementation used for testing with Unicorns , Toyon’s UAV test platform. We also present some results from the

How-to-Do-It. Hydroponics and Aquaculture in the High School Classroom.

ERIC Educational Resources Information Center

Nicol, Ernest

1990-01-01

The construction of a hydroponic system for use in the classroom is described. Provided are construction details, a list of materials with approximate cost, a diagram of the setup, and a sample test. Several activities are suggested. (CW)

Multi-parameter fibre Bragg grating sensor-array for thermal vacuum cycling test

NASA Astrophysics Data System (ADS)

Cheng, L.; Ahlers, B.; Toet, P.; Casarosa, G.; Appolloni, M.

2017-11-01

Fibre Bragg Grating (FBG) sensor systems based on optical fibres are gaining interest in space applications. Studies on Structural Health Monitoring (SHM) of the reusable launchers using FBG sensors have been carried out in the Future European Space Transportation Investigations Programme (FESTIP). Increasing investment in the development on FBG sensor applications is foreseen for the Future Launchers Preparatory Programme (FLPP). TNO has performed different SHM measurements with FBGs including on the VEGA interstage [1, 2] in 2006. Within the current project, a multi-parameter FBG sensor array demonstrator system for temperature and strain measurements is designed, fabricated and tested under ambient as well as Thermal Vacuum (TV) conditions in a TV chamber of the European Space Agency (ESA), ESTEC site. The aim is the development of a multi-parameters measuring system based on FBG technology for space applications. During the TV tests of a Space Craft (S/C) or its subsystems, thermal measurements, as well as strain measurements are needed by the engineers in order to verify their prediction and to validate their models. Because of the dimensions of the test specimen and the accuracy requested to the measurement, a large number of observation/measuring points are needed. Conventional sensor systems require a complex routing of the cables connecting the sensors to their acquisition unit. This will add extra weight to the construction under test. FBG sensors are potentially light-weight and can easily be multiplexed in an array configuration. The different tasks comply of a demonstrator system design; its component selection, procurement, manufacturing and finally its assembly. The temperature FBG sensor is calibrated in a dedicated laboratory setup down to liquid nitrogen (LN2) temperature at TNO. A temperature-wavelength calibration curve is generated. After a test programme definition a setup in thermal vacuum is realised at ESA premises including a mechanical strain transducer to generate strain via a dedicated feed through in the chamber. Thermocouples are used to log the temperature for comparison to the temperature FBG sensor. Extreme temperature ranges from -150°C and +70°C at a pressure down to 10-4 Pa (10-6 mbar) are covered as well as testing under ambient conditions. In total five thermal cycles during a week test are performed. The FBG temperature sensor test results performed in the ESA/ESTEC TV chamber reveal high reproducibility (within 1 °C) within the test temperature range without any evidence of hysteresis. Differences are detected to the previous calibration curve. Investigation is performed to find the cause of the discrepancy. Differences between the test set-ups are identified. Equipment of the TNO test is checked and excluded to be the cause. Additional experiments are performed. The discrepancy is most likely caused by a 'thermal shock' due to rapid cooling down to LN2 temperature, which results in a wavelength shift. Test data of the FBG strain sensor is analysed. The read-out of the FBG strain sensor varies with the temperature during the test. This can be caused by temperature induced changes in the mechanical setup (fastening of the mechanical parts) or impact of temperature to the mechanical strain transfer to the FBG. Improvements are identified and recommendations given for future activities.

Digital image compression for a 2f multiplexing optical setup

NASA Astrophysics Data System (ADS)

Vargas, J.; Amaya, D.; Rueda, E.

2016-07-01

In this work a virtual 2f multiplexing system was implemented in combination with digital image compression techniques and redundant information elimination. Depending on the image type to be multiplexed, a memory-usage saving of as much as 99% was obtained. The feasibility of the system was tested using three types of images, binary characters, QR codes, and grey level images. A multiplexing step was implemented digitally, while a demultiplexing step was implemented in a virtual 2f optical setup following real experimental parameters. To avoid cross-talk noise, each image was codified with a specially designed phase diffraction carrier that would allow the separation and relocation of the multiplexed images on the observation plane by simple light propagation. A description of the system is presented together with simulations that corroborate the method. The present work may allow future experimental implementations that will make use of all the parallel processing capabilities of optical systems.

Application of Particle Swarm Optimization in Computer Aided Setup Planning

NASA Astrophysics Data System (ADS)

Kafashi, Sajad; Shakeri, Mohsen; Abedini, Vahid

2011-01-01

New researches are trying to integrate computer aided design (CAD) and computer aided manufacturing (CAM) environments. The role of process planning is to convert the design specification into manufacturing instructions. Setup planning has a basic role in computer aided process planning (CAPP) and significantly affects the overall cost and quality of machined part. This research focuses on the development for automatic generation of setups and finding the best setup plan in feasible condition. In order to computerize the setup planning process, three major steps are performed in the proposed system: a) Extraction of machining data of the part. b) Analyzing and generation of all possible setups c) Optimization to reach the best setup plan based on cost functions. Considering workshop resources such as machine tool, cutter and fixture, all feasible setups could be generated. Then the problem is adopted with technological constraints such as TAD (tool approach direction), tolerance relationship and feature precedence relationship to have a completely real and practical approach. The optimal setup plan is the result of applying the PSO (particle swarm optimization) algorithm into the system using cost functions. A real sample part is illustrated to demonstrate the performance and productivity of the system.

An Automatic Image Processing Workflow for Daily Magnetic Resonance Imaging Quality Assurance.

PubMed

Peltonen, Juha I; Mäkelä, Teemu; Sofiev, Alexey; Salli, Eero

2017-04-01

The performance of magnetic resonance imaging (MRI) equipment is typically monitored with a quality assurance (QA) program. The QA program includes various tests performed at regular intervals. Users may execute specific tests, e.g., daily, weekly, or monthly. The exact interval of these measurements varies according to the department policies, machine setup and usage, manufacturer's recommendations, and available resources. In our experience, a single image acquired before the first patient of the day offers a low effort and effective system check. When this daily QA check is repeated with identical imaging parameters and phantom setup, the data can be used to derive various time series of the scanner performance. However, daily QA with manual processing can quickly become laborious in a multi-scanner environment. Fully automated image analysis and results output can positively impact the QA process by decreasing reaction time, improving repeatability, and by offering novel performance evaluation methods. In this study, we have developed a daily MRI QA workflow that can measure multiple scanner performance parameters with minimal manual labor required. The daily QA system is built around a phantom image taken by the radiographers at the beginning of day. The image is acquired with a consistent phantom setup and standardized imaging parameters. Recorded parameters are processed into graphs available to everyone involved in the MRI QA process via a web-based interface. The presented automatic MRI QA system provides an efficient tool for following the short- and long-term stability of MRI scanners.

A Flexible Pilot-Scale Setup for Real-Time Studies in Process Systems Engineering

ERIC Educational Resources Information Center

Panjapornpon, Chanin; Fletcher, Nathan; Soroush, Masoud

2006-01-01

This manuscript describes a flexible, pilot-scale setup that can be used for training students and carrying out research in process systems engineering. The setup allows one to study a variety of process systems engineering concepts such as design feasibility, design flexibility, control configuration selection, parameter estimation, process and…

Synthetic depth data creation for sensor setup planning and evaluation of multi-camera multi-person trackers

NASA Astrophysics Data System (ADS)

Pattke, Marco; Martin, Manuel; Voit, Michael

2017-05-01

Tracking people with cameras in public areas is common today. However with an increasing number of cameras it becomes harder and harder to view the data manually. Especially in safety critical areas automatic image exploitation could help to solve this problem. Setting up such a system can however be difficult because of its increased complexity. Sensor placement is critical to ensure that people are detected and tracked reliably. We try to solve this problem using a simulation framework that is able to simulate different camera setups in the desired environment including animated characters. We combine this framework with our self developed distributed and scalable system for people tracking to test its effectiveness and can show the results of the tracking system in real time in the simulated environment.

Accuracy and efficiency of an infrared based positioning and tracking system for patient set-up and monitoring in image guided radiotherapy

NASA Astrophysics Data System (ADS)

Jia, Jing; Xu, Gongming; Pei, Xi; Cao, Ruifen; Hu, Liqin; Wu, Yican

2015-03-01

An infrared based positioning and tracking (IPT) system was introduced and its accuracy and efficiency for patient setup and monitoring were tested for daily radiotherapy treatment. The IPT system consists of a pair of floor mounted infrared stereoscopic cameras, passive infrared markers and tools used for acquiring localization information as well as a custom controlled software which can perform the positioning and tracking functions. The evaluation of IPT system characteristics was conducted based on the AAPM 147 task report. Experiments on spatial drift and reproducibility as well as static and dynamic localization accuracy were carried out to test the efficiency of the IPT system. Measurements of known translational (up to 55.0 mm) set-up errors in three dimensions have been performed on a calibration phantom. The accuracy of positioning was evaluated on an anthropomorphic phantom with five markers attached to the surface; the precision of the tracking ability was investigated through a sinusoidal motion platform. For the monitoring of the respiration, three volunteers contributed to the breathing testing in real time. The spatial drift of the IPT system was 0.65 mm within 60 min to be stable. The reproducibility of position variations were between 0.01 and 0.04 mm. The standard deviation of static marker localization was 0.26 mm. The repositioning accuracy was 0.19 mm, 0.29 mm, and 0.53 mm in the left/right (L/R), superior/inferior (S/I) and anterior/posterior (A/P) directions, respectively. The measured dynamic accuracy was 0.57 mm and discrepancies measured for the respiratory motion tracking was better than 1 mm. The overall positioning accuracy of the IPT system was within 2 mm. In conclusion, the IPT system is an accurate and effective tool for assisting patient positioning in the treatment room. The characteristics of the IPT system can successfully meet the needs for real time external marker tracking and patient positioning as well as respiration monitoring during image guided radiotherapy treatments.

Simulator with integrated HW and SW for prediction of thermal comfort to provide feedback to the climate control system

NASA Astrophysics Data System (ADS)

Pokorný, Jan; Kopečková, Barbora; Fišer, Jan; JÍcha, Miroslav

2018-06-01

The aim of the paper is to assemble a simulator for evaluation of thermal comfort in car cabins in order to give a feedback to the HVAC (heating, ventilation and air conditioning) system. The HW (hardware) part of simulator is formed by thermal manikin Newton and RH (relative humidity), velocity and temperature probes. The SW (software) part consists of the Thermal Comfort Analyser (using ISO 14505-2) and Virtual Testing Stand of Car Cabin defining the heat loads of car cabin. Simulator can provide recommendation for the climate control how to improve thermal comfort in cabin by distribution and directing of air flow, and also by amount of ventilation power to keep optimal temperature inside a cabin. The methods of evaluation of thermal comfort were verified by tests with 10 test subjects for summer (summer clothing, ambient air temperature 30 °C, HVAC setup: +24 °C auto) and winter conditions (winter clothing, ambient air temperature -5 °C, HVAC setup: +18 °C auto). The tests confirmed the validity of the thermal comfort evaluation using the thermal manikin and ISO 14505-2.

Apollo Contour Rocket Nozzle in the Propulsion Systems Laboratory

NASA Image and Video Library

1964-07-21

Bill Harrison and Bud Meilander check the setup of an Apollo Contour rocket nozzle in the Propulsion Systems Laboratory at the National Aeronautics and Space Administration (NASA) Lewis Research Center. The Propulsion Systems Laboratory contained two 14-foot diameter test chambers that could simulate conditions found at very high altitudes. The facility was used in the 1960s to study complex rocket engines such as the Pratt and Whitney RL-10 and rocket components such as the Apollo Contour nozzle, seen here. Meilander oversaw the facility’s mechanics and the installation of test articles into the chambers. Harrison was head of the Supersonic Tunnels Branch in the Test Installations Division. Researchers sought to determine the impulse value of the storable propellant mix, classify and improve the internal engine performance, and compare the results with analytical tools. A special setup was installed in the chamber that included a device to measure the thrust load and a calibration stand. Both cylindrical and conical combustion chambers were examined with the conical large area ratio nozzles. In addition, two contour nozzles were tested, one based on the Apollo Service Propulsion System and the other on the Air Force’s Titan transtage engine. Three types of injectors were investigated, including a Lewis-designed model that produced 98-percent efficiency. It was determined that combustion instability did not affect the nozzle performance. Although much valuable information was obtained during the tests, attempts to improve the engine performance were not successful.

Quantum transport in coupled Majorana box systems

NASA Astrophysics Data System (ADS)

Gau, Matthias; Plugge, Stephan; Egger, Reinhold

2018-05-01

We present a theoretical analysis of low-energy quantum transport in coupled Majorana box devices. A single Majorana box represents a Coulomb-blockaded mesoscopic superconductor proximitizing two or more long topological nanowires. The box thus harbors at least four Majorana zero modes (MZMs). Setups with several Majorana boxes, where MZMs on different boxes are tunnel coupled via short nanowire segments, are key ingredients to recent Majorana qubit and code network proposals. We construct and study the low-energy theory for multiterminal junctions with normal leads connected to the coupled box device by lead-MZM tunnel contacts. Transport experiments in such setups can test the nonlocality of Majorana-based systems and the integrity of the underlying Majorana qubits. For a single box, we recover the previously described topological Kondo effect which can be captured by a purely bosonic theory. For several coupled boxes, however, nonconserved local fermion parities require the inclusion of additional local sets of Pauli operators. We present a renormalization group analysis and develop a nonperturbative strong-coupling approach to quantum transport in such systems. Our findings are illustrated for several examples, including a loop qubit device and different two-box setups.

Configuration and Sizing of a Test Fixture for Panels Under Combined Loads

NASA Technical Reports Server (NTRS)

Lovejoy, Andrew E.

2006-01-01

Future air and space structures are expected to utilize composite panels that are subjected to combined mechanical loads, such as bi-axial compression/tension, shear and pressure. Therefore, the ability to accurately predict the buckling and strength failures of such panels is important. While computational analysis can provide tremendous insight into panel response, experimental results are necessary to verify predicted performances of these panels to judge the accuracy of computational methods. However, application of combined loads is an extremely difficult task due to the complex test fixtures and set-up required. Presented herein is a comparison of several test set-ups capable of testing panels under combined loads. Configurations compared include a D-box, a segmented cylinder and a single panel set-up. The study primarily focuses on the preliminary sizing of a single panel test configuration capable of testing flat panels under combined in-plane mechanical loads. This single panel set-up appears to be best suited to the testing of both strength critical and buckling critical panels. Required actuator loads and strokes are provided for various square, flat panels.

On-field mounting position estimation of a lidar sensor

NASA Astrophysics Data System (ADS)

Khan, Owes; Bergelt, René; Hardt, Wolfram

2017-10-01

In order to retrieve a highly accurate view of their environment, autonomous cars are often equipped with LiDAR sensors. These sensors deliver a three dimensional point cloud in their own co-ordinate frame, where the origin is the sensor itself. However, the common co-ordinate system required by HAD (Highly Autonomous Driving) software systems has its origin at the center of the vehicle's rear axle. Thus, a transformation of the acquired point clouds to car co-ordinates is necessary, and thereby the determination of the exact mounting position of the LiDAR system in car coordinates is required. Unfortunately, directly measuring this position is a time-consuming and error-prone task. Therefore, different approaches have been suggested for its estimation which mostly require an exhaustive test-setup and are again time-consuming to prepare. When preparing a high number of LiDAR mounted test vehicles for data acquisition, most approaches fall short due to time or money constraints. In this paper we propose an approach for mounting position estimation which features an easy execution and setup, thus making it feasible for on-field calibration.

High-resolution continuous flow analysis setup for water isotopic measurement from ice cores using laser spectroscopy

NASA Astrophysics Data System (ADS)

Emanuelsson, B. D.; Baisden, W. T.; Bertler, N. A. N.; Keller, E. D.; Gkinis, V.

2014-12-01

Here we present an experimental setup for water stable isotopes (δ18O and δD) continuous flow measurements. It is the first continuous flow laser spectroscopy system that is using Off-Axis Integrated Cavity Output Spectroscopy (OA-ICOS; analyzer manufactured by Los Gatos Research - LGR) in combination with an evaporation unit to continuously analyze sample from an ice core. A Water Vapor Isotopic Standard Source (WVISS) calibration unit, manufactured by LGR, was modified to: (1) increase the temporal resolution by reducing the response time (2) enable measurements on several water standards, and (3) to reduce the influence from memory effects. While this setup was designed for the Continuous Flow Analysis (CFA) of ice cores, it can also continuously analyze other liquid or vapor sources. The modified setup provides a shorter response time (~54 and 18 s for 2013 and 2014 setup, respectively) compared to the original WVISS unit (~62 s), which is an improvement in measurement resolution. Another improvement compared to the original WVISS is that the modified setup has a reduced memory effect. Stability tests comparing the modified WVISS and WVISS setups were performed and Allan deviations (σAllan) were calculated to determine precision at different averaging times. For the 2013 modified setup the precision after integration times of 103 s are 0.060 and 0.070‰ for δ18O and δD, respectively. For the WVISS setup the corresponding σAllan values are 0.030, 0.060 and 0.043‰ for δ18O, δD and δ17O, respectively. For the WVISS setup the precision is 0.035, 0.070 and 0.042‰ after 103 s for δ18O, δD and δ17O, respectively. Both the modified setups and WVISS setup are influenced by instrumental drift with δ18O being more drift sensitive than δD. The σAllan values for δ18O of 0.30 and 0.18‰ for the modified (2013) and WVISS setup, respectively after averaging times of 104 s (2.78 h). The Isotopic Water Analyzer (IWA)-modified WVISS setup used during the 2013 Roosevelt Island Climate Evolution (RICE) ice core processing campaign achieved high precision measurements, in particular for δD, with high temporal resolution for the upper part of the core, where a seasonally resolved isotopic signal is preserved.

Recent progress of the Laser-driven Ion-beam Trace Probe

NASA Astrophysics Data System (ADS)

Yang, Xiaoyi; Xiao, Chijie; Chen, Yihang; Xu, Tianchao; Yu, Yi; Xu, Min; Wang, Long; Lin, Chen; Wang, Xiaogang

2017-10-01

The Laser-driven Ion-beam Trace Probe (LITP) is a new method to diagnose the poloidal magnetic field and radial electric field in tokamaks. Recently significant progresses have been made as follows. 1) The experimental system has been set up on the PKU Plasma Test (PPT) linear device and begun to validate the principle of LITP, including the ion source, the ion detector and the poloidal magnetic field cable. Preliminary experimental results matched the theoretical prediction well. 2) The reconstruction principle has been improved including the nonlinear effect. 3) Tomography methods have been applied in the reconstruction codes. Now the laser-driven ion-beam accelerator has been setup on the PPT device, and further test of LITP will start soon. After that a prototype of LITP system will be designed and setup on the HL-2A tokamak device. This work was supported by the CHINA MOST under 2012YQ030142, ITER-CHINA program 2015GB120001 and National Natural Science Foundation of China under 11575014 and 11375053.

Acoustic Noise Levels of Dental Equipments and Its Association with Fear and Annoyance Levels among Patients Attending Different Dental Clinic Setups in Jaipur, India

PubMed Central

Ganta, Shravani; Nagaraj, Anup; Pareek, Sonia; Atri, Mansi; Singh, Kushpal; Sidiq, Mohsin

2014-01-01

Background: Noise is a source of pervasive occupational hazard for practicing dentists and the patients. The sources of dental sounds by various dental equipments can pose as a potential hazard to hearing system and add to the annoyance levels of the patients. The aim of the study was to analyze the noise levels from various equipments and evaluate the effect of acoustic noise stimulus on dental fear and annoyance levels among patients attending different dental clinic setups in Jaipur, India. Methodology: The sampling frame comprised of 180 patients, which included 90 patients attending 10 different private clinics and 90 patients attending a Dental College in Jaipur. The levels of Acoustic Noise Stimulus originating from different equipments were determined using a precision sound level meter/decibulometer. Dental fear among patients was measured using Dental Fear Scale (DFS). Results: Statistical analysis was performed using chi square test and unpaired t-test. The mean background noise levels were found to be maximum in the pre-clinical setup/ laboratory areas (69.23+2.20). Females and the patients attending dental college setup encountered more fear on seeing the drill as compared to the patients attending private clinics (p<0.001). Conclusion: The sources of dental sounds can pose as a potential hazard to hearing system. It was analyzed that the environment in the clinics can directly have an effect on the fear and annoyance levels of patients. Hence it is necessary control the noise from various dental equipments to reduce the fear of patients from visiting a dental clinic. PMID:24959512

Force Limit System

NASA Technical Reports Server (NTRS)

Pawlik, Ralph; Krause, David; Bremenour, Frank

2011-01-01

The Force Limit System (FLS) was developed to protect test specimens from inadvertent overload. The load limit value is fully adjustable by the operator and works independently of the test system control as a mechanical (non-electrical) device. When a test specimen is loaded via an electromechanical or hydraulic test system, a chance of an overload condition exists. An overload applied to a specimen could result in irreparable damage to the specimen and/or fixturing. The FLS restricts the maximum load that an actuator can apply to a test specimen. When testing limited-run test articles or using very expensive fixtures, the use of such a device is highly recommended. Test setups typically use electronic peak protection, which can be the source of overload due to malfunctioning components or the inability to react quickly enough to load spikes. The FLS works independently of the electronic overload protection.

A Laboratory Test Setup for in Situ Measurements of the Dielectric Properties of Catalyst Powder Samples under Reaction Conditions by Microwave Cavity Perturbation: Set up and Initial Tests

PubMed Central

Dietrich, Markus; Rauch, Dieter; Porch, Adrian; Moos, Ralf

2014-01-01

The catalytic behavior of zeolite catalysts for the ammonia-based selective catalytic reduction (SCR) of nitrogen oxides (NOX) depends strongly on the type of zeolite material. An essential precondition for SCR is a previous ammonia gas adsorption that occurs on acidic sites of the zeolite. In order to understand and develop SCR active materials, it is crucial to know the amount of sorbed ammonia under reaction conditions. To support classical temperature-programmed desorption (TPD) experiments, a correlation of the dielectric properties with the catalytic properties and the ammonia sorption under reaction conditions appears promising. In this work, a laboratory test setup, which enables direct measurements of the dielectric properties of catalytic powder samples under a defined gas atmosphere and temperature by microwave cavity perturbation, has been developed. Based on previous investigations and computational simulations, a resonator cavity and a heating system were designed, installed and characterized. The resonator cavity is designed to operate in its TM010 mode at 1.2 GHz. The first measurement of the ammonia loading of an H-ZSM-5 zeolite confirmed the operating performance of the test setup at constant temperatures of up to 300 °C. It showed how both real and imaginary parts of the relative complex permittivity are strongly correlated with the mass of stored ammonia. PMID:25211199

A laboratory test setup for in situ measurements of the dielectric properties of catalyst powder samples under reaction conditions by microwave cavity perturbation: set up and initial tests.

PubMed

Dietrich, Markus; Rauch, Dieter; Porch, Adrian; Moos, Ralf

2014-09-10

The catalytic behavior of zeolite catalysts for the ammonia-based selective catalytic reduction (SCR) of nitrogen oxides (NOX) depends strongly on the type of zeolite material. An essential precondition for SCR is a previous ammonia gas adsorption that occurs on acidic sites of the zeolite. In order to understand and develop SCR active materials, it is crucial to know the amount of sorbed ammonia under reaction conditions. To support classical temperature-programmed desorption (TPD) experiments, a correlation of the dielectric properties with the catalytic properties and the ammonia sorption under reaction conditions appears promising. In this work, a laboratory test setup, which enables direct measurements of the dielectric properties of catalytic powder samples under a defined gas atmosphere and temperature by microwave cavity perturbation, has been developed. Based on previous investigations and computational simulations, a resonator cavity and a heating system were designed, installed and characterized. The resonator cavity is designed to operate in its TM010 mode at 1.2 GHz. The first measurement of the ammonia loading of an H-ZSM-5 zeolite confirmed the operating performance of the test setup at constant temperatures of up to 300 °C. It showed how both real and imaginary parts of the relative complex permittivity are strongly correlated with the mass of stored ammonia.

International Aerospace and Ground Conference on Lightning and Static Electricity (8th): Lightning Technology Roundup, held at Fort Worth, Texas on 21-23 June 1983.

DTIC Science & Technology

1983-06-01

fighter aircraft. The entire test bed is from testing of a representative digital supported above the ground plane by non - control system(s)l e.g... control and Increased systems Integration a. Raw data must be collected and Introduce new requirements for protection, experimental setups and An accurate...presented, several possible solutions to the grounding prob! - are suggested. All rely on establishing initial ground contact through a controlled non -zero

Design of experimental setup for supercritical CO2 jet under high ambient pressure conditions

NASA Astrophysics Data System (ADS)

Shi, Huaizhong; Li, Gensheng; He, Zhenguo; Wang, Haizhu; Zhang, Shikun

2016-12-01

With the commercial extraction of hydrocarbons in shale and tight reservoirs, efficient methods are needed to accelerate developing process. Supercritical CO2 (SC-CO2) jet has been considered as a potential way due to its unique fluid properties. In this article, a new setup is designed for laboratory experiment to research the SC-CO2 jet's characteristics in different jet temperatures, pressures, standoff distances, ambient pressures, etc. The setup is composed of five modules, including SC-CO2 generation system, pure SC-CO2 jet system, abrasive SC-CO2 jet system, CO2 recovery system, and data acquisition system. Now, a series of rock perforating (or case cutting) experiments have been successfully conducted using the setup about pure and abrasive SC-CO2 jet, and the results have proven the great perforating efficiency of SC-CO2 jet and the applications of this setup.

Design of experimental setup for supercritical CO2 jet under high ambient pressure conditions.

PubMed

Shi, Huaizhong; Li, Gensheng; He, Zhenguo; Wang, Haizhu; Zhang, Shikun

2016-12-01

With the commercial extraction of hydrocarbons in shale and tight reservoirs, efficient methods are needed to accelerate developing process. Supercritical CO 2 (SC-CO 2 ) jet has been considered as a potential way due to its unique fluid properties. In this article, a new setup is designed for laboratory experiment to research the SC-CO 2 jet's characteristics in different jet temperatures, pressures, standoff distances, ambient pressures, etc. The setup is composed of five modules, including SC-CO 2 generation system, pure SC-CO 2 jet system, abrasive SC-CO 2 jet system, CO 2 recovery system, and data acquisition system. Now, a series of rock perforating (or case cutting) experiments have been successfully conducted using the setup about pure and abrasive SC-CO 2 jet, and the results have proven the great perforating efficiency of SC-CO 2 jet and the applications of this setup.

Integrated Power, Avionics, and Software (iPAS) Space Telecommunications Radio System (STRS) Radio User's Guide -- Advanced Exploration Systems (AES)

NASA Technical Reports Server (NTRS)

Roche, Rigoberto; Shalkhauser, Mary Jo Windmille

2017-01-01

The Integrated Power, Avionics and Software (IPAS) software defined radio (SDR) was implemented on the Reconfigurable, Intelligently-Adaptive Communication System (RAICS) platform, for radio development at NASA Johnson Space Center. Software and hardware description language (HDL) code were delivered by NASA Glenn Research Center for use in the IPAS test bed and for development of their own Space Telecommunications Radio System (STRS) waveforms on the RAICS platform. The purpose of this document is to describe how to setup and operate the IPAS STRS Radio platform with its delivered test waveform.

Halogen occultation experiment intergrated test plan

NASA Technical Reports Server (NTRS)

Mauldin, L. E., III; Butterfield, A. J.

1986-01-01

The test program plan is presented for the Halogen Occultation Experiment (HALOE) instrument, which is being developed in-house at the Langley Research Center for the Upper Atmosphere Research Satellite (UARS). This comprehensive test program was developed to demonstrate that the HALOE instrument meets its performance requirements and maintains integrity through UARS flight environments. Each component, subsystem, and system level test is described in sufficient detail to allow development of the necessary test setups and test procedures. Additionally, the management system for implementing this test program is given. The HALOE instrument is a gas correlation radiometer that measures vertical distribution of eight upper atmospheric constituents: O3, HC1, HF, NO, CH4, H2O, NO2, and CO2.

Verifying the operational set-up of a radionuclide air-monitoring station.

PubMed

Werzi, R; Padoani, F

2007-05-01

A worldwide radionuclide network of 80 stations, part of the International Monitoring System, was designed to monitor compliance with the Comprehensive Nuclear-Test-Ban Treaty. After installation, the stations are certified to comply with the minimum requirements laid down by the Preparatory Commission of the Comprehensive Nuclear-Test-Ban Treaty Organization. Among the several certification tests carried out at each station, the verification of the radionuclide activity concentrations is a crucial one and is based on an independent testing of the airflow rate measurement system and of the gamma detector system, as well as on the assessment of the samples collected during parallel sampling and measured at radionuclide laboratories.

Verifying Data Integrity of Electronically Scanned Pressure Systems at the NASA Glenn Research Center

NASA Technical Reports Server (NTRS)

Panek, Joseph W.

2001-01-01

The proper operation of the Electronically Scanned Pressure (ESP) System critical to accomplish the following goals: acquisition of highly accurate pressure data for the development of aerospace and commercial aviation systems and continuous confirmation of data quality to avoid costly, unplanned, repeat wind tunnel or turbine testing. Standard automated setup and checkout routines are necessary to accomplish these goals. Data verification and integrity checks occur at three distinct stages, pretest pressure tubing and system checkouts, daily system validation and in-test confirmation of critical system parameters. This paper will give an overview of the existing hardware, software and methods used to validate data integrity.

Automated Transmission Loss Measurement in the Structural Acoustic Loads and Transmission Facility at NASA Langley Research Center

NASA Technical Reports Server (NTRS)

Klos, J.; Brown, S. A.

2002-01-01

A technique to measure the radiated acoustic intensity and transmission loss of panels is documented in this paper. This facility has been upgraded to include a test fixture that scans the acoustic intensity radiated from a panel on the anechoic receiving room side of the transmission loss window. The acoustic intensity incident on the panel from the reverberant side of the transmission loss window is estimated from measurements made using six stationary microphones in the reverberant source room. From the measured incident and radiated intensity, the sound power transmission loss is calculated. The setup of the facility and data acquisition system are documented. A transmission loss estimate of a typical panel is shown. The measurement-to-measurement and setup-to-setup repeatability of the transmission loss estimate are assessed. Conclusions are drawn about the ability to measure changes in transmission loss due to changes in panel construction.

Remote laboratories for optical metrology: from the lab to the cloud

NASA Astrophysics Data System (ADS)

Osten, W.; Wilke, M.; Pedrini, G.

2012-10-01

The idea of remote and virtual metrology has been reported already in 2000 with a conceptual illustration by use of comparative digital holography, aimed at the comparison of two nominally identical but physically different objects, e.g., master and sample, in industrial inspection processes. However, the concept of remote and virtual metrology can be extended far beyond this. For example, it does not only allow for the transmission of static holograms over the Internet, but also provides an opportunity to communicate with and eventually control the physical set-up of a remote metrology system. Furthermore, the metrology system can be modeled in the environment of a 3D virtual reality using CAD or similar technology, providing a more intuitive interface to the physical setup within the virtual world. An engineer or scientist who would like to access the remote real world system can log on to the virtual system, moving and manipulating the setup through an avatar and take the desired measurements. The real metrology system responds to the interaction between the avatar and the 3D virtual representation, providing a more intuitive interface to the physical setup within the virtual world. The measurement data are stored and interpreted automatically for appropriate display within the virtual world, providing the necessary feedback to the experimenter. Such a system opens up many novel opportunities in industrial inspection such as the remote master-sample-comparison and the virtual assembling of parts that are fabricated at different places. Moreover, a multitude of new techniques can be envisaged. To them belong modern ways for documenting, efficient methods for metadata storage, the possibility for remote reviewing of experimental results, the adding of real experiments to publications by providing remote access to the metadata and to the experimental setup via Internet, the presentation of complex experiments in classrooms and lecture halls, the sharing of expensive and complex infrastructure within international collaborations, the implementation of new ways for the remote test of new devices, for their maintenance and service, and many more. The paper describes the idea of remote laboratories and illustrates the potential of the approach on selected examples with special attention to optical metrology.

Verification and implementation of set-up empirical models in pile design : research project capsule.

DOT National Transportation Integrated Search

2016-08-01

The primary objectives of this research include: performing static and dynamic load tests on : newly instrumented test piles to better understand the set-up mechanism for individual soil : layers, verifying or recalibrating previously developed empir...

Implementation of an automated test setup for measuring electrical conductance of concrete.

DOT National Transportation Integrated Search

2007-01-01

This project was designed to provide the Virginia Department of Transportation (VDOT) with an automated laboratory setup for performing the rapid chloride permeability test (RCPT) to measure the electrical conductance of concrete in accordance with a...

Delft Dashboard: a quick setup tool for coastal and estuarine models

NASA Astrophysics Data System (ADS)

Nederhoff, C., III; Van Dongeren, A.; Van Ormondt, M.; Veeramony, J.

2016-02-01

We developed easy-to-use Delft DashBoard (DDB) software for the rapid set-up of coastal and estuarine hydrodynamic and basic morphological numerical models. In the "Model Maker" toolbox, users have the capability to set-up Delft3D models, in a minimal amount of time (in the order of a hour), for any location in the world. DDB draws upon public internet data sources of bathymetry and tidesto construct the model. With additional toolboxes, these models can be forced with parameterized hurricane wind fields, uplift of the sea surface due to tsunamis nested in publically available ocean models and forced with meteo data (wind speed, pressure, temperature) In this presentation we will show the skill of a model which is setup with Delft Dashboard and compare it to well-calibrated benchmark models. These latter models have been set-up using detailed input data and boundary conditions. We have tested the functionality of Delft DashBoard and evaluate the performance and robustness of the DDB model system on a variety of cases, ranging from a coastal to basin models. Furthermore, we have performed a sensitivity study to investigate the most critical physical and numerical processes. The software can benefit operational modellers, as well as scientists and consultants.

Quantum contextuality in N-boson systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Benatti, Fabio; Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, I-34014 Trieste; Floreanini, Roberto

2011-09-15

Quantum contextuality in systems of identical bosonic particles is explicitly exhibited via the maximum violation of a suitable inequality of Clauser-Horne-Shimony-Holt type. Unlike the approaches considered so far, which make use of single-particle observables, our analysis involves collective observables constructed using multiboson operators. An exemplifying scheme to test this violation with a quantum optical setup is also discussed.

Nonlinear imaging (NIM) of barely visible impact damage (BVID) in composite panels using a semi and full air-coupled linear and nonlinear ultrasound technique

NASA Astrophysics Data System (ADS)

Malfense Fierro, Gian Piero; Meo, Michele

2018-03-01

Two non-contact methods were evaluated to address the reliability and reproducibility concerns affecting industry adoption of nonlinear ultrasound techniques for non-destructive testing and evaluation (NDT/E) purposes. A semi and a fully air-coupled linear and nonlinear ultrasound method was evaluated by testing for barely visible impact damage (BVID) in composite materials. Air coupled systems provide various advantages over contact driven systems; such as: ease of inspection, no contact and lubrication issues and a great potential for non-uniform geometry evaluation. The semi air-coupled setup used a suction attached piezoelectric transducer to excite the sample and an array of low-cost microphones to capture the signal over the inspection area, while the second method focused on a purely air-coupled setup, using an air-coupled transducer to excite the structure and capture the signal. One of the issues facing nonlinear and any air-coupled systems is transferring enough energy to stimulate wave propagation and in the case of nonlinear ultrasound; damage regions. Results for both methods provided nonlinear imaging (NIM) of damage regions using a sweep excitation methodology, with the semi aircoupled system providing clearer results.

Alternatives to Pyrotechnic Distress Signals; Laboratory and Field Studies

DTIC Science & Technology

2015-03-01

using night vision imaging systems (NVIS) with “minus-blue” filtering,” the project recommends additional research and testing leading to the inclusion...18  5.2.3  Background Images ...Example of image capture from radiant imaging colorimeter. ....................................................... 16  Figure 10. Laboratory setup

Assessment of the Tensile Properties for Single Fibers

DTIC Science & Technology

2018-02-01

Approved for public release; distribution is unlimited. 14. ABSTRACT A novel experimental test method is presented to assess the tensile properties...distribution is unlimited. iii Contents List of Figures iv List of Tables v Acknowledgments vi 1. Introduction 1 2. Experimental Procedure 2 2.1 Test...fiber diameter measurements .............................. 7 Fig. 5 The coordinate system defining the experimental setup with the x- direction along

Combined UHV/high-pressure catalysis setup for depth-resolved near-surface spectroscopic characterization and catalytic testing of model catalysts

NASA Astrophysics Data System (ADS)

Mayr, Lukas; Rameshan, Raffael; Klötzer, Bernhard; Penner, Simon; Rameshan, Christoph

2014-05-01

An ultra-high vacuum (UHV) setup for "real" and "inverse" model catalyst preparation, depth-resolved near-surface spectroscopic characterization, and quantification of catalytic activity and selectivity under technologically relevant conditions is described. Due to the all-quartz reactor attached directly to the UHV-chamber, transfer of the catalyst for in situ testing without intermediate contact to the ambient is possible. The design of the UHV-compatible re-circulating batch reactor setup allows the study of reaction kinetics under close to technically relevant catalytic conditions up to 1273 K without contact to metallic surfaces except those of the catalyst itself. With the attached differentially pumped exchangeable evaporators and the quartz-microbalance thickness monitoring equipment, a reproducible, versatile, and standardised sample preparation is possible. For three-dimensional near-surface sample characterization, the system is equipped with a hemispherical analyser for X-ray photoelectron spectroscopy (XPS), electron-beam or X-ray-excited Auger-electron spectroscopy, and low-energy ion scattering measurements. Due the dedicated geometry of the X-ray gun (54.7°, "magic angle") and the rotatable sample holder, depth analysis by angle-resolved XPS measurements can be performed. Thus, by the combination of characterisation methods with different information depths, a detailed three-dimensional picture of the electronic and geometric structure of the model catalyst can be obtained. To demonstrate the capability of the described system, comparative results for depth-resolved sample characterization and catalytic testing in methanol steam reforming on PdGa and PdZn near-surface intermetallic phases are shown.

Analysis of Photogrammetry Data from ISIM Mockup

NASA Technical Reports Server (NTRS)

Nowak, Maria; Hill, Mike

2007-01-01

During ground testing of the Integrated Science Instrument Module (ISIM) for the James Webb Space Telescope (JWST), the ISIM Optics group plans to use a Photogrammetry Measurement System for cryogenic calibration of specific target points on the ISIM composite structure and Science Instrument optical benches and other GSE equipment. This testing will occur in the Space Environmental Systems (SES) chamber at Goddard Space Flight Center. Close range photogrammetry is a 3 dimensional metrology system using triangulation to locate custom targets in 3 coordinates via a collection of digital photographs taken from various locations and orientations. These photos are connected using coded targets, special targets that are recognized by the software and can thus correlate the images to provide a 3 dimensional map of the targets, and scaled via well calibrated scale bars. Photogrammetry solves for the camera location and coordinates of the targets simultaneously through the bundling procedure contained in the V-STARS software, proprietary software owned by Geodetic Systems Inc. The primary objectives of the metrology performed on the ISIM mock-up were (1) to quantify the accuracy of the INCA3 photogrammetry camera on a representative full scale version of the ISIM structure at ambient temperature by comparing the measurements obtained with this camera to measurements using the Leica laser tracker system and (2), empirically determine the smallest increment of target position movement that can be resolved by the PG camera in the test setup, i.e., precision, or resolution. In addition, the geometrical details of the test setup defined during the mockup testing, such as target locations and camera positions, will contribute to the final design of the photogrammetry system to be used on the ISIM Flight Structure.

Setup of a photomultiplier tube test bench for LHAASO-KM2A

NASA Astrophysics Data System (ADS)

Wang, Xu; Zhang, Zhong-Quan; Tian, Ye; Du, Yan-Yan; Zhao, Xiao; Shen, Fu-Wang; Li, Chang-Yu; Sun, Yan-Sheng; Feng, Cun-Feng

2016-08-01

To fulfill the requirements for testing the photomultiplier tubes (PMTs) of the electromagnetic detector at the Large High Altitude Air Shower Observatory (LHAASO), a multi-functional PMT test bench with a two-dimensional scanning system has been developed. With this 2D scanning system, 16 PMTs can be scanned simultaneously for characteristics tests, including uniformity, cathode transit time difference, single photo-electron spectrum, gain vs. high voltage, linear behavior and dark noise. The programmable hardware and intelligent software of the test bench make it convenient to use and provide reliable results. The test methods are described in detail and primary results are presented. Supported by NSFC (11075096) SDNFS (ZR2011AM007), China

Multiple transfer standard for calibration and characterization of test setups for LED lamps and luminaires in industry

NASA Astrophysics Data System (ADS)

Sperling, A.; Meyer, M.; Pendsa, S.; Jordan, W.; Revtova, E.; Poikonen, T.; Renoux, D.; Blattner, P.

2018-04-01

Proper characterization of test setups used in industry for testing and traceable measurement of lighting devices by the substitution method is an important task. According to new standards for testing LED lamps, luminaires and modules, uncertainty budgets are requested because in many cases the properties of the device under test differ from the transfer standard used, which may cause significant errors, for example if a LED-based lamp is tested or calibrated in an integrating sphere which was calibrated with a tungsten lamp. This paper introduces a multiple transfer standard, which was designed not only to transfer a single calibration value (e.g. luminous flux) but also to characterize test setups used for LED measurements with additional provided and calibrated output features to enable the application of the new standards.

The Advanced Communication Technology Satellite and ISDN

NASA Technical Reports Server (NTRS)

Lowry, Peter A.

1996-01-01

This paper depicts the Advanced Communication Technology Satellite (ACTS) system as a global central office switch. The ground portion of the system is the collection of earth stations or T1-VSAT's (T1 very small aperture terminals). The control software for the T1-VSAT's resides in a single CPU. The software consists of two modules, the modem manager and the call manager. The modem manager (MM) controls the RF modem portion of the T1-VSAT. It processes the orderwires from the satellite or from signaling generated by the call manager (CM). The CM controls the Recom Laboratories MSPs by receiving signaling messages from the stacked MSP shelves ro units and sending appropriate setup commands to them. There are two methods used to setup and process calls in the CM; first by dialing up a circuit using a standard telephone handset or, secondly by using an external processor connected to the CPU's second COM port, by sending and receiving signaling orderwires. It is the use of the external processor which permits the ISDN (Integrated Services Digital Network) Signaling Processor to implement ISDN calls. In August 1993, the initial testing of the ISDN Signaling Processor was carried out at ACTS System Test at Lockheed Marietta, Princeton, NJ using the spacecraft in its test configuration on the ground.

Analysis of dispatching rules in a stochastic dynamic job shop manufacturing system with sequence-dependent setup times

NASA Astrophysics Data System (ADS)

Sharma, Pankaj; Jain, Ajai

2014-12-01

Stochastic dynamic job shop scheduling problem with consideration of sequence-dependent setup times are among the most difficult classes of scheduling problems. This paper assesses the performance of nine dispatching rules in such shop from makespan, mean flow time, maximum flow time, mean tardiness, maximum tardiness, number of tardy jobs, total setups and mean setup time performance measures viewpoint. A discrete event simulation model of a stochastic dynamic job shop manufacturing system is developed for investigation purpose. Nine dispatching rules identified from literature are incorporated in the simulation model. The simulation experiments are conducted under due date tightness factor of 3, shop utilization percentage of 90% and setup times less than processing times. Results indicate that shortest setup time (SIMSET) rule provides the best performance for mean flow time and number of tardy jobs measures. The job with similar setup and modified earliest due date (JMEDD) rule provides the best performance for makespan, maximum flow time, mean tardiness, maximum tardiness, total setups and mean setup time measures.

Microservices for systematic profiling and monitoring of the refactoring process at the LHCb experiment

NASA Astrophysics Data System (ADS)

Mazurov, Alexander; Couturier, Ben; Popov, Dmitry; Farley, Nathanael

2017-10-01

Any time you modify an implementation within a program, change compiler version or operating system, you should also do regression testing. You can do regression testing by rerunning existing tests against the changes to determine whether this breaks anything that worked prior to the change and by writing new tests where necessary. At LHCb we have a huge codebase which is maintained by many people and can be run within different setups. Such situations lead to the crucial necessity to guide refactoring with a central profiling system that helps to run tests and find the impact of changes. In our work we present a software architecture and tools for running a profiling system. This system is responsible for systematically running regression tests, collecting and comparing results of these tests so changes between different setups can be observed and reported. The main feature of our solution is that it is based on a microservices architecture. Microservices break a large project into loosely coupled modules, which communicate with each other through simple APIs. Such modular architectural style helps us to avoid general pitfalls of monolithic architectures such as hard to understand a codebase as well as maintaining a large codebase and ineffective scalability. Our solution also allows to escape a complexity of microservices deployment process by using software containers and services management tools. Containers and service managers let us quickly deploy linked modules in development, production or in any other environments. Most of the developed modules are generic which means that the proposed architecture and tools can be used not only in LHCb but adopted for other experiments and companies.

Very high stability systems: LMJ target alignment system and MTG imager test setup

NASA Astrophysics Data System (ADS)

Compain, Eric; Maquet, Philippe; Kunc, Thierry; Marque, Julien; Lauer-Solelhac, Maxime; Delage, Laurent; Lanternier, Catherine

2015-09-01

Most of space instruments and research facilities require test equipment with demanding opto-mechanical stability. In some specific cases, when the stability performance directly drives the final performance of the scientific mission and when feasibility is questionable, specific methods must be implemented for the associated technical risk management. In present paper, we will present our heritage in terms of methodology, design, test and the associated results for two specific systems : the SOPAC-POS and the MOTA, generating new references for future developments. From a performance point of view, we will emphasis on following key parameters : design symmetry, thermal load management, and material and structural choices. From a method point of view the difficulties arise first during design, from the strong coupling between the thermal, mechanical and optical performance models, and then during testing, from the difficulty of conceiving test setup having appropriate performance level. We will present how these limitations have been overcome. SOPAC-POS is the target alignment system of the LMJ, Laser Mega Joule, the French inertial confinement fusion research center. Its stability has been demonstrated by tests in 2014 after 10 years of research and development activities, achieving 1μm stability @ 6m during one hour periods. MOTA is an Optical Ground Support Equipment aiming at qualifying by tests the Flexible Combined Imager (FCI). FCI is an instrument for the meteorological satellite MTG-I, a program of and funded by the European Space Agency and under prime contractorship of Thales Alenia Space. Optimized design will allow to get better than 0.2 μrad stability for one hour periods, as required for MTF measurement.

Mass Property Measurements of the Mars Science Laboratory Rover

NASA Technical Reports Server (NTRS)

Fields, Keith

2012-01-01

The NASA/JPL Mars Science Laboratory (MSL) spacecraft mass properties were measured on a spin balance table prior to launch. This paper discusses the requirements and issues encountered with the setup, qualification, and testing using the spin balance table, and the idiosyncrasies encountered with the test system. The final mass measurements were made in the Payload Hazardous Servicing Facility (PHSF) at Kennedy Space Center on the fully assembled and fueled spacecraft. This set of environmental tests required that the control system for the spin balance machine be at a remote location, which posed additional challenges to the operation of the machine

Scientific Research Program for Power, Energy, and Thermal Technologies. Task Order 0002: Power, Thermal and Control Technologies and Processes Experimental Research. Subtask: Laboratory Test Set-up to Evaluate Electromechanical Actuation Systems for Aircraft Flight Control

DTIC Science & Technology

2015-08-01

faults are incorporated into the system in order to better understand the EMA reliability, and to aid in designing fault detection software for real...to a fixed angle repeatedly and accurately [16]. The motor in the EHA is used to drive a reversible pump tied to a hydraulic cylinder which moves...24] [25] [26]. These test stands are used for the prognostic testing of EMAS that have had mechanical or electrical faults injected into them. The

Design techniques for developing a computerized instrumentation test plan. [for wind tunnel test data acquisition system

NASA Technical Reports Server (NTRS)

Burnett, S. Kay; Forsyth, Theodore J.; Maynard, Everett E.

1987-01-01

The development of a computerized instrumentation test plan (ITP) for the NASA/Ames Research Center National Full Scale Aerodynamics Complex (NFAC) is discussed. The objective of the ITP program was to aid the instrumentation engineer in documenting the configuration and calibration of data acquisition systems for a given test at any of four low speed wind tunnel facilities (Outdoor Aerodynamic Research Facility, 7 x 10, 40 x 80, and 80 x 120) at the NFAC. It is noted that automation of the ITP has decreased errors, engineering hours, and setup time while adding a higher level of consistency and traceability.

A prototype gas exchange monitor for exercise stress testing aboard NASA Space Station

NASA Technical Reports Server (NTRS)

Orr, Joseph A.; Westenskow, Dwayne R.; Bauer, Anne

1989-01-01

This paper describes an easy-to-use monitor developed to track the weightlessness deconditioning aboard the NASA Space Station, together with the results of testing of a prototype instrument. The monitor measures the O2 uptake and CO2 production, and calculates the maximum O2 uptake and anaerobic threshold during an exercise stress test. The system uses two flowmeters in series to achieve a completely automatic calibration, and uses breath-by-breath compensation for sample line-transport delay. The monitor was evaluated using two laboratory methods and was shown to be accurate. The system's block diagram and the bench test setup diagram are included.

Test Setup For Model Landing Investigation of a Winged Space Vehicle

NASA Image and Video Library

1960-07-20

Test Setup For Model Landing Investigation of a Winged Space Vehicle Image used in NASA Document TN-D-1496 1960-L-04633.01 is Figure 9a for NASA Document L-2064 Photograph of model on launcher and landing on runway.

Velocity Plume Profiles for Hall Thrusters Using Laser Diagnostic

DTIC Science & Technology

2010-06-01

53 Collecting LIF Using Fiber Optics .............................................................................58 Vacuum ...54 Figure 40. Etalon Issue Through Vacuum Chamber Window [25]. ................................. 55 Figure 41. Collimator with Adapter in a...Methodology Facility Set-up Vacuum Chamber Testing took place within a vacuum chamber located at the AFIT Space Propulsion Analysis and System Simulation

Design, analysis, and test verification of advanced encapsulation systems

NASA Technical Reports Server (NTRS)

Mardesich, N.; Minning, C.

1982-01-01

Design sensitivities are established for the development of photovoltaic module criteria and the definition of needed research tasks. The program consists of three phases. In Phase I, analytical models were developed to perform optical, thermal, electrical, and structural analyses on candidate encapsulation systems. From these analyses several candidate systems will be selected for qualification testing during Phase II. Additionally, during Phase II, test specimens of various types will be constructed and tested to determine the validity of the analysis methodology developed in Phase I. In Phse III, a finalized optimum design based on knowledge gained in Phase I and II will be developed. All verification testing was completed during this period. Preliminary results and observations are discussed. Descriptions of the thermal, thermal structural, and structural deflection test setups are included.

Measurement of the UH-60A Hub Large Rotor Test Apparatus Control System Stiffness

NASA Technical Reports Server (NTRS)

Kufeld, Robert M.

