WorldWideScience

Sample records for ground testbed experiment

  1. Passive Thermal Design Approach for the Space Communications and Navigation (SCaN) Testbed Experiment on the International Space Station (ISS)

    Science.gov (United States)

    Siamidis, John; Yuko, Jim

    2014-01-01

    The Space Communications and Navigation (SCaN) Program Office at NASA Headquarters oversees all of NASAs space communications activities. SCaN manages and directs the ground-based facilities and services provided by the Deep Space Network (DSN), Near Earth Network (NEN), and the Space Network (SN). Through the SCaN Program Office, NASA GRC developed a Software Defined Radio (SDR) testbed experiment (SCaN testbed experiment) for use on the International Space Station (ISS). It is comprised of three different SDR radios, the Jet Propulsion Laboratory (JPL) radio, Harris Corporation radio, and the General Dynamics Corporation radio. The SCaN testbed experiment provides an on-orbit, adaptable, SDR Space Telecommunications Radio System (STRS) - based facility to conduct a suite of experiments to advance the Software Defined Radio, Space Telecommunications Radio Systems (STRS) standards, reduce risk (Technology Readiness Level (TRL) advancement) for candidate Constellation future space flight hardware software, and demonstrate space communication links critical to future NASA exploration missions. The SCaN testbed project provides NASA, industry, other Government agencies, and academic partners the opportunity to develop and field communications, navigation, and networking technologies in the laboratory and space environment based on reconfigurable, software defined radio platforms and the STRS Architecture.The SCaN testbed is resident on the P3 Express Logistics Carrier (ELC) on the exterior truss of the International Space Station (ISS). The SCaN testbed payload launched on the Japanese Aerospace Exploration Agency (JAXA) H-II Transfer Vehicle (HTV) and was installed on the ISS P3 ELC located on the inboard RAM P3 site. The daily operations and testing are managed out of NASA GRC in the Telescience Support Center (TSC).

  2. Design of aircraft cabin testbed for stress free air travel experiment

    NARCIS (Netherlands)

    Tan, C.F.; Chen, W.; Rauterberg, G.W.M.

    2009-01-01

    The paper presents an aircraft cabin testbed that is designed and built for the stress free air travel experiment. The project is funded by European Union in the aim of improving air travel comfort during long haul flight. The testbed is used to test and validate the adaptive system that is capable

  3. Mini-mast CSI testbed user's guide

    Science.gov (United States)

    Tanner, Sharon E.; Pappa, Richard S.; Sulla, Jeffrey L.; Elliott, Kenny B.; Miserentino, Robert; Bailey, James P.; Cooper, Paul A.; Williams, Boyd L., Jr.; Bruner, Anne M.

    1992-01-01

    The Mini-Mast testbed is a 20 m generic truss highly representative of future deployable trusses for space applications. It is fully instrumented for system identification and active vibrations control experiments and is used as a ground testbed at NASA-Langley. The facility has actuators and feedback sensors linked via fiber optic cables to the Advanced Real Time Simulation (ARTS) system, where user defined control laws are incorporated into generic controls software. The object of the facility is to conduct comprehensive active vibration control experiments on a dynamically realistic large space structure. A primary goal is to understand the practical effects of simplifying theoretical assumptions. This User's Guide describes the hardware and its primary components, the dynamic characteristics of the test article, the control law implementation process, and the necessary safeguards employed to protect the test article. Suggestions for a strawman controls experiment are also included.

  4. NASA Langley's AirSTAR Testbed: A Subscale Flight Test Capability for Flight Dynamics and Control System Experiments

    Science.gov (United States)

    Jordan, Thomas L.; Bailey, Roger M.

    2008-01-01

    As part of the Airborne Subscale Transport Aircraft Research (AirSTAR) project, NASA Langley Research Center (LaRC) has developed a subscaled flying testbed in order to conduct research experiments in support of the goals of NASA s Aviation Safety Program. This research capability consists of three distinct components. The first of these is the research aircraft, of which there are several in the AirSTAR stable. These aircraft range from a dynamically-scaled, twin turbine vehicle to a propeller driven, off-the-shelf airframe. Each of these airframes carves out its own niche in the research test program. All of the airplanes have sophisticated on-board data acquisition and actuation systems, recording, telemetering, processing, and/or receiving data from research control systems. The second piece of the testbed is the ground facilities, which encompass the hardware and software infrastructure necessary to provide comprehensive support services for conducting flight research using the subscale aircraft, including: subsystem development, integrated testing, remote piloting of the subscale aircraft, telemetry processing, experimental flight control law implementation and evaluation, flight simulation, data recording/archiving, and communications. The ground facilities are comprised of two major components: (1) The Base Research Station (BRS), a LaRC laboratory facility for system development, testing and data analysis, and (2) The Mobile Operations Station (MOS), a self-contained, motorized vehicle serving as a mobile research command/operations center, functionally equivalent to the BRS, capable of deployment to remote sites for supporting flight tests. The third piece of the testbed is the test facility itself. Research flights carried out by the AirSTAR team are conducted at NASA Wallops Flight Facility (WFF) on the Eastern Shore of Virginia. The UAV Island runway is a 50 x 1500 paved runway that lies within restricted airspace at Wallops Flight Facility. The

  5. COLUMBUS as Engineering Testbed for Communications and Multimedia Equipment

    Science.gov (United States)

    Bank, C.; Anspach von Broecker, G. O.; Kolloge, H.-G.; Richters, M.; Rauer, D.; Urban, G.; Canovai, G.; Oesterle, E.

    2002-01-01

    The paper presents ongoing activities to prepare COLUMBUS for communications and multimedia technology experiments. For this purpose, Astrium SI, Bremen, has studied several options how to best combine the given system architecture with flexible and state-of-the-art interface avionics and software. These activities have been conducted in coordination with, and partially under contract of, DLR and ESA/ESTEC. Moreover, Astrium SI has realized three testbeds for multimedia software and hardware testing under own funding. The experimental core avionics unit - about a half double rack - establishes the core of a new multi-user experiment facility for this type of investigation onboard COLUMBUS, which shall be available to all users of COLUMBUS. It allows for the connection of 2nd generation payload, that is payload requiring broadband data transfer and near-real-time access by the Principal Investigator on ground, to test highly interactive and near-realtime payload operation. The facility is also foreseen to test new equipment to provide the astronauts onboard the ISS/COLUMBUS with bi- directional hi-fi voice and video connectivity to ground, private voice coms and e-mail, and a multimedia workstation for ops training and recreation. Connection to an appropriate Wide Area Network (WAN) on Earth is possible. The facility will include a broadband data transmission front-end terminal, which is mounted externally on the COLUMBUS module. This Equipment provides high flexibility due to the complete transparent transmit and receive chains, the steerable multi-frequency antenna system and its own thermal and power control and distribution. The Equipment is monitored and controlled via the COLUMBUS internal facility. It combines several new hardware items, which are newly developed for the next generation of broadband communication satellites and operates in Ka -Band with the experimental ESA data relay satellite ARTEMIS. The equipment is also TDRSS compatible; the open loop

  6. Thermal and Fluid Modeling of the CRYogenic Orbital TEstbed (CRYOTE) Ground Test Article (GTA)

    Science.gov (United States)

    Piryk, David; Schallhorn, Paul; Walls, Laurie; Stopnitzky, Benny; Rhys, Noah; Wollen, Mark

    2012-01-01

    The purpose of this study was to anchor thermal and fluid system models to data acquired from a ground test article (GTA) for the CRYogenic Orbital TEstbed - CRYOTE. To accomplish this analysis, it was broken into four primary tasks. These included model development, pre-test predictions, testing support at Marshall Space Flight Center (MSFC} and post-test correlations. Information from MSFC facilitated the task of refining and correlating the initial models. The primary goal of the modeling/testing/correlating efforts was to characterize heat loads throughout the ground test article. Significant factors impacting the heat loads included radiative environments, multi-layer insulation (MLI) performance, tank fill levels, tank pressures, and even contact conductance coefficients. This paper demonstrates how analytical thermal/fluid networks were established, and it includes supporting rationale for specific thermal responses seen during testing.

  7. Variable Coding and Modulation Experiment Using NASA's Space Communication and Navigation Testbed

    Science.gov (United States)

    Downey, Joseph A.; Mortensen, Dale J.; Evans, Michael A.; Tollis, Nicholas S.

    2016-01-01

    National Aeronautics and Space Administration (NASA)'s Space Communication and Navigation Testbed on the International Space Station provides a unique opportunity to evaluate advanced communication techniques in an operational system. The experimental nature of the Testbed allows for rapid demonstrations while using flight hardware in a deployed system within NASA's networks. One example is variable coding and modulation, which is a method to increase data-throughput in a communication link. This paper describes recent flight testing with variable coding and modulation over S-band using a direct-to-earth link between the SCaN Testbed and the Glenn Research Center. The testing leverages the established Digital Video Broadcasting Second Generation (DVB-S2) standard to provide various modulation and coding options. The experiment was conducted in a challenging environment due to the multipath and shadowing caused by the International Space Station structure. Performance of the variable coding and modulation system is evaluated and compared to the capacity of the link, as well as standard NASA waveforms.

  8. A Reconfigurable Testbed Environment for Spacecraft Autonomy

    Science.gov (United States)

    Biesiadecki, Jeffrey; Jain, Abhinandan

    1996-01-01

    A key goal of NASA's New Millennium Program is the development of technology for increased spacecraft on-board autonomy. Achievement of this objective requires the development of a new class of ground-based automony testbeds that can enable the low-cost and rapid design, test, and integration of the spacecraft autonomy software. This paper describes the development of an Autonomy Testbed Environment (ATBE) for the NMP Deep Space I comet/asteroid rendezvous mission.

  9. Telescience testbed: Operational support functions for biomedical experiments

    Science.gov (United States)

    Yamashita, Masamichi; Watanabe, Satoru; Shoji, Takatoshi; Clarke, Andrew H.; Suzuki, Hiroyuki; Yanagihara, Dai

    A telescience testbed was conducted to study the methodology of space biomedicine with simulated constraints imposed on space experiments. An experimental subject selected for this testbedding was an elaborate surgery of animals and electrophysiological measurements conducted by an operator onboard. The standing potential in the ampulla of the pigeon's semicircular canal was measured during gravitational and caloric stimulation. A principal investigator, isolated from the operation site, participated in the experiment interactively by telecommunication links. Reliability analysis was applied to the whole layers of experimentation, including design of experimental objectives and operational procedures. Engineering and technological aspects of telescience are discussed in terms of reliability to assure quality of science. Feasibility of robotics was examined for supportive functions to reduce the workload of the onboard operator.

  10. Results from a multi aperture Fizeau interferometer ground testbed: demonstrator for a future space-based interferometer

    Science.gov (United States)

    Baccichet, Nicola; Caillat, Amandine; Rakotonimbahy, Eddy; Dohlen, Kjetil; Savini, Giorgio; Marcos, Michel

    2016-08-01

    In the framework of the European FP7-FISICA (Far Infrared Space Interferometer Critical Assessment) program, we developed a miniaturized version of the hyper-telescope to demonstrate multi-aperture interferometry on ground. This setup would be ultimately integrated into a CubeSat platform, therefore providing the first real demonstrator of a multi aperture Fizeau interferometer in space. In this paper, we describe the optical design of the ground testbed and the data processing pipeline implemented to reconstruct the object image from interferometric data. As a scientific application, we measured the Sun diameter by fitting a limb-darkening model to our data. Finally, we present the design of a CubeSat platform carrying this miniature Fizeau interferometer, which could be used to monitor the Sun diameter over a long in-orbit period.

  11. Trace explosives sensor testbed (TESTbed)

    Science.gov (United States)

    Collins, Greg E.; Malito, Michael P.; Tamanaha, Cy R.; Hammond, Mark H.; Giordano, Braden C.; Lubrano, Adam L.; Field, Christopher R.; Rogers, Duane A.; Jeffries, Russell A.; Colton, Richard J.; Rose-Pehrsson, Susan L.

    2017-03-01

    A novel vapor delivery testbed, referred to as the Trace Explosives Sensor Testbed, or TESTbed, is demonstrated that is amenable to both high- and low-volatility explosives vapors including nitromethane, nitroglycerine, ethylene glycol dinitrate, triacetone triperoxide, 2,4,6-trinitrotoluene, pentaerythritol tetranitrate, and hexahydro-1,3,5-trinitro-1,3,5-triazine. The TESTbed incorporates a six-port dual-line manifold system allowing for rapid actuation between a dedicated clean air source and a trace explosives vapor source. Explosives and explosives-related vapors can be sourced through a number of means including gas cylinders, permeation tube ovens, dynamic headspace chambers, and a Pneumatically Modulated Liquid Delivery System coupled to a perfluoroalkoxy total-consumption microflow nebulizer. Key features of the TESTbed include continuous and pulseless control of trace vapor concentrations with wide dynamic range of concentration generation, six sampling ports with reproducible vapor profile outputs, limited low-volatility explosives adsorption to the manifold surface, temperature and humidity control of the vapor stream, and a graphical user interface for system operation and testing protocol implementation.

  12. An adaptable, low cost test-bed for unmanned vehicle systems research

    Science.gov (United States)

    Goppert, James M.

    2011-12-01

    An unmanned vehicle systems test-bed has been developed. The test-bed has been designed to accommodate hardware changes and various vehicle types and algorithms. The creation of this test-bed allows research teams to focus on algorithm development and employ a common well-tested experimental framework. The ArduPilotOne autopilot was developed to provide the necessary level of abstraction for multiple vehicle types. The autopilot was also designed to be highly integrated with the Mavlink protocol for Micro Air Vehicle (MAV) communication. Mavlink is the native protocol for QGroundControl, a MAV ground control program. Features were added to QGroundControl to accommodate outdoor usage. Next, the Mavsim toolbox was developed for Scicoslab to allow hardware-in-the-loop testing, control design and analysis, and estimation algorithm testing and verification. In order to obtain linear models of aircraft dynamics, the JSBSim flight dynamics engine was extended to use a probabilistic Nelder-Mead simplex method. The JSBSim aircraft dynamics were compared with wind-tunnel data collected. Finally, a structured methodology for successive loop closure control design is proposed. This methodology is demonstrated along with the rest of the test-bed tools on a quadrotor, a fixed wing RC plane, and a ground vehicle. Test results for the ground vehicle are presented.

  13. The Living With a Star Space Environment Testbed Experiments

    Science.gov (United States)

    Xapsos, Michael A.

    2014-01-01

    The focus of the Living With a Star (LWS) Space Environment Testbed (SET) program is to improve the performance of hardware in the space radiation environment. The program has developed a payload for the Air Force Research Laboratory (AFRL) Demonstration and Science Experiments (DSX) spacecraft that is scheduled for launch in August 2015 on the SpaceX Falcon Heavy rocket. The primary structure of DSX is an Evolved Expendable Launch Vehicle (EELV) Secondary Payload Adapter (ESPA) ring. DSX will be in a Medium Earth Orbit (MEO). This oral presentation will describe the SET payload.

  14. Adaptive Coding and Modulation Experiment With NASA's Space Communication and Navigation Testbed

    Science.gov (United States)

    Downey, Joseph; Mortensen, Dale; Evans, Michael; Briones, Janette; Tollis, Nicholas

    2016-01-01

    National Aeronautics and Space Administration (NASA)'s Space Communication and Navigation Testbed is an advanced integrated communication payload on the International Space Station. This paper presents results from an adaptive coding and modulation (ACM) experiment over S-band using a direct-to-earth link between the SCaN Testbed and the Glenn Research Center. The testing leverages the established Digital Video Broadcasting Second Generation (DVB-S2) standard to provide various modulation and coding options, and uses the Space Data Link Protocol (Consultative Committee for Space Data Systems (CCSDS) standard) for the uplink and downlink data framing. The experiment was conducted in a challenging environment due to the multipath and shadowing caused by the International Space Station structure. Several approaches for improving the ACM system are presented, including predictive and learning techniques to accommodate signal fades. Performance of the system is evaluated as a function of end-to-end system latency (round-trip delay), and compared to the capacity of the link. Finally, improvements over standard NASA waveforms are presented.

  15. Nuclear Instrumentation and Control Cyber Testbed Considerations – Lessons Learned

    Energy Technology Data Exchange (ETDEWEB)

    Jonathan Gray; Robert Anderson; Julio G. Rodriguez; Cheol-Kwon Lee

    2014-08-01

    Abstract: Identifying and understanding digital instrumentation and control (I&C) cyber vulnerabilities within nuclear power plants and other nuclear facilities, is critical if nation states desire to operate nuclear facilities safely, reliably, and securely. In order to demonstrate objective evidence that cyber vulnerabilities have been adequately identified and mitigated, a testbed representing a facility’s critical nuclear equipment must be replicated. Idaho National Laboratory (INL) has built and operated similar testbeds for common critical infrastructure I&C for over ten years. This experience developing, operating, and maintaining an I&C testbed in support of research identifying cyber vulnerabilities has led the Korean Atomic Energy Research Institute of the Republic of Korea to solicit the experiences of INL to help mitigate problems early in the design, development, operation, and maintenance of a similar testbed. The following information will discuss I&C testbed lessons learned and the impact of these experiences to KAERI.

  16. Exploration Systems Health Management Facilities and Testbed Workshop

    Science.gov (United States)

    Wilson, Scott; Waterman, Robert; McCleskey, Carey

    2004-01-01

    Presentation Agenda : (1) Technology Maturation Pipeline (The Plan) (2) Cryogenic testbed (and other KSC Labs) (2a) Component / Subsystem technologies (3) Advanced Technology Development Center (ATDC) (3a) System / Vehic1e technologies (4) EL V Flight Experiments (Flight Testbeds).

  17. SCaN Testbed Software Development and Lessons Learned

    Science.gov (United States)

    Kacpura, Thomas J.; Varga, Denise M.

    2012-01-01

    National Aeronautics and Space Administration (NASA) has developed an on-orbit, adaptable, Software Defined Radio (SDR)Space Telecommunications Radio System (STRS)-based testbed facility to conduct a suite of experiments to advance technologies, reduce risk, and enable future mission capabilities on the International Space Station (ISS). The SCAN Testbed Project will provide NASA, industry, other Government agencies, and academic partners the opportunity to develop and field communications, navigation, and networking technologies in the laboratory and space environment based on reconfigurable, SDR platforms and the STRS Architecture.The SDRs are a new technology for NASA, and the support infrastructure they require is different from legacy, fixed function radios. SDRs offer the ability to reconfigure on-orbit communications by changing software for new waveforms and operating systems to enable new capabilities or fix any anomalies, which was not a previous option. They are not stand alone devices, but required a new approach to effectively control them and flow data. This requires extensive software to be developed to utilize the full potential of these reconfigurable platforms. The paper focuses on development, integration and testing as related to the avionics processor system, and the software required to command, control, monitor, and interact with the SDRs, as well as the other communication payload elements. An extensive effort was required to develop the flight software and meet the NASA requirements for software quality and safety. The flight avionics must be radiation tolerant, and these processors have limited capability in comparison to terrestrial counterparts. A big challenge was that there are three SDRs onboard, and interfacing with multiple SDRs simultaneously complicatesd the effort. The effort also includes ground software, which is a key element for both the command of the payload, and displaying data created by the payload. The verification of

  18. SCDU Testbed Automated In-Situ Alignment, Data Acquisition and Analysis

    Science.gov (United States)

    Werne, Thomas A.; Wehmeier, Udo J.; Wu, Janet P.; An, Xin; Goullioud, Renaud; Nemati, Bijan; Shao, Michael; Shen, Tsae-Pyng J.; Wang, Xu; Weilert, Mark A.; hide

    2010-01-01

    In the course of fulfilling its mandate, the Spectral Calibration Development Unit (SCDU) testbed for SIM-Lite produces copious amounts of raw data. To effectively spend time attempting to understand the science driving the data, the team devised computerized automations to limit the time spent bringing the testbed to a healthy state and commanding it, and instead focus on analyzing the processed results. We developed a multi-layered scripting language that emphasized the scientific experiments we conducted, which drastically shortened our experiment scripts, improved their readability, and all-but-eliminated testbed operator errors. In addition to scientific experiment functions, we also developed a set of automated alignments that bring the testbed up to a well-aligned state with little more than the push of a button. These scripts were written in the scripting language, and in Matlab via an interface library, allowing all members of the team to augment the existing scripting language with complex analysis scripts. To keep track of these results, we created an easily-parseable state log in which we logged both the state of the testbed and relevant metadata. Finally, we designed a distributed processing system that allowed us to farm lengthy analyses to a collection of client computers which reported their results in a central log. Since these logs were parseable, we wrote query scripts that gave us an effortless way to compare results collected under different conditions. This paper serves as a case-study, detailing the motivating requirements for the decisions we made and explaining the implementation process.

  19. Use of Bioregenerative Technologies for Advanced Life Support: Some Considerations for BIO-Plex and Related Testbeds

    Science.gov (United States)

    Wheeler, Raymond M.; Strayer, Richard F.

    1997-01-01

    A review of bioregenerative life support concepts is provided as a guide for developing ground-based testbeds for NASA's Advanced Life Support Program. Key among these concepts are the use of controlled environment plant culture for the production of food, oxygen, and clean water, and the use of bacterial bioreactors for degrading wastes and recycling nutrients. Candidate crops and specific bioreactor approaches are discussed based on experiences from the. Kennedy Space Center Advanced Life Support Breadboard Project, and a review of related literature is provided.

  20. Diffraction-based analysis of tunnel size for a scaled external occulter testbed

    Science.gov (United States)

    Sirbu, Dan; Kasdin, N. Jeremy; Vanderbei, Robert J.

    2016-07-01

    For performance verification of an external occulter mask (also called a starshade), scaled testbeds have been developed to measure the suppression of the occulter shadow in the pupil plane and contrast in the image plane. For occulter experiments the scaling is typically performed by maintaining an equivalent Fresnel number. The original Princeton occulter testbed was oversized with respect to both input beam and shadow propagation to limit any diffraction effects due to finite testbed enclosure edges; however, to operate at realistic space-mission equivalent Fresnel numbers an extended testbed is currently under construction. With the longer propagation distances involved, diffraction effects due to the edge of the tunnel must now be considered in the experiment design. Here, we present a diffraction-based model of two separate tunnel effects. First, we consider the effect of tunnel-edge induced diffraction ringing upstream from the occulter mask. Second, we consider the diffraction effect due to clipping of the output shadow by the tunnel downstream from the occulter mask. These calculations are performed for a representative point design relevant to the new Princeton occulter experiment, but we also present an analytical relation that can be used for other propagation distances.

  1. The DataTAG transatlantic testbed

    CERN Document Server

    Martin, O; Martin-Flatin, J P; Moroni, P; Nae, D; Newman, H; Ravot, S

    2005-01-01

    Wide area network testbeds allow researchers and engineers to test out new equipment, protocols and services in real-life situations, without jeopardizing the stability and reliability of production networks. The Data TransAtlantic Grid (DataTAG) testbed, deployed in 2002 between CERN, Geneva, Switzerland and StarLight, Chicago, IL, USA, is probably the largest testbed built to date. Jointly managed by CERN and Caltech, it is funded by the European Commission, the U.S. Department of Energy and the U.S. National Science Foundation. The main objectives of this testbed are to improve the Grid community's understanding of the networking issues posed by data- intensive Grid applications over transoceanic gigabit networks, design and develop new Grid middleware services, and improve the interoperability of European and U.S. Grid applications in High- Energy and Nuclear Physics. In this paper, we give an overview of this testbed, describe its various topologies over time, and summarize the main lessons learned after...

  2. INFN Tier-1 Testbed Facility

    International Nuclear Information System (INIS)

    Gregori, Daniele; Cavalli, Alessandro; Dell'Agnello, Luca; Dal Pra, Stefano; Prosperini, Andrea; Ricci, Pierpaolo; Ronchieri, Elisabetta; Sapunenko, Vladimir

    2012-01-01

    INFN-CNAF, located in Bologna, is the Information Technology Center of National Institute of Nuclear Physics (INFN). In the framework of the Worldwide LHC Computing Grid, INFN-CNAF is one of the eleven worldwide Tier-1 centers to store and reprocessing Large Hadron Collider (LHC) data. The Italian Tier-1 provides the resources of storage (i.e., disk space for short term needs and tapes for long term needs) and computing power that are needed for data processing and analysis to the LHC scientific community. Furthermore, INFN Tier-1 houses computing resources for other particle physics experiments, like CDF at Fermilab, SuperB at Frascati, as well as for astro particle and spatial physics experiments. The computing center is a very complex infrastructure, the hardaware layer include the network, storage and farming area, while the software layer includes open source and proprietary software. Software updating and new hardware adding can unexpectedly deteriorate the production activity of the center: therefore a testbed facility has been set up in order to reproduce and certify the various layers of the Tier-1. In this article we describe the testbed and the checks performed.

  3. Ames life science telescience testbed evaluation

    Science.gov (United States)

    Haines, Richard F.; Johnson, Vicki; Vogelsong, Kristofer H.; Froloff, Walt

    1989-01-01

    Eight surrogate spaceflight mission specialists participated in a real-time evaluation of remote coaching using the Ames Life Science Telescience Testbed facility. This facility consisted of three remotely located nodes: (1) a prototype Space Station glovebox; (2) a ground control station; and (3) a principal investigator's (PI) work area. The major objective of this project was to evaluate the effectiveness of telescience techniques and hardware to support three realistic remote coaching science procedures: plant seed germinator charging, plant sample acquisition and preservation, and remote plant observation with ground coaching. Each scenario was performed by a subject acting as flight mission specialist, interacting with a payload operations manager and a principal investigator expert. All three groups were physically isolated from each other yet linked by duplex audio and color video communication channels and networked computer workstations. Workload ratings were made by the flight and ground crewpersons immediately after completing their assigned tasks. Time to complete each scientific procedural step was recorded automatically. Two expert observers also made performance ratings and various error assessments. The results are presented and discussed.

  4. Current Developments in DETER Cybersecurity Testbed Technology

    Science.gov (United States)

    2015-12-08

    Management Experimental cybersecurity research is often inherently risky. An experiment may involve releasing live malware code, operating a real botnet...imagine a worm that can only propagate by first contacting a “propagation service” (T1 constraint), composed with a testbed firewall (T2...experiment. Finally, T1 constraints might be enforced by (1) explicit modification of malware to constrain its behavior, (2) implicit constraints

  5. Development of a Testbed for Wireless Underground Sensor Networks

    Directory of Open Access Journals (Sweden)

    Mehmet C. Vuran

    2010-01-01

    Full Text Available Wireless Underground Sensor Networks (WUSNs constitute one of the promising application areas of the recently developed wireless sensor networking techniques. WUSN is a specialized kind of Wireless Sensor Network (WSN that mainly focuses on the use of sensors that communicate through soil. Recent models for the wireless underground communication channel are proposed but few field experiments were realized to verify the accuracy of the models. The realization of field WUSN experiments proved to be extremely complex and time-consuming in comparison with the traditional wireless environment. To the best of our knowledge, this is the first work that proposes guidelines for the development of an outdoor WUSN testbed with the goals of improving the accuracy and reducing of time for WUSN experiments. Although the work mainly aims WUSNs, many of the presented practices can also be applied to generic WSN testbeds.

  6. Mounted Smartphones as Measurement and Control Platforms for Motor-Based Laboratory Test-Beds

    Directory of Open Access Journals (Sweden)

    Jared A. Frank

    2016-08-01

    Full Text Available Laboratory education in science and engineering often entails the use of test-beds equipped with costly peripherals for sensing, acquisition, storage, processing, and control of physical behavior. However, costly peripherals are no longer necessary to obtain precise measurements and achieve stable feedback control of test-beds. With smartphones performing diverse sensing and processing tasks, this study examines the feasibility of mounting smartphones directly to test-beds to exploit their embedded hardware and software in the measurement and control of the test-beds. This approach is a first step towards replacing laboratory-grade peripherals with more compact and affordable smartphone-based platforms, whose interactive user interfaces can engender wider participation and engagement from learners. Demonstrative cases are presented in which the sensing, computation, control, and user interaction with three motor-based test-beds are handled by a mounted smartphone. Results of experiments and simulations are used to validate the feasibility of mounted smartphones as measurement and feedback control platforms for motor-based laboratory test-beds, report the measurement precision and closed-loop performance achieved with such platforms, and address challenges in the development of platforms to maintain system stability.

  7. Mounted Smartphones as Measurement and Control Platforms for Motor-Based Laboratory Test-Beds.

    Science.gov (United States)

    Frank, Jared A; Brill, Anthony; Kapila, Vikram

    2016-08-20

    Laboratory education in science and engineering often entails the use of test-beds equipped with costly peripherals for sensing, acquisition, storage, processing, and control of physical behavior. However, costly peripherals are no longer necessary to obtain precise measurements and achieve stable feedback control of test-beds. With smartphones performing diverse sensing and processing tasks, this study examines the feasibility of mounting smartphones directly to test-beds to exploit their embedded hardware and software in the measurement and control of the test-beds. This approach is a first step towards replacing laboratory-grade peripherals with more compact and affordable smartphone-based platforms, whose interactive user interfaces can engender wider participation and engagement from learners. Demonstrative cases are presented in which the sensing, computation, control, and user interaction with three motor-based test-beds are handled by a mounted smartphone. Results of experiments and simulations are used to validate the feasibility of mounted smartphones as measurement and feedback control platforms for motor-based laboratory test-beds, report the measurement precision and closed-loop performance achieved with such platforms, and address challenges in the development of platforms to maintain system stability.

  8. Fast Physics Testbed for the FASTER Project

    Energy Technology Data Exchange (ETDEWEB)

    Lin, W.; Liu, Y.; Hogan, R.; Neggers, R.; Jensen, M.; Fridlind, A.; Lin, Y.; Wolf, A.

    2010-03-15

    This poster describes the Fast Physics Testbed for the new FAst-physics System Testbed and Research (FASTER) project. The overall objective is to provide a convenient and comprehensive platform for fast turn-around model evaluation against ARM observations and to facilitate development of parameterizations for cloud-related fast processes represented in global climate models. The testbed features three major components: a single column model (SCM) testbed, an NWP-Testbed, and high-resolution modeling (HRM). The web-based SCM-Testbed features multiple SCMs from major climate modeling centers and aims to maximize the potential of SCM approach to enhance and accelerate the evaluation and improvement of fast physics parameterizations through continuous evaluation of existing and evolving models against historical as well as new/improved ARM and other complementary measurements. The NWP-Testbed aims to capitalize on the large pool of operational numerical weather prediction products. Continuous evaluations of NWP forecasts against observations at ARM sites are carried out to systematically identify the biases and skills of physical parameterizations under all weather conditions. The highresolution modeling (HRM) activities aim to simulate the fast processes at high resolution to aid in the understanding of the fast processes and their parameterizations. A four-tier HRM framework is established to augment the SCM- and NWP-Testbeds towards eventual improvement of the parameterizations.

  9. Link Adaptation for Mitigating Earth-To-Space Propagation Effects on the NASA SCaN Testbed

    Science.gov (United States)

    Kilcoyne, Deirdre K.; Headley, William C.; Leffke, Zach J.; Rowe, Sonya A.; Mortensen, Dale J.; Reinhart, Richard C.; McGwier, Robert W.

    2016-01-01

    In Earth-to-Space communications, well-known propagation effects such as path loss and atmospheric loss can lead to fluctuations in the strength of the communications link between a satellite and its ground station. Additionally, the typically unconsidered effect of shadowing due to the geometry of the satellite and its solar panels can also lead to link degradation. As a result of these anticipated channel impairments, NASA's communication links have been traditionally designed to handle the worst-case impact of these effects through high link margins and static, lower rate, modulation formats. The work presented in this paper aims to relax these constraints by providing an improved trade-off between data rate and link margin through utilizing link adaptation. More specifically, this work provides a simulation study on the propagation effects impacting NASA's SCaN Testbed flight software-defined radio (SDR) as well as proposes a link adaptation algorithm that varies the modulation format of a communications link as its signal-to-noise ratio fluctuates. Ultimately, the models developed in this work will be utilized to conduct real-time flight experiments on-board the NASA SCaN Testbed.

  10. The Living With a Star Space Environment Testbed Payload

    Science.gov (United States)

    Xapsos, Mike

    2015-01-01

    This presentation outlines a brief description of the Living With a Star (LWS) Program missions and detailed information about the Space Environment Testbed (SET) payload consisting of a space weather monitor and carrier containing 4 board experiments.

  11. A remote integrated testbed for cooperating objects

    CERN Document Server

    Dios, Jose Ramiro Martinez-de; Bernabe, Alberto de San; Ollero, Anibal

    2013-01-01

    Testbeds are gaining increasing relevance in research domains and also in industrial applications. However, very few books devoted to testbeds have been published. To the best of my knowledge no book on this topic has been published. This book is particularly interesting for the growing community of testbed developers. I believe the book is also very interesting for researchers in robot-WSN cooperation.This book provides detailed description of a system that can be considered the first testbed that allows full peer-to-peer interoperability between heterogeneous robots and ubiquitous systems su

  12. Data Distribution Service-Based Interoperability Framework for Smart Grid Testbed Infrastructure

    Directory of Open Access Journals (Sweden)

    Tarek A. Youssef

    2016-03-01

    Full Text Available This paper presents the design and implementation of a communication and control infrastructure for smart grid operation. The proposed infrastructure enhances the reliability of the measurements and control network. The advantages of utilizing the data-centric over message-centric communication approach are discussed in the context of smart grid applications. The data distribution service (DDS is used to implement a data-centric common data bus for the smart grid. This common data bus improves the communication reliability, enabling distributed control and smart load management. These enhancements are achieved by avoiding a single point of failure while enabling peer-to-peer communication and an automatic discovery feature for dynamic participating nodes. The infrastructure and ideas presented in this paper were implemented and tested on the smart grid testbed. A toolbox and application programing interface for the testbed infrastructure are developed in order to facilitate interoperability and remote access to the testbed. This interface allows control, monitoring, and performing of experiments remotely. Furthermore, it could be used to integrate multidisciplinary testbeds to study complex cyber-physical systems (CPS.

  13. A Business-to-Business Interoperability Testbed: An Overview

    Energy Technology Data Exchange (ETDEWEB)

    Kulvatunyou, Boonserm [ORNL; Ivezic, Nenad [ORNL; Monica, Martin [Sun Microsystems, Inc.; Jones, Albert [National Institute of Standards and Technology (NIST)

    2003-10-01

    In this paper, we describe a business-to-business (B2B) testbed co-sponsored by the Open Applications Group, Inc. (OAGI) and the National Institute of Standard and Technology (NIST) to advance enterprise e-commerce standards. We describe the business and technical objectives and initial activities within the B2B Testbed. We summarize our initial lessons learned to form the requirements that drive the next generation testbed development. We also give an overview of a promising testing framework architecture in which to drive the testbed developments. We outline the future plans for the testbed development.

  14. Mounted Smartphones as Measurement and Control Platforms for Motor-Based Laboratory Test-Beds

    Science.gov (United States)

    Frank, Jared A.; Brill, Anthony; Kapila, Vikram

    2016-01-01

    Laboratory education in science and engineering often entails the use of test-beds equipped with costly peripherals for sensing, acquisition, storage, processing, and control of physical behavior. However, costly peripherals are no longer necessary to obtain precise measurements and achieve stable feedback control of test-beds. With smartphones performing diverse sensing and processing tasks, this study examines the feasibility of mounting smartphones directly to test-beds to exploit their embedded hardware and software in the measurement and control of the test-beds. This approach is a first step towards replacing laboratory-grade peripherals with more compact and affordable smartphone-based platforms, whose interactive user interfaces can engender wider participation and engagement from learners. Demonstrative cases are presented in which the sensing, computation, control, and user interaction with three motor-based test-beds are handled by a mounted smartphone. Results of experiments and simulations are used to validate the feasibility of mounted smartphones as measurement and feedback control platforms for motor-based laboratory test-beds, report the measurement precision and closed-loop performance achieved with such platforms, and address challenges in the development of platforms to maintain system stability. PMID:27556464

  15. An Overview of NASA's Subsonic Research Aircraft Testbed (SCRAT)

    Science.gov (United States)

    Baumann, Ethan; Hernandez, Joe; Ruhf, John C.

    2013-01-01

    National Aeronautics and Space Administration Dryden Flight Research Center acquired a Gulfstream III (GIII) aircraft to serve as a testbed for aeronautics flight research experiments. The aircraft is referred to as SCRAT, which stands for SubsoniC Research Aircraft Testbed. The aircraft's mission is to perform aeronautics research; more specifically raising the Technology Readiness Level (TRL) of advanced technologies through flight demonstrations and gathering high-quality research data suitable for verifying the technologies, and validating design and analysis tools. The SCRAT has the ability to conduct a range of flight research experiments throughout a transport class aircraft's flight envelope. Experiments ranging from flight-testing of a new aircraft system or sensor to those requiring structural and aerodynamic modifications to the aircraft can be accomplished. The aircraft has been modified to include an instrumentation system and sensors necessary to conduct flight research experiments along with a telemetry capability. An instrumentation power distribution system was installed to accommodate the instrumentation system and future experiments. An engineering simulation of the SCRAT has been developed to aid in integrating research experiments. A series of baseline aircraft characterization flights has been flown that gathered flight data to aid in developing and integrating future research experiments. This paper describes the SCRAT's research systems and capabilities.

  16. Recent Successes and Future Plans for NASA's Space Communications and Navigation Testbed on the International Space Station

    Science.gov (United States)

    Reinhart, Richard C.; Sankovic, John M.; Johnson, Sandra K.; Lux, James P.; Chelmins, David T.

    2014-01-01

    Flexible and extensible space communications architectures and technology are essential to enable future space exploration and science activities. NASA has championed the development of the Space Telecommunications Radio System (STRS) software defined radio (SDR) standard and the application of SDR technology to reduce the costs and risks of using SDRs for space missions, and has developed an on-orbit testbed to validate these capabilities. The Space Communications and Navigation (SCaN) Testbed (previously known as the Communications, Navigation, and Networking reConfigurable Testbed (CoNNeCT)) is advancing SDR, on-board networking, and navigation technologies by conducting space experiments aboard the International Space Station. During its first year(s) on-orbit, the SCaN Testbed has achieved considerable accomplishments to better understand SDRs and their applications. The SDR platforms and software waveforms on each SDR have over 1500 hours of operation and are performing as designed. The Ka-band SDR on the SCaN Testbed is NASAs first space Ka-band transceiver and is NASA's first Ka-band mission using the Space Network. This has provided exciting opportunities to operate at Ka-band and assist with on-orbit tests of NASA newest Tracking and Data Relay Satellites (TDRS). During its first year, SCaN Testbed completed its first on-orbit SDR reconfigurations. SDR reconfigurations occur when implementing new waveforms on an SDR. SDR reconfigurations allow a radio to change minor parameters, such as data rate, or complete functionality. New waveforms which provide new capability and are reusable across different missions provide long term value for reconfigurable platforms such as SDRs. The STRS Standard provides guidelines for new waveform development by third parties. Waveform development by organizations other than the platform provider offers NASA the ability to develop waveforms itself and reduce its dependence and costs on the platform developer. Each of these

  17. Data dissemination in the wild: A testbed for high-mobility MANETs

    DEFF Research Database (Denmark)

    Vingelmann, Peter; Pedersen, Morten Videbæk; Heide, Janus

    2012-01-01

    This paper investigates the problem of efficient data dissemination in Mobile Ad hoc NETworks (MANETs) with high mobility. A testbed is presented; which provides a high degree of mobility in experiments. The testbed consists of 10 autonomous robots with mobile phones mounted on them. The mobile...... information, and the goal is to convey that information to all devices. A strategy is proposed that uses UDP broadcast transmissions and random linear network coding to facilitate the efficient exchange of information in the network. An application is introduced that implements this strategy on Nokia phones...

  18. First light of an external occulter testbed at flight Fresnel numbers

    Science.gov (United States)

    Kim, Yunjong; Sirbu, Dan; Hu, Mia; Kasdin, Jeremy; Vanderbei, Robert J.; Harness, Anthony; Shaklan, Stuart

    2017-01-01

    Many approaches have been suggested over the last couple of decades for imaging Earth-like planets. One of the main candidates for creating high-contrast for future Earth-like planets detection is an external occulter. The external occulter is a spacecraft flown along the line-of-sight of a space telescope to suppress starlight and enable high-contrast direct imaging of exoplanets. The occulter is typically tens of meters in diameter and the separation from the telescope is of the order of tens of thousands of kilometers. Optical testing of a full-scale external occulter on the ground is impossible because of the long separations. Therefore, laboratory verification of occulter designs is necessary to validate the optical models used to design and predict occulter performance. At Princeton, we have designed and built a testbed that allows verification of scaled occulter designs whose suppressed shadow is mathematically identical to that of space occulters. The goal of this experiment is to demonstrate a pupil plane suppression of better than 1e-9 with a corresponding image plane contrast of better than 1e-11. The occulter testbed uses a 77.2 m optical propagation distance to realize the flight Fresnel number of 14.5. The scaled mask is placed at 27.2 m from the artificial source and the camera is located 50.0 m from the scaled mask. We will use an etched silicon mask, manufactured by the Microdevices Lab(MDL) of the Jet Propulsion Laboratory(JPL), as the occulter. Based on conversations with MDL, we expect that 0.5 μm feature size is an achievable resolution in the mask manufacturing process and is therefore likely the indicator of the best possible performance. The occulter is illuminated by a diverging laser beam to reduce the aberrations from the optics before the occulter. Here, we present first light result of a sample design operating at a flight Fresnel number and the experimental setup of the testbed. We compare the experimental results with simulations

  19. Automatic Integration Testbeds validation on Open Science Grid

    International Nuclear Information System (INIS)

    Caballero, J; Potekhin, M; Thapa, S; Gardner, R

    2011-01-01

    A recurring challenge in deploying high quality production middleware is the extent to which realistic testing occurs before release of the software into the production environment. We describe here an automated system for validating releases of the Open Science Grid software stack that leverages the (pilot-based) PanDA job management system developed and used by the ATLAS experiment. The system was motivated by a desire to subject the OSG Integration Testbed to more realistic validation tests. In particular those which resemble to every extent possible actual job workflows used by the experiments thus utilizing job scheduling at the compute element (CE), use of the worker node execution environment, transfer of data to/from the local storage element (SE), etc. The context is that candidate releases of OSG compute and storage elements can be tested by injecting large numbers of synthetic jobs varying in complexity and coverage of services tested. The native capabilities of the PanDA system can thus be used to define jobs, monitor their execution, and archive the resulting run statistics including success and failure modes. A repository of generic workflows and job types to measure various metrics of interest has been created. A command-line toolset has been developed so that testbed managers can quickly submit 'VO-like' jobs into the system when newly deployed services are ready for testing. A system for automatic submission has been crafted to send jobs to integration testbed sites, collecting the results in a central service and generating regular reports for performance and reliability.

  20. Automatic Integration Testbeds validation on Open Science Grid

    Science.gov (United States)

    Caballero, J.; Thapa, S.; Gardner, R.; Potekhin, M.

    2011-12-01

    A recurring challenge in deploying high quality production middleware is the extent to which realistic testing occurs before release of the software into the production environment. We describe here an automated system for validating releases of the Open Science Grid software stack that leverages the (pilot-based) PanDA job management system developed and used by the ATLAS experiment. The system was motivated by a desire to subject the OSG Integration Testbed to more realistic validation tests. In particular those which resemble to every extent possible actual job workflows used by the experiments thus utilizing job scheduling at the compute element (CE), use of the worker node execution environment, transfer of data to/from the local storage element (SE), etc. The context is that candidate releases of OSG compute and storage elements can be tested by injecting large numbers of synthetic jobs varying in complexity and coverage of services tested. The native capabilities of the PanDA system can thus be used to define jobs, monitor their execution, and archive the resulting run statistics including success and failure modes. A repository of generic workflows and job types to measure various metrics of interest has been created. A command-line toolset has been developed so that testbed managers can quickly submit "VO-like" jobs into the system when newly deployed services are ready for testing. A system for automatic submission has been crafted to send jobs to integration testbed sites, collecting the results in a central service and generating regular reports for performance and reliability.

  1. 77 FR 18793 - Spectrum Sharing Innovation Test-Bed Pilot Program

    Science.gov (United States)

    2012-03-28

    .... 120322212-2212-01] Spectrum Sharing Innovation Test-Bed Pilot Program AGENCY: National Telecommunications... Innovation Test-Bed pilot program to assess whether devices employing Dynamic Spectrum Access techniques can... Spectrum Sharing Innovation Test-Bed (Test-Bed) pilot program to examine the feasibility of increased...

  2. The Orlando TDWR testbed and airborne wind shear date comparison results

    Science.gov (United States)

    Campbell, Steven; Berke, Anthony; Matthews, Michael

    1992-01-01

    The focus of this talk is on comparing terminal Doppler Weather Radar (TDWR) and airborne wind shear data in computing a microburst hazard index called the F factor. The TDWR is a ground-based system for detecting wind shear hazards to aviation in the terminal area. The Federal Aviation Administration will begin deploying TDWR units near 45 airports in late 1992. As part of this development effort, M.I.T. Lincoln Laboratory operates under F.A.A. support a TDWR testbed radar in Orlando, FL. During the past two years, a series of flight tests has been conducted with instrumented aircraft penetrating microburst events while under testbed radar surveillance. These tests were carried out with a Cessna Citation 2 aircraft operated by the University of North Dakota (UND) Center for Aerospace Sciences in 1990, and a Boeing 737 operated by NASA Langley Research Center in 1991. A large data base of approximately 60 instrumented microburst penetrations has been obtained from these flights.

  3. Building a ROS-Based Testbed for Realistic Multi-Robot Simulation: Taking the Exploration as an Example

    Directory of Open Access Journals (Sweden)

    Zhi Yan

    2017-09-01

    Full Text Available While the robotics community agrees that the benchmarking is of high importance to objectively compare different solutions, there are only few and limited tools to support it. To address this issue in the context of multi-robot systems, we have defined a benchmarking process based on experimental designs, which aimed at improving the reproducibility of experiments by making explicit all elements of a benchmark such as parameters, measurements and metrics. We have also developed a ROS (Robot Operating System-based testbed with the goal of making it easy for users to validate, benchmark, and compare different algorithms including coordination strategies. Our testbed uses the MORSE (Modular OpenRobots Simulation Engine simulator for realistic simulation and a computer cluster for decentralized computation. In this paper, we present our testbed in details with the architecture and infrastructure, the issues encountered in implementing the infrastructure, and the automation of the deployment. We also report a series of experiments on multi-robot exploration, in order to demonstrate the capabilities of our testbed.

  4. Virtual Factory Testbed

    Data.gov (United States)

    Federal Laboratory Consortium — The Virtual Factory Testbed (VFT) is comprised of three physical facilities linked by a standalone network (VFNet). The three facilities are the Smart and Wireless...

  5. NBodyLab: A Testbed for Undergraduates Utilizing a Web Interface to NEMO and MD-GRAPE2 Hardware

    Science.gov (United States)

    Johnson, V. L.; Teuben, P. J.; Penprase, B. E.

    An N-body simulation testbed called NBodyLab was developed at Pomona College as a teaching tool for undergraduates. The testbed runs under Linux and provides a web interface to selected back-end NEMO modeling and analysis tools, and several integration methods which can optionally use an MD-GRAPE2 supercomputer card in the server to accelerate calculation of particle-particle forces. The testbed provides a framework for using and experimenting with the main components of N-body simulations: data models and transformations, numerical integration of the equations of motion, analysis and visualization products, and acceleration techniques (in this case, special purpose hardware). The testbed can be used by students with no knowledge of programming or Unix, freeing such students and their instructor to spend more time on scientific experimentation. The advanced student can extend the testbed software and/or more quickly transition to the use of more advanced Unix-based toolsets such as NEMO, Starlab and model builders such as GalactICS. Cosmology students at Pomona College used the testbed to study collisions of galaxies with different speeds, masses, densities, collision angles, angular momentum, etc., attempting to simulate, for example, the Tadpole Galaxy and the Antenna Galaxies. The testbed framework is available as open-source to assist other researchers and educators. Recommendations are made for testbed enhancements.

  6. BEATBOX v1.0: Background Error Analysis Testbed with Box Models

    Science.gov (United States)

    Knote, Christoph; Barré, Jérôme; Eckl, Max

    2018-02-01

    The Background Error Analysis Testbed (BEATBOX) is a new data assimilation framework for box models. Based on the BOX Model eXtension (BOXMOX) to the Kinetic Pre-Processor (KPP), this framework allows users to conduct performance evaluations of data assimilation experiments, sensitivity analyses, and detailed chemical scheme diagnostics from an observation simulation system experiment (OSSE) point of view. The BEATBOX framework incorporates an observation simulator and a data assimilation system with the possibility of choosing ensemble, adjoint, or combined sensitivities. A user-friendly, Python-based interface allows for the tuning of many parameters for atmospheric chemistry and data assimilation research as well as for educational purposes, for example observation error, model covariances, ensemble size, perturbation distribution in the initial conditions, and so on. In this work, the testbed is described and two case studies are presented to illustrate the design of a typical OSSE experiment, data assimilation experiments, a sensitivity analysis, and a method for diagnosing model errors. BEATBOX is released as an open source tool for the atmospheric chemistry and data assimilation communities.

  7. BEATBOX v1.0: Background Error Analysis Testbed with Box Models

    Directory of Open Access Journals (Sweden)

    C. Knote

    2018-02-01

    Full Text Available The Background Error Analysis Testbed (BEATBOX is a new data assimilation framework for box models. Based on the BOX Model eXtension (BOXMOX to the Kinetic Pre-Processor (KPP, this framework allows users to conduct performance evaluations of data assimilation experiments, sensitivity analyses, and detailed chemical scheme diagnostics from an observation simulation system experiment (OSSE point of view. The BEATBOX framework incorporates an observation simulator and a data assimilation system with the possibility of choosing ensemble, adjoint, or combined sensitivities. A user-friendly, Python-based interface allows for the tuning of many parameters for atmospheric chemistry and data assimilation research as well as for educational purposes, for example observation error, model covariances, ensemble size, perturbation distribution in the initial conditions, and so on. In this work, the testbed is described and two case studies are presented to illustrate the design of a typical OSSE experiment, data assimilation experiments, a sensitivity analysis, and a method for diagnosing model errors. BEATBOX is released as an open source tool for the atmospheric chemistry and data assimilation communities.

  8. Development of a space-systems network testbed

    Science.gov (United States)

    Lala, Jaynarayan; Alger, Linda; Adams, Stuart; Burkhardt, Laura; Nagle, Gail; Murray, Nicholas

    1988-01-01

    This paper describes a communications network testbed which has been designed to allow the development of architectures and algorithms that meet the functional requirements of future NASA communication systems. The central hardware components of the Network Testbed are programmable circuit switching communication nodes which can be adapted by software or firmware changes to customize the testbed to particular architectures and algorithms. Fault detection, isolation, and reconfiguration has been implemented in the Network with a hybrid approach which utilizes features of both centralized and distributed techniques to provide efficient handling of faults within the Network.

  9. Dynamic Testing of the NASA Hypersonic Project Combined Cycle Engine Testbed for Mode Transition Experiments

    Science.gov (United States)

    2011-01-01

    NASA is interested in developing technology that leads to more routine, safe, and affordable access to space. Access to space using airbreathing propulsion systems has potential to meet these objectives based on Airbreathing Access to Space (AAS) system studies. To this end, the NASA Fundamental Aeronautics Program (FAP) Hypersonic Project is conducting fundamental research on a Turbine Based Combined Cycle (TBCC) propulsion system. The TBCC being studied considers a dual flow-path inlet system. One flow-path includes variable geometry to regulate airflow to a turbine engine cycle. The turbine cycle provides propulsion from take-off to supersonic flight. The second flow-path supports a dual-mode scramjet (DMSJ) cycle which would be initiated at supersonic speed to further accelerate the vehicle to hypersonic speed. For a TBCC propulsion system to accelerate a vehicle from supersonic to hypersonic speed, a critical enabling technology is the ability to safely and effectively transition from the turbine to the DMSJ-referred to as mode transition. To experimentally test methods of mode transition, a Combined Cycle Engine (CCE) Large-scale Inlet testbed was designed with two flow paths-a low speed flow-path sized for a turbine cycle and a high speed flow-path designed for a DMSJ. This testbed system is identified as the CCE Large-Scale Inlet for Mode Transition studies (CCE-LIMX). The test plan for the CCE-LIMX in the NASA Glenn Research Center (GRC) 10- by 10-ft Supersonic Wind Tunnel (10x10 SWT) is segmented into multiple phases. The first phase is a matrix of inlet characterization (IC) tests to evaluate the inlet performance and establish the mode transition schedule. The second phase is a matrix of dynamic system identification (SysID) experiments designed to support closed-loop control development at mode transition schedule operating points for the CCE-LIMX. The third phase includes a direct demonstration of controlled mode transition using a closed loop control

  10. The design and implementation of the LLNL gigabit testbed

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, D. [Lawrence Livermore National Labs., CA (United States)

    1994-12-01

    This paper will look at the design and implementation of the LLNL Gigabit testbed (LGTB), where various high speed networking products, can be tested in one environment. The paper will discuss the philosophy behind the design of and the need for the testbed, the tests that are performed in the testbed, and the tools used to implement those tests.

  11. Development of a hardware-in-the-loop testbed to demonstrate multiple spacecraft operations in proximity

    Science.gov (United States)

    Eun, Youngho; Park, Sang-Young; Kim, Geuk-Nam

    2018-06-01

    This paper presents a new state-of-the-art ground-based hardware-in-the-loop test facility, which was developed to verify and demonstrate autonomous guidance, navigation, and control algorithms for space proximity operations and formation flying maneuvers. The test facility consists of two complete spaceflight simulators, an aluminum-based operational arena, and a set of infrared motion tracking cameras; thus, the testbed is capable of representing space activities under circumstances prevailing on the ground. The spaceflight simulators have a maximum of five-degree-of-freedom in a quasi-momentum-free environment, which is produced by a set of linear/hemispherical air-bearings and a horizontally leveled operational arena. The tracking system measures the real-time three-dimensional position and attitude to provide state variables to the agents. The design of the testbed is illustrated in detail for every element throughout the paper. The practical hardware characteristics of the active/passive measurement units and internal actuators are identified in detail from various perspectives. These experimental results support the successful development of the entire facility and enable us to implement and verify the spacecraft proximity operation strategy in the near future.

  12. The Living With a Star Program Space Environment Testbed

    Science.gov (United States)

    Barth, Janet; Day, John H. (Technical Monitor)

    2001-01-01

    This viewgraph presentation describes the objective, approach, and scope of the Living With a Star (LWS) program at the Marshall Space Flight Center. Scientists involved in the project seek to refine the understanding of space weather and the role of solar variability in terrestrial climate change. Research and the development of improved analytic methods have led to increased predictive capabilities and the improvement of environment specification models. Specifically, the Space Environment Testbed (SET) project of LWS is responsible for the implementation of improved engineering approaches to observing solar effects on climate change. This responsibility includes technology development, ground test protocol development, and the development of a technology application model/engineering tool.

  13. Solar Resource Assessment with Sky Imagery and a Virtual Testbed for Sky Imager Solar Forecasting

    Science.gov (United States)

    Kurtz, Benjamin Bernard

    In recent years, ground-based sky imagers have emerged as a promising tool for forecasting solar energy on short time scales (0 to 30 minutes ahead). Following the development of sky imager hardware and algorithms at UC San Diego, we present three new or improved algorithms for sky imager forecasting and forecast evaluation. First, we present an algorithm for measuring irradiance with a sky imager. Sky imager forecasts are often used in conjunction with other instruments for measuring irradiance, so this has the potential to decrease instrumentation costs and logistical complexity. In particular, the forecast algorithm itself often relies on knowledge of the current irradiance which can now be provided directly from the sky images. Irradiance measurements are accurate to within about 10%. Second, we demonstrate a virtual sky imager testbed that can be used for validating and enhancing the forecast algorithm. The testbed uses high-quality (but slow) simulations to produce virtual clouds and sky images. Because virtual cloud locations are known, much more advanced validation procedures are possible with the virtual testbed than with measured data. In this way, we are able to determine that camera geometry and non-uniform evolution of the cloud field are the two largest sources of forecast error. Finally, with the assistance of the virtual sky imager testbed, we develop improvements to the cloud advection model used for forecasting. The new advection schemes are 10-20% better at short time horizons.