2014-01-01

This purpose of this report is to provides details of the measurement of the control system stiffness of the UH-60A rotor hub mounted on the Large Rotor Test Apparatus (UH-60A/LRTA). The UH-60A/LRTA was used in the 40- by 80-Foot Wind Tunnel to complete the full-scale wind tunnel test portion of the NASA / ARMY UH-60A Airloads Program. This report describes the LRTA control system and highlights the differences between the LRTA and UH-60A aircraft. The test hardware, test setup, and test procedures are also described. Sample results are shown, including the azimuthal variation of the measured control system stiffness for three different loadings and two different dynamic actuator settings. Finally, the azimuthal stiffness is converted to fixed system values using multi-blade transformations for input to comprehensive rotorcraft prediction codes.

TPS In-Flight Health Monitoring Project Progress Report

NASA Technical Reports Server (NTRS)

Kostyk, Chris; Richards, Lance; Hudston, Larry; Prosser, William

2007-01-01

Progress in the development of new thermal protection systems (TPS) is reported. New approaches use embedded lightweight, sensitive, fiber optic strain and temperature sensors within the TPS. Goals of the program are to develop and demonstrate a prototype TPS health monitoring system, develop a thermal-based damage detection algorithm, characterize limits of sensor/system performance, and develop ea methodology transferable to new designs of TPS health monitoring systems. Tasks completed during the project helped establish confidence in understanding of both test setup and the model and validated system/sensor performance in a simple TPS structure. Other progress included complete initial system testing, commencement of the algorithm development effort, generation of a damaged thermal response characteristics database, initial development of a test plan for integration testing of proven FBG sensors in simple TPS structure, and development of partnerships to apply the technology.

Laboratory measurements of on-board subsystems

NASA Technical Reports Server (NTRS)

Nuspl, P. P.; Dong, G.; Seran, H. C.

1991-01-01

Good progress was achieved on the test bed for on-board subsystems for future satellites. The test bed is for subsystems developed previously. Four test setups were configured in the INTELSAT technical labs: (1) TDMA on-board modem; (2) multicarrier demultiplexer demodulator; (3) IBS/IDR baseband processor; and (4) baseband switch matrix. The first three series of tests are completed and the tests on the BSM are in progress. Descriptions of test setups and major test results are included; the format of the presentation is outlined.

Research on mechanical and sensoric set-up for high strain rate testing of high performance fibers

NASA Astrophysics Data System (ADS)

Unger, R.; Schegner, P.; Nocke, A.; Cherif, C.

2017-10-01

Within this research project, the tensile behavior of high performance fibers, such as carbon fibers, is investigated under high velocity loads. This contribution (paper) focuses on the clamp set-up of two testing machines. Based on a kinematic model, weight optimized clamps are designed and evaluated. By analyzing the complex dynamic behavior of conventional high velocity testing machines, it has been shown that the impact typically exhibits an elastic characteristic. This leads to barely predictable breaking speeds and will not work at higher speeds when acceleration force exceeds material specifications. Therefore, a plastic impact behavior has to be achieved, even at lower testing speeds. This type of impact behavior at lower speeds can be realized by means of some minor test set-up adaptions.

Experimental setup for precise measurement of losses in high-temperature superconducting transformer

NASA Astrophysics Data System (ADS)

Janu, Z.; Wild, J.; Repa, P.; Jelinek, Z.; Zizek, F.; Peksa, L.; Soukup, F.; Tichy, R.

2006-10-01

A simple cryogenic system for testing of the superconducting power transformer was constructed. Thermal shielding is provided by additional liquid nitrogen bath instead of super-insulation. The system, together with use of a precise nitrogen liquid level meter, permitted calorimetric measurements of losses of the 8 kVA HTS transformer with a resolution of the order of 0.1 W.

Rock samples analysis with the pyrolysis system of the Mars Organic Molecule Analyzer (MOMA)

NASA Astrophysics Data System (ADS)

Steininger, H.; Goetz, W.; Goesmann, F.

2012-12-01

The Mars Organic Molecule Analyzer (MOMA) is a combined pyrolysis gas chromatograph mass spectrometer (GC-MS) and laser desorption mass spectrometer (LD-MS). It will be the key instrument of the ESA/Roscosmos ExoMars 2018 mission to search for extinct and extant life. Additionally the instrument will be able to detect the organic background which has possibly been delivered to Mars by meteorites. Several samples containing a wide range of organic molecules have been tested with a flight analog injection system. The results of the tests were compared to results obtained by a commercial pyrolysis system, the Pyrola pyrolysis unit. The first experimental setup (Pyrola unit) consists of a small quartz tube with an electrically heated platinum filament. A constant helium flow transports the volatilized compounds through an injection needle directly into the injector of the GC. The whole system is heated to 175°C. The second experimental setup (flight analog injection system) consists of a 6 mm diameter platinum oven connected to a microvalve plate to route the gas from the oven to the GC. The microvalves can be switched electrically. The volatiles are subsequently trapped in a cold trap consisting of a Tenax filed tube. Heating this tube releases the volatiles and injects them through an injection needle into the GC. A Varian 4000 GC-MS with RTX-5 column was used to separate and analyze the volatiles generated from both experimental setups. During the experiments several natural rock samples with a broad content of organic material have been analyzed. The sample material was crushed and ground. To obtain comparable results the same amount of sample was used in both setups. Lower temperatures were used in the flight analog injection system due to restrictions of the reusable oven. Lower temperatures normally lead to only a slight decrease in the very heavy and non-volatile compounds but do not change the overall appearance of the chromatogram. Significant differences in the amount and composition of organic compounds have been found in the GC traces. In the flight like configuration an increase of the light volatile compounds was observed especially for benzene and toluene. We want to acknowledge the support by DLR (FKZ 50QX1001).

Methodical aspects of text testing in a driving simulator.

PubMed

Sundin, A; Patten, C J D; Bergmark, M; Hedberg, A; Iraeus, I-M; Pettersson, I

2012-01-01

A test with 30 test persons was conducted in a driving simulator. The test was a concept exploration and comparison of existing user interaction technologies for text message handling with focus on traffic safety and experience (technology familiarity and learning effects). Focus was put on methodical aspects how to measure and how to analyze the data. Results show difficulties with the eye tracking system (calibration etc.) per se, and also include the subsequent raw data preparation. The physical setup in the car where found important for the test completion.

Development and implementation of a portable grating interferometer system as a standard tool for testing optics at the Advanced Photon Source beamline 1-BM

DOE Office of Scientific and Technical Information (OSTI.GOV)

Assoufid, Lahsen; Shi, Xianbo; Marathe, Shashidhara

We developed a portable X-ray grating interferometer setup as a standard tool for testing optics at the Advanced Photon Source (APS) beamline 1-BM. The interferometer can be operated in phase-stepping, Moiré, or single-grating harmonic imaging mode with 1-D or 2-D gratings. All of the interferometer motions are motorized; hence, it is much easier and quicker to switch between the different modes of operation. A novel aspect of this new instrument is its designed portability. While the setup is designed to be primarily used as a standard tool for testing optics at 1-BM, it could be potentially deployed at other APSmore » beamlines for beam coherence and wavefront characterization or imaging. The design of the interferometer system is described in detail and coherence measurements obtained at the APS 34-ID-E beamline are presented. The coherence was probed in two directions using a 2-D checkerboard, a linear, and a circular grating at X-ray energies of 8 keV, 11 keV, and 18 keV.« less

Large Field Photogrammetry Techniques in Aircraft and Spacecraft Impact Testing

NASA Technical Reports Server (NTRS)

Littell, Justin D.

2010-01-01

The Landing and Impact Research Facility (LandIR) at NASA Langley Research Center is a 240 ft. high A-frame structure which is used for full-scale crash testing of aircraft and rotorcraft vehicles. Because the LandIR provides a unique capability to introduce impact velocities in the forward and vertical directions, it is also serving as the facility for landing tests on full-scale and sub-scale Orion spacecraft mass simulators. Recently, a three-dimensional photogrammetry system was acquired to assist with the gathering of vehicle flight data before, throughout and after the impact. This data provides the basis for the post-test analysis and data reduction. Experimental setups for pendulum swing tests on vehicles having both forward and vertical velocities can extend to 50 x 50 x 50 foot cubes, while weather, vehicle geometry, and other constraints make each experimental setup unique to each test. This paper will discuss the specific calibration techniques for large fields of views, camera and lens selection, data processing, as well as best practice techniques learned from using the large field of view photogrammetry on a multitude of crash and landing test scenarios unique to the LandIR.

Explosive component acceptance tester using laser interferometer technology

NASA Technical Reports Server (NTRS)

Wickstrom, Richard D.; Tarbell, William W.

1993-01-01

Acceptance testing of explosive components requires a reliable and simple to use testing method that can discern less than optimal performance. For hot-wire detonators, traditional techniques use dent blocks or photographic diagnostic methods. More complicated approaches are avoided because of their inherent problems with setup and maintenance. A recently developed tester is based on using a laser interferometer to measure the velocity of flying plates accelerated by explosively actuated detonators. Unlike ordinary interferometers that monitor displacement of the test article, this device measures velocity directly and is commonly used with non-spectral surfaces. Most often referred to as the VISAR technique (Velocity Interferometer System for Any Reflecting Surface), it has become the most widely-accepted choice for accurate measurement of velocity in the range greater than 1 mm/micro-s. Traditional VISAR devices require extensive setup and adjustment and therefore are unacceptable in a production-testing environment. This paper describes a new VISAR approach which requires virtually no adjustments, yet provides data with accuracy comparable to the more complicated systems. The device, termed the Fixed-Cavity VISAR, is currently being developed to serve as a product verification tool for hot-wire detonators and slappers. An extensive data acquisition and analysis computer code was also created to automate the manipulation of raw data into final results.

Mechanical characterization of a short fiber-reinforced polymer at room temperature: experimental setups evaluated by an optical measurement system

NASA Astrophysics Data System (ADS)

Röhrig, C.; Scheffer, T.; Diebels, S.

2017-09-01

Composite materials are of great interest for industrial applications because of their outstanding properties. Each composite material has its own characteristics due to the large number of possible combinations of matrix and filler. As a result of their compounding, composites usually show a complex material behavior. This work is focused on the experimental testing of a short fiber-reinforced thermoplastic composite at room temperature. The characteristic behavior of this material class is often based on a superposition of typical material effects. The predicted characteristic material properties such as elasto-plasticity, damage and anisotropy of the investigated material are obtained from results of cyclic uniaxial tensile tests at constant strain rate. Concerning the manufacturing process as well as industrial applications, the experimental investigations are extended to multiaxial loading situations. Therefore, the composite material is examined with a setup close to a deep-drawing process, the Nakajima test (Nakazima et al. in Study on the formability of steel sheets. Yawate Technical Report No. 264, pp 8517-8530, 1968). The evaluation of the experimental investigations is provided by an optical analysis system using a digital image correlation software. Finally, based on the results of the uniaxial tensile tests, a one-dimensional macroscopic model is introduced and first results of the simulation are provided.

Combustion of LOX with H2(sub g) under subcritical, critical, and supercritical conditions (Task 1) and experimental observation of dense spray and mixing of impinging jets (Task 2)

NASA Technical Reports Server (NTRS)

Kuo, K. K.; Hsieh, W. H.; Cheung, F. B.; Yang, A. S.; Brown, J. J.; Woodward, R. D.; Kline, M. C.; Burch, R. L.

1992-01-01

The objective was to achieve a better understanding of the combustion processes of liquid oxygen and gaseous hydrogen under broad range of pressure covering subcritical, critical, and supercritical conditions. The scope of the experimental work falls into the following areas: (1) design of the overall experimental setup; (2) modification of an existing windowed high pressure chamber; (3) design of the LOX feeding system; (4) provision of the safety features in the test rig design; (5) LOX cleanliness requirements; (6) cold shock testing; (7) implementation of data acquisition systems; (8) preliminary tests for system checkout; (9) modification of LOX feeding system; and (10) evaporation tests. Progress in each area is discussed.

Field instrumentation and testing to study set-up phenomenon of piles driven into Louisiana clayey soils : final report.

DOT National Transportation Integrated Search

2016-07-01

This research study aims to investigate the pile set-up phenomenon for clayey soils and develop empirical models to predict pile set-up : resistance at certain time after end of driving (EOD). To fulfill the objective, a total number of twelve prestr...

SU-E-T-261: Development of An Automated System to Detect Patient Identification and Positioning Errors Prior to Radiotherapy Treatment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jani, S; Low, D; Lamb, J

2015-06-15

Purpose: To develop a system that can automatically detect patient identification and positioning errors using 3D computed tomography (CT) setup images and kilovoltage CT (kVCT) planning images. Methods: Planning kVCT images were collected for head-and-neck (H&N), pelvis, and spine treatments with corresponding 3D cone-beam CT (CBCT) and megavoltage CT (MVCT) setup images from TrueBeam and TomoTherapy units, respectively. Patient identification errors were simulated by registering setup and planning images from different patients. Positioning errors were simulated by misaligning the setup image by 1cm to 5cm in the six anatomical directions for H&N and pelvis patients. Misalignments for spine treatments weremore » simulated by registering the setup image to adjacent vertebral bodies on the planning kVCT. A body contour of the setup image was used as an initial mask for image comparison. Images were pre-processed by image filtering and air voxel thresholding, and image pairs were assessed using commonly-used image similarity metrics as well as custom -designed metrics. A linear discriminant analysis classifier was trained and tested on the datasets, and misclassification error (MCE), sensitivity, and specificity estimates were generated using 10-fold cross validation. Results: Our workflow produced MCE estimates of 0.7%, 1.7%, and 0% for H&N, pelvis, and spine TomoTherapy images, respectively. Sensitivities and specificities ranged from 98.0% to 100%. MCEs of 3.5%, 2.3%, and 2.1% were obtained for TrueBeam images of the above sites, respectively, with sensitivity and specificity estimates between 96.2% and 98.4%. MCEs for 1cm H&N/pelvis misalignments were 1.3/5.1% and 9.1/8.6% for TomoTherapy and TrueBeam images, respectively. 2cm MCE estimates were 0.4%/1.6% and 3.1/3.2%, respectively. Vertebral misalignment MCEs were 4.8% and 4.9% for TomoTherapy and TrueBeam images, respectively. Conclusion: Patient identification and gross misalignment errors can be robustly and automatically detected using 3D setup images of two imaging modalities across three commonly-treated anatomical sites.« less

Field instrumentation and testing to study set-up phenomenon of piles driven into Louisiana clayey soils.

DOT National Transportation Integrated Search

2011-02-01

The main objective of this research study is to evaluate the time-dependent increase in pile capacity (or pile setup phenomenon) for piles driven into Louisiana soils through conducting repeated static and dynamic field testing with time on full-scal...

Positron lifetime setup based on DRS4 evaluation board

NASA Astrophysics Data System (ADS)

Petriska, M.; Sojak, S.; Slugeň, V.

2014-04-01

A digital positron lifetime setup based on DRS4 evaluation board designed at the Paul Scherrer Institute has been constructed and tested in the Positron annihilation laboratory Slovak University of Technology Bratislava. The high bandwidth, low power consumption and short readout time make DRS4 chip attractive for positron annihilation lifetime (PALS) setup, replacing traditional ADCs and TDCs. A software for PALS setup online and offline pulse analysis was developed with Qt,Qwt and ALGLIB libraries.

Electrical Evaluation of RCA MWS5001D Random Access Memory, Volume 5, Appendix D

NASA Technical Reports Server (NTRS)

Klute, A.

1979-01-01

The electrical characterization and qualification test results are presented for the RCA MWS 5001D random access memory. The tests included functional tests, AC and DC parametric tests, AC parametric worst-case pattern selection test, determination of worst-case transition for setup and hold times, and a series of schmoo plots. Average input high current, worst case input high current, output low current, and data setup time are some of the results presented.

Electrical Evaluation of RCA MWS5501D Random Access Memory, Volume 2, Appendix a

NASA Technical Reports Server (NTRS)

Klute, A.

1979-01-01

The electrical characterization and qualification test results are presented for the RCA MWS5001D random access memory. The tests included functional tests, AC and DC parametric tests, AC parametric worst-case pattern selection test, determination of worst-case transition for setup and hold times, and a series of schmoo plots. The address access time, address readout time, the data hold time, and the data setup time are some of the results surveyed.

Adhesive Bonding for Optical Metrology Systems in Space Applications

NASA Astrophysics Data System (ADS)

Gohlke, Martin; Schuldt, Thilo; Döringshoff, Klaus; Peters, Achim; Johann, Ulrich; Weise, Dennis; Braxmaier, Claus

2015-05-01

Laser based metrology systems become more and more attractive for space applications and are the core elements of planned missions such as LISA (NGO, eLISA) or NGGM where laser interferometry is used for distance measurements between satellites. The GRACE-FO mission will for the first time demonstrate a Laser Ranging Instrument (LRI) in space, starting 2017. Laser based metrology also includes optical clocks/references, either as ultra-stable light source for high sensitivity interferometry or as scientific payload e.g. proposed in fundamental physics missions such as mSTAR (mini SpaceTime Asymmetry Research), a mission dedicated to perform a Kennedy-Thorndike experiment on a satellite in a low-Earth orbit. To enable the use of existing optical laboratory setups, optimization with respect to power consumption, weight and dimensions is necessary. At the same time the thermal and structural stability must be increased. Over the last few years we investigated adhesive bonding of optical components to thermally highly stable glass ceramics as an easy-to-handle assembly integration technology. Several setups were implemented and tested for potential later use in space applications. We realized a heterodyne LISA related interferometer with demonstrated noise levels in the pm-range for translation measurement and nano-radiant-range for tilt measurements and two iodine frequency references on Elegant Breadboard (EBB) and Engineering Model (EM) level with frequency stabilities in the 10-15 range for longer integration times. The EM setup was thermally cycled and vibration tested.

Study of Parameters Affecting the Level of Ultrasound Exposure with In Vitro Set-Ups

NASA Astrophysics Data System (ADS)

Leskinen, Jarkko J.; Hynynen, Kullervo

2010-03-01

Ultrasound (US) exposures are widely used with in vitro cell systems e.g. in stem cell and tissue engineering research. However, without the knowledge of factors affecting the level of US exposure, the outcome of the biological result may vary from test to test or even be misinterpreted. Thereby, some of the factors affecting in vitro US exposures were studied. The level of US exposure was characterized in standard commercial cell culturing plates. The temperature distributions were measured inside the wells using infrared camera and fine wire thermocouples, and pressure and intensity distributions using a laser vibrometer and a schlieren system. The measurements were made at operating frequency of around 1 MHz with varying temporal parameters and powers (up to 2 W of acoustic power). Heat accumulation between the wells varied up to 40-50% depending on the location of the well on the plate. This well-to-well variation was be linked to the activity of reporter plasmid on osteoblastic cells. Similar temperature variations within the wells were also measured. Small sub-wavelength change in the exposure distance or, respectively, liquid volume inside the well was found to alter the acoustic field in both magnitude and shape due the standing waves. The gathered data reveals the complexity of the acoustic field in a typical in vitro set-up and gives new information about the environment of the in vitro cells during US exposures. This data may be especially useful when US set-ups are designed or characterized.

Development of a grinding-specific performance test set-up.

PubMed

Olesen, C G; Larsen, B H; Andresen, E L; de Zee, M

2015-01-01

The aim of this study was to develop a performance test set-up for America's Cup grinders. The test set-up had to mimic the on-boat grinding activity and be capable of collecting data for analysis and evaluation of grinding performance. This study included a literature-based analysis of grinding demands and a test protocol developed to accommodate the necessary physiological loads. This study resulted in a test protocol consisting of 10 intervals of 20 revolutions each interspersed with active resting periods of 50 s. The 20 revolutions are a combination of both forward and backward grinding and an exponentially rising resistance. A custom-made grinding ergometer was developed with computer-controlled resistance and capable of collecting data during the test. The data collected can be used to find measures of grinding performance such as peak power, time to complete and the decline in repeated grinding performance.

A routine quality assurance test for CT automatic exposure control systems.

PubMed

Iball, Gareth R; Moore, Alexis C; Crawford, Elizabeth J

2016-07-08

The study purpose was to develop and validate a quality assurance test for CT automatic exposure control (AEC) systems based on a set of nested polymethylmethacrylate CTDI phantoms. The test phantom was created by offsetting the 16 cm head phantom within the 32 cm body annulus, thus creating a three part phantom. This was scanned at all acceptance, routine, and some nonroutine quality assurance visits over a period of 45 months, resulting in 115 separate AEC tests on scanners from four manufacturers. For each scan the longitudinal mA modulation pattern was generated and measurements of image noise were made in two annular regions of interest. The scanner displayed CTDIvol and DLP were also recorded. The impact of a range of AEC configurations on dose and image quality were assessed at acceptance testing. For systems that were tested more than once, the percentage of CTDIvol values exceeding 5%, 10%, and 15% deviation from baseline was 23.4%, 12.6%, and 8.1% respectively. Similarly, for the image noise data, deviations greater than 2%, 5%, and 10% from baseline were 26.5%, 5.9%, and 2%, respectively. The majority of CTDIvol and noise deviations greater than 15% and 5%, respectively, could be explained by incorrect phantom setup or protocol selection. Barring these results, CTDIvol deviations of greater than 15% from baseline were found in 0.9% of tests and noise deviations greater than 5% from baseline were found in 1% of tests. The phantom was shown to be sensitive to changes in AEC setup, including the use of 3D, longitudinal or rotational tube current modulation. This test methodology allows for continuing performance assessment of CT AEC systems, and we recommend that this test should become part of routine CT quality assurance programs. Tolerances of ± 15% for CTDIvol and ± 5% for image noise relative to baseline values should be used. © 2016 The Authors

Experimental and numerical investigation of the nonlinear dynamics of compliant mechanisms for deployable structures

NASA Astrophysics Data System (ADS)

Dewalque, Florence; Schwartz, Cédric; Denoël, Vincent; Croisier, Jean-Louis; Forthomme, Bénédicte; Brüls, Olivier

2018-02-01

This paper studies the dynamics of tape springs which are characterised by a highly geometrical nonlinear behaviour including buckling, the formation of folds and hysteresis. An experimental set-up is designed to capture these complex nonlinear phenomena. The experimental data are acquired by the means of a 3D motion analysis system combined with a synchronised force plate. Deployment tests show that the motion can be divided into three phases characterised by different types of folds, frequencies of oscillation and damping behaviours. Furthermore, the reproducibility quality of the dynamic and quasi-static results is validated by performing a large number of tests. In parallel, a nonlinear finite element model is developed. The required model parameters are identified based on simple experimental tests such as static deformed configurations and small amplitude vibration tests. In the end, the model proves to be well correlated with the experimental results in opposite sense bending, while in equal sense, both the experimental set-up and the numerical model are particularly sensitive to the initial conditions.

Recent advance to 3 × 10(-5) rad near diffraction-limited beam divergence of dye laser with transverse-discharge flash-lamp pumping.

PubMed

Trusov, K K

1994-02-20

A new experimental setup of a Rhodamine 6G dye laser with a transverse-discharge flash-lamp-pumping system is presented. It differs from a previous setup [Sov. J. Quantum Electron. 16, 468-471 (1989)] in that it has a larger laser beam aperture (32 mm) and higher pumping energy (1 kJ), which made it possible to test the scalability and reach near diffraction-limited laser beam divergence of 3 × 10(-5) rad FWHM at beam energy 1.4 J. The effect of spectral dispersion in the active medium and of other optical elements on the beam divergence is also discussed.

Measuring the effect of spray plume angle on the accuracy of droplet size data

USDA-ARS?s Scientific Manuscript database

Analysis of droplet size data using laser diffraction allows for quick and easy assessment of droplet size for agricultural spray nozzles and pesticides; however, operation and setup of the instrument and test system can potentially influence the accuracy of the data. One of the factors is the orie...

Within-band spray distribution of nozzles used for herbaceous plant control

Treesearch

James H. Miller

1994-01-01

Abstract. Described are the spray patterns of nozzles setup for banded herbaceous plant control treatments. Spraying Systems Company nozzles. were tested, but similar nozzles are available from other manufacturers. Desirable traits were considered to be as follows: an even distribution pattern, low volume, low height, large droplets, and a single...

Critical Current Test of Liquid Hydrogen Cooled HTC Superconductors under External Magnetic Field

NASA Astrophysics Data System (ADS)

Shirai, Yasuyuki; Shiotsu, Masahiro; Tatsumoto, Hideki; Kobayashi, Hiroaki; Naruo, Yoshihiro; Nonaka, Satoshi; Inatani, Yoshifumi

High-Tc (HTC) superconductors including MgB2 will show excellent properties under temperature of Liquid Hydrogen (LH2:20K), which has large latent heat and low viscosity coefficient. In order to design and fabricate the LH2 cooled superconducting energy devices, we must clear the cooling property of LH2 for superconductors, the cooling system and safety design of LH2 cooled superconducting devices and electro-magnetic property evaluation of superconductors (BSCCO, REBCO and MgB2) and their magnets cooled by LH2. As the first step of the study, an experimental setup which can be used for investigating heat transfer characteristics of LH2 in a pool and also in forced flow (circulation loop with a pump), and also for evaluation of electro-magnetic properties of LH2 cooled superconductors under external magnetic field (up to 7 T). In this paper, we will show a short sketch of the experimental set-up, practical experiences in safety operation of liquid hydrogen cooling system and example test results of critical current evaluation of HTC superconductors cooled by LH2.

Development of a pyramidal wavefront sensor test-bench at INO

NASA Astrophysics Data System (ADS)

Turbide, Simon; Wang, Min; Gauvin, Jonny; Martin, Olivier; Savard, Maxime; Bourqui, Pascal; Veran, Jean-Pierre; Deschenes, William; Anctil, Genevieve; Chateauneuf, François

2013-12-01

The key technical element of the adaptive optics in astronomy is the wavefront sensing (WFS). One of the advantages of the pyramid wavefront sensor (P-WFS) over the widely used Shack-Hartmann wavefront sensor seems to be the increased sensitivity in closed-loop applications. A high-sensitivity and large dynamic-range WFS, such as P-WFS technology, still needs to be further investigated for proper justification in future Extremely Large Telescopes application. At INO, we have recently carried out the optical design, testing and performance evaluation of a P-WFS bench setup. The optical design of the bench setup mainly consists of the super-LED fiber source, source collimator, spatial light modulator (SLM), relay lenses, tip-tilt mirror, Fourier-transforming lens, and a four-faceted glass pyramid with a large vertex angle as well as pupil re-imaged optics. The phase-only SLM has been introduced in the bench setup to generate atmospheric turbulence with a maximum phase shift of more than 2π at each pixel (256 grey levels). Like a modified Foucault knife-edge test, the refractive pyramid element is used to produce four images of the entrance pupil on a CCD camera. The Fourier-transforming lens, which is used before the pyramid prism, is designed for telecentric output to allow dynamic modulation (rotation of the beam around the pyramid-prism center) from a tip-tilt mirror. Furthermore, a P-WFS diffraction-based model has been developed. This model includes most of the system limitations such as the SLM discrete voltage steps and the CCD pixel pitch. The pyramid effects (edges and tip) are considered as well. The modal wavefront reconstruction algorithm relies on the construction of an interaction matrix (one for each modulation's amplitude). Each column of the interaction matrix represents the combination of the four pupil images for a given wavefront aberration. The nice agreement between the data and the model suggest that the limitation of the system is not the P-WFS itself, but rather its environment such as source intensity fluctuation and vibration of the optical bench. Finally, the phase-reconstruction errors of the P-WFS have been compared to those of a Shack-Hartmann, showing the regions of interest of the former system. The bench setup will be focusing on the astronomy application as well as commercial applications, such as bio-medical application etc.

Feedforward operation of a lens setup for large defocus and astigmatism correction

NASA Astrophysics Data System (ADS)

Verstraete, Hans R. G. W.; Almasian, MItra; Pozzi, Paolo; Bilderbeek, Rolf; Kalkman, Jeroen; Faber, Dirk J.; Verhaegen, Michel

2016-04-01

In this manuscript, we present a lens setup for large defocus and astigmatism correction. A deformable defocus lens and two rotational cylindrical lenses are used to control the defocus and astigmatism. The setup is calibrated using a simple model that allows the calculation of the lens inputs so that a desired defocus and astigmatism are actuated on the eye. The setup is tested by determining the feedforward prediction error, imaging a resolution target, and removing introduced aberrations.

Laser-induced transient grating setup with continuously tunable period

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vega-Flick, A.; Applied Physics Department, CINVESTAV-Unidad Mérida, Carretera Antigua a Progreso Km 6, Cordemex, Mérida, Yucatán 97310 Mexico; Eliason, J. K.

2015-12-15

We present a modification of the laser-induced transient grating setup enabling continuous tuning of the transient grating period. The fine control of the period is accomplished by varying the angle of the diffraction grating used to split excitation and probe beams. The setup has been tested by measuring dispersion of bulk and surface acoustic waves in both transmission and reflection geometries. The presented modification is fully compatible with optical heterodyne detection and can be easily implemented in any transient grating setup.

Ground vibration test results for Drones for Aerodynamic and Structural Testing (DAST)/Aeroelastic Research Wing (ARW-1R) aircraft

NASA Technical Reports Server (NTRS)

Cox, T. H.; Gilyard, G. B.

1986-01-01

The drones for aerodynamic and structural testing (DAST) project was designed to control flutter actively at high subsonic speeds. Accurate knowledge of the structural model was critical for the successful design of the control system. A ground vibration test was conducted on the DAST vehicle to determine the structural model characteristics. This report presents and discusses the vibration and test equipment, the test setup and procedures, and the antisymmetric and symmetric mode shape results. The modal characteristics were subsequently used to update the structural model employed in the control law design process.

The detection error of thermal test low-frequency cable based on M sequence correlation algorithm

NASA Astrophysics Data System (ADS)

Wu, Dongliang; Ge, Zheyang; Tong, Xin; Du, Chunlin

2018-04-01

The problem of low accuracy and low efficiency of off-line detecting on thermal test low-frequency cable faults could be solved by designing a cable fault detection system, based on FPGA export M sequence code(Linear feedback shift register sequence) as pulse signal source. The design principle of SSTDR (Spread spectrum time-domain reflectometry) reflection method and hardware on-line monitoring setup figure is discussed in this paper. Testing data show that, this detection error increases with fault location of thermal test low-frequency cable.

Reliable measurement of E. coli single cell fluorescence distribution using a standard microscope set-up.

PubMed

Cortesi, Marilisa; Bandiera, Lucia; Pasini, Alice; Bevilacqua, Alessandro; Gherardi, Alessandro; Furini, Simone; Giordano, Emanuele

2017-01-01

Quantifying gene expression at single cell level is fundamental for the complete characterization of synthetic gene circuits, due to the significant impact of noise and inter-cellular variability on the system's functionality. Commercial set-ups that allow the acquisition of fluorescent signal at single cell level (flow cytometers or quantitative microscopes) are expensive apparatuses that are hardly affordable by small laboratories. A protocol that makes a standard optical microscope able to acquire quantitative, single cell, fluorescent data from a bacterial population transformed with synthetic gene circuitry is presented. Single cell fluorescence values, acquired with a microscope set-up and processed with custom-made software, are compared with results that were obtained with a flow cytometer in a bacterial population transformed with the same gene circuitry. The high correlation between data from the two experimental set-ups, with a correlation coefficient computed over the tested dynamic range > 0.99, proves that a standard optical microscope- when coupled with appropriate software for image processing- might be used for quantitative single-cell fluorescence measurements. The calibration of the set-up, together with its validation, is described. The experimental protocol described in this paper makes quantitative measurement of single cell fluorescence accessible to laboratories equipped with standard optical microscope set-ups. Our method allows for an affordable measurement/quantification of intercellular variability, whose better understanding of this phenomenon will improve our comprehension of cellular behaviors and the design of synthetic gene circuits. All the required software is freely available to the synthetic biology community (MUSIQ Microscope flUorescence SIngle cell Quantification).

Measuring the Blast and Ballistic Performance of Armor

DTIC Science & Technology

2015-10-15

Typical ballistic test instrumentation is depicted in Fig. 1. The gun system employs a Mann barrel , available in a range of calibers1 (e.g., .22 cal...setup. (A) Mann barrel gun system; (B) computer and data acquisition interface; (C) remote, manual trigger; (D) velocity screens; (E) high speed video...1 Caliber corresponds to the diameter of the gun barrel , usually expressed in inches; e.g., .30 cal

Fire Resistant Aircraft Hydraulic System.

DTIC Science & Technology

1982-07-01

Chemical Division "Fluorinert" FC-48 - Fluorinated Hydrocarbon "Fluorinert" FC-70 - Fluorinated Hydrocarbon Montedison S. p. A. "Fomblin" Z-04...forming substances such as varnish which could seize a spool valve or other small-clearance sliding surfaces. The test setup is pictorially described in...breakdown products such as solid particles, gels, and sludge’can plug system filters and even small fluid passages, nozzles, and orifices. Varnish -like

3D video-based deformation measurement of the pelvis bone under dynamic cyclic loading

PubMed Central

2011-01-01

Background Dynamic three-dimensional (3D) deformation of the pelvic bones is a crucial factor in the successful design and longevity of complex orthopaedic oncological implants. The current solutions are often not very promising for the patient; thus it would be interesting to measure the dynamic 3D-deformation of the whole pelvic bone in order to get a more realistic dataset for a better implant design. Therefore we hypothesis if it would be possible to combine a material testing machine with a 3D video motion capturing system, used in clinical gait analysis, to measure the sub millimetre deformation of a whole pelvis specimen. Method A pelvis specimen was placed in a standing position on a material testing machine. Passive reflective markers, traceable by the 3D video motion capturing system, were fixed to the bony surface of the pelvis specimen. While applying a dynamic sinusoidal load the 3D-movement of the markers was recorded by the cameras and afterwards the 3D-deformation of the pelvis specimen was computed. The accuracy of the 3D-movement of the markers was verified with 3D-displacement curve with a step function using a manual driven 3D micro-motion-stage. Results The resulting accuracy of the measurement system depended on the number of cameras tracking a marker. The noise level for a marker seen by two cameras was during the stationary phase of the calibration procedure ± 0.036 mm, and ± 0.022 mm if tracked by 6 cameras. The detectable 3D-movement performed by the 3D-micro-motion-stage was smaller than the noise level of the 3D-video motion capturing system. Therefore the limiting factor of the setup was the noise level, which resulted in a measurement accuracy for the dynamic test setup of ± 0.036 mm. Conclusion This 3D test setup opens new possibilities in dynamic testing of wide range materials, like anatomical specimens, biomaterials, and its combinations. The resulting 3D-deformation dataset can be used for a better estimation of material characteristics of the underlying structures. This is an important factor in a reliable biomechanical modelling and simulation as well as in a successful design of complex implants. PMID:21762533

KSC-07pd1494

NASA Image and Video Library

2007-06-13

KENNEDY SPACE CENTER, FLA. -- Another view of the area of orbiter Endeavour's orbital maneuvering system, or OMS, pod where the tear occurred on Atlantis during launch of mission STS-117 on June 8, 2007. Repair is under consideration following testing at KSC and Houston. The test articles each feature three tiles (Low Temperature Reusable Surface Insulation, or LRSI) affixed next to two FIB blankets, simulating the thermal protection system set-up on Atlantis' OMS pod in the vicinity of the in-flight anomaly. These test articles were flown to Texas the morning of June 14. The TPS team at KSC has also provided a total of 22 FIB samples for other testing and analysis. Photo credit: NASA/Kim Shiflett

KSC-07pd1495

NASA Image and Video Library

2007-06-13

KENNEDY SPACE CENTER, FLA. -- Another view of the area of orbiter Endeavour's orbital maneuvering system, or OMS, pod where the tear occurred on Atlantis during launch of mission STS-117 on June 8, 2007. Repair is under consideration following testing at KSC and Houston. The test articles each feature three tiles (Low Temperature Reusable Surface Insulation, or LRSI) affixed next to two FIB blankets, simulating the thermal protection system set-up on Atlantis' OMS pod in the vicinity of the in-flight anomaly. These test articles were flown to Texas the morning of June 14. The TPS team at KSC has also provided a total of 22 FIB samples for other testing and analysis. Photo credit: NASA/Kim Shiflett

Accurate and fast creep test for viscoelastic fluids using disk-probe-type and quadrupole-arrangement-type electromagnetically spinning systems

NASA Astrophysics Data System (ADS)

Hirano, Taichi; Sakai, Keiji

2017-07-01

Viscoelasticity is a unique characteristic of soft materials and describes its dynamic response to mechanical stimulations. A creep test is an experimental method for measuring the strain ratio/rate against an applied stress, thereby assessing the viscoelasticity of the materials. We propose two advanced experimental systems suitable for the creep test, adopting our original electromagnetically spinning (EMS) technique. This technique can apply a constant torque by a noncontact mechanism, thereby allowing more sensitive and rapid measurements. The viscosity and elasticity of a semidilute wormlike micellar solution were determined using two setups, and the consistency between the results was assessed.

MO-G-BRE-03: Automated Continuous Monitoring of Patient Setup with Second-Check Independent Image Registration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jiang, X; Fox, T; Schreibmann, E

2014-06-15

Purpose: To create a non-supervised quality assurance program to monitor image-based patient setup. The system acts a secondary check by independently computing shifts and rotations and interfaces with Varian's database to verify therapist's work and warn against sub-optimal setups. Methods: Temporary digitally-reconstructed radiographs (DRRs) and OBI radiographic image files created by Varian's treatment console during patient setup are intercepted and used as input in an independent registration module customized for accuracy that determines the optimal rotations and shifts. To deal with the poor quality of OBI images, a histogram equalization of the live images to the DDR counterparts is performedmore » as a pre-processing step. A search for the most sensitive metric was performed by plotting search spaces subject to various translations and convergence analysis was applied to ensure the optimizer finds the global minima. Final system configuration uses the NCC metric with 150 histogram bins and a one plus one optimizer running for 2000 iterations with customized scales for translations and rotations in a multi-stage optimization setup that first corrects and translations and subsequently rotations. Results: The system was installed clinically to monitor and provide almost real-time feedback on patient positioning. On a 2 month-basis uncorrected pitch values were of a mean 0.016° with standard deviation of 1.692°, and couch rotations of − 0.090°± 1.547°. The couch shifts were −0.157°±0.466° cm for the vertical, 0.045°±0.286 laterally and 0.084°± 0.501° longitudinally. Uncorrected pitch angles were the most common source of discrepancies. Large variations in the pitch angles were correlated with patient motion inside the mask. Conclusion: A system for automated quality assurance of therapist's registration was designed and tested in clinical practice. The approach complements the clinical software's automated registration in terms of algorithm configuration and performance and constitutes a practical approach to implement safe and cost-effective radiotherapy.« less

Cryogenic actuator testing for the SAFARI ground calibration setup

NASA Astrophysics Data System (ADS)

de Jonge, C.; Eggens, M.; Nieuwenhuizen, A. C. T.; Detrain, A.; Smit, H.; Dieleman, P.

2012-09-01

For the on-ground calibration setup of the SAFARI instrument cryogenic mechanisms are being developed at SRON Netherlands Institute for Space Research, including a filter wheel, XYZ-scanner and a flipmirror mechanism. Due to the extremely low background radiation requirement of the SAFARI instrument, all of these mechanisms will have to perform their work at 4.5 Kelvin and low-dissipative cryogenic actuators are required to drive these mechanisms. In this paper, the performance of stepper motors, piezoelectric actuators and brushless DC-motors as cryogenic actuators are compared. We tested stepper motor mechanical performance and electrical dissipation at 4K. The actuator requirements, test setup and test results are presented. Furthermore, design considerations and early performance tests of the flipmirror mechanism are discussed. This flipmirror features a 102 x 72 mm aluminum mirror that can be rotated 45°. A Phytron stepper motor with reduction gearbox has been chosen to drive the flipmirror. Testing showed that this motor has a dissipation of 49mW at 4K with a torque of 60Nmm at 100rpm. Thermal modeling of the flipmirror mechanism predicts that with proper thermal strapping the peak temperature of the flipmirror after a single action will be within the background level requirements of the SAFARI instrument. Early tests confirm this result. For low-duty cycle operations commercial stepper motors appear suitable as actuators for test equipment in the SAFARI on ground calibration setup.

Comparison of six electromyography acquisition setups on hand movement classification tasks

PubMed Central

Pizzolato, Stefano; Tagliapietra, Luca; Cognolato, Matteo; Reggiani, Monica; Müller, Henning

2017-01-01

Hand prostheses controlled by surface electromyography are promising due to the non-invasive approach and the control capabilities offered by machine learning. Nevertheless, dexterous prostheses are still scarcely spread due to control difficulties, low robustness and often prohibitive costs. Several sEMG acquisition setups are now available, ranging in terms of costs between a few hundred and several thousand dollars. The objective of this paper is the relative comparison of six acquisition setups on an identical hand movement classification task, in order to help the researchers to choose the proper acquisition setup for their requirements. The acquisition setups are based on four different sEMG electrodes (including Otto Bock, Delsys Trigno, Cometa Wave + Dormo ECG and two Thalmic Myo armbands) and they were used to record more than 50 hand movements from intact subjects with a standardized acquisition protocol. The relative performance of the six sEMG acquisition setups is compared on 41 identical hand movements with a standardized feature extraction and data analysis pipeline aimed at performing hand movement classification. Comparable classification results are obtained with three acquisition setups including the Delsys Trigno, the Cometa Wave and the affordable setup composed of two Myo armbands. The results suggest that practical sEMG tests can be performed even when costs are relevant (e.g. in small laboratories, developing countries or use by children). All the presented datasets can be used for offline tests and their quality can easily be compared as the data sets are publicly available. PMID:29023548

Comparison of six electromyography acquisition setups on hand movement classification tasks.

PubMed

Pizzolato, Stefano; Tagliapietra, Luca; Cognolato, Matteo; Reggiani, Monica; Müller, Henning; Atzori, Manfredo

2017-01-01

Hand prostheses controlled by surface electromyography are promising due to the non-invasive approach and the control capabilities offered by machine learning. Nevertheless, dexterous prostheses are still scarcely spread due to control difficulties, low robustness and often prohibitive costs. Several sEMG acquisition setups are now available, ranging in terms of costs between a few hundred and several thousand dollars. The objective of this paper is the relative comparison of six acquisition setups on an identical hand movement classification task, in order to help the researchers to choose the proper acquisition setup for their requirements. The acquisition setups are based on four different sEMG electrodes (including Otto Bock, Delsys Trigno, Cometa Wave + Dormo ECG and two Thalmic Myo armbands) and they were used to record more than 50 hand movements from intact subjects with a standardized acquisition protocol. The relative performance of the six sEMG acquisition setups is compared on 41 identical hand movements with a standardized feature extraction and data analysis pipeline aimed at performing hand movement classification. Comparable classification results are obtained with three acquisition setups including the Delsys Trigno, the Cometa Wave and the affordable setup composed of two Myo armbands. The results suggest that practical sEMG tests can be performed even when costs are relevant (e.g. in small laboratories, developing countries or use by children). All the presented datasets can be used for offline tests and their quality can easily be compared as the data sets are publicly available.

Design and development of new collimator cones for fractionated stereotactic radiation therapy in Samsung Medical Center.

PubMed

Ahn, Y C; Ju, S G; Kim, D Y; Choi, D R; Huh, S J; Park, Y H; Lim, D H; Kim, M K

1999-05-01

In stereotactic radiotherapy using X-Knife system, the commercially supplied collimator cone system had a few mechanical limitations. The authors have developed new collimator cones to overcome these limitations and named them "SMC type" collimator cones. We made use of cadmium-free cerrobend alloy within the stainless steel cylinder housing. We made nine cones of relatively larger sizes (3.0 cm to 7.0 cm in diameter) and of shorter length with bigger clearance from the isocenter than the commercial cones. The cone housing and the collimator cones were designed to insert into the wedge mount of the gantry head to enable double-exposure linac-gram taking. The mechanical accuracy of pointing to the isocenter was tested by ball test and cone rotation test, and the dosimetric measurements were performed, all of which were with satisfactory results. A new innovative quality assurance procedure using linac-grams on the patients at the actual treatment setup was attempted after taking 10 sets of AP and lateral linac-grams and the overall mechanical isocenter accuracy was excellent (average error = 0.4 +/- 0.2 mm). We have developed the SMC type collimator cone system mainly for fractionated stereotactic radiation therapy use with our innovative ideas. The new cones' mechanical accuracy and physical properties were satisfactory for clinical use, and the verification of the isocenter accuracy on the actual treatment setup has become possible.

Timing system for firing widely spaced test nuclear detonations

NASA Technical Reports Server (NTRS)

Partridge, Ralph E.

1992-01-01

The national weapons design laboratories (Los Alamos National Laboratory and Lawrence Livermore National Laboratory) test fire nuclear devices at the Nevada Test Site (NTS), which is spread over an area of over 1200 square miles. On each test there are hundreds of high time resolution recordings made of nuclear output waveforms and other phenomena. In order to synchronize these recordings with each other, with the nuclear device, and with offsite recordings, there is a requirement that the permanent command center and the outlying temporary firing sites be time tied to each other and to UTC to permit firing the shot at a predetermined time with an accuracy of about a microsecond. Various aspects of the test setup and timing system are discussed.

ATON (Autonomous Terrain-based Optical Navigation) for exploration missions: recent flight test results

NASA Astrophysics Data System (ADS)

Theil, S.; Ammann, N.; Andert, F.; Franz, T.; Krüger, H.; Lehner, H.; Lingenauber, M.; Lüdtke, D.; Maass, B.; Paproth, C.; Wohlfeil, J.

2018-03-01

Since 2010 the German Aerospace Center is working on the project Autonomous Terrain-based Optical Navigation (ATON). Its objective is the development of technologies which allow autonomous navigation of spacecraft in orbit around and during landing on celestial bodies like the Moon, planets, asteroids and comets. The project developed different image processing techniques and optical navigation methods as well as sensor data fusion. The setup—which is applicable to many exploration missions—consists of an inertial measurement unit, a laser altimeter, a star tracker and one or multiple navigation cameras. In the past years, several milestones have been achieved. It started with the setup of a simulation environment including the detailed simulation of camera images. This was continued by hardware-in-the-loop tests in the Testbed for Robotic Optical Navigation (TRON) where images were generated by real cameras in a simulated downscaled lunar landing scene. Data were recorded in helicopter flight tests and post-processed in real-time to increase maturity of the algorithms and to optimize the software. Recently, two more milestones have been achieved. In late 2016, the whole navigation system setup was flying on an unmanned helicopter while processing all sensor information onboard in real time. For the latest milestone the navigation system was tested in closed-loop on the unmanned helicopter. For that purpose the ATON navigation system provided the navigation state for the guidance and control of the unmanned helicopter replacing the GPS-based standard navigation system. The paper will give an introduction to the ATON project and its concept. The methods and algorithms of ATON are briefly described. The flight test results of the latest two milestones are presented and discussed.

SU-F-P-23: Setup Uncertainties for the Lung Stereotactic Body Radiation Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Q; Vigneri, P; Madu, C

2016-06-15

Purpose: The Exactrack X-ray system with six degree-of-freedom (6DoF) adjustment ability can be used for setup of lung stereotactic body radiation therapy. The setup uncertainties from ExacTrack 6D system were analyzed. Methods: The Exactrack X-ray 6D image guided radiotherapy system is used in our clinic. The system is an integration of 2 subsystems: (1): an infrared based optical position system and (2) a radiography kV x-ray imaging system. The infrared system monitors reflective body markers on the patient’s skin to assistant in the initial setup. The radiographic kV devices were used for patient positions verification and adjustment. The position verificationmore » was made by fusing the radiographs with the digitally reconstructed radiograph (DRR) images generated by simulation CT images using 6DoF fusion algorithms. Those results were recorded in our system. Gaussian functions were used to fit the data. Results: For 37 lung SBRT patients, the image registration results for the initial setup by using surface markers and for the verifications, were measured. The results were analyzed for 143 treatments. The mean values for the lateral, longitudinal, vertical directions were 0.1, 0.3 and 0.3mm, respectively. The standard deviations for the lateral, longitudinal and vertical directions were 0.62, 0.78 and 0.75mm respectively. The mean values for the rotations around lateral, longitudinal and vertical directions were 0.1, 0.2 and 0.4 degrees respectively, with standard deviations of 0.36, 0.34, and 0.42 degrees. Conclusion: The setup uncertainties for the lung SBRT cases by using Exactrack 6D system were analyzed. The standard deviations of the setup errors were within 1mm for all three directions, and the standard deviations for rotations were within 0.5 degree.« less

Totomatix: a novel automatic set-up to control diurnal, diel and long-term plant nitrate nutrition

PubMed Central

Adamowicz, Stéphane; Le Bot, Jacques; Huanosto Magaña, Ruth; Fabre, José

2012-01-01

Background Stand-alone nutritional set-ups are useful tools to grow plants at defined nutrient availabilities and to measure nutrient uptake rates continuously, in particular that for nitrate. Their use is essential when the measurements are meant to cover long time periods. These complex systems have, however, important drawbacks, including poor long-term reliability and low precision at high nitrate concentration. This explains why the information dealing with diel dynamics of nitrate uptake rate is scarce and concerns mainly young plants grown at low nitrate concentration. Scope The novel system detailed in this paper has been developed to allow versatile use in growth rooms, greenhouses or open fields at nitrate concentrations ranging from a few micro- to several millimoles per litres. The system controls, at set frequencies, the solution nitrate concentration, pH and volumes. Nitrate concentration is measured by spectral deconvolution of UV spectra. The main advantages of the set-up are its low maintenance (weekly basis), an ability to diagnose interference or erroneous analyses and high precision of nitrate concentration measurements (0·025 % at 3 mm). The paper details the precision of diurnal nitrate uptake rate measurements, which reveals sensitivity to solution volume at low nitrate concentration, whereas at high concentration, it is mostly sensitive to the precision of volume estimates. Conclusions This novel set-up allows us to measure and characterize the dynamics of plant nitrate nutrition at high temporal resolution (minutes to hours) over long-term experiments (up to 1 year). It is reliable and also offers a novel method to regulate up to seven N treatments by adjusting the daily uptake of test plants relative to controls, in variable environments such as open fields and glasshouses. PMID:21985796

Solar electric propulsion thrust subsystem development

NASA Technical Reports Server (NTRS)

Masek, T. D.

1973-01-01

The Solar Electric Propulsion System developed under this program was designed to demonstrate all the thrust subsystem functions needed on an unmanned planetary vehicle. The demonstration included operation of the basic elements, power matching input and output voltage regulation, three-axis thrust vector control, subsystem automatic control including failure detection and correction capability (using a PDP-11 computer), operation of critical elements in thermal-vacuum-, zero-gravity-type propellant storage, and data outputs from all subsystem elements. The subsystem elements, functions, unique features, and test setup are described. General features and capabilities of the test-support data system are also presented. The test program culminated in a 1500-h computer-controlled, system-functional demonstration. This included simultaneous operation of two thruster/power conditioner sets. The results of this testing phase satisfied all the program goals.

Design ATE systems for complex assemblies

NASA Astrophysics Data System (ADS)

Napier, R. S.; Flammer, G. H.; Moser, S. A.