  14. A Battery Certification Testbed for Small Satellite Missions

    Science.gov (United States)

    Cameron, Zachary; Kulkarni, Chetan S.; Luna, Ali Guarneros; Goebel, Kai; Poll, Scott

    2015-01-01

    A battery pack consisting of standard cylindrical 18650 lithium-ion cells has been chosen for small satellite missions based on previous flight heritage and compliance with NASA battery safety requirements. However, for batteries that transit through the International Space Station (ISS), additional certification tests are required for individual cells as well as the battery packs. In this manuscript, we discuss the development of generalized testbeds for testing and certifying different types of batteries critical to small satellite missions. Test procedures developed and executed for this certification effort include: a detailed physical inspection before and after experiments; electrical cycling characterization at the cell and pack levels; battery-pack overcharge, over-discharge, external short testing; battery-pack vacuum leak and vibration testing. The overall goals of these certification procedures are to conform to requirements set forth by the agency and identify unique safety hazards. The testbeds, procedures, and experimental results are discussed for batteries chosen for small satellite missions to be launched from the ISS.

  15. The end-to-end testbed of the optical metrology system on-board LISA Pathfinder

    Energy Technology Data Exchange (ETDEWEB)

    Steier, F; Cervantes, F Guzman; Marin, A F GarcIa; Heinzel, G; Danzmann, K [Max-Planck-Institut fuer Gravitationsphysik (Albert-Einstein-Institut) and Universitaet Hannover (Germany); Gerardi, D, E-mail: frank.steier@aei.mpg.d [EADS Astrium Satellites GmbH, Friedrichshafen (Germany)

    2009-05-07

    LISA Pathfinder is a technology demonstration mission for the Laser Interferometer Space Antenna (LISA). The main experiment on-board LISA Pathfinder is the so-called LISA Technology Package (LTP) which has the aim to measure the differential acceleration between two free-falling test masses with an accuracy of 3 x 10{sup -14} ms{sup -2} Hz{sup -1/2} between 1 mHz and 30 mHz. This measurement is performed interferometrically by the optical metrology system (OMS) on-board LISA Pathfinder. In this paper, we present the development of an experimental end-to-end testbed of the entire OMS. It includes the interferometer and its sub-units, the interferometer backend which is a phasemeter and the processing of the phasemeter output data. Furthermore, three-axes piezo-actuated mirrors are used instead of the free-falling test masses for the characterization of the dynamic behaviour of the system and some parts of the drag-free and attitude control system (DFACS) which controls the test masses and the satellite. The end-to-end testbed includes all parts of the LTP that can reasonably be tested on earth without free-falling test masses. At its present status it consists mainly of breadboard components. Some of those have already been replaced by engineering models of the LTP experiment. In the next steps, further engineering and flight models will also be inserted in this testbed and tested against well-characterized breadboard components. The presented testbed is an important reference for the unit tests and can also be used for validation of the on-board experiment during the mission.

  16. The Objectives of NASA's Living with a Star Space Environment Testbed

    Science.gov (United States)

    Barth, Janet L.; LaBel, Kenneth A.; Brewer, Dana; Kauffman, Billy; Howard, Regan; Griffin, Geoff; Day, John H. (Technical Monitor)

    2001-01-01

    NASA is planning to fly a series of Space Environment Testbeds (SET) as part of the Living With A Star (LWS) Program. The goal of the testbeds is to improve and develop capabilities to mitigate and/or accommodate the affects of solar variability in spacecraft and avionics design and operation. This will be accomplished by performing technology validation in space to enable routine operations, characterize technology performance in space, and improve and develop models, guidelines and databases. The anticipated result of the LWS/SET program is improved spacecraft performance, design, and operation for survival of the radiation, spacecraft charging, meteoroid, orbital debris and thermosphere/ionosphere environments. The program calls for a series of NASA Research Announcements (NRAs) to be issued to solicit flight validation experiments, improvement in environment effects models and guidelines, and collateral environment measurements. The selected flight experiments may fly on the SET experiment carriers and flights of opportunity on other commercial and technology missions. This paper presents the status of the project so far, including a description of the types of experiments that are intended to fly on SET-1 and a description of the SET-1 carrier parameters.

  17. Advanced Artificial Intelligence Technology Testbed

    Science.gov (United States)

    Anken, Craig S.

    1993-01-01

    The Advanced Artificial Intelligence Technology Testbed (AAITT) is a laboratory testbed for the design, analysis, integration, evaluation, and exercising of large-scale, complex, software systems, composed of both knowledge-based and conventional components. The AAITT assists its users in the following ways: configuring various problem-solving application suites; observing and measuring the behavior of these applications and the interactions between their constituent modules; gathering and analyzing statistics about the occurrence of key events; and flexibly and quickly altering the interaction of modules within the applications for further study.

  18. Distributed computing testbed for a remote experimental environment

    International Nuclear Information System (INIS)

    Butner, D.N.; Casper, T.A.; Howard, B.C.; Henline, P.A.; Davis, S.L.; Barnes, D.

    1995-01-01

    Collaboration is increasing as physics research becomes concentrated on a few large, expensive facilities, particularly in magnetic fusion energy research, with national and international participation. These facilities are designed for steady state operation and interactive, real-time experimentation. We are developing tools to provide for the establishment of geographically distant centers for interactive operations; such centers would allow scientists to participate in experiments from their home institutions. A testbed is being developed for a Remote Experimental Environment (REE), a ''Collaboratory.'' The testbed will be used to evaluate the ability of a remotely located group of scientists to conduct research on the DIII-D Tokamak at General Atomics. The REE will serve as a testing environment for advanced control and collaboration concepts applicable to future experiments. Process-to-process communications over high speed wide area networks provide real-time synchronization and exchange of data among multiple computer networks, while the ability to conduct research is enhanced by adding audio/video communication capabilities. The Open Software Foundation's Distributed Computing Environment is being used to test concepts in distributed control, security, naming, remote procedure calls and distributed file access using the Distributed File Services. We are exploring the technology and sociology of remotely participating in the operation of a large scale experimental facility

  19. Environment Emulation For Wsn Testbed

    Directory of Open Access Journals (Sweden)

    Radosław Kapłoniak

    2012-01-01

    Full Text Available The development of applications for wireless sensor networks is a challenging task. For this reason, several testbed platforms have been created. They simplify the manageability of nodes by offering easy ways of programming and debugging sensor nodes. These platforms, sometimes composed of dozens of sensors, provide a convenient way for carrying out research on medium access control and data exchange between nodes. In this article, we propose the extension of the WSN testbed, which could be used for evaluating and testing the functionality of sensor networks applications by emulating a real-world environment.

  20. MIT-NASA/KSC space life science experiments - A telescience testbed

    Science.gov (United States)

    Oman, Charles M.; Lichtenberg, Byron K.; Fiser, Richard L.; Vordermark, Deborah S.

    1990-01-01

    Experiments performed at MIT to better define Space Station information system telescience requirements for effective remote coaching of astronauts by principal investigators (PI) on the ground are described. The experiments were conducted via satellite video, data, and voice links to surrogate crewmembers working in a laboratory at NASA's Kennedy Space Center. Teams of two PIs and two crewmembers performed two different space life sciences experiments. During 19 three-hour interactive sessions, a variety of test conditions were explored. Since bit rate limits are necessarily imposed on Space Station video experiments surveillance video was varied down to 50 Kb/s and the effectiveness of PI controlled frame rate, resolution, grey scale, and color decimation was investigated. It is concluded that remote coaching by voice works and that dedicated crew-PI voice loops would be of great value on the Space Station.

  1. Dr. Tulga Ersal at NSF Workshop Accessible Remote Testbeds ART'15

    Science.gov (United States)

    Event Archives Dr. Tulga Ersal at NSF Workshop Accessible Remote Testbeds ART'15 On November 12th, Dr Workshop on Accessible Remote Testbeds (ART'15) at Georgia Tech. From the event website: The rationale behind the ART'15 workshop is that remote-access testbeds could, if done right, significantly change how

  2. SSERVI Analog Regolith Simulant Testbed Facility

    Science.gov (United States)

    Minafra, J.; Schmidt, G. K.

    2016-12-01

    SSERVI's goals include supporting planetary researchers within NASA, other government agencies; private sector and hardware developers; competitors in focused prize design competitions; and academic sector researchers. The SSERVI Analog Regolith Simulant Testbed provides opportunities for research scientists and engineers to study the effects of regolith analog testbed research in the planetary exploration field. This capability is essential to help to understand the basic effects of continued long-term exposure to a simulated analog test environment. The current facility houses approximately eight tons of JSC-1A lunar regolith simulant in a test bin consisting of a 4 meter by 4 meter area. SSERVI provides a bridge between several groups, joining together researchers from: 1) scientific and exploration communities, 2) multiple disciplines across a wide range of planetary sciences, and 3) domestic and international communities and partnerships. This testbed provides a means of consolidating the tasks of acquisition, storage and safety mitigation in handling large quantities of regolith simulant Facility hardware and environment testing scenarios include, but are not limited to the following; Lunar surface mobility, Dust exposure and mitigation, Regolith handling and excavation, Solar-like illumination, Lunar surface compaction profile, Lofted dust, Mechanical properties of lunar regolith, and Surface features (i.e. grades and rocks) Numerous benefits vary from easy access to a controlled analog regolith simulant testbed, and planetary exploration activities at NASA Research Park, to academia and expanded commercial opportunities in California's Silicon Valley, as well as public outreach and education opportunities.

  3. Optical Network Testbeds Workshop

    Energy Technology Data Exchange (ETDEWEB)

    Joe Mambretti

    2007-06-01

    This is the summary report of the third annual Optical Networking Testbed Workshop (ONT3), which brought together leading members of the international advanced research community to address major challenges in creating next generation communication services and technologies. Networking research and development (R&D) communities throughout the world continue to discover new methods and technologies that are enabling breakthroughs in advanced communications. These discoveries are keystones for building the foundation of the future economy, which requires the sophisticated management of extremely large qualities of digital information through high performance communications. This innovation is made possible by basic research and experiments within laboratories and on specialized testbeds. Initial network research and development initiatives are driven by diverse motives, including attempts to solve existing complex problems, the desire to create powerful new technologies that do not exist using traditional methods, and the need to create tools to address specific challenges, including those mandated by large scale science or government agency mission agendas. Many new discoveries related to communications technologies transition to wide-spread deployment through standards organizations and commercialization. These transition paths allow for new communications capabilities that drive many sectors of the digital economy. In the last few years, networking R&D has increasingly focused on advancing multiple new capabilities enabled by next generation optical networking. Both US Federal networking R&D and other national R&D initiatives, such as those organized by the National Institute of Information and Communications Technology (NICT) of Japan are creating optical networking technologies that allow for new, powerful communication services. Among the most promising services are those based on new types of multi-service or hybrid networks, which use new optical networking

  4. Implementation of standard testbeds for numerical relativity

    Energy Technology Data Exchange (ETDEWEB)

    Babiuc, M C [Department of Physics and Physical Science, Marshall University, Huntington, WV 25755 (United States); Husa, S [Friedrich Schiller University Jena, Max-Wien-Platz 1, 07743 Jena (Germany); Alic, D [Department of Physics, University of the Balearic Islands, Cra Valldemossa km 7.5, 07122 Palma de Mallorca (Spain); Hinder, I [Center for Gravitational Wave Physics, Pennsylvania State University, University Park, PA 16802 (United States); Lechner, C [Weierstrass Institute for Applied Analysis and Stochastics (WIAS), Mohrenstrasse 39, 10117 Berlin (Germany); Schnetter, E [Center for Computation and Technology, 216 Johnston Hall, Louisiana State University, Baton Rouge, LA 70803 (United States); Szilagyi, B; Dorband, N; Pollney, D; Winicour, J [Max-Planck-Institut fuer Gravitationsphysik (Albert-Einstein-Institut), Am Muehlenberg 1, 14076 Golm (Germany); Zlochower, Y [Center for Computational Relativity and Gravitation, School of Mathematical Sciences, Rochester Institute of Technology, 78 Lomb Memorial Drive, Rochester, New York 14623 (United States)

    2008-06-21

    We discuss results that have been obtained from the implementation of the initial round of testbeds for numerical relativity which was proposed in the first paper of the Apples with Apples Alliance. We present benchmark results for various codes which provide templates for analyzing the testbeds and to draw conclusions about various features of the codes. This allows us to sharpen the initial test specifications, design a new test and add theoretical insight.

  5. Space Station technology testbed: 2010 deep space transport

    Science.gov (United States)

    Holt, Alan C.

    1993-01-01

    A space station in a crew-tended or permanently crewed configuration will provide major R&D opportunities for innovative, technology and materials development and advanced space systems testing. A space station should be designed with the basic infrastructure elements required to grow into a major systems technology testbed. This space-based technology testbed can and should be used to support the development of technologies required to expand our utilization of near-Earth space, the Moon and the Earth-to-Jupiter region of the Solar System. Space station support of advanced technology and materials development will result in new techniques for high priority scientific research and the knowledge and R&D base needed for the development of major, new commercial product thrusts. To illustrate the technology testbed potential of a space station and to point the way to a bold, innovative approach to advanced space systems' development, a hypothetical deep space transport development and test plan is described. Key deep space transport R&D activities are described would lead to the readiness certification of an advanced, reusable interplanetary transport capable of supporting eight crewmembers or more. With the support of a focused and highly motivated, multi-agency ground R&D program, a deep space transport of this type could be assembled and tested by 2010. Key R&D activities on a space station would include: (1) experimental research investigating the microgravity assisted, restructuring of micro-engineered, materials (to develop and verify the in-space and in-situ 'tuning' of materials for use in debris and radiation shielding and other protective systems), (2) exposure of microengineered materials to the space environment for passive and operational performance tests (to develop in-situ maintenance and repair techniques and to support the development, enhancement, and implementation of protective systems, data and bio-processing systems, and virtual reality and

  6. A technical description of the FlexHouse Project Testbed

    DEFF Research Database (Denmark)

    Sørensen, Jens Otto

    2000-01-01

    This paper describes the FlexHouse project testbed; a server dedicated to experiments within the FlexHouse project. The FlexHouse project is a project originating from The Business Computing Research Group at The Aarhus School of Business. The purpose of the project is to identify and develop...... methods that satisfy the following three requirements. Flexibility with respect to evolving data sources. Flexibility with respect to change of information needs. Efficiency with respect to view management....

  7. Design, Development, and Testing of a UAV Hardware-in-the-Loop Testbed for Aviation and Airspace Prognostics Research

    Science.gov (United States)

    Kulkarni, Chetan; Teubert, Chris; Gorospe, George; Burgett, Drew; Quach, Cuong C.; Hogge, Edward

    2016-01-01

    The airspace is becoming more and more complicated, and will continue to do so in the future with the integration of Unmanned Aerial Vehicles (UAVs), autonomy, spacecraft, other forms of aviation technology into the airspace. The new technology and complexity increases the importance and difficulty of safety assurance. Additionally, testing new technologies on complex aviation systems & systems of systems can be very difficult, expensive, and sometimes unsafe in real life scenarios. Prognostic methodology provides an estimate of the health and risks of a component, vehicle, or airspace and knowledge of how that will change over time. That measure is especially useful in safety determination, mission planning, and maintenance scheduling. The developed testbed will be used to validate prediction algorithms for the real-time safety monitoring of the National Airspace System (NAS) and the prediction of unsafe events. The framework injects flight related anomalies related to ground systems, routing, airport congestion, etc. to test and verify algorithms for NAS safety. In our research work, we develop a live, distributed, hardware-in-the-loop testbed for aviation and airspace prognostics along with exploring further research possibilities to verify and validate future algorithms for NAS safety. The testbed integrates virtual aircraft using the X-Plane simulator and X-PlaneConnect toolbox, UAVs using onboard sensors and cellular communications, and hardware in the loop components. In addition, the testbed includes an additional research framework to support and simplify future research activities. It enables safe, accurate, and inexpensive experimentation and research into airspace and vehicle prognosis that would not have been possible otherwise. This paper describes the design, development, and testing of this system. Software reliability, safety and latency are some of the critical design considerations in development of the testbed. Integration of HITL elements in

  8. CRYogenic Orbital TEstbed Ground Test Article Thermal Analysis

    Science.gov (United States)

    Piryk, David; Schallhorn, Paul; Walls, Laurie; Stopnitzky, Benny; Rhys, Noah; Wollen, Mark

    2012-01-01

    The purpose of this study was to anchor thermal and fluid system models to CRYOTE ground test data. The CRYOTE ground test artide was jointly developed by Innovative Engineering Solutions, United Launch Alliance and NASA KSC. The test article was constructed out of a titanium alloy tank, Sapphire 77 composite skin (similar to G10), an external secondary payload adapter ring, thermal vent system, multi layer insulation and various data acquisition instrumentation. In efforts to understand heat loads throughout this system, the GTA (filled with liquid nitrogen for safety purposes) was subjected to a series of tests in a vacuum chamber at Marshall Space Flight Center. By anchoring analytical models against test data, higher fidelity thermal environment predictions can be made for future flight articles which would eventually demonstrate critical cryogenic fluid management technologies such as system chilldown, transfer, pressure control and long term storage. Significant factors that influenced heat loads included radiative environments, multi-layer insulation performance, tank fill levels and pressures and even contact conductance coefficients. This report demonstrates how analytical thermal/fluid networks were established and includes supporting rationale for specific thermal responses.

  9. Interactive aircraft cabin testbed for stress-free air travel system experiment: an innovative concurrent design approach

    NARCIS (Netherlands)

    Tan, C.F.; Chen, W.; Rauterberg, G.W.M.

    2009-01-01

    In this paper, a study of the concurrent engineering design for the environmental friendly low cost aircraft cabin simulator is presented. The study describes the used of concurrent design technique in the design activity. The simulator is a testbed that was designed and built for research on

  10. A Novel UAV Electric Propulsion Testbed for Diagnostics and Prognostics

    Science.gov (United States)

    Gorospe, George E., Jr.; Kulkarni, Chetan S.

    2017-01-01

    This paper presents a novel hardware-in-the-loop (HIL) testbed for systems level diagnostics and prognostics of an electric propulsion system used in UAVs (unmanned aerial vehicle). Referencing the all electric, Edge 540T aircraft used in science and research by NASA Langley Flight Research Center, the HIL testbed includes an identical propulsion system, consisting of motors, speed controllers and batteries. Isolated under a controlled laboratory environment, the propulsion system has been instrumented for advanced diagnostics and prognostics. To produce flight like loading on the system a slave motor is coupled to the motor under test (MUT) and provides variable mechanical resistance, and the capability of introducing nondestructive mechanical wear-like frictional loads on the system. This testbed enables the verification of mathematical models of each component of the propulsion system, the repeatable generation of flight-like loads on the system for fault analysis, test-to-failure scenarios, and the development of advanced system level diagnostics and prognostics methods. The capabilities of the testbed are extended through the integration of a LabVIEW-based client for the Live Virtual Constructive Distributed Environment (LVCDC) Gateway which enables both the publishing of generated data for remotely located observers and prognosers and the synchronization the testbed propulsion system with vehicles in the air. The developed HIL testbed gives researchers easy access to a scientifically relevant portion of the aircraft without the overhead and dangers encountered during actual flight.

  11. Large Scale Data Mining to Improve Usability of Data: An Intelligent Archive Testbed

    Science.gov (United States)

    Ramapriyan, Hampapuram; Isaac, David; Yang, Wenli; Morse, Steve

    2005-01-01

    Research in certain scientific disciplines - including Earth science, particle physics, and astrophysics - continually faces the challenge that the volume of data needed to perform valid scientific research can at times overwhelm even a sizable research community. The desire to improve utilization of this data gave rise to the Intelligent Archives project, which seeks to make data archives active participants in a knowledge building system capable of discovering events or patterns that represent new information or knowledge. Data mining can automatically discover patterns and events, but it is generally viewed as unsuited for large-scale use in disciplines like Earth science that routinely involve very high data volumes. Dozens of research projects have shown promising uses of data mining in Earth science, but all of these are based on experiments with data subsets of a few gigabytes or less, rather than the terabytes or petabytes typically encountered in operational systems. To bridge this gap, the Intelligent Archives project is establishing a testbed with the goal of demonstrating the use of data mining techniques in an operationally-relevant environment. This paper discusses the goals of the testbed and the design choices surrounding critical issues that arose during testbed implementation.

  12. Smart Antenna UKM Testbed for Digital Beamforming System

    Directory of Open Access Journals (Sweden)

    2009-03-01

    Full Text Available A new design of smart antenna testbed developed at UKM for digital beamforming purpose is proposed. The smart antenna UKM testbed developed based on modular design employing two novel designs of L-probe fed inverted hybrid E-H (LIEH array antenna and software reconfigurable digital beamforming system (DBS. The antenna is developed based on using the novel LIEH microstrip patch element design arranged into 4×1 uniform linear array antenna. An interface board is designed to interface to the ADC board with the RF front-end receiver. The modular concept of the system provides the capability to test the antenna hardware, beamforming unit, and beamforming algorithm in an independent manner, thus allowing the smart antenna system to be developed and tested in parallel, hence reduces the design time. The DBS was developed using a high-performance TMS320C6711TM floating-point DSP board and a 4-channel RF front-end receiver developed in-house. An interface board is designed to interface to the ADC board with the RF front-end receiver. A four-element receiving array testbed at 1.88–2.22 GHz frequency is constructed, and digital beamforming on this testbed is successfully demonstrated.

  13. Development of a Tethered Formation Flight Testbed for ISS, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The development of a testbed for the development and demonstration of technologies needed by tethered formation flying satellites is proposed. Such a testbed would...

  14. SSERVI Analog Regolith Simulant Testbed Facility

    Science.gov (United States)

    Minafra, Joseph; Schmidt, Gregory; Bailey, Brad; Gibbs, Kristina

    2016-10-01

    The Solar System Exploration Research Virtual Institute (SSERVI) at NASA's Ames Research Center in California's Silicon Valley was founded in 2013 to act as a virtual institute that provides interdisciplinary research centered on the goals of its supporting directorates: NASA Science Mission Directorate (SMD) and the Human Exploration & Operations Mission Directorate (HEOMD).Primary research goals of the Institute revolve around the integration of science and exploration to gain knowledge required for the future of human space exploration beyond low Earth orbit. SSERVI intends to leverage existing JSC1A regolith simulant resources into the creation of a regolith simulant testbed facility. The purpose of this testbed concept is to provide the planetary exploration community with a readily available capability to test hardware and conduct research in a large simulant environment.SSERVI's goals include supporting planetary researchers within NASA, other government agencies; private sector and hardware developers; competitors in focused prize design competitions; and academic sector researchers.SSERVI provides opportunities for research scientists and engineers to study the effects of regolith analog testbed research in the planetary exploration field. This capability is essential to help to understand the basic effects of continued long-term exposure to a simulated analog test environment.The current facility houses approximately eight tons of JSC-1A lunar regolith simulant in a test bin consisting of a 4 meter by 4 meter area, including dust mitigation and safety oversight.Facility hardware and environment testing scenarios could include, Lunar surface mobility, Dust exposure and mitigation, Regolith handling and excavation, Solar-like illumination, Lunar surface compaction profile, Lofted dust, Mechanical properties of lunar regolith, Surface features (i.e. grades and rocks)Numerous benefits vary from easy access to a controlled analog regolith simulant testbed, and

  15. Wavefront control performance modeling with WFIRST shaped pupil coronagraph testbed

    Science.gov (United States)

    Zhou, Hanying; Nemati, Bijian; Krist, John; Cady, Eric; Kern, Brian; Poberezhskiy, Ilya

    2017-09-01

    NASA's WFIRST mission includes a coronagraph instrument (CGI) for direct imaging of exoplanets. Significant improvement in CGI model fidelity has been made recently, alongside a testbed high contrast demonstration in a simulated dynamic environment at JPL. We present our modeling method and results of comparisons to testbed's high order wavefront correction performance for the shaped pupil coronagraph. Agreement between model prediction and testbed result at better than a factor of 2 has been consistently achieved in raw contrast (contrast floor, chromaticity, and convergence), and with that comes good agreement in contrast sensitivity to wavefront perturbations and mask lateral shear.

  16. Evaluation of Unmanned Aircraft Systems (UAS) for Weather and Climate using the Multi-testbed approach

    Science.gov (United States)

    Baker, B.; Lee, T.; Buban, M.; Dumas, E. J.

    2017-12-01

    Evaluation of Unmanned Aircraft Systems (UAS) for Weather and Climate using the Multi-testbed approachC. Bruce Baker1, Ed Dumas1,2, Temple Lee1,2, Michael Buban1,21NOAA ARL, Atmospheric Turbulence and Diffusion Division, Oak Ridge, TN2Oak Ridge Associated Universities, Oak Ridge, TN The development of a small Unmanned Aerial System (sUAS) testbeds that can be used to validate, integrate, calibrate and evaluate new technology and sensors for routine boundary layer research, validation of operational weather models, improvement of model parameterizations, and recording observations within high-impact storms is important for understanding the importance and impact of using sUAS's routinely as a new observing platform. The goal of the multi-testbed approach is to build a robust set of protocols to assess the cost and operational feasibility of unmanned observations for routine applications using various combinations of sUAS aircraft and sensors in different locations and field experiments. All of these observational testbeds serve different community needs, but they also use a diverse suite of methodologies for calibration and evaluation of different sensors and platforms for severe weather and boundary layer research. The primary focus will be to evaluate meteorological sensor payloads to measure thermodynamic parameters and define surface characteristics with visible, IR, and multi-spectral cameras. This evaluation will lead to recommendations for sensor payloads for VTOL and fixed-wing sUAS.

  17. EPIC: A Testbed for Scientifically Rigorous Cyber-Physical Security Experimentation

    OpenAIRE

    SIATERLIS CHRISTOS; GENGE BELA; HOHENADEL MARC

    2013-01-01

    Recent malware, like Stuxnet and Flame, constitute a major threat to Networked Critical Infrastructures (NCIs), e.g., power plants. They revealed several vulnerabilities in today's NCIs, but most importantly they highlighted the lack of an efficient scientific approach to conduct experiments that measure the impact of cyber threats on both the physical and the cyber parts of NCIs. In this paper we present EPIC, a novel cyber-physical testbed and a modern scientific instrument that can pr...

  18. BigBOSS: The Ground-Based Stage IV BAO Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Schlegel, David; Bebek, Chris; Heetderks, Henry; Ho, Shirley; Lampton, Michael; Levi, Michael; Mostek, Nick; Padmanabhan, Nikhil; Perlmutter, Saul; Roe, Natalie; Sholl, Michael; Smoot, George; White, Martin; Dey, Arjun; Abraham, Tony; Jannuzi, Buell; Joyce, Dick; Liang, Ming; Merrill, Mike; Olsen, Knut; Salim, Samir

    2009-04-01

    The BigBOSS experiment is a proposed DOE-NSF Stage IV ground-based dark energy experiment to study baryon acoustic oscillations (BAO) and the growth of structure with an all-sky galaxy redshift survey. The project is designed to unlock the mystery of dark energy using existing ground-based facilities operated by NOAO. A new 4000-fiber R=5000 spectrograph covering a 3-degree diameter field will measure BAO and redshift space distortions in the distribution of galaxies and hydrogen gas spanning redshifts from 0.2< z< 3.5. The Dark Energy Task Force figure of merit (DETF FoM) for this experiment is expected to be equal to that of a JDEM mission for BAO with the lower risk and cost typical of a ground-based experiment.

  19. Towards standard testbeds for numerical relativity

    International Nuclear Information System (INIS)

    Alcubierre, Miguel; Allen, Gabrielle; Bona, Carles; Fiske, David; Goodale, Tom; Guzman, F Siddhartha; Hawke, Ian; Hawley, Scott H; Husa, Sascha; Koppitz, Michael; Lechner, Christiane; Pollney, Denis; Rideout, David; Salgado, Marcelo; Schnetter, Erik; Seidel, Edward; Shinkai, Hisa-aki; Shoemaker, Deirdre; Szilagyi, Bela; Takahashi, Ryoji; Winicour, Jeff

    2004-01-01

    In recent years, many different numerical evolution schemes for Einstein's equations have been proposed to address stability and accuracy problems that have plagued the numerical relativity community for decades. Some of these approaches have been tested on different spacetimes, and conclusions have been drawn based on these tests. However, differences in results originate from many sources, including not only formulations of the equations, but also gauges, boundary conditions, numerical methods and so on. We propose to build up a suite of standardized testbeds for comparing approaches to the numerical evolution of Einstein's equations that are designed to both probe their strengths and weaknesses and to separate out different effects, and their causes, seen in the results. We discuss general design principles of suitable testbeds, and we present an initial round of simple tests with periodic boundary conditions. This is a pivotal first step towards building a suite of testbeds to serve the numerical relativists and researchers from related fields who wish to assess the capabilities of numerical relativity codes. We present some examples of how these tests can be quite effective in revealing various limitations of different approaches, and illustrating their differences. The tests are presently limited to vacuum spacetimes, can be run on modest computational resources and can be used with many different approaches used in the relativity community

  20. Towards standard testbeds for numerical relativity

    Energy Technology Data Exchange (ETDEWEB)

    Alcubierre, Miguel [Inst. de Ciencias Nucleares, Univ. Nacional Autonoma de Mexico, Apartado Postal 70-543, Mexico Distrito Federal 04510 (Mexico); Allen, Gabrielle; Goodale, Tom; Guzman, F Siddhartha; Hawke, Ian; Husa, Sascha; Koppitz, Michael; Lechner, Christiane; Pollney, Denis; Rideout, David [Max-Planck-Inst. fuer Gravitationsphysik, Albert-Einstein-Institut, 14476 Golm (Germany); Bona, Carles [Departament de Fisica, Universitat de les Illes Balears, Ctra de Valldemossa km 7.5, 07122 Palma de Mallorca (Spain); Fiske, David [Dept. of Physics, Univ. of Maryland, College Park, MD 20742-4111 (United States); Hawley, Scott H [Center for Relativity, Univ. of Texas at Austin, Austin, Texas 78712 (United States); Salgado, Marcelo [Inst. de Ciencias Nucleares, Univ. Nacional Autonoma de Mexico, Apartado Postal 70-543, Mexico Distrito Federal 04510 (Mexico); Schnetter, Erik [Inst. fuer Astronomie und Astrophysik, Universitaet Tuebingen, 72076 Tuebingen (Germany); Seidel, Edward [Max-Planck-Inst. fuer Gravitationsphysik, Albert-Einstein-Inst., 14476 Golm (Germany); Shinkai, Hisa-aki [Computational Science Div., Inst. of Physical and Chemical Research (RIKEN), Hirosawa 2-1, Wako, Saitama 351-0198 (Japan); Shoemaker, Deirdre [Center for Radiophysics and Space Research, Cornell Univ., Ithaca, NY 14853 (United States); Szilagyi, Bela [Dept. of Physics and Astronomy, Univ. of Pittsburgh, Pittsburgh, PA 15260 (United States); Takahashi, Ryoji [Theoretical Astrophysics Center, Juliane Maries Vej 30, 2100 Copenhagen, (Denmark); Winicour, Jeff [Max-Planck-Inst. fuer Gravitationsphysik, Albert-Einstein-Institut, 14476 Golm (Germany)

    2004-01-21

    In recent years, many different numerical evolution schemes for Einstein's equations have been proposed to address stability and accuracy problems that have plagued the numerical relativity community for decades. Some of these approaches have been tested on different spacetimes, and conclusions have been drawn based on these tests. However, differences in results originate from many sources, including not only formulations of the equations, but also gauges, boundary conditions, numerical methods and so on. We propose to build up a suite of standardized testbeds for comparing approaches to the numerical evolution of Einstein's equations that are designed to both probe their strengths and weaknesses and to separate out different effects, and their causes, seen in the results. We discuss general design principles of suitable testbeds, and we present an initial round of simple tests with periodic boundary conditions. This is a pivotal first step towards building a suite of testbeds to serve the numerical relativists and researchers from related fields who wish to assess the capabilities of numerical relativity codes. We present some examples of how these tests can be quite effective in revealing various limitations of different approaches, and illustrating their differences. The tests are presently limited to vacuum spacetimes, can be run on modest computational resources and can be used with many different approaches used in the relativity community.

  1. A Testbed For Validating the LHC Controls System Core Before Deployment

    CERN Document Server

    Nguyen Xuan, J

    2011-01-01

    Since the start-up of the LHC, it is crucial to carefully test core controls components before deploying them operationally. The Testbed of the CERN accelerator controls group was developed for this purpose. It contains different hardware (PPC, i386) running various operating systems (Linux and LynxOS) and core software components running on front-ends, communication middleware and client libraries. The Testbed first executes integration tests to verify that the components delivered by individual teams interoperate, and then system tests, which verify high-level, end-user functionality. It also verifies that different versions of components are compatible, which is vital, because not all parts of the operational LHC control system can be upgraded simultaneously. In addition, the Testbed can be used for performance and stress tests. Internally, the Testbed is driven by Atlassian Bamboo, a Continuous Integration server, which builds and deploys automatically new software versions into the Test...

  2. AMS San Diego Testbed - Calibration Data

    Data.gov (United States)

    Department of Transportation — The data in this repository were collected from the San Diego, California testbed, namely, I-15 from the interchange with SR-78 in the north to the interchange with...

  3. TARDEC Overview: Ground Vehicle Power and Mobility

    Science.gov (United States)

    2011-02-04

    Fuel & Water Distribution • Force Sustainment • Construction Equipment • Bridging • Assured Mobility Systems Robotics • TALON • PackBot • MARCbot...Equipment • Mechanical Countermine Equipment • Tactical Bridging Intelligent Ground Systems • Autonomous Robotics Systems • Safe Operations...Test Cell • Hybrid Electric Reconfigurable Moveable Integration Testbed (HERMIT) • Electro-chemical Analysis and Research Lab (EARL) • Battery Lab • Air

  4. High Precision Testbed to Evaluate Ethernet Performance for In-Car Networks

    DEFF Research Database (Denmark)

    Revsbech, Kasper; Madsen, Tatiana Kozlova; Schiøler, Henrik

    2012-01-01

    Validating safety-critical real-time systems such as in-car networks often involves a model-based performance analysis of the network. An important issue performing such analysis is to provide precise model parameters, matching the actual equipment. One way to obtain such parameters is to derive...... them by measurements of the equipment. In this work we describe the design of a testbed enabling active measurements on up to 1 [Gb=Sec] Copper based Ethernet Switches. By use of the testbed it self, we conduct a series of tests where the precision of the testbed is estimated. We find a maximum error...

  5. Development of a Remotely Operated Vehicle Test-bed

    Directory of Open Access Journals (Sweden)

    Biao WANG

    2013-06-01

    Full Text Available This paper presents the development of a remotely operated vehicle (ROV, designed to serve as a convenient, cost-effective platform for research and experimental validation of hardware, sensors and control algorithms. Both of the mechanical and control system design are introduced. The vehicle with a dimension 0.65 m long, 0.45 m wide has been designed to have a frame structure for modification of mounted devices and thruster allocation. For control system, STM32 based MCU boards specially designed for this project, are used as core processing boards. And an open source, modular, flexible software is developed. Experiment results demonstrate the effectiveness of the test-bed.

  6. Development of Liquid Propulsion Systems Testbed at MSFC

    Science.gov (United States)

    Alexander, Reginald; Nelson, Graham

    2016-01-01

    As NASA, the Department of Defense and the aerospace industry in general strive to develop capabilities to explore near-Earth, Cis-lunar and deep space, the need to create more cost effective techniques of propulsion system design, manufacturing and test is imperative in the current budget constrained environment. The physics of space exploration have not changed, but the manner in which systems are developed and certified needs to change if there is going to be any hope of designing and building the high performance liquid propulsion systems necessary to deliver crew and cargo to the further reaches of space. To further the objective of developing these systems, the Marshall Space Flight Center is currently in the process of formulating a Liquid Propulsion Systems testbed, which will enable rapid integration of components to be tested and assessed for performance in integrated systems. The manifestation of this testbed is a breadboard engine configuration (BBE) with facility support for consumables and/or other components as needed. The goal of the facility is to test NASA developed elements, but can be used to test articles developed by other government agencies, industry or academia. Joint government/private partnership is likely the approach that will be required to enable efficient propulsion system development. MSFC has recently tested its own additively manufactured liquid hydrogen pump, injector, and valves in a BBE hot firing. It is rapidly building toward testing the pump and a new CH4 injector in the BBE configuration to demonstrate a 22,000 lbf, pump-fed LO2/LCH4 engine for the Mars lander or in-space transportation. The value of having this BBE testbed is that as components are developed they may be easily integrated in the testbed and tested. MSFC is striving to enhance its liquid propulsion system development capability. Rapid design, analysis, build and test will be critical to fielding the next high thrust rocket engine. With the maturity of the

  7. Mounted Smartphones as Measurement and Control Platforms for Motor-Based Laboratory Test-Beds

    OpenAIRE

    Jared A. Frank; Anthony Brill; Vikram Kapila

    2016-01-01

    Laboratory education in science and engineering often entails the use of test-beds equipped with costly peripherals for sensing, acquisition, storage, processing, and control of physical behavior. However, costly peripherals are no longer necessary to obtain precise measurements and achieve stable feedback control of test-beds. With smartphones performing diverse sensing and processing tasks, this study examines the feasibility of mounting smartphones directly to test-beds to exploit their em...

  8. Wireless Sensor Networks TestBed: ASNTbed

    CSIR Research Space (South Africa)

    Dludla, AG

    2013-05-01

    Full Text Available Wireless sensor networks (WSNs) have been used in different types of applications and deployed within various environments. Simulation tools are essential for studying WSNs, especially for exploring large-scale networks. However, WSN testbeds...

  9. Growth plan for an inspirational test-bed of smart textile services

    NARCIS (Netherlands)

    Wensveen, S.A.G.; Tomico, O.; Bhomer, ten M.; Kuusk, K.

    2015-01-01

    In this pictorial we visualize the growth plan for an inspirational test-bed of smart textile product service systems. The goal of the test-bed is to inspire and inform the Dutch creative industries of textile, interaction and service design to combine their strengths and share opportunities. The

  10. Wireless Testbed Bonsai

    Science.gov (United States)

    2006-02-01

    wireless sensor device network, and a about 200 Stargate nodes higher-tier multi-hop peer- to-peer 802.11b wireless network. Leading up to the full ExScal...deployment, we conducted spatial scaling tests on our higher-tier protocols on a 7 × 7 grid of Stargates nodes 45m and with 90m separations respectively...onW and its scaled version W̃ . III. EXPERIMENTAL SETUP Description of Kansei testbed. A stargate is a single board linux-based computer [7]. It uses a

  11. Integrating Simulated Physics and Device Virtualization in Control System Testbeds

    OpenAIRE

    Redwood , Owen; Reynolds , Jason; Burmester , Mike

    2016-01-01

    Part 3: INFRASTRUCTURE MODELING AND SIMULATION; International audience; Malware and forensic analyses of embedded cyber-physical systems are tedious, manual processes that testbeds are commonly not designed to support. Additionally, attesting the physics impact of embedded cyber-physical system malware has no formal methodologies and is currently an art. This chapter describes a novel testbed design methodology that integrates virtualized embedded industrial control systems and physics simula...

  12. A Monocular Vision Measurement System of Three-Degree-of-Freedom Air-Bearing Test-Bed Based on FCCSP

    Science.gov (United States)

    Gao, Zhanyu; Gu, Yingying; Lv, Yaoyu; Xu, Zhenbang; Wu, Qingwen

    2018-06-01

    A monocular vision-based pose measurement system is provided for real-time measurement of a three-degree-of-freedom (3-DOF) air-bearing test-bed. Firstly, a circular plane cooperative target is designed. An image of a target fixed on the test-bed is then acquired. Blob analysis-based image processing is used to detect the object circles on the target. A fast algorithm (FCCSP) based on pixel statistics is proposed to extract the centers of object circles. Finally, pose measurements can be obtained when combined with the centers and the coordinate transformation relation. Experiments show that the proposed method is fast, accurate, and robust enough to satisfy the requirement of the pose measurement.

  13. Versatile Electric Propulsion Aircraft Testbed, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — An all-electric aircraft testbed is proposed to provide a dedicated development environment for the rigorous study and advancement of electrically powered aircraft....

  14. Comparison of two matrix data structures for advanced CSM testbed applications

    Science.gov (United States)

    Regelbrugge, M. E.; Brogan, F. A.; Nour-Omid, B.; Rankin, C. C.; Wright, M. A.

    1989-01-01

    The first section describes data storage schemes presently used by the Computational Structural Mechanics (CSM) testbed sparse matrix facilities and similar skyline (profile) matrix facilities. The second section contains a discussion of certain features required for the implementation of particular advanced CSM algorithms, and how these features might be incorporated into the data storage schemes described previously. The third section presents recommendations, based on the discussions of the prior sections, for directing future CSM testbed development to provide necessary matrix facilities for advanced algorithm implementation and use. The objective is to lend insight into the matrix structures discussed and to help explain the process of evaluating alternative matrix data structures and utilities for subsequent use in the CSM testbed.

  15. Holodeck Testbed Project

    Science.gov (United States)

    Arias, Adriel (Inventor)

    2016-01-01

    The main objective of the Holodeck Testbed is to create a cost effective, realistic, and highly immersive environment that can be used to train astronauts, carry out engineering analysis, develop procedures, and support various operations tasks. Currently, the Holodeck testbed allows to step into a simulated ISS (International Space Station) and interact with objects; as well as, perform Extra Vehicular Activities (EVA) on the surface of the Moon or Mars. The Holodeck Testbed is using the products being developed in the Hybrid Reality Lab (HRL). The HRL is combining technologies related to merging physical models with photo-realistic visuals to create a realistic and highly immersive environment. The lab also investigates technologies and concepts that are needed to allow it to be integrated with other testbeds; such as, the gravity offload capability provided by the Active Response Gravity Offload System (ARGOS). My main two duties were to develop and animate models for use in the HRL environments and work on a new way to interface with computers using Brain Computer Interface (BCI) technology. On my first task, I was able to create precise computer virtual tool models (accurate down to the thousandths or hundredths of an inch). To make these tools even more realistic, I produced animations for these tools so they would have the same mechanical features as the tools in real life. The computer models were also used to create 3D printed replicas that will be outfitted with tracking sensors. The sensor will allow the 3D printed models to align precisely with the computer models in the physical world and provide people with haptic/tactile feedback while wearing a VR (Virtual Reality) headset and interacting with the tools. Getting close to the end of my internship the lab bought a professional grade 3D Scanner. With this, I was able to replicate more intricate tools at a much more time-effective rate. The second task was to investigate the use of BCI to control

  16. Experimental Study and Modeling of Ground-Source Heat Pumps with Combi-Storage in Buildings

    Directory of Open Access Journals (Sweden)

    Wessam El-Baz

    2018-05-01

    Full Text Available There is a continuous growth of heat pump installations in residential buildings in Germany. The heat pumps are not only used for space heating and domestic hot water consumption but also to offer flexibility to the grid. The high coefficient of performance and the low cost of heat storages made the heat pumps one of the optimal candidates for the power to heat applications. Thus, several questions are raised about the optimal integration and control of heat pump system with buffer storages to maximize its operation efficiency and minimize the operation costs. In this paper, an experimental investigation is performed to study the performance of a ground source heat pump (GSHP with a combi-storage under several configurations and control factors. The experiments were performed on an innovative modular testbed that is capable of emulating a ground source to provide the heat pump with different temperature levels at different times of the day. Moreover, it can emulate the different building loads such as the space heating load and the domestic hot water consumption in real-time. The data gathered from the testbed and different experimental studies were used to develop a simulation model based on Modelica that can accurately simulate the dynamics of a GSHP in a building. The model was validated based on different metrics. Energetically, the difference between the developed model and the measured values was only 3% and 4% for the heat generation and electricity consumption, respectively.

  17. High-contrast imager for Complex Aperture Telescopes (HiCAT): testbed design and coronagraph developments

    Science.gov (United States)

    N'Diaye, Mamadou; Choquet, E.; Pueyo, L.; Elliot, E.; Perrin, M. D.; Wallace, J.; Anderson, R. E.; Carlotti, A.; Groff, T. D.; Hartig, G. F.; Kasdin, J.; Lajoie, C.; Levecq, O.; Long, C.; Macintosh, B.; Mawet, D.; Norman, C. A.; Shaklan, S.; Sheckells, M.; Sivaramakrishnan, A.; Soummer, R.

    2014-01-01

    We present a new high-contrast imaging testbed designed to provide complete solutions for wavefront sensing and control and starlight suppression with complex aperture telescopes (NASA APRA; Soummer PI). This includes geometries with central obstruction, support structures, and/or primary mirror segmentation. Complex aperture telescopes are often associated with large telescope designs, which are considered for future space missions. However, these designs makes high-contrast imaging challenging because of additional diffraction features in the point spread function. We present a novel optimization approach for the testbed optical and opto-mechanical design that minimizes the impact of both phase and amplitude errors from the wave propagation of testbed optics surface errors. This design approach allows us to define the specification for the bench optics, which we then compare to the manufactured parts. We discuss the testbed alignment and first results. We also present our coronagraph design for different testbed pupil shapes (AFTA or ATLAST), which involves a new method for the optimization of Apodized Pupil Lyot Coronagraphs (APLC).

  18. Aerospace Engineering Systems and the Advanced Design Technologies Testbed Experience

    Science.gov (United States)

    VanDalsem, William R.; Livingston, Mary E.; Melton, John E.; Torres, Francisco J.; Stremel, Paul M.

    1999-01-01

    Continuous improvement of aerospace product development processes is a driving requirement across much of the aerospace community. As up to 90% of the cost of an aerospace product is committed during the first 10% of the development cycle, there is a strong emphasis on capturing, creating, and communicating better information (both requirements and performance) early in the product development process. The community has responded by pursuing the development of computer-based systems designed to enhance the decision-making capabilities of product development individuals and teams. Recently, the historical foci on sharing the geometrical representation and on configuration management are being augmented: 1) Physics-based analysis tools for filling the design space database; 2) Distributed computational resources to reduce response time and cost; 3) Web-based technologies to relieve machine-dependence; and 4) Artificial intelligence technologies to accelerate processes and reduce process variability. The Advanced Design Technologies Testbed (ADTT) activity at NASA Ames Research Center was initiated to study the strengths and weaknesses of the technologies supporting each of these trends, as well as the overall impact of the combination of these trends on a product development event. Lessons learned and recommendations for future activities are reported.

  19. Use of Tabu Search in a Solver to Map Complex Networks onto Emulab Testbeds

    National Research Council Canada - National Science Library

    MacDonald, Jason E

    2007-01-01

    The University of Utah's solver for the testbed mapping problem uses a simulated annealing metaheuristic algorithm to map a researcher's experimental network topology onto available testbed resources...

  20. Event metadata records as a testbed for scalable data mining

    International Nuclear Information System (INIS)

    Gemmeren, P van; Malon, D

    2010-01-01

    At a data rate of 200 hertz, event metadata records ('TAGs,' in ATLAS parlance) provide fertile grounds for development and evaluation of tools for scalable data mining. It is easy, of course, to apply HEP-specific selection or classification rules to event records and to label such an exercise 'data mining,' but our interest is different. Advanced statistical methods and tools such as classification, association rule mining, and cluster analysis are common outside the high energy physics community. These tools can prove useful, not for discovery physics, but for learning about our data, our detector, and our software. A fixed and relatively simple schema makes TAG export to other storage technologies such as HDF5 straightforward. This simplifies the task of exploiting very-large-scale parallel platforms such as Argonne National Laboratory's BlueGene/P, currently the largest supercomputer in the world for open science, in the development of scalable tools for data mining. Using a domain-neutral scientific data format may also enable us to take advantage of existing data mining components from other communities. There is, further, a substantial literature on the topic of one-pass algorithms and stream mining techniques, and such tools may be inserted naturally at various points in the event data processing and distribution chain. This paper describes early experience with event metadata records from ATLAS simulation and commissioning as a testbed for scalable data mining tool development and evaluation.

  1. Development of a smart-antenna test-bed, demonstrating software defined digital beamforming

    NARCIS (Netherlands)

    Kluwer, T.; Slump, Cornelis H.; Schiphorst, Roelof; Hoeksema, F.W.

    2001-01-01

    This paper describes a smart-antenna test-bed consisting of ‘common of the shelf’ (COTS) hardware and software defined radio components. The use of software radio components enables a flexible platform to implement and test mobile communication systems as a real-world system. The test-bed is

  2. Closing the contrast gap between testbed and model prediction with WFIRST-CGI shaped pupil coronagraph

    Science.gov (United States)

    Zhou, Hanying; Nemati, Bijan; Krist, John; Cady, Eric; Prada, Camilo M.; Kern, Brian; Poberezhskiy, Ilya

    2016-07-01

    JPL has recently passed an important milestone in its technology development for a proposed NASA WFIRST mission coronagraph: demonstration of better than 1x10-8 contrast over broad bandwidth (10%) on both shaped pupil coronagraph (SPC) and hybrid Lyot coronagraph (HLC) testbeds with the WFIRST obscuration pattern. Challenges remain, however, in the technology readiness for the proposed mission. One is the discrepancies between the achieved contrasts on the testbeds and their corresponding model predictions. A series of testbed diagnoses and modeling activities were planned and carried out on the SPC testbed in order to close the gap. A very useful tool we developed was a derived "measured" testbed wavefront control Jacobian matrix that could be compared with the model-predicted "control" version that was used to generate the high contrast dark hole region in the image plane. The difference between these two is an estimate of the error in the control Jacobian. When the control matrix, which includes both amplitude and phase, was modified to reproduce the error, the simulated performance closely matched the SPC testbed behavior in both contrast floor and contrast convergence speed. This is a step closer toward model validation for high contrast coronagraphs. Further Jacobian analysis and modeling provided clues to the possible sources for the mismatch: DM misregistration and testbed optical wavefront error (WFE) and the deformable mirror (DM) setting for correcting this WFE. These analyses suggested that a high contrast coronagraph has a tight tolerance in the accuracy of its control Jacobian. Modifications to both testbed control model as well as prediction model are being implemented, and future works are discussed.

  3. Definition study for variable cycle engine testbed engine and associated test program

    Science.gov (United States)

    Vdoviak, J. W.

    1978-01-01

    The product/study double bypass variable cycle engine (VCE) was updated to incorporate recent improvements. The effect of these improvements on mission range and noise levels was determined. This engine design was then compared with current existing high-technology core engines in order to define a subscale testbed configuration that simulated many of the critical technology features of the product/study VCE. Detailed preliminary program plans were then developed for the design, fabrication, and static test of the selected testbed engine configuration. These plans included estimated costs and schedules for the detail design, fabrication and test of the testbed engine and the definition of a test program, test plan, schedule, instrumentation, and test stand requirements.

  4. University of Florida Advanced Technologies Campus Testbed

    Science.gov (United States)

    2017-09-21

    The University of Florida (UF) and its Transportation Institute (UFTI), the Florida Department of Transportation (FDOT) and the City of Gainesville (CoG) are cooperating to develop a smart transportation testbed on the University of Florida (UF) main...

  5. The OGC Innovation Program Testbeds - Advancing Architectures for Earth and Systems

    Science.gov (United States)

    Bermudez, L. E.; Percivall, G.; Simonis, I.; Serich, S.

    2017-12-01

    The OGC Innovation Program provides a collaborative agile process for solving challenging science problems and advancing new technologies. Since 1999, 100 initiatives have taken place, from multi-million dollar testbeds to small interoperability experiments. During these initiatives, sponsors and technology implementers (including academia and private sector) come together to solve problems, produce prototypes, develop demonstrations, provide best practices, and advance the future of standards. This presentation will provide the latest system architectures that can be used for Earth and space systems as a result of the OGC Testbed 13, including the following components: Elastic cloud autoscaler for Earth Observations (EO) using a WPS in an ESGF hybrid climate data research platform. Accessibility of climate data for the scientist and non-scientist users via on demand models wrapped in WPS. Standards descriptions for containerize applications to discover processes on the cloud, including using linked data, a WPS extension for hybrid clouds and linking to hybrid big data stores. OpenID and OAuth to secure OGC Services with built-in Attribute Based Access Control (ABAC) infrastructures leveraging GeoDRM patterns. Publishing and access of vector tiles, including use of compression and attribute options reusing patterns from WMS, WMTS and WFS. Servers providing 3D Tiles and streaming of data, including Indexed 3d Scene Layer (I3S), CityGML and Common DataBase (CDB). Asynchronous Services with advanced pushed notifications strategies, with a filter language instead of simple topic subscriptions, that can be use across OGC services. Testbed 14 will continue advancing topics like Big Data, security, and streaming, as well as making easier to use OGC services (e.g. RESTful APIs). The Call for Participation will be issued in December and responses are due on mid January 2018.

  6. Context-aware local Intrusion Detection in SCADA systems : a testbed and two showcases

    NARCIS (Netherlands)

    Chromik, Justyna Joanna; Haverkort, Boudewijn R.H.M.; Remke, Anne Katharina Ingrid; Pilch, Carina; Brackmann, Pascal; Duhme, Christof; Everinghoff, Franziska; Giberlein, Artur; Teodorowicz, Thomas; Wieland, Julian

    2017-01-01

    This paper illustrates the use of a testbed that we have developed for context-aware local intrusion detection. This testbed is based on the co-simulation framework Mosaik and allows for the validation of local intrusion detection mechanisms at field stations in power distribution networks. For two

  7. Spacelab operations planning. [ground handling, launch, flight and experiments

    Science.gov (United States)

    Lee, T. J.

    1976-01-01

    The paper reviews NASA planning in the fields of ground, launch and flight operations and experiment integration to effectively operate Spacelab. Payload mission planning is discussed taking consideration of orbital analysis and the mission of a multiuser payload which may be either single or multidiscipline. Payload analytical integration - as active process of analyses to ensure that the experiment payload is compatible to the mission objectives and profile ground and flight operations and that the resource demands upon Spacelab can be satisfied - is considered. Software integration is touched upon and the major integration levels in ground operational processing of Spacelab and its experimental payloads are examined. Flight operations, encompassing the operation of the Space Transportation System and the payload, are discussed as are the initial Spacelab missions. Charts and diagrams are presented illustrating the various planning areas.

  8. Design and Development of a 200-kW Turbo-Electric Distributed Propulsion Testbed

    Science.gov (United States)

    Papathakis, Kurt V.; Kloesel, Kurt J.; Lin, Yohan; Clarke, Sean; Ediger, Jacob J.; Ginn, Starr

    2016-01-01

    The National Aeronautics and Space Administration (NASA) Armstrong Flight Research Center (AFRC) (Edwards, California) is developing a Hybrid-Electric Integrated Systems Testbed (HEIST) Testbed as part of the HEIST Project, to study power management and transition complexities, modular architectures, and flight control laws for turbo-electric distributed propulsion technologies using representative hardware and piloted simulations. Capabilities are being developed to assess the flight readiness of hybrid electric and distributed electric vehicle architectures. Additionally, NASA will leverage experience gained and assets developed from HEIST to assist in flight-test proposal development, flight-test vehicle design, and evaluation of hybrid electric and distributed electric concept vehicles for flight safety. The HEIST test equipment will include three trailers supporting a distributed electric propulsion wing, a battery system and turbogenerator, dynamometers, and supporting power and communication infrastructure, all connected to the AFRC Core simulation. Plans call for 18 high performance electric motors that will be powered by batteries and the turbogenerator, and commanded by a piloted simulation. Flight control algorithms will be developed on the turbo-electric distributed propulsion system.