1983-06-01

The use of ATE systems in radio specification testing can reduce the test time by approximately 90 to 95 percent. What is more, the test station does not require a highly trained operator. Since the system controller has full power over all the measurements, human errors are not introduced into the readings. The controller is immune to any need to increase output by allowing marginal units to pass through the system. In addition, the software compensates for predictable, repeatable system errors, for example, cabling losses, which are an inherent part of the test setup. With no variation in test procedures from unit to unit, there is a constant repeatability factor. Preparing the software, however, usually entails considerable expense. It is pointed out that many of the problems associated with ATE system software can be avoided with the use of a software-intensive, or computer-intensive, system organization. Its goal is to minimize the user's need for software development, thereby saving time and money.

Solar powered automobile automation for heatstroke prevention

NASA Astrophysics Data System (ADS)

Singh, Navtej Swaroop; Sharma, Ishan; Jangid, Santosh

2016-03-01

Heatstroke inside a car has been critical problem in every part of the world. Non-exertional heat stroke results from exposure to a high environmental temperature. Exertional heat stroke happens from strenuous exercise. This paper presents a solution for this fatal problem and proposes an embedded solution, which is cost effective and shows the feasibility in implementation. The proposed system consists of information sharing platform, interfacing of sensors, Global System Mobile (GSM), real time monitoring system and the system is powered by the solar panel. The system has been simulated and tested with experimental setup.

Experimental assessment of eye protection efficiency against high speed projectiles.

PubMed

Speck, Alexis; Zelzer, Benedikt; Eppig, Timo; Langenbucher, Achim

2013-02-01

Work in hazardous zones with the risk of mechanical injuries requires protection with safety spectacles. Mechanical eye injuries with metal foreign bodies are often caused by rotational material machining or production processes with high pressure or high velocity moving parts. Normative regulations restrict to tests with small and fast flying objects (e.g. 6mm ball). The literature does not provide any information about protection capabilities against larger objects with high mass and arbitrary shape. The purpose of this study was to test the protection efficiency of safety spectacles against flying objects. The scope of this paper is to present a new test setup for mechanical impact resistance testing of personal protective eyewear against objects with arbitrary shape and mass. The setup is based on a catapult platform, accelerating a sliding carriage on a rail. A pull rope system allows velocities up to 62±2 m·s(-1). A photo sensor was used for velocity measurement. The carriage can be loaded with projectiles of up to 30mm×30mm×40mm in size with arbitrary orientation, depending on the carriage insert. Testing and validation was done with projectiles such as 7g metal chips and fragments with approximate dimensions of 10mm×15mm. Samples were standard occupational safety spectacles mounted on a test head. The projectile impact was captured with a monochrome high speed camera. The aiming accuracy test showed deviations of approximately 1mm of two impacts on the same spectacle surface with a free flight distance of 150mm. All tests with slow, medium and high speed projectiles showed no contact with the eye medium. Objects with velocities from 10 m·s(-1) to 62 m·s(-1) fired the spectacle off from the test head. The medium speed test cut off one side of the spectacle frame. The high speed test with 62±2 m·s(-1) cracked the polycarbonate shield. We describe a method for accelerating arbitrary objects up to 62 m·s(-1) and for aiming these objects on safety eyewear, mounted on a test head. The setup allows a variety of projectile shapes, orientations and velocities. The accuracy of velocity measurement is ± 2 m·s(-1) for high velocity (< ± 5%). Further studies will address optimization of this setup due to signs of wear and gliding properties of the carriage, wireless ignition and higher velocities. Copyright © 2012. Published by Elsevier GmbH.

Low-cost diffuse optical tomography for the classroom

NASA Astrophysics Data System (ADS)

Minagawa, Taisuke; Zirak, Peyman; Weigel, Udo M.; Kristoffersen, Anna K.; Mateos, Nicolas; Valencia, Alejandra; Durduran, Turgut

2012-10-01

Diffuse optical tomography (DOT) is an emerging imaging modality with potential applications in oncology, neurology, and other clinical areas. It allows the non-invasive probing of the tissue function using relatively inexpensive and safe instrumentation. An educational laboratory setup of a DOT system could be used to demonstrate how photons propagate through tissues, basics of medical tomography, and the concepts of multiple scattering and absorption. Here, we report a DOT setup that could be introduced to the advanced undergraduate or early graduate curriculum using inexpensive and readily available tools. The basis of the system is the LEGO Mindstorms NXT platform which controls the light sources, the detectors (photo-diodes), a mechanical 2D scanning platform, and the data acquisition. A basic tomographic reconstruction is implemented in standard numerical software, and 3D images are reconstructed. The concept was tested and developed in an educational environment that involved a high-school student and a group of post-doctoral fellows.

A technique for the measurement of organic aerosol hygroscopicity, oxidation level, and volatility distributions

NASA Astrophysics Data System (ADS)

Cain, Kerrigan P.; Pandis, Spyros N.

2017-12-01

Hygroscopicity, oxidation level, and volatility are three crucial properties of organic pollutants. This study assesses the feasibility of a novel measurement and analysis technique to determine these properties and establish their relationship. The proposed experimental setup utilizes a cloud condensation nuclei (CCN) counter to quantify hygroscopic activity, an aerosol mass spectrometer to measure the oxidation level, and a thermodenuder to evaluate the volatility. The setup was first tested with secondary organic aerosol (SOA) formed from the ozonolysis of α-pinene. The results of the first experiments indicated that, for this system, the less volatile SOA contained species that had on average lower O : C ratios and hygroscopicities. In this SOA system, both low- and high-volatility components can have comparable oxidation levels and hygroscopicities. The method developed here can be used to provide valuable insights about the relationships among organic aerosol hygroscopicity, oxidation level, and volatility.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cho, M; Kim, T; Kang, S

Purpose: The purpose of this work is to develop a new patient set-up monitoring system using force sensing resistor (FSR) sensors that can confirm pressure of contact surface and evaluate its feasibility. Methods: In this study, we focused on develop the patient set-up monitoring system to compensate for the limitation of existing optical based monitoring system, so the developed system can inform motion in the radiation therapy. The set-up monitoring system was designed consisting of sensor units (FSR sensor), signal conditioning devices (USB cable/interface electronics), a control PC, and a developed analysis software. The sensor unit was made by attachingmore » FSR sensor and dispersing pressure sponge to prevent error which is caused by concentrating specific point. Measured signal from the FSR sensor was sampled to arduino mega 2560 microcontroller, transferred to control PC by using serial communication. The measured data went through normalization process. The normalized data was displayed through the developed graphic user interface (GUI) software. The software was designed to display a single sensor unit intensity (maximum 16 sensors) and display 2D pressure distribution (using 16 sensors) according to the purpose. Results: Changes of pressure value according to motion was confirmed by the developed set-up monitoring system. Very small movement such as little physical change in appearance can be confirmed using a single unit and using 2D pressure distribution. Also, the set-up monitoring system can observe in real time. Conclusion: In this study, we developed the new set-up monitoring system using FSR sensor. Especially, we expect that the new set-up monitoring system is suitable for motion monitoring of blind area that is hard to confirm existing optical system and compensate existing optical based monitoring system. As a further study, an integrated system will be constructed through correlation of existing optical monitoring system. This work was supported by the Industrial R&D program of MOTIE/KEIT. [10048997, Development of the core technology for integrated therapy devices based on real-time MRI guided tumor tracking] and the Mid-career Researcher Program (2014R1A2A1A10050270) through the National Research Foundation of Korea funded by the Ministry of Science, ICT&Future Planning.« less

Experimental testing of impact force on rigid and flexible barriers - A comparison

NASA Astrophysics Data System (ADS)

Nagl, Georg; Hübl, Johannes; Chiari, Michael

2016-04-01

The Trattenbach endangers the main western railway track of Austria by floods and debris flows. Three check dams for debris retention were built in the proximal fan area several decades ago. With regard to an improvement of the protective function, these structures have to be renewed. The recent concept of the uppermost barrier is a type of an energy dissipation net structure, stopping debris flows with the ability of self-cleaning by subsequent floods or by machinery employment. The access to the basin is achieved through the slit when the net has been removed. This technical structure consists of a rigid open crown dam with a 4m wide slit. This slit is closed with a flexible net. To verify this protective system, 21 small scale experiments were conducted to test and optimize this new type of Slit Net Dam. To determine the forces on the barrier, in a first setup of experiments the impact forces on a rigid wall with 24 load cells were measured. In the second setup the slit barrier with the net was investigated. On four main cables the anchor forces were measured. In a further setup the basal distance between the channel and lowest net was varied. To study the emptying of the basin and the dosing effect on debris flows.

Accelerated Aging Experiments for Capacitor Health Monitoring and Prognostics

NASA Technical Reports Server (NTRS)

Kulkarni, Chetan S.; Celaya, Jose Ramon; Biswas, Gautam; Goebel, Kai

2012-01-01

This paper discusses experimental setups for health monitoring and prognostics of electrolytic capacitors under nominal operation and accelerated aging conditions. Electrolytic capacitors have higher failure rates than other components in electronic systems like power drives, power converters etc. Our current work focuses on developing first-principles-based degradation models for electrolytic capacitors under varying electrical and thermal stress conditions. Prognostics and health management for electronic systems aims to predict the onset of faults, study causes for system degradation, and accurately compute remaining useful life. Accelerated life test methods are often used in prognostics research as a way to model multiple causes and assess the effects of the degradation process through time. It also allows for the identification and study of different failure mechanisms and their relationships under different operating conditions. Experiments are designed for aging of the capacitors such that the degradation pattern induced by the aging can be monitored and analyzed. Experimental setups and data collection methods are presented to demonstrate this approach.

Modelling, Simulation and Construction of a DC/DC Boost Power Converter: A School Experimental System

ERIC Educational Resources Information Center

Silva-Ortigoza, R.; Silva-Ortigoza, G.; Hernandez-Guzman, V. M.; Saldana-Gonzalez, G.; Marcelino-Aranda, M.; Marciano-Melchor, M.

2012-01-01

We introduce a dc/dc boost power converter as a didactic prototype intended to support courses on electric circuit analysis experimentally. The corresponding mathematical model is obtained, the converter is designed and an experimental setup is described, constructed and tested. Simplicity of construction as well as low cost of components renders…

Multimodal Interaction with Speech, Gestures and Haptic Feedback in a Media Center Application

NASA Astrophysics Data System (ADS)

Turunen, Markku; Hakulinen, Jaakko; Hella, Juho; Rajaniemi, Juha-Pekka; Melto, Aleksi; Mäkinen, Erno; Rantala, Jussi; Heimonen, Tomi; Laivo, Tuuli; Soronen, Hannu; Hansen, Mervi; Valkama, Pellervo; Miettinen, Toni; Raisamo, Roope

We demonstrate interaction with a multimodal media center application. Mobile phone-based interface includes speech and gesture input and haptic feedback. The setup resembles our long-term public pilot study, where a living room environment containing the application was constructed inside a local media museum allowing visitors to freely test the system.

Adaptive Multi-Layer LMS Controller Design and Application to Active Vibration Suppression on a Truss and Proposed Impact Analysis Technique

DTIC Science & Technology

2001-06-01

Setup and Initiation ........................................................ 83 2. Simulation 1 (19 Hz, Y-axis of Node 18, Piezo #2...175 INITIAL DISTRIBUTION LIST ................................................................................... 187 ix...system for the sake of testing and simplicity. The Adaptive Multi-Layered LMS Controller was developed one piece at a time. After initial experimental

EVA: laparoscopic instrument tracking based on Endoscopic Video Analysis for psychomotor skills assessment.

PubMed

Oropesa, Ignacio; Sánchez-González, Patricia; Chmarra, Magdalena K; Lamata, Pablo; Fernández, Alvaro; Sánchez-Margallo, Juan A; Jansen, Frank Willem; Dankelman, Jenny; Sánchez-Margallo, Francisco M; Gómez, Enrique J

2013-03-01

The EVA (Endoscopic Video Analysis) tracking system is a new system for extracting motions of laparoscopic instruments based on nonobtrusive video tracking. The feasibility of using EVA in laparoscopic settings has been tested in a box trainer setup. EVA makes use of an algorithm that employs information of the laparoscopic instrument's shaft edges in the image, the instrument's insertion point, and the camera's optical center to track the three-dimensional position of the instrument tip. A validation study of EVA comprised a comparison of the measurements achieved with EVA and the TrEndo tracking system. To this end, 42 participants (16 novices, 22 residents, and 4 experts) were asked to perform a peg transfer task in a box trainer. Ten motion-based metrics were used to assess their performance. Construct validation of the EVA has been obtained for seven motion-based metrics. Concurrent validation revealed that there is a strong correlation between the results obtained by EVA and the TrEndo for metrics, such as path length (ρ = 0.97), average speed (ρ = 0.94), or economy of volume (ρ = 0.85), proving the viability of EVA. EVA has been successfully validated in a box trainer setup, showing the potential of endoscopic video analysis to assess laparoscopic psychomotor skills. The results encourage further implementation of video tracking in training setups and image-guided surgery.

Laser Ignition Technology for Bi-Propellant Rocket Engine Applications

NASA Technical Reports Server (NTRS)

Thomas, Matt; Bossard, John; Early, Jim; Trinh, Huu; Dennis, Jay; Turner, James (Technical Monitor)

2001-01-01

This viewgraph presentation gives an overview of laser ignition technology for bipropellant rocket engines applications. The objectives of this project include: (1) the selection test chambers and flows; (2) definition of the laser ignition setup; (3) pulse format optimization; (4) fiber optic coupled laser ignition system analysis; and (5) chamber integration issues definition. The testing concludes that rocket combustion chamber laser ignition is imminent. Support technologies (multiplexing, window durability/cleaning, and fiber optic durability) are feasible.

AGARD Flight Test Techniques Series. Volume 9. Aircraft Exterior Noise Measurement and Analysis Techniques. (Le Bruit a l’Exterieur des Aeronefs: Techniques de Mesure et d’Analyse)

DTIC Science & Technology

1991-04-01

aircraft Fig. 4.6 Airborne test set-up to compare several microphone/nose-cone arrangements for self -noise generation on a glider plane Fig. 4.7 Comparison...of normalized self -noise spectra of ogive-nose-cone equipped condenser-microphones of different diameters F!g. 4.8 Frequency splitting in the noise...output is obtained at the last com-poet ot the sub-system. The electrical respose of the entire system is then the arithmetic Sof the ildividual respnsem

An ultrafast programmable electrical tester for enabling time-resolved, sub-nanosecond switching dynamics and programming of nanoscale memory devices.

PubMed

Shukla, Krishna Dayal; Saxena, Nishant; Manivannan, Anbarasu

2017-12-01

Recent advancements in commercialization of high-speed non-volatile electronic memories including phase change memory (PCM) have shown potential not only for advanced data storage but also for novel computing concepts. However, an in-depth understanding on ultrafast electrical switching dynamics is a key challenge for defining the ultimate speed of nanoscale memory devices that demands for an unconventional electrical setup, specifically capable of handling extremely fast electrical pulses. In the present work, an ultrafast programmable electrical tester (PET) setup has been developed exceptionally for unravelling time-resolved electrical switching dynamics and programming characteristics of nanoscale memory devices at the picosecond (ps) time scale. This setup consists of novel high-frequency contact-boards carefully designed to capture extremely fast switching transient characteristics within 200 ± 25 ps using time-resolved current-voltage measurements. All the instruments in the system are synchronized using LabVIEW, which helps to achieve various programming characteristics such as voltage-dependent transient parameters, read/write operations, and endurance test of memory devices systematically using short voltage pulses having pulse parameters varied from 1 ns rise/fall time and 1.5 ns pulse width (full width half maximum). Furthermore, the setup has successfully demonstrated strikingly one order faster switching characteristics of Ag 5 In 5 Sb 60 Te 30 (AIST) PCM devices within 250 ps. Hence, this novel electrical setup would be immensely helpful for realizing the ultimate speed limits of various high-speed memory technologies for future computing.

An ultrafast programmable electrical tester for enabling time-resolved, sub-nanosecond switching dynamics and programming of nanoscale memory devices

NASA Astrophysics Data System (ADS)

Shukla, Krishna Dayal; Saxena, Nishant; Manivannan, Anbarasu

2017-12-01

Recent advancements in commercialization of high-speed non-volatile electronic memories including phase change memory (PCM) have shown potential not only for advanced data storage but also for novel computing concepts. However, an in-depth understanding on ultrafast electrical switching dynamics is a key challenge for defining the ultimate speed of nanoscale memory devices that demands for an unconventional electrical setup, specifically capable of handling extremely fast electrical pulses. In the present work, an ultrafast programmable electrical tester (PET) setup has been developed exceptionally for unravelling time-resolved electrical switching dynamics and programming characteristics of nanoscale memory devices at the picosecond (ps) time scale. This setup consists of novel high-frequency contact-boards carefully designed to capture extremely fast switching transient characteristics within 200 ± 25 ps using time-resolved current-voltage measurements. All the instruments in the system are synchronized using LabVIEW, which helps to achieve various programming characteristics such as voltage-dependent transient parameters, read/write operations, and endurance test of memory devices systematically using short voltage pulses having pulse parameters varied from 1 ns rise/fall time and 1.5 ns pulse width (full width half maximum). Furthermore, the setup has successfully demonstrated strikingly one order faster switching characteristics of Ag5In5Sb60Te30 (AIST) PCM devices within 250 ps. Hence, this novel electrical setup would be immensely helpful for realizing the ultimate speed limits of various high-speed memory technologies for future computing.

SU-F-J-142: Proposed Method to Broaden Inclusion Potential of Patients Able to Use the Calypso Tracking System in Prostate Radiotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fiedler, D; Kuo, H; Bodner, W

2016-06-15

Purpose: To introduce a non-standard method of patient setup, using BellyBoard immobilization, to better utilize the localization and tracking potential of an RF-beacon system with EBRT for prostate cancer. Methods: An RF-beacon phantom was imaged using a wide bore CT scanner, both in a standard level position and with a known rotation (4° pitch and 7.5° yaw). A commercial treatment planning system (TPS) was used to determine positional coordinates of each beacon, and the centroid of the three beacons for both setups. For each setup at the Linac, kV AP and Rt Lateral images were obtained. A full characterization ofmore » the RF-beacon system in clinical mode was completed for various beacons’ array-to-centroid distances, which includes vertical, lateral, and longitudinal offset data, as well as pitch and yaw offset measurements for the tilted phantom. For the single patient who has been setup using the proposed BellyBoard method, a supine simulation was first obtained. When abdominal protrusion was found to be exceeding the limits of the RF-Beacon system through distance-based analysis in the TPS, the patient is re-simulated prone with the BellyBoard. Array to centroid distance is measured again in the TPS, and if found to be within the localization or tracking region it is applied. Results: Characterization of limitations for the RF-beacon system in clinical mode showed acceptable consistency of offset determination for phantom setup accuracy. The nonstandard patient setup method reduced the beacons’ centroid-to-array distance by 8.32cm, from 25.13cm to 16.81cm; completely out of tracking range (greater than 20cm) to within setup tracking range (less than 20cm). Conclusion: Using the RF-beacon system in combination with this novel patient setup can allow patients who would otherwise not be candidates for beacon enhanced EBRT to now be able to benefit from the reduced PTV margins of this treatment method.« less

Photocathode Optimization for a Dynamic Transmission Electron Microscope: Final Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ellis, P; Flom, Z; Heinselman, K

2011-08-04

The Dynamic Transmission Electron Microscope (DTEM) team at Harvey Mudd College has been sponsored by LLNL to design and build a test setup for optimizing the performance of the DTEM's electron source. Unlike a traditional TEM, the DTEM achieves much faster exposure times by using photoemission from a photocathode to produce electrons for imaging. The DTEM team's work is motivated by the need to improve the coherence and current density of the electron cloud produced by the electron gun in order to increase the image resolution and contrast achievable by DTEM. The photoemission test setup is nearly complete and themore » team will soon complete baseline tests of electron gun performance. The photoemission laser and high voltage power supply have been repaired; the optics path for relaying the laser to the photocathode has been finalized, assembled, and aligned; the internal setup of the vacuum chamber has been finalized and mostly implemented; and system control, synchronization, and data acquisition has been implemented in LabVIEW. Immediate future work includes determining a consistent alignment procedure to place the laser waist on the photocathode, and taking baseline performance measurements of the tantalum photocathode. Future research will examine the performance of the electron gun as a function of the photoemission laser profile, the photocathode material, and the geometry and voltages of the accelerating and focusing components in the electron gun. This report presents the team's progress and outlines the work that remains.« less

Airway humidification during high-frequency percussive ventilation.

PubMed

Allan, Patrick F; Hollingsworth, Michael J; Maniere, Gordon C; Rakofsky, Anthony K; Chung, Kevin K; Naworol, Gregory A; Ward, John A; Perello, Michelle; Morris, Michael J

2009-03-01

We were concerned about the risk of inadequate humidification during high-frequency percussive ventilation (HFPV). We studied 5 humidifiers during HFPV with a lung model, at bias gas flows of 10 L/min, 30 L/min, and 50 L/min, and compared the results to those from a comparator ventilator/humidifier setup and to the minimum temperature (30 degrees C) and humidity (30 mg/L) [corrected] recommended by the American Association for Respiratory Care, at both regular room temperature and a high ambient temperature. Temperature was measured at the humidifier outflow point and at the artificial carina. Humidity was measured at the artificial carina. Of the 7 HFPV/humidifier combinations, 2 (the MR850 at a bias flow of 50 L/min, and the ConchaTherm Hi-Flow with VDR nebulizer) provided a carinal temperature equivalent to the comparator setup at room temperature, whereas one HFPV/humidifier combination (the ConchaTherm Hi-Flow with modified programming, at bias flows of 30 L/min and 50 L/min) provided a higher carinal temperature. At high ambient temperature, all of the setups delivered lower carinal temperature than the comparator setup. Only 2 setups (the ConchaTherm with modified programming at a bias flow of 50 L/min, and the ConchaTherm Hi-Flow with VDR nebulizer) provided carinal humidification equivalent to the comparator setup, without regard to ambient temperature; the other humidifiers were less effective. The ConchaTherm with modified programming, and the ConchaTherm with the VDR nebulizer provided the most consistent humidification. HFPV's distinctive gas-flow mechanism may impair gas heating and humidification, so all humidification systems should be tested with HFPV prior to clinical use.

Application of genetic algorithm in integrated setup planning and operation sequencing

NASA Astrophysics Data System (ADS)

Kafashi, Sajad; Shakeri, Mohsen

2011-01-01

Process planning is an essential component for linking design and manufacturing process. Setup planning and operation sequencing is two main tasks in process planning. Many researches solved these two problems separately. Considering the fact that the two functions are complementary, it is necessary to integrate them more tightly so that performance of a manufacturing system can be improved economically and competitively. This paper present a generative system and genetic algorithm (GA) approach to process plan the given part. The proposed approach and optimization methodology analyses the TAD (tool approach direction), tolerance relation between features and feature precedence relations to generate all possible setups and operations using workshop resource database. Based on these technological constraints the GA algorithm approach, which adopts the feature-based representation, optimizes the setup plan and sequence of operations using cost indices. Case study show that the developed system can generate satisfactory results in optimizing the setup planning and operation sequencing simultaneously in feasible condition.

An experimental setup to characterize MR switched gradient-induced potentials.

PubMed

Fokapu, Odette; El-Tatar, Aziz

2013-06-01

We have developed an experimental setup as an in vitro research tool for studying the contamination of electrophysiological signals (EPS) by MRI environment; particularly, when due to the switched gradient-induced potentials. The system is composed of: 1) a MRI compatible module for the transmission of the EPS into the MRI tunnel, 2) a gelatin-based tissue-mimicking phantom, placed inside the tunnel, in which EPS is injected, 3) a detection module composed of a five input channel MRI compatible transmitter placed inside the tunnel, allowing an on-site pre-amplification of the bio-potentials and their transmission, via an optical fiber cable, to a four filtered output per channel receiver (350 Hz, 160 Hz, 80 Hz, and 40 Hz, for a total of 20 channels) placed in the control room, and 4) a signal processing algorithm used to analyze the generated induced potentials. A set of tests were performed to validate the electronic performances of the setup. We also present in this work an interesting application of the setup, i.e., the acquisition and analysis of the induced potentials with respect of the slice orientation for a given MRI sequence. Significant modifications of the time and frequency characteristics were observed with respect to axial, coronal or sagittal orientations.

A long arm for ultrasound: a combined robotic focused ultrasound setup for magnetic resonance-guided focused ultrasound surgery.

PubMed

Krafft, Axel J; Jenne, Jürgen W; Maier, Florian; Stafford, R Jason; Huber, Peter E; Semmler, Wolfhard; Bock, Michael

2010-05-01

Focused ultrasound surgery (FUS) is a highly precise noninvasive procedure to ablate pathogenic tissue. FUS therapy is often combined with magnetic resonance (MR) imaging as MR imaging offers excellent target identification and allows for continuous monitoring of FUS induced temperature changes. As the dimensions of the ultrasound (US) focus are typically much smaller than the targeted volume, multiple sonications and focus repositioning are interleaved to scan the focus over the target volume. Focal scanning can be achieved electronically by using phased-array US transducers or mechanically by using dedicated mechanical actuators. In this study, the authors propose and evaluate the precision of a combined robotic FUS setup to overcome some of the limitations of the existing MRgFUS systems. Such systems are typically integrated into the patient table of the MR scanner and thus only provide an application of the US wave within a limited spatial range from below the patient. The fully MR-compatible robotic assistance system InnoMotion (InnoMedic GmbH, Herxheim, Germany) was originally designed for MR-guided interventions with needles. It offers five pneumatically driven degrees of freedom and can be moved over a wide range within the bore of the magnet. In this work, the robotic system was combined with a fixed-focus US transducer (frequency: 1.7 MHz; focal length: 68 mm, and numerical aperture: 0.44) that was integrated into a dedicated, in-house developed treatment unit for FUS application. A series of MR-guided focal scanning procedures was performed in a polyacrylamide-egg white gel phantom to assess the positioning accuracy of the combined FUS setup. In animal experiments with a 3-month-old domestic pig, the system's potential and suitability for MRgFUS was tested. In phantom experiments, a total targeting precision of about 3 mm was found, which is comparable to that of the existing MRgFUS systems. Focus positioning could be performed within a few seconds. During in vivo experiments, a defined pattern of single thermal lesions and a therapeutically relevant confluent thermal lesion could be created. The creation of local tissue necrosis by coagulation was confirmed by post-FUS MR imaging and histological examinations on the treated tissue sample. During all sonications in phantom and in vivo, reliable MR imaging and online MR thermometry could be performed without compromises due to operation of the combined robotic FUS setup. Compared to the existing MRgFUS systems, the combined robotic FUS approach offers a wide range of spatial flexibility so that highly flexible application of the US wave would be possible, for example, to avoid risk structures within the US field. The setup might help to realize new ways of patient access in MRgFUS therapy. The setup is compatible with any closed-bore MR system and does not require an especially designed patient table.

Pure moment testing for spinal biomechanics applications: Fixed versus sliding ring cable-driven test designs.

PubMed

Eguizabal, Johnny; Tufaga, Michael; Scheer, Justin K; Ames, Christopher; Lotz, Jeffrey C; Buckley, Jenni M

2010-05-07

In vitro multi-axial bending testing using pure moment loading conditions has become the standard in evaluating the effects of different types of surgical intervention on spinal kinematics. Simple, cable-driven experimental set-ups have been widely adopted because they require little infrastructure. Traditionally, "fixed ring" cable-driven experimental designs have been used; however, there have been concerns with the validity of this set-up in applying pure moment loading. This study involved directly comparing the loading state induced by a traditional "fixed ring" apparatus versus a novel "sliding ring" approach. Flexion-extension bending was performed on an artificial spine model and a single cadaveric test specimen, and the applied loading conditions to the specimen were measured with an in-line multiaxial load cell. The results showed that the fixed ring system applies flexion-extension moments that are 50-60% less than the intended values. This design also imposes non-trivial anterior-posterior shear forces, and non-uniform loading conditions were induced along the length of the specimen. The results of this study indicate that fixed ring systems have the potential to deviate from a pure moment loading state and that our novel sliding ring modification corrects this error in the original test design. This suggests that the proposed sliding ring design should be used for future in vitro spine biomechanics studies involving a cable-driven pure moment apparatus. Copyright 2010 Elsevier Ltd. All rights reserved.

W-Band Free Space Permittivity Measurement Setup for Candidate Radome Materials

NASA Technical Reports Server (NTRS)

Fralick, Dion T.

1997-01-01

This paper presents a measurement system used for w-band complex permittivity measurements performed in NASA Langley Research Center's Electromagnetics Research Branch. The system was used to characterize candidate radome materials for the passive millimeter wave (PMMW) camera experiment. The PMMW camera is a new technology sensor, with goals of all-weather landings of civilian and military aircraft. The sensor is being developed under a NASA Technology Reinvestment program with TRW, McDonnell- Douglas, Honeywell, and Composite Optics, Inc. as participants. The experiment is scheduled to be flight tested on the Air Force's 'Speckled Trout' aircraft in late 1997. The camera operates at W-band, in a radiometric capacity and generates an image of the viewable field. Because the camera is a radiometer, the system is very sensitive to losses. Minimal transmission loss through the radome at the operating frequency, 89 GHz, was critical to the success of the experiment. This paper details the design, set-up, calibration and operation of a free space measurement system developed and used to characterize the candidate radome materials for this program.

1550 nm superluminescent diode and anti-Stokes effect CCD camera based optical coherence tomography for full-field optical metrology

NASA Astrophysics Data System (ADS)

Kredzinski, Lukasz; Connelly, Michael J.

2011-06-01

Optical Coherence Tomography (OCT) is a promising non-invasive imaging technology capable of carrying out 3D high-resolution cross-sectional images of the internal microstructure of examined material. However, almost all of these systems are expensive, requiring the use of complex optical setups, expensive light sources and complicated scanning of the sample under test. In addition most of these systems have not taken advantage of the competitively priced optical components available at wavelength within the main optical communications band located in the 1550 nm region. A comparatively simple and inexpensive full-field OCT system (FF-OCT), based on a superluminescent diode (SLD) light source and anti-stokes imaging device was constructed, to perform 3D cross-sectional imaging. This kind of inexpensive setup with moderate resolution could be easily applicable in low-level biomedical and industrial diagnostics. This paper involves calibration of the system and determines its suitability for imaging structures of biological tissues such as teeth, which has low absorption at 1550 nm.

Miniature wireless recording and stimulation system for rodent behavioural testing

NASA Astrophysics Data System (ADS)

Pinnell, R. C.; Dempster, J.; Pratt, J.

2015-12-01

Objective. Elucidation of neural activity underpinning rodent behaviour has traditionally been hampered by the use of tethered systems and human involvement. Furthermore the combination of deep-brain stimulation (DBS) and various neural recording modalities can lead to complex and time-consuming laboratory setups. For studies of this type, novel tools are required to drive forward this research. Approach. A miniature wireless system weighing 8.5 g (including battery) was developed for rodent use that combined multichannel DBS and local-field potential (LFP) recordings. Its performance was verified in a working memory task that involved 4-channel fronto-hippocampal LFP recording and bilateral constant-current fimbria-fornix DBS. The system was synchronised with video-tracking for extraction of LFP at discrete task phases, and DBS was activated intermittently at discrete phases of the task. Main results. In addition to having a fast set-up time, the system could reliably transmit continuous LFP at over 8 hours across 3-5 m distances. During the working memory task, LFP pertaining to discrete task phases was extracted and compared with well-known neural correlates of active exploratory behaviour in rodents. DBS could be wirelessly activated/deactivated at any part of the experiment during EEG recording and transmission, allowing for a seamless integration of this modality. Significance. The wireless system combines a small size with a level of robustness and versatility that can greatly simplify rodent behavioural experiments involving EEG recording and DBS. Designed for versatility and simplicity, the small size and low-cost of the system and its receiver allow for enhanced portability, fast experimental setup times, and pave the way for integration with more complex behaviour.

Viking 1975 Orbiter Development Test Model/Lander Dynamic Test Model dynamic environmental testing - An overview

NASA Technical Reports Server (NTRS)

Milder, G.

1975-01-01

The current work presents an overview of the Viking 1975 environmental testing from an engineering standpoint. An extremely large vibration test fixture had to be designed, analyzed, and integrated into a test setup that employed hydrostatic bearings in a new fashion. A vibration control system was also required that would allow for thirty-six channels of sine-wave peak select control from acceleration, force-of-strain transducers. In addition, some 68 channels of peak limiting shutdown capability were needed for backup and monitoring of other data during the forced vibration test. Pretesting included analyses of the fixture design, overturning moment, control system capabilities, and response of the entire spacecraft/fixture/exciter system to the test environment. Closed-loop control for acoustic testing was a necessity due to the fact that the Viking spacecraft took up a major portion of the volume of the 10,000 cu ft chamber. The spacecraft emerged from testing undamaged.

Application of Controlled Shear Stresses on the Erythrocyte Membrane as a New Approach to Promote Molecule Encapsulation.

PubMed

Casagrande, Giustina; Arienti, Flavio; Mazzocchi, Arabella; Taverna, Francesca; Ravagnani, Fernando; Costantino, MariaLaura

2016-10-01

Human red blood cells (RBCs) have a remarkable capacity to undergo reversible membrane swelling. Resealed erythrocytes have been proposed as carriers and bioreactors to be used in the treatment of various diseases. This work is aimed at developing a setup allowing the encapsulation of test molecules into erythrocytes by inducing reversible pore formation on the RBC membrane through the application of controlled mechanical shear stresses. The designed setup consists of two reservoirs connected by a glass capillary. Each reservoir is connected to a compressor; during the tests, the reservoirs were in turn pressurized to promote erythrocyte flow through the capillary. The setup was filled with a suspension of erythrocytes, phosphate buffer, and FITC-dextran. Dextran was chosen as the diffusive molecule to check membrane pore dimensions. Samples of the suspension were withdrawn at scheduled times while the setup was operating. Flow cytometry and stereo-optical microscopy analyses were used to evaluate the erythrocyte dextran uptake. The setup was shown to be safe, well controlled, and adjustable. The outcomes of the experimental tests showed significant dextran uptake by RBCs up to 8%. Microscopy observations highlighted the formation of echinocytes in the analyzed samples. Erythrocytes from different donors showed different reactions to mechanical stresses. The experimental outcomes proved the possibility to encapsulate test molecules into erythrocytes by applying controlled mechanical shear stresses on the RBC membrane, encouraging further studies. Copyright © 2016 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

Experimental Study of under-platform Damper Kinematics in Presence of Blade Dynamics

NASA Astrophysics Data System (ADS)

Botto, D.; Gastaldi, C.; Gola, M. M.; Umer, M.

2018-01-01

Among the different devices used in the aerospace industries under-platform dampers are widely used in turbo engines to mitigate the blade vibration. Nevertheless, the damper behaviour is not easy to simulate and engineers have been working in order to improve the accuracy with which theoretical contact models predict the damper behaviour. Majority of the experimental setups collect experimental data in terms of blade amplitude reduction which do not increase the knowledge about the damper dynamics and therefore the uncertainty on the damper behaviour remains a big issue. In this paper, a novel test rig has been purposely designed to accommodate a single blade and two under-platform dampers to deeply investigate the damper-blade interactions. In this test bench, a contact force measuring system was designed to extensively measure the damper contact forces. Damper kinematics is rebuilt by using the relative displacement measured between damper and blade. This paper describes the concept behind the new approach, shows the details of new test rig and discusses experimental results by comparing with previously measured results on an old experimental setup.

TH-A-9A-05: Initial Setup Accuracy Comparison Between Frame-Based and Frameless Stereotactic Radiosurgery

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tseng, T; Sheu, R; Todorov, B

2014-06-15

Purpose: To evaluate initial setup accuracy for stereotactic radiosurgery (SRS) between Brainlab frame-based and frameless immobilization system, also to discern the magnitude frameless system has on setup parameters. Methods: The correction shifts from the original setup were compared for total 157 SRS cranial treatments (69 frame-based vs. 88 frameless). All treatments were performed on a Novalis linac with ExacTrac positioning system. Localization box with isocenter overlay was used for initial setup and correction shift was determined by ExacTrac 6D auto-fusion to achieve submillimeter accuracy for treatment. For frameless treatments, mean time interval between simulation and treatment was 5.7 days (rangemore » 0–13). Pearson Chi-Square was used for univariate analysis. Results: The correctional radial shifts (mean±STD, median) for the frame and frameless system measured by ExacTrac were 1.2±1.2mm, 1.1mm and 3.1±3.3mm, 2.0mm, respectively. Treatments with frameless system had a radial shift >2mm more often than those with frames (51.1% vs. 2.9%; p<.0001). To achieve submillimeter accuracy, 85.5% frame-based treatments did not require shift and only 23.9% frameless treatment could succeed with initial setup. There was no statistical significant system offset observed in any direction for either system. For frameless treatments, those treated ≥ 3 days from simulation had statistically higher rates of radial shifts between 1–2mm and >2mm compared to patients treated in a shorter amount of time from simulation (34.3% and 56.7% vs. 28.6% and 33.3%, respectively; p=0.006). Conclusion: Although image-guided positioning system can also achieve submillimeter accuracy for frameless system, users should be cautious regarding the inherent uncertainty of its capability of immobilization. A proper quality assurance procedure for frameless mask manufacturing and a protocol for intra-fraction imaging verification will be crucial for frameless system. Time interval between simulation and treatment was influential to initial setup accuracy. A shorter time frame for frameless SRS treatment could be helpful in minimizing uncertainties in localization.« less

Setup errors and effectiveness of Optical Laser 3D Surface imaging system (Sentinel) in postoperative radiotherapy of breast cancer.

PubMed

Wei, Xiaobo; Liu, Mengjiao; Ding, Yun; Li, Qilin; Cheng, Changhai; Zong, Xian; Yin, Wenming; Chen, Jie; Gu, Wendong

2018-05-08

Breast-conserving surgery (BCS) plus postoperative radiotherapy has become the standard treatment for early-stage breast cancer. The aim of this study was to compare the setup accuracy of optical surface imaging by the Sentinel system with cone-beam computerized tomography (CBCT) imaging currently used in our clinic for patients received BCS. Two optical surface scans were acquired before and immediately after couch movement correction. The correlation between the setup errors as determined by the initial optical surface scan and CBCT was analyzed. The deviation of the second optical surface scan from the reference planning CT was considered an estimate for the residual errors for the new method for patient setup correction. The consequences in terms for necessary planning target volume (PTV) margins for treatment sessions without setup correction applied. We analyzed 145 scans in 27 patients treated for early stage breast cancer. The setup errors of skin marker based patient alignment by optical surface scan and CBCT were correlated, and the residual setup errors as determined by the optical surface scan after couch movement correction were reduced. Optical surface imaging provides a convenient method for improving the setup accuracy for breast cancer patient without unnecessary imaging dose.

A Mock Circulatory System Incorporating a Compliant 3D-Printed Anatomical Model to Investigate Pulmonary Hemodynamics.

PubMed

Knoops, Paul G M; Biglino, Giovanni; Hughes, Alun D; Parker, Kim H; Xu, Linzhang; Schievano, Silvia; Torii, Ryo

2017-07-01

A realistic mock circulatory system (MCS) could be a valuable in vitro testbed to study human circulatory hemodynamics. The objective of this study was to design a MCS replicating the pulmonary arterial circulation, incorporating an anatomically representative arterial model suitable for testing clinically relevant scenarios. A second objective of the study was to ensure the system's compatibility with magnetic resonance imaging (MRI) for additional measurements. A latex pulmonary arterial model with two generations of bifurcations was manufactured starting from a 3D-printed mold reconstructed from patient data. The model was incorporated into a MCS for in vitro hydrodynamic measurements. The setup was tested under physiological pulsatile flow conditions and results were evaluated using wave intensity analysis (WIA) to investigate waves traveling in the arterial system. Increased pulmonary vascular resistance (IPVR) was simulated as an example of one pathological scenario. Flow split between right and left pulmonary artery was found to be realistic (54 and 46%, respectively). No substantial difference in pressure waveform was observed throughout the various generations of bifurcations. Based on WIA, three main waves were identified in the main pulmonary artery (MPA), that is, forward compression wave, backward compression wave, and forward expansion wave. For IPVR, a rise in mean pressure was recorded in the MPA, within the clinical range of pulmonary arterial hypertension. The feasibility of using the MCS in the MRI scanner was demonstrated with the MCS running 2 h consecutively while acquiring preliminary MRI data. This study shows the development and verification of a pulmonary MCS, including an anatomically correct, compliant latex phantom. The setup can be useful to explore a wide range of hemodynamic questions, including the development of patient- and pathology-specific models, considering the ease and low cost of producing rapid prototyping molds, and the versatility of the setup for invasive and noninvasive (i.e., MRI) measurements. © 2016 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

A Mock Circulatory System Incorporating a Compliant 3D-Printed Anatomical Model to Investigate Pulmonary Hemodynamics

PubMed Central

Knoops, Paul G.M.; Biglino, Giovanni; Hughes, Alun D.; Parker, Kim H.; Xu, Linzhang; Schievano, Silvia; Torii, Ryo

2017-01-01

A realistic mock circulatory system (MCS) could be a valuable in vitro testbed to study human circulatory hemodynamics. The objective of this study was to design a MCS replicating the pulmonary arterial circulation, incorporating an anatomically representative arterial model suitable for testing clinically relevant scenarios. A second objective of the study was to ensure the system's compatibility with magnetic resonance imaging (MRI) for additional measurements. A latex pulmonary arterial model with two generations of bifurcations was manufactured starting from a 3D-printed mold reconstructed from patient data. The model was incorporated into a MCS for in vitro hydrodynamic measurements. The setup was tested under physiological pulsatile flow conditions and results were evaluated using wave intensity analysis (WIA) to investigate waves traveling in the arterial system. Increased pulmonary vascular resistance (IPVR) was simulated as an example of one pathological scenario. Flow split between right and left pulmonary artery was found to be realistic (54 and 46%, respectively). No substantial difference in pressure waveform was observed throughout the various generations of bifurcations. Based on WIA, three main waves were identified in the main pulmonary artery (MPA), that is, forward compression wave, backward compression wave, and forward expansion wave. For IPVR, a rise in mean pressure was recorded in the MPA, within the clinical range of pulmonary arterial hypertension. The feasibility of using the MCS in the MRI scanner was demonstrated with the MCS running 2 h consecutively while acquiring preliminary MRI data. This study shows the development and verification of a pulmonary MCS, including an anatomically correct, compliant latex phantom. The setup can be useful to explore a wide range of hemodynamic questions, including the development of patient- and pathology-specific models, considering the ease and low cost of producing rapid prototyping molds, and the versatility of the setup for invasive and noninvasive (i.e., MRI) measurements. PMID:27925228

A new test procedure to evaluate the performance of substations for collective heating systems

NASA Astrophysics Data System (ADS)

Baetens, Robin; Verhaert, Ivan

2017-11-01

The overall heat demand of a single dwelling, existing out of space heating and domestic hot water production, decreases due to higher insulation rates. Because of this, investing in efficient and renewable heat generation becomes less interesting. Therefore, to incorporate renewables or residual heat on a larger scale, district heating or collective heating systems grow in importance. Within this set-up, the substation is responsible for the interaction between local demand for comfort and overall energy performance of the collective heating system. Many different configurations of substations exist, which influence both local comfort and central system performance. Next to that, also hybrids exist with additional local energy input. To evaluate performance of such substations, a new experimental-based test procedure is developed in order to evaluate these different aspects, characterized by the two roles a substation has, namely as heat generator and as heat consumer. The advantage of this approach is that an objective comparison between individual and central systems regarding performance on delivering local comfort can be executed experimentally. The lab set-up consists out of three different subsystems, namely the central system, the domestic hot water consumption and the local space heating. The central system can work with different temperature regimes and control strategies, as these aspects have proven to have the largest influence on actual performance. The domestic hot water system is able to generate similar tap profiles according to eco-design regulation for domestic hot water generation. The space heating system is able to demand a modular heat load.

Clinical experience with a 3D surface patient setup system for alignment of partial-breast irradiation patients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bert, Christoph; Metheany, Katherine G.; Doppke, Karen P.

2006-03-15

Purpose: To assess the utility of surface imaging on patient setup for accelerated partial-breast irradiation (APBI). Methods and Material: A photogrammetry system was used in parallel to APBI setup by laser and portal imaging. Surface data were acquired after laser and port-film setup for 9 patients. Surfaces were analyzed in comparison to a reference surface from the first treatment session by use of rigid transformations. The surface model after laser setup was used in a simulated photogrammetry setup procedure. In addition, breathing data were acquired by surface acquisition at a frame rate of 7 Hz. Results: Mean 3D displacement wasmore » 7.3 mm (SD, 4.4 mm) and 7.6 mm (SD, 4.2 mm) for laser and port film, respectively. Simulated setup with the photogrammetry system yielded mean displacement of 1 mm (SD, 1.2 mm). Distance analysis resulted in mean distances of 3.7 mm (SD, 4.9 mm), 4.3 mm (SD, 5.6 mm), and 1.6 mm (SD, 2.4 mm) for laser, port film, and photogrammetry, respectively. Breathing motion at isocenter was smaller than 3.7 mm, with a mean of 1.9 mm (SD, 1.1 mm). Conclusions: Surface imaging for PBI setup appears promising. Alignment of the 3D breast surface achieved by stereo-photogrammetry shows greater breast topology congruence than when patients are set up by laser or portal imaging. A correlation of breast surface and CTV must be quantitatively established.« less

Six degree of freedom fine motion positioning stage based on magnetic levitation

NASA Technical Reports Server (NTRS)

Arling, R. W.; Kohler, S. M.

1994-01-01

The design of a magnetically suspended six degree of freedom positioning system capable of nanometer positioning is presented. The sample holder is controlled in six degrees of freedom (DOF) over 300 micrometers of travel in the X, Y, and Z directions. A design and control summary and test results indicating stability and power dissipation are included in the paper. The system is vacuum compatible, uses commercially available materials, and requires minimal assembly and setup.

Application of point-diffraction interferometry to testing infrared imaging systems

NASA Astrophysics Data System (ADS)

Smartt, Raymond N.; Paez, Gonzalo

2004-11-01

Point-diffraction interferometry has found wide applications spanning much of the electromagnetic spectrum, including both near- and far-infrared wavelengths. Any telescopic, spectroscopic or other imaging system that converts an incident plane or spherical wavefront into an accessible point-like image can be tested at an intermediate image plane or at the principal image plane, in situ. Angular field performance can be similarly tested with inclined incident wavefronts. Any spatially coherent source can be used, but because of the available flux, it is most convenient to use a laser source. The simplicity of the test setup can allow testing of even large and complex fully-assembled systems. While purely reflective IR systems can be conveniently tested at visible wavelengths (apart from filters), catadioptric systems could be evaluated using an appropriate source and an IRPDI, with an imaging and recording system. PDI operating principles are briefly reviewed, and some more recent developments and interesting applications briefly discussed. Alternative approaches and recommended procedures for testing IR imaging systems, including the thermal IR, are suggested. An example of applying point-diffraction interferometry to testing a relatively low angular-resolution, optically complex IR telescopic system is presented.

Thai National Telescope beam simulator testbed development status

NASA Astrophysics Data System (ADS)

Buisset, Christophe; Prasit, Apirat; Lépine, Thierry; Poshyachinda, Saran; Leckngam, A.

2016-07-01

The Thai National Telescope (TNT) is a Ritchey-Chretien Telescope with a clear aperture ΦM1 = 2.3 m, a focal ratio f/10 and a central obstruction Obsc = 0.3. The TNT is the main instrument of the Thai National Observatory (TNO) which is located near the summit of the Doi Inthanon, situated in the Chiang Mai Province of Thailand at altitude 2,457 meters. The median seeing on this site is approximately 0.9" and is remarkably stable on most nights, rarely exceeding 2". We decided to develop an optical setup to simulate in laboratory conditions the geometry of the TNT output beam. This, in order to carefully prepare and to improve the efficiency of the test to be performed in real conditions at the TNT focal plane level. We specified the setup to be representative of the TNT optical design, beam aperture, central obscuration, geometry of the spider, wavefront quality and PSF size under various seeing conditions. This setup comprises 2 identical Cassegrain telescopes mounted on dedicated supports with 5 degree-of-Freedom. The first application of this setup will be the preparation of the TNT optical alignment. The second application of this setup will be the development and the test of the future instruments for the TNT such as a focal reducer or a spectrograph. In this paper, we discuss the setup specifications we describe the setup optical and mechanical design and we present the performance.

Prediction and validation of the energy dissipation of a friction damper

NASA Astrophysics Data System (ADS)

Lopez, I.; Nijmeijer, H.

2009-12-01

Friction dampers can be a cheap and efficient way to reduce the vibration levels of a wide range of mechanical systems. In the present work it is shown that the maximum energy dissipation and corresponding optimum friction force of friction dampers with stiff localized contacts and large relative displacements within the contact, can be determined with sufficient accuracy using a dry (Coulomb) friction model. Both the numerical calculations with more complex friction models and the experimental results in a laboratory test set-up show that these two quantities are relatively robust properties of a system with friction. The numerical calculations are performed with several friction models currently used in the literature. For the stick phase smooth approximations like viscous damping or the arctan function are considered but also the non-smooth switch friction model is used. For the slip phase several models of the Stribeck effect are used. The test set-up for the laboratory experiments consists of a mass sliding on parallel ball-bearings, where additional friction is created by a sledge attached to the mass, which is pre-stressed against a friction plate. The measured energy dissipation is in good agreement with the theoretical results for Coulomb friction.

Coil-free active stabilisation of extended payloads with optical inertial sensors

NASA Astrophysics Data System (ADS)

Watchi, J.; Ding, B.; Tshilumba, D.; Artoos, K.; Collette, C.

2018-05-01

This paper presents a new active isolation strategy and system which is dedicated to extended payloads, and compatible with the particle accelerator environment. In comparison to the current isolation systems used in this environment, the system proposed does not contain any coil or elastomer, and the supporting frame is dedicated to isolating long payloads from seismic motion. The concept proposed has been tested numerically on 3 and 6 degrees of freedom (DOF) models, and validated experimentally on a 1-DOF scaled test set-up. An attenuation of 40 dB at 1 Hz has been reached with the stage built. The complete description of performance and a noise budgeting are included in this paper.