  9. Cooperative Search with Autonomous Vehicles in a 3D Aquatic Testbed

    Science.gov (United States)

    2012-01-01

    Cooperative Search with Autonomous Vehicles in a 3D Aquatic Testbed Matthew Keeter1, Daniel Moore2,3, Ryan Muller2,3, Eric Nieters1, Jennifer...Many applications for autonomous vehicles involve three-dimensional domains, notably aerial and aquatic environments. Such applications include mon...TYPE 3. DATES COVERED 00-00-2012 to 00-00-2012 4. TITLE AND SUBTITLE Cooperative Search With Autonomous Vehicles In A 3D Aquatic Testbed 5a

  10. PEER Testbed Study on a Laboratory Building: Exercising Seismic Performance Assessment

    OpenAIRE

    Comerio, Mary C.; Stallmeyer, John C.; Smith, Ryan; Makris, Nicos; Konstantinidis, Dimitrios; Mosalam, Khalid; Lee, Tae-Hyung; Beck, James L.; Porter, Keith A.; Shaikhutdinov, Rustem; Hutchinson, Tara; Chaudhuri, Samit Ray; Chang, Stephanie E.; Falit-Baiamonte, Anthony; Holmes, William T.

    2005-01-01

    From 2002 to 2004 (years five and six of a ten-year funding cycle), the PEER Center organized the majority of its research around six testbeds. Two buildings and two bridges, a campus, and a transportation network were selected as case studies to “exercise” the PEER performance-based earthquake engineering methodology. All projects involved interdisciplinary teams of researchers, each producing data to be used by other colleagues in their research. The testbeds demonstrat...

  11. Modular Algorithm Testbed Suite (MATS): A Software Framework for Automatic Target Recognition

    Science.gov (United States)

    2017-01-01

    NAVAL SURFACE WARFARE CENTER PANAMA CITY DIVISION PANAMA CITY, FL 32407-7001 TECHNICAL REPORT NSWC PCD TR-2017-004 MODULAR ...31-01-2017 Technical Modular Algorithm Testbed Suite (MATS): A Software Framework for Automatic Target Recognition DR...flexible platform to facilitate the development and testing of ATR algorithms. To that end, NSWC PCD has created the Modular Algorithm Testbed Suite

  12. Easy as Pi: A Network Coding Raspberry Pi Testbed

    Directory of Open Access Journals (Sweden)

    Chres W. Sørensen

    2016-10-01

    Full Text Available In the near future, upcoming communications and storage networks are expected to tolerate major difficulties produced by huge amounts of data being generated from the Internet of Things (IoT. For these types of networks, strategies and mechanisms based on network coding have appeared as an alternative to overcome these difficulties in a holistic manner, e.g., without sacrificing the benefit of a given network metric when improving another. There has been recurrent issues on: (i making large-scale deployments akin to the Internet of Things; (ii assessing and (iii replicating the obtained results in preliminary studies. Therefore, finding testbeds that can deal with large-scale deployments and not lose historic data in order to evaluate these mechanisms are greatly needed and desirable from a research perspective. However, this can be hard to manage, not only due to the inherent costs of the hardware, but also due to maintenance challenges. In this paper, we present the required key steps to design, setup and maintain an inexpensive testbed using Raspberry Pi devices for communications and storage networks with network coding capabilities. This testbed can be utilized for any applications requiring results replicability.

  13. The Living With a Star Space Environment Testbed Program

    Science.gov (United States)

    Barth, Janet; LaBel, Kenneth; Day, John H. (Technical Monitor)

    2001-01-01

    NASA has initiated the Living with a Star (LWS) Program to develop the scientific understanding to address the aspects of the Connected Sun-Earth system that affects life and society. The Program Architecture includes science missions, theory and modeling and Space Environment Testbeds (SET). This current paper discusses the Space Environment Testbeds. The goal of the SET program is to improve the engineering approach to accomodate and/or mitigate the effects of solar variability on spacecraft design and operations. The SET Program will infuse new technologies into the space programs through collection of data in space and subsequent design and validation of technologies. Examples of these technologies are cited and discussed.

  14. Carrier Plus: A sensor payload for Living With a Star Space Environment Testbed (LWS/SET)

    Science.gov (United States)

    Marshall, Cheryl J.; Moss, Steven; Howard, Regan; LaBel, Kenneth A.; Grycewicz, Tom; Barth, Janet L.; Brewer, Dana

    2003-01-01

    The Defense Threat Reduction Agency (DTR4) and National Aeronautics and Space Administration (NASA) Goddard Space Flight Center are collaborating to develop the Carrier Plus sensor experiment platform as a capability of the Space Environments Testbed (SET). The Space Environment Testbed (SET) provides flight opportunities for technology experiments as part of NASA's Living With a Star (LWS) program. The Carrier Plus will provide new capability to characterize sensor technologies such as state-of-the-art visible focal plane arrays (FPAs) in a natural space radiation environment. The technical objectives include on-orbit validation of recently developed FPA technologies and performance prediction methodologies, as well as characterization of the FPA radiation response to total ionizing dose damage, displacement damage and transients. It is expected that the sensor experiment will carry 4-6 FPAs and associated radiation correlative environment monitors (CEMs) for a 2006-2007 launch. Sensor technology candidates may include n- and p-charge coupled devices (CCDs), active pixel sensors (APS), and hybrid CMOS arrays. The presentation will describe the Carrier Plus goals and objectives, as well as provide details about the architecture and design. More information on the LWS program can be found at http://lws.gsfc.nasa.gov/. Business announcements for LWS/SET and program briefings are posted at http://lws-set.gsfc.nasa.gov

  15. Graphical interface between the CIRSSE testbed and CimStation software with MCS/CTOS

    Science.gov (United States)

    Hron, Anna B.

    1992-01-01

    This research is concerned with developing a graphical simulation of the testbed at the Center for Intelligent Robotic Systems for Space Exploration (CIRSSE) and the interface which allows for communication between the two. Such an interface is useful in telerobotic operations, and as a functional interaction tool for testbed users. Creating a simulated model of a real world system, generates inevitable calibration discrepancies between them. This thesis gives a brief overview of the work done to date in the area of workcell representation and communication, describes the development of the CIRSSE interface, and gives a direction for future work in the area of system calibration. The CimStation software used for development of this interface, is a highly versatile robotic workcell simulation package which has been programmed for this application with a scale graphical model of the testbed, and supporting interface menu code. A need for this tool has been identified for the reasons of path previewing, as a window on teleoperation and for calibration of simulated vs. real world models. The interface allows information (i.e., joint angles) generated by CimStation to be sent as motion goal positions to the testbed robots. An option of the interface has been established such that joint angle information generated by supporting testbed algorithms (i.e., TG, collision avoidance) can be piped through CimStation as a visual preview of the path.

  16. Implementation of a virtual link between power system testbeds at Marshall Spaceflight Center and Lewis Research Center

    Science.gov (United States)

    Doreswamy, Rajiv

    1990-01-01

    The Marshall Space Flight Center (MSFC) owns and operates a space station module power management and distribution (SSM-PMAD) testbed. This system, managed by expert systems, is used to analyze and develop power system automation techniques for Space Station Freedom. The Lewis Research Center (LeRC), Cleveland, Ohio, has developed and implemented a space station electrical power system (EPS) testbed. This system and its power management controller are representative of the overall Space Station Freedom power system. A virtual link is being implemented between the testbeds at MSFC and LeRC. This link would enable configuration of SSM-PMAD as a load center for the EPS testbed at LeRC. This connection will add to the versatility of both systems, and provide an environment of enhanced realism for operation of both testbeds.

  17. Cognitive Medical Wireless Testbed System (COMWITS)

    Science.gov (United States)

    2016-11-01

    Number: ...... ...... Sub Contractors (DD882) Names of other research staff Inventions (DD882) Scientific Progress This testbed merges two ARO grants...bit 64 bit CPU Intel Xeon Processor E5-1650v3 (6C, 3.5 GHz, Turbo, HT , 15M, 140W) Intel Core i7-3770 (3.4 GHz Quad Core, 77W) Dual Intel Xeon

  18. Aerodynamic design of the National Rotor Testbed.

    Energy Technology Data Exchange (ETDEWEB)

    Kelley, Christopher Lee [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-10-01

    A new wind turbine blade has been designed for the National Rotor Testbed (NRT) project and for future experiments at the Scaled Wind Farm Technology (SWiFT) facility with a specific focus on scaled wakes. This report shows the aerodynamic design of new blades that can produce a wake that has similitude to utility scale blades despite the difference in size and location in the atmospheric boundary layer. Dimensionless quantities circulation, induction, thrust coefficient, and tip-speed-ratio were kept equal between rotor scales in region 2 of operation. The new NRT design matched the aerodynamic quantities of the most common wind turbine in the United States, the GE 1.5sle turbine with 37c model blades. The NRT blade design is presented along with its performance subject to the winds at SWiFT. The design requirements determined by the SWiFT experimental test campaign are shown to be met.

  19. A Method to Analyze Threats and Vulnerabilities by Using a Cyber Security Test-bed of an Operating NPP

    International Nuclear Information System (INIS)

    Kim, Yong Sik; Son, Choul Woong; Lee, Soo Ill

    2016-01-01

    In order to implement cyber security controls for an Operating NPP, a security assessment should conduct in advance, and it is essential to analyze threats and vulnerabilities for a cyber security risk assessment phase. It might be impossible to perform a penetration test or scanning for a vulnerability analysis because the test may cause adverse effects on the inherent functions of ones. This is the reason why we develop and construct a cyber security test-bed instead of using real I and C systems in the operating NPP. In this paper, we propose a method to analyze threats and vulnerabilities of a specific target system by using a cyber security test-bed. The test-bed is being developed considering essential functions of the selected safety and non-safety system. This paper shows the method to analyze threats and vulnerabilities of a specific target system by using a cyber security test-bed. In order to develop the cyber security test-bed with both safety and non-safety functions, test-bed functions analysis and preliminary threats and vulnerabilities identification have been conducted. We will determine the attack scenarios and conduct the test-bed based vulnerability analysis

  20. A Method to Analyze Threats and Vulnerabilities by Using a Cyber Security Test-bed of an Operating NPP

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yong Sik; Son, Choul Woong; Lee, Soo Ill [KHNP CRI, Daejeon (Korea, Republic of)

    2016-10-15

    In order to implement cyber security controls for an Operating NPP, a security assessment should conduct in advance, and it is essential to analyze threats and vulnerabilities for a cyber security risk assessment phase. It might be impossible to perform a penetration test or scanning for a vulnerability analysis because the test may cause adverse effects on the inherent functions of ones. This is the reason why we develop and construct a cyber security test-bed instead of using real I and C systems in the operating NPP. In this paper, we propose a method to analyze threats and vulnerabilities of a specific target system by using a cyber security test-bed. The test-bed is being developed considering essential functions of the selected safety and non-safety system. This paper shows the method to analyze threats and vulnerabilities of a specific target system by using a cyber security test-bed. In order to develop the cyber security test-bed with both safety and non-safety functions, test-bed functions analysis and preliminary threats and vulnerabilities identification have been conducted. We will determine the attack scenarios and conduct the test-bed based vulnerability analysis.

  1. Vacuum Nuller Testbed (VNT) Performance, Characterization and Null Control: Progress Report

    Science.gov (United States)

    Lyon, Richard G.; Clampin, Mark; Petrone, Peter; Mallik, Udayan; Madison, Timothy; Bolcar, Matthew R.; Noecker, M. Charley; Kendrick, Stephen; Helmbrecht, Michael

    2011-01-01

    Herein we report on the development. sensing and control and our first results with the Vacuum Nuller Testbed to realize a Visible Nulling Coronagraph (VNC) for exoplanet coronagraphy. The VNC is one of the few approaches that works with filled. segmented and sparse or diluted-aperture telescope systems. It thus spans a range of potential future NASA telescopes and could be Hown as a separate instrument on such a future mission. NASA/Goddard Space Flight Center (GSFC) has a well-established effort to develop VNC technologies. and has developed an incremental sequence of VNC testbeds to advance this approach and the enabling technologies associated with it. We discuss the continued development of the vacuum Visible Nulling Coronagraph testbed (VNT). Tbe VNT is an ultra-stable vibration isolated testbed that operates under closed-loop control within a vacuum chamber. It will be used to achieve an incremental sequence of three visible-light nulling milestones with sequentially higher contrasts of 10(sup 8), 10(sup 9) and ideally 10(sup 10) at an inner working angle of 2*lambda/D. The VNT is based on a modified Mach-Zehnder nulling interferometer, with a "W" configuration to accommodate a hex-packed MEMS based deformable mirror, a coherent fiber bundle and achromatic phase shifters. We discuss the initial laboratory results, the optical configuration, critical technologies and the null sensing and control approach.

  2. Vacuum nuller testbed (VNT) performance, characterization and null control: progress report

    Science.gov (United States)

    Lyon, Richard G.; Clampin, Mark; Petrone, Peter; Mallik, Udayan; Madison, Timothy; Bolcar, Matthew R.; Noecker, M. Charley; Kendrick, Stephen; Helmbrecht, Michael

    2011-10-01

    Herein we report on the development, sensing and control and our first results with the Vacuum Nuller Testbed to realize a Visible Nulling Coronagraph (VNC) for exoplanet coronagraphy. The VNC is one of the few approaches that works with filled, segmented and sparse or diluted-aperture telescope systems. It thus spans a range of potential future NASA telescopes and could be flown as a separate instrument on such a future mission. NASA/Goddard Space Flight Center (GSFC) has a well-established effort to develop VNC technologies, and has developed an incremental sequence of VNC testbeds to advance this approach and the enabling technologies associated with it. We discuss the continued development of the vacuum Visible Nulling Coronagraph testbed (VNT). The VNT is an ultra-stable vibration isolated testbed that operates under closed-loop control within a vacuum chamber. It will be used to achieve an incremental sequence of three visible-light nulling milestones with sequentially higher contrasts of 108, 109, and ideally 1010 at an inner working angle of 2*λ/D. The VNT is based on a modified Mach-Zehnder nulling interferometer, with a "W" configuration to accommodate a hex-packed MEMS based deformable mirror, a coherent fiber bundle and achromatic phase shifters. We discuss the initial laboratory results, the optical configuration, critical technologies and the null sensing and control approach.

  3. Remembering and knowing personality traits: figure/ground asymmetries in person-related retrieval experience.

    Science.gov (United States)

    Wehr, Thomas

    2008-01-01

    In two experiments, the effect of category salience on retrieval experience was investigated. In Experiment 1, participants rated typicality or concreteness of personality traits that differed in stereotype reference (i.e., consistent, inconsistent, and neutral in relation to the age stereotype). More remember judgments were given for consistent and inconsistent traits in contrast to neutral traits, thereby indicating a figure/ground asymmetry. In Experiment 2, neutral traits were excluded and a classical figure/ground phenomenon was demonstrated for the retrieval experience of traits (i.e., reversibility of an ambiguous figure after typicality and untypicality ratings). Altogether, the results suggest that metacognitive trait representations depend on principles of figure/ground asymmetries rather than on functional principles of social information processing.

  4. The Soil Moisture Active Passive Mission (SMAP) Science Data Products: Results of Testing with Field Experiment and Algorithm Testbed Simulation Environment Data

    Science.gov (United States)

    Entekhabi, Dara; Njoku, Eni E.; O'Neill, Peggy E.; Kellogg, Kent H.; Entin, Jared K.

    2010-01-01

    Talk outline 1. Derivation of SMAP basic and applied science requirements from the NRC Earth Science Decadal Survey applications 2. Data products and latencies 3. Algorithm highlights 4. SMAP Algorithm Testbed 5. SMAP Working Groups and community engagement

  5. Visible nulling coronagraphy testbed development for exoplanet detection

    Science.gov (United States)

    Lyon, Richard G.; Clampin, Mark; Woodruff, Robert A.; Vasudevan, Gopal; Thompson, Patrick; Chen, Andrew; Petrone, Peter; Booth, Andrew; Madison, Timothy; Bolcar, Matthew; Noecker, M. Charley; Kendrick, Stephen; Melnick, Gary; Tolls, Volker

    2010-07-01

    Three of the recently completed NASA Astrophysics Strategic Mission Concept (ASMC) studies addressed the feasibility of using a Visible Nulling Coronagraph (VNC) as the prime instrument for exoplanet science. The VNC approach is one of the few approaches that works with filled, segmented and sparse or diluted aperture telescope systems and thus spans the space of potential ASMC exoplanet missions. NASA/Goddard Space Flight Center (GSFC) has a well-established effort to develop VNC technologies and has developed an incremental sequence of VNC testbeds to advance the this approach and the technologies associated with it. Herein we report on the continued development of the vacuum Visible Nulling Coronagraph testbed (VNT). The VNT is an ultra-stable vibration isolated testbed that operates under high bandwidth closed-loop control within a vacuum chamber. It will be used to achieve an incremental sequence of three visible light nulling milestones of sequentially higher contrasts of 108, 109 and 1010 at an inner working angle of 2*λ/D and ultimately culminate in spectrally broadband (>20%) high contrast imaging. Each of the milestones, one per year, is traceable to one or more of the ASMC studies. The VNT uses a modified Mach-Zehnder nulling interferometer, modified with a modified "W" configuration to accommodate a hex-packed MEMS based deformable mirror, a coherent fiber bundle and achromatic phase shifters. Discussed will be the optical configuration laboratory results, critical technologies and the null sensing and control approach.

  6. Analysis, Modeling, and Simulation (AMS) Testbed Development and Evaluation to Support Dynamic Mobility Applications (DMA) and Active Transportation and Demand Management (ATDM) Programs - calibration Report for Phoenix Testbed : Final Report. [supporting datasets - Phoenix Testbed

    Science.gov (United States)

    2017-07-26

    The datasets in this zip file are in support of FHWA-JPO-16-379, Analysis, Modeling, and Simulation (AMS) Testbed Development and Evaluation to Support Dynamic Mobility Applications (DMA) and Active Transportation and Demand Management (ATDM) Program...

  7. Space Shuttle Boundary Layer Transition Flight Experiment Ground Testing Overview

    Science.gov (United States)

    Berger, Karen T.; Anderson, Brian P.; Campbell, Charles H.

    2014-01-01

    In support of the Boundary Layer Transition (BLT) Flight Experiment (FE) Project in which a manufactured protuberance tile was installed on the port wing of Space Shuttle Orbiter Discovery for STS-119, STS- 128, STS-131 and STS-133 as well as Space Shuttle Orbiter Endeavour for STS-134, a significant ground test campaign was completed. The primary goals of the test campaign were to provide ground test data to support the planning and safety certification efforts required to fly the flight experiment as well as validation for the collected flight data. These test included Arcjet testing of the tile protuberance, aerothermal testing to determine the boundary layer transition behavior and resultant surface heating and planar laser induced fluorescence (PLIF) testing in order to gain a better understanding of the flow field characteristics associated with the flight experiment. This paper provides an overview of the BLT FE Project ground testing. High-level overviews of the facilities, models, test techniques and data are presented, along with a summary of the insights gained from each test.

  8. Full-Scaled Advanced Systems Testbed: Ensuring Success of Adaptive Control Research Through Project Lifecycle Risk Mitigation

    Science.gov (United States)

    Pavlock, Kate M.

    2011-01-01

    The National Aeronautics and Space Administration's Dryden Flight Research Center completed flight testing of adaptive controls research on the Full-Scale Advance Systems Testbed (FAST) in January of 2011. The research addressed technical challenges involved with reducing risk in an increasingly complex and dynamic national airspace. Specific challenges lie with the development of validated, multidisciplinary, integrated aircraft control design tools and techniques to enable safe flight in the presence of adverse conditions such as structural damage, control surface failures, or aerodynamic upsets. The testbed is an F-18 aircraft serving as a full-scale vehicle to test and validate adaptive flight control research and lends a significant confidence to the development, maturation, and acceptance process of incorporating adaptive control laws into follow-on research and the operational environment. The experimental systems integrated into FAST were designed to allow for flexible yet safe flight test evaluation and validation of modern adaptive control technologies and revolve around two major hardware upgrades: the modification of Production Support Flight Control Computers (PSFCC) and integration of two, fourth-generation Airborne Research Test Systems (ARTS). Post-hardware integration verification and validation provided the foundation for safe flight test of Nonlinear Dynamic Inversion and Model Reference Aircraft Control adaptive control law experiments. To ensure success of flight in terms of cost, schedule, and test results, emphasis on risk management was incorporated into early stages of design and flight test planning and continued through the execution of each flight test mission. Specific consideration was made to incorporate safety features within the hardware and software to alleviate user demands as well as into test processes and training to reduce human factor impacts to safe and successful flight test. This paper describes the research configuration

  9. Prognostics-Enabled Power Supply for ADAPT Testbed, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Ridgetop's role is to develop electronic prognostics for sensing power systems in support of NASA/Ames ADAPT testbed. The prognostic enabled power systems from...

  10. Towards a Perpetual Sensor Network Testbed without Backchannel

    DEFF Research Database (Denmark)

    Johansen, Aslak; Bonnet, Philippe; Sørensen, Thomas

    2012-01-01

    The sensor network testbeds available today rely on a communication channel different from the mote radio - a backchannel - to facilitate mote reprogramming, health monitoring and performance analysis. Such backchannels are either supported as wired communication channels (USB or Ethernet), or vi...

  11. Simulation and experiment on the thermal performance of U-vertical ground coupled heat exchanger

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xinguo; Chen, Zhihao; Zhao, Jun [Department of Thermal Engineering, School of Mechanical Engineering, Tianjin University, Tianjin 300072 (China)

    2006-10-15

    This paper presented both the numerical simulations and experiments on the thermal performance of U-vertical ground coupled heat exchanger (UGCHE). The variation of the ground temperature and heat balance of the system were analyzed and compared in different operation modes in the numerical simulation. Experiments on the operation performance of the ground-coupled heat pump (GCHP) with the UGCHE were carried out. It shows that the ground source can be used as the heat source/sink for GCHP systems to have higher efficiency in saving energy. To preserve the ground resource for the sustainable utilization as heat source/sink, the heat emitted to ground and heat extracted from ground should be balanced. (author)

  12. Adaptive optics correction into single mode fiber for a low Earth orbiting space to ground optical communication link using the OPALS downlink.

    Science.gov (United States)

    Wright, Malcolm W; Morris, Jeffery F; Kovalik, Joseph M; Andrews, Kenneth S; Abrahamson, Matthew J; Biswas, Abhijit

    2015-12-28

    An adaptive optics (AO) testbed was integrated to the Optical PAyload for Lasercomm Science (OPALS) ground station telescope at the Optical Communications Telescope Laboratory (OCTL) as part of the free space laser communications experiment with the flight system on board the International Space Station (ISS). Atmospheric turbulence induced aberrations on the optical downlink were adaptively corrected during an overflight of the ISS so that the transmitted laser signal could be efficiently coupled into a single mode fiber continuously. A stable output Strehl ratio of around 0.6 was demonstrated along with the recovery of a 50 Mbps encoded high definition (HD) video transmission from the ISS at the output of the single mode fiber. This proof of concept demonstration validates multi-Gbps optical downlinks from fast slewing low-Earth orbiting (LEO) spacecraft to ground assets in a manner that potentially allows seamless space to ground connectivity for future high data-rates network.

  13. High Contrast Vacuum Nuller Testbed (VNT) Contrast, Performance and Null Control

    Science.gov (United States)

    Lyon, Richard G.; Clampin, Mark; Petrone, Peter; Mallik, Udayan; Madison, Timothy; Bolcar, Matthew R.

    2012-01-01

    Herein we report on our Visible Nulling Coronagraph high-contrast result of 109 contrast averaged over a focal planeregion extending from 14 D with the Vacuum Nuller Testbed (VNT) in a vibration isolated vacuum chamber. TheVNC is a hybrid interferometriccoronagraphic approach for exoplanet science. It operates with high Lyot stopefficiency for filled, segmented and sparse or diluted-aperture telescopes, thereby spanning the range of potential futureNASA flight telescopes. NASAGoddard Space Flight Center (GSFC) has a well-established effort to develop the VNCand its technologies, and has developed an incremental sequence of VNC testbeds to advance this approach and itsenabling technologies. These testbeds have enabled advancement of high-contrast, visible light, nulling interferometry tounprecedented levels. The VNC is based on a modified Mach-Zehnder nulling interferometer, with a W configurationto accommodate a hex-packed MEMS based deformable mirror, a coherent fiber bundle and achromatic phase shifters.We give an overview of the VNT and discuss the high-contrast laboratory results, the optical configuration, criticaltechnologies and null sensing and control.

  14. High contrast vacuum nuller testbed (VNT) contrast, performance, and null control

    Science.gov (United States)

    Lyon, Richard G.; Clampin, Mark; Petrone, Peter; Mallik, Udayan; Madison, Timothy; Bolcar, Matthew R.

    2012-09-01

    Herein we report on our Visible Nulling Coronagraph high-contrast result of 109 contrast averaged over a focal plane region extending from 1 - 4 λ/D with the Vacuum Nuller Testbed (VNT) in a vibration isolated vacuum chamber. The VNC is a hybrid interferometric/coronagraphic approach for exoplanet science. It operates with high Lyot stop efficiency for filled, segmented and sparse or diluted-aperture telescopes, thereby spanning the range of potential future NASA flight telescopes. NASA/Goddard Space Flight Center (GSFC) has a well-established effort to develop the VNC and its technologies, and has developed an incremental sequence of VNC testbeds to advance this approach and its enabling technologies. These testbeds have enabled advancement of high-contrast, visible light, nulling interferometry to unprecedented levels. The VNC is based on a modified Mach-Zehnder nulling interferometer, with a “W” configuration to accommodate a hex-packed MEMS based deformable mirror, a coherent fiber bundle and achromatic phase shifters. We give an overview of the VNT and discuss the high-contrast laboratory results, the optical configuration, critical technologies and null sensing and control.

  15. Open-Source Based Testbed for Multioperator 4G/5G Infrastructure Sharing in Virtual Environments

    Directory of Open Access Journals (Sweden)

    Ricardo Marco Alaez

    2017-01-01

    Full Text Available Fourth-Generation (4G mobile networks are based on Long-Term Evolution (LTE technologies and are being deployed worldwide, while research on further evolution towards the Fifth Generation (5G has been recently initiated. 5G will be featured with advanced network infrastructure sharing capabilities among different operators. Therefore, an open-source implementation of 4G/5G networks with this capability is crucial to enable early research in this area. The main contribution of this paper is the design and implementation of such a 4G/5G open-source testbed to investigate multioperator infrastructure sharing capabilities executed in virtual architectures. The proposed design and implementation enable the virtualization and sharing of some of the components of the LTE architecture. A testbed has been implemented and validated with intensive empirical experiments conducted to validate the suitability of virtualizing LTE components in virtual infrastructures (i.e., infrastructures with multitenancy sharing capabilities. The impact of the proposed technologies can lead to significant saving of both capital and operational costs for mobile telecommunication operators.