Performance Evaluation of State of the Art Systems for Physical Activity Classification of Older Subjects Using Inertial Sensors in a Real Life Scenario: A Benchmark Study

PubMed Central

Awais, Muhammad; Palmerini, Luca; Bourke, Alan K.; Ihlen, Espen A. F.; Helbostad, Jorunn L.; Chiari, Lorenzo

2016-01-01

The popularity of using wearable inertial sensors for physical activity classification has dramatically increased in the last decade due to their versatility, low form factor, and low power requirements. Consequently, various systems have been developed to automatically classify daily life activities. However, the scope and implementation of such systems is limited to laboratory-based investigations. Furthermore, these systems are not directly comparable, due to the large diversity in their design (e.g., number of sensors, placement of sensors, data collection environments, data processing techniques, features set, classifiers, cross-validation methods). Hence, the aim of this study is to propose a fair and unbiased benchmark for the field-based validation of three existing systems, highlighting the gap between laboratory and real-life conditions. For this purpose, three representative state-of-the-art systems are chosen and implemented to classify the physical activities of twenty older subjects (76.4 ± 5.6 years). The performance in classifying four basic activities of daily life (sitting, standing, walking, and lying) is analyzed in controlled and free living conditions. To observe the performance of laboratory-based systems in field-based conditions, we trained the activity classification systems using data recorded in a laboratory environment and tested them in real-life conditions in the field. The findings show that the performance of all systems trained with data in the laboratory setting highly deteriorates when tested in real-life conditions, thus highlighting the need to train and test the classification systems in the real-life setting. Moreover, we tested the sensitivity of chosen systems to window size (from 1 s to 10 s) suggesting that overall accuracy decreases with increasing window size. Finally, to evaluate the impact of the number of sensors on the performance, chosen systems are modified considering only the sensing unit worn at the lower back. The results, similarly to the multi-sensor setup, indicate substantial degradation of the performance when laboratory-trained systems are tested in the real-life setting. This degradation is higher than in the multi-sensor setup. Still, the performance provided by the single-sensor approach, when trained and tested with real data, can be acceptable (with an accuracy above 80%). PMID:27973434

Prototype electron lens set-up for the Tevatron beam-beam compensation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crawford, C.; Saewert, G.; Santucci, J.

1999-05-17

A prototype "electron lens" for the Tevatron beam-beam compensation project is commissioned at Fermilab. We de-scribe the set-up, report results of the first tests of the elec-tron beam, and discuss future plans.

KSC-07pd1491

NASA Image and Video Library

2007-06-13

KENNEDY SPACE CENTER, FLA. -- United Space Alliance employees prepared three test articles that will be used in wind tunnel testing by NASA to collect data for analysis of the detached Flexible Insulation Blanket, or FIB, on Atlantis. The test articles each feature three tiles (Low Temperature Reusable Surface Insulation, or LRSI) affixed next to two FIB blankets, simulating the thermal protection system set-up on Atlantis' OMS pod in the vicinity of the in-flight anomaly. These test articles were flown to Texas the morning of June 14. The TPS team at KSC has also provided a total of 22 FIB samples for other testing and analysis. Photo credit: NASA/Kim Shiflett

Wood Bond Testing

NASA Technical Reports Server (NTRS)

1989-01-01

A joint development program between Hartford Steam Boiler Inspection Technologies and The Weyerhaeuser Company resulted in an internal bond analyzer (IBA), a device which combines ultrasonics with acoustic emission testing techniques. It is actually a spinoff from a spinoff, stemming from a NASA Lewis invented acousto-ultrasonic technique that became a system for testing bond strength of composite materials. Hartford's parent company, Acoustic Emission Technology Corporation (AET) refined and commercialized the technology. The IBA builds on the original system and incorporates on-line process control systems. The IBA determines bond strength by measuring changes in pulsar ultrasonic waves injected into a board. Analysis of the wave determines the average internal bond strength for the panel. Results are displayed immediately. Using the system, a mill operator can adjust resin/wood proportion, reduce setup time and waste, produce internal bonds of a consistent quality and automatically mark deficient products.

Neutron Tomography Using Mobile Neutron Generators for Assessment of Void Distributions in Thermal Hydraulic Test Loops

NASA Astrophysics Data System (ADS)

Andersson, P.; Bjelkenstedt, T.; Sundén, E. Andersson; Sjöstrand, H.; Jacobsson-Svärd, S.

Detailed knowledge of the lateral distribution of steam (void) and water in a nuclear fuel assembly is of great value for nuclear reactor operators and fuel manufacturers, with consequences for both reactor safety and economy of operation. Therefore, nuclear relevant two-phase flows are being studied at dedicated thermal-hydraulic test loop, using two-phase flow systems ranging from simplified geometries such as heated circular pipes to full scale mock-ups of nuclear fuel assemblies. Neutron tomography (NT) has been suggested for assessment of the lateral distribution of steam and water in such test loops, motivated by a good ability of neutrons to penetrate the metallic structures of metal pipes and nuclear fuel rod mock-ups, as compared to e.g. conventional X-rays, while the liquid water simultaneously gives comparatively good contrast. However, these stationary test loops require the measurement setup to be mobile, which is often not the case for NT setups. Here, it is acknowledged that fast neutrons of 14 MeV from mobile neutron generators constitute a viable option for a mobile NT system. We present details of the development of neutron tomography for this purpose at the division of Applied Nuclear Physics at Uppsala University. Our concept contains a portable neutron generator, exploiting the fusion reaction of deuterium and tritium, and a detector with plastic scintillator elements designed to achieveadequate spatial and energy resolution, all mounted in a light-weight frame without collimators or bulky moderation to allow for a mobile instrument that can be moved about the stationary thermal hydraulic test sections. The detector system stores event-to-event pulse-height information to allow for discrimination based on the energy deposition in the scintillator elements.

Infrared Video Pupillography Coupled with Smart Phone LED for Measurement of Pupillary Light Reflex.

PubMed

Chang, Lily Yu-Li; Turuwhenua, Jason; Qu, Tian Yuan; Black, Joanna M; Acosta, Monica L

2017-01-01

Clinical assessment of pupil appearance and pupillary light reflex (PLR) may inform us the integrity of the autonomic nervous system (ANS). Current clinical pupil assessment is limited to qualitative examination, and relies on clinical judgment. Infrared (IR) video pupillography combined with image processing software offer the possibility of recording quantitative parameters. In this study we describe an IR video pupillography set-up intended for human and animal testing. As part of the validation, resting pupil diameter was measured in human subjects using the NeurOptics ™ (Irvine, CA, USA) pupillometer, to compare against that measured by our IR video pupillography set-up, and PLR was assessed in guinea pigs. The set-up consisted of a smart phone with a light emitting diode (LED) strobe light (0.2 s light ON, 5 s light OFF cycles) as the stimulus and an IR camera to record pupil kinetics. The consensual response was recorded, and the video recording was processed using a custom MATLAB program. The parameters assessed were resting pupil diameter (D1), constriction velocity (CV), percentage constriction ratio, re-dilation velocity (DV) and percentage re-dilation ratio. We report that the IR video pupillography set-up provided comparable results as the NeurOptics ™ pupillometer in human subjects, and was able to detect larger resting pupil size in juvenile male guinea pigs compared to juvenile female guinea pigs. At juvenile age, male guinea pigs also had stronger pupil kinetics for both pupil constriction and dilation. Furthermore, our IR video pupillography set-up was able to detect an age-specific increase in pupil diameter (female guinea pigs only) and reduction in CV (male and female guinea pigs) as animals developed from juvenile (3 months) to adult age (7 months). This technique demonstrated accurate and quantitative assessment of pupil parameters, and may provide the foundation for further development of an integrated system useful for clinical applications.

An automated psychoacoustic testing apparatus for use in cats.

PubMed

Benovitski, Yuri B; Blamey, Peter J; Rathbone, Graeme D; Fallon, James B

2014-03-01

Animal behavioral studies make a significant contribution to hearing research and provide vital information which is not available from human subjects. Animal psychoacoustics is usually extremely time consuming and labor intensive; in addition, animals may become stressed, especially if restraints or negative reinforcers such as electric shocks are used. We present a novel behavioral experimental system that was developed to allow efficient animal training in response to acoustic stimuli. Cats were required to perform a relatively simple task of moving toward and away from the device depending on whether the members of a tone pair were different or the same in frequency (go/no-go task). The experimental setup proved to be effective, with all animals (N = 7) performing at above 90% correct on an easy task. Animals were trained within 2-4 weeks and then generated a total of 150-200 trials per day, distributed within approximately 8 self initiated sessions. Data collected using this system were stable over 1 week and repeatable over long test periods (14 weeks). Measured frequency discrimination thresholds from 3 animals at 3 different reference frequencies were comparable with previously published results. The main advantages of the system are: relatively simple setup; large amounts of data can be generated without the need of researcher supervision; multiple animals can be tested simultaneously without removal from home pens; and no electric shocks or restraints are required. Copyright © 2013 Elsevier B.V. All rights reserved.

A microprocessor-based table lookup approach for magnetic bearing linearization

NASA Technical Reports Server (NTRS)

Groom, N. J.; Miller, J. B.

1981-01-01

An approach for producing a linear transfer characteristic between force command and force output of a magnetic bearing actuator without flux biasing is presented. The approach is microprocessor based and uses a table lookup to generate drive signals for the magnetic bearing power driver. An experimental test setup used to demonstrate the feasibility of the approach is described, and test results are presented. The test setup contains bearing elements similar to those used in a laboratory model annular momentum control device.

American & Soviet engineers examine ASTP docking set-up following tests

NASA Image and Video Library

1974-07-10

S74-25394 (10 July 1974) --- A group of American and Soviet engineers of the Apollo-Soyuz Test Project working group three examines an ASTP docking set-up following a docking mechanism fitness test conducted in Building 13 at the Johnson Space Center. Working Group No. 3 is concerned with ASTP docking problems and techniques. The joint U.S.-USSR ASTP docking mission in Earth orbit is scheduled for the summer of 1975. The Apollo docking mechanism is atop the Soyuz docking mechanism.

Fast shut-down protection system for radio frequency breakdown and multipactor testing.

PubMed

Graves, T P; Hanson, P; Michaelson, J M; Farkas, A D; Hubble, A A

2014-02-01

Radio frequency (RF) breakdown such as multipactor or ionization breakdown is a device-limiting phenomenon for on-orbit spacecraft used for communication, navigation, or other RF payloads. Ground testing is therefore part of the qualification process for all high power components used in these space systems. This paper illustrates a shut-down protection system to be incorporated into multipactor/ionization breakdown ground testing for susceptible RF devices. This 8 channel system allows simultaneous use of different diagnostic classes and different noise floors. With initiation of a breakdown event, diagnostic signals increase above a user-specified level, which then opens an RF switch to eliminate RF power from the high power amplifier. Examples of this system in use are shown for a typical setup, illustrating the reproducibility of breakdown threshold voltages and the lack of multipactor conditioning. This system can also be utilized to prevent excessive damage to RF components in tests with sensitive or flight hardware.

Hanford Waste End Effector Phase I Test Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Berglin, Eric J.; Hatchell, Brian K.; Mount, Jason C.

This test plan describes the Phase 1 testing program of the Hanford Waste End Effector (HWEE) at the Washington River Protection Solutions’ Cold Test Facility (CTF) using a Pacific Northwest National Laboratory (PNNL)-designed testing setup. This effort fulfills the informational needs for initial assessment of the HWEE to support Hanford single-shell tank A-105 retrieval. This task will install the HWEE on a PNNL-designed robotic gantry system at CTF, install and calibrate instrumentation to measure reaction forces and process parameters, prepare and characterize simulant materials, and implement the test program. The tests will involve retrieval of water, sludge, and hardpan simulantsmore » to determine pumping rate, dilution factors, and screen fouling rate.« less

Six-flow operations for catalyst development in Fischer-Tropsch synthesis: Bridging the gap between high-throughput experimentation and extensive product evaluation

NASA Astrophysics Data System (ADS)

Sartipi, Sina; Jansma, Harrie; Bosma, Duco; Boshuizen, Bart; Makkee, Michiel; Gascon, Jorge; Kapteijn, Freek

2013-12-01

Design and operation of a "six-flow fixed-bed microreactor" setup for Fischer-Tropsch synthesis (FTS) is described. The unit consists of feed and mixing, flow division, reaction, separation, and analysis sections. The reactor system is made of five heating blocks with individual temperature controllers, assuring an identical isothermal zone of at least 10 cm along six fixed-bed microreactor inserts (4 mm inner diameter). Such a lab-scale setup allows running six experiments in parallel, under equal feed composition, reaction temperature, and conditions of separation and analysis equipment. It permits separate collection of wax and liquid samples (from each flow line), allowing operation with high productivities of C5+ hydrocarbons. The latter is crucial for a complete understanding of FTS product compositions and will represent an advantage over high-throughput setups with more than ten flows where such instrumental considerations lead to elevated equipment volume, cost, and operation complexity. The identical performance (of the six flows) under similar reaction conditions was assured by testing a same catalyst batch, loaded in all microreactors.

Design of a continuous process setup for precipitated calcium carbonate production from steel converter slag.

PubMed

Mattila, Hannu-Petteri; Zevenhoven, Ron

2014-03-01

A mineral carbonation process "slag2PCC" for carbon capture, utilization, and storage is discussed. Ca is extracted from steel slag by an ammonium salt solvent and carbonated with gaseous CO2 after the separation of the residual slag. The solvent is reused after regeneration. The effects of slag properties such as the content of free lime, fractions of Ca, Si, Fe, and V, particle size, and slag storage on the Ca extraction efficiency are studied. Small particles with a high free-lime content and minor fractions of Si and V are the most suitable. To limit the amount of impurities in the process, the slag-to-liquid ratio should remain below a certain value, which depends on the slag composition. Also, the design of a continuous test setup (total volume ∼75 L) is described, which enables quick process variations needed to adapt the system to the varying slag quality. Different precipitated calcium carbonate crystals (calcite and vaterite) are generated in different parts of the setup. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Chromophore Poling in Thin Films of Organic Glasses. 2. Two-Electrode Corona Discharge Setup

NASA Astrophysics Data System (ADS)

Vilitis, O.; Muzikante, I.; Rutkis, M.; Vembris, A.

2012-01-01

In Part 1 of the article we provided description of the corona discharge physics and overview of the methods used for corona poling in thin organic films. Subsequent sections describe comparatively simple technical methods for poling the organic nonlinear optical polymers using a two-electrode (point-to-plate or wire-to-plate) technique. The polarization build-up was studied by the DC positive corona method for poling the nonlinear optical (NLO) polymers. The experimental setup provides the corona discharge current from 0.5 μA up to 3 μA by applying 3 kV - 12 kV voltage to the corona electrode and makes possible selection among the types of corona electrodes (needle, multi-needle, wire, etc.). The results of experimental testing of the poling setup show that at fixed optimal operational parameters of poling - the sample orientation temperature and the discharge current - the corona charging of polymeric materials can successfully be performed applying the two-electrode technique. To study the dynamics of both poling and charge transport processes the three-electrode charging system - a corona triode - should be applied.

Implementation of the Timepix ASIC in the Scalable Readout System

NASA Astrophysics Data System (ADS)

Lupberger, M.; Desch, K.; Kaminski, J.

2016-09-01

We report on the development of electronics hardware, FPGA firmware and software to provide a flexible multi-chip readout of the Timepix ASIC within the framework of the Scalable Readout System (SRS). The system features FPGA-based zero-suppression and the possibility to read out up to 4×8 chips with a single Front End Concentrator (FEC). By operating several FECs in parallel, in principle an arbitrary number of chips can be read out, exploiting the scaling features of SRS. Specifically, we tested the system with a setup consisting of 160 Timepix ASICs, operated as GridPix devices in a large TPC field cage in a 1 T magnetic field at a DESY test beam facility providing an electron beam of up to 6 GeV. We discuss the design choices, the dedicated hardware components, the FPGA firmware as well as the performance of the system in the test beam.

New education system for construction of optical holography setup - Tangible learning with Augmented Reality

NASA Astrophysics Data System (ADS)

Yamaguchi, Takeshi; Yoshikawa, Hiroshi

2013-02-01

In case of teaching optical system construction, it is difficult to prepare the optical components for the attendance student. However the tangible learning is very important to master the optical system construction. It helps learners understand easily to use an inexpensive learning system that provides optical experiments experiences. Therefore, we propose the new education system for construction of optical setup with the augmented reality. To use the augmented reality, the proposed system can simulate the optical system construction by the direct hand control. Also, this system only requires an inexpensive web camera, printed makers and a personal computer. Since this system does not require the darkroom and the expensive optical equipments, the learners can study anytime, anywhere when they want to do. In this paper, we developed the system that can teach the optical system construction of the Denisyuk hologram and 2-step transmission type hologram. For the tangible learning and the easy understanding, the proposed system displays the CG objects of the optical components on the markers which are controlled by the learner's hands. The proposed system does not only display the CG object, but also display the light beam which is controlled by the optical components. To display the light beam that is hard to be seen directly, the learners can confirm about what is happening by the own manipulation. For the construction of optical holography setup, we arrange a laser, mirrors, a PBS (polarizing beam splitter), lenses, a polarizer, half-wave plates, spatial filters, an optical power meter and a recording plate. After the construction, proposed system can check optical setup correctly. In comparison with the learners who only read a book, the learners who use the system can construct the optical holography setup more quickly and correctly.

Kelly takes photo of BCAT-5 Payload Setup

NASA Image and Video Library

2011-02-23

ISS026-E-028666 (23 Feb. 2011) --- NASA astronaut Scott Kelly, Expedition 26 commander, uses a digital still camera to photograph the Binary Colloidal Alloy Test-5 (BCAT-5) payload setup in the Kibo laboratory of the International Space Station.

Estimating Setup of Driven Piles into Louisiana Clayey Soils

DOT National Transportation Integrated Search

2009-11-15

Two types of mathematical models for pile setup prediction, the Skov-Denver model and the newly developed rate-based model, have been established from all the dynamic and static testing data, including restrikes of the production piles, restrikes, st...

Estimating setup of driven piles into Louisiana clayey soils.

DOT National Transportation Integrated Search

2010-11-15

Two types of mathematical models for pile setup prediction, the Skov-Denver model and the newly developed rate-based model, have been established from all the dynamic and static testing data, including restrikes of the production piles, restrikes, st...

Comparison of two types of neonatal extracorporeal life support systems with pulsatile and nonpulsatile flow.

PubMed

Haines, Nikkole; Wang, Shigang; Myers, John L; Undar, Akif

2009-11-01

We compared the effects of two neonatal extracorporeal life support (ECLS) systems on circuit pressures and surplus hemodynamic energy levels in a simulated ECLS model. The clinical set-up included the Jostra HL-20 heart-lung machine, either the Medtronic ECMO (0800) or the MEDOS 800LT systems with company-provided circuit components, a 10 Fr arterial cannula, and a pseudo-patient. We tested the system in nonpulsatile and pulsatile flow modes at two flow rates using a 40/60 glycerin/water blood analog, for a total of 48 trials, with n = 6 for each set-up. The pressure drops over the Medtronic ECLS were significantly higher than those over the MEDOS system regardless of the flow rate or perfusion mode (144.8 +/- 0.2 mm Hg vs. 35.7 +/- 0.2 mm Hg, respectively, at 500 mL/min in nonpulsatile mode, P < 0.001). The preoxygenator mean arterial pressures were significantly increased and the precannula hemodynamic energy values were decreased with the Medtronic ECLS circuit. These results suggest that the MEDOS ECLS circuit better transmits hemodynamic energy to the patient, keeps mean circuit pressures lower, and has lower pressure drops than the Medtronic Circuit.

Use of an AC induction motor system for producing finger movements in human subjects.

PubMed

Proudlock, F A; Scott, J J

1998-12-01

This report describes the set-up and evaluation of a novel system for producing precise finger movements, for tests of movement perception. The specifications were to construct a system using commercially available components that were easy to use but which offered both flexibility and also high precision control. The system was constructed around an industrial AC induction motor with an optical encoder, controlled by an AC servo digital control module that could be programmed using a simple, high-level language. This set-up fulfilled the requirements regarding position and velocity control for a range of movements and also the facility for the subject to move the joint voluntarily while still attached to the motor. However a number of problems were encountered, the most serious being the level of vibration and the inability to vary the torque during movements. The vibration was reduced to the point where it did not affect the subject, by the introduction of mechanical dampening using an anti-vibration coupling and a pneumatic splint. The torque control could not be modified during rotation and so the system could only be operated using constant torque for any given movement.

Beam Loss Monitoring for LHC Machine Protection

NASA Astrophysics Data System (ADS)

Holzer, Eva Barbara; Dehning, Bernd; Effnger, Ewald; Emery, Jonathan; Grishin, Viatcheslav; Hajdu, Csaba; Jackson, Stephen; Kurfuerst, Christoph; Marsili, Aurelien; Misiowiec, Marek; Nagel, Markus; Busto, Eduardo Nebot Del; Nordt, Annika; Roderick, Chris; Sapinski, Mariusz; Zamantzas, Christos

The energy stored in the nominal LHC beams is two times 362 MJ, 100 times the energy of the Tevatron. As little as 1 mJ/cm3 deposited energy quenches a magnet at 7 TeV and 1 J/cm3 causes magnet damage. The beam dumps are the only places to safely dispose of this beam. One of the key systems for machine protection is the beam loss monitoring (BLM) system. About 3600 ionization chambers are installed at likely or critical loss locations around the LHC ring. The losses are integrated in 12 time intervals ranging from 40 μs to 84 s and compared to threshold values defined in 32 energy ranges. A beam abort is requested when potentially dangerous losses are detected or when any of the numerous internal system validation tests fails. In addition, loss data are used for machine set-up and operational verifications. The collimation system for example uses the loss data for set-up and regular performance verification. Commissioning and operational experience of the BLM are presented: The machine protection functionality of the BLM system has been fully reliable; the LHC availability has not been compromised by false beam aborts.

Method for measurement of radon diffusion and solubility in solid materials

NASA Astrophysics Data System (ADS)

Maier, Andreas; Weber, Uli; Dickmann, Jannis; Breckow, Joachim; van Beek, Patrick; Schardt, Dieter; Kraft, Gerhard; Fournier, Claudia

2018-02-01

In order to study the permeation i.e. the diffusion and solubility of radon gas in biological material, a new setup was constructed and a novel analysis was applied to obtain diffusion and solubility coefficients. Thin slabs of solid materials were installed between detector housing and the surrounding radon exposure chamber of 50 Ls volume. In this setup radon can diffuse through thin test samples into a cylindrical volume of 5 mm height and 20 mm diameter and reach an α-particle detector. There the 5.49 MeV α-decay of the penetrating radon atoms is measured by a silicon surface barrier detector. The time dependent activities inside the small detector volume are recorded after injection of a known radon activity concentration into the outer chamber. Analyzing the time behavior of the integral α-activity from radon in the small vessel, both, the diffusion coefficient and solubility of the test material can be determined, based on a new mathematical model of the diffusion process concerning the special boundary conditions given by the experimental setup. These first measurements were intended as proof of concept for the detection system and the data analysis. Thin polyethylene foils (LDPE) were selected as material for the diffusion measurements and the results were in agreement with data from literature. In further measurements, we will concentrate on biological material like bone, fat and other tissues.

Chapter 51: How to Build a Simple Cone Search Service Using a Local Database

NASA Astrophysics Data System (ADS)

Kent, B. R.; Greene, G. R.

The cone search service protocol will be examined from the server side in this chapter. A simple cone search service will be setup and configured locally using MySQL. Data will be read into a table, and the Java JDBC will be used to connect to the database. Readers will understand the VO cone search specification and how to use it to query a database on their local systems and return an XML/VOTable file based on an input of RA/DEC coordinates and a search radius. The cone search in this example will be deployed as a Java servlet. The resulting cone search can be tested with a verification service. This basic setup can be used with other languages and relational databases.

A programmable closed-loop recording and stimulating wireless system for behaving small laboratory animals

PubMed Central

Angotzi, Gian Nicola; Boi, Fabio; Zordan, Stefano; Bonfanti, Andrea; Vato, Alessandro

2014-01-01

A portable 16-channels microcontroller-based wireless system for a bi-directional interaction with the central nervous system is presented in this work. The device is designed to be used with freely behaving small laboratory animals and allows recording of spontaneous and evoked neural activity wirelessly transmitted and stored on a personal computer. Biphasic current stimuli with programmable duration, frequency and amplitude may be triggered in real-time on the basis of the recorded neural activity as well as by the animal behavior within a specifically designed experimental setup. An intuitive graphical user interface was developed to configure and to monitor the whole system. The system was successfully tested through bench tests and in vivo measurements on behaving rats chronically implanted with multi-channels microwire arrays. PMID:25096831

Test development for the thermionic system evaluation test (TSET) project

NASA Astrophysics Data System (ADS)

Morris, D. Brent; Standley, Vaughn H.; Schuller, Michael J.

1992-01-01

The arrival of a Soviet TOPAZ-II space nuclear reactor affords the US space nuclear power (SNP) community the opportunity to study an assembled thermionic conversion power system. The TOPAZ-II will be studied via the Thermionic System Evaluation Test (TSET) Project. This paper is devoted to the discussion of TSET test development as related to the objectives contained in the TSET Project Plan (Standley et al. 1991). The objectives contained in the Project Plan are the foundation for scheduled TSET tests on TOPAZ-II and are derived from the needs of the Air Force Thermionic SNP program. Our ability to meet the objectives is bounded by unique constraints, such as procurement requirements, operational limitations, and necessary interaction between US and Soviet Scientists and engineers. The fulfillment of the test objectives involves a thorough methodology of test scheduling and data managment. The overall goals for the TSET program are gaining technical understanding of a thermionic SNP system and demonstrating the capabilities and limitations of such a system while assisting in the training of US scientist and engineers in preparation for US SNP system testing. Tests presently scheduled as part of TSET include setup, demonstration, and verification tests; normal and off-normal operating test, and system and component performance tests.

THz QCL-based active imaging dedicated to non-destructive testing of composite materials used in aeronautics

NASA Astrophysics Data System (ADS)

Destic, F.; Petitjean, Y.; Massenot, S.; Mollier, J.-C.; Barbieri, S.

2010-08-01

This paper presents a CW raster-scanning THz imaging setup, used to perform Non-Destructive Testing of KevlarTMand carbon fibre samples. The setup uses a 2.5 THz Quantum Cascade Laser as a source. Delamination defect in a Kevlar sample was detected showing a sensitivity to laser polarization orientation. Detection of a break in a carbon/epoxy sample was also performed.

NREL and SDG&E Collaboration to Support SDG&E Grid and Storage Efforts: Cooperative Research and Development Final Report, CRADA Number CRD-14-562

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baggu, Murali

2017-01-01

This project will enable effective utilization of high penetration of photovoltaics (PV) in islanded microgrids, increasing overall system efficiency, decreased fuel costs and resiliency of the overall system to help meet the SunShot goals of enhancing system integration methods to increase penetration of PV. National Renewable Energy Laboratory (NREL) will collaborate with San Diego Gas & Electric (SDG&E) to provide research and testing support to address their needs in energy storage sizing and placement, Integrated Test Facility (ITF) development, Real Time Digital Simulator (RTDS) Modeling and simulation support at ITF, Visualization and Virtual connection to Energy Systems Integration Facility (ESIF),more » and microgrid simulation and testing areas. Specifically in this project a real microgrid scenario with high penetration of PV (existing in SDG&E territory) is tested in the ESIF laboratory. Multiple control cases for firming PV using storage in a microgrid scenario will be investigated and tested in the laboratory setup.« less

Current-limiting and ultrafast system for the characterization of resistive random access memories.

PubMed

Diaz-Fortuny, J; Maestro, M; Martin-Martinez, J; Crespo-Yepes, A; Rodriguez, R; Nafria, M; Aymerich, X

2016-06-01

A new system for the ultrafast characterization of resistive switching phenomenon is developed to acquire the current during the Set and Reset process in a microsecond time scale. A new electronic circuit has been developed as a part of the main setup system, which is capable of (i) applying a hardware current limit ranging from nanoampers up to miliampers and (ii) converting the Set and Reset exponential gate current range into an equivalent linear voltage. The complete system setup allows measuring with a microsecond resolution. Some examples demonstrate that, with the developed setup, an in-depth analysis of resistive switching phenomenon and random telegraph noise can be made.

Coleman takes photo of BCAT-5 Payload Setup

NASA Image and Video Library

2011-02-23

ISS026-E-028660 (23 Feb. 2011) --- NASA astronaut Catherine (Cady) Coleman, Expedition 26 flight engineer, uses a digital still camera to photograph the Binary Colloidal Alloy Test-5 (BCAT-5) payload setup in the Kibo laboratory of the International Space Station.

SU-E-J-88: The Study of Setup Error Measured by CBCT in Postoperative Radiotherapy for Cervical Carcinoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Runxiao, L; Aikun, W; Xiaomei, F

2015-06-15

Purpose: To compare two registration methods in the CBCT guided radiotherapy for cervical carcinoma, analyze the setup errors and registration methods, determine the margin required for clinical target volume(CTV) extending to planning target volume(PTV). Methods: Twenty patients with cervical carcinoma were enrolled. All patients were underwent CT simulation in the supine position. Transfering the CT images to the treatment planning system and defining the CTV, PTV and the organs at risk (OAR), then transmit them to the XVI workshop. CBCT scans were performed before radiotherapy and registered to planning CT images according to bone and gray value registration methods. Comparedmore » two methods and obtain left-right(X), superior-inferior(Y), anterior-posterior (Z) setup errors, the margin required for CTV to PTV were calculated. Results: Setup errors were unavoidable in postoperative cervical carcinoma irradiation. The setup errors measured by method of bone (systemic ± random) on X(1eft.right),Y(superior.inferior),Z(anterior.posterior) directions were(0.24±3.62),(0.77±5.05) and (0.13±3.89)mm, respectively, the setup errors measured by method of grey (systemic ± random) on X(1eft-right), Y(superior-inferior), Z(anterior-posterior) directions were(0.31±3.93), (0.85±5.16) and (0.21±4.12)mm, respectively.The spatial distributions of setup error was maximum in Y direction. The margins were 4 mm in X axis, 6 mm in Y axis, 4 mm in Z axis respectively.These two registration methods were similar and highly recommended. Conclusion: Both bone and grey registration methods could offer an accurate setup error. The influence of setup errors of a PTV margin would be suggested by 4mm, 4mm and 6mm on X, Y and Z directions for postoperative radiotherapy for cervical carcinoma.« less

From phase drift to synchronisation - pedestrian stepping behaviour on laterally oscillating structures and consequences for dynamic stability

NASA Astrophysics Data System (ADS)

Bocian, Mateusz; Burn, Jeremy F.; Macdonald, John H. G.; Brownjohn, James M. W.

2017-03-01

The subject of this paper pertains to the contentious issue of synchronisation of walking pedestrians to lateral structural motion, which is the mechanism most commonly purported to cause lateral dynamic instability. Tests have been conducted on a custom-built experimental setup consisting of an instrumented treadmill laterally driven by a hydraulic shaking table. The experimental setup can accommodate adaptive pedestrian behaviour via a bespoke speed feedback control mechanism that allows automatic adjustment of the treadmill belt speed to that of the walker. 15 people participated in a total of 137 walking tests during which the treadmill underwent lateral sinusoidal motion. The amplitude of this motion was set from 5 to 15 mm and the frequency was set from 0.54 to 1.1 Hz. A variety of stepping behaviours are identified in the kinematic data obtained using a motion capture system. The most common behaviour is for the timing of footsteps to be essentially unaffected by the structural motion, but a few instances of synchronisation are found. A plausible mechanism comprising an intermediate state between unsynchronised and synchronised pedestrian and structural motion is observed. This mechanism, characterised by a weak form of modulation of the timing of footsteps, could possibly explain the under-estimation of negative damping coefficients in models and laboratory trials compared with previously reported site measurements. The results from tests conducted on the setup for which synchronisation is identified are evaluated in the context of structural stability and related to the predictions of the inverted pendulum model, providing insight into fundamental relations governing pedestrian behaviour on laterally oscillating structures.

Halbach Magnetic Rotor Development

NASA Technical Reports Server (NTRS)

Gallo, Christopher A.

2008-01-01

The NASA John H. Glenn Research Center has a wealth of experience in Halbach array technology through the Fundamental Aeronautics Program. The goals of the program include improving aircraft efficiency, reliability, and safety. The concept of a Halbach magnetically levitated electric aircraft motor will help reduce harmful emissions, reduce the Nation s dependence on fossil fuels, increase efficiency and reliability, reduce maintenance and decrease operating noise levels. Experimental hardware systems were developed in the GRC Engineering Development Division to validate the basic principles described herein and the theoretical work that was performed. A number of Halbach Magnetic rotors have been developed and tested under this program. A separate test hardware setup was developed to characterize each of the rotors. A second hardware setup was developed to test the levitation characteristics of the rotors. Each system focused around a unique Halbach array rotor. Each rotor required original design and fabrication techniques. A 4 in. diameter rotor was developed to test the radial levitation effects for use as a magnetic bearing. To show scalability from the 4 in. rotor, a 1 in. rotor was developed to also test radial levitation effects. The next rotor to be developed was 20 in. in diameter again to show scalability from the 4 in. rotor. An axial rotor was developed to determine the force that could be generated to position the rotor axially while it is rotating. With both radial and axial magnetic bearings, the rotor would be completely suspended magnetically. The purpose of this report is to document the development of a series of Halbach magnetic rotors to be used in testing. The design, fabrication and assembly of the rotors will be discussed as well as the hardware developed to test the rotors.

The use of emulator-based simulators for on-board software maintenance

NASA Astrophysics Data System (ADS)

Irvine, M. M.; Dartnell, A.

2002-07-01

Traditionally, onboard software maintenance activities within the space sector are performed using hardware-based facilities. These facilities are developed around the use of hardware emulation or breadboards containing target processors. Some sort of environment is provided around the hardware to support the maintenance actives. However, these environments are not easy to use to set-up the required test scenarios, particularly when the onboard software executes in a dynamic I/O environment, e.g. attitude control software, or data handling software. In addition, the hardware and/or environment may not support the test set-up required during investigations into software anomalies, e.g. raise spurious interrupt, fail memory, etc, and the overall "visibility" of the software executing may be limited. The Software Maintenance Simulator (SOMSIM) is a tool that can support the traditional maintenance facilities. The following list contains some of the main benefits that SOMSIM can provide: Low cost flexible extension to existing product - operational simulator containing software processor emulator; System-level high-fidelity test-bed in which software "executes"; Provides a high degree of control/configuration over the entire "system", including contingency conditions perhaps not possible with real hardware; High visibility and control over execution of emulated software. This paper describes the SOMSIM concept in more detail, and also describes the SOMSIM study being carried out for ESA/ESOC by VEGA IT GmbH.

The impact of wind energy turbine piles on ocean dynamics

NASA Astrophysics Data System (ADS)

Grashorn, Sebastian; Stanev, Emil V.

2016-04-01

The small- and meso-scale ocean response to wind parks has not been investigated in the southern North Sea until now with the help of high-resolution numerical modelling. Obstacles such as e.g. wind turbine piles may influence the ocean current system and produce turbulent kinetic energy which could affect sediment dynamics in the surrounding area. Two setups of the unstructured-grid model SCHISM (Semi-implicit Cross-scale Hydroscience Integrated System Model) have been developed for an idealized channel including a surface piercing cylindrical obstacle representing the pile and a more realistic test case including four exemplary piles. Experiments using a constant flow around the obstacles and a rotating M2 tidal wave are carried out. The resulting current and turbulence patterns are investigated to estimate the influence of the obstacles on the surrounding ocean dynamics. We demonstrate that using an unstructured ocean model provides the opportunity to embed a high-resolution representation of a wind park turbine pile system into a coarser North Sea setup, which is needed in order to perform a seamless investigation of the resulting geophysical processes.

Quality assurance for kilo- and megavoltage in-room imaging and localization for off- and online setup error correction.

PubMed

Balter, James M; Antonuk, Larry E

2008-01-01

In-room radiography is not a new concept for image-guided radiation therapy. Rapid advances in technology, however, have made this positioning method convenient, and thus radiograph-based positioning has propagated widely. The paradigms for quality assurance of radiograph-based positioning include imager performance, systems integration, infrastructure, procedure documentation and testing, and support for positioning strategy implementation.

Analytical gradients for subsystem density functional theory within the slater-function-based amsterdam density functional program.

PubMed

Schlüns, Danny; Franchini, Mirko; Götz, Andreas W; Neugebauer, Johannes; Jacob, Christoph R; Visscher, Lucas

2017-02-05

We present a new implementation of analytical gradients for subsystem density-functional theory (sDFT) and frozen-density embedding (FDE) into the Amsterdam Density Functional program (ADF). The underlying theory and necessary expressions for the implementation are derived and discussed in detail for various FDE and sDFT setups. The parallel implementation is numerically verified and geometry optimizations with different functional combinations (LDA/TF and PW91/PW91K) are conducted and compared to reference data. Our results confirm that sDFT-LDA/TF yields good equilibrium distances for the systems studied here (mean absolute deviation: 0.09 Å) compared to reference wave-function theory results. However, sDFT-PW91/PW91k quite consistently yields smaller equilibrium distances (mean absolute deviation: 0.23 Å). The flexibility of our new implementation is demonstrated for an HCN-trimer test system, for which several different setups are applied. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Single ion hit detection set-up for the Zagreb ion microprobe

NASA Astrophysics Data System (ADS)

Smith, R. W.; Karlušić, M.; Jakšić, M.

2012-04-01

Irradiation of materials by heavy ions accelerated in MV tandem accelerators may lead to the production of latent ion tracks in many insulators and semiconductors. If irradiation is performed in a high resolution microprobe facility, ion tracks can be ordered by submicrometer positioning precision. However, full control of the ion track positioning can only be achieved by a reliable ion hit detection system that should provide a trigger signal irrespectively of the type and thickness of the material being irradiated. The most useful process that can be utilised for this purpose is emission of secondary electrons from the sample surface that follows the ion impact. The status report of the set-up presented here is based on the use of a channel electron multiplier (CEM) detector mounted on an interchangable sample holder that is inserted into the chamber in a close geometry along with the sample to be irradiated. The set-up has been tested at the Zagreb ion microprobe for different ions and energies, as well as different geometrical arrangements. For energies of heavy ions below 1 MeV/amu, results show that efficient (100%) control of ion impact can be achieved only for ions heavier than silicon. The successful use of the set-up is demonstrated by production of ordered single ion tracks in a polycarbonate film and by monitoring fluence during ion microbeam patterning of Foturan glass.

Surgical robot setup simulation with consistent kinematics and haptics for abdominal surgery.

PubMed

Hayashibe, Mitsuhiro; Suzuki, Naoki; Hattori, Asaki; Suzuki, Shigeyuki; Konishi, Kozo; Kakeji, Yoshihiro; Hashizume, Makoto

2005-01-01

Preoperative simulation and planning of surgical robot setup should accompany advanced robotic surgery if their advantages are to be further pursued. Feedback from the planning system will plays an essential role in computer-aided robotic surgery in addition to preoperative detailed geometric information from patient CT/MRI images. Surgical robot setup simulation systems for appropriate trocar site placement have been developed especially for abdominal surgery. The motion of the surgical robot can be simulated and rehearsed with kinematic constraints at the trocar site, and the inverse-kinematics of the robot. Results from simulation using clinical patient data verify the effectiveness of the proposed system.

Model-based setup assistant for progressive tools

NASA Astrophysics Data System (ADS)

Springer, Robert; Gräler, Manuel; Homberg, Werner; Henke, Christian; Trächtler, Ansgar

2018-05-01

In the field of production systems, globalization and technological progress lead to increasing requirements regarding part quality, delivery time and costs. Hence, today's production is challenged much more than a few years ago: it has to be very flexible and produce economically small batch sizes to satisfy consumer's demands and avoid unnecessary stock. Furthermore, a trend towards increasing functional integration continues to lead to an ongoing miniaturization of sheet metal components. In the industry of electric connectivity for example, the miniaturized connectors are manufactured by progressive tools, which are usually used for very large batches. These tools are installed in mechanical presses and then set up by a technician, who has to manually adjust a wide range of punch-bending operations. Disturbances like material thickness, temperatures, lubrication or tool wear complicate the setup procedure. In prospect of the increasing demand of production flexibility, this time-consuming process has to be handled more and more often. In this paper, a new approach for a model-based setup assistant is proposed as a solution, which is exemplarily applied in combination with a progressive tool. First, progressive tools, more specifically, their setup process is described and based on that, the challenges are pointed out. As a result, a systematic process to set up the machines is introduced. Following, the process is investigated with an FE-Analysis regarding the effects of the disturbances. In the next step, design of experiments is used to systematically develop a regression model of the system's behaviour. This model is integrated within an optimization in order to calculate optimal machine parameters and the following necessary adjustment of the progressive tool due to the disturbances. Finally, the assistant is tested in a production environment and the results are discussed.

Communication Satellite Payload Special Check out Equipment (SCOE) for Satellite Testing

NASA Astrophysics Data System (ADS)

Subhani, Noman

2016-07-01

This paper presents Payload Special Check out Equipment (SCOE) for the test and measurement of communication satellite Payload at subsystem and system level. The main emphasis of this paper is to demonstrate the principle test equipment, instruments and the payload test matrix for an automatic test control. Electrical Ground Support Equipment (EGSE)/ Special Check out Equipment (SCOE) requirements, functions and architecture for C-band and Ku-band payloads are presented in details along with their interface with satellite during different phases of satellite testing. It provides test setup, in a single rack cabinet that can easily be moved from payload assembly and integration environment to thermal vacuum chamber all the way to launch site (for pre-launch test and verification).

More on Faraday's and Lenz's laws - Qualitative demonstrations

NASA Astrophysics Data System (ADS)

Hessel, Roberto

2011-03-01

A large variety of simple setups for demonstrating Faraday's and Lenz's laws have been described in the literature.1-4 For a few semesters, we tested some of these setups, especially those suggested in Ref. 1, but recently we decided to develop our own version.

The KUT meteor radar: An educational low cost meteor observation system by radio forward scattering

NASA Astrophysics Data System (ADS)

Madkour, W.; Yamamoto, M.

2016-01-01

The Kochi University of Technology (KUT) meteor radar is an educational low cost observation system built at Kochi, Japan by successive graduate students since 2004. The system takes advantage of the continuous VHF- band beacon signal emitted from Fukui National College of Technology (FNCT) for scientific usage all over Japan by receiving the forward scattered signals. The system uses the classical forward scattering setup similar to the setup described by the international meteor organization (IMO), gradually developed from the most basic single antenna setup to the multi-site meteor path determination setup. The primary objective is to automate the observation of the meteor parameters continuously to provide amounts of data sufficient for statistical analysis. The developed software system automates the observation of the astronomical meteor parameters such as meteor direction, velocity and trajectory. Also, automated counting of meteor echoes and their durations are used to observe mesospheric ozone concentration by analyzing the duration distribution of different meteor showers. The meteor parameters observed and the methodology used for each are briefly summarized.

In-air RBS measurements at the LAMFI external beam setup

DOE Office of Scientific and Technical Information (OSTI.GOV)

Silva, T. F.; Added, N.; Moro, M. V.

2014-11-11

This work describes new developments in the external beam setup of the Laboratory of Material Analysis with Ion Beams of the University of São Paulo (LAMFI-USP). This setup was designed to be a versatile analytical station to analyze a broad range of samples. In recent developments, we seek the external beam Rutherford Backscattering Spectroscopy (RBS) analysis to complement the Particle Induced X-ray Emission (PIXE) measurements. This work presents the initial results of the external beam RBS analysis as well as recent developments to improve the energy resolution RBS measurements, in particular tests to seek for sources of resolution degradation. Thesemore » aspects are discussed and preliminary results of in-air RBS analysis of some test samples are presented.« less

Development of a gas-pressurized high-pressure μSR setup at the RIKEN-RAL Muon Facility

NASA Astrophysics Data System (ADS)

Watanabe, I.; Ishii, Y.; Kawamata, T.; Suzuki, T.; Pratt, F. L.; Done, R.; Chowdhury, M.; Goodway, C.; Dreyer, J.; Smith, C.; Southern, M.

2009-04-01

The development and testing of a gas-pressurized μSR setup for the RIKEN-RAL Muon Facility is reported. In collaboration with the high-pressure group of the ISIS Facility at the Rutherford Appleton Laboratory, a gas-pressurized setup for a pulsed muon beam at the RIKEN-RAL Muon Facility has been constructed in 2008. The sample is pressurized by helium gas and the designed maximum pressure is 6.4 kbar. The high-pressure cell can be cooled down to 2 K using an existing cryostat. Tests were made injecting the double-pulsed muon beam into a high-purity sample of Sn powder, which confirmed that the maximum pressure achieved at 2 K was close to the designed pressure.

Measurement and analysis of chatter in a compliant model of a drillstring equipped with a PDC bit

DOE Office of Scientific and Technical Information (OSTI.GOV)

Elsayed, M.A.; Raymond, D.W.

1999-11-09

Typical laboratory testing of Polycrystalline Diamond Compact (PDC) bits is performed on relatively rigid setups. Even in hard rock, PDC bits exhibit reasonable life using such testing schemes. Unfortunately, field experience indicates otherwise. In this paper, the authors show that introducing compliance in testing setups provides better simulation of actual field conditions. Using such a scheme, they show that chatter can be severe even in softer rock, such as sandstone, and very destructive to the cutters in hard rock, such as sierra white granite.

Evaluation of Thermal Protection Tile Transmissibility for Ground Vibration Test

NASA Technical Reports Server (NTRS)

Chung, Y. T.; Fowler, Samuel B.; Lo, Wenso; Towner, Robert

2005-01-01

Transmissibility analyses and tests were conducted on a composite panel with thermal protection system foams to evaluate the quality of the measured frequency response functions. Both the analysis and the test results indicate that the vehicle dynamic responses are fully transmitted to the accelerometers mounted on the thermal protection system in the normal direction below a certain frequency. In addition, the in-plane motions of the accelerometer mounted on the top surface of the thermal protection system behave more actively than those on the composite panel due to the geometric offset of the accelerometer from the panel in the test set-up. The transmissibility tests and analyses show that the frequency response functions measured from the accelerometers mounted on the TPS will provide accurate vehicle responses below 120 Hz for frequency and mode shape identification. By confirming that accurate dynamic responses below a given frequency can be obtained, this study increases the confidence needed for conducting the modal testing, model correlation, and model updating for a vehicle installed with TPS. '

Test and Analysis of a Hyper-X Carbon-Carbon Leading Edge Chine

NASA Technical Reports Server (NTRS)

Smith, Russell W.; Sikora, Joseph G.; Lindell, Michael C.

2005-01-01

During parts production for the X43A Mach 10 hypersonic vehicle nondestructive evaluation (NDE) of a leading edge chine detected on imbedded delamination near the lower surface of the part. An ultimate proof test was conducted to verify the ultimate strength of this leading edge chine part. The ultimate proof test setup used a pressure bladder design to impose a uniform distributed pressure field over the bi-planar surface of the chine test article. A detailed description of the chine test article and experimental test setup is presented. Analysis results from a linear status model of the test article are also presented and discussed. Post-test inspection of the specimen revealed no visible failures or areas of delamination.

Evaluation of a head-repositioner and Z-plate system for improved accuracy of dose delivery.

PubMed

Charney, Sarah C; Lutz, Wendell R; Klein, Mary K; Jones, Pamela D

2009-01-01

Radiation therapy requires accurate dose delivery to targets often identifiable only on computed tomography (CT) images. Translation between the isocenter localized on CT and laser setup for radiation treatment, and interfractional head repositioning are frequent sources of positioning error. The objective was to design a simple, accurate apparatus to eliminate these sources of error. System accuracy was confirmed with phantom and in vivo measurements. A head repositioner that fixates the maxilla via dental mold with fiducial marker Z-plates attached was fabricated to facilitate the connection between the isocenter on CT and laser treatment setup. A phantom study targeting steel balls randomly located within the head repositioner was performed. The center of each ball was marked on a transverse CT slice on which six points of the Z-plate were also visible. Based on the relative position of the six Z-plate points and the ball center, the laser setup position on each Z-plate and a top plate was calculated. Based on these setup marks, orthogonal port films, directed toward each target, were evaluated for accuracy without regard to visual setup. A similar procedure was followed to confirm accuracy of in vivo treatment setups in four dogs using implanted gold seeds. Sequential port films of three dogs were made to confirm interfractional accuracy. Phantom and in vivo measurements confirmed accuracy of 2 mm between isocenter on CT and the center of the treatment dose distribution. Port films confirmed similar accuracy for interfractional treatments. The system reliably connects CT target localization to accurate initial and interfractional radiation treatment setup.

Channel electron multiplier compatibility with Viton and Apiezon-L vacuum grease

NASA Astrophysics Data System (ADS)

McComas, D. J.; Baldonado, J. R.; Bame, S. J.; Barraclough, B. L.

1987-12-01

Clean Viton and Viton coated with Apiezon-L vacuum grease were tested for their noncontaminating compatibility with channel electron multipliers (CEMs). The test setup and procedure were the same as those used previously in conjunction with CEM compatibility tests of certain epoxies, solder, and fluorocarbon polymer materials useful for construction of spaceflight sensors. While some CEM gain degradation was noted during exposure to Viton and Apiezon-L, the present tests indicate that, at least over instrument lifetimes of about 2 x 10 to the 12th counts, these materials should be suitable for (1) preflight space sensor testing systems, (2) hermetic seals for CEM-based space sensors, and (3) terrestrial CEM-based instrumentation.

Development of an ultrasensitive interferometry system as a key to precision metrology applications

NASA Astrophysics Data System (ADS)

Gohlke, Martin; Schuldt, Thilo; Weise, Dennis; Johann, Ulrich; Peters, Achim; Braxmaier, Claus

2009-06-01

We present a symmetric heterodyne interferometer as a prototype of a highly sensitive translation and tilt measurement system. This compact optical metrology system was developed over the past several years by EADS Astrium (Friedrichshafen) in cooperation with the Humboldt-University (Berlin) and the university of applied science Konstanz (HTWG-Konstanz). The noise performance was tested at frequencies between 10-4 and 3 Hz, the noise levels are below 1 nm/Hz 1/2 for translation and below 1 μrad/Hz1/2, for tilt measurements. For frequencies higher than 10 mHz noise levels below 5pm/Hz1/2 and 4 nrad/Hz1/2 respectively, were demonstrated. Based on this highly sensitive metrology system we also developed a dilatometer for the characterization of the CTE (coefficient of thermal expansion) of various materials, i.e. CFRP (carbon fiber reinforced plastic) or Zerodur. The currently achieved sensitivity of these measurements is better than 10-7 K-1. Future planned applications of the interferometer include ultra-high-precision surface profiling and characterization of actuator noise in low-noise opto-mechanics setups. We will give an overview of the current experimental setup and the latest measurement results.

Photogrammetry of the Map Instrument in a Cryogenic Vacuum Environment

NASA Technical Reports Server (NTRS)

Hill, M.; Packard, E.; Pazar, R.

2000-01-01

MAP Instrument requirements dictated that the instruments Focal Plane Assembly (FPA) and Thermal Reflector System (TRS) maintain a high degree of structural integrity at operational temperatures (< 50K). To verify integrity at these extremes, an elaborate test fixture was constructed to provide a large cryogenic (< 20K) radiative environment and a mobile photogrammetry camera. This paper will discuss MAP's Instrument requirements, how those requirements were verified using photogrammetry, and the test setup used to provide the environment and camera movement needed to verify the instrument's requirements.

Flying qualities criteria for GA single pilot IFR operations

NASA Technical Reports Server (NTRS)

Bar-Gill, A.

1982-01-01

The flying qualities criteria in general aviation (GA) to decrease accidents are discussed. The following in-flight research is discussed: (1) identification of key aerodynamic configurations; (2) implementation of an in-flight simulator; (3) mission matrix design; (4) experimental systems; (5) data reduction; (6) optimal flight path reconstruction. Some of the accomplished work is reported: an integrated flight testing and flight path reconstruction methodology was developd, high accuracy in trajectory estimation was achieved with an experimental setup, and a part of the flight test series was flown.