  16. Implementation of a RPS Cyber Security Test-bed with Two PLCs

    International Nuclear Information System (INIS)

    Shin, Jinsoo; Heo, Gyunyoung; Son, Hanseong; An, Yongkyu; Rizwan, Uddin

    2015-01-01

    Our research team proposed the methodology to evaluate cyber security with Bayesian network (BN) as a cyber security evaluation model and help operator, licensee, licensor or regulator in granting evaluation priorities. The methodology allowed for overall evaluation of cyber security by considering architectural aspect of facility and management aspect of cyber security at the same time. In order to emphasize reality of this model by inserting true data, it is necessary to conduct a penetration test that pretends an actual cyber-attack. Through the collaboration with University of Illinois at Urbana-Champaign, which possesses the Tricon a safety programmable logic controller (PLC) used at nuclear power plants and develops a test-bed for nuclear power plant, a test-bed for reactor protection system (RPS) is being developed with the PLCs. Two PLCs are used to construct a simple test-bed for RPS, bi-stable processor (BP) and coincidence processor (CP). By using two PLCs, it is possible to examine cyber-attack against devices such as PLC, cyber-attack against communication between devices, and the effects of a PLC on the other PLC. Two PLCs were used to construct a test-bed for penetration test in this study. Advantages of using two or more PLCs instead of single PLC are as follows. 1) Results of cyber-attack reflecting characteristics among PLCs can be obtained. 2) Cyber-attack can be attempted using a method of attacking communication between PLCs. True data obtained can be applied to existing cyber security evaluation model to emphasize reality of the model

  17. Implementation of a RPS Cyber Security Test-bed with Two PLCs

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Jinsoo; Heo, Gyunyoung [Kyung Hee Univ., Yongin (Korea, Republic of); Son, Hanseong [Joongbu Univ., Geumsan (Korea, Republic of); An, Yongkyu; Rizwan, Uddin [University of Illinois at Urbana-Champaign, Urbana (United States)

    2015-10-15

    Our research team proposed the methodology to evaluate cyber security with Bayesian network (BN) as a cyber security evaluation model and help operator, licensee, licensor or regulator in granting evaluation priorities. The methodology allowed for overall evaluation of cyber security by considering architectural aspect of facility and management aspect of cyber security at the same time. In order to emphasize reality of this model by inserting true data, it is necessary to conduct a penetration test that pretends an actual cyber-attack. Through the collaboration with University of Illinois at Urbana-Champaign, which possesses the Tricon a safety programmable logic controller (PLC) used at nuclear power plants and develops a test-bed for nuclear power plant, a test-bed for reactor protection system (RPS) is being developed with the PLCs. Two PLCs are used to construct a simple test-bed for RPS, bi-stable processor (BP) and coincidence processor (CP). By using two PLCs, it is possible to examine cyber-attack against devices such as PLC, cyber-attack against communication between devices, and the effects of a PLC on the other PLC. Two PLCs were used to construct a test-bed for penetration test in this study. Advantages of using two or more PLCs instead of single PLC are as follows. 1) Results of cyber-attack reflecting characteristics among PLCs can be obtained. 2) Cyber-attack can be attempted using a method of attacking communication between PLCs. True data obtained can be applied to existing cyber security evaluation model to emphasize reality of the model.

  18. Testbed for High-Acuity Imaging and Stable Photometry

    Science.gov (United States)

    Gregory, James

    This proposal from MIT Lincoln Laboratory (LL) accompanies the NASA/APRA proposal enti-tled THAI-SPICE: Testbed for High-Acuity Imaging - Stable Photometry and Image-Motion Compensa-tion Experiment (submitted by Eliot Young, Southwest Research Institute). The goal of the THAI-SPICE project is to demonstrate three technologies that will help low-cost balloon-borne telescopes achieve diffraction-limited imaging: stable pointing, passive thermal stabilization and in-flight monitoring of the wave front error. This MIT LL proposal supplies a key element of the pointing stabilization component of THAI-SPICE: an electronic camera based on an orthogonaltransfer charge-coupled device (OTCCD). OTCCD cameras have been demonstrated with charge-transfer efficiencies >0.99999, noise of 90%. In addition to supplying a camera with an OTCCD detector, MIT LL will help with integration and testing of the OTCCD with the THAI-SPICE payload’s guide camera.

  19. Grounded Learning Experience: Helping Students Learn Physics through Visuo-Haptic Priming and Instruction

    Science.gov (United States)

    Huang, Shih-Chieh Douglas

    2013-01-01

    In this dissertation, I investigate the effects of a grounded learning experience on college students' mental models of physics systems. The grounded learning experience consisted of a priming stage and an instruction stage, and within each stage, one of two different types of visuo-haptic representation was applied: visuo-gestural simulation…

  20. Real-time remote diagnostic monitoring test-bed in JET

    International Nuclear Information System (INIS)

    Castro, R.; Kneupner, K.; Vega, J.; De Arcas, G.; Lopez, J.M.; Purahoo, K.; Murari, A.; Fonseca, A.; Pereira, A.; Portas, A.

    2010-01-01

    Based on the remote experimentation concept oriented to long pulse shots, a test-bed system has been implemented in JET. Its main functionality is the real-time monitoring, on remote, of a reflectometer diagnostic, to visualize different data outputs and status information. The architecture of the system is formed by: the data generator components, the data distribution system, an access control service, and the client applications. In the test-bed there is one data generator, which is the acquisition equipment associated with the reflectometer diagnostic that generates data and status information. The data distribution system has been implemented using a publishing-subscribing technology that receives data from data generators and redistributes them to client applications. And finally, for monitoring, a client application based on JAVA Web Start technology has been used. There are three interesting results from this project. The first one is the analysis of different aspects (data formats, data frame rate, data resolution, etc) related with remote real-time diagnostic monitoring oriented to long pulse experiments. The second one is the definition and implementation of an architecture, flexible enough to be applied to different types of data generated from other diagnostics, and that fits with remote access requirements. Finally, the third result is a secure system, taking into account internal networks and firewalls aspects of JET, and securing the access from remote users. For this last issue, PAPI technology has been used, enabling access control based on user attributes, enabling mobile users to monitor diagnostics in real-time, and enabling the integration of this service into the EFDA Federation (Castro et al., 2008 ).

  1. Real-time remote diagnostic monitoring test-bed in JET

    Energy Technology Data Exchange (ETDEWEB)

    Castro, R., E-mail: rodrigo.castro@ciemat.e [Asociacion EURATOM/CIEMAT para Fusion, Madrid (Spain); Kneupner, K. [EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom); Vega, J. [Asociacion EURATOM/CIEMAT para Fusion, Madrid (Spain); De Arcas, G.; Lopez, J.M. [Universidad Politecnica de Madrid, Grupo I2A2, Madrid (Spain); Purahoo, K. [EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom); Murari, A. [Associazione EURATOM-ENEA per la Fusione, Consorzio RFX, 4-35127 Padova (Italy); Fonseca, A. [Associacao EURATOM/IST, Lisbon (Portugal); Pereira, A.; Portas, A. [Asociacion EURATOM/CIEMAT para Fusion, Madrid (Spain)

    2010-07-15

    Based on the remote experimentation concept oriented to long pulse shots, a test-bed system has been implemented in JET. Its main functionality is the real-time monitoring, on remote, of a reflectometer diagnostic, to visualize different data outputs and status information. The architecture of the system is formed by: the data generator components, the data distribution system, an access control service, and the client applications. In the test-bed there is one data generator, which is the acquisition equipment associated with the reflectometer diagnostic that generates data and status information. The data distribution system has been implemented using a publishing-subscribing technology that receives data from data generators and redistributes them to client applications. And finally, for monitoring, a client application based on JAVA Web Start technology has been used. There are three interesting results from this project. The first one is the analysis of different aspects (data formats, data frame rate, data resolution, etc) related with remote real-time diagnostic monitoring oriented to long pulse experiments. The second one is the definition and implementation of an architecture, flexible enough to be applied to different types of data generated from other diagnostics, and that fits with remote access requirements. Finally, the third result is a secure system, taking into account internal networks and firewalls aspects of JET, and securing the access from remote users. For this last issue, PAPI technology has been used, enabling access control based on user attributes, enabling mobile users to monitor diagnostics in real-time, and enabling the integration of this service into the EFDA Federation (Castro et al., 2008 ).

  2. Multi-level infrastructure of interconnected testbeds of large-scale wireless sensor networks (MI2T-WSN)

    CSIR Research Space (South Africa)

    Abu-Mahfouz, Adnan M

    2012-06-01

    Full Text Available are still required for further testing before the real implementation. In this paper we propose a multi-level infrastructure of interconnected testbeds of large- scale WSNs. This testbed consists of 1000 sensor motes that will be distributed into four...

  3. The Airborne Optical Systems Testbed (AOSTB)

    Science.gov (United States)

    2017-05-31

    are the Atlantic Ocean and coastal waterways, which reflect back very little light at our SWIR operating wavelength of 1064 nm. The Airborne Optical...demonstrate our typical FOPEN capabilities, figure 5 shows two images taken over a forested area near Burlington, VT. Figure 5(a) is a 3D point...Systems Testbed (AOSTB) 1 - 6 STO-MP-SET-999 (a) (b) Fig. 5. Ladar target scan of a forested area in northern Vermont

  4. Open source IPSEC software in manned and unmanned space missions

    Science.gov (United States)

    Edwards, Jacob

    Network security is a major topic of research because cyber attackers pose a threat to national security. Securing ground-space communications for NASA missions is important because attackers could endanger mission success and human lives. This thesis describes how an open source IPsec software package was used to create a secure and reliable channel for ground-space communications. A cost efficient, reproducible hardware testbed was also created to simulate ground-space communications. The testbed enables simulation of low-bandwidth and high latency communications links to experiment how the open source IPsec software reacts to these network constraints. Test cases were built that allowed for validation of the testbed and the open source IPsec software. The test cases also simulate using an IPsec connection from mission control ground routers to points of interest in outer space. Tested open source IPsec software did not meet all the requirements. Software changes were suggested to meet requirements.

  5. Embedded Sensors and Controls to Improve Component Performance and Reliability -- Bench-scale Testbed Design Report

    Energy Technology Data Exchange (ETDEWEB)

    Melin, Alexander M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Kisner, Roger A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Drira, Anis [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Reed, Frederick K. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-09-01

    Embedded instrumentation and control systems that can operate in extreme environments are challenging due to restrictions on sensors and materials. As a part of the Department of Energy's Nuclear Energy Enabling Technology cross-cutting technology development programs Advanced Sensors and Instrumentation topic, this report details the design of a bench-scale embedded instrumentation and control testbed. The design goal of the bench-scale testbed is to build a re-configurable system that can rapidly deploy and test advanced control algorithms in a hardware in the loop setup. The bench-scale testbed will be designed as a fluid pump analog that uses active magnetic bearings to support the shaft. The testbed represents an application that would improve the efficiency and performance of high temperature (700 C) pumps for liquid salt reactors that operate in an extreme environment and provide many engineering challenges that can be overcome with embedded instrumentation and control. This report will give details of the mechanical design, electromagnetic design, geometry optimization, power electronics design, and initial control system design.

  6. A Multi-Vehicles, Wireless Testbed for Networked Control, Communications and Computing

    Science.gov (United States)

    Murray, Richard; Doyle, John; Effros, Michelle; Hickey, Jason; Low, Steven

    2002-03-01

    We have constructed a testbed consisting of 4 mobile vehicles (with 4 additional vehicles being completed), each with embedded computing and communications capability for use in testing new approaches for command and control across dynamic networks. The system is being used or is planned to be used for testing of a variety of communications-related technologies, including distributed command and control algorithms, dynamically reconfigurable network topologies, source coding for real-time transmission of data in lossy environments, and multi-network communications. A unique feature of the testbed is the use of vehicles that have second order dynamics. Requiring real-time feedback algorithms to stabilize the system while performing cooperative tasks. The testbed was constructed in the Caltech Vehicles Laboratory and consists of individual vehicles with PC-based computation and controls, and multiple communications devices (802.11 wireless Ethernet, Bluetooth, and infrared). The vehicles are freely moving, wheeled platforms propelled by high performance dotted fairs. The room contains an access points for an 802.11 network, overhead visual sensing (to allow emulation of CI'S signal processing), a centralized computer for emulating certain distributed computations, and network gateways to control and manipulate communications traffic.

  7. FloorNet: Deployment and Evaluation of a Multihop Wireless 802.11 Testbed

    Directory of Open Access Journals (Sweden)

    Zink Michael

    2010-01-01

    Full Text Available A lot of attention has been given to multihop wireless networks lately, but further research—in particular, through experimentation—is needed. This attention has motivated an increase in the number of 802.11-based deployments, both indoor and outdoor. These testbeds, which require a significant amount of resources during both deployment and maintenance, are used to run measurements in order to analyze and understand the limitation and differences between analytical or simulation-based figures and the results from real-life experimentation. This paper makes two major contributions: (i first, we describe a novel wireless multihop testbed, which we name FloorNet, that is deployed and operated under the false floor of a lab in our Computer Science building. This false floor provides a strong physical protection that prevents disconnections or misplacements, as well as radio shielding (to some extent thanks to the false floor panels—this later feature is assessed through experimentation; (ii second, by running exhaustive and controlled experiments we are able to analyze the performance limits of commercial off-the-shelf hardware, as well as to derive practical design criteria for the deployment and configuration of mesh networks. These results both provide valuable insights of wireless multihop performance and prove that FloorNet constitutes a valuable asset to research on wireless mesh networks.

  8. ASE-BAN, a Wireless Body Area Network Testbed

    DEFF Research Database (Denmark)

    Madsen, Jens Kargaard; Karstoft, Henrik; Toftegaard, Thomas Skjødeberg

    2010-01-01

    /actuators attached to the body and a host server application. The gateway uses the BlackFin BF533 processor from Analog Devices, and uses Bluetooth for wireless communication. Two types of sensors are attached to the network: an electro-cardio-gram sensor and an oximeter sensor. The testbed has been successfully...

  9. LOS Throughput Measurements in Real-Time with a 128-Antenna Massive MIMO Testbed

    OpenAIRE

    Harris, Paul; Zhang, Siming; Beach, Mark; Mellios, Evangelos; Nix, Andrew; Armour, Simon; Doufexi, Angela; Nieman, Karl; Kundargi, Nikhil

    2017-01-01

    This paper presents initial results for a novel 128-antenna massive Multiple-Input, Multiple- Output (MIMO) testbed developed through Bristol Is Open in collaboration with National Instruments and Lund University. We believe that the results presented here validate the adoption of massive MIMO as a key enabling technology for 5G and pave the way for further pragmatic research by the massive MIMO community. The testbed operates in real-time with a Long-Term Evolution (LTE)-like PHY in Time Div...

  10. Operation Duties on the F-15B Research Testbed

    Science.gov (United States)

    Truong, Samson S.

    2010-01-01

    This presentation entails what I have done this past summer for my Co-op tour in the Operations Engineering Branch. Activities included supporting the F-15B Research Testbed, supporting the incoming F-15D models, design work, and other operations engineering duties.

  11. Construction of test-bed system of voltage management system to ...

    African Journals Online (AJOL)

    Construction of test-bed system of voltage management system to apply physical power system. ... Journal of Fundamental and Applied Sciences ... system of voltage management system (VMS) in order to apply physical power system.

  12. Implementation of a Wireless Time Distribution Testbed Protected with Quantum Key Distribution

    Energy Technology Data Exchange (ETDEWEB)

    Bonior, Jason D [ORNL; Evans, Philip G [ORNL; Sheets, Gregory S [ORNL; Jones, John P [ORNL; Flynn, Toby H [ORNL; O' Neil, Lori Ross [Pacific Northwest National Laboratory (PNNL); Hutton, William [Pacific Northwest National Laboratory (PNNL); Pratt, Richard [Pacific Northwest National Laboratory (PNNL); Carroll, Thomas E. [Pacific Northwest National Laboratory (PNNL)

    2017-01-01

    Secure time transfer is critical for many timesensitive applications. the Global Positioning System (GPS) which is often used for this purpose has been shown to be susceptible to spoofing attacks. Quantum Key Distribution offers a way to securely generate encryption keys at two locations. Through careful use of this information it is possible to create a system that is more resistant to spoofing attacks. In this paper we describe our work to create a testbed which utilizes QKD and traditional RF links. This testbed will be used for the development of more secure and spoofing resistant time distribution protocols.

  13. Network-Centric Maritime Radiation Awareness and Interdiction Experiments: C2 Experimentation

    International Nuclear Information System (INIS)

    Bordetsky, A; Dougan, A D; Nekoogar, F

    2006-01-01

    The paper addresses technological and operational challenges of developing a global plug-and-play Maritime Domain Security testbed for the Global War on Terrorism mission. This joint NPS-LLNL project is based on the NPS Tactical Network Topology (TNT) composed of long-haul OFDM networks combined with self-forming wireless mesh links to air, surface, ground, and underwater unmanned vehicles. This long-haul network is combined with ultra-wideband (UWB) communications systems for wireless communications in harsh radio propagation channels. LLNL's UWB communication prototypes are designed to overcome shortcomings of the present narrowband communications systems in heavy metallic and constricted corridors inside ships. In the center of our discussion are networking solutions for the Maritime Interdiction Operation (MIO) Experiments in which geographically distributed command centers and subject matter experts collaborate with the Boarding Party in real time to facilitate situational understanding and course of action selection. The most recent experiment conducted via the testbed extension to the Alameda Island exercised several key technologies aimed at improving MIO. These technologies included UWB communications from within the ship to Boarding Party leader sending data files and pictures, advanced radiation detection equipment for search and identification, biometric equipment to record and send fingerprint files to facilitate rapid positive identification of crew members, and the latest updates of the NPS Tactical Network Topology facilitating reachback to LLNL, Biometric Fusion Center, USCG, and DTRA experts

  14. Earth at Rest. Aesthetic Experience and Students' Grounding in Science Education

    Science.gov (United States)

    Østergaard, Edvin

    2017-07-01

    Focus of this article is the current situation characterized by students' de-rootedness and possible measures to improve the situation within the frame of education for sustainable development. My main line of argument is that science teachers can practice teaching in such a way that students are brought in deeper contact to the environment. I discuss efforts to promote aesthetic experience in science class and in science teacher education. Within a wide range of definitions, my main understanding of aesthetic experience is that of pre-conceptual experience, relational to the environment and incorporated in students' embodied knowledge. I ground the idea of Earth at rest in Husserl's phenomenological philosophy and Heidegger's notion of science' deprivation of the world. A critique of the ontological reversal leads to an ontological re-reversal that implies giving lifeworld experience back its value and rooting scientific concepts in students' everyday lives. Six aspects of facilitating grounding in sustainability-oriented science teaching and teacher education are highlighted and discussed: students' everyday knowledge and experience, aesthetic experience and grounding, fostering aesthetic sensibility, cross-curricular integration with art, ontological and epistemological aspects, and belongingness and (re-)connection to Earth. I conclude that both science students and student-teachers need to practice their sense of caring and belonging, as well as refining their sensibility towards the world. With an intension of educating for a sustainable development, there is an urgent need for a critical discussion in science education when it comes to engaging learners for a sustainable future.

  15. Phased Array Antenna Testbed Development at the NASA Glenn Research Center

    Science.gov (United States)

    Lambert, Kevin M.; Kubat, Gregory; Johnson, Sandra K.; Anzic, Godfrey

    2003-01-01

    Ideal phased array antennas offer advantages for communication systems, such as wide-angle scanning and multibeam operation, which can be utilized in certain NASA applications. However, physically realizable, electronically steered, phased array antennas introduce additional system performance parameters, which must be included in the evaluation of the system. The NASA Glenn Research Center (GRC) is currently conducting research to identify these parameters and to develop the tools necessary to measure them. One of these tools is a testbed where phased array antennas may be operated in an environment that simulates their use. This paper describes the development of the testbed and its use in characterizing a particular K-Band, phased array antenna.

  16. A Matlab-Based Testbed for Integration, Evaluation and Comparison of Heterogeneous Stereo Vision Matching Algorithms

    Directory of Open Access Journals (Sweden)

    Raul Correal

    2016-11-01

    Full Text Available Stereo matching is a heavily researched area with a prolific published literature and a broad spectrum of heterogeneous algorithms available in diverse programming languages. This paper presents a Matlab-based testbed that aims to centralize and standardize this variety of both current and prospective stereo matching approaches. The proposed testbed aims to facilitate the application of stereo-based methods to real situations. It allows for configuring and executing algorithms, as well as comparing results, in a fast, easy and friendly setting. Algorithms can be combined so that a series of processes can be chained and executed consecutively, using the output of a process as input for the next; some additional filtering and image processing techniques have been included within the testbed for this purpose. A use case is included to illustrate how these processes are sequenced and its effect on the results for real applications. The testbed has been conceived as a collaborative and incremental open-source project, where its code is accessible and modifiable, with the objective of receiving contributions and releasing future versions to include new algorithms and features. It is currently available online for the research community.

  17. Designing, Implementing and Documenting the Atlas Networking Test-bed.

    CERN Document Server

    Martinsen, Hans Åge

    The A Toroidal LHC ApparatuS (Atlas) experiment at the Large Hadron Colider (LHC) in European Organization for Nuclear Research (CERN), Geneva is a production environment. To develop new architectures, test new equipment and evaluate new technologies a well supported test bench is needed. A new one is now being commissioned and I will take a leading role in its development, commissioning and operation. This thesis will cover the requirements, the implementation, the documentation and the approach to the different challenges in implementing the testbed. I will be joining the project in the early stages and start by following the work that my colleagues are doing and then, as I get a better understanding, more responsibility will be given to me. To be able to suggest and implement solutions I will have to understand what the requirements are and how to achieve these requirements with the given resources.

  18. LTE-Advanced/WLAN testbed

    OpenAIRE

    Plaisner, Denis

    2017-01-01

    Táto práca sa zaoberá skúmaním a vyhodnocovaním komunikácie štandardov LTE-Advance a WiFi (IEEE 802.11n/ac). Pri jednotlivých štandardoch je preskúmaný chybový parameter EVM. Pre prácu s jednotlivými štandardmi je navrhnuté univerzálne pracovisko (testbed). Toto univerzálne pracovisko slúži na nastavovanie vysielacieho a prijímacieho zariadenia a na spracovávanie prenášaných signálov a ich vyhodnocovanie. Pre túto prácu je vybrané prostredie Matlab, cez ktoré sa ovládajú použité prístroje ako...

  19. Experimenting Galileo on Board the International Space Station

    Science.gov (United States)

    Fantinato, Samuele; Pozzobon, Oscar; Sands, Obed S.; Welch, Bryan W.; Clapper, Carolyn J.; Miller, James J.; Gamba, Giovanni; Chiara, Andrea; Montagner, Stefano; Giordano, Pietro; hide

    2016-01-01

    feasibility of a dual frequency implementation (L1E1+L5E5a) in the same SDR platform.2)Qualification and test the GalileoGPS waveform using ground systems available at the NASA Glenn Research Center. Experimenters can have access to two SCaN Testbed ground based systems for development and verification: the Experimenter Development System (EDS) that is intended to provide initial opportunity for software testing and basic functional validation and the Ground Integration Unit (GIU) that is a high fidelity version of the SCaN Testbed flight system and is therefore used for more controlled final development testing and verification testing.3)Perform in-orbit validation and experimentation: The experimentation phase will consists on the collection of raw measurements (pseudorange, Carrier phase, CN0) in space, assessment on the quality of the measurements and the receiver performances in terms of signal acquisition, tracking, etc. Finally computation of positioning in space (Position, Velocity and time) and assessment of its performance.(Complete abstract in attached document).

  20. Resisting Coherence: Trans Men's Experiences and the Use of Grounded Theory Methods

    Science.gov (United States)

    Catalano, D. Chase J.

    2017-01-01

    In this methodological reflective manuscript, I explore my decision to use a grounded theoretical approach to my dissertation study on trans* men in higher education. Specifically, I question whether grounded theory as a methodology is capable of capturing the complexity and capaciousness of trans*-masculine experiences. Through the lenses of…

  1. A MIMO-OFDM Testbed for Wireless Local Area Networks

    Directory of Open Access Journals (Sweden)

    Conrat Jean-Marc

    2006-01-01

    Full Text Available We describe the design steps and final implementation of a MIMO OFDM prototype platform developed to enhance the performance of wireless LAN standards such as HiperLAN/2 and 802.11, using multiple transmit and multiple receive antennas. We first describe the channel measurement campaign used to characterize the indoor operational propagation environment, and analyze the influence of the channel on code design through a ray-tracing channel simulator. We also comment on some antenna and RF issues which are of importance for the final realization of the testbed. Multiple coding, decoding, and channel estimation strategies are discussed and their respective performance-complexity trade-offs are evaluated over the realistic channel obtained from the propagation studies. Finally, we present the design methodology, including cross-validation of the Matlab, C++, and VHDL components, and the final demonstrator architecture. We highlight the increased measured performance of the MIMO testbed over the single-antenna system.

  2. A Testbed Environment for Buildings-to-Grid Cyber Resilience Research and Development

    Energy Technology Data Exchange (ETDEWEB)

    Sridhar, Siddharth; Ashok, Aditya; Mylrea, Michael E.; Pal, Seemita; Rice, Mark J.; Gourisetti, Sri Nikhil Gup

    2017-09-19

    The Smart Grid is characterized by the proliferation of advanced digital controllers at all levels of its operational hierarchy from generation to end consumption. Such controllers within modern residential and commercial buildings enable grid operators to exercise fine-grained control over energy consumption through several emerging Buildings-to-Grid (B2G) applications. Though this capability promises significant benefits in terms of operational economics and improved reliability, cybersecurity weaknesses in the supporting infrastructure could be exploited to cause a detrimental effect and this necessitates focused research efforts on two fronts. First, the understanding of how cyber attacks in the B2G space could impact grid reliability and to what extent. Second, the development and validation of cyber-physical application-specific countermeasures that are complementary to traditional infrastructure cybersecurity mechanisms for enhanced cyber attack detection and mitigation. The PNNL B2G testbed is currently being developed to address these core research needs. Specifically, the B2G testbed combines high-fidelity buildings+grid simulators, industry-grade building automation and Supervisory Control and Data Acquisition (SCADA) systems in an integrated, realistic, and reconfigurable environment capable of supporting attack-impact-detection-mitigation experimentation. In this paper, we articulate the need for research testbeds to model various B2G applications broadly by looking at the end-to-end operational hierarchy of the Smart Grid. Finally, the paper not only describes the architecture of the B2G testbed in detail, but also addresses the broad spectrum of B2G resilience research it is capable of supporting based on the smart grid operational hierarchy identified earlier.

  3. A method for optical ground station reduce alignment error in satellite-ground quantum experiments

    Science.gov (United States)

    He, Dong; Wang, Qiang; Zhou, Jian-Wei; Song, Zhi-Jun; Zhong, Dai-Jun; Jiang, Yu; Liu, Wan-Sheng; Huang, Yong-Mei

    2018-03-01

    A satellite dedicated for quantum science experiments, has been developed and successfully launched from Jiuquan, China, on August 16, 2016. Two new optical ground stations (OGSs) were built to cooperate with the satellite to complete satellite-ground quantum experiments. OGS corrected its pointing direction by satellite trajectory error to coarse tracking system and uplink beacon sight, therefore fine tracking CCD and uplink beacon optical axis alignment accuracy was to ensure that beacon could cover the quantum satellite in all time when it passed the OGSs. Unfortunately, when we tested specifications of the OGSs, due to the coarse tracking optical system was commercial telescopes, the change of position of the target in the coarse CCD was up to 600μrad along with the change of elevation angle. In this paper, a method of reduce alignment error between beacon beam and fine tracking CCD is proposed. Firstly, OGS fitted the curve of target positions in coarse CCD along with the change of elevation angle. Secondly, OGS fitted the curve of hexapod secondary mirror positions along with the change of elevation angle. Thirdly, when tracking satellite, the fine tracking error unloaded on the real-time zero point position of coarse CCD which computed by the firstly calibration data. Simultaneously the positions of the hexapod secondary mirror were adjusted by the secondly calibration data. Finally the experiment result is proposed. Results show that the alignment error is less than 50μrad.

  4. A demonstration of remote survey and characterization of a buried waste site using the SRIP [Soldier Robot Interface Project] testbed

    International Nuclear Information System (INIS)

    Burks, B.L.; Richardson, B.S.; Armstrong, G.A.; Hamel, W.R.; Jansen, J.F.; Killough, S.M.; Thompson, D.H.; Emery, M.S.

    1990-01-01

    During FY 1990, the Oak Ridge National Laboratory (ORNL) supported the Department of Energy (DOE) Environmental Restoration and Waste Management (ER ampersand WM) Office of Technology Development through several projects including the development of a semiautonomous survey of a buried waste site using a remotely operated all-terrain robotic testbed borrowed from the US Army. The testbed was developed for the US Army's Human Engineering Laboratory (HEL) for the US Army's Soldier Robot Interface Project (SRIP). Initial development of the SRIP testbed was performed by a team including ORNL, HEL, Tooele Army Depot, and Odetics, Inc., as an experimental testbed for a variety of human factors issues related to military applications of robotics. The SRIP testbed was made available to the DOE and ORNL for the further development required for a remote landfill survey. The robot was modified extensively, equipped with environmental sensors, and used to demonstrate an automated remote survey of Solid Waste Storage Area No. 3 (SWSA 3) at ORNL on Tuesday, September 18, 1990. Burial trenches in this area containing contaminated materials were covered with soil nearly twenty years ago. This paper describes the SRIP testbed and work performed in FY 1990 to demonstrate a semiautonomous landfill survey at ORNL. 5 refs

  5. The Segmented Aperture Interferometric Nulling Testbed (SAINT) I: overview and air-side system description

    Science.gov (United States)

    Hicks, Brian A.; Lyon, Richard G.; Petrone, Peter; Ballard, Marlin; Bolcar, Matthew R.; Bolognese, Jeff; Clampin, Mark; Dogoda, Peter; Dworzanski, Daniel; Helmbrecht, Michael A.; Koca, Corina; Shiri, Ron

    2016-07-01

    This work presents an overview of the Segmented Aperture Interferometric Nulling Testbed (SAINT), a project that will pair an actively-controlled macro-scale segmented mirror with the Visible Nulling Coronagraph (VNC). SAINT will incorporate the VNC's demonstrated wavefront sensing and control system to refine and quantify end-to-end high-contrast starlight suppression performance. This pathfinder testbed will be used as a tool to study and refine approaches to mitigating instabilities and complex diffraction expected from future large segmented aperture telescopes.

  6. On-wire lithography-generated molecule-based transport junctions: a new testbed for molecular electronics.

    Science.gov (United States)

    Chen, Xiaodong; Jeon, You-Moon; Jang, Jae-Won; Qin, Lidong; Huo, Fengwei; Wei, Wei; Mirkin, Chad A

    2008-07-02

    On-wire lithography (OWL) fabricated nanogaps are used as a new testbed to construct molecular transport junctions (MTJs) through the assembly of thiolated molecular wires across a nanogap formed between two Au electrodes. In addition, we show that one can use OWL to rapidly characterize a MTJ and optimize gap size for two molecular wires of different dimensions. Finally, we have used this new testbed to identify unusual temperature-dependent transport mechanisms for alpha,omega-dithiol terminated oligo(phenylene ethynylene).

  7. Termite: Emulation Testbed for Encounter Networks

    Directory of Open Access Journals (Sweden)

    Rodrigo Bruno

    2015-08-01

    Full Text Available Cutting-edge mobile devices like smartphones and tablets are equipped with various infrastructureless wireless interfaces, such as WiFi Direct and Bluetooth. Such technologies allow for novel mobile applications that take advantage of casual encounters between co-located users. However, the need to mimic the behavior of real-world encounter networks makes testing and debugging of such applications hard tasks. We present Termite, an emulation testbed for encounter networks. Our system allows developers to run their applications on a virtual encounter network emulated by software. Developers can model arbitrary encounter networks and specify user interactions on the emulated virtual devices. To facilitate testing and debugging, developers can place breakpoints, inspect the runtime state of virtual nodes, and run experiments in a stepwise fashion. Termite defines its own Petri Net variant to model the dynamically changing topology and synthesize user interactions with virtual devices. The system is designed to efficiently multiplex an underlying emulation hosting infrastructure across multiple developers, and to support heterogeneous mobile platforms. Our current system implementation supports virtual Android devices communicating over WiFi Direct networks and runs on top of a local cloud infrastructure. We evaluated our system using emulator network traces, and found that Termite is expressive and performs well.

  8. Real-Time Simulation and Hardware-in-the-Loop Testbed for Distribution Synchrophasor Applications

    Directory of Open Access Journals (Sweden)

    Matthias Stifter

    2018-04-01

    Full Text Available With the advent of Distribution Phasor Measurement Units (D-PMUs and Micro-Synchrophasors (Micro-PMUs, the situational awareness in power distribution systems is going to the next level using time-synchronization. However, designing, analyzing, and testing of such accurate measurement devices are still challenging. Due to the lack of available knowledge and sufficient history for synchrophasors’ applications at the power distribution level, the realistic simulation, and validation environments are essential for D-PMU development and deployment. This paper presents a vendor agnostic PMU real-time simulation and hardware-in-the-Loop (PMU-RTS-HIL testbed, which helps in multiple PMUs validation and studies. The network of real and virtual PMUs was built in a full time-synchronized environment for PMU applications’ validation. The proposed testbed also includes an emulated communication network (CNS layer to replicate bandwidth, packet loss and collisions conditions inherent to the PMUs data streams’ issues. Experimental results demonstrate the flexibility and scalability of the developed PMU-RTS-HIL testbed by producing large amounts of measurements under typical normal and abnormal distribution grid operation conditions.

  9. Embedded Sensors and Controls to Improve Component Performance and Reliability -- Loop-scale Testbed Design Report

    Energy Technology Data Exchange (ETDEWEB)

    Melin, Alexander M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Kisner, Roger A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-09-01

    Embedded instrumentation and control systems that can operate in extreme environments are challenging to design and operate. Extreme environments limit the options for sensors and actuators and degrade their performance. Because sensors and actuators are necessary for feedback control, these limitations mean that designing embedded instrumentation and control systems for the challenging environments of nuclear reactors requires advanced technical solutions that are not available commercially. This report details the development of testbed that will be used for cross-cutting embedded instrumentation and control research for nuclear power applications. This research is funded by the Department of Energy's Nuclear Energy Enabling Technology program's Advanced Sensors and Instrumentation topic. The design goal of the loop-scale testbed is to build a low temperature pump that utilizes magnetic bearing that will be incorporated into a water loop to test control system performance and self-sensing techniques. Specifically, this testbed will be used to analyze control system performance in response to nonlinear and cross-coupling fluid effects between the shaft axes of motion, rotordynamics and gyroscopic effects, and impeller disturbances. This testbed will also be used to characterize the performance losses when using self-sensing position measurement techniques. Active magnetic bearings are a technology that can reduce failures and maintenance costs in nuclear power plants. They are particularly relevant to liquid salt reactors that operate at high temperatures (700 C). Pumps used in the extreme environment of liquid salt reactors provide many engineering challenges that can be overcome with magnetic bearings and their associated embedded instrumentation and control. This report will give details of the mechanical design and electromagnetic design of the loop-scale embedded instrumentation and control testbed.

  10. Using the ISS as a testbed to prepare for the next generation of space-based telescopes

    Science.gov (United States)

    Postman, Marc; Sparks, William B.; Liu, Fengchuan; Ess, Kim; Green, Joseph; Carpenter, Kenneth G.; Thronson, Harley; Goullioud, Renaud

    2012-09-01

    The infrastructure available on the ISS provides a unique opportunity to develop the technologies necessary to assemble large space telescopes. Assembling telescopes in space is a game-changing approach to space astronomy. Using the ISS as a testbed enables a concentration of resources on reducing the technical risks associated with integrating the technologies, such as laser metrology and wavefront sensing and control (WFS&C), with the robotic assembly of major components including very light-weight primary and secondary mirrors and the alignment of the optical elements to a diffraction-limited optical system in space. The capability to assemble the optical system and remove and replace components via the existing ISS robotic systems such as the Special Purpose Dexterous Manipulator (SPDM), or by the ISS Flight Crew, allows for future experimentation as well as repair if necessary. In 2015, first light will be obtained by the Optical Testbed and Integration on ISS eXperiment (OpTIIX), a small 1.5-meter optical telescope assembled on the ISS. The primary objectives of OpTIIX include demonstrating telescope assembly technologies and end-to-end optical system technologies that will advance future large optical telescopes.

  11. An SDR-Based Real-Time Testbed for GNSS Adaptive Array Anti-Jamming Algorithms Accelerated by GPU

    Directory of Open Access Journals (Sweden)

    Hailong Xu

    2016-03-01

    Full Text Available Nowadays, software-defined radio (SDR has become a common approach to evaluate new algorithms. However, in the field of Global Navigation Satellite System (GNSS adaptive array anti-jamming, previous work has been limited due to the high computational power demanded by adaptive algorithms, and often lack flexibility and configurability. In this paper, the design and implementation of an SDR-based real-time testbed for GNSS adaptive array anti-jamming accelerated by a Graphics Processing Unit (GPU are documented. This testbed highlights itself as a feature-rich and extendible platform with great flexibility and configurability, as well as high computational performance. Both Space-Time Adaptive Processing (STAP and Space-Frequency Adaptive Processing (SFAP are implemented with a wide range of parameters. Raw data from as many as eight antenna elements can be processed in real-time in either an adaptive nulling or beamforming mode. To fully take advantage of the parallelism resource provided by the GPU, a batched method in programming is proposed. Tests and experiments are conducted to evaluate both the computational and anti-jamming performance. This platform can be used for research and prototyping, as well as a real product in certain applications.

  12. Radiation beamline testbeds for the simulation of planetary and spacecraft environments for human and robotic mission risk assessment

    Science.gov (United States)

    Wilkins, Richard

    The Center for Radiation Engineering and Science for Space Exploration (CRESSE) at Prairie View A&M University, Prairie View, Texas, USA, is establishing an integrated, multi-disciplinary research program on the scientific and engineering challenges faced by NASA and the inter-national space community caused by space radiation. CRESSE focuses on space radiation research directly applicable to astronaut health and safety during future long term, deep space missions, including Martian, lunar, and other planetary body missions beyond low earth orbit. The research approach will consist of experimental and theoretical radiation modeling studies utilizing particle accelerator facilities including: 1. NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory; 2. Proton Synchrotron at Loma Linda University Med-ical Center; and 3. Los Alamos Neutron Science Center (LANSCE) at Los Alamos National Laboratory. Specifically, CRESSE investigators are designing, developing, and building experimental test beds that simulate the lunar and Martian radiation environments for experiments focused on risk assessment for astronauts and instrumentation. The testbeds have been designated the Bioastronautics Experimental Research Testbeds for Environmental Radiation Nostrum Investigations and Education (BERT and ERNIE). The designs of BERT and ERNIE will allow for a high degree of flexibility and adaptability to modify experimental configurations to simulate planetary surface environments, planetary habitats, and spacecraft interiors. In the nominal configuration, BERT and ERIE will consist of a set of experimental zones that will simulate the planetary atmosphere (Solid CO2 in the case of the Martian surface.), the planetary surface, and sub-surface regions. These experimental zones can be used for dosimetry, shielding, biological, and electronic effects radiation studies in support of space exploration missions. BERT and ERNIE are designed to be compatible with the

  13. Torpedo and countermeasures modelling in the Torpedo Defence System Testbed

    NARCIS (Netherlands)

    Benders, F.P.A.; Witberg, R.R.; H.J. Grootendorst, H.J.

    2002-01-01

    Several years ago, TNO-FEL started the development of the Torpedo Defence System Testbed (TDSTB) based on the TORpedo SIMulation (TORSIM) model and the Maritime Operations Simulation and Evaluation System (MOSES). MOSES provides the simulation and modelling environment for the evaluation and

  14. James Webb Space Telescope Optical Simulation Testbed: Segmented Mirror Phase Retrieval Testing

    Science.gov (United States)

    Laginja, Iva; Egron, Sylvain; Brady, Greg; Soummer, Remi; Lajoie, Charles-Philippe; Bonnefois, Aurélie; Long, Joseph; Michau, Vincent; Choquet, Elodie; Ferrari, Marc; Leboulleux, Lucie; Mazoyer, Johan; N’Diaye, Mamadou; Perrin, Marshall; Petrone, Peter; Pueyo, Laurent; Sivaramakrishnan, Anand

    2018-01-01

    The James Webb Space Telescope (JWST) Optical Simulation Testbed (JOST) is a hardware simulator designed to produce JWST-like images. A model of the JWST three mirror anastigmat is realized with three lenses in form of a Cooke Triplet, which provides JWST-like optical quality over a field equivalent to a NIRCam module, and an Iris AO segmented mirror with hexagonal elements is standing in for the JWST segmented primary. This setup successfully produces images extremely similar to NIRCam images from cryotesting in terms of the PSF morphology and sampling relative to the diffraction limit.The testbed is used for staff training of the wavefront sensing and control (WFS&C) team and for independent analysis of WFS&C scenarios of the JWST. Algorithms like geometric phase retrieval (GPR) that may be used in flight and potential upgrades to JWST WFS&C will be explored. We report on the current status of the testbed after alignment, implementation of the segmented mirror, and testing of phase retrieval techniques.This optical bench complements other work at the Makidon laboratory at the Space Telescope Science Institute, including the investigation of coronagraphy for segmented aperture telescopes. Beyond JWST we intend to use JOST for WFS&C studies for future large segmented space telescopes such as LUVOIR.

  15. Analysis, modeling, and simulation (AMS) testbed development and evaluation to support dynamic mobility applications (DMA) and active transportation and demand management (ATDM) programs : Dallas testbed analysis plan.

    Science.gov (United States)

    2016-06-16

    The primary objective of this project is to develop multiple simulation Testbeds/transportation models to evaluate theimpacts of DMA connected vehicle applications and the active and dynamic transportation management (ATDM)strategies. The outputs (mo...

  16. Advanced gamma ray balloon experiment ground checkout and data analysis

    Science.gov (United States)

    Blackstone, M.

    1976-01-01

    A software programming package to be used in the ground checkout and handling of data from the advanced gamma ray balloon experiment is described. The Operator's Manual permits someone unfamiliar with the inner workings of the software system (called LEO) to operate on the experimental data as it comes from the Pulse Code Modulation interface, converting it to a form for later analysis, and monitoring the program of an experiment. A Programmer's Manual is included.

  17. Solar Constant (SOLCON) Experiment: Ground Support Equipment (GSE) software development

    Science.gov (United States)

    Gibson, M. Alan; Thomas, Susan; Wilson, Robert

    1991-01-01

    The Solar Constant (SOLCON) Experiment, the objective of which is to determine the solar constant value and its variability, is scheduled for launch as part of the Space Shuttle/Atmospheric Laboratory for Application and Science (ATLAS) spacelab mission. The Ground Support Equipment (GSE) software was developed to monitor and analyze the SOLCON telemetry data during flight and to test the instrument on the ground. The design and development of the GSE software are discussed. The SOLCON instrument was tested during Davos International Solar Intercomparison, 1989 and the SOLCON data collected during the tests are analyzed to study the behavior of the instrument.

  18. Network-Centric Maritime Radiation Awareness and Interdiction Experiments: C2 Experimentation

    Energy Technology Data Exchange (ETDEWEB)

    Bordetsky, A; Dougan, A D; Nekoogar, F

    2006-08-07

    The paper addresses technological and operational challenges of developing a global plug-and-play Maritime Domain Security testbed for the Global War on Terrorism mission. This joint NPS-LLNL project is based on the NPS Tactical Network Topology (TNT) composed of long-haul OFDM networks combined with self-forming wireless mesh links to air, surface, ground, and underwater unmanned vehicles. This long-haul network is combined with ultra-wideband (UWB) communications systems for wireless communications in harsh radio propagation channels. LLNL's UWB communication prototypes are designed to overcome shortcomings of the present narrowband communications systems in heavy metallic and constricted corridors inside ships. In the center of our discussion are networking solutions for the Maritime Interdiction Operation (MIO) Experiments in which geographically distributed command centers and subject matter experts collaborate with the Boarding Party in real time to facilitate situational understanding and course of action selection. The most recent experiment conducted via the testbed extension to the Alameda Island exercised several key technologies aimed at improving MIO. These technologies included UWB communications from within the ship to Boarding Party leader sending data files and pictures, advanced radiation detection equipment for search and identification, biometric equipment to record and send fingerprint files to facilitate rapid positive identification of crew members, and the latest updates of the NPS Tactical Network Topology facilitating reachback to LLNL, Biometric Fusion Center, USCG, and DTRA experts.

  19. The SPQR experiment: detecting damage to orbiting spacecraft with ground-based telescopes

    Science.gov (United States)

    Paolozzi, Antonio; Porfilio, Manfredi; Currie, Douglas G.; Dantowitz, Ronald F.

    2007-09-01

    The objective of the Specular Point-like Quick Reference (SPQR) experiment was to evaluate the possibility of improving the resolution of ground-based telescopic imaging of manned spacecraft in orbit. The concept was to reduce image distortions due to atmospheric turbulence by evaluating the Point Spread Function (PSF) of a point-like light reference and processing the spacecraft image accordingly. The target spacecraft was the International Space Station (ISS) and the point-like reference was provided by a laser beam emitted by the ground station and reflected back to the telescope by a Cube Corner Reflector (CCR) mounted on an ISS window. The ultimate objective of the experiment was to demonstrate that it is possible to image spacecraft in Low Earth Orbit (LEO) with a resolution of 20 cm, which would have probably been sufficient to detect the damage which caused the Columbia disaster. The experiment was successfully performed from March to May 2005. The paper provides an overview of the SPQR experiment.

  20. Digital pathology: DICOM-conform draft, testbed, and first results.

    Science.gov (United States)

    Zwönitzer, Ralf; Kalinski, Thomas; Hofmann, Harald; Roessner, Albert; Bernarding, Johannes

    2007-09-01

    Hospital information systems are state of the art nowadays. Therefore, Digital Pathology, also labelled as Virtual Microscopy, has gained increased attention. Triggered by radiology, standardized information models and workflows were world-wide defined based on DICOM. However, DICOM-conform integration of Digital Pathology into existing clinical information systems imposes new problems requiring specific solutions concerning the huge amount of data as well as the special structure of the data to be managed, transferred, and stored. We implemented a testbed to realize and evaluate the workflow of digitized slides from acquisition to archiving. The experiences led to the draft of a DICOM-conform information model that accounted for extensions, definitions, and technical requirements necessary to integrate digital pathology in a hospital-wide DICOM environment. Slides were digitized, compressed, and could be viewed remotely. Real-time transfer of the huge amount of data was optimized using streaming techniques. Compared to a recent discussion in the DICOM Working Group for Digital Pathology (WG26) our experiences led to a preference of a JPEG2000/JPIP-based streaming of the whole slide image. The results showed that digital pathology is feasible but strong efforts by users and vendors are still necessary to integrate Digital Pathology into existing information systems.

  1. Wireless experiments on a Motorola mesh testbed.

    Energy Technology Data Exchange (ETDEWEB)

    Riblett, Loren E., Jr.; Wiseman, James M.; Witzke, Edward L.

    2010-06-01

    Motomesh is a Motorola product that performs mesh networking at both the client and access point levels and allows broadband mobile data connections with or between clients moving at vehicular speeds. Sandia National aboratories has extensive experience with this product and its predecessors in infrastructure-less mobile environments. This report documents experiments, which characterize certain aspects of how the Motomesh network performs when obile units are added to a fixed network infrastructure.

  2. Using school grounds for nature studies: An exploratory study of elementary teachers' experiences

    Science.gov (United States)

    Willis, Tamra Lee

    2001-06-01

    The purpose of this study was to gain understanding of the experiences of elementary teachers who used school grounds to do nature studies. Following an inductive, naturalistic approach, the goal was to explore the phenomenon using words of teachers as guides to understanding. Interviews were conducted with a purposeful sampling of ten quality public school teachers in grades K--5 who were well-known for their schoolyard nature programs. Interview questions were focused by a theoretical framework of environmental cognition. Data were gathered about how teachers came to use the outdoors to teach and how they experienced teaching nature studies on the school grounds. A conceptual model of Quality Teachers of Schoolyard Nature Studies was delineated. The model consisted of three components: teacher past and present experiences with nature, teacher beliefs relevant to using the school grounds for nature studies, and teacher action efficacy pertaining to schoolyard nature programs. The model suggested a relationship between teachers' personal experiences' with nature and their beliefs about sharing nature with children. In addition, the model connected teachers' beliefs about schoolyard nature to their action efficacy, i.e. action behavior reflected through motivation and commitment. The participants shared many common experiences and beliefs. Most had extensive childhood experiences in nature and memories of adults who shared nature with them. They did not consider themselves nature experts, but felt they knew the basics of natural science from their own experiences outdoors and from working with children. The teachers' beliefs about schoolyard nature studies developed from several dimensions of their lives: experiences with nature, experiences teaching, and experiences with students. They were motivated to share nature with students on the school grounds by their beliefs that students would come to appreciate and understand nature, just as they had during their own

  3. Real-Time Remote Diagnostic Monitoring Test-bed in JET

    Energy Technology Data Exchange (ETDEWEB)

    Castro, R. [Asociation Euratom/CIEMAT para Fusion, Madrid (Spain); Kneupner, K.; Purahoo, K. [EURATOM/UKAEA Fusion Association, Abingdon (United Kingdom); Vega, J.; Pereira, A.; Portas, A. [Association EuratomCIEMAT para Fusion, Madrid (Spain); De Arcas, G.; Lopez, J.M. [Universidad Politecnica de Madrid (Spain); Murari, A. [Consorzio RFX, Padova (Italy); Fonseca, A. [Associacao URATOM/IST, Lisboa (Portugal); Contributors, J.E. [JET-EFDA, Abingdon (United Kingdom)

    2009-07-01

    Based on the remote experimentation concept oriented to long pulse shots, a test-bed system has been implemented in JET. It integrates 2 functionalities. The first one is the real-time monitoring, on remote, of a reflectometer diagnostic, to visualize different data outputs and status information. The second one is the integration of dotJET (Diagnostic Overview Tool for JET), which internally provides at JET an overview about the current diagnostic systems state, in order to monitor, on remote, JET diagnostics status. The architecture of the system is formed by: the data generator components, the data distribution system, an access control service, and the client applications. In the test-bed there are two data generators: the acquisition equipment associated with the reflectometer diagnostic that generates data and status information, and dotJET server that centralize the access to the status information of JET diagnostics. The data distribution system has been implemented using a publishing-subscribing technology that receives data from data generators and redistributes them to client applications. And finally, for monitoring, a client application based on Java Web Start technology, and a dotJET client application have been used. There are 3 interesting results from this project. The first one is the analysis of different aspects (data formats, data frame rate, data resolution, etc) related with remote real-time diagnostic monitoring oriented to long pulse experiments. The second one is the definition and implementation of a flexible enough architecture, to be applied to different types of data generated from other diagnostics, and that fits with remote access requirements; and the third one is to have achieved a secure system, taking into account internal networks and firewalls aspects in JET, and securing the access from remote users. For this last issue, PAPI technology has been used, enabling access control based on user attributes, enabling mobile users to

  4. Conceptual Design and Cost Estimate of a Subsonic NASA Testbed Vehicle (NTV) for Aeronautics Research

    Science.gov (United States)

    Nickol, Craig L.; Frederic, Peter

    2013-01-01

    A conceptual design and cost estimate for a subsonic flight research vehicle designed to support NASA's Environmentally Responsible Aviation (ERA) project goals is presented. To investigate the technical and economic feasibility of modifying an existing aircraft, a highly modified Boeing 717 was developed for maturation of technologies supporting the three ERA project goals of reduced fuel burn, noise, and emissions. This modified 717 utilizes midfuselage mounted modern high bypass ratio engines in conjunction with engine exhaust shielding structures to provide a low noise testbed. The testbed also integrates a natural laminar flow wing section and active flow control for the vertical tail. An eight year program plan was created to incrementally modify and test the vehicle, enabling the suite of technology benefits to be isolated and quantified. Based on the conceptual design and programmatic plan for this testbed vehicle, a full cost estimate of $526M was developed, representing then-year dollars at a 50% confidence level.

  5. A grounded theory como abordagem metodológica: relatos de uma experiência de campo

    Directory of Open Access Journals (Sweden)

    Marcelo de Rezende Pinto

    2012-09-01

    Full Text Available Uma vez que já é possível encontrar no Brasil alguns artigos que contemplam questões atinentes ao histórico, tipologias e principais características da grounded theory, este trabalho tem por finalidade contribuir para uma maior discussão dessa abordagem metodológica enquanto estilo de fazer pesquisa. De maneira específi ca, o trabalho tenta descrever uma experiência de campo e, principalmente, contar a saga de um pesquisador envolvido com o desafio de colocar a grounded theory em prática. Para isso, buscou-se dividir o trabalho em três partes distintas. Na primeira parte, apresentamos a grounded theory de uma maneira ampla, introduzindo alguns dos seus princípios fundamentais. Na segunda parte, descreve-se o trabalho de campo que foi realizado - nos moldes da grounded theory - com o objetivo de investigar a forma como os consumidores brasileiros oriundos das classes mais populares vivenciam suas experiências de consumo de produtos eletrônicos. Na terceira e última parte, são apresentadas algumas reflexões sobre as exigências práticas para a “operacionalização” de pesquisas comprometidas com o “espírito” da grounded theory, bem como as dúvidas, os dilemas, as difi culdades e as angústias vivenciadas ao longo de todo o processo de pesquisa contadas por quem passou por elas. ----- The Grounded Theory as Methodological Approach: reports of a field experience ----- ABSTRACT ----- As there are few articles that address issues relating to the history, types and main characteristics of grounded theory in Brazil, this paper aims to further the discussion of this methodological approach as a way of doing research. More specifically, the paper describes a field experience, and in particular the history of a researcher involved with the challenge of putting grounded theory into practice. The work is divided into three distinct parts. First we present grounded theory broadly, introducing some of its fundamental

  6. Software Testbed for Developing and Evaluating Integrated Autonomous Subsystems

    Science.gov (United States)

    Ong, James; Remolina, Emilio; Prompt, Axel; Robinson, Peter; Sweet, Adam; Nishikawa, David

    2015-01-01

    To implement fault tolerant autonomy in future space systems, it will be necessary to integrate planning, adaptive control, and state estimation subsystems. However, integrating these subsystems is difficult, time-consuming, and error-prone. This paper describes Intelliface/ADAPT, a software testbed that helps researchers develop and test alternative strategies for integrating planning, execution, and diagnosis subsystems more quickly and easily. The testbed's architecture, graphical data displays, and implementations of the integrated subsystems support easy plug and play of alternate components to support research and development in fault-tolerant control of autonomous vehicles and operations support systems. Intelliface/ADAPT controls NASA's Advanced Diagnostics and Prognostics Testbed (ADAPT), which comprises batteries, electrical loads (fans, pumps, and lights), relays, circuit breakers, invertors, and sensors. During plan execution, an experimentor can inject faults into the ADAPT testbed by tripping circuit breakers, changing fan speed settings, and closing valves to restrict fluid flow. The diagnostic subsystem, based on NASA's Hybrid Diagnosis Engine (HyDE), detects and isolates these faults to determine the new state of the plant, ADAPT. Intelliface/ADAPT then updates its model of the ADAPT system's resources and determines whether the current plan can be executed using the reduced resources. If not, the planning subsystem generates a new plan that reschedules tasks, reconfigures ADAPT, and reassigns the use of ADAPT resources as needed to work around the fault. The resource model, planning domain model, and planning goals are expressed using NASA's Action Notation Modeling Language (ANML). Parts of the ANML model are generated automatically, and other parts are constructed by hand using the Planning Model Integrated Development Environment, a visual Eclipse-based IDE that accelerates ANML model development. Because native ANML planners are currently

  7. The OTTI space experiments

    International Nuclear Information System (INIS)

    Brewer, D.A.; Clifton, K.S.; Pearson, S.D.; Barth, J.L.; LaBel, K.; Ritter, J.C.; Peden, J.; Campbell, A.; Liang, R.

    1999-01-01

    The orbiting technology tested initiative (OTTI) provides a concept for a series of space experiment platforms to be flown at 2-year interval over the next ten years. The long-term purpose of this program is to provide a convenient test-beds to simulate high radiation environments. The purposes of the first platform is to evaluate the on-orbit performance of novel, emerging, breakthrough technologies and advanced state-of-the-art devices in high radiation orbits and to provide correlations between the natural space radiation environment and the device response in the flight test-bed. This short article presents the concept of the OTTI program

  8. Adaptive Signal Processing Testbed: VME-based DSP board market survey

    Science.gov (United States)

    Ingram, Rick E.

    1992-04-01

    The Adaptive Signal Processing Testbed (ASPT) is a real-time multiprocessor system utilizing digital signal processor technology on VMEbus based printed circuit boards installed on a Sun workstation. The ASPT has specific requirements, particularly as regards to the signal excision application, with respect to interfacing with current and planned data generation equipment, processing of the data, storage to disk of final and intermediate results, and the development tools for applications development and integration into the overall EW/COM computing environment. A prototype ASPT was implemented using three VME-C-30 boards from Applied Silicon. Experience gained during the prototype development led to the conclusions that interprocessor communications capability is the most significant contributor to overall ASPT performance. In addition, the host involvement should be minimized. Boards using different processors were evaluated with respect to the ASPT system requirements, pricing, and availability. Specific recommendations based on various priorities are made as well as recommendations concerning the integration and interaction of various tools developed during the prototype implementation.