A new beam diagnostic system for the MASHA setup

NASA Astrophysics Data System (ADS)

Motycak, S.; Rodin, A. M.; Novoselov, A. S.; Podshibyakin, A. V.; Krupa, L.; Belozerov, A. V.; Vedeneyev, V. Yu.; Gulyaev, A. V.; Gulyaeva, A. V.; Kliman, J.; Salamatin, V. S.; Stepantsov, S. V.; Chernysheva, E. V.; Yuchimchuk, S. A.; Komarov, A. B.; Kamas, D.

2016-09-01

A new beam diagnostic system based on the PXI standard was developed, tested, and used in the MASHA setup experiment. The beam energy and beam current measurements were carried out using several methods. The online time-of-flight energy measurements were carried out using three pick-up detectors. We used two electronic systems to measure the time between the pick-ups. The first system was based on fast Agilent digitizers (2-channel, 4-GHz sampling rate), and the second one was based on a constant fraction discriminator (CFD) connected to a time-to-digital converter (TDC, 5-ps resolution). A new graphical interface to monitor the electronic devices and to perform the online calculations of energy was developed using MFC C++. The second system based on microchannel plate (time-of-flight) and silicon detectors for the determination of beam energy and the type of accelerated particles was also used. The beam current measurements were carried out with two different sensors. The first sensor is a rotating Faraday cup placed in front of the target, and the second one is an emission detector installed at the rear of the target. This system is now used in experiments for the synthesis of superheavy elements at the U400M cyclotron of the Flerov Laboratory of Nuclear Reactions (FLNR).

Communication Architecture in Mixed-Reality Simulations of Unmanned Systems

PubMed Central

2018-01-01

Verification of the correct functionality of multi-vehicle systems in high-fidelity scenarios is required before any deployment of such a complex system, e.g., in missions of remote sensing or in mobile sensor networks. Mixed-reality simulations where both virtual and physical entities can coexist and interact have been shown to be beneficial for development, testing, and verification of such systems. This paper deals with the problems of designing a certain communication subsystem for such highly desirable realistic simulations. Requirements of this communication subsystem, including proper addressing, transparent routing, visibility modeling, or message management, are specified prior to designing an appropriate solution. Then, a suitable architecture of this communication subsystem is proposed together with solutions to the challenges that arise when simultaneous virtual and physical message transmissions occur. The proposed architecture can be utilized as a high-fidelity network simulator for vehicular systems with implicit mobility models that are given by real trajectories of the vehicles. The architecture has been utilized within multiple projects dealing with the development and practical deployment of multi-UAV systems, which support the architecture’s viability and advantages. The provided experimental results show the achieved similarity of the communication characteristics of the fully deployed hardware setup to the setup utilizing the proposed mixed-reality architecture. PMID:29538290

Communication Architecture in Mixed-Reality Simulations of Unmanned Systems.

PubMed

Selecký, Martin; Faigl, Jan; Rollo, Milan

2018-03-14

Verification of the correct functionality of multi-vehicle systems in high-fidelity scenarios is required before any deployment of such a complex system, e.g., in missions of remote sensing or in mobile sensor networks. Mixed-reality simulations where both virtual and physical entities can coexist and interact have been shown to be beneficial for development, testing, and verification of such systems. This paper deals with the problems of designing a certain communication subsystem for such highly desirable realistic simulations. Requirements of this communication subsystem, including proper addressing, transparent routing, visibility modeling, or message management, are specified prior to designing an appropriate solution. Then, a suitable architecture of this communication subsystem is proposed together with solutions to the challenges that arise when simultaneous virtual and physical message transmissions occur. The proposed architecture can be utilized as a high-fidelity network simulator for vehicular systems with implicit mobility models that are given by real trajectories of the vehicles. The architecture has been utilized within multiple projects dealing with the development and practical deployment of multi-UAV systems, which support the architecture's viability and advantages. The provided experimental results show the achieved similarity of the communication characteristics of the fully deployed hardware setup to the setup utilizing the proposed mixed-reality architecture.

SU-F-J-44: Development of a Room Laser Based Real-Time Alignment Monitoring System Using An Array of Photodiodes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Noh, Y; Kim, T; Kang, S

2016-06-15

Purpose: To develop a real-time alignment monitoring system (RAMS) to compensate for the limitations of the conventional room laser based alignment system, and to verify the feasibility of the RAMS. Methods: The RAMS was composed of a room laser sensing array (RLSA), an analog-todigital converter, and a control PC. In the RLSA, seven photodiodes (each in 1 mm width) are arranged in a pattern that the RAMS provides alignment in 1 mm resolution. It works based on detecting laser light aligned on one of photodiodes. When misaligned, the laser would match with different photodiode(s) giving signal at unexpected location. Thus,more » how much displaced can be determined. To verify the reproducibility of the system with respect to time as well as repeated set-ups, temporal reproducibility and repeatability test was conducted. The accuracy of the system was tested by obtaining detection signals with varying laser-match positions. Results: The signal of the RAMS was found to be stable with respect to time. The repeatability test resulted in a maximum coefficient of variance of 1.14%, suggesting that the signal of the RAMS was stable over repeated set-ups. In the accuracy test, signals between when the laser was aligned and notaligned with any of sensors could be distinguished by signal intensity. The signals of not-aligned sensors were always below 75% of the signal of the aligned sensor. It was confirmed that the system could detect 1 mm of movement by monitoring the pattern of signals, and could observe the movement of the system in real-time. Conclusion: We developed a room laser based alignment monitoring system. The feasibility test verified that the system is capable of quantitative alignment monitoring in real time. The system is relatively simple, not expensive, and considered to be easily incorporated into conventional room laser systems for real-time alignment monitoring. This research was supported by the Mid-career Researcher Program through NRF funded by the Ministry of Science, ICT & Future Planning of Korea (NRF-2014R1A2A1A10050270) and by the Radiation Technology R&D program through the National Research Foundation of Korea funded by the Ministry of Science, ICT & Future Planning (No. 2013M2A2A7038291)« less

Study on the quality and stability of compost through a Demo Compost Plant.

PubMed

Hasan, K M M; Sarkar, G; Alamgir, M; Bari, Q H; Haedrich, G

2012-11-01

This study is concerned with the performance of a Demo Compost Plant for the development of acceptable composting technology in Bangladesh. The Demo Compost Plant was setup at the adjacent area of an existing compost plant located at Khulna city in Bangladesh. Four different composting technologies were considered, where Municipal Solid Waste (MSW) were used as a raw material for composting, collected from the adjacent areas of the plant. Initially the whole composting system was conducted through two experimental setups. In the 1st setup three different types of aerators (horizontal and vertical passively aerator and forced aerator) were selected. For a necessary observation four piles, using only MSW as the input materials in the first three compost pile, the fourth one was the existing Samadhan's compost pile. Based on the analysis of the experimental findings, the horizontal passively aerated composting technique is suitable for Bangladesh as it had better performance for reducing composting period than that of the others. It was being observed from the quality parameters of compost in the both 1st and 2nd setup that as the waste directly come from kitchen, degradation rate of waste shows a positive result for reducing this waste and there is no possibility of toxic contamination, when it would be used as a soil conditioner. Though there is no significant improvement in the quality of the final product in the 2nd setup as comparing with the 1st setup but it fulfills one of the main objectives of this study is to reduce the whole composting period as well as immediate management of the increasing amount of waste and reducing load on landfill. Selfheating tests reveal that degree of stability of compost with respect to maturation period was remained in the acceptable level, which was further accelerated due to the use of organic additives. Copyright © 2012 Elsevier Ltd. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zamora, D; Moirano, J; Kanal, K

Purpose: A fundamental measure performed during an annual physics CT evaluation confirms that system displayed CTDIvol nearly matches the independently measured value in phantom. For wide-beam (z-direction) CT scanners, AAPM Report 111 defined an ideal measurement method; however, the method often lacks practicality. The purpose of this preliminary study is to develop a set of conversion factors for a wide-beam CT scanner, relating the CTDIvol measured with a conventional setup (single CTDI phantom) versus the AAPM Report 111 approach (three abutting CTDI phantoms). Methods: For both the body CTDI and head CTDI, two acquisition setups were used: A) conventional singlemore » phantom and B) triple phantom. Of primary concern were the larger nominal beam widths for which a standard CTDI phantom setup would not provide adequate scatter conditions. Nominal beam width (160 or 120 mm) and kVp (100, 120, 140) were modulated based on the underlying clinical protocol. Exposure measurements were taken using a CT pencil ion chamber in the center and 12 o’clock position, and CTDIvol was calculated with ‘nT’ limited to 100 mm. A conversion factor (CF) was calculated as the ratio of CTDIvol measured in setup B versus setup A. Results: For body CTDI, the CF ranged from 1.04 up to 1.10, indicating a 4–10% difference between usage of one and three phantoms. For a nominal beam width of 160 mm, the CF did vary with selected kVp. For head CTDI at nominal beam widths of 120 and 160 mm, the CF was 1.00 and 1.05, respectively, independent of the kVp used (100, 120, and 140). Conclusions: A clear understanding of the manufacturer method of estimating the displayed CTDIvol is important when interpreting annual test results, as the acquisition setup may lead to an error of up to 10%. With appropriately defined CF, single phantom use is feasible.« less

Wave and setup dynamics on steeply-sloping reefs with large bottom roughness

NASA Astrophysics Data System (ADS)

Buckley, M. L.; Hansen, J.; Lowe, R.

2016-12-01

High-resolution observations from a wave flume were used to investigate the dynamics of wave setup over a steeply-sloping fringing reef profile with the effect of bottom roughness modeled using roughness elements scaled to mimic a coral reef. Results with roughness were compared with smooth bottom runs across sixteen offshore wave and still water level conditions. The time-averaged and depth-integrated force balance was evaluated from observations collected at seventeen locations across the flume, which was found to consist of cross-shore pressure and radiation stress gradients whose sum was balanced by mean quadratic bottom stresses. We found that when radiation stress gradients were calculated from observations of the radiation stress derived from linear wave theory, both wave setdown and setup were under predicted for the majority of wave and water level conditions tested. Inaccuracies in the predicted setdown and setup were improved by including a wave roller model, which provides a correction to the kinetic energy predicted by linear wave theory for breaking waves and produces a spatial delay in the wave forcing that was consistent with the observations. The introduction of roughness had two primary effects. First, the amount of wave energy dissipated during wave breaking was reduced due to frictional wave dissipation that occurred on the reef slope offshore of the breakpoint. Second, offshore directed mean bottom stresses were generated by the interaction of the combined wave-current velocity field with the roughness elements. These two mechanisms acted counter to one another. As a result, setup on the reef flat was comparable (7% mean difference) between corresponding rough and smooth runs. These findings are used to assess prior results from numerical modelling studies of reefs, and also to discuss the broader implications for how steep slopes and large roughness influences setup dynamics for general nearshore systems.

Percentage depth dose calculation accuracy of model based algorithms in high energy photon small fields through heterogeneous media and comparison with plastic scintillator dosimetry.

PubMed

Alagar, Ananda Giri Babu; Mani, Ganesh Kadirampatti; Karunakaran, Kaviarasu

2016-01-08

Small fields smaller than 4 × 4 cm2 are used in stereotactic and conformal treatments where heterogeneity is normally present. Since dose calculation accuracy in both small fields and heterogeneity often involves more discrepancy, algorithms used by treatment planning systems (TPS) should be evaluated for achieving better treatment results. This report aims at evaluating accuracy of four model-based algorithms, X-ray Voxel Monte Carlo (XVMC) from Monaco, Superposition (SP) from CMS-Xio, AcurosXB (AXB) and analytical anisotropic algorithm (AAA) from Eclipse are tested against the measurement. Measurements are done using Exradin W1 plastic scintillator in Solid Water phantom with heterogeneities like air, lung, bone, and aluminum, irradiated with 6 and 15 MV photons of square field size ranging from 1 to 4 cm2. Each heterogeneity is introduced individually at two different depths from depth-of-dose maximum (Dmax), one setup being nearer and another farther from the Dmax. The central axis percentage depth-dose (CADD) curve for each setup is measured separately and compared with the TPS algorithm calculated for the same setup. The percentage normalized root mean squared deviation (%NRMSD) is calculated, which represents the whole CADD curve's deviation against the measured. It is found that for air and lung heterogeneity, for both 6 and 15 MV, all algorithms show maximum deviation for field size 1 × 1 cm2 and gradually reduce when field size increases, except for AAA. For aluminum and bone, all algorithms' deviations are less for 15 MV irrespective of setup. In all heterogeneity setups, 1 × 1 cm2 field showed maximum deviation, except in 6MV bone setup. All algorithms in the study, irrespective of energy and field size, when any heterogeneity is nearer to Dmax, the dose deviation is higher compared to the same heterogeneity far from the Dmax. Also, all algorithms show maximum deviation in lower-density materials compared to high-density materials.

Bathymetric surveying with GPS and heave, pitch, and roll compensation

USGS Publications Warehouse

Work, P.A.; Hansen, M.; Rogers, W.E.

1998-01-01

Field and laboratory tests of a shipborne hydrographic survey system were conducted. The system consists of two 12-channel GPS receivers (one on-board, one fixed on shore), a digital acoustic fathometer, and a digital heave-pitch-roll (HPR) recorder. Laboratory tests of the HPR recorder and fathometer are documented. Results of field tests of the isolated GPS system and then of the entire suite of instruments are presented. A method for data reduction is developed to account for vertical errors introduced by roll and pitch of the survey vessel, which can be substantial (decimeters). The GPS vertical position data are found to be reliable to 2-3 cm and the fathometer to 5 cm in the laboratory. The field test of the complete system in shallow water (<2 m) indicates absolute vertical accuracy of 10-20 cm. Much of this error is attributed to the fathometer. Careful surveying and equipment setup can minimize systematic error and yield much smaller average errors.

Restrictive loads powered by separate or by common electrical sources

NASA Technical Reports Server (NTRS)

Appelbaum, J.

1989-01-01

In designing a multiple load electrical system, the designer may wish to compare the performance of two setups: a common electrical source powering all loads, or separate electrical sources powering individual loads. Three types of electrical sources: an ideal voltage source, an ideal current source, and solar cell source powering resistive loads were analyzed for their performances in separate and common source systems. A mathematical proof is given, for each case, indicating the merit of the separate or common source system. The main conclusions are: (1) identical resistive loads powered by ideal voltage sources perform the same in both system setups, (2) nonidentical resistive loads powered by ideal voltage sources perform the same in both system setups, (3) nonidentical resistive loads powered by ideal current sources have higher performance in separate source systems, and (4) nonidentical resistive loads powered by solar cells have higher performance in a common source system for a wide range of load resistances.

Investigation of nanoyarn preparation by modified electrospinning setup.

PubMed

Levitt, Ariana S; Knittel, Chelsea E; Vallett, Richard; Koerner, Michael; Dion, Genevieve; Schauer, Caroline L

2017-05-15

Higher ordered structures of nanofibers, including nanofiber-based yarns and cables, have a variety of potential applications, including wearable health monitoring systems, artificial tendons, and medical sutures. In this study, twisted assemblies of polyacrylonitrile (PAN), polyvinylidene fluoride trifluoroethylene (PVDF-TrFE), and polycaprolactone (PCL) nanofibers were fabricated via a modified electrospinning setup, consisting of a rotating cone-shaped copper collector, two syringe pumps, and two high voltage power supplies. The fiber diameters and twist angles varied as a function of the rotary speed of the collector. Mechanical testing of the yarns revealed that PVDF-TrFe and PCL yarns have a higher strain-to-failure than PAN yarns, reaching 307% for PCL nanoyarns. For the first time, the porosity of nanofiber yarns was studied as a function of twist angle, showing that PAN nanoyarns are more porous than PCL yarns.

Characterization of a Setup to test the Impact of High-Amplitude Pressure Waves on Living Cells

PubMed Central

Schmidt, Mischa; Kahlert, Ulf; Wessolleck, Johanna; Maciaczyk, Donata; Merkt, Benjamin; Maciaczyk, Jaroslaw; Osterholz, Jens; Nikkhah, Guido; Steinhauser, Martin O.

2014-01-01

The impact of pressure waves on cells may provide several possible applications in biology and medicine including the direct killing of tumors, drug delivery or gene transfection. In this study we characterize the physical properties of mechanical pressure waves generated by a nanosecond laser pulse in a setup with well-defined cell culture conditions. To systematically characterize the system on the relevant length and time scales (micrometers and nanoseconds) we use photon Doppler velocimetry (PDV) and obtain velocity profiles of the cell culture vessel at the passage of the pressure wave. These profiles serve as input for numerical pressure wave simulations that help to further quantify the pressure conditions on the cellular length scale. On the biological level we demonstrate killing of glioblastoma cells and quantify experimentally the pressure threshold for cell destruction. PMID:24458018

Characterization of a neutron imaging setup at the INES facility

NASA Astrophysics Data System (ADS)

Durisi, E. A.; Visca, L.; Albertin, F.; Brancaccio, R.; Corsi, J.; Dughera, G.; Ferrarese, W.; Giovagnoli, A.; Grassi, N.; Grazzi, F.; Lo Giudice, A.; Mila, G.; Nervo, M.; Pastrone, N.; Prino, F.; Ramello, L.; Re, A.; Romero, A.; Sacchi, R.; Salvemini, F.; Scherillo, A.; Staiano, A.

2013-10-01

The Italian Neutron Experimental Station (INES) located at the ISIS pulsed neutron source (Didcot, United Kingdom) provides a thermal neutron beam mainly used for diffraction analysis. A neutron transmission imaging system was also developed for beam monitoring and for aligning the sample under investigation. Although the time-of-flight neutron diffraction is a consolidated technique, the neutron imaging setup is not yet completely characterized and optimized. In this paper the performance for neutron radiography and tomography at INES of two scintillator screens read out by two different commercial CCD cameras is compared in terms of linearity, signal-to-noise ratio, effective dynamic range and spatial resolution. In addition, the results of neutron radiographies and a tomography of metal alloy test structures are presented to better characterize the INES imaging capabilities of metal artifacts in the cultural heritage field.

Modeling flow and solute transport at a tile drain field site by explicit representation of preferential flow structures: Equifinality and uncertainty

NASA Astrophysics Data System (ADS)

Zehe, E.; Klaus, J.

2011-12-01

Rapid flow in connected preferential flow paths is crucial for fast transport of water and solutes through soils, especially at tile drained field sites. The present study tests whether an explicit treatment of worm burrows is feasible for modeling water flow, bromide and pesticide transport in structured heterogeneous soils with a 2-dimensional Richards based model. The essence is to represent worm burrows as morphologically connected paths of low flow resistance and low retention capacity in the spatially highly resolved model domain. The underlying extensive database to test this approach was collected during an irrigation experiment, which investigated transport of bromide and the herbicide Isoproturon at a 900 sqm tile drained field site. In a first step we investigated whether the inherent uncertainty in key data causes equifinality i.e. whether there are several spatial model setups that reproduce tile drain event discharge in an acceptable manner. We found a considerable equifinality in the spatial setup of the model, when key parameters such as the area density of worm burrows and the maximum volumetric water flows inside these macropores were varied within the ranges of either our measurement errors or measurements reported in the literature. Thirteen model runs yielded a Nash-Sutcliffe coefficient of more than 0.9. Also, the flow volumes were in good accordance and peak timing errors where less than or equal to 20 min. In the second step we investigated thus whether this "equifinality" in spatial model setups may be reduced when including the bromide tracer data into the model falsification process. We simulated transport of bromide for the 13 spatial model setups, which performed best with respect to reproduce tile drain event discharge, without any further calibration. Four of this 13 model setups allowed to model bromide transport within fixed limits of acceptability. Parameter uncertainty and equifinality could thus be reduced. Thirdly, we selected one of those four setups for simulating transport of Isoproturon, which was applied the day before the irrigation experiment, and tested different parameter combinations to characterise adsorption according to the footprint data base. Simulations could, however, only reproduce the observed event based leaching behaviour, when we allowed for retardation coefficients that were very close to one. This finding is consistent with observations various field observations. We conclude: a) A realistic representation of dominating structures and their topology is of key importance for predicting preferential water and mass flows at tile drained hillslopes. b) Parameter uncertainty and equifinality could be reduced, but a system inherent equifinality in a 2-dimensional Richards based model has to be accepted.

Design and Testing of a One-Meter Membrane Mirror with Active Boundary Control (Conference Proceedings)

DTIC Science & Technology

2005-08-01

One type of setup looked into in the past has been the lenticular design, which consists of a clear canopy attached to a reflective film that uses...class lenticular membrane mirror system utilizing active boundary control and stress-coating applications to form a usable aperture for visible...imaging applications. Keywords: Membrane mirror, boundary control, lenticular , lightweight 1. INTRODUCTION Analysis has been conducted to

Caracterización y automatización mecánica de los telescopios Cherenkov de CASLEO

NASA Astrophysics Data System (ADS)

Leal, N.; Yelós, L. D.; Mancilla, A.; Maya, J.; Feres, L.; Lazarte, F.; García, B.

2017-10-01

A new automation system for the Cherenkov Telescopes at CASLEO is designed. Two rotation speeds are proposed: a fast speed for positioning and parking and a slow speed for tracking. The wind speed at El Leoncito site is used as a design parameter. In this work we present the first tests with the new setup which shows a correct performance at fast speeds.

LV software support for supersonic flow analysis

NASA Technical Reports Server (NTRS)

Bell, William A.

1991-01-01

During 1991, the software developed allowed an operator to configure and checkout the TSI, Inc. laser velocimeter (LV) system prior to a run. This setup procedure established the operating conditions for the TSI MI-990 multichannel interface and the RMR-1989 rotating machinery resolver. In addition to initializing the instruments, the software package provides a means of specifying LV calibration constants, controlling the sampling process, and identifying the test parameters.

Long-term monitoring of marine gas leakage

NASA Astrophysics Data System (ADS)

Spickenbom, Kai; Faber, Eckhard; Poggenburg, Jürgen; Seeger, Christian; Furche, Markus

2010-05-01

The sequestration of CO2 in sub-seabed geological formations is one of the Carbon Capture and Storage (CCS) strategies currently under study. Although offshore operations are significantly more expensive than comparable onshore operations, the growing public resistance against onshore CCS projects makes sub-seabed storage a promising option. Even after a thorough review of the geological setting, there is always the possibility of leakage from the reservoir. As part of the EU-financed project CO2ReMoVe (Research, Monitoring, Verification), which aims to develop innovative research and technologies for monitoring and verification of carbon dioxide geological storage, we are working on the development of submarine long-term gas flow monitoring systems. The basic design of the monitoring system builds on our experience in volcano monitoring. Early prototypes were composed of a raft floating on the surface of a mud volcano, carrying sensors for CO2 flux and concentration, data storage and transmission, and power supply by battery-buffered solar panels. The system was modified for installation in open sea by using a buoy instead of a raft and a funnel on the seafloor to collect the gas, connected by a flexible tube. This setup provides a cost-effective solution for shallow waters. However, a buoy interferes with ship traffic, and it is also difficult to adapt this design to greater water depths. These requirements can best be complied by a completely submersed system. A system for unattended long-term monitoring in a marine environment has to be extremely durable. Therefore, we focussed on developing a mechanically and electrically as simple setup as possible, which has the additional advantage of low cost. The system consists of a funnel-shaped gas collector, a sensor head and pressure housings for electronics and power supply. Since this setup is inexpensive, it can be deployed in numbers to cover larger areas. By addition of multi-channel data loggers, data transmission by acoustic modem or cable, relay stations on the seafloor or buoys etc. the infrastructure can be adapted to the environmental setting and financial budget. Prototype tests under laboratory conditions as well as field tests on natural submarine gas vents as an analogue to leaking storage sites have demonstrated the capabilities and robustness of the systems.

Initial clinical experience with a video-based patient positioning system.

PubMed

Johnson, L S; Milliken, B D; Hadley, S W; Pelizzari, C A; Haraf, D J; Chen, G T

1999-08-01

To report initial clinical experience with an interactive, video-based patient positioning system that is inexpensive, quick, accurate, and easy to use. System hardware includes two black-and-white CCD cameras, zoom lenses, and a PC equipped with a frame grabber. Custom software is used to acquire and archive video images, as well as to display real-time subtraction images revealing patient misalignment in multiple views. Two studies are described. In the first study, video is used to document the daily setup histories of 5 head and neck patients. Time-lapse cine loops are generated for each patient and used to diagnose and correct common setup errors. In the second study, 6 twice-daily (BID) head and neck patients are positioned according to the following protocol: at AM setups conventional treatment room lasers are used; at PM setups lasers are used initially and then video is used for 1-2 minutes to fine-tune the patient position. Lateral video images and lateral verification films are registered off-line to compare the distribution of setup errors per patient, with and without video assistance. In the first study, video images were used to determine the accuracy of our conventional head and neck setup technique, i.e., alignment of lightcast marks and surface anatomy to treatment room lasers and the light field. For this initial cohort of patients, errors ranged from sigma = 5 to 7 mm and were patient-specific. Time-lapse cine loops of the images revealed sources of the error, and as a result, our localization techniques and immobilization device were modified to improve setup accuracy. After the improvements, conventional setup errors were reduced to sigma = 3 to 5 mm. In the second study, when a stereo pair of live subtraction images were introduced to perform daily "on-line" setup correction, errors were reduced to sigma = 1 to 3 mm. Results depended on patient health and cooperation and the length of time spent fine-tuning the position. An interactive, video-based patient positioning system was shown to reduce setup errors to within 1 to 3 mm in head and neck patients, without a significant increase in overall treatment time or labor-intensive procedures. Unlike retrospective portal image analysis, use of two live-video images provides the therapists with immediate feedback and allows for true 3-D positioning and correction of out-of-plane rotation before radiation is delivered. With significant improvement in head and neck alignment and the elimination of setup errors greater than 3 to 5 mm, margins associated with treatment volumes potentially can be reduced, thereby decreasing normal tissue irradiation.

Radiated Susceptibility Test Procedure and Setup Exploiting Crosstalk

NASA Astrophysics Data System (ADS)

Grassi, F.; Pignari, S. A.; Spadacini, G.; Bisognin, P.; Pelissou, P.; Marra, S.

2016-05-01

In this work, basic principles of an alternative test procedure exploiting crosstalk to reproduce in the terminal loads of a wiring structure the same disturbances that would be induced by traditional radiated susceptibility (RS) tests are presented. Equivalence with radiation is achieved by the use of a generator circuit properly fed with two synchronized RF generators, and holds for whatever loads (even not linear) connected to the terminations of the cable harness. The proposed procedure is here tailored to the specific conditions of incidence foreseen by aerospace Standards on RS. Its effectiveness is validated by measurements carried out in an ad hoc test setup.

The study on injection parameters of selected alternative fuels used in diesel engines

NASA Astrophysics Data System (ADS)

Balawender, K.; Kuszewski, H.; Lejda, K.; Lew, K.

2016-09-01

The paper presents selected results concerning fuel charging and spraying process for selected alternative fuels, including regular diesel fuel, rape oil, FAME, blends of these fuels in various proportions, and blends of rape oil with diesel fuel. Examination of the process included the fuel charge measurements. To this end, a set-up for examination of Common Rail-type injection systems was used constructed on the basis of Bosch EPS-815 test bench, from which the high-pressure pump drive system was adopted. For tests concerning the spraying process, a visualisation chamber with constant volume was utilised. The fuel spray development was registered with the use of VisioScope (AVL).

The effect of systematic set-up deviations on the absorbed dose distribution for left-sided breast cancer treated with respiratory gating

NASA Astrophysics Data System (ADS)

Edvardsson, A.; Ceberg, S.

2013-06-01

The aim of this study was 1) to investigate interfraction set-up uncertainties for patients treated with respiratory gating for left-sided breast cancer, 2) to investigate the effect of the inter-fraction set-up on the absorbed dose-distribution for the target and organs at risk (OARs) and 3) optimize the set-up correction strategy. By acquiring multiple set-up images the systematic set-up deviation was evaluated. The effect of the systematic set-up deviation on the absorbed dose distribution was evaluated by 1) simulation in the treatment planning system and 2) measurements with a biplanar diode array. The set-up deviations could be decreased using a no action level correction strategy. Not using the clinically implemented adaptive maximum likelihood factor for the gating patients resulted in better set-up. When the uncorrected set-up deviations were simulated the average mean absorbed dose was increased from 1.38 to 2.21 Gy for the heart, 4.17 to 8.86 Gy to the left anterior descending coronary artery and 5.80 to 7.64 Gy to the left lung. Respiratory gating can induce systematic set-up deviations which would result in increased mean absorbed dose to the OARs if not corrected for and should therefore be corrected for by an appropriate correction strategy.

Analysis and Ground Testing for Validation of the Inflatable Sunshield in Space (ISIS) Experiment

NASA Technical Reports Server (NTRS)

Lienard, Sebastien; Johnston, John; Adams, Mike; Stanley, Diane; Alfano, Jean-Pierre; Romanacci, Paolo

2000-01-01

The Next Generation Space Telescope (NGST) design requires a large sunshield to protect the large aperture mirror and instrument module from constant solar exposure at its L2 orbit. The structural dynamics of the sunshield must be modeled in order to predict disturbances to the observatory attitude control system and gauge effects on the line of site jitter. Models of large, non-linear membrane systems are not well understood and have not been successfully demonstrated. To answer questions about sunshield dynamic behavior and demonstrate controlled deployment, the NGST project is flying a Pathfinder experiment, the Inflatable Sunshield in Space (ISIS). This paper discusses in detail the modeling and ground-testing efforts performed at the Goddard Space Flight Center to: validate analytical tools for characterizing the dynamic behavior of the deployed sunshield, qualify the experiment for the Space Shuttle, and verify the functionality of the system. Included in the discussion will be test parameters, test setups, problems encountered, and test results.

Small-Scale Hybrid Rocket Test Stand & Characterization of Swirl Injectors

NASA Astrophysics Data System (ADS)

Summers, Matt H.

Derived from the necessity to increase testing capabilities of hybrid rocket motor (HRM) propulsion systems for Daedalus Astronautics at Arizona State University, a small-scale motor and test stand were designed and developed to characterize all components of the system. The motor is designed for simple integration and setup, such that both the forward-end enclosure and end cap can be easily removed for rapid integration of components during testing. Each of the components of the motor is removable allowing for a broad range of testing capabilities. While examining injectors and their potential it is thought ideal to obtain the highest regression rates and overall motor performance possible. The oxidizer and fuel are N2O and hydroxyl-terminated polybutadiene (HTPB), respectively, due to previous experience and simplicity. The injector designs, selected for the same reasons, are designed such that they vary only in the swirl angle. This system provides the platform for characterizing the effects of varying said swirl angle on HRM performance.

Toyota's inspection system for vehicular emissions at assembly lines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tanaka, T.; Nakano, H.; Usami, I.

1976-01-01

In order that all Toyota production vehicles may satisfy the emission requirements and be free from possible defects such as catalytic converter damage, a system called ECAS, which allows us to assure satisfactory basic emission performance levels has been developed and put into actual use at assembly lines. This system consists of the following four tests: Idle Test, Functional Test, Short Cycle Test and Steady State Inspection Test. By using this system, all operations from vehicle setup, on a chassis dynamometer to statistical analysis of the data, measurement, judgement of the obtained data, type-out of the results, indication for actionmore » to be taken, data filing and statistical treatment of the data, are processed automatically and controlled by the computer. In the Short Cycle Test the up-stream emissions of the vehicle, tracing Toyota's unique short cyclic mode on a chassis dynamometer, are continuously measured. Based on the emission levels during each mode and the total emission level obtained from the above test we can diagnose, not only the emission control systems of a vehicle and its engine conditions such as valve clearance maladjustment and carburetor defects, but also the emission characteristics of this vehicle.« less

Direct Field Acoustic Testing

NASA Technical Reports Server (NTRS)

Larkin, Paul; Goldstein, Bob

2008-01-01

This paper presents an update to the methods and procedures used in Direct Field Acoustic Testing (DFAT). The paper will discuss some of the recent techniques and developments that are currently being used and the future publication of a reference standard. Acoustic testing using commercial sound system components is becoming a popular and cost effective way of generating a required acoustic test environment both in and out of a reverberant chamber. This paper will present the DFAT test method, the usual setup and procedure and the development and use of a closed-loop, narrow-band control system. Narrow-band control of the acoustic PSD allows all standard techniques and procedures currently used in random control to be applied to acoustics and some examples are given. The paper will conclude with a summary of the development of a standard practice guideline that is hoped to be available in the first quarter of next year.

Cold-end Subsystem Testing for the Fission Power System Technology Demonstration Unit

NASA Technical Reports Server (NTRS)

Briggs, Maxwell; Gibson, Marc; Ellis, David; Sanzi, James

2013-01-01

The Fission Power System (FPS) Technology Demonstration Unit (TDU) consists of a pumped sodium-potassium (NaK) loop that provides heat to a Stirling Power Conversion Unit (PCU), which converts some of that heat into electricity and rejects the waste heat to a pumped water loop. Each of the TDU subsystems is being tested independently prior to full system testing at the NASA Glenn Research Center. The pumped NaK loop is being tested at NASA Marshall Space Flight Center; the Stirling PCU and electrical controller are being tested by Sunpower Inc.; and the pumped water loop is being tested at Glenn. This paper describes cold-end subsystem setup and testing at Glenn. The TDU cold end has been assembled in Vacuum Facility 6 (VF 6) at Glenn, the same chamber that will be used for TDU testing. Cold-end testing in VF 6 will demonstrate functionality; validated cold-end fill, drain, and emergency backup systems; and generated pump performance and system pressure drop data used to validate models. In addition, a low-cost proof-of concept radiator has been built and tested at Glenn, validating the design and demonstrating the feasibility of using low-cost metal radiators as an alternative to high-cost composite radiators in an end-to-end TDU test.

Cold-End Subsystem Testing for the Fission Power System Technology Demonstration Unit

NASA Technical Reports Server (NTRS)

Briggs, Mazwell; Gibson, Marc; Ellis, David; Sanzi, James

2013-01-01

The Fission Power System (FPS) Technology Demonstration Unit (TDU) consists of a pumped sodiumpotassium (NaK) loop that provides heat to a Stirling Power Conversion Unit (PCU), which converts some of that heat into electricity and rejects the waste heat to a pumped water loop. Each of the TDU subsystems is being tested independently prior to full system testing at the NASA Glenn Research Center. The pumped NaK loop is being tested at NASA Marshall Space Flight Center; the Stirling PCU and electrical controller are being tested by Sunpower Inc.; and the pumped water loop is being tested at Glenn. This paper describes cold-end subsystem setup and testing at Glenn. The TDU cold end has been assembled in Vacuum Facility 6 (VF 6) at Glenn, the same chamber that will be used for TDU testing. Cold-end testing in VF 6 will demonstrate functionality; validated coldend fill, drain, and emergency backup systems; and generated pump performance and system pressure drop data used to validate models. In addition, a low-cost proof-of concept radiator has been built and tested at Glenn, validating the design and demonstrating the feasibility of using low-cost metal radiators as an alternative to highcost composite radiators in an end-to-end TDU test.

Dual Etalon Cross Tilt Order Sorted Spectrometer (DECTOSS)

NASA Astrophysics Data System (ADS)

Kumer, John B.; Rairden, Richard L.; Mitchell, Keith E.; Roche, Aidan E.; Mergenthaler, John L.

2002-11-01

The Dual Etalon Cross Tilt Order Sorted Spectrometer (DECTOSS) uses relatively inexpensive off the shelf components in a small and simple package to provide ultra high spectral resolution over a limited spectral range. For example, the modest first try laboratory test setup DECTOSS we describe in this presentation achieves resolving power ~ 105 on a spectral range of about 1 nm centered near 760 nm. This ultra high spectral resolution facilitates some important atmospheric remote sensing applications including profiling cirrus and/or aerosol above bright reflective surfaces in the O2 A-band and the column measurements of CO and CO2 utilizing solar reflectance spectra. We show details of the how the use of ultra high spectral resolution in the O2 A-band improves the profiling of cirrus and aerosol. The DECTOSS utilizes a Narrow Band Spectral Filter (NBSF), a Low Resolution Etalon (LRE) and a High Resolution Etalon (HRE). Light passing through these elements is focused on to a 2 Dimensional Array Detector (2DAD). Off the shelf, solid etalons with airgap or solid spacer gap are used in this application. In its simplest application this setup utilizes a spatially uniform extended source so that spatial and spectral structure are not confused. In this presentation we'll show 2D spectral data obtained in a desktop test configuration, and in the first try laboratory test setup. These were obtained by illuminating a Lambertian screen with (1) monochromatic light, and (2) with atmospheric absorption spectra in the oxygen (O2) A-band. Extracting the 1D spectra from these data is a work in progress and we show preliminary results compared with (1) solar absorption data obtained with a large Echelle grating spectrometer, and (2) theoretical spectra. We point out areas for improvement in our laboratory test setup, and general improvements in spectral range and sensitivity that are planned for our next generation field test setup.

Improved setup and positioning accuracy using a three‐point customized cushion/mask/bite‐block immobilization system for stereotactic reirradiation of head and neck cancer

PubMed Central

Wang, He; Wang, Congjun; Tung, Samuel; Dimmitt, Andrew Wilson; Wong, Pei Fong; Edson, Mark A.; Garden, Adam S.; Rosenthal, David I.; Fuller, Clifton D.; Gunn, Gary B.; Takiar, Vinita; Wang, Xin A.; Luo, Dershan; Yang, James N.; Wong, Jennifer

2016-01-01

The purpose of this study was to investigate the setup and positioning uncertainty of a custom cushion/mask/bite‐block (CMB) immobilization system and determine PTV margin for image‐guided head and neck stereotactic ablative radiotherapy (HN‐SABR). We analyzed 105 treatment sessions among 21 patients treated with HN‐SABR for recurrent head and neck cancers using a custom CMB immobilization system. Initial patient setup was performed using the ExacTrac infrared (IR) tracking system and initial setup errors were based on comparison of ExacTrac IR tracking system to corrected online ExacTrac X‐rays images registered to treatment plans. Residual setup errors were determined using repeat verification X‐ray. The online ExacTrac corrections were compared to cone‐beam CT (CBCT) before treatment to assess agreement. Intrafractional positioning errors were determined using prebeam X‐rays. The systematic and random errors were analyzed. The initial translational setup errors were −0.8±1.3 mm, −0.8±1.6 mm, and 0.3±1.9 mm in AP, CC, and LR directions, respectively, with a three‐dimensional (3D) vector of 2.7±1.4 mm. The initial rotational errors were up to 2.4° if 6D couch is not available. CBCT agreed with ExacTrac X‐ray images to within 2 mm and 2.5°. The intrafractional uncertainties were 0.1±0.6 mm, 0.1±0.6 mm, and 0.2±0.5 mm in AP, CC, and LR directions, respectively, and 0.0∘±0.5°, 0.0∘±0.6°, and −0.1∘±0.4∘ in yaw, roll, and pitch direction, respectively. The translational vector was 0.9±0.6 mm. The calculated PTV margins mPTV(90,95) were within 1.6 mm when using image guidance for online setup correction. The use of image guidance for online setup correction, in combination with our customized CMB device, highly restricted target motion during treatments and provided robust immobilization to ensure minimum dose of 95% to target volume with 2.0 mm PTV margin for HN‐SABR. PACS number(s): 87.55.ne PMID:27167275

Mechanical testing of advanced coating system, volume 1

NASA Technical Reports Server (NTRS)

Cruse, T. A.; Nagy, A.; Popelar, C. F.

1990-01-01

The Electron Beam Physical Vapor Deposition (EBPVD) coating material has a highly columnar microstructure, and as a result it was expected to have very low tensile strength. To be able to fabricate the required compression and tensile specimens, a substrate was required to provide structural integrity for the specimens. Substrate and coating dimensions were adjusted to provide sufficient sensitivity to resolve the projected loads carried by the EBPVD coating. The use of two distinctively different strain transducer systems, for tension and compression loadings, mandated two vastly different specimen geometries. Compression specimen and tensile specimen geometries are given. Both compression and tensile test setups are described. Data reduction mathematical models are given and discussed in detail as is the interpretation of the results. Creep test data is also given and discussed.

MO-FG-CAMPUS-JeP3-02: A Novel Setup Approach to Improve C-Spine Curvature Reproducibility for Head and Neck Radiotherapy Using Optical Surface Imaging with Two Regions of Interest

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ryan, K; Gil, M; Li, G

Purpose: To develop a novel approach to improve cervical spine (c-spine) curvature reproducibility for head and neck (HN) patients using optical surface imaging (OSI) with two regions of interests (ROIs). Methods: The OSI-guided, two-step setup procedure requires two ROIs: ROI-1 of the shoulders and ROI-2 of the face. The neck can be stretched or squeezed in superior-inferior (SI) direction using a specially-designed sliding head support. We hypothesize that when these two ROIs are aligned, the c-spine should fall into a naturally reproducible position under same setup conditions. An anthropomorphous phantom test was performed to examine neck pitch angles comparing withmore » the calculated angles. Three volunteers participated in the experiments, which start with conventional HN setup using skin markers and room lasers. An OSI image and lateral photo-picture were acquired as the references. In each of the three replicate tests, conventional setup was first applied after volunteers got on the couch. ROI-1 was aligned by moving the body, followed by ROI-2 alignment via adjusting head position and orientation under real-time OSI guidance. A final static OSI image and lateral picture were taken to evaluate both anterior and posterior surface alignments. Three degrees of freedom can be adjusted if an open-face mask was applied, including head SI shift using the sliding head support and pitch-and-roll rotations using a commercial couch extension. Surface alignment was analyzed comparing with conventional setup. Results: The neck pitch angle measured by OSI is consistent with the calculated (0.2±0.6°). Volunteer study illustrated improved c-spine setup reproducibility using OSI comparing with conventional setup. ROI alignments with 2mm/1° tolerance are achieved within 3 minutes. Identical knee support is important to achieve ROI-1 pitch alignment. Conclusion: The feasibility of this novel approach has been demonstrated for c-spine curvature setup reproducibility. Further evaluation is necessary with bony alignment variation in patient studies. This study is in part supported by the NIH (U54CA137788).« less

Patterns of intrafractional motion and uncertainties of treatment setup reference systems in accelerated partial breast irradiation for right- and left-sided breast cancer.

PubMed

Yue, Ning J; Goyal, Sharad; Kim, Leonard H; Khan, Atif; Haffty, Bruce G

2014-01-01

This study investigated the patterns of intrafractional motion and accuracy of treatment setup strategies in 3-dimensional conformal radiation therapy of accelerated partial breast irradiation (APBI) for right- and left-sided breast cancers. Sixteen right-sided and 17 left-sided breast cancer patients were enrolled in an institutional APBI trial in which gold fiducial markers were strategically sutured to the surgical cavity walls. Daily pre- and postradiation therapy kV imaging were performed and were matched to digitally reconstructed radiographs based on bony anatomy and fiducial markers, respectively, to determine the intrafractional motion. The positioning differences of the laser-tattoo and the bony anatomy-based setups with respect to the marker-based setup (benchmark) were determined to evaluate their accuracy. Statistical differences were found between the right- and left-sided APBI treatments in vector directions of intrafractional motion and treatment setup errors in the reference systems, but less in their overall magnitudes. The directional difference was more pronounced in the lateral direction. It was found that the intrafractional motion and setup reference systems tended to deviate in the right direction for the right-sided breast treatments and in the left direction for the left-sided breast treatments. It appears that the fiducial markers placed in the seroma cavity exhibit side dependent directional intrafractional motion, although additional data may be needed to further validate the conclusion. The bony anatomy-based treatment setup improves the accuracy over laser-tattoo. But it is inadequate to rely on bony anatomy to assess intrafractional target motion in both magnitude and direction. Copyright © 2014 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

Automated patient identification and localization error detection using 2-dimensional to 3-dimensional registration of kilovoltage x-ray setup images.

PubMed

Lamb, James M; Agazaryan, Nzhde; Low, Daniel A

2013-10-01

To determine whether kilovoltage x-ray projection radiation therapy setup images could be used to perform patient identification and detect gross errors in patient setup using a computer algorithm. Three patient cohorts treated using a commercially available image guided radiation therapy (IGRT) system that uses 2-dimensional to 3-dimensional (2D-3D) image registration were retrospectively analyzed: a group of 100 cranial radiation therapy patients, a group of 100 prostate cancer patients, and a group of 83 patients treated for spinal lesions. The setup images were acquired using fixed in-room kilovoltage imaging systems. In the prostate and cranial patient groups, localizations using image registration were performed between computed tomography (CT) simulation images from radiation therapy planning and setup x-ray images corresponding both to the same patient and to different patients. For the spinal patients, localizations were performed to the correct vertebral body, and to an adjacent vertebral body, using planning CTs and setup x-ray images from the same patient. An image similarity measure used by the IGRT system image registration algorithm was extracted from the IGRT system log files and evaluated as a discriminant for error detection. A threshold value of the similarity measure could be chosen to separate correct and incorrect patient matches and correct and incorrect vertebral body localizations with excellent accuracy for these patient cohorts. A 10-fold cross-validation using linear discriminant analysis yielded misclassification probabilities of 0.000, 0.0045, and 0.014 for the cranial, prostate, and spinal cases, respectively. An automated measure of the image similarity between x-ray setup images and corresponding planning CT images could be used to perform automated patient identification and detection of localization errors in radiation therapy treatments. Copyright © 2013 Elsevier Inc. All rights reserved.

Six-flow operations for catalyst development in Fischer-Tropsch synthesis: Bridging the gap between high-throughput experimentation and extensive product evaluation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sartipi, Sina, E-mail: S.Sartipi@tudelft.nl, E-mail: J.Gascon@tudelft.nl; Jansma, Harrie; Bosma, Duco

2013-12-15

Design and operation of a “six-flow fixed-bed microreactor” setup for Fischer-Tropsch synthesis (FTS) is described. The unit consists of feed and mixing, flow division, reaction, separation, and analysis sections. The reactor system is made of five heating blocks with individual temperature controllers, assuring an identical isothermal zone of at least 10 cm along six fixed-bed microreactor inserts (4 mm inner diameter). Such a lab-scale setup allows running six experiments in parallel, under equal feed composition, reaction temperature, and conditions of separation and analysis equipment. It permits separate collection of wax and liquid samples (from each flow line), allowing operation with highmore » productivities of C5+ hydrocarbons. The latter is crucial for a complete understanding of FTS product compositions and will represent an advantage over high-throughput setups with more than ten flows where such instrumental considerations lead to elevated equipment volume, cost, and operation complexity. The identical performance (of the six flows) under similar reaction conditions was assured by testing a same catalyst batch, loaded in all microreactors.« less

Development of a remote laser-induced breakdown spectroscopy system for investigation of calcified tissue samples

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hrdlicka, Ales; Prokes, Lubomir; Stankova, Alice

2010-05-01

The development of a remote laser-induced breakdown spectroscopy (LIBS) setup with an off-axis Newtonian collection optics, Galilean-based focusing telescope, and a 532 nm flattop laser beam source is presented. The device was tested at a 6 m distance on a slice of bone to simulate its possible use in the field, e.g., during archaeological excavations. It is shown that this setup is sufficiently sensitive to both major (P, Mg) and minor elements (Na, Zn, Sr). The measured quantities of Mg, Zn, and Sr correspond to the values obtained by reference laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) measurements within an approximatelymore » 20% range of uncertainty. A single point calibration was performed by use of a bone meal standard . The radial element distribution is almost invariable by use of LA-ICP-MS, whereas the LIBS measurement showed a strong dependence on the sample porosity. Based on these results, this remote LIBS setup with a relatively large (350 mm) collecting mirror is capable of semiquantitative analysis at the level of units of mg kg{sup -1}.« less

Development of an experimental setup for testing the properties of γ/γ' superalloys

NASA Astrophysics Data System (ADS)

Christophe, Siret; Bernard, Viguier; Claude, Salabura Jean; Eric, Andrieu; Sandrine, Lesterlin

2010-07-01

Certification tests on turboshaft engines for helicopters can expose components as high pressure turbine blades to very high temperature during short time periods. To simulate these complex temperature and mechanical stress loadings and to study dimensional and microstructural stability under severe testing conditions, an experimental set-up has been recently developed. In this paper, we first present this new device and describe its performances. Then, the device is used to study the effect of heating procedure on creep results at 1200°C and rafting during primary creep on the single crystal nickel-based superalloy MC2.

Impact of heavy soiling on the power output of PV modules

NASA Astrophysics Data System (ADS)

Schill, Christian; Brachmann, Stefan; Heck, Markus; Weiss, Karl-Anders; Koehl, Michael

2011-09-01

Fraunhofer ISE is running a PV-module outdoor testing set-up on the Gran Canaria island, one of the Canary Island located west of Morroco in the Atlantic Ocean. The performance of the modules is assessed by IV-curve monitoring every 10 minutes. The electronic set-up of the monitoring system - consisting of individual electronic loads for each module which go into an MPP-tracking mode between the IV-measurements - will be described in detail. Soiling of the exposed modules happened because of building constructions nearby. We decided not to clean the modules, but the radiation sensors and recorded the decrease of the power output and the efficiency over time. The efficiency dropped to 20 % within 5 months before a heavy rain and subsequently the service personnel on site cleaned the modules. A smaller rain-fall in between washed the dust partly away and accumulated it at the lower part of the module, what could be concluded from the shape of the IV-curves, which were similar to partial shading by hot-spot-tests and by partial snow cover.

Time-Motion Analysis of Four Automated Systems for the Detection of Chlamydia trachomatis and Neisseria gonorrhoeae by Nucleic Acid Amplification Testing.

PubMed

Williams, James A; Eddleman, Laura; Pantone, Amy; Martinez, Regina; Young, Stephen; Van Der Pol, Barbara

2014-08-01

Next-generation diagnostics for Chlamydia trachomatis and Neisseria gonorrhoeae are available on semi- or fully-automated platforms. These systems require less hands-on time than older platforms and are user friendly. Four automated systems, the ABBOTT m2000 system, Becton Dickinson Viper System with XTR Technology, Gen-Probe Tigris DTS system, and Roche cobas 4800 system, were evaluated for total run time, hands-on time, and walk-away time. All of the systems evaluated in this time-motion study were able to complete a diagnostic test run within an 8-h work shift, instrument setup and operation were straightforward and uncomplicated, and walk-away time ranged from approximately 90 to 270 min in a head-to-head comparison of each system. All of the automated systems provide technical staff with increased time to perform other tasks during the run, offer easy expansion of the diagnostic test menu, and have the ability to increase specimen throughput. © 2013 Society for Laboratory Automation and Screening.

System Integration and In Vivo Testing of a Robot for Ultrasound Guidance and Monitoring During Radiotherapy.

PubMed

Sen, Hasan Tutkun; Bell, Muyinatu A Lediju; Zhang, Yin; Ding, Kai; Boctor, Emad; Wong, John; Iordachita, Iulian; Kazanzides, Peter

2017-07-01

We are developing a cooperatively controlled robot system for image-guided radiation therapy (IGRT) in which a clinician and robot share control of a 3-D ultrasound (US) probe. IGRT involves two main steps: 1) planning/simulation and 2) treatment delivery. The goals of the system are to provide guidance for patient setup and real-time target monitoring during fractionated radiotherapy of soft tissue targets, especially in the upper abdomen. To compensate for soft tissue deformations created by the probe, we present a novel workflow where the robot holds the US probe on the patient during acquisition of the planning computerized tomography image, thereby ensuring that planning is performed on the deformed tissue. The robot system introduces constraints (virtual fixtures) to help to produce consistent soft tissue deformation between simulation and treatment days, based on the robot position, contact force, and reference US image recorded during simulation. This paper presents the system integration and the proposed clinical workflow, validated by an in vivo canine study. The results show that the virtual fixtures enable the clinician to deviate from the recorded position to better reproduce the reference US image, which correlates with more consistent soft tissue deformation and the possibility for more accurate patient setup and radiation delivery.

Surgical treatment of gastroesophageal reflux disease and upside-down stomach using the Da Vinci robotic system. A prospective study.

PubMed

Hartmann, Jens; Jacobi, Christoph A; Menenakos, Charalambos; Ismail, Mahmoud; Braumann, Chris

2008-03-01

So far, the impact of telematic surgical approach in Gastroesophageal Reflux Disease (GERD) is still obscure. In this prospective study, we analyzed the Da Vinci Intuitive Surgical robotic system for antireflux surgery. In April 2003, we set up a pilot study to evaluate the efficacy of laparoscopic telerobotic surgery using the three-arm Da Vinci system. Optimal trocar positions, operating and setup times, conversion rate, intraoperative complications, and perioperative morbidity, as well as mortality rate, were analyzed. The median age was 53 years (range 25-74) in 118 patients (52 female/66 male). In 17 patients, an upside-down stomach- and in 101 GERD was surgical indication. The median operating time has been reduced from 105 min to 91 min after 40 procedures and setup time from 24.5 min to 10.4 min after 10 procedures. The system is safe and it seems to be superior to traditional laparoscopy during dissection in the esophageal hiatus region. This compensates long setup- and operating times. Disadvantages are the high costs, the time to master the setup/system and the necessity of exact trocar positioning.

Assay of Ca2+ transport by VDAC1 reconstituted into liposomes.

PubMed

Ben-Hail, Danya; Shoshan-Barmatz, Varda

2014-02-01

Ca(2+) permeability mediated by voltage-dependent anion-selective channel protein 1 (VDAC1) can be tested by reconstitution of purified VDAC1 into liposomes. Here, we describe a setup for this membranal system, which has been used to study the transport activity of various transporters, including VDAC1, and allows detection of the passage of molecules across the lipid bilayer. Despite the disadvantage of needing radiolabeled molecules, this system is highly desirable when the transport properties of noncharged molecules and/or active transporters are studied.

Water tunnel flow visualization using a laser

NASA Technical Reports Server (NTRS)

Beckner, C.; Curry, R. E.

1985-01-01

Laser systems for flow visualization in water tunnels (similar to the vapor screen technique used in wind tunnels) can provide two-dimensional cross-sectional views of complex flow fields. This parametric study documents the practical application of the laser-enhanced visualization (LEV) technique to water tunnel testing. Aspects of the study include laser power levels, flow seeding (using flourescent dyes and embedded particulates), model preparation, and photographic techniques. The results of this study are discussed to provide potential users with basic information to aid in the design and setup of an LEV system.

Coupling scanning tunneling microscope and supersonic molecular beams: a unique tool for in situ investigation of the morphology of activated systems.

PubMed

Smerieri, M; Reichelt, R; Savio, L; Vattuone, L; Rocca, M

2012-09-01

We report here on a new experimental apparatus combining a commercial low temperature scanning tunneling microscope with a supersonic molecular beam. This setup provides a unique tool for the in situ investigation of the topography of activated adsorption systems and opens thus new interesting perspectives. It has been tested towards the formation of the O/Ag(110) added rows reconstruction and of their hydroxylation, comparing data recorded upon O(2) exposure at thermal and hyperthermal energies.

Effect of vertical active vibration isolation on tracking performance and on ride qualities

NASA Technical Reports Server (NTRS)

Dimasi, F. P.; Allen, R. E.; Calcaterra, P. C.

1972-01-01

An investigation to determine the effect on pilot performance and comfort of an active vibration isolation system for a commercial transport pilot seat is reported. The test setup consisted of: a hydraulic shaker which produced random vertical vibration inputs; the active vibration isolation system; the pilot seat; the pilot control wheel and column; the side-arm controller; and a two-axis compensatory tracking task. The effects of various degrees of pilot isolation on short-term (two-minute) tracking performance and comfort were determined.

Test measurement on ion-molecule reactions in a ringelectrode ion trap

NASA Astrophysics Data System (ADS)

Savic, I.; Lukic, S. R.; Guth, I.; Gerlich, D.

2006-05-01

Very recently a new experimental setup has been developed allowing studies of astrophysically relevant collisions between neutral atoms and small pure carbon molecules from one side and ions from the other side and first results are obtained (Savić et al., 2005). The ions are stored in a radio- frequency (rf) ring-electrode trap and during reaction time exposed to the effusive carbon beam. In this paper, one of the final tests of the experimental setup is presented.

Setup for irradiation and characterization of materials and Si particle detectors at cryogenic temperatures

NASA Astrophysics Data System (ADS)

Väyrynen, S.; Pusa, P.; Sane, P.; Tikkanen, P.; Räisänen, J.; Kuitunen, K.; Tuomisto, F.; Härkönen, J.; Kassamakov, I.; Tuominen, E.; Tuovinen, E.

2007-03-01

A novel facility for proton irradiation with sample cryocooling has been developed at the Accelerator Laboratory of Helsinki University (equipped with a 5 MV tandem accelerator). The setup enables unique experiments to be carried out within the temperature range of 10-300 K. The setup has been constructed for "on-line" studies of vacancies with positron annihilation spectroscopy (PAS) including the option for optical ionization of the vacancies, and for current-voltage ( IV) measurements of irradiated silicon particle detectors. The setup is described in detail and typical performance characteristics are provided. The facility functionality was tested by performing PAS experiments with high-resistivity silicon and by IV measurements for two types of irradiated silicon particle detectors.

The reliability and validity of a designed setup for the assessment of static back extensor force and endurance in older women with and without hyperkyphosis.

PubMed

Roghani, Taybeh; Khalkhali Zavieh, Minoo; Rahimi, Abbas; Talebian, Saeed; Manshadi, Farideh Dehghan; Akbarzadeh Baghban, Alireza; King, Nicole; Katzman, Wendy

2018-01-25

The purpose of this study was to investigate the intra-rater reliability and validity of a designed load cell setup for the measurement of back extensor muscle force and endurance. The study sample included 19 older women with hyperkyphosis, mean age 67.0 ± 5.0 years, and 14 older women without hyperkyphosis, mean age 63.0 ± 6.0 years. Maximum back extensor force and endurance were measured in a sitting position with a designed load cell setup. Tests were performed by the same examiner on two separate days within a 72-hour interval. The intra-rater reliability of the measurements was analyzed using intraclass correlation coefficient (ICC), standard errors of measurement (SEM), and minimal detectable change (MDC). The validity of the setup was determined using Pearson correlation analysis and independent t-test. Using our designed load cell, the values of ICC indicated very high reliability of force measurement (hyperkyphosis group: 0.96, normal group: 0.97) and high reliability of endurance measurement (hyperkyphosis group: 0.82, normal group: 0.89). For all tests, the values of SEM and MDC were low in both groups. A significant correlation between two documented forces (load cell force and target force) and significant differences in the muscle force and endurance among the two groups were found. The measurements of static back muscle force and endurance are reliable and valid with our designed setup in older women with and without hyperkyphosis.

Active damping of the e-p instability at the Los Alamos Proton Storage Ring

NASA Astrophysics Data System (ADS)

Macek, R. J.; Assadi, S.; Byrd, J. M.; Deibele, C. E.; Henderson, S. D.; Lee, S. Y.; McCrady, R. C.; Pivi, M. F. T.; Plum, M. A.; Walbridge, S. B.; Zaugg, T. J.

2007-12-01

A prototype of an analog, transverse (vertical) feedback system for active damping of the two-stream (e-p) instability has been developed and successfully tested at the Los Alamos Proton Storage Ring (PSR). This system was able to improve the instability threshold by approximately 30% (as measured by the change in RF buncher voltage at instability threshold). The feedback system configuration, setup procedures, and optimization of performance are described. Results of several experimental tests of system performance are presented including observations of instability threshold improvement and grow-damp experiments, which yield estimates of instability growth and damping rates. A major effort was undertaken to identify and study several factors limiting system performance. Evidence obtained from these tests suggests that performance of the prototype was limited by higher instability growth rates arising from beam leakage into the gap at lower RF buncher voltage and the onset of instability in the horizontal plane, which had no feedback.

Overview of Heat Addition and Efficiency Predictions for an Advanced Stirling Convertor

NASA Technical Reports Server (NTRS)

Wilson, Scott D.; Reid, Terry V.; Schifer, Nicholas A.; Briggs, Maxwell H.

2012-01-01

The U.S. Department of Energy (DOE) and Lockheed Martin Space Systems Company (LMSSC) have been developing the Advanced Stirling Radioisotope Generator (ASRG) for use as a power system for space science missions. This generator would use two high-efficiency Advanced Stirling Convertors (ASCs), developed by Sunpower Inc. and NASA Glenn Research Center (GRC). The ASCs convert thermal energy from a radioisotope heat source into electricity. As part of ground testing of these ASCs, different operating conditions are used to simulate expected mission conditions. These conditions require achieving a particular operating frequency, hot end and cold end temperatures, and specified electrical power output for a given net heat input. Microporous bulk insulation is used in the ground support test hardware to minimize the loss of thermal energy from the electric heat source to the environment. The insulation package is characterized before operation to predict how much heat will be absorbed by the convertor and how much will be lost to the environment during operation. In an effort to validate these predictions, numerous tasks have been performed, which provided a more accurate value for net heat input into the ASCs. This test and modeling effort included: (a) making thermophysical property measurements of test setup materials to provide inputs to the numerical models, (b) acquiring additional test data that was collected during convertor tests to provide numerical models with temperature profiles of the test setup via thermocouple and infrared measurements, (c) using multidimensional numerical models (computational fluid dynamics code) to predict net heat input of an operating convertor, and (d) using validation test hardware to provide direct comparison of numerical results and validate the multidimensional numerical models used to predict convertor net heat input. This effort produced high fidelity ASC net heat input predictions, which were successfully validated using specially designed test hardware enabling measurement of heat transferred through a simulated Stirling cycle. The overall effort and results are discussed.

Electrostatic Positioning System for a free fall test at drop tower Bremen and an overview of tests for the Weak Equivalence Principle in past, present and future

NASA Astrophysics Data System (ADS)

Sondag, Andrea; Dittus, Hansjörg

2016-08-01

The Weak Equivalence Principle (WEP) is at the basis of General Relativity - the best theory for gravitation today. It has been and still is tested with different methods and accuracies. In this paper an overview of tests of the Weak Equivalence Principle done in the past, developed in the present and planned for the future is given. The best result up to now is derived from the data of torsion balance experiments by Schlamminger et al. (2008). An intuitive test of the WEP consists of the comparison of the accelerations of two free falling test masses of different composition. This has been carried through by Kuroda & Mio (1989, 1990) with the up to date most precise result for this setup. There is still more potential in this method, especially with a longer free fall time and sensors with a higher resolution. Providing a free fall time of 4.74 s (9.3 s using the catapult) the drop tower of the Center of Applied Space Technology and Microgravity (ZARM) at the University of Bremen is a perfect facility for further improvements. In 2001 a free fall experiment with high sensitive SQUID (Superconductive QUantum Interference Device) sensors tested the WEP with an accuracy of 10-7 (Nietzsche, 2001). For optimal conditions one could reach an accuracy of 10-13 with this setup (Vodel et al., 2001). A description of this experiment and its results is given in the next part of this paper. For the free fall of macroscopic test masses it is important to start with precisely defined starting conditions concerning the positions and velocities of the test masses. An Electrostatic Positioning System (EPS) has been developed to this purpose. It is described in the last part of this paper.

Reducing tilt-to-length coupling for the LISA test mass interferometer

NASA Astrophysics Data System (ADS)

Tröbs, M.; Schuster, S.; Lieser, M.; Zwetz, M.; Chwalla, M.; Danzmann, K.; Fernández Barránco, G.; Fitzsimons, E. D.; Gerberding, O.; Heinzel, G.; Killow, C. J.; Perreur-Lloyd, M.; Robertson, D. I.; Schwarze, T. S.; Wanner, G.; Ward, H.

2018-05-01

Objects sensed by laser interferometers are usually not stable in position or orientation. This angular instability can lead to a coupling of angular tilt to apparent longitudinal displacement—tilt-to-length coupling (TTL). In LISA this is a potential noise source for both the test mass interferometer and the long-arm interferometer. We have experimentally investigated TTL coupling in a setup representative for the LISA test mass interferometer and used this system to characterise two different imaging systems (a two-lens design and a four-lens design) both designed to minimise TTL coupling. We show that both imaging systems meet the LISA requirement of  ±25 μm rad‑1 for interfering beams with relative angles of up to  ±300 μrad. Furthermore, we found a dependency of the TTL coupling on beam properties such as the waist size and location, which we characterised both theoretically and experimentally.

DPM — efficient storage in diverse environments

NASA Astrophysics Data System (ADS)

Hellmich, Martin; Furano, Fabrizio; Smith, David; Brito da Rocha, Ricardo; Álvarez Ayllón, Alejandro; Manzi, Andrea; Keeble, Oliver; Calvet, Ivan; Regala, Miguel Antonio

2014-06-01

Recent developments, including low power devices, cluster file systems and cloud storage, represent an explosion in the possibilities for deploying and managing grid storage. In this paper we present how different technologies can be leveraged to build a storage service with differing cost, power, performance, scalability and reliability profiles, using the popular storage solution Disk Pool Manager (DPM/dmlite) as the enabling technology. The storage manager DPM is designed for these new environments, allowing users to scale up and down as they need it, and optimizing their computing centers energy efficiency and costs. DPM runs on high-performance machines, profiting from multi-core and multi-CPU setups. It supports separating the database from the metadata server, the head node, largely reducing its hard disk requirements. Since version 1.8.6, DPM is released in EPEL and Fedora, simplifying distribution and maintenance, but also supporting the ARM architecture beside i386 and x86_64, allowing it to run the smallest low-power machines such as the Raspberry Pi or the CuBox. This usage is facilitated by the possibility to scale horizontally using a main database and a distributed memcached-powered namespace cache. Additionally, DPM supports a variety of storage pools in the backend, most importantly HDFS, S3-enabled storage, and cluster file systems, allowing users to fit their DPM installation exactly to their needs. In this paper, we investigate the power-efficiency and total cost of ownership of various DPM configurations. We develop metrics to evaluate the expected performance of a setup both in terms of namespace and disk access considering the overall cost including equipment, power consumptions, or data/storage fees. The setups tested range from the lowest scale using Raspberry Pis with only 700MHz single cores and a 100Mbps network connections, over conventional multi-core servers to typical virtual machine instances in cloud settings. We evaluate the combinations of different name server setups, for example load-balanced clusters, with different storage setups, from using a classic local configuration to private and public clouds.

[EC5-Space Suit Assembly Team- Internship

NASA Technical Reports Server (NTRS)

Maicke, Andrew

2016-01-01

There were three main projects in this internship. The first pertained to the Bearing Dust Cycle Test, in particular automating the test to allow for easier administration. The second concerned modifying the communication system setup in the Z2 suit, where speakers and mics were adjusted to allow for more space in the helmet. And finally, the last project concerned the tensile strength testing of fabrics deemed as candidates for space suit materials and desired to be sent off for radiation testing. The major duties here are split up between the major projects detailed above. For the Bearing Dust Cycle Test, the first objective was to find a way to automate administration of the test, as the previous version was long and tedious to perform. In order to do this, it was necessary to introduce additional electronics and perform programming to control the automation. Once this was done, it would be necessary to update documents concerning the test setup, procedure, and potential hazards. Finally, I was tasked with running tests using the new system to confirm system performance. For the Z2 communication system modifications, it was necessary to investigate alternative speakers and microphones which may have better performance than those currently used in the suit. Further, new speaker and microphone positions needed to be identified to keep them out of the way of the suit user. Once this was done, appropriate hardware (such as speaker or microphone cases and holders) could be prototyped and fabricated. For the suit material strength testing, the first task was to gather and document various test fabrics to identify the best suit material candidates. Then, it was needed to prepare samples for testing to establish baseline measurements and specify a testing procedure. Once the data was fully collected, additional test samples would be prepared and sent off-site to undergo irradiation before being tested again to observe changes in strength performance. For the Bearing Dust Cycle Test, automation was achieved through use of a servo motor and code written in LabVIEW. With this a small electrical servo controller was constructed and added to the system. For the Z2 communication modifications speaker cases were developed and printed, and new speakers and mics were selected. This allowed us to move the speakers and mics to locations to remain out of the suit users way. For the suit material strength testing, five material candidates were identified and test samples were created. These samples underwent testing, and baseline test results were gathered, though these results are currently being investigated for accuracy. The main process efficiency developed during the course of this internship comes from automation of the Bearing Dust Cycle Test. In particular, many hours of human involvement and precise operation are replaced with a simple motor setup. Thus it is no longer required to man the test, saving valuable employee time. This internship has confirmed a few things for me, namely that I both want to work as an engineer for an aerospace firm and that in particular I want to work for the Johnson Space Center. I am also confirmed in my desire to work with electronics, though I was surprised to enjoy prototyping 3D CAD design as much as I did. Therefore, I will make an effort to build my skills in this area so that I can continue to design mechanical models. In fact, I found the process of hands-on prototyping to be perhaps the most fun aspect of my time working here. This internship has also furthered my excitement for continual education, and I will hopefully be pursuing a masters in my field in the near future.

Develop and test fuel cell powered on-site integrated total energy systems. Phase 3: Full-scale power plant development

NASA Technical Reports Server (NTRS)

Kaufman, A.; Pudick, S.; Wang, C. L.; Werth, J.; Whelan, J. A.

1984-01-01

Two 25-cell, 13 inch x 23 inch (4kW) stacks were started up to evaluate the reliability of component and stack technology developed through the end of 1983. Both stacks started up well and are running satisfactorily on hydrogen-air after 1900 hours and 800 hours, respectively. A synthetic-reformat mixing station is nearing completion, and both stacks will be operated on reformate fuel. A stack-protection control system was placed in operation for Stack No. 2, and a similar set-up is in preparation for Stack No. 1. This system serves to change operating conditions or shut the stack down to avoid deleterious effects from nonstack-related upsets. The capability will greatly improve changes of obtaining meaningful long-term test data.

Mobile CARS - IRS Instrument for Simultaneous Spectroscopic Measurement of Multiple Properties in Gaseous Flows

NASA Technical Reports Server (NTRS)

Bivolaru, Daniel; Lee, Joseph W.; Jones, Stephen B.; Tedder, Sarah A.; Danehy, Paul M.; Weikl, M. C.; Magnotti, G.; Cutler, Andrew D.

2007-01-01

This paper describes a measurement system based on the dual-pump coherent anti-Stokes Raman spectroscopy (CARS) and interferometric Rayleigh scattering (IRS) methods. The IRS measurement is performed simultaneously with the CARS measurement using a common green laser beam as a narrow-band light source. The mobile CARS-IRS instrument is designed for the use both in laboratories as well as in ground-based combustion test facilities. Furthermore, it is designed to be easily transported between laboratory and test facility. It performs single-point spatially and temporally resolved simultaneous measurements of temperature, species mole fraction of N2, O2, and H2, and two-components of velocity. A mobile laser system can be placed inside or outside the test facility, while a beam receiving and monitoring system is placed near the measurement location. Measurements in a laboratory small-scale Mach 1.6 H2-air combustion-heated supersonic jet were performed to test the capability of the system. Final setup and pretests of a larger scale reacting jet are ongoing at NASA Langley Research Center s Direct Connect Supersonic Combustor Test Facility (DCSCTF).

Comparative study on novel test systems to determine disintegration time of orodispersible films.

PubMed

Preis, Maren; Gronkowsky, Dorothee; Grytzan, Dominik; Breitkreutz, Jörg

2014-08-01

Orodispersible films (ODFs) are a promising innovative dosage form enabling drug administration without the need for water and minimizing danger of aspiration due to their fast disintegration in small amounts of liquid. This study focuses on the development of a disintegration test system for ODFs. Two systems were developed and investigated: one provides an electronic end-point, and the other shows a transferable setup of the existing disintegration tester for orodispersible tablets. Different ODF preparations were investigated to determine the suitability of the disintegration test systems. The use of different test media and the impact of different storage conditions of ODFs on their disintegration time were additionally investigated. The experiments showed acceptable reproducibility (low deviations within sample replicates due to a clear determination of the measurement end-point). High temperatures and high humidity affected some of the investigated ODFs, resulting in higher disintegration time or even no disintegration within the tested time period. The methods provided clear end-point detection and were applicable for different types of ODFs. By the modification of a conventional test system to enable application for films, a standard method could be presented to ensure uniformity in current quality control settings. © 2014 Royal Pharmaceutical Society.

Impact Testing of a Stirling Converter's Linear Alternator

NASA Technical Reports Server (NTRS)

Suarez, Vicente J.; Goodnight, Thomas W.; Hughes, William O.; Samorezov, Sergey

2002-01-01

The U.S. Department of Energy (DOE), in conjunction with the NASA John H. Glenn Research Center and Stirling Technology Company, are currently developing a Stirling convertor for a Stirling Radioisotope Generator (SRG). NASA Headquarters and DOE have identified the SRG for potential use as an advanced spacecraft power system for future NASA deep-space and Mars surface missions. Low-level dynamic impact tests were conducted at NASA Glenn Research Center's Structural Dynamics Laboratory as part of the development of this technology. The purpose of this test was to identify dynamic structural characteristics of the Stirling Technology Demonstration Convertor (TDC). This paper addresses the test setup, procedure, and results of the impact testing conducted on the Stirling TDC in May 2001.

Impact testing of a Stirling convertor's linear alternator

NASA Astrophysics Data System (ADS)

Suárez, Vicente J.; Goodnight, Thomas W.; Hughes, William O.; Samorezov, Sergey

2002-01-01

The U.S. Department of Energy (DOE), in conjunction with NASA John H. Glenn Research Center and Stirling Technology Company, are currently developing a Stirling convertor for a Stirling Radioisotope Generator (SRG). NASA Headquarters and DOE have identified the SRG for potential use as an advanced spacecraft power system for future NASA deep-space and Mars surface missions. Low-level dynamic impact tests were conducted at NASA Glenn Research Center's Structural Dynamics Laboratory as part of the development of this technology. The purpose of this test was to identify dynamic structural characteristics of the Stirling Technology Demonstration Convertor (TDC). This paper addresses the test setup, procedure and results of the impact testing conducted on the Stirling TDC in May 2001. .

A simultaneous multimodal imaging system for tissue functional parameters

NASA Astrophysics Data System (ADS)

Ren, Wenqi; Zhang, Zhiwu; Wu, Qiang; Zhang, Shiwu; Xu, Ronald

2014-02-01

Simultaneous and quantitative assessment of skin functional characteristics in different modalities will facilitate diagnosis and therapy in many clinical applications such as wound healing. However, many existing clinical practices and multimodal imaging systems are subjective, qualitative, sequential for multimodal data collection, and need co-registration between different modalities. To overcome these limitations, we developed a multimodal imaging system for quantitative, non-invasive, and simultaneous imaging of cutaneous tissue oxygenation and blood perfusion parameters. The imaging system integrated multispectral and laser speckle imaging technologies into one experimental setup. A Labview interface was developed for equipment control, synchronization, and image acquisition. Advanced algorithms based on a wide gap second derivative reflectometry and laser speckle contrast analysis (LASCA) were developed for accurate reconstruction of tissue oxygenation and blood perfusion respectively. Quantitative calibration experiments and a new style of skinsimulating phantom were designed to verify the accuracy and reliability of the imaging system. The experimental results were compared with a Moor tissue oxygenation and perfusion monitor. For In vivo testing, a post-occlusion reactive hyperemia (PORH) procedure in human subject and an ongoing wound healing monitoring experiment using dorsal skinfold chamber models were conducted to validate the usability of our system for dynamic detection of oxygenation and perfusion parameters. In this study, we have not only setup an advanced multimodal imaging system for cutaneous tissue oxygenation and perfusion parameters but also elucidated its potential for wound healing assessment in clinical practice.

Proportional and Integral Thermal Control System for Large Scale Heating Tests

NASA Technical Reports Server (NTRS)

Fleischer, Van Tran

2015-01-01

The National Aeronautics and Space Administration Armstrong Flight Research Center (Edwards, California) Flight Loads Laboratory is a unique national laboratory that supports thermal, mechanical, thermal/mechanical, and structural dynamics research and testing. A Proportional Integral thermal control system was designed and implemented to support thermal tests. A thermal control algorithm supporting a quartz lamp heater was developed based on the Proportional Integral control concept and a linearized heating process. The thermal control equations were derived and expressed in terms of power levels, integral gain, proportional gain, and differences between thermal setpoints and skin temperatures. Besides the derived equations, user's predefined thermal test information generated in the form of thermal maps was used to implement the thermal control system capabilities. Graphite heater closed-loop thermal control and graphite heater open-loop power level were added later to fulfill the demand for higher temperature tests. Verification and validation tests were performed to ensure that the thermal control system requirements were achieved. This thermal control system has successfully supported many milestone thermal and thermal/mechanical tests for almost a decade with temperatures ranging from 50 F to 3000 F and temperature rise rates from -10 F/s to 70 F/s for a variety of test articles having unique thermal profiles and test setups.

A set-up for simultaneous measurement of second harmonic generation and streaming potential and some test applications.

PubMed

Lützenkirchen, Johannes; Scharnweber, Tim; Ho, Tuan; Striolo, Alberto; Sulpizi, Marialore; Abdelmonem, Ahmed

2018-06-15

We present a measurement cell that allows simultaneous measurement of second harmonic generation (SHG) and streaming potential (SP) at mineral-water interfaces with flat specimen that are suitable for non-linear optical (NLO) studies. The set-up directly yields SHG data for the interface of interest and can also be used to obtain information concerning the influence of flow on NLO signals from that interface. The streaming potential is at present measured against a reference substrate (PTFE). The properties of this inert reference can be independently determined for the same conditions. With the new cell, for the first time the SHG signal and the SP for flat surfaces have been simultaneously measured on the same surface. This can in turn be used to unambiguously relate the two observations for identical solution composition. The SHG test of the cell with a fluorite sample confirmed previously observed differences in NLO signal under flow vs. no flow conditions in sum frequency generation (SFG) investigations. As a second test surface, an inert ("hydrophobic") OTS covered sapphire-c electrolyte interface was studied to verify the zeta-potential measurements with the new cell. For this system we obtained combined zeta-potential/SHG data in the vicinity of the point of zero charge, which were found to be proportional to each other as expected. Furthermore, on the accessible time scales of the SHG measurements no effects of flow, flow velocity and stopped flow occurred on the interfacial water structure. This insensitivity to flow for the inert surface was corroborated by concomitant molecular dynamics simulations. Finally, the set-up was used for simultaneous measurements of the two properties as a function of pH in automated titrations with an oxidic surface. Different polarization combinations obtained in two separate titrations, yielded clearly different SHG data, while under identical conditions zeta-potentials were exactly reproduced. The polarization combination that is characteristic for dipoles perpendicular to the surface scaled with the zeta-potentials over the pH-range studied, while the other did not. The work provides an advanced approach for investigating liquid/surface interactions which play a major role in our environment. The set-up can be upgraded for SFG studies, which will allow more detailed studies on the chemistry and the water structure at a given interface, but also the combined study of specific adsorption including kinetics in combination with electrokinetics. Such investigations are crucial for the basic understanding of many environmental processes from aquatic to atmospheric systems. Copyright © 2018 Elsevier Inc. All rights reserved.

[Comparison of four identical electronic noses and three measurement set-ups].

PubMed

Koczulla, R; Hattesohl, A; Biller, H; Hofbauer, J; Hohlfeld, J; Oeser, C; Wirtz, H; Jörres, R A

2011-08-01

Volatile organic compounds (VOCs) can be used as biomarkers in exhaled air. VOC profiles can be detected by an array of nanosensors of an electronic nose. These profiles can be analysed using bioinformatics. It is, however, not known whether different devices of the same model measure identically and to which extent different set-ups and the humidity of the inhaled air influence the VOC profile. Three different measuring set-ups were designed and three healthy control subjects were measured with each of them, using four devices of the same model (Cyranose 320™, Smiths Detection). The exhaled air was collected in a plastic bag. Either ambient air was used as reference (set-up Leipzig), or the reference air was humidified (100% relative humidity) (set-up Marburg and set-up Munich). In the set-up Marburg the subjects inhaled standardised medical air (Aer medicinalis Linde, AGA AB) out of a compressed air bottle through a demand valve; this air (after humidification) was also used as reference. In the set-up Leipzig the subjects inhaled VOC-filtered ambient air, in the set-up Munich unfiltered room air. The data were evaluated using either the real-time data or the changes in resistance as calculated by the device. The results were clearly dependent on the set-up. Apparently, humidification of the reference air could reduce the variance between devices, but this result was also dependent on the evaluation method used. When comparing the three subjects, the set-ups Munich and Marburg mapped these in a similar way, whereas not only the signals but also the variance of the set-up Leipzig were larger. Measuring VOCs with an electronic nose has not yet been standardised and the set-up significantly affects the results. As other researchers use further methods, it is currently not possible to draw generally accepted conclusions. More systematic tests are required to find the most sensitive and reliable but still feasible set-up so that comparability is improved. © Georg Thieme Verlag KG Stuttgart · New York.

An automatic dose verification system for adaptive radiotherapy for helical tomotherapy

NASA Astrophysics Data System (ADS)

Mo, Xiaohu; Chen, Mingli; Parnell, Donald; Olivera, Gustavo; Galmarini, Daniel; Lu, Weiguo

2014-03-01

Purpose: During a typical 5-7 week treatment of external beam radiotherapy, there are potential differences between planned patient's anatomy and positioning, such as patient weight loss, or treatment setup. The discrepancies between planned and delivered doses resulting from these differences could be significant, especially in IMRT where dose distributions tightly conforms to target volumes while avoiding organs-at-risk. We developed an automatic system to monitor delivered dose using daily imaging. Methods: For each treatment, a merged image is generated by registering the daily pre-treatment setup image and planning CT using treatment position information extracted from the Tomotherapy archive. The treatment dose is then computed on this merged image using our in-house convolution-superposition based dose calculator implemented on GPU. The deformation field between merged and planning CT is computed using the Morphon algorithm. The planning structures and treatment doses are subsequently warped for analysis and dose accumulation. All results are saved in DICOM format with private tags and organized in a database. Due to the overwhelming amount of information generated, a customizable tolerance system is used to flag potential treatment errors or significant anatomical changes. A web-based system and a DICOM-RT viewer were developed for reporting and reviewing the results. Results: More than 30 patients were analysed retrospectively. Our in-house dose calculator passed 97% gamma test evaluated with 2% dose difference and 2mm distance-to-agreement compared with Tomotherapy calculated dose, which is considered sufficient for adaptive radiotherapy purposes. Evaluation of the deformable registration through visual inspection showed acceptable and consistent results, except for cases with large or unrealistic deformation. Our automatic flagging system was able to catch significant patient setup errors or anatomical changes. Conclusions: We developed an automatic dose verification system that quantifies treatment doses, and provides necessary information for adaptive planning without impeding clinical workflows.

Wireless Data-Acquisition System for Testing Rocket Engines

NASA Technical Reports Server (NTRS)

Lin, Chujen; Lonske, Ben; Hou, Yalin; Xu, Yingjiu; Gang, Mei

2007-01-01

A prototype wireless data-acquisition system has been developed as a potential replacement for a wired data-acquisition system heretofore used in testing rocket engines. The traditional use of wires to connect sensors, signal-conditioning circuits, and data acquisition circuitry is time-consuming and prone to error, especially when, as is often the case, many sensors are used in a test. The system includes one master and multiple slave nodes. The master node communicates with a computer via an Ethernet connection. The slave nodes are powered by rechargeable batteries and are packaged in weatherproof enclosures. The master unit and each of the slave units are equipped with a time-modulated ultra-wide-band (TMUWB) radio transceiver, which spreads its RF energy over several gigahertz by transmitting extremely low-power and super-narrow pulses. In this prototype system, each slave node can be connected to as many as six sensors: two sensors can be connected directly to analog-to-digital converters (ADCs) in the slave node and four sensors can be connected indirectly to the ADCs via signal conditioners. The maximum sampling rate for streaming data from any given sensor is about 5 kHz. The bandwidth of one channel of the TM-UWB radio communication system is sufficient to accommodate streaming of data from five slave nodes when they are fully loaded with data collected through all possible sensor connections. TM-UWB radios have a much higher spatial capacity than traditional sinusoidal wave-based radios. Hence, this TM-UWB wireless data-acquisition can be scaled to cover denser sensor setups for rocket engine test stands. Another advantage of TM-UWB radios is that it will not interfere with existing wireless transmission. The maximum radio-communication range between the master node and a slave node for this prototype system is about 50 ft (15 m) when the master and slave transceivers are equipped with small dipole antennas. The range can be increased by changing to larger antennas and/or greater transmission power. The battery life of a slave node ranges from about six hours during operation at full capacity to as long as three days when the system is in a "sleep" mode used to conserve battery charge during times between setup and rocket-engine testing. Batteries can be added to prolong operational lifetimes. The radio transceiver dominates the power consumption.

SU-E-J-55: End-To-End Effectiveness Analysis of 3D Surface Image Guided Voluntary Breath-Holding Radiotherapy for Left Breast

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, M; Feigenberg, S

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 patientmore » 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.« less

Liquid helium-free cryostat and hermetically sealed cryogenic microwave cavity for hyperfine spectroscopy of antiprotonic helium

PubMed Central

Massiczek, O.; Friedreich, S.; Juhász, B.; Widmann, E.; Zmeskal, J.

2011-01-01

The design and properties of a new cryogenic set-up for laser–microwave–laser hyperfine structure spectroscopy of antiprotonic helium – an experiment performed at the CERN-Antiproton Decelerator (AD), Geneva, Switzerland – are described. Similar experiments for 4He have been performed at the AD for several years. Due to the usage of a liquid helium operated cryostat and therefore necessary refilling of coolants, a loss of up to 10% beamtime occurred. The decision was made to change the cooling system to a closed-circuit cryocooler. New hermetically sealed target cells with minimised 3He gas volume and different dimensions of the microwave resonator for measuring the 3He transitions were needed. A new set-up has been designed and tested at Stefan Meyer Institute in Vienna before being used for the 2009 and 2010 beamtimes at the AD. PMID:22267883

SED16 autonomous star tracker night sky testing

NASA Astrophysics Data System (ADS)

Foisneau, Thierry; Piriou, Véronique; Perrimon, Nicolas; Jacob, Philippe; Blarre, Ludovic; Vilaire, Didier

2017-11-01

The SED16 is an autonomous multi-missions star tracker which delivers three axis satellite attitude in an inertial reference frame and the satellite angular velocity with no prior information. The qualification process of this star sensor includes five validation steps using optical star simulator, digitized image simulator and a night sky tests setup. The night sky testing was the final step of the qualification process during which all the functions of the star tracker were used in almost nominal conditions : Autonomous Acquisition of the attitude, Autonomous Tracking of ten stars. These tests were performed in Calern in the premises of the OCA (Observatoire de la Cote d'Azur). The test set-up and the test results are described after a brief review of the sensor main characteristics and qualification process.

Detection of fractional solitons in quantum spin Hall systems

NASA Astrophysics Data System (ADS)

Fleckenstein, C.; Traverso Ziani, N.; Trauzettel, B.

2018-03-01

We propose two experimental setups that allow for the implementation and the detection of fractional solitons of the Goldstone-Wilczek type. The first setup is based on two magnetic barriers at the edge of a quantum spin Hall system for generating the fractional soliton. If then a quantum point contact is created with the other edge, the linear conductance shows evidence of the fractional soliton. The second setup consists of a single magnetic barrier covering both edges and implementing a long quantum point contact. In this case, the fractional soliton can unambiguously be detected as a dip in the conductance without the need to control the magnetization of the barrier.

Quality Control of Injection Molded Eyewear by Non-Contact Deflectometry

NASA Astrophysics Data System (ADS)

Speck, A.; Zelzer, B.; Langenbucher, A.; Eppig, T.

2014-07-01

Occupational eye wear such as safety spectacles are manufactured by injection molding techniques. Testing of the assembled safety spectacle lenses in transmission is state of the art, but there is a lack of surface measurement systems for occupational safety lenses. The purpose of this work was to validate a deflectometric setup for topography measurement, detection of defects and visualization of the polishing quality, e.g. casting indentations or impressions, for the production process of safety spectacles. The setup is based on a customized stereo phase measuring deflectometer (PMD), equipped with 3 cameras with f'1,2 = 16 mm and f'3 = 8.5 mm and a specified measurement uncertainty of ± 3 μm. Sixteen plastic lenses and 8 corresponding injection molds from 4 parallel cavities were used for validation of the deflectometer. For comparison an interferometric method and a reference standard (< λ/10 super polished) was used. The accuracy and bias with a spherical safety spectacle sample was below 1 μm, according to DIN ISO 5725-2.2002-12. The repeatability was 2.1 μm and 35.7 μm for a blind radius fit. In conclusion, the PMD technique is an appropriate tool for characterizing occupational safety spectacle and injections mold surfaces. With the presented setup we were able to quantify the surface quality. This can be useful and may optimize the quality of the end product, in addition to standardized measuring systems in transmission.

[The comparative study of specificity of test-systems in diagnostic of HIV-infection on categories of samples of blood serum of pregnant women].

PubMed

Sharipova, I N; Khodak, N M; Puzirev, V F; Burkov, A N; Ulanova, T I

2015-03-01

The detection of false positive serological reactions (FPSR) on HIV-infection under screening examination of pregnant women is an actual problem of practical health care. The original observations testify that under analysis of the same samples of blood serum of pregnant women using screening immune enzyme test-systems of various manufacturers the unmatched data concerning FPSR can be obtained. The purpose of this study was to implement comparative evaluation of specificity of immune enzyme test-systems of three different manufacturers: "DS-IFA-HIV-AGAT-SCREEN" ("Diagnostic Systems"), "Genscreen Ultra HIV Ag-Ab" "Bio Rad" France) and "The CombiBest HIV-1,2 AG/AT" ("Vector-Best" Novosibirsk). The sampling of 440 samples of blood serums of pregnant women from various medical institutions of Nizhnii Novgorod was analyzed. The results of the study demonstrated that FPSR were detected in all test-systems and at that spectrum of samples differed. The identical specificity of compared test-systems amounted to 98.64%. The alternative approach to FPSR to HIV issue under screening examinations of pregnant women was proposed. The proposed mode consisted of consistent application of two test-systems of fourth generation with different format of setup of reaction.

Acoustic flight tests of rotorcraft noise-abatement approaches using local differential GPS guidance

NASA Technical Reports Server (NTRS)

Chen, Robert T. N.; Hindson, William S.; Mueller, Arnold W.

1995-01-01

This paper presents the test design, instrumentation set-up, data acquisition, and the results of an acoustic flight experiment to study how noise due to blade-vortex interaction (BVI) may be alleviated. The flight experiment was conducted using the NASA/Army Rotorcraft Aircrew Systems Concepts Airborne Laboratory (RASCAL) research helicopter. A Local Differential Global Positioning System (LDGPS) was used for precision navigation and cockpit display guidance. A laser-based rotor state measurement system on board the aircraft was used to measure the main rotor tip-path-plane angle-of-attack. Tests were performed at Crows Landing Airfield in northern California with an array of microphones similar to that used in the standard ICAO/FAA noise certification test. The methodology used in the design of a RASCAL-specific, multi-segment, decelerating approach profile for BVI noise abatement is described, and the flight data pertaining to the flight technical errors and the acoustic data for assessing the noise reduction effectiveness are reported.

Terahertz photometers to observe solar flares from space (SOLAR-T project)

NASA Astrophysics Data System (ADS)

Kaufmann, Pierre; Raulin, Jean-Pierre

The space experiment SOLAR-T designed to observe solar flares at THz frequencies was completed. We present the concept, fabrication and performance of a double THz photometers system. An innovative optical setup allows observations of the full solar disk and the detection of small burst transients at the same time. It is the first detecting system conceived to observe solar flare THz emissions on board of stratospheric balloons. The system has been integrated to data acquisition and telemetry modules for this application. SOLAR-T uses two Golay cell detectors preceded by low-pass filters made of rough surface primary mirrors and membranes, 3 and 7 THz band-pass filters, and choppers. Its photometers can detect small solar bursts (tens of solar flux units) with sub second time resolution. One artificial Sun setup was developed to simulate actual observations. Tests comprised the whole system performance, on ambient and low pressure and temperature conditions. It is intended to provide data on the still unrevealed spectral shape of the mysterious THz solar flares emissions. The experiment is planned to be on board of two long-duration stratospheric balloon flights over Antarctica and Russia in 2014-2016. The SOLAR-T development, fabrication and tests has been accomplished by engineering and research teams from Mackenzie, Unicamp and Bernard Lyot Solar Observatory; Propertech Ltda.; Neuron Ltda.; and Samsung, Brazil; Tydex LCC, Russia; CONICET, Argentina; the stratospheric balloon missions will be carried in cooperation with teams from University of California, Berkeley, USA (flight over Antarctica), and Lebedev Physical Institute, Moscow, Russia (flight over Russia).

Development of a reliable experimental set-up for Dover sole larvae Solea solea L. and exploring the possibility of implementing this housing system in a gnotobiotic model.

PubMed

De Swaef, Evelien; Demeestere, Kristof; Boon, Nico; Van den Broeck, Wim; Haesebrouck, Freddy; Decostere, Annemie

2017-12-01

Due to the increasing importance of the aquaculture sector, diversification in the number of cultured species imposes itself. Dover sole Solea solea L. is put forward as an important new aquaculture candidate due to its high market value and high flesh quality. However, as for many other fish species, sole production is hampered by amongst others high susceptibility to diseases and larval mortality, rendering the need for more research in this area. In this respect, in first instance, a housing system for Dover sole larvae was pinpointed by keeping the animals individually in 24-well plates for 26days with good survival rates and initiating metamorphosis. This ensures a standardised and reliable experimental set-up in which the possible death of one larva has no effect on the other larvae, rendering experiments adopting such a system more reproducible. In addition to proving valuable in many other applications, this multi well system constitutes a firm basis to enable the gnotobiotic rearing of larvae, which hitherto is non-existing for Dover sole. In this respect, secondly, a large number of disinfection protocols were tested, making use of widely employed disinfectants as hydrogen peroxide, glutaraldehyde and/or ozone whether or not combined with a mixture of antimicrobial agents for 24h. Although none of the tested protocols was sufficient to reproducibly generate a gnotobiotic model, the combination of glutaraldehyde and hydrogen peroxide resulted in hatchable, bacteria-free eggs in some cases. Copyright © 2017 Elsevier Ltd. All rights reserved.

4He sample probe for combined microwave and dc transport measurements

NASA Astrophysics Data System (ADS)

Dobrovolskiy, Oleksandr V.; Franke, Jörg; Huth, Michael

2015-03-01

Combined microwave and dc electrical transport measurements at low temperatures represent a valuable experimental method in many research areas. In particular, when samples are conventional superconductors, a typical experiment requires a combination of helium temperatures, a wide range of magnetic fields, and the utilization of coaxial lines along with the usual dc wiring. We report on the general design features and the microwave performance of a custom-made low-temperature sample probe, with a measurement bandwidth tested from dc to 20 GHz. Equipped with six coaxial cables, a heater, Hall and temperature sensors, the probe fits into a ⊘32 mm shaft. We present our setup, analyze its microwave performance, and describe two representative experiments enabled by this system. The proposed setup will be essential for a systematic study of the dc and ac response of the vortex dynamics in nanopatterned superconductors subject to combined dc and microwave stimuli. Besides, it will be valuable for the investigation of a broad class of nonlinear stochastic systems where a combination of dc and high-frequency ac driving in a wide temperature range is necessary.

Photonic crystal enhanced silicon cell based thermophotovoltaic systems

DOE PAGES

Yeng, Yi Xiang; Chan, Walker R.; Rinnerbauer, Veronika; ...

2015-01-30

We report the design, optimization, and experimental results of large area commercial silicon solar cell based thermophotovoltaic (TPV) energy conversion systems. Using global non-linear optimization tools, we demonstrate theoretically a maximum radiative heat-to-electricity efficiency of 6.4% and a corresponding output electrical power density of 0.39 W cm⁻² at temperature T = 1660 K when implementing both the optimized two-dimensional (2D) tantalum photonic crystal (PhC) selective emitter, and the optimized 1D tantalum pentoxide – silicon dioxide PhC cold-side selective filter. In addition, we have developed an experimental large area TPV test setup that enables accurate measurement of radiative heat-to-electricity efficiency formore » any emitter-filter-TPV cell combination of interest. In fact, the experimental results match extremely well with predictions of our numerical models. Our experimental setup achieved a maximum output electrical power density of 0.10W cm⁻² and radiative heat-to-electricity efficiency of 1.18% at T = 1380 K using commercial wafer size back-contacted silicon solar cells.« less

A high-resolution frequency variable experimental setup for studying ferrofluids used in magnetic hyperthermia.

PubMed

Mazon, E E; Villa-Martínez, E; Hernández-Sámano, A; Córdova-Fraga, T; Ibarra-Sánchez, J J; Calleja, H A; Leyva Cruz, J A; Barrera, A; Estrada, J C; Paz, J A; Quintero, L H; Cano, M E

2017-08-01

A scanning system for specific absorption rate of ferrofluids with superparamagnetic nanoparticles is presented in this study. The system contains an induction heating device designed and built with a resonant inverter in order to generate magnetic field amplitudes up to 38 mT, over the frequency band 180-525 kHz. Its resonant circuit involves a variable capacitor with 1 nF of capacitance steps to easily select the desired frequency, reaching from 0.3 kHz/nF up to 5 kHz/nF of resolution. The device performance is characterized in order to compare with the theoretical predictions of frequency and amplitude, showing a good agreement with the resonant inverters theory. Additionally, the setup is tested using a synthetic iron oxide with 10 ± 1 nm diameter suspended in liquid glycerol, with concentrations at 1%. Meanwhile, the temperature rise is measured to determine the specific absorption rate and calculate the dissipated power density for each f. This device is a suitable alternative to studying ferrofluids and analyzes the dependence of the power absorption density with the magnetic field intensity and frequency.

Kalman filter based control for Adaptive Optics

NASA Astrophysics Data System (ADS)

Petit, Cyril; Quiros-Pacheco, Fernando; Conan, Jean-Marc; Kulcsár, Caroline; Raynaud, Henri-François; Fusco, Thierry

2004-12-01

Classical Adaptive Optics suffer from a limitation of the corrected Field Of View. This drawback has lead to the development of MultiConjugated Adaptive Optics. While the first MCAO experimental set-ups are presently under construction, little attention has been paid to the control loop. This is however a key element in the optimization process especially for MCAO systems. Different approaches have been proposed in recent articles for astronomical applications : simple integrator, Optimized Modal Gain Integrator and Kalman filtering. We study here Kalman filtering which seems a very promising solution. Following the work of Brice Leroux, we focus on a frequential characterization of kalman filters, computing a transfer matrix. The result brings much information about their behaviour and allows comparisons with classical controllers. It also appears that straightforward improvements of the system models can lead to static aberrations and vibrations filtering. Simulation results are proposed and analysed thanks to our frequential characterization. Related problems such as model errors, aliasing effect reduction or experimental implementation and testing of Kalman filter control loop on a simplified MCAO experimental set-up could be then discussed.

DACS II - A distributed thermal/mechanical loads data acquisition and control system

NASA Technical Reports Server (NTRS)

Zamanzadeh, Behzad; Trover, William F.; Anderson, Karl F.

1987-01-01

A distributed data acquisition and control system has been developed for the NASA Flight Loads Research Facility. The DACS II system is composed of seven computer systems and four array processors configured as a main computer system, three satellite computer systems, and 13 analog input/output systems interconnected through three independent data networks. Up to three independent heating and loading tests can be run concurrently on different test articles or the entire system can be used on a single large test such as a full scale hypersonic aircraft. Thermal tests can include up to 512 independent adaptive closed loop control channels. The control system can apply up to 20 MW of heating to a test specimen while simultaneously applying independent mechanical loads. Each thermal control loop is capable of heating a structure at rates of up to 150 F per second over a temperature range of -300 to +2500 F. Up to 64 independent mechanical load profiles can be commanded along with thermal control. Up to 1280 analog inputs monitor temperature, load, displacement and strain on the test specimens with real time data displayed on up to 15 terminals as color plots and tabular data displays. System setup and operation is accomplished with interactive menu-driver displays with extensive facilities to assist the users in all phases of system operation.

Human Haptic Interaction with Soft Objects: Discriminability, Force Control, and Contact Visualization

DTIC Science & Technology

1998-01-01

consisted of a videomicroscopy system and a tactile stimulator system. By using this setup, real-time images from the contact region as wvell as the... Videomicroscopy system . 4.3.2 Tactile stimulator svsteln . 4.3.3 Real-time imaging setup. 4.3.4 Active and passive touch experiments. 4.3.5...contact process is an important step. In this study, therefore, a videomicroscopy system was built’to visualize the contact re- gion of the fingerpad

A Demonstration Setup to Simulate Detection of Planets outside the Solar System

ERIC Educational Resources Information Center

Choopan, W.; Ketpichainarong, W.; Laosinchai, P.; Panijpan, B.

2011-01-01

We constructed a simple demonstration setup to simulate an extrasolar planet and its star revolving around the system's centre of mass. Periodic dimming of light from the star by the transiting planet and the star's orbital revolution simulate the two major ways of deducing the presence of an exoplanet near a distant star. Apart from being a…

Investigating a compact phantom and setup for testing body sound transducers

PubMed Central

Mansy, Hansen A; Grahe, Joshua; Royston, Thomas J; Sandler, Richard H

2011-01-01

Contact transducers are a key element in experiments involving body sounds. The characteristics of these devices are often not known with accuracy. There are no standardized calibration setups or procedures for testing these sensors. This study investigated the characteristics of a new computer-controlled sound source phantom for testing sensors. Results suggested that sensors with different sizes require special phantom requirements. The effectiveness of certain approaches on increasing the spatial and spectral uniformity of the phantom surface signal was studied. Non-uniformities >20 dB were removable, which can be particularly helpful in comparing the characteristics of different size sensors more accurately. PMID:21496795

Optimized linear motor and digital PID controller setup used in Mössbauer spectrometer

NASA Astrophysics Data System (ADS)

Kohout, Pavel; Kouřil, Lukáš; Navařík, Jakub; Novák, Petr; Pechoušek, Jiří

2014-10-01

Optimization of a linear motor and digital PID controller setup used in a Mössbauer spectrometer is presented. Velocity driving system with a digital PID feedback subsystem was developed in the LabVIEW graphical environment and deployed on the sbRIO real-time hardware device (National Instruments). The most important data acquisition processes are performed as real-time deterministic tasks on an FPGA chip. Velocity transducer of a double loudspeaker type with a power amplifier circuit is driven by the system. Series of calibration measurements were proceeded to find the optimal setup of the P, I, D parameters together with velocity error signal analysis. The shape and given signal characteristics of the velocity error signal are analyzed in details. Remote applications for controlling and monitoring the PID system from computer or smart phone, respectively, were also developed. The best setup and P, I, D parameters were set and calibration spectrum of α-Fe sample with an average nonlinearity of the velocity scale below 0.08% was collected. Furthermore, the width of the spectral line below 0.30 mm/s was observed. Powerful and complex velocity driving system was designed.