  9. M1 mirror print-through investigation and performance on the thermo-opto-mechanical testbed for the Space Interferometry Mission

    Science.gov (United States)

    Feria, V. Alfonso; Lam, Jonathan; Van Buren, Dave

    2006-06-01

    SIM PlanetQuest (SIM) is a large (9-meter baseline) space-borne optical interferometer that will determine the position and distance of stars to high accuracy. With microarcsecond measurements SIM will probe nearby stars for Earth-sized planets. To achieve this precision, SIM requires very tight manufacturing tolerances and high stability of optical components. To reduce technical risks, the SIM project developed an integrated thermal, mechanical and optical testbed (TOM3) to allow predictions of the system performance at the required high precision. The TOM3 testbed used full-scale brassboard optical components and picometer-class metrology to reach the SIM target performance levels. During the testbed integration and after one of the testbed mirrors, M1, was bonded into its mount, some surface distortion dimples that exceeded the optical specification were discovered. A detailed finite element model was used to analyze different load cases to try to determine the source of the M1 surface deformations. The same model was also used to compare with actual deformations due to varied thermal conditions on the TOM3 testbed. This paper presents the studies carried out to determine the source of the surface distortions on the M1 mirror as well as comparison and model validation during testing. This research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.

  10. Social media analytics and research testbed (SMART: Exploring spatiotemporal patterns of human dynamics with geo-targeted social media messages

    Directory of Open Access Journals (Sweden)

    Jiue-An Yang

    2016-06-01

    Full Text Available The multilevel model of meme diffusion conceptualizes how mediated messages diffuse over time and space. As a pilot application of implementing the meme diffusion, we developed the social media analytics and research testbed to monitor Twitter messages and track the diffusion of information in and across different cities and geographic regions. Social media analytics and research testbed is an online geo-targeted search and analytics tool, including an automatic data processing procedure at the backend and an interactive frontend user interface. Social media analytics and research testbed is initially designed to facilitate (1 searching and geo-locating tweet topics and terms in different cities and geographic regions; (2 filtering noise from raw data (such as removing redundant retweets and using machine learning methods to improve precision; (3 analyzing social media data from a spatiotemporal perspective; and (4 visualizing social media data in diagnostic ways (such as weekly and monthly trends, trend maps, top media, top retweets, top mentions, or top hashtags. Social media analytics and research testbed provides researchers and domain experts with a tool that can efficiently facilitate the refinement, formalization, and testing of research hypotheses or questions. Three case studies (flu outbreaks, Ebola epidemic, and marijuana legalization are introduced to illustrate how the predictions of meme diffusion can be examined and to demonstrate the potentials and key functions of social media analytics and research testbed.

  11. Benchmarking Diagnostic Algorithms on an Electrical Power System Testbed

    Science.gov (United States)

    Kurtoglu, Tolga; Narasimhan, Sriram; Poll, Scott; Garcia, David; Wright, Stephanie

    2009-01-01

    Diagnostic algorithms (DAs) are key to enabling automated health management. These algorithms are designed to detect and isolate anomalies of either a component or the whole system based on observations received from sensors. In recent years a wide range of algorithms, both model-based and data-driven, have been developed to increase autonomy and improve system reliability and affordability. However, the lack of support to perform systematic benchmarking of these algorithms continues to create barriers for effective development and deployment of diagnostic technologies. In this paper, we present our efforts to benchmark a set of DAs on a common platform using a framework that was developed to evaluate and compare various performance metrics for diagnostic technologies. The diagnosed system is an electrical power system, namely the Advanced Diagnostics and Prognostics Testbed (ADAPT) developed and located at the NASA Ames Research Center. The paper presents the fundamentals of the benchmarking framework, the ADAPT system, description of faults and data sets, the metrics used for evaluation, and an in-depth analysis of benchmarking results obtained from testing ten diagnostic algorithms on the ADAPT electrical power system testbed.

  12. The microelectronics and photonics test bed (MPTB) space, ground test and modeling experiments

    International Nuclear Information System (INIS)

    Campbell, A.

    1999-01-01

    This paper is an overview of the MPTB (microelectronics and photonics test bed) experiment, a combination of a space experiment, ground test and modeling programs looking at the response of advanced electronic and photonic technologies to the natural radiation environment of space. (author)

  13. Design and construction of a 76m long-travel laser enclosure for a space occulter testbed

    Science.gov (United States)

    Galvin, Michael; Kim, Yunjong; Kasdin, N. Jeremy; Sirbu, Dan; Vanderbei, Robert; Echeverri, Dan; Sagolla, Giuseppe; Rousing, Andreas; Balasubramanian, Kunjithapatham; Ryan, Daniel; Shaklan, Stuart; Lisman, Doug

    2016-07-01

    Princeton University is upgrading our space occulter testbed. In particular, we are lengthening it to 76m to achieve flightlike Fresnel numbers. This much longer testbed required an all-new enclosure design. In this design, we prioritized modularity and the use of commercial off-the-shelf (COTS) and semi-COTS components. Several of the technical challenges encountered included an unexpected slow beam drift and black paint selection. Herein we describe the design and construction of this long-travel laser enclosure.

  14. Autonomous power expert fault diagnostic system for Space Station Freedom electrical power system testbed

    Science.gov (United States)

    Truong, Long V.; Walters, Jerry L.; Roth, Mary Ellen; Quinn, Todd M.; Krawczonek, Walter M.

    1990-01-01

    The goal of the Autonomous Power System (APS) program is to develop and apply intelligent problem solving and control to the Space Station Freedom Electrical Power System (SSF/EPS) testbed being developed and demonstrated at NASA Lewis Research Center. The objectives of the program are to establish artificial intelligence technology paths, to craft knowledge-based tools with advanced human-operator interfaces for power systems, and to interface and integrate knowledge-based systems with conventional controllers. The Autonomous Power EXpert (APEX) portion of the APS program will integrate a knowledge-based fault diagnostic system and a power resource planner-scheduler. Then APEX will interface on-line with the SSF/EPS testbed and its Power Management Controller (PMC). The key tasks include establishing knowledge bases for system diagnostics, fault detection and isolation analysis, on-line information accessing through PMC, enhanced data management, and multiple-level, object-oriented operator displays. The first prototype of the diagnostic expert system for fault detection and isolation has been developed. The knowledge bases and the rule-based model that were developed for the Power Distribution Control Unit subsystem of the SSF/EPS testbed are described. A corresponding troubleshooting technique is also described.

  15. OPNET/Simulink Based Testbed for Disturbance Detection in the Smart Grid

    Energy Technology Data Exchange (ETDEWEB)

    Sadi, Mohammad A. H. [University of Memphis; Dasgupta, Dipankar [ORNL; Ali, Mohammad Hassan [University of Memphis; Abercrombie, Robert K [ORNL

    2015-01-01

    The important backbone of the smart grid is the cyber/information infrastructure, which is primarily used to communicate with different grid components. A smart grid is a complex cyber physical system containing a numerous and variety number of sources, devices, controllers and loads. Therefore, the smart grid is vulnerable to grid related disturbances. For such dynamic system, disturbance and intrusion detection is a paramount issue. This paper presents a Simulink and Opnet based co-simulated platform to carry out a cyber-intrusion in cyber network for modern power systems and the smart grid. The IEEE 30 bus power system model is used to demonstrate the effectiveness of the simulated testbed. The experiments were performed by disturbing the circuit breakers reclosing time through a cyber-attack. Different disturbance situations in the considered test system are considered and the results indicate the effectiveness of the proposed co-simulated scheme.

  16. Development of optical packet and circuit integrated ring network testbed.

    Science.gov (United States)

    Furukawa, Hideaki; Harai, Hiroaki; Miyazawa, Takaya; Shinada, Satoshi; Kawasaki, Wataru; Wada, Naoya

    2011-12-12

    We developed novel integrated optical packet and circuit switch-node equipment. Compared with our previous equipment, a polarization-independent 4 × 4 semiconductor optical amplifier switch subsystem, gain-controlled optical amplifiers, and one 100 Gbps optical packet transponder and seven 10 Gbps optical path transponders with 10 Gigabit Ethernet (10GbE) client-interfaces were newly installed in the present system. The switch and amplifiers can provide more stable operation without equipment adjustments for the frequent polarization-rotations and dynamic packet-rate changes of optical packets. We constructed an optical packet and circuit integrated ring network testbed consisting of two switch nodes for accelerating network development, and we demonstrated 66 km fiber transmission and switching operation of multiplexed 14-wavelength 10 Gbps optical paths and 100 Gbps optical packets encapsulating 10GbE frames. Error-free (frame error rate optical packets of various packet lengths and packet rates, and stable operation of the network testbed was confirmed. In addition, 4K uncompressed video streaming over OPS links was successfully demonstrated. © 2011 Optical Society of America

  17. Design And Ground Testing For The Expert PL4/PL5 'Natural And Roughness Induced Transition'

    Science.gov (United States)

    Masutti, Davie; Chazot, Olivier; Donelli, Raffaele; de Rosa, Donato

    2011-05-01

    Unpredicted boundary layer transition can impact dramatically the stability of the vehicle, its aerodynamic coefficients and reduce the efficiency of the thermal protection system. In this frame, ESA started the EXPERT (European eXPErimental Reentry Testbed) program to pro- vide and perform in-flight experiments in order to obtain aerothermodynamic data for the validation of numerical models and of ground-to-flight extrapolation methodologies. Considering the boundary layer transition investigation, the EXPERT vehicle is equipped with two specific payloads, PL4 and PL5, concerning respectively the study of the natural and roughness induced transition. The paper is a survey on the design process of these two in-flight experiments and it covers the major analyses and findings encountered during the development of the payloads. A large amount of transition criteria have been investigated and used to estimate either the dangerousness of the height of the distributed roughness, arising due to nose erosion, or the effectiveness of height of the isolated roughness element forcing the boundary layer transition. Supporting the PL4 design, linear stability computations and CFD analyses have been performed by CIRA on the EXPERT flight vehicle to determine the amplification factor of the boundary layer instabilities at different point of the re-entry trajectory. Ground test experiments regarding the PL5 are carried on in the Mach 6 VKI H3 Hypersonic Wind Tunnel with a Reynolds numbers ranging from 18E6/m to 26E6/m. Infrared measurements (Stanton number) and flow visualization are used on a 1/16 scaled model of the EXPERT vehicle and a flat plate to validate the Potter and Whitfield criterion as a suitable methodology for ground-to-flight extrapolation and the payload design.

  18. Analysis, modeling, and simulation (AMS) testbed development and evaluation to support dynamic mobility applications (DMA) and active transportation and demand management (ATDM) programs - evaluation summary for the San Diego testbed

    Science.gov (United States)

    2017-08-01

    The primary objective of this project is to develop multiple simulation testbeds and transportation models to evaluate the impacts of Connected Vehicle Dynamic Mobility Applications (DMA) and Active Transportation and Demand Management (ATDM) strateg...

  19. Analysis, Modeling, and Simulation (AMS) Testbed Development and Evaluation to Support Dynamic Mobility Applications (DMA) and Active Transportation and Demand Management (ATDM) Programs - Evaluation Report for the San Diego Testbed

    Science.gov (United States)

    2017-07-01

    The primary objective of this project is to develop multiple simulation testbeds and transportation models to evaluate the impacts of Connected Vehicle Dynamic Mobility Applications (DMA) and Active Transportation and Demand Management (ATDM) strateg...

  20. Saudi Deaf Students Post-Secondary Transitioning Experience: A Grounded Theory Study

    Science.gov (United States)

    Almotiri, Abdullah

    2017-01-01

    Understanding how deaf and hard-of-hearing (DHH) international students transition to post-secondary institutions is important for ensuring their academic and personal success. In this grounded theory study, five Saudi Arabian students who are DHH and enrolled at Gallaudet University were interviewed about their transition experience. Participants…

  1. Development of an Experimental Testbed for Research in Lithium-Ion Battery Management Systems

    Directory of Open Access Journals (Sweden)

    Mehdi Ferdowsi

    2013-10-01

    Full Text Available Advanced electrochemical batteries are becoming an integral part of a wide range of applications from household and commercial to smart grid, transportation, and aerospace applications. Among different battery technologies, lithium-ion (Li-ion batteries are growing more and more popular due to their high energy density, high galvanic potential, low self-discharge, low weight, and the fact that they have almost no memory effect. However, one of the main obstacles facing the widespread commercialization of Li-ion batteries is the design of reliable battery management systems (BMSs. An efficient BMS ensures electrical safety during operation, while increasing battery lifetime, capacity and thermal stability. Despite the need for extensive research in this field, the majority of research conducted on Li-ion battery packs and BMS are proprietary works conducted by manufacturers. The available literature, however, provides either general descriptions or detailed analysis of individual components of the battery system, and ignores addressing details of the overall system development. This paper addresses the development of an experimental research testbed for studying Li-ion batteries and their BMS design. The testbed can be configured in a variety of cell and pack architectures, allowing for a wide range of BMS monitoring, diagnostics, and control technologies to be tested and analyzed. General considerations that should be taken into account while designing Li-ion battery systems are reviewed and different technologies and challenges commonly encountered in Li-ion battery systems are investigated. This testbed facilitates future development of more practical and improved BMS technologies with the aim of increasing the safety, reliability, and efficiency of existing Li-ion battery systems. Experimental results of initial tests performed on the system are used to demonstrate some of the capabilities of the developed research testbed. To the authors

  2. Diffusion from a Ground Level Point Source Experiment with Thermoluminescence Dosimeters and Kr 85 as Tracer Substance

    Energy Technology Data Exchange (ETDEWEB)

    Gyllander, Ch; Hollman, S; Widemo, U

    1969-04-15

    Within the framework of the IRIS-project (Iodine Research in Safety Project) an experiment to study diffusion at near-ground level was carried out on 19 December 1967 using {sup 85}Kr as the tracer element. The object of the experiment was a) to test the method using |3-sensitive thermoluminescence dosimeters under actual field conditions. b) to study the initial dilution from a ground level point source. The test area chosen was the Tranvik valley just south of Trobbofjaerden, an inland bay of the Baltic. Dose distributions have been studied at two sections, 50 and 200 m respectively, from the release point. At each level various dispersion parameters have been experimentally determined and their conformity to normal distribution have been calculated. Dilution factors valid for the centre of the plume are related to the values reported in the literature. The experiment was made under ideal weather conditions above snow-free ground. Results of the next experiment, a point release at ground level from a building at Studsvik, are expected to yield valuable information concerning the effect of buildings on the diffusion pattern.

  3. Diffusion from a Ground Level Point Source Experiment with Thermoluminescence Dosimeters and Kr 85 as Tracer Substance

    International Nuclear Information System (INIS)

    Gyllander, Ch.; Hollman, S.; Widemo, U.

    1969-04-01

    Within the framework of the IRIS-project (Iodine Research in Safety Project) an experiment to study diffusion at near-ground level was carried out on 19 December 1967 using 85 Kr as the tracer element. The object of the experiment was a) to test the method using |3-sensitive thermoluminescence dosimeters under actual field conditions. b) to study the initial dilution from a ground level point source. The test area chosen was the Tranvik valley just south of Trobbofjaerden, an inland bay of the Baltic. Dose distributions have been studied at two sections, 50 and 200 m respectively, from the release point. At each level various dispersion parameters have been experimentally determined and their conformity to normal distribution have been calculated. Dilution factors valid for the centre of the plume are related to the values reported in the literature. The experiment was made under ideal weather conditions above snow-free ground. Results of the next experiment, a point release at ground level from a building at Studsvik, are expected to yield valuable information concerning the effect of buildings on the diffusion pattern

  4. Improvement in operating incident experience at the Savannah River Burial Ground

    International Nuclear Information System (INIS)

    Cornman, W.R.

    1979-01-01

    Low-level radioactive wastes generated at the Savannah River Plant and Laboratory are stored at the Savannah River burial ground. These wastes have accumulated from >20 years of reprocessing nuclear fuels and materials for defense programs at the Savannah River Plant. Burial in earthen trenches and aboveground storage for transuranic materials are the principal modes of storage. The infrequent operating incidents that have occurred during the 20-year period have been analyzed. The incidents can be categorized as those causing airborne contamination, waterborne contamination, or vegetation contamination through penetration of plant roots into contaminated soil. Contamination was generally confined to the immediate area of the burial ground. Several incidents occurred because of unintentional burial or exhumation of material. The frequency of operating incidents decreased with operating experience of the burial ground, averaging only about two incidents per year during the last six years of operation

  5. Successful range-expanding plants experience less above-ground and below-ground enemy impact.

    Science.gov (United States)

    Engelkes, Tim; Morriën, Elly; Verhoeven, Koen J F; Bezemer, T Martijn; Biere, Arjen; Harvey, Jeffrey A; McIntyre, Lauren M; Tamis, Wil L M; van der Putten, Wim H

    2008-12-18

    Many species are currently moving to higher latitudes and altitudes. However, little is known about the factors that influence the future performance of range-expanding species in their new habitats. Here we show that range-expanding plant species from a riverine area were better defended against shoot and root enemies than were related native plant species growing in the same area. We grew fifteen plant species with and without non-coevolved polyphagous locusts and cosmopolitan, polyphagous aphids. Contrary to our expectations, the locusts performed more poorly on the range-expanding plant species than on the congeneric native plant species, whereas the aphids showed no difference. The shoot herbivores reduced the biomass of the native plants more than they did that of the congeneric range expanders. Also, the range-expanding plants developed fewer pathogenic effects in their root-zone soil than did the related native species. Current predictions forecast biodiversity loss due to limitations in the ability of species to adjust to climate warming conditions in their range. Our results strongly suggest that the plants that shift ranges towards higher latitudes and altitudes may include potential invaders, as the successful range expanders may experience less control by above-ground or below-ground enemies than the natives.

  6. Genetic Algorithm Phase Retrieval for the Systematic Image-Based Optical Alignment Testbed

    Science.gov (United States)

    Taylor, Jaime; Rakoczy, John; Steincamp, James

    2003-01-01

    Phase retrieval requires calculation of the real-valued phase of the pupil fimction from the image intensity distribution and characteristics of an optical system. Genetic 'algorithms were used to solve two one-dimensional phase retrieval problem. A GA successfully estimated the coefficients of a polynomial expansion of the phase when the number of coefficients was correctly specified. A GA also successfully estimated the multiple p h e s of a segmented optical system analogous to the seven-mirror Systematic Image-Based Optical Alignment (SIBOA) testbed located at NASA s Marshall Space Flight Center. The SIBOA testbed was developed to investigate phase retrieval techniques. Tiphilt and piston motions of the mirrors accomplish phase corrections. A constant phase over each mirror can be achieved by an independent tip/tilt correction: the phase Conection term can then be factored out of the Discrete Fourier Tranform (DFT), greatly reducing computations.

  7. Design and Prototyping of a Satellite Antenna Slew Testbed

    Science.gov (United States)

    2013-12-01

    beers and kind advice gave me a family away from home. To my familia here in the Bay Area; their constant support, understanding and surprise...Encoder Cable Maxon 275934 2 CAB 29 EPOS Power Cable Maxon 275829 2 CAB 30 Misc Hardware** NPS 30 - - Bill of Materials 35 closely match the actual ...computed trajectory. The position and velocity results were then implemented on the testbed motors for comparison of actual versus commanded values

  8. Recovery as a Lived Experience Discipline: A Grounded Theory Study.

    Science.gov (United States)

    Byrne, Louise; Happell, Brenda; Reid-Searl, Kerry

    2015-01-01

    Recovery is government mandated and a core facet of mental health reform. However, Recovery implementation in this country (Australia) has been inhibited by a lack of education of, and understanding from, clinicians. A grounded theory study was undertaken to explore the potential and existing role of lived experience practitioners in assisting meaningful implementations of Recovery within the Australian mental health sector. In-depth interviews were conducted with 13 people employed to work from a lived experience perspective. The findings suggest participants have experienced and observed significant barriers to the implementation of Recovery-focused practice while operating in lived experience roles. Three main issues emerged: (1) Recovery co-opted, (2) Recovery uptake, and (3) Recovery denial. For a genuine Recovery-focused mental health system to be developed, lived experience practitioners must be enabled to take their role as Recovery experts and leaders. Lived experience practitioners are the logical leaders of Recovery implementation due to their own internal experience and understandings of Recovery and the wider lived experience movement's development and championing of the concepts.

  9. Design of a low-power testbed for Wireless Sensor Networks and verification

    NARCIS (Netherlands)

    van Hoesel, L.F.W.; Dulman, S.O.; Havinga, Paul J.M.; Kip, Harry J.

    In this document the design considerations and component choices of a testbed prototype device for wireless sensor networks will be discussed. These devices must be able to monitor their physical environment, process data and assist other nodes in forwarding sensor readings. For these tasks, five

  10. TESTING THE APODIZED PUPIL LYOT CORONAGRAPH ON THE LABORATORY FOR ADAPTIVE OPTICS EXTREME ADAPTIVE OPTICS TESTBED

    International Nuclear Information System (INIS)

    Thomas, Sandrine J.; Dillon, Daren; Gavel, Donald; Soummer, Remi; Macintosh, Bruce; Sivaramakrishnan, Anand

    2011-01-01

    We present testbed results of the Apodized Pupil Lyot Coronagraph (APLC) at the Laboratory for Adaptive Optics (LAO). These results are part of the validation and tests of the coronagraph and of the Extreme Adaptive Optics (ExAO) for the Gemini Planet Imager (GPI). The apodizer component is manufactured with a halftone technique using black chrome microdots on glass. Testing this APLC (like any other coronagraph) requires extremely good wavefront correction, which is obtained to the 1 nm rms level using the microelectricalmechanical systems (MEMS) technology, on the ExAO visible testbed of the LAO at the University of Santa Cruz. We used an APLC coronagraph without central obstruction, both with a reference super-polished flat mirror and with the MEMS to obtain one of the first images of a dark zone in a coronagraphic image with classical adaptive optics using a MEMS deformable mirror (without involving dark hole algorithms). This was done as a complementary test to the GPI coronagraph testbed at American Museum of Natural History, which studied the coronagraph itself without wavefront correction. Because we needed a full aperture, the coronagraph design is very different from the GPI design. We also tested a coronagraph with central obstruction similar to that of GPI. We investigated the performance of the APLC coronagraph and more particularly the effect of the apodizer profile accuracy on the contrast. Finally, we compared the resulting contrast to predictions made with a wavefront propagation model of the testbed to understand the effects of phase and amplitude errors on the final contrast.

  11. Testbed model and data assimilation for ARM

    International Nuclear Information System (INIS)

    Louis, J.F.

    1992-01-01

    The objectives of this contract are to further develop and test the ALFA (AER Local Forecast and Assimilation) model originally designed at AER for local weather prediction and apply it to three distinct but related purposes in connection with the Atmospheric Radiation Measurement (ARM) program: (a) to provide a testbed that simulates a global climate model in order to facilitate the development and testing of new cloud parametrizations and radiation models; (b) to assimilate the ARM data continuously at the scale of a climate model, using the adjoint method, thus providing the initial conditions and verification data for testing parameumtions; (c) to study the sensitivity of a radiation scheme to cloud parameters, again using the adjoint method, thus demonstrating the usefulness of the testbed model. The data assimilation will use a variational technique that minimizes the difference between the model results and the observation during the analysis period. The adjoint model is used to compute the gradient of a measure of the model errors with respect to nudging terms that are added to the equations to force the model output closer to the data. The radiation scheme that will be included in the basic ALFA model makes use of a gen two-stream approximation, and is designed for vertically inhonogeneous, multiple-scattering atmospheres. The sensitivity of this model to the definition of cloud parameters will be studied. The adjoint technique will also be used to compute the sensitivities. This project is designed to provide the Science Team members with the appropriate tools and modeling environment for proper testing and tuning of new radiation models and cloud parametrization schemes

  12. A commercial space technology testbed on ISS

    Science.gov (United States)

    Boyle, David R.

    2000-01-01

    There is a significant and growing commercial market for new, more capable communications and remote sensing satellites. Competition in this market strongly motivates satellite manufacturers and spacecraft component developers to test and demonstrate new space hardware in a realistic environment. External attach points on the International Space Station allow it to function uniquely as a space technology testbed to satisfy this market need. However, space industry officials have identified three critical barriers to their commercial use of the ISS: unpredictable access, cost risk, and schedule uncertainty. Appropriate NASA policy initiatives and business/technical assistance for industry from the Commercial Space Center for Engineering can overcome these barriers. .

  13. Testbed for a LiFi system integrated in streetlights

    OpenAIRE

    Monzón Baeza, Victor; Sánchez Fernández, Matilde Pilar; García-Armada, Ana; Royo, A.

    2015-01-01

    Proceeding at: 2015 European Conference on Networks and Communications (EuCNC) took place June 29 - July 2 in Paris, France. In this paper, a functional LiFi real-time testbed implemented on FPGAs is presented. The setup evaluates the performance of our design in a downlink scenario where the transmitter is embedded on the streetlights and a mobile phone’s camera is used as receiver, therefore achieving the goal of lighting and communicating simultaneously. To validate the ...

  14. Analysis, Modeling, and Simulation (AMS) Testbed Development and Evaluation to Support Dynamic Mobility Applications (DMA) and Active Transportation and Demand Management (ATDM) Programs : Evaluation Report for the San Diego Testbed : Draft Report.

    Science.gov (United States)

    2017-07-01

    The primary objective of this project is to develop multiple simulation testbeds and transportation models to evaluate the impacts of Connected Vehicle Dynamic Mobility Applications (DMA) and Active Transportation and Demand Management (ATDM) strateg...

  15. PlanetLab Europe as Geographically-Distributed Testbed for Software Development and Evaluation

    Directory of Open Access Journals (Sweden)

    Dan Komosny

    2015-01-01

    Full Text Available In this paper, we analyse the use of PlanetLab Europe for development and evaluation of geographically-oriented Internet services. PlanetLab is a global research network with the main purpose to support development of new Internet services and protocols. PlanetLab is divided into several branches; one of them is PlanetLab Europe. PlanetLab Europe consists of about 350 nodes at 150 geographically different sites. The nodes are accessible by remote login, and the users can run their software on the nodes. In the paper, we study the PlanetLab's properties that are significant for its use as a geographically distributed testbed. This includes node position accuracy, services availability and stability. We find a considerable number of location inaccuracies and a number of services that cannot be considered as reliable. Based on the results we propose a simple approach to nodes selection in testbeds for geographically-oriented Internet services development and evaluation.

  16. Sensing across large-scale cognitive radio networks: Data processing, algorithms, and testbed for wireless tomography and moving target tracking

    Science.gov (United States)

    Bonior, Jason David

    As the use of wireless devices has become more widespread so has the potential for utilizing wireless networks for remote sensing applications. Regular wireless communication devices are not typically designed for remote sensing. Remote sensing techniques must be carefully tailored to the capabilities of these networks before they can be applied. Experimental verification of these techniques and algorithms requires robust yet flexible testbeds. In this dissertation, two experimental testbeds for the advancement of research into sensing across large-scale cognitive radio networks are presented. System architectures, implementations, capabilities, experimental verification, and performance are discussed. One testbed is designed for the collection of scattering data to be used in RF and wireless tomography research. This system is used to collect full complex scattering data using a vector network analyzer (VNA) and amplitude-only data using non-synchronous software-defined radios (SDRs). Collected data is used to experimentally validate a technique for phase reconstruction using semidefinite relaxation and demonstrate the feasibility of wireless tomography. The second testbed is a SDR network for the collection of experimental data. The development of tools for network maintenance and data collection is presented and discussed. A novel recursive weighted centroid algorithm for device-free target localization using the variance of received signal strength for wireless links is proposed. The signal variance resulting from a moving target is modeled as having contours related to Cassini ovals. This model is used to formulate recursive weights which reduce the influence of wireless links that are farther from the target location estimate. The algorithm and its implementation on this testbed are presented and experimental results discussed.

  17. Vaccination learning experiences of nursing students: a grounded theory study.

    Science.gov (United States)

    Ildarabadi, Eshagh; Karimi Moonaghi, Hossein