Photon-phonon-photon transfer in optomechanics

PubMed Central

Rakhubovsky, Andrey A.; Filip, Radim

2017-01-01

We consider transfer of a highly nonclassical quantum state through an optomechanical system. That is we investigate a protocol consisting of sequential upload, storage and reading out of the quantum state from a mechanical mode of an optomechanical system. We show that provided the input state is in a test-bed single-photon Fock state, the Wigner function of the recovered state can have negative values at the origin, which is a manifest of nonclassicality of the quantum state of the macroscopic mechanical mode and the overall transfer protocol itself. Moreover, we prove that the recovered state is quantum non-Gaussian for wide range of setup parameters. We verify that current electromechanical and optomechanical experiments can test this complete transfer of single photon. PMID:28436461

Deep Charging Evaluation of Satellite Power and Communication System Components

NASA Technical Reports Server (NTRS)

Schneider, T. A.; Vaughn, J. A.; Chu, B.; Wong, F.; Gardiner, G.; Wright, K. H.; Phillips, B.

2016-01-01

A set of deep charging tests has been carried out by NASA's Marshall Space Flight Center on subscale flight-like samples developed by Space Systems/Loral, LLC. The samples, which included solar array wire coupons, a photovoltaic cell coupon, and a coaxial microwave transmission cable, were placed in passive and active (powered) circuit configurations and exposed to electron radiation. The energy of the electron radiation was chosen to deeply penetrate insulating (dielectric) materials on each sample. Each circuit configuration was monitored to determine if potentially damaging electrostatic discharge events (arcs) were developed on the coupon as a result of deep charging. The motivation for the test, along with charging levels, experimental setup, sample details, and results will be discussed.

Multipacting simulation and test results of BNL 704 MHz SRF gun

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu W.; Belomestnykh, S.; Ben-Zvi, I.

The BNL 704MHz SRF gun has a grooved choke joint to support the photo-cathode. Due to the distortion of grooves at the choke joint during the BCP for the choke joint, several multipacting barriers showed up when it was tested with Nb cathode stalk at JLab. We built a setup to use the spare large grain SRF cavity to test and condition the multipacting at BNL with various power sources up to 50kW. The test is carried out in three stages: testing the cavity performance without cathode, testing the cavity with the Nb cathode stalk that was used at Jlab,more » and testing the cavity with a copper cathode stalk that is based on the design for the SRF gun. This paper summarizes the results of multipacting simulation, and presents the large grain cavity test setup and the test results.« less

Delivery of calibration workshops covering herbicide application equipment : final report.

DOT National Transportation Integrated Search

2014-03-31

Proper herbicide sprayer set-up and calibration are critical to the success of the Oklahoma Department of Transportation (ODOT) herbicide program. Sprayer system set-up and calibration training is provided in annual continuing education herbicide wor...

Laser-induced fluorescence detection platform for point-of-care testing

NASA Astrophysics Data System (ADS)

Berner, Marcel; Hilbig, Urs; Schubert, Markus B.; Gauglitz, Günter

2017-08-01

Point-of-care testing (POCT) devices for continuous low-cost monitoring of critical patient parameters require miniaturized and integrated setups for performing quick high-sensitivity analyses, away from central clinical laboratories. This work presents a novel and promising laser-induced fluorescence platform for measurements in direct optical test formats that leads towards such powerful POCT devices based on fluorescence-labeled immunoassays. Ultimate sensitivity of thin film photodetectors, integrated with microfluidics, and a comprehensive optimization of all system components aim at low-level signal detection in the targeted biosensor application. The setup acquires fluorescence signals from the volume of a microfluidic channel. An innovative sandwiching process forms a flow channel in the microfluidic chips by embedding laser-cut double-sided adhesive tapes. The custom fit of amorphous silicon based photodiode arrays to the geometry of the flow channel enables miniaturization, fully adequate for POCT devices. A free-beam laser excitation with line focus provides excellent alignment stability, allows for easy and reliable swapping of the disposable microfluidic chips, and therewith greatly improves the ease of use of the resulting integrated device. As a proof-of-concept of this novel in-volume measurement approach, the limit of detection for the dye DY636-COOH in pure water as a model fluorophore is examined and found to be 26 nmol l-1 .

Reflective Occultation Mask for Evaluation of Occulter Designs for Planet Finding

NASA Technical Reports Server (NTRS)

Hagopian, John; Lyon, Richard; Shiri, Shahram; Roman, Patrick

2011-01-01

Advanced formation flying occulter designs utilize a large occulter mask flying in formation with an imaging telescope to block and null starlight to allow imaging of faint planets in exosolar systems. A paper describes the utilization of subscale reflective occultation masks to evaluate formation flying occulter designs. The use of a reflective mask allows mounting of the occulter by conventional means and simplifies the test configuration. The innovation alters the test set-up to allow mounting of the mask using standard techniques to eliminate the problems associated with a standard configuration. The modified configuration uses a reflective set-up whereby the star simulator reflects off of a reflective occulting mask and into an evaluation telescope. Since the mask is sized to capture all rays required for the imaging test, it can be mounted directly to a supporting fixture without interfering with the beam. Functionally, the reflective occultation mask reflects light from the star simulator instead of transmitting it, with a highly absorptive carbon nanotube layer simulating the occulter blocking mask. A subscale telescope images the star source and companion dim source that represents a planet. The primary advantage of this is that the occulter can be mounted conventionally instead of using diffractive wires or magnetic levitation.

So ware-Defined Network Solutions for Science Scenarios: Performance Testing Framework and Measurements

DOE Office of Scientific and Technical Information (OSTI.GOV)

Settlemyer, Bradley; Kettimuthu, R.; Boley, Josh

High-performance scientific work flows utilize supercomputers, scientific instruments, and large storage systems. Their executions require fast setup of a small number of dedicated network connections across the geographically distributed facility sites. We present Software-Defined Network (SDN) solutions consisting of site daemons that use dpctl, Floodlight, ONOS, or OpenDaylight controllers to set up these connections. The development of these SDN solutions could be quite disruptive to the infrastructure, while requiring a close coordination among multiple sites; in addition, the large number of possible controller and device combinations to investigate could make the infrastructure unavailable to regular users for extended periods ofmore » time. In response, we develop a Virtual Science Network Environment (VSNE) using virtual machines, Mininet, and custom scripts that support the development, testing, and evaluation of SDN solutions, without the constraints and expenses of multi-site physical infrastructures; furthermore, the chosen solutions can be directly transferred to production deployments. By complementing VSNE with a physical testbed, we conduct targeted performance tests of various SDN solutions to help choose the best candidates. In addition, we propose a switching response method to assess the setup times and throughput performances of different SDN solutions, and present experimental results that show their advantages and limitations.« less

Automation and results of Adjacent Band Emission testing

DOT National Transportation Integrated Search

2015-03-01

Problem Statement : Multiple groups conduct tests in various ways - Outcomes vary based on test setup and assumptions - No standard has been established to conduct such tests - Spectrum is scarce and the need for compliance testing will only increase...

TAMOAS: In Situ Gasometry in the Atmosphere with Solid Electrolyte Sensors on BEXUS-19

NASA Astrophysics Data System (ADS)

Bronowski, A.; Clemens, R.; Jaster, T.; Kosel, F.; Matyash, I.; Westphal, A.

2015-09-01

A student experiment developed for testing gas sensors in the stratosphere is described. The setup consists of a measurement electronic running miniaturized in situ amperiometric gas sensors based on different solid state electrolytes dedicated for oxygen, ozone and atomic oxygen. The experiment took place at Esrange Space Center in October 2014. The setup was attached to the high-altitude balloon BEXUS-19 and reached an altitude of 27 km at night. The primary objective was to test the prototype sensors and to gain data during flight.

Length matters: Improved high field EEG-fMRI recordings using shorter EEG cables.

PubMed

Assecondi, Sara; Lavallee, Christina; Ferrari, Paolo; Jovicich, Jorge

2016-08-30

The use of concurrent EEG-fMRI recordings has increased in recent years, allowing new avenues of medical and cognitive neuroscience research; however, currently used setups present problems with data quality and reproducibility. We propose a compact experimental setup for concurrent EEG-fMRI at 4T and compare it to a more standard reference setup. The compact setup uses short EEG cables connecting to the amplifiers, which are placed right at the back of the head RF coil on a form-fitting extension force-locked to the patient MR bed. We compare the two setups in terms of sensitivity to MR-room environmental noise, interferences between measuring devices (EEG or fMRI), and sensitivity to functional responses in a visual stimulation paradigm. The compact setup reduces the system sensitivity to both external noise and MR-induced artefacts by at least 60%, with negligible EEG noise induced from the mechanical vibrations of the cryogenic cooling compression pump. The compact setup improved EEG data quality and the overall performance of MR-artifact correction techniques. Both setups were similar in terms of the fMRI data, with higher reproducibility for cable placement within the scanner in the compact setup. This improved compact setup may be relevant to MR laboratories interested in reducing the sensitivity of their EEG-fMRI experimental setup to external noise sources, setting up an EEG-fMRI workplace for the first time, or for creating a more reproducible configuration of equipment and cables. Implications for safety and ergonomics are discussed. Copyright © 2016 Elsevier B.V. All rights reserved.

A Method for Assessing the Accuracy of a Photogrammetry System for Precision Deployable Structures

NASA Technical Reports Server (NTRS)

Moore, Ashley

2005-01-01

The measurement techniques used to validate analytical models of large deployable structures are an integral Part of the technology development process and must be precise and accurate. Photogrammetry and videogrammetry are viable, accurate, and unobtrusive methods for measuring such large Structures. Photogrammetry uses Software to determine the three-dimensional position of a target using camera images. Videogrammetry is based on the same principle, except a series of timed images are analyzed. This work addresses the accuracy of a digital photogrammetry system used for measurement of large, deployable space structures at JPL. First, photogrammetry tests are performed on a precision space truss test article, and the images are processed using Photomodeler software. The accuracy of the Photomodeler results is determined through, comparison with measurements of the test article taken by an external testing group using the VSTARS photogrammetry system. These two measurements are then compared with Australis photogrammetry software that simulates a measurement test to predict its accuracy. The software is then used to study how particular factors, such as camera resolution and placement, affect the system accuracy to help design the setup for the videogrammetry system that will offer the highest level of accuracy for measurement of deploying structures.

MEMS deformable mirror for wavefront correction of large telescopes

NASA Astrophysics Data System (ADS)

Manhart, Sigmund; Vdovin, Gleb; Collings, Neil; Sodnik, Zoran; Nikolov, Susanne; Hupfer, Werner

2017-11-01

A 50 mm diameter membrane mirror was designed and manufactured at TU Delft. It is made from bulk silicon by micromachining - a technology primarily used for micro-electromechanical systems (MEMS). The mirror unit is equipped with 39 actuator electrodes and can be electrostatically deformed to correct wavefront errors in optical imaging systems. Performance tests on the deformable mirror were carried out at Astrium GmbH using a breadboard setup with a wavefront sensor and a closed-loop control system. It was found that the deformable membrane mirror is well suited for correction of low order wavefront errors as they must be expected in lightweighted space telescopes.

Accuracy of human motion capture systems for sport applications; state-of-the-art review.

PubMed

van der Kruk, Eline; Reijne, Marco M

2018-05-09

Sport research often requires human motion capture of an athlete. It can, however, be labour-intensive and difficult to select the right system, while manufacturers report on specifications which are determined in set-ups that largely differ from sport research in terms of volume, environment and motion. The aim of this review is to assist researchers in the selection of a suitable motion capture system for their experimental set-up for sport applications. An open online platform is initiated, to support (sport)researchers in the selection of a system and to enable them to contribute and update the overview. systematic review; Method: Electronic searches in Scopus, Web of Science and Google Scholar were performed, and the reference lists of the screened articles were scrutinised to determine human motion capture systems used in academically published studies on sport analysis. An overview of 17 human motion capture systems is provided, reporting the general specifications given by the manufacturer (weight and size of the sensors, maximum capture volume, environmental feasibilities), and calibration specifications as determined in peer-reviewed studies. The accuracy of each system is plotted against the measurement range. The overview and chart can assist researchers in the selection of a suitable measurement system. To increase the robustness of the database and to keep up with technological developments, we encourage researchers to perform an accuracy test prior to their experiment and to add to the chart and the system overview (online, open access).

A catheter friction tester using balance sensor: Combined evaluation of the effects of mechanical properties of tubing materials and surface coatings.

PubMed

Røn, Troels; Jacobsen, Kristina Pilgaard; Lee, Seunghwan

2018-04-24

In this study, we introduce a new experimental approach to characterize the forces emerging from simulated catherization. This setup allows for a linear translation of urinary catheters in vertical direction as controlled by an actuator. By employing silicone-based elastomer with a duct of comparable diameter with catheters as urethra model, sliding contacts during the translation of catheters along the duct is generated. A most unique design and operation feature of this setup is that a digital balance was employed as the sensor to detect emerging forces from simulated catherization. Moreover, the possibility to give a variation in environment (ambient air vs. water), clearance, elasticity, and curvature of silicone-based urethra model allows for the detection of forces arising from diverse simulated catherization conditions. Two types of commercially available catheters varying in tubing materials and surface coatings were tested together with their respective uncoated catheter tubing. The first set of testing on the catheter samples showed that this setup can probe the combined effect from flexural strain of bulk tubing materials and slipperiness of surface coatings, both of which are expected to affect the comfort and smooth gliding in clinical catherization. We argue that this new experimental setup can provide unique and valuable information in preclinical friction testing of urinary catheters. Copyright © 2018 Elsevier Ltd. All rights reserved.

Dynamic MTF, an innovative test bench for detector characterization

NASA Astrophysics Data System (ADS)

Emmanuel, Rossi; Raphaël, Lardière; Delmonte, Stephane

2017-11-01

PLEIADES HR are High Resolution satellites for Earth observation. Placed at 695km they reach a 0.7m spatial resolution. To allow such performances, the detectors are working in a TDI mode (Time and Delay Integration) which consists in a continuous charge transfer from one line to the consecutive one while the image is passing on the detector. The spatial resolution, one of the most important parameter to test, is characterized by the MTF (Modulation Transfer Function). Usually, detectors are tested in a staring mode. For a higher level of performances assessment, a dedicated bench has been set-up, allowing detectors' MTF characterization in the TDI mode. Accuracy and reproducibility are impressive, opening the door to new perspectives in term of HR imaging systems testing.

Application of High Speed Digital Image Correlation in Rocket Engine Hot Fire Testing

NASA Technical Reports Server (NTRS)

Gradl, Paul R.; Schmidt, Tim

2016-01-01

Hot fire testing of rocket engine components and rocket engine systems is a critical aspect of the development process to understand performance, reliability and system interactions. Ground testing provides the opportunity for highly instrumented development testing to validate analytical model predictions and determine necessary design changes and process improvements. To properly obtain discrete measurements for model validation, instrumentation must survive in the highly dynamic and extreme temperature application of hot fire testing. Digital Image Correlation has been investigated and being evaluated as a technique to augment traditional instrumentation during component and engine testing providing further data for additional performance improvements and cost savings. The feasibility of digital image correlation techniques were demonstrated in subscale and full scale hotfire testing. This incorporated a pair of high speed cameras to measure three-dimensional, real-time displacements and strains installed and operated under the extreme environments present on the test stand. The development process, setup and calibrations, data collection, hotfire test data collection and post-test analysis and results are presented in this paper.

HECTOR: A 240kV micro-CT setup optimized for research

NASA Astrophysics Data System (ADS)

Masschaele, Bert; Dierick, Manuel; Van Loo, Denis; Boone, Matthieu N.; Brabant, Loes; Pauwels, Elin; Cnudde, Veerle; Van Hoorebeke, Luc

2013-10-01

X-ray micro-CT has become a very powerful and common tool for non-destructive three-dimensional (3D) visualization and analysis of objects. Many systems are commercially available, but they are typically limited in terms of operational freedom both from a mechanical point of view as well as for acquisition routines. HECTOR is the latest system developed by the Ghent University Centre for X-ray Tomography (http://www.ugct.ugent.be) in collaboration with X-Ray Engineering (XRE bvba, Ghent, Belgium). It consists of a mechanical setup with nine motorized axes and a modular acquisition software package and combines a microfocus directional target X-ray source up to 240 kV with a large flat-panel detector. Provisions are made to install a line-detector for a maximal operational range. The system can accommodate samples up to 80 kg, 1 m long and 80 cm in diameter while it is also suited for high resolution (down to 4 μm) tomography. The bi-directional detector tiling is suited for large samples while the variable source-detector distance optimizes the signal to noise ratio (SNR) for every type of sample, even with peripheral equipment such as compression stages or climate chambers. The large vertical travel of 1 m can be used for helical scanning and a vertical detector rotation axis allows laminography experiments. The setup is installed in a large concrete bunker to allow accommodation of peripheral equipment such as pumps, chillers, etc., which can be integrated in the modular acquisition software to obtain a maximal correlation between the environmental control and the CT data taken. The acquisition software does not only allow good coupling with the peripheral equipment but its scripting feature is also particularly interesting for testing new and exotic acquisition routines.

Oceanic Whitecaps and Associated, Bubble-Mediated, Air-Sea Exchange Processes

DTIC Science & Technology

1992-10-01

experiments performed in laboratory conditions using Air-Sea Exchange Monitoring System (A-SEMS). EXPERIMENTAL SET-UP In a first look, the Air-Sea Exchange...Model 225, equipped with a Model 519 plug-in module. Other complementary information on A-SEMS along with results from first tests and calibration...between 9.50C and 22.40C within the first 24 hours after transferring the water sample into laboratory conditions. The results show an enhancement of

Implementing a Multiplexed System of Detectors for Higher Photon Counting Rates

DTIC Science & Technology

2007-01-01

D1 D2 Fig. 3. (a) Setup for testing different arrangements of InGaAs SPAD assemblies; (b) three different InGaAs SPAD assemblies; ( c ) schematic of...presently available, either commercial or prototype, the deadtimes range from ≈50 ns for actively quenched single photon avalanche detectors ( SPADs ...to ≈10 µs for passively quenched SPADs , although even actively quenched SPADs sometimes employ µs deadtimes to avoid excessive afterpulsing rates. In

Development of a Laboratory-scale Test Facility to Investigate Armor Solutions against Buried Explosive Threats

DTIC Science & Technology

2009-12-01

Centro de Estudios Superiores Navales Mexican Navy México, DF México 5. Dr. Jose O. Sinibaldi Naval Postgraduate School Monterey, CA. 6. Dr. Robert S. Hixson Naval Postgraduate School Monterey, CA ...EXPERIMENTAL SETUP AND PROCEDURE............................................. 67 A. HIGH-SPEED VISION SYSTEM...Mexican Navy, “Con la Satisfacción del Deber Cumplido.” To all of them, I am sincerely grateful. xviii THIS PAGE INTENTIONALLY LEFT BLANK xix

Long Endurance Underwater Power System

DTIC Science & Technology

1989-09-01

Figures 7.3 through 7.8. Data analysis was done using the Excel spreadsheet program on an IBM compatible computer -w.d utsported to a MALcintosh for...shall be compared with data obtained from non-leaking gill carridges for a mor complete analysis . 4) The pump attached to the test setup was not...BACKGROUND 5 V. ANALYSIS 6 VI. RESULTS AND CONCLUSIONS 6 )Preferred Method 7 VI. REFERENCES 11 App- nd.x-.1 12 SECTION - II ALWATT HY.HG•N GENERATOR I

An optimal policy for a single-vendor and a single-buyer integrated system with setup cost reduction and process-quality improvement

NASA Astrophysics Data System (ADS)

Shu, Hui; Zhou, Xideng

2014-05-01

The single-vendor single-buyer integrated production inventory system has been an object of study for a long time, but little is known about the effect of investing in reducing setup cost reduction and process-quality improvement for an integrated inventory system in which the products are sold with free minimal repair warranty. The purpose of this article is to minimise the integrated cost by optimising simultaneously the number of shipments and the shipment quantity, the setup cost, and the process quality. An efficient algorithm procedure is proposed for determining the optimal decision variables. A numerical example is presented to illustrate the results of the proposed models graphically. Sensitivity analysis of the model with respect to key parameters of the system is carried out. The paper shows that the proposed integrated model can result in significant savings in the integrated cost.

Hybrid Pareto artificial bee colony algorithm for multi-objective single machine group scheduling problem with sequence-dependent setup times and learning effects.

PubMed

Yue, Lei; Guan, Zailin; Saif, Ullah; Zhang, Fei; Wang, Hao

2016-01-01

Group scheduling is significant for efficient and cost effective production system. However, there exist setup times between the groups, which require to decrease it by sequencing groups in an efficient way. Current research is focused on a sequence dependent group scheduling problem with an aim to minimize the makespan in addition to minimize the total weighted tardiness simultaneously. In most of the production scheduling problems, the processing time of jobs is assumed as fixed. However, the actual processing time of jobs may be reduced due to "learning effect". The integration of sequence dependent group scheduling problem with learning effects has been rarely considered in literature. Therefore, current research considers a single machine group scheduling problem with sequence dependent setup times and learning effects simultaneously. A novel hybrid Pareto artificial bee colony algorithm (HPABC) with some steps of genetic algorithm is proposed for current problem to get Pareto solutions. Furthermore, five different sizes of test problems (small, small medium, medium, large medium, large) are tested using proposed HPABC. Taguchi method is used to tune the effective parameters of the proposed HPABC for each problem category. The performance of HPABC is compared with three famous multi objective optimization algorithms, improved strength Pareto evolutionary algorithm (SPEA2), non-dominated sorting genetic algorithm II (NSGAII) and particle swarm optimization algorithm (PSO). Results indicate that HPABC outperforms SPEA2, NSGAII and PSO and gives better Pareto optimal solutions in terms of diversity and quality for almost all the instances of the different sizes of problems.

Study of UV imaging technology for noninvasive detection of latent fingerprints

NASA Astrophysics Data System (ADS)

Li, Hong-xia; Cao, Jing; Niu, Jie-qing; Huang, Yun-gang

2013-09-01

Using UV imaging technology, according to the special absorption 、reflection 、scattering and fluorescence characterization of the various residues in fingerprints (fatty acid ester, protein, and carboxylic acid salts etc) to the UV light, weaken or eliminate the background disturbance to increase the brightness contrast of fingerprints with the background, and design、setup the illumination optical system and UV imaging system, the noninvasive detection of latent fingerprints remaining on various object surface are studied. In the illumination optical system, using the 266nm UV Nd:YAG solid state laser as illumination light source, by calculating the best coupling conditions of the laser beam with UV liquid core fiber and analyzing the beam transforming characterizations, we designed and setup the optical system to realize the UV imaging uniform illumination. In the UV imaging system, the UV lens is selected as the fingerprint imaging element, and the UV intensified CCD (ICCD) which consists of a second-generation UV image intensifier and a CCD coupled by fiber plate and taper directly are used as the imaging sensing element. The best imaging conditions of the UV lens with ICCD were analyzed and the imaging system was designed and setup. In this study, by analyzing the factors which influence the detection effect, optimal design and setup the illumination system and imaging system, latent fingerprints on the surface of the paint tin box、plastic、smooth paper、notebook paper and print paper were noninvasive detected and appeared, and the result meet the fingerprint identification requirements in forensic science.

An experimental study of potential residential and commercial applications of small-scale hybrid power systems

NASA Astrophysics Data System (ADS)

Acosta, Michael Anthony

The research presented in this thesis provides an understanding of small-scale hybrid power systems. Experiments were conducted to identify potential applications of renewable energy in residential and commercial applications in the Rio Grande Valley of Texas. Solar and wind energy converted into electric energy was stored in batteries and inverted to power common household and commercial appliances. Several small to medium size hybrid power systems were setup and utilized to conduct numerous tests to study renewable energy prospects and feasibility for various applications. The experimental results obtained indicate that carefully constructed solar power systems can provide people living in isolated communities with sufficient energy to consistently meet their basic power needs.

Virtual Exercise Training Software System

NASA Technical Reports Server (NTRS)

Vu, L.; Kim, H.; Benson, E.; Amonette, W. E.; Barrera, J.; Perera, J.; Rajulu, S.; Hanson, A.

2018-01-01

The purpose of this study was to develop and evaluate a virtual exercise training software system (VETSS) capable of providing real-time instruction and exercise feedback during exploration missions. A resistive exercise instructional system was developed using a Microsoft Kinect depth-camera device, which provides markerless 3-D whole-body motion capture at a small form factor and minimal setup effort. It was hypothesized that subjects using the newly developed instructional software tool would perform the deadlift exercise with more optimal kinematics and consistent technique than those without the instructional software. Following a comprehensive evaluation in the laboratory, the system was deployed for testing and refinement in the NASA Extreme Environment Mission Operations (NEEMO) analog.

Machining and brazing of accelerating RF cavity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ghodke, S.R.; Barnwal, Rajesh; Mondal, Jayant, E-mail: ghodke_barc@yahoo.co.in

2014-07-01

BARC has developed 2856 MHz accelerating cavities for 6 MeV, 9 MeV and 10 MeV RF Linac. New vendors are developed for mass production of accelerating cavity for future projects. New vendors are developing for diamond turning machining, cleaning and brazing processes. Fabrication involved material testing, CNC diamond turning of cavity, cavity cleaning and brazing. Before and after brazing resonance frequency (RF) of cavity was checked with vector network analyser (VNA). A power feed test setup is also fabricated to test power feed cavity before brazing. This test setup will be used to find out assembly performance of power feedmore » cavity and its coupler. This paper discusses about nano machining, cleaning and brazing processes of RF cavities. (author)« less

Automated PCR setup for forensic casework samples using the Normalization Wizard and PCR Setup robotic methods.

PubMed

Greenspoon, S A; Sykes, K L V; Ban, J D; Pollard, A; Baisden, M; Farr, M; Graham, N; Collins, B L; Green, M M; Christenson, C C

2006-12-20

Human genome, pharmaceutical and research laboratories have long enjoyed the application of robotics to performing repetitive laboratory tasks. However, the utilization of robotics in forensic laboratories for processing casework samples is relatively new and poses particular challenges. Since the quantity and quality (a mixture versus a single source sample, the level of degradation, the presence of PCR inhibitors) of the DNA contained within a casework sample is unknown, particular attention must be paid to procedural susceptibility to contamination, as well as DNA yield, especially as it pertains to samples with little biological material. The Virginia Department of Forensic Science (VDFS) has successfully automated forensic casework DNA extraction utilizing the DNA IQ(trade mark) System in conjunction with the Biomek 2000 Automation Workstation. Human DNA quantitation is also performed in a near complete automated fashion utilizing the AluQuant Human DNA Quantitation System and the Biomek 2000 Automation Workstation. Recently, the PCR setup for casework samples has been automated, employing the Biomek 2000 Automation Workstation and Normalization Wizard, Genetic Identity version, which utilizes the quantitation data, imported into the software, to create a customized automated method for DNA dilution, unique to that plate of DNA samples. The PCR Setup software method, used in conjunction with the Normalization Wizard method and written for the Biomek 2000, functions to mix the diluted DNA samples, transfer the PCR master mix, and transfer the diluted DNA samples to PCR amplification tubes. Once the process is complete, the DNA extracts, still on the deck of the robot in PCR amplification strip tubes, are transferred to pre-labeled 1.5 mL tubes for long-term storage using an automated method. The automation of these steps in the process of forensic DNA casework analysis has been accomplished by performing extensive optimization, validation and testing of the software methods.

Neutron Radiography of Fluid Flow for Geothermal Energy Research

NASA Astrophysics Data System (ADS)

Bingham, P.; Polsky, Y.; Anovitz, L.; Carmichael, J.; Bilheux, H.; Jacobsen, D.; Hussey, D.

Enhanced geothermal systems seek to expand the potential for geothermal energy by engineering heat exchange systems within the earth. A neutron radiography imaging method has been developed for the study of fluid flow through rock under environmental conditions found in enhanced geothermal energy systems. For this method, a pressure vessel suitable for neutron radiography was designed and fabricated, modifications to imaging instrument setups were tested, multiple contrast agents were tested, and algorithms developed for tracking of flow. The method has shown success for tracking of single phase flow through a manufactured crack in a 3.81 cm (1.5 inch) diameter core within a pressure vessel capable of confinement up to 69 MPa (10,000 psi) using a particle tracking approach with bubbles of fluorocarbon-based fluid as the ;particles; and imaging with 10 ms exposures.

Flying Boresight for Advanced Testing and Calibration of Tracking Antennas and Flight Path Simulations

NASA Astrophysics Data System (ADS)

Hafner, D.

2015-09-01

The application of ground-based boresight sources for calibration and testing of tracking antennas usually entails various difficulties, mostly due to unwanted ground effects. To avoid this problem, DLR MORABA developed a small, lightweight, frequency-adjustable S-band boresight source, mounted on a small remote-controlled multirotor aircraft. Highly accurate GPS-supported, position and altitude control functions allow both, very steady positioning of the aircraft in mid-air, and precise waypoint-based, semi-autonomous flights. In contrast to fixed near-ground boresight sources this flying setup enables to avoid obstructions in the Fresnel zone between source and antenna. Further, it minimizes ground reflections and other multipath effects which can affect antenna calibration. In addition, the large operating range of a flying boresight simplifies measurements in the far field of the antenna and permits undisturbed antenna pattern tests. A unique application is the realistic simulation of sophisticated flight paths, including overhead tracking and demanding trajectories of fast objects such as sounding rockets. Likewise, dynamic tracking tests are feasible which provide crucial information about the antenna pedestal performance — particularly at high elevations — and reveal weaknesses in the autotrack control loop of tracking antenna systems. During acceptance tests of MORABA's new tracking antennas, a manned aircraft was never used, since the Flying Boresight surpassed all expectations regarding usability, efficiency, and precision. Hence, it became an integral part of MORABA's standard antenna setup and calibration procedures.

Precision assessment of model-based RSA for a total knee prosthesis in a biplanar set-up.

PubMed

Trozzi, C; Kaptein, B L; Garling, E H; Shelyakova, T; Russo, A; Bragonzoni, L; Martelli, S

2008-10-01

Model-based Roentgen Stereophotogrammetric Analysis (RSA) was recently developed for the measurement of prosthesis micromotion. Its main advantage is that markers do not need to be attached to the implants as traditional marker-based RSA requires. Model-based RSA has only been tested in uniplanar radiographic set-ups. A biplanar set-up would theoretically facilitate the pose estimation algorithm, since radiographic projections would show more different shape features of the implants than in uniplanar images. We tested the precision of model-based RSA and compared it with that of the traditional marker-based method in a biplanar set-up. Micromotions of both tibial and femoral components were measured with both the techniques from double examinations of patients participating in a clinical study. The results showed that in the biplanar set-up model-based RSA presents a homogeneous distribution of precision for all the translation directions, but an inhomogeneous error for rotations, especially internal-external rotation presented higher errors than rotations about the transverse and sagittal axes. Model-based RSA was less precise than the marker-based method, although the differences were not significant for the translations and rotations of the tibial component, with the exception of the internal-external rotations. For both prosthesis components the precisions of model-based RSA were below 0.2 mm for all the translations, and below 0.3 degrees for rotations about transverse and sagittal axes. These values are still acceptable for clinical studies aimed at evaluating total knee prosthesis micromotion. In a biplanar set-up model-based RSA is a valid alternative to traditional marker-based RSA where marking of the prosthesis is an enormous disadvantage.

Radiated Emissions Test Approach

DOT National Transportation Integrated Search

2015-10-02

1. Draft Department of Transportation (DOT) Test Plan to Develop : Interference Tolerance Masks for GNSS Receivers in the L1 : Radiofrequency Band (1559 1610 MHz) provides high level : overview of radiated emissions test setup : 2. Presenta...

SU-F-P-18: Development of the Technical Training System for Patient Set-Up Considering Rotational Correction in the Virtual Environment Using Three-Dimensional Computer Graphic Engine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Imura, K; Fujibuchi, T; Hirata, H

Purpose: Patient set-up skills in radiotherapy treatment room have a great influence on treatment effect for image guided radiotherapy. In this study, we have developed the training system for improving practical set-up skills considering rotational correction in the virtual environment away from the pressure of actual treatment room by using three-dimensional computer graphic (3DCG) engine. Methods: The treatment room for external beam radiotherapy was reproduced in the virtual environment by using 3DCG engine (Unity). The viewpoints to perform patient set-up in the virtual treatment room were arranged in both sides of the virtual operable treatment couch to assume actual performancemore » by two clinical staffs. The position errors to mechanical isocenter considering alignment between skin marker and laser on the virtual patient model were displayed by utilizing numerical values expressed in SI units and the directions of arrow marks. The rotational errors calculated with a point on the virtual body axis as the center of each rotation axis for the virtual environment were corrected by adjusting rotational position of the body phantom wound the belt with gyroscope preparing on table in a real space. These rotational errors were evaluated by describing vector outer product operations and trigonometric functions in the script for patient set-up technique. Results: The viewpoints in the virtual environment allowed individual user to visually recognize the position discrepancy to mechanical isocenter until eliminating the positional errors of several millimeters. The rotational errors between the two points calculated with the center point could be efficiently corrected to display the minimum technique mathematically by utilizing the script. Conclusion: By utilizing the script to correct the rotational errors as well as accurate positional recognition for patient set-up technique, the training system developed for improving patient set-up skills enabled individual user to indicate efficient positional correction methods easily.« less

Analysis of image sharpness reproducibility on a novel engineered micro-CT scanner with variable geometry and embedded recalibration software.

PubMed

Panetta, D; Belcari, N; Del Guerra, A; Bartolomei, A; Salvadori, P A

2012-04-01

This study investigates the reproducibility of the reconstructed image sharpness, after modifications of the geometry setup, for a variable magnification micro-CT (μCT) scanner. All the measurements were performed on a novel engineered μCT scanner for in vivo imaging of small animals (Xalt), which has been recently built at the Institute of Clinical Physiology of the National Research Council (IFC-CNR, Pisa, Italy), in partnership with the University of Pisa. The Xalt scanner is equipped with an integrated software for on-line geometric recalibration, which will be used throughout the experiments. In order to evaluate the losses of image quality due to modifications of the geometry setup, we have made 22 consecutive acquisitions by changing alternatively the system geometry between two different setups (Large FoV - LF, and High Resolution - HR). For each acquisition, the tomographic images have been reconstructed before and after the on-line geometric recalibration. For each reconstruction, the image sharpness was evaluated using two different figures of merit: (i) the percentage contrast on a small bar pattern of fixed frequency (f = 5.5 lp/mm for the LF setup and f = 10 lp/mm for the HR setup) and (ii) the image entropy. We have found that, due to the small-scale mechanical uncertainty (in the order of the voxel size), a recalibration is necessary for each geometric setup after repositioning of the system's components; the resolution losses due to the lack of recalibration are worse for the HR setup (voxel size = 18.4 μm). The integrated on-line recalibration algorithm of the Xalt scanner allowed to perform the recalibration quickly, by restoring the spatial resolution of the system to the reference resolution obtained after the initial (off-line) calibration. Copyright © 2011 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Novel Anaerobic Wastewater Treatment System for Energy Generation at Forward Operating Bases

DTIC Science & Technology

2016-08-01

AnMBR) technology with clinoptilolite ion exchange and GreenBox™ ammonia electrolysis. The system generates both methane and hydrogen fuels...experimental setup. ................................................ 21 Figure 10. Methane phase semi batch experimental setup, a total of three reactors were...set up for PS + solid, Bioc and ADS methane phase reactors. .................... 21 Figure 11. Dried PS solid for the control, Bioc blend for the

Characterization of DUT impedance in immunity test setups

NASA Astrophysics Data System (ADS)

Hassanpour Razavi, Seyyed Ali; Frei, Stephan

2016-09-01

Several immunity test procedures for narrowband radiated electromagnetic energy are available for automotive components. The ISO 11452 series describes the most commonly used test methods. The absorber line shielded enclosure (ALSE) is often considered as the most reliable method. However, testing with the bulk current injection (BCI) can be done with less efforts and is often preferred. As the test setup in both procedures is quite similar, there were several trials for finding appropriate modifications to the BCI in order to increase the matching to the ALSE. However, the lack of knowledge regarding the impedance of the tested component, makes it impossible to find the equivalent current to be injected by the BCI and a good match cannot be achieved. In this paper, three approaches are proposed to estimate the termination impedance indirectly by using different current probes.

6DOF Testing of the SLS Inertial Navigation Unit

NASA Technical Reports Server (NTRS)

Geohagan, Kevin W.; Bernard, William P.; Oliver, T. Emerson; Strickland, Dennis J.; Leggett, Jared O.

2018-01-01

The Navigation System on the NASA Space Launch System (SLS) Block 1 vehicle performs initial alignment of the Inertial Navigation System (INS) navigation frame through gyrocompass alignment (GCA). In lieu of direct testing of GCA accuracy in support of requirement verification, the SLS Navigation Team proposed and conducted an engineering test to, among other things, validate the GCA performance and overall behavior of the SLS INS model through comparison with test data. This paper will detail dynamic hardware testing of the SLS INS, conducted by the SLS Navigation Team at Marshall Space Flight Center's 6DOF Table Facility, in support of GCA performance characterization and INS model validation. A 6-DOF motion platform was used to produce 6DOF pad twist and sway dynamics while a simulated SLS flight computer communicated with the INS. Tests conducted include an evaluation of GCA algorithm robustness to increasingly dynamic pad environments, an examination of GCA algorithm stability and accuracy over long durations, and a long-duration static test to gather enough data for Allan Variance analysis. Test setup, execution, and data analysis will be discussed, including analysis performed in support of SLS INS model validation.

Micrometeorite Impact Test of Flex Solar Array Coupon

NASA Technical Reports Server (NTRS)

Wright, K. H.; Schneider, T. A.; Vaughn, J. A.; Hoang, B.; Wong, F.; Gardiner, G.

2016-01-01

Spacecraft with solar arrays operate throughout the near earth environment and are planned for outer planet missions. An often overlooked test condition for solar arrays that is applicable to these missions is micrometeoroid impacts and possibly electrostatic discharge (ESD) events resulting from these impacts. NASA Marshall Space Flight Center (MSFC) is partnering with Space Systems/Loral, LLC (SSL) to examine the results of simulated micrometeoroid impacts on the electrical performance of an advanced, lightweight flexible solar array design. The test is performed at MSFC's Micro Light Gas Gun Facility with SSL-provided coupons. Multiple impacts were induced at various locations on a powered test coupon under different string voltage (0V-150V) and string current (1.1A - 1.65A) conditions. The setup, checkout, and results from the impact testing are discussed.

Cryogenic Autogenous Pressurization Testing for Robotic Refueling Mission 3

NASA Technical Reports Server (NTRS)

Boyle, R.; DiPirro, M.; Tuttle, J.; Francis, J.; Mustafi, S.; Li, X.; Barfknecht, P.; DeLee, C. H.; McGuire, J.

2015-01-01

A wick-heater system has been selected for use to pressurize the Source Dewar of the Robotic Refueling Mission Phase 3 on-orbit cryogen transfer experiment payload for the International Space Station. Experimental results of autogenous pressurization of liquid argon and liquid nitrogen using a prototype wick-heater system are presented. The wick-heater generates gas to increase the pressure in the tank while maintaining a low bulk fluid temperature. Pressurization experiments were performed in 2013 to characterize the performance of the wick heater. This paper describes the experimental setup, pressurization results, and analytical model correlations.

The simplest possible design for a KB microfocus mirror system?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Collins, S. P., E-mail: steve.collins@diamond.ac.uk; Scott, S. M.; Hawkins, D. M.

2016-07-27

We report a design for a Kirkpatrick-Baez (KB) microfocussing mirror system. The main components are described, with emphasis on a ‘tripod’ manipulator, where we outline the required coordinate transformation calculations. The merit of this device lies in its simplicity of design, minimal degrees of freedom, and speed and ease of setup on a beamline. Test results and an example of the mirrors in use on Diamond Beamline I16, showing a high-resolution polar domain map of KTiOPO{sub 4} with a spot size of 1.25 µm × 1.5 µm, are presented.

NASA supercritical laminar flow control airfoil experiment

NASA Technical Reports Server (NTRS)

Harvey, W. D.

1982-01-01

The design and goals of experimental investigations of supercritical LFC airfoils conducted in the NASA Langley 8-ft Transonic Pressure Tunnel beginning in March 1982 are reviewed. Topics addressed include laminarization aspects; flow-quality requirements; simulation of flight parameters; the setup of screens, honeycomb, and sonic throat; the design cycle; theoretical pressure distributions and shock-free limits; drag divergence and stability analysis; and the LFC suction system. Consideration is given to the LFC airfoil model, the air-flow control system, airfoil-surface instrumentation, liner design and hardware, and test options. Extensive diagrams, drawings, graphs, photographs, and tables of numerical data are provided.

Sensitivity Study of the Wall Interference Correction System (WICS) for Rectangular Tunnels

NASA Technical Reports Server (NTRS)

Walker, Eric L.; Everhart, Joel L.; Iyer, Venkit

2001-01-01

An off-line version of the Wall Interference Correction System (WICS) has been implemented for the NASA Langley National Transonic Facility. The correction capability is currently restricted to corrections for solid wall interference in the model pitch plane for Mach numbers less than 0.45 due to a limitation in tunnel calibration data. A study to assess output sensitivity to measurement uncertainty was conducted to determine standard operational procedures and guidelines to ensure data quality during the testing process. Changes to the current facility setup and design recommendations for installing the WICS code into a new facility are reported.

Validation of an automatic system (DoubleCage) for detecting the location of animals during preference tests.

PubMed

Tsai, P P; Nagelschmidt, N; Kirchner, J; Stelzer, H D; Hackbarth, H

2012-01-01

Preference tests have often been performed for collecting information about animals' acceptance of environmental refinement objects. In numerous published studies animals were individually tested during preference experiments, as it is difficult to observe group-housed animals with an automatic system. Thus, videotaping is still the most favoured method for observing preferences of socially-housed animals. To reduce the observation workload and to be able to carry out preference testing of socially-housed animals, an automatic recording system (DoubleCage) was developed for determining the location of group-housed animals in a preference test set-up. This system is able to distinguish the transition of individual animals between two cages and to record up to 16 animals at the same time (four animals per cage). The present study evaluated the reliability of the DoubleCage system. The data recorded by the DoubleCage program and the data obtained by human observation were compared. The measurements of the DoubleCage system and manual observation of the videotapes are comparable and significantly correlated (P < 0.0001) with good agreement. Using the DoubleCage system enables precise and reliable recording of the preferences of group-housed animals and a considerable reduction of animal observation time.

Percentage depth dose calculation accuracy of model based algorithms in high energy photon small fields through heterogeneous media and comparison with plastic scintillator dosimetry

PubMed Central

Mani, Ganesh Kadirampatti; Karunakaran, Kaviarasu

2016-01-01

Small fields smaller than 4×4 cm2 are used in stereotactic and conformal treatments where heterogeneity is normally present. Since dose calculation accuracy in both small fields and heterogeneity often involves more discrepancy, algorithms used by treatment planning systems (TPS) should be evaluated for achieving better treatment results. This report aims at evaluating accuracy of four model‐based algorithms, X‐ray Voxel Monte Carlo (XVMC) from Monaco, Superposition (SP) from CMS‐Xio, AcurosXB (AXB) and analytical anisotropic algorithm (AAA) from Eclipse are tested against the measurement. Measurements are done using Exradin W1 plastic scintillator in Solid Water phantom with heterogeneities like air, lung, bone, and aluminum, irradiated with 6 and 15 MV photons of square field size ranging from 1 to 4 cm2. Each heterogeneity is introduced individually at two different depths from depth‐of‐dose maximum (Dmax), one setup being nearer and another farther from the Dmax. The central axis percentage depth‐dose (CADD) curve for each setup is measured separately and compared with the TPS algorithm calculated for the same setup. The percentage normalized root mean squared deviation (%NRMSD) is calculated, which represents the whole CADD curve's deviation against the measured. It is found that for air and lung heterogeneity, for both 6 and 15 MV, all algorithms show maximum deviation for field size 1×1 cm2 and gradually reduce when field size increases, except for AAA. For aluminum and bone, all algorithms' deviations are less for 15 MV irrespective of setup. In all heterogeneity setups, 1×1 cm2 field showed maximum deviation, except in 6 MV bone setup. All algorithms in the study, irrespective of energy and field size, when any heterogeneity is nearer to Dmax, the dose deviation is higher compared to the same heterogeneity far from the Dmax. Also, all algorithms show maximum deviation in lower‐density materials compared to high‐density materials. PACS numbers: 87.53.Bn, 87.53.kn, 87.56.bd, 87.55.Kd, 87.56.jf PMID:26894345

Development of a frameless stereotactic radiosurgery system based on real-time 6D position monitoring and adaptive head motion compensation

NASA Astrophysics Data System (ADS)

Wiersma, Rodney D.; Wen, Zhifei; Sadinski, Meredith; Farrey, Karl; Yenice, Kamil M.

2010-01-01

Stereotactic radiosurgery delivers radiation with great spatial accuracy. To achieve sub-millimeter accuracy for intracranial SRS, a head ring is rigidly fixated to the skull to create a fixed reference. For some patients, the invasiveness of the ring can be highly uncomfortable and not well tolerated. In addition, placing and removing the ring requires special expertise from a neurosurgeon, and patient setup time for SRS can often be long. To reduce the invasiveness, hardware limitations and setup time, we are developing a system for performing accurate head positioning without the use of a head ring. The proposed method uses real-time 6D optical position feedback for turning on and off the treatment beam (gating) and guiding a motor-controlled 3D head motion compensation stage. The setup consists of a central control computer, an optical patient motion tracking system and a 3D motion compensation stage attached to the front of the LINAC couch. A styrofoam head cast was custom-built for patient support and was mounted on the compensation stage. The motion feedback of the markers was processed by the control computer, and the resulting motion of the target was calculated using a rigid body model. If the target deviated beyond a preset position of 0.2 mm, an automatic position correction was performed with stepper motors to adjust the head position via the couch mount motion platform. In the event the target deviated more than 1 mm, a safety relay switch was activated and the treatment beam was turned off. The feasibility of the concept was tested using five healthy volunteers. Head motion data were acquired with and without the use of motion compensation over treatment times of 15 min. On average, test subjects exceeded the 0.5 mm tolerance 86% of the time and the 1.0 mm tolerance 45% of the time without motion correction. With correction, this percentage was reduced to 5% and 2% for the 0.5 mm and 1.0 mm tolerances, respectively.

Harsh environment fiber optic connectors/testing

NASA Astrophysics Data System (ADS)

Parker, Douglas A.

2014-09-01

Fiber optic systems are used frequently in military, aerospace and commercial aviation programs. There is a long history of implementing fiber optic data transfer for aircraft control, for harsh environment use in local area networks and more recently for in-flight entertainment systems. The advantages of fiber optics include high data rate capacity, low weight, immunity to EMI/RFI, and security from signal tapping. Technicians must be trained particularly to install and maintain fiber systems, but it is not necessarily more difficult than wire systems. However, the testing of the fiber optic interconnection system must be conducted in a standardized manner to assure proper performance. Testing can be conducted with slight differences in the set-up and procedure that produce significantly different test results. This paper reviews various options of interconnect configurations and discusses how these options can affect the performance, maintenance required and longevity of a fiber optic system, depending on the environment. Proper test methods are discussed. There is a review of the essentials of proper fiber optic testing and impact of changing such test parameters as input launch conditions, wavelength considerations, power meter options and the basic methods of testing. This becomes important right from the start when the supplier test data differs from the user's data check upon receiving the product. It also is important in periodic testing. Properly conducting the fiber optic testing will eliminate confusion and produce meaningful test results for a given harsh environment application.

Monitoring Plant Drought Stress Response Using Terahertz Time-Domain Spectroscopy[C][W

PubMed Central

Born, Norman; Behringer, David; Liepelt, Sascha; Beyer, Sarah; Schwerdtfeger, Michael; Ziegenhagen, Birgit; Koch, Martin

2014-01-01

We present a novel measurement setup for monitoring changes in leaf water status using nondestructive terahertz time-domain spectroscopy (THz-TDS). Previous studies on a variety of plants showed the principal applicability of THz-TDS. In such setups, decreasing leaf water content directly correlates with increasing THz transmission. Our new system allows for continuous, nondestructive monitoring of the water status of multiple individual plants each at the same constant leaf position. It overcomes previous drawbacks, which were mainly due to the necessity of relocating the plants. Using needles of silver fir (Abies alba) seedlings as test subjects, we show that the transmission varies along the main axis of a single needle due to a variation in thickness. Therefore, the relocation of plants during the measuring period, which was necessary in the previous THz-TDS setups, should be avoided. Furthermore, we show a highly significant correlation between gravimetric water content and respective THz transmission. By monitoring the relative change in transmission, we were able to narrow down the permanent wilting point of the seedlings. Thus, we established groups of plants with well-defined levels of water stress that could not be detected visually. This opens up the possibility for a broad range of genetic and physiological experiments. PMID:24501000

Active Optical Zoom for Tracking

DTIC Science & Technology

2008-09-01

optical system. 2. Current Setup Deformable Flat Two Deformable Flat Figure 1. Zemax lens design layout and experimental layout on the...optical bench. Figure 1 is a ZEMAX design and setup on the optical bench of two Deformable Mirrors (DMs) from OKO technologies. These mirrors have

Development of a New Optical Measuring Set-Up

NASA Astrophysics Data System (ADS)

Miroshnichenko, I. P.; Parinov, I. A.

2018-06-01

The paper proposes a description of the developed optical measuring set-up for the contactless recording and processing of measurement results for small spatial (linear and angular) displacements of control surfaces based on the use of laser technologies and optical interference methods. The proposed set-up is designed to solve all the arising measurement tasks in the study of the physical and mechanical properties of new materials and in the process of diagnosing the state of structural materials by acoustic active methods of nondestructive testing. The structure of the set-up, its constituent parts are described, and the features of construction and functioning during measurements are discussed. New technical solutions for the implementation of the components of the set-up under consideration are obtained. The purpose and description of the original specialized software, used to perform a priori analysis of measurement results, are present, while performing measurements, for a posteriori analysis of measurement results. Moreover, the influences of internal and external disturbance effects on the measurement results and correcting measurement results directly in their implementation are determined. The technical solutions, used in the set-up, are protected by the patents of the Russian Federation for inventions, and software is protected by the certificates of state registration of computer programs. The proposed set-up is intended for use in instrumentation, mechanical engineering, shipbuilding, aviation, energy sector, etc.

PILOT-SCALE EVALUATION OF ENGINEERED BARIER SYSTEMS FOR THE YUCCA MOUNTAIN PROJECT

DOE Office of Scientific and Technical Information (OSTI.GOV)

S.W. Webb; J.T. George; R.E. Finley

This paper describes two quarter-scale experiments (1.4 m diameter) and associated numerical analyses on granular backfill engineered barrier systems in support of the Yucca Mountain Project for the potential repository. The two configurations include a sloped capillary barrier and a plain backfill. The tests involve application of dyed water as a constant line infiltration source along the top of the test set-up, monitoring water movement through the test, and measuring water exiting the experiments. A complete water balance estimate is made for each test, and observed water movement is compared with (1) detailed numerical analyses conducted using the TOUGH2 codemore » for unsaturated flow in porous media and (2) posttest observations. The results of the testing and analyses show that for the injection rates and configuration applied, the capillary barrier design diverts a significant amount of all injected water and the TOUGH2 pretest predictions show qualitative and quantitative agreement with the experimental data.« less

Writing executable assertions to test flight software

NASA Technical Reports Server (NTRS)

Mahmood, A.; Andrews, D. M.; Mccluskey, E. J.

1984-01-01

An executable assertion is a logical statement about the variables or a block of code. If there is no error during execution, the assertion statement results in a true value. Executable assertions can be used for dynamic testing of software. They can be employed for validation during the design phase, and exception and error detection during the operation phase. The present investigation is concerned with the problem of writing executable assertions, taking into account the use of assertions for testing flight software. They can be employed for validation during the design phase, and for exception handling and error detection during the operation phase The digital flight control system and the flight control software are discussed. The considered system provides autopilot and flight director modes of operation for automatic and manual control of the aircraft during all phases of flight. Attention is given to techniques for writing and using assertions to test flight software, an experimental setup to test flight software, and language features to support efficient use of assertions.

The Development of an Optically Active Laser Schlieren System with Application to High Pressure Solid Propellant Combustion.

DTIC Science & Technology

1975-09-01

mass diffusion in the immediate region 13 wmmmm mm/mmn*****^^1 «•PIII^ BPP of the combustion zone remain major points of disagreement for many...setup (S2-2f2a S3 = 2f3 ) virtual image I • (9/2 f3 - i/2f2 ) — Fig.12 Virtual image setup(S2 =0.5 f2 aS3 = 3f3) 38 h v. / V image f + obje

Optimizing and Evaluating an Integrated SPECT-CmT System Dedicated to Improved 3-D Breast Cancer Imaging

DTIC Science & Technology

2010-05-01

mammography," (2008). 4. H. M. Warren-Forward and L. Duggan, "Towards in vivo TLD dosimetry in mammography," Br J Radiol 77, 426-432 (2004). 5. X. Wu, G...thermoluminescent detectors ( TLDs ) were used in the experiments but, after consultation with experts in the field of radiation dosimetry , it was decided...prohibitively expensive to use TLDs for the various study setups and that the dosimetry results from one setup could be extended to similar setups that

Method and apparatus for checking the stability of a setup for making reflection type holograms

NASA Technical Reports Server (NTRS)

Lackner, H. G. (Inventor)

1974-01-01

A method and apparatus are described for checking the stability of a setup for recording reflection-type (white light) holograms. Two sets of interference fringes are simultaneously obtained, one giving information about coherence and stability of the setup alone and the other demonstrating coherence of the entire system, including the holographic recording plate. Special emphasis is given to the stability of the plate, due to the fact that any minute vibration might severely degrade or completely destroy the recording.

Torque Loss After Miniscrew Placement: An In-Vitro Study Followed by a Clinical Trial.

PubMed

Migliorati, Marco; Drago, Sara; Barberis, Fabrizio; Schiavetti, Irene; Dalessandri, Domenico; Benedicenti, Stefano; Biavati, Armando Silvestrini

2016-01-01

To evaluate torque loss a week after insertion, both in an in vivo and an in vitro experimental setup were designed. In the in vivo setup a total of 29 miniscrews were placed in 20 patients who underwent orthodontic treatment. Maximum insertion torque (MIT) was evaluated at insertion time (T1). A week later, insertion torque was measured again by applying a quarter turn (T2); no load was applied on the screw during the first week. In the in vitro setup a total of 20 miniscrews were placed in pig rib bone samples. MIT was evaluated at insertion time (T1). Bone samples were kept in saline solution and controlled environment for a week during which the solution was refreshed every day. Afterwards, torque was measured again by applying a quarter turn (T2). The comparison of MIT over time was done calculating the percentage difference of the torque values between pre- and post-treatment and using the parametric two independent samples t-test or the non-parametric Mann-Whitney test. After a week unloaded miniscrews showed a mean loss of rotational torque of 36.3% and 40.9% in in vitro and in in vivo conditions, respectively. No statistical differences were found between the two different setups. Torque loss was observed after the first week in both study models; in vitro experimental setup provided a reliable study model for studying torque variation during the first week after insertion.

Torque Loss After Miniscrew Placement: An In-Vitro Study Followed by a Clinical Trial

PubMed Central

Migliorati, Marco; Drago, Sara; Barberis, Fabrizio; Schiavetti, Irene; Dalessandri, Domenico; Benedicenti, Stefano; Biavati, Armando Silvestrini

2016-01-01

To evaluate torque loss a week after insertion, both in an in vivo and an in vitro experimental setup were designed. In the in vivo setup a total of 29 miniscrews were placed in 20 patients who underwent orthodontic treatment. Maximum insertion torque (MIT) was evaluated at insertion time (T1). A week later, insertion torque was measured again by applying a quarter turn (T2); no load was applied on the screw during the first week. In the in vitro setup a total of 20 miniscrews were placed in pig rib bone samples. MIT was evaluated at insertion time (T1). Bone samples were kept in saline solution and controlled environment for a week during which the solution was refreshed every day. Afterwards, torque was measured again by applying a quarter turn (T2). The comparison of MIT over time was done calculating the percentage difference of the torque values between pre- and post-treatment and using the parametric two independent samples t-test or the non-parametric Mann–Whitney test. After a week unloaded miniscrews showed a mean loss of rotational torque of 36.3% and 40.9% in in vitro and in in vivo conditions, respectively. No statistical differences were found between the two different setups. Torque loss was observed after the first week in both study models; in vitro experimental setup provided a reliable study model for studying torque variation during the first week after insertion. PMID:27386011

Computational fluid dynamics modeling of laboratory flames and an industrial flare.

PubMed

Singh, Kanwar Devesh; Gangadharan, Preeti; Chen, Daniel H; Lou, Helen H; Li, Xianchang; Richmond, Peyton

2014-11-01

A computational fluid dynamics (CFD) methodology for simulating the combustion process has been validated with experimental results. Three different types of experimental setups were used to validate the CFD model. These setups include an industrial-scale flare setups and two lab-scale flames. The CFD study also involved three different fuels: C3H6/CH/Air/N2, C2H4/O2/Ar and CH4/Air. In the first setup, flare efficiency data from the Texas Commission on Environmental Quality (TCEQ) 2010 field tests were used to validate the CFD model. In the second setup, a McKenna burner with flat flames was simulated. Temperature and mass fractions of important species were compared with the experimental data. Finally, results of an experimental study done at Sandia National Laboratories to generate a lifted jet flame were used for the purpose of validation. The reduced 50 species mechanism, LU 1.1, the realizable k-epsilon turbulence model, and the EDC turbulence-chemistry interaction model were usedfor this work. Flare efficiency, axial profiles of temperature, and mass fractions of various intermediate species obtained in the simulation were compared with experimental data and a good agreement between the profiles was clearly observed. In particular the simulation match with the TCEQ 2010 flare tests has been significantly improved (within 5% of the data) compared to the results reported by Singh et al. in 2012. Validation of the speciated flat flame data supports the view that flares can be a primary source offormaldehyde emission.

Simulation and control for telerobots in space medicine

NASA Astrophysics Data System (ADS)

Haidegger, Tamás; Kovács, Levente; Precup, Radu-Emil; Benyó, Balázs; Benyó, Zoltán; Preitl, Stefan

2012-12-01

Human space exploration is continuously advancing despite the current financial difficulties, and the new missions are targeting the Moon and the Mars with more effective human-robot collaborative systems. The continuous development of robotic technology should lead to the advancement of automated technology, including space medicine. Telesurgery has already proved its effectiveness through various telemedicine procedures on Earth, and it has the potential to provide medical assistance in space as well. Aeronautical agencies have already conducted numerous experiments and developed various setups to push the boundaries of teleoperation under extreme conditions. Different control schemes have been proposed and tested to facilitate and enhance telepresence and to ensure transparency, sufficient bandwidth and latency-tolerance. This paper focuses on the modeling of a generic telesurgery setup, supported by a cascade control approach. The minimalistic models were tested with linear and PID-fuzzy control options to provide a simple, universal and scalable solution for the challenges of telesurgery over large distances. In our simulations, the control structures were capable of providing good dynamic performance indices and robustness with respect to the gain in the human operator model. This is a promising result towards the support of future teleoperational missions.

Kilovoltage cone-beam CT imaging dose during breast radiotherapy: A dose comparison between a left and right breast setup

DOE Office of Scientific and Technical Information (OSTI.GOV)

Quinn, Alexandra, E-mail: Alexandra.quinn@health.nsw.gov.au; Centre for Medical Radiation Physics, University of Wollongong, NSW; Liverpool and Macarthur Cancer Therapy Centres, NSW

2014-07-01

The purpose of this study was to investigate the delivered dose from a kilovoltage cone-beam computed tomography (kV-CBCT) acquired in breast treatment position for a left and right breast setup. The dose was measured with thermoluminescent dosimeters positioned within a female anthropomorphic phantom at organ locations. Imaging was performed on an Elekta Synergy XVI system with the phantom setup on a breast board. The image protocol involved 120 kVp, 140 mAs, and a 270° arc rotation clockwise 0° to 270° for the left breast setup and 270° to 180° for the right breast setup (maximum arc rotations possible). The dosemore » delivered to the left breast, right breast, and heart was 5.1 mGy, 3.9 mGy, and 4.0 mGy for the left breast setup kV-CBCT, and 6.4 mGy, 6.0 mGy, and 4.8 mGy for the right breast setup kV-CBCT, respectively. The rotation arc of the kV-CBCT influenced the dose delivered, with the right breast setup kV-CBCT found to deliver a dose of up to 4 mGy or 105% higher to the treated breast′s surface in comparison with the left breast setup. This is attributed to the kV-CBCT source being more proximal to the anterior of the phantom for a right breast setup, whereas the source is more proximal to the posterior of the patient for a left-side scan.« less

Poster - 33: Dosimetry Comparison of Prone Breast Forward and Inverse Treatment planning considering daily setup variations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jiang, Runqing; Zhan, Lixin; Osei, Ernest

2016-08-15

Introduction: The purpose of this study is to investigate the effects of daily setup variations on prone breast forward field-in-field (FinF) and inverse IMRT treatment planning. Methods: Rando Phantom (Left breast) and Pixy phantom (Right breast) were built and CT scanned in prone position. The treatment planning (TP) is performed in Eclipse TP system. Forward FinF plan and inverse IMRT plan were created to satisfy the CTV coverage and OARs criteria. The daily setup variations were assumed to be 5 mm at left-right, superior-inferior, and anterior-posterior directions. The DVHs of CTV coverage and OARs were compared for both forward FinFmore » plan and inverse IMRT plans due to 5mm setup variation. Results and Discussions: DVHs of CTV coverage had fewer variations for 5m setup variation for forward FinF and inverse IMRT plan for both phantoms. However, for the setup variations in the left-right direction, the DVH of CTV coverage of IMRT plan showed the worst variation due to lateral setup variation for both phantoms. For anterior-posterior variation, the CTV could not get full coverage when the breast chest wall is shallow; however, with the guidance of MV imaging, breast chest wall will be checked during the MV imaging setup. So the setup variations have more effects on inverse IMRT plan, compared to forward FinF plan, especially in the left-right direction. Conclusions: The Forward FinF plan was recommended clinically considering daily setup variation.« less

Investigation of aeroelastic stability phenomena of a helicopter by in-flight shake test

NASA Technical Reports Server (NTRS)

Miao, W. L.; Edwards, T.; Brandt, D. E.

1976-01-01

The analytical capability of the helicopter stability program is discussed. The parameters which are found to be critical to the air resonance characteristics of the soft in-plane hingeless rotor systems are detailed. A summary of two model test programs, a 1/13.8 Froude-scaled BO-105 model and a 1.67 meter (5.5 foot) diameter Froude-scaled YUH-61A model, are presented with emphasis on the selection of the final parameters which were incorporated in the full scale YUH-61A helicopter. Model test data for this configuration are shown. The actual test results of the YUH-61A air resonance in-flight shake test stability are presented. Included are a concise description of the test setup, which employs the Grumman Automated Telemetry System (ATS), the test technique for recording in-flight stability, and the test procedure used to demonstrate favorable stability characteristics with no in-plane damping augmentation (lag damper removed). The data illustrating the stability trend of air resonance with forward speed and the stability trend of ground resonance for percent airborne are presented.

Thermoelectrics as elements of hybrid-electric vehicle thermal energy systems

NASA Astrophysics Data System (ADS)

Headings, Leon; Washington, Gregory; Jaworski, Christopher M.

2008-03-01

Despite vast technological improvements, the traditional internal combustion powered vehicle still achieves only 25- 30% efficiency, with the remainder lost primarily as heat. While the load leveling offered by hybrid-electric vehicle technology helps to improve this overall efficiency, part of the efficiency gains are achieved by making new systems such as regenerative braking viable. In a similar fashion, thermoelectric (TE) energy recovery has long been considered for traditional vehicles with mixed results, but little has been done to consider thermoelectrics in the framework of the unique energy systems of hybrid vehicles. Systems that may not have been viable or even possible with traditional vehicles may offer improvements to system efficiency as well as emissions, vehicle durability, passenger comfort, and cost. This research describes a simulation developed for evaluating and optimizing thermoelectric energy recovery systems and results for four different system configurations. Two novel system configurations are presented which offer the potential for additional benefits such as emissions reduction that will soon be quantified. In addition, a test setup is presented which was constructed for the testing and validation of various thermoelectric recovery systems. Actual test performance was near the expected theoretical performance and supported the conclusions reached from the computer simulations.

KSC-07pd1499

NASA Image and Video Library

2007-06-13

KENNEDY SPACE CENTER, FLA. -- United Space Alliance employees prepare test articles to be used in wind tunnel testing by NASA to collect data for analysis of the detached Flexible Insulation Blanket, or FIB, on Atlantis. A tear occurred in an area of the OMS pod on Atlantis during launch of mission STS-117 on June 8, 2007. The test articles each feature three tiles (Low Temperature Reusable Surface Insulation, or LRSI) affixed next to two FIB blankets, simulating the thermal protection system set-up on Atlantis' OMS pod in the vicinity of the in-flight anomaly. These test articles will be flown to Texas the morning of June 14. The TPS team at KSC has also provided a total of 22 FIB samples for other testing and analysis. Repair is under consideration following testing at KSC and Houston. Photo credit: NASA/Amanda Diller

KSC-07pd1498

NASA Image and Video Library

2007-06-13

KENNEDY SPACE CENTER, FLA. -- United Space Alliance employees prepare test articles to be used in wind tunnel testing by NASA to collect data for analysis of the detached Flexible Insulation Blanket, or FIB, on Atlantis. A tear occurred in an area of the OMS pod on Atlantis during launch of mission STS-117 on June 8, 2007. The test articles each feature three tiles (Low Temperature Reusable Surface Insulation, or LRSI) affixed next to two FIB blankets, simulating the thermal protection system set-up on Atlantis' OMS pod in the vicinity of the in-flight anomaly. These test articles will be flown to Texas the morning of June 14. The TPS team at KSC has also provided a total of 22 FIB samples for other testing and analysis. Repair is under consideration following testing at KSC and Houston. Photo credit: NASA/Amanda Diller

KSC-07pd1497

NASA Image and Video Library

2007-06-13

KENNEDY SPACE CENTER, FLA. -- United Space Alliance employees prepare test articles to be used in wind tunnel testing by NASA to collect data for analysis of the detached Flexible Insulation Blanket, or FIB, on Atlantis. A tear occurred in an area of the OMS pod on Atlantis during launch of mission STS-117 on June 8, 2007. The test articles each feature three tiles (Low Temperature Reusable Surface Insulation, or LRSI) affixed next to two FIB blankets, simulating the thermal protection system set-up on Atlantis' OMS pod in the vicinity of the in-flight anomaly. These test articles will be flown to Texas the morning of June 14. The TPS team at KSC has also provided a total of 22 FIB samples for other testing and analysis. Repair is under consideration following testing at KSC and Houston. Photo credit: NASA/Amanda Diller

KSC-07pd1501

NASA Image and Video Library

2007-06-13

KENNEDY SPACE CENTER, FLA. -- United Space Alliance employees prepare test articles to be used in wind tunnel testing by NASA to collect data for analysis of the detached Flexible Insulation Blanket, or FIB, on Atlantis. A tear occurred in an area of the OMS pod on Atlantis during launch of mission STS-117 on June 8, 2007. The test articles each feature three tiles (Low Temperature Reusable Surface Insulation, or LRSI) affixed next to two FIB blankets, simulating the thermal protection system set-up on Atlantis' OMS pod in the vicinity of the in-flight anomaly. These test articles will be flown to Texas the morning of June 14. The TPS team at KSC has also provided a total of 22 FIB samples for other testing and analysis. Repair is under consideration following testing at KSC and Houston. Photo credit: NASA/Amanda Diller

KSC-07pd1496

NASA Image and Video Library

2007-06-13

KENNEDY SPACE CENTER, FLA. -- A United Space Alliance employee prepares a test article that will be used in wind tunnel testing by NASA to collect data for analysis of the detached Flexible Insulation Blanket, or FIB, on Atlantis. A tear occurred in an area of the OMS pod on Atlantis during launch of mission STS-117 on June 8, 2007. The test articles each feature three tiles (Low Temperature Reusable Surface Insulation, or LRSI) affixed next to two FIB blankets, simulating the thermal protection system set-up on Atlantis' OMS pod in the vicinity of the in-flight anomaly. These test articles will be flown to Texas the morning of June 14. The TPS team at KSC has also provided a total of 22 FIB samples for other testing and analysis. Repair is under consideration following testing at KSC and Houston. Photo credit: NASA/Amanda Diller

KSC-07pd1500

NASA Image and Video Library

2007-06-13

KENNEDY SPACE CENTER, FLA. -- United Space Alliance employees prepare test articles to be used in wind tunnel testing by NASA to collect data for analysis of the detached Flexible Insulation Blanket, or FIB, on Atlantis. A tear occurred in an area of the OMS pod on Atlantis during launch of mission STS-117 on June 8, 2007. The test articles each feature three tiles (Low Temperature Reusable Surface Insulation, or LRSI) affixed next to two FIB blankets, simulating the thermal protection system set-up on Atlantis' OMS pod in the vicinity of the in-flight anomaly. These test articles will be flown to Texas the morning of June 14. The TPS team at KSC has also provided a total of 22 FIB samples for other testing and analysis. Repair is under consideration following testing at KSC and Houston. Photo credit: NASA/Amanda Diller

Automatic detection of patient identification and positioning errors in radiation therapy treatment using 3-dimensional setup images.

PubMed

Jani, Shyam S; Low, Daniel A; Lamb, James M

2015-01-01

To develop an automated system that detects patient identification and positioning errors between 3-dimensional computed tomography (CT) and kilovoltage CT planning images. Planning kilovoltage CT images were collected for head and neck (H&N), pelvis, and spine treatments with corresponding 3-dimensional cone beam CT and megavoltage CT setup images from TrueBeam and TomoTherapy units, respectively. Patient identification errors were simulated by registering setup and planning images from different patients. For positioning errors, setup and planning images were misaligned by 1 to 5 cm in the 6 anatomical directions for H&N and pelvis patients. Spinal misalignments were simulated by misaligning to adjacent vertebral bodies. Image pairs were assessed using commonly used image similarity metrics as well as custom-designed metrics. Linear discriminant analysis classification models were trained and tested on the imaging datasets, and misclassification error (MCE), sensitivity, and specificity parameters were estimated using 10-fold cross-validation. For patient identification, our workflow produced MCE estimates of 0.66%, 1.67%, and 0% for H&N, pelvis, and spine TomoTherapy images, respectively. Sensitivity and specificity ranged from 97.5% to 100%. MCEs of 3.5%, 2.3%, and 2.1% were obtained for TrueBeam images of the above sites, respectively, with sensitivity and specificity estimates between 95.4% and 97.7%. MCEs for 1-cm H&N/pelvis misalignments were 1.3%/5.1% and 9.1%/8.6% for TomoTherapy and TrueBeam images, respectively. Two-centimeter MCE estimates were 0.4%/1.6% and 3.1/3.2%, respectively. MCEs for vertebral body misalignments were 4.8% and 3.6% for TomoTherapy and TrueBeam images, respectively. Patient identification and gross misalignment errors can be robustly and automatically detected using 3-dimensional setup images of different energies across 3 commonly treated anatomical sites. Copyright © 2015 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

Dynamic response tests of inertial and optical wind-tunnel model attitude measurement devices

NASA Technical Reports Server (NTRS)

Buehrle, R. D.; Young, C. P., Jr.; Burner, A. W.; Tripp, J. S.; Tcheng, P.; Finley, T. D.; Popernack, T. G., Jr.

1995-01-01

Results are presented for an experimental study of the response of inertial and optical wind-tunnel model attitude measurement systems in a wind-off simulated dynamic environment. This study is part of an ongoing activity at the NASA Langley Research Center to develop high accuracy, advanced model attitude measurement systems that can be used in a dynamic wind-tunnel environment. This activity was prompted by the inertial model attitude sensor response observed during high levels of model vibration which results in a model attitude measurement bias error. Significant bias errors in model attitude measurement were found for the measurement using the inertial device during wind-off dynamic testing of a model system. The amount of bias present during wind-tunnel tests will depend on the amplitudes of the model dynamic response and the modal characteristics of the model system. Correction models are presented that predict the vibration-induced bias errors to a high degree of accuracy for the vibration modes characterized in the simulated dynamic environment. The optical system results were uncorrupted by model vibration in the laboratory setup.

Software development infrastructure for the HYBRID modeling and simulation project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Epiney, Aaron S.; Kinoshita, Robert A.; Kim, Jong Suk

One of the goals of the HYBRID modeling and simulation project is to assess the economic viability of hybrid systems in a market that contains renewable energy sources like wind. The idea is that it is possible for the nuclear plant to sell non-electric energy cushions, which absorb (at least partially) the volatility introduced by the renewable energy sources. This system is currently modeled in the Modelica programming language. To assess the economics of the system, an optimization procedure is trying to find the minimal cost of electricity production. The RAVEN code is used as a driver for the wholemore » problem. It is assumed that at this stage, the HYBRID modeling and simulation framework can be classified as non-safety “research and development” software. The associated quality level is Quality Level 3 software. This imposes low requirements on quality control, testing and documentation. The quality level could change as the application development continues.Despite the low quality requirement level, a workflow for the HYBRID developers has been defined that include a coding standard and some documentation and testing requirements. The repository performs automated unit testing of contributed models. The automated testing is achieved via an open-source python script called BuildingsP from Lawrence Berkeley National Lab. BuildingsPy runs Modelica simulation tests using Dymola in an automated manner and generates and runs unit tests from Modelica scripts written by developers. In order to assure effective communication between the different national laboratories a biweekly videoconference has been set-up, where developers can report their progress and issues. In addition, periodic face-face meetings are organized intended to discuss high-level strategy decisions with management. A second means of communication is the developer email list. This is a list to which everybody can send emails that will be received by the collective of the developers and managers involved in the project. Thirdly, to exchange documents quickly, a SharePoint directory has been set-up. SharePoint allows teams and organizations to intelligently share, and collaborate on content from anywhere.« less

Qualification of the Tropical Rainfall Measuring Mission Solar Array Deployment System

NASA Technical Reports Server (NTRS)

Lawrence, Jon

1998-01-01

The Tropical Rainfall Measuring Mission (TRMM) solar arrays are placed into orbital configuration by a complex deployment system. Its two wings each comprise twin seven square solar panels located by a twelve foot articulated boom. The four spring-driven hinge lines per wing are rate-limited by viscous dampers. The wings are stowed against the spacecraft kinematically, and released by five pyrotechnically-actuated mechanisms. Since deployment failure would be catastrophic, a total of 17 deployment tests were completed to qualify the system for the worst cast launch environment. This successful testing culminated in the flawless deployment of the solar arrays on orbit, 15 minutes after launch in November 1997. The custom gravity negation system used to perform deployment testing is modular to allow its setup in several locations, including the launch site in Japan. Both platform and height can be varied, to meet the requirements of the test configuration and the test facility. Its air pad floatation system meets tight packaging requirements, allowing installation while stowed against the spacecraft without breaking any flight interfaces, and avoiding interference during motion. This system was designed concurrently with the deployment system, to facilitate its installation, to aid in the integration of the flight system to the spacecraft, while demonstrating deployment capabilities. Critical parameters for successful testing were alignment of deployment axes and tables to gravity, alignment of table seams to minimize discontinuities, and minimizing pressure drops in the air supply system. Orbital performance was similar to that predicted by ground testing.

The Very Specific Vortex Shedding Test on VEGA Launch Vehicle

NASA Astrophysics Data System (ADS)

Leofanti, Jose Luis; Fotio, Domenico; Grillenbeck, Anton; Dillinger, Stephan; Scaccia, Aldo

2012-07-01

When tall structures are subjected to lateral wind flow, under certain conditions, vortices are shed from alternate sides of the structure inducing periodic cross wind loads on the structure. The periodic loads, in a relatively narrow and stable frequency band, can couple with the structure’s natural frequencies. To avoid this effect the VEGA Launch System (LS) comprised a decoupling device at the launch vehicle (LV) base called Anti Vortex Shedding (AVS). During the LV-Ground Segment combined test campaign in Kourou, the LV mounted on AVS was experimentally verified, including a modal characterization test, a verification under artificial operational loads and finally tested under real wind environment. The paper gives an overview on the particular aspects of test planning, the test setup preparation inside the launch pad gantry, the test performance, test results and the conclusion for the VEGA launch system’s operational readiness.

Cryo-vacuum testing of the JWST Integrated Science Instrument Module (SPIE)

NASA Technical Reports Server (NTRS)

Kimble, Randy A.; Vila, M. Begona; Van Campen, Julie; Birkmann, Stephan M.; Comber, Brian J.; Fatig, Curtis C.; Glasse, Alistair C. H.; Glazer, Stuart D.; Kelly, Douglas M.; Mann, Steven D.;

Robot Drills Holes To Relieve Excess Tire Pressures

NASA Technical Reports Server (NTRS)

Carrott, David T.

1996-01-01

Small, relatively inexpensive, remotely controlled robot called "tire assault vehicle" (TAV) developed to relieve excess tire pressures to protect ground crew, aircraft equipment, and nearby vehicles engaged in landing tests of CV-990 Landing System Research Aircraft. Reduces costs and saves time in training, maintenance, and setup related to "yellow" and "red" tire conditions. Adapted to any heavy-aircraft environment in which ground-crew safety at risk because of potential for tire explosions. Also ideal as scout vehicle for performing inspections in hazardous locations.

Implementation of an Open-Loop Rule-Based Control Strategy for a Hybrid-Electric Propulsion System On a Small RPA

DTIC Science & Technology

2011-03-01

input spindle from the engine to over tighten and apply an even greater amount of resistance to the engine shaft . Not only was this dangerous to...Mengistu, Todd Rotramel, and Matt Rippl, all of whom worked together with me to design and build the test rig for our dynamometer setup. Countless...hours were spent together planning and executing the design and building the stand itself. The AFIT machine shop crew and ENY lab techs also

SPHERES tethered formation flight testbed: advancements in enabling NASA's SPECS mission

NASA Astrophysics Data System (ADS)

Chung, Soon-Jo; Adams, Danielle; Saenz-Otero, Alvar; Kong, Edmund; Miller, David W.; Leisawitz, David; Lorenzini, Enrico; Sell, Steve

2006-06-01

This paper reports on efforts to control a tethered formation flight spacecraft array for NASA's SPECS mission using the SPHERES test-bed developed by the MIT Space Systems Laboratory. Specifically, advances in methodology and experimental results realized since the 2005 SPIE paper are emphasized. These include a new test-bed setup with a reaction wheel assembly, a novel relative attitude measurement system using force torque sensors, and modeling of non-ideal tethers to account for tether vibration modes. The nonlinear equations of motion of multi-vehicle tethered spacecraft with elastic flexible tethers are derived from Lagrange's equations. The controllability analysis indicates that both array resizing and spin-up are fully controllable by the reaction wheels and the tether motor, thereby saving thruster fuel consumption. Based upon this analysis, linear and nonlinear controllers have been successfully implemented on the tethered SPHERES testbed, and tested at the NASA MSFC's flat floor facility using two and three SPHERES configurations.

ROS-IGTL-Bridge: an open network interface for image-guided therapy using the ROS environment.

PubMed

Frank, Tobias; Krieger, Axel; Leonard, Simon; Patel, Niravkumar A; Tokuda, Junichi

2017-08-01

With the growing interest in advanced image-guidance for surgical robot systems, rapid integration and testing of robotic devices and medical image computing software are becoming essential in the research and development. Maximizing the use of existing engineering resources built on widely accepted platforms in different fields, such as robot operating system (ROS) in robotics and 3D Slicer in medical image computing could simplify these tasks. We propose a new open network bridge interface integrated in ROS to ensure seamless cross-platform data sharing. A ROS node named ROS-IGTL-Bridge was implemented. It establishes a TCP/IP network connection between the ROS environment and external medical image computing software using the OpenIGTLink protocol. The node exports ROS messages to the external software over the network and vice versa simultaneously, allowing seamless and transparent data sharing between the ROS-based devices and the medical image computing platforms. Performance tests demonstrated that the bridge could stream transforms, strings, points, and images at 30 fps in both directions successfully. The data transfer latency was <1.2 ms for transforms, strings and points, and 25.2 ms for color VGA images. A separate test also demonstrated that the bridge could achieve 900 fps for transforms. Additionally, the bridge was demonstrated in two representative systems: a mock image-guided surgical robot setup consisting of 3D slicer, and Lego Mindstorms with ROS as a prototyping and educational platform for IGT research; and the smart tissue autonomous robot surgical setup with 3D Slicer. The study demonstrated that the bridge enabled cross-platform data sharing between ROS and medical image computing software. This will allow rapid and seamless integration of advanced image-based planning/navigation offered by the medical image computing software such as 3D Slicer into ROS-based surgical robot systems.

EUSO@TurLab: An experimental replica of ISS orbits

NASA Astrophysics Data System (ADS)

Bertaina, M.; Bowaire, A.; Cambursano, S.; Caruso, R.; Contino, G.; Cotto, G.; Crivello, F.; Forza, R.; Guardone, N.; Manfrin, M.; Mignone, M.; Mulas, R.; Suino, G.; Tibaldi, P. S.

2015-03-01

The EUSO@TurLab project is an on-going activity aimed to reproduce atmospheric and luminous conditions that JEM-EUSO will encounter on its orbits around the Earth. The use of the TurLab facility, part of the Department of Physics of the University of Torino, allows the simulation of different surface conditions in a very dark and rotating environment in order to test the response of JEM-EUSO's sensors and sensitivity. The experimental setup currently in operation has been used to check the potential of the TurLab facility for the above purposes, and the acquired data will be used to test the concept of JEM-EUSO's trigger system.

Constitutive modeling of superalloy single crystals with verification testing

NASA Technical Reports Server (NTRS)

Jordan, Eric; Walker, Kevin P.

1985-01-01

The goal is the development of constitutive equations to describe the elevated temperature stress-strain behavior of single crystal turbine blade alloys. The program includes both the development of a suitable model and verification of the model through elevated temperature-torsion testing. A constitutive model is derived from postulated constitutive behavior on individual crystallographic slip systems. The behavior of the entire single crystal is then arrived at by summing up the slip on all the operative crystallographic slip systems. This type of formulation has a number of important advantages, including the prediction orientation dependence and the ability to directly represent the constitutive behavior in terms which metallurgists use in describing the micromechanisms. Here, the model is briefly described, followed by the experimental set-up and some experimental findings to date.

En face projection imaging of the human choroidal layers with tracking SLO and swept source OCT angiography methods

NASA Astrophysics Data System (ADS)

Gorczynska, Iwona; Migacz, Justin; Zawadzki, Robert J.; Sudheendran, Narendran; Jian, Yifan; Tiruveedhula, Pavan K.; Roorda, Austin; Werner, John S.

2015-07-01

We tested and compared the capability of multiple optical coherence tomography (OCT) angiography methods: phase variance, amplitude decorrelation and speckle variance, with application of the split spectrum technique, to image the choroiretinal complex of the human eye. To test the possibility of OCT imaging stability improvement we utilized a real-time tracking scanning laser ophthalmoscopy (TSLO) system combined with a swept source OCT setup. In addition, we implemented a post- processing volume averaging method for improved angiographic image quality and reduction of motion artifacts. The OCT system operated at the central wavelength of 1040nm to enable sufficient depth penetration into the choroid. Imaging was performed in the eyes of healthy volunteers and patients diagnosed with age-related macular degeneration.

An Improved SEL Test of the ADV212 Video Codec

NASA Technical Reports Server (NTRS)

Wilcox, Edward P.; Campola, Michael J.; Nadendla, Seshagiri; Kadari, Madhusudhan; Gigliuto, Robert A.

2017-01-01

Single-event effect (SEE) test data is presented on the Analog Devices ADV212. Focus is given to the test setup used to improve data quality and validate single-event latch-up (SEL) protection circuitry.

An Improved SEL Test of the ADV212 Video Codec

NASA Technical Reports Server (NTRS)

Wilcox, Edward P; Campola, Michael J.; Nadendla, Seshagiri; Kadari, Madhusudhan; Gigliuto, Robert A.

2017-01-01

Single-event effect (SEE) test data is presented on the Analog Devices ADV212. Focus is given to the test setup used to improve data quality and validate single-event latchup (SEL) protection circuitry.

A gamma-ray testing technique for spacecraft. [considering cosmic radiation effects

NASA Technical Reports Server (NTRS)

Gribov, B. S.; Repin, N. N.; Sakovich, V. A.; Sakharov, V. M.

1977-01-01

The simulated cosmic radiation effect on a spacecraft structure is evaluated by gamma ray testing in relation to structural thickness. A drawing of the test set-up is provided and measurement errors are discussed.

BEAP profiles as rapid test system for status analysis and early detection of process incidents in biogas plants.

PubMed

Refai, Sarah; Berger, Stefanie; Wassmann, Kati; Hecht, Melanie; Dickhaus, Thomas; Deppenmeier, Uwe

2017-03-01

A method was developed to quantify the performance of microorganisms involved in different digestion levels in biogas plants. The test system was based on the addition of butyrate (BCON), ethanol (ECON), acetate (ACON) or propionate (PCON) to biogas sludge samples and the subsequent analysis of CH 4 formation in comparison to control samples. The combination of the four values was referred to as BEAP profile. Determination of BEAP profiles enabled rapid testing of a biogas plant's metabolic state within 24 h and an accurate mapping of all degradation levels in a lab-scale experimental setup. Furthermore, it was possible to distinguish between specific BEAP profiles for standard biogas plants and for biogas reactors with process incidents (beginning of NH 4 + -N inhibition, start of acidification, insufficient hydrolysis and potential mycotoxin effects). Finally, BEAP profiles also functioned as a warning system for the early prediction of critical NH 4 + -N concentrations leading to a drop of CH 4 formation.

Comparison of normal and phase stepping shearographic NDE

NASA Astrophysics Data System (ADS)

Andhee, A.; Gryzagoridis, J.; Findeis, D.

2005-05-01

The paper presents results of non-destructive testing of composite main rotor helicopter blade calibration specimens using the laser based optical NDE technique known as Shearography. The tests were performed initially using the already well established near real-time non-destructive technique of Shearography, with the specimens perturbed during testing for a few seconds using the hot air from a domestic hair dryer. Subsequent to modification of the shearing device utilized in the shearographic setup, phase stepping of one of the sheared images to be captured by the CCD camera was enabled and identical tests were performed on the composite main rotor helicopter blade specimens. Considerable enhancement of the images manifesting or depicting the defects on the specimens is noted suggesting that phase stepping is a desirable enhancement technique to the traditional Shearographic setup.

Comparative analysis of international standards for the fatigue testing of posterior spinal fixation systems.

PubMed

Villa, Tomaso; La Barbera, Luigi; Galbusera, Fabio

2014-04-01

Preclinical evaluation of the long-term reliability of devices for lumbar fixation is a mandatory activity before they are put into market. The experimental setups are described in two different standards edited by the International Organization for Standardization (ISO) and the American Society for Testing Materials (ASTM), but the evaluation of the suitability of such tests to simulate the actual loading with in vivo situations has never been performed. To calculate through finite element (FE) simulations the stress in the rods of the fixator when subjected to ASTM and ISO standards. To compare the calculated stresses arising in the same fixator once it has been virtually mounted in a physiological environment and loaded with physiological forces and moments. FE simulations and validation experimental tests. FE models of the ISO and ASTM setups were created to conduct simulations of the tests prescribed by standards and calculate stresses in the rods. Validation of the simulations were performed through experimental tests; the same fixator was virtually mounted in an L2-L4 FE model of the lumbar spine and stresses in the rods were calculated when the spine was subjected to physiological forces and moments. The comparison between FE simulations and experimental tests showed good agreement between results obtained using the two methodologies, thus confirming the suitability of the FE method to evaluate stresses in the device in different loading situations. The usage of a physiological load with ASTM standard is impossible due to the extreme severity of the ASTM configuration; in this circumstance, the presence of an anterior support is suggested. Also, ISO prescriptions, although the choice of the setup correctly simulates the mechanical contribution of the discs, seem to overstress the device as compared with a physiological loading condition. Some daily activities, other than walking, can induce a further state of stress in the device that should be taken into account in setting up new experimental procedures. ISO standard loading prescriptions seems to be more severe than the expected physiological ones. The ASTM standard should be completed by including some anterior supporting device and declaring the value of the load to be imposed. Moreover, a further enhancement of standards would be simulating other movements representative of daily activities different from walking. Copyright © 2014 Elsevier Inc. All rights reserved.

Automated setup for spray assisted layer-by-layer deposition.

PubMed

Mundra, Paul; Otto, Tobias; Gaponik, Nikolai; Eychmüller, Alexander

2013-07-01

The design for a setup allowing the layer-by-layer (LbL) assembly of thin films consisting of various colloidal materials is presented. The proposed system utilizes the spray-assisted LbL approach and is capable of autonomously producing films. It provides advantages to existing LbL procedures in terms of process speed and applicability. The setup offers several features that are advantageous for routine operation like an actuated sample holder, stainless steel spraying nozzles, or an optical liquid detection system. The applicability is demonstrated by the preparation of films containing semiconductor nanoparticles, namely, CdSe∕CdS quantum dots and a polyelectolyte. The films of this type are of potential interest for applications in optoelectronic devices such as light-emitting diodes or solar cells.

Effects of cooling system parameters on heat transfer in PAFC stack. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Abdul-Aziz, Ali A.

1985-01-01

Analytical and experimental study for the effects of cooling system parameters on the heat transfer and temperature distribution in the electrode plates of a phosphoric acid fuel-cell has been conducted. An experimental set-up that simulates the operating conditions prevailing in a phosphoric-acid fuel-cell stack was designed and constructed. The set-up was then used to measure the overall heat transfer coefficient, the thermal contact resistance, and the electrode temperature distribution for two different cooling plate configurations. Two types of cooling plate configurations, serpentine and straight, were tested. Air, water, and oil were used as coolants. Measurements for the heat transfer coefficient and the thermal contact resistance were made for various flow rates ranging from 16 to 88 Kg/hr, and stack clamping pressure ranging from O to 3448 Kpa. The experimental results for the overall heat transfer coefficient were utilized to derive mathematical relations for the overall heat transfer coefficient as a function of stack clamping pressure and Reynolds number for the three coolants. The empirically derived formulas were incorporated in a previously developed computer program to predict electrodes temperature distribution and the performance of the stack cooling system. The results obtained were then compared with those available in the literature. The comparison showed maximum deviation of +/- 11%.

Testing of an Ammonia EVA Vent Tool for the International Space Station

NASA Technical Reports Server (NTRS)

Ungar, Eugene K.; Stanewich, Brett J.; Wilhelm, Sheri Munekata

2000-01-01

When components of the International Space Station ammonia External Active Thermal Control System are replaced on-orbit, they must be vented immediately after removal from the system. Venting ensures that the component is not hard packed with liquid and thus does not pose a hazard. An extravehicular activity (EVA) vent tool has been developed to perform this function. However, there were concerns that the tool could whip, posing a hazard to the EVA astronaut, or would freeze. The ammonia vent tool was recently tested in a thermal/vacuum chamber to demonstrate that it would operate safely and would not freeze during venting. During the test, ammonia mimicking the venting conditions for six different heat exchanger initial conditions was passed through representative test articles. In the present work, the model that was used to develop the ammonia state and flow for the test points is discussed and the test setup and operation is described. The qualitative whipping and freezing results of the test are discussed and vent plume pressure measurements are described and interpreted.

Modeling and analysis of chill and fill processes for the cryogenic storage and transfer engineering development unit tank

NASA Astrophysics Data System (ADS)

Hedayat, A.; Cartagena, W.; Majumdar, A. K.; LeClair, A. C.

2016-03-01

NASA's future missions may require long-term storage and transfer of cryogenic propellants. The Engineering Development Unit (EDU), a NASA in-house effort supported by both Marshall Space Flight Center (MSFC) and Glenn Research Center, is a cryogenic fluid management (CFM) test article that primarily serves as a manufacturing pathfinder and a risk reduction task for a future CFM payload. The EDU test article comprises a flight-like tank, internal components, insulation, and attachment struts. The EDU is designed to perform integrated passive thermal control performance testing with liquid hydrogen (LH2) in a test-like vacuum environment. A series of tests, with LH2 as a testing fluid, was conducted at Test Stand 300 at MSFC during the summer of 2014. The objective of this effort was to develop a thermal/fluid model for evaluating the thermodynamic behavior of the EDU tank during the chill and fill processes. The Generalized Fluid System Simulation Program, an MSFC in-house general-purpose computer program for flow network analysis, was utilized to model and simulate the chill and fill portion of the testing. The model contained the LH2 supply source, feed system, EDU tank, and vent system. The test setup, modeling description, and comparison of model predictions with the test data are presented.

Detection of geometric phases in superconducting nanocircuits

PubMed

Falci; Fazio; Palma; Siewert; Vedral

2000-09-21

When a quantum-mechanical system undergoes an adiabatic cyclic evolution, it acquires a geometrical phase factor' in addition to the dynamical one; this effect has been demonstrated in a variety of microscopic systems. Advances in nanotechnology should enable the laws of quantum dynamics to be tested at the macroscopic level, by providing controllable artificial two-level systems (for example, in quantum dots and superconducting devices). Here we propose an experimental method to detect geometric phases in a superconducting device. The setup is a Josephson junction nanocircuit consisting of a superconducting electron box. We discuss how interferometry based on geometrical phases may be realized, and show how the effect may be applied to the design of gates for quantum computation.

A far-field radio-frequency experimental exposure system with unrestrained mice.

PubMed

Hansen, Jared W; Asif, Sajid; Singelmann, Lauren; Khan, Muhammad Saeed; Ghosh, Sumit; Gustad, Tom; Doetkott, Curt; Braaten, Benjamin D; Ewert, Daniel L

2015-01-01

Many studies have been performed on exploring the effects of radio-frequency (RF) energy on biological function in vivo. In particular, gene expression results have been inconclusive due, in part, to a lack of a standardized experimental procedure. This research describes a new far field RF exposure system for unrestrained murine models that reduces experimental error. The experimental procedure includes the materials used, the creation of a patch antenna, the uncertainty analysis of the equipment, characterization of the test room, experimental equipment used and setup, power density and specific absorption rate experiment, and discussion. The result of this research is an experimental exposure system to be applied to future biological studies.

A multiprojection noncontact fluorescence tomography setup for imaging arbitrary geometries

NASA Astrophysics Data System (ADS)

Meyer, H.; Garofalakis, A.; Zacharakis, G.; Economou, E. N.; Mamalaki, C.; Kioussis, D.; Ntziachristos, V.; Ripoll, J.

2005-04-01

Optical imaging and tomography in tissues can facilitate the quantitative study of several important chromophores and fluorophores in-vivo. Due to this fact, there has been great interest in developing imaging systems offering quantitative information on the location and concentration of chromophores and fluorescent probes. However, most imaging systems currently used in research make use of fiber technology for delivery and detection, which restricts the size of the photon collecting arrays leading to insufficient spatial sampling and field of view. To enable large data sets and full 360o angular measurements, we developed a novel imaging system that enables 3D imaging of fluorescent signals in bodies of arbitrary shapes in a non-contact geometry in combination with a 3D surface reconstruction algorithm. The system consists of a rotating subject holder and a lens coupled Charge Coupled Device (CCD) camera in combination with a fiber coupled laser scanning device. An Argon ion laser is used as the source and different filters are used for the detection of various fluorophores or fluorescing proteins. With this new setup a large measurements dataset can be achieved while the use of inversion models give a high capacity for quantitative 3D reconstruction of fluorochrome distributions as well as high spatial resolution. The system is currently being tested in the observation of the distribution of Green Fluorescent Protein (GFP) expressing T-lymphocytes in order to study the function of the immune system in a murine model.

A novel dynamic mechanical testing technique for reverse shoulder replacements.

PubMed

Dabirrahmani, Danè; Bokor, Desmond; Appleyard, Richard

2014-04-01

In vitro mechanical testing of orthopedic implants provides information regarding their mechanical performance under simulated biomechanical conditions. Current in vitro component stability testing methods for reverse shoulder implants are based on anatomical shoulder designs, which do not capture the dynamic nature of these loads. With glenoid component loosening as one of the most prevalent modes of failure in reverse shoulder replacements, it is important to establish a testing protocol with a more realistic loading regime. This paper introduces a novel method of mechanically testing reverse shoulder implants, using more realistic load magnitudes and vectors, than is currently practiced. Using a custom made jig setup within an Instron mechanical testing system, it is possible to simulate the change in magnitude and direction of the joint load during arm abduction. This method is a step towards a more realistic testing protocol for measuring reverse shoulder implant stability.

A multiparallel bioreactor for the cultivation of mammalian cells in a 3D-ceramic matrix.

PubMed

Goralczyk, Vicky; Driemel, Gregor; Bischof, Andreas; Peter, Andrea; Berthold, Almuth; Kroh, Lothar; Blessing, Lucienne; Schubert, Helmut; King, Rudibert

2010-01-01

For adherently growing cells, cultivation is limited by the provided growth surface. Excellent surface-to-volume ratios are found in highly porous matrices, which have to face the challenge of nutrient supply inside the matrices' caverns. Therefore, perfusion strategies are recommended which often have to deal with the need of developing an encompassing bioreactor periphery. We present a modular bioreactor system based on a porous ceramic matrix that enables the supply of cells with oxygen and nutrients by perfusion. The present version of the reactor system focuses on simple testing of various inoculation and operation modes. Moreover, it can be used to efficiently test different foam structures. Protocols are given to set-up the system together with handling procedures for long-time cultivation of a CHO cell line. Experimental results confirm vital growth of cells inside the matrices' caverns.

A concept to transfer a therapeutic splint position into permanent occlusion with a customized lingual appliance.

PubMed

Sachse, Tina; Schwestka-Polly, Rainer; Flieger, Stefanie; Wiechmann, Dirk

2012-05-21

The role of occlusion concerning temporomandibular disorder is still unclear but seems to be the only component of the stomathognathic system dentists are able to change morphologically. The aim of the paper is to describe the orthodontist's approach for transferring and maintaining a therapeutic splint position into permanent occlusion using a fully customized lingual appliance. Fixed acrylic bite planes on lower molars were used to maintain a symptom-free condyle position prior to orthodontic treatment. Silicone impressions of the arches including the fixed bite planes were used for the Incognito laboratory procedure. Two digital setups were made. One setup represents the target occlusion. A second setup including the bite planes was used to fabricate an additional set of lower molar brackets. In the leveling stage all teeth except the lower molars were settled to maintain the therapeutic condyle position. Finally, the fixed bite planes were stepwise removed and molar brackets were replaced to establish the permanent occlusion planned with the first setup. The advantage of an individual lingual appliance consists in the high level of congruence between the fabricated setups and the final clinical result. Both the individual scope for design and the precision of the appliance were vitally important in the treatment of a patient with a functional disorder of the masticatory system.

Needleless electrospinning with twisted wire spinneret

NASA Astrophysics Data System (ADS)

Holopainen, Jani; Penttinen, Toni; Santala, Eero; Ritala, Mikko

2015-01-01

A needleless electrospinning setup named ‘Needleless Twisted Wire Electrospinning’ was developed. The polymer solution is electrospun from the surface of a twisted wire set to a high voltage and collected on a cylindrical collector around the wire. Multiple Taylor cones are simultaneously self-formed on the downward flowing solution. The system is robust and simple with no moving parts aside from the syringe pump used to transport the solution to the top of the wire. The structure and process parameters of the setup and the results on the preparation of polyvinyl pyrrolidone (PVP), hydroxyapatite (HA) and bioglass fibers with the setup are presented. PVP fiber sheets with areas of 40 × 120 cm2 and masses up to 1.15 g were prepared. High production rates of 5.23 g h-1 and 1.40 g h-1 were achieved for PVP and HA respectively. The major limiting factor of the setup is drying of the polymer solution on the wire during the electrospinning process which will eventually force to interrupt the process for cleaning of the wire. Possible solutions to this problem and other ways to develop the setup are discussed. The presented system provides a simple way to increase the production rate and area of fiber sheet as compared with the conventional needle electrospinning.

Real-time real-sky dual-conjugate adaptive optics experiment

NASA Astrophysics Data System (ADS)

Knutsson, Per; Owner-Petersen, Mette

2006-06-01

The current status of a real-time real-sky dual-conjugate adaptive optics experiment is presented. This experiment is a follow-up on a lab experiment at Lund Observatory that demonstrated dual-conjugate adaptive optics on a static atmosphere. The setup is to be placed at Lund Observatory. This means that the setup will be available 24h a day and does not have to share time with other instruments. The optical design of the experiment is finalized. A siderostat will be used to track the guide object and all other optical components are placed on an optical table. A small telescope, 35 cm aperture, is used and following this a tip-tilt mirror and two deformable mirrors are placed. The wave-front sensor is a Shack-Hartmann sensor using a SciMeasure Li'l Joe CCD39 camera system. The maximum update rate of the setup will be 0.5 kHz and the control system will be running under Linux. The effective wavelength will be 750 nm. All components in the setup have been acquired and the completion of the setup is underway. Collaborating partners in this project are the Applied Optics Group at National University of Ireland, Galway and the Swedish Defense Research Agency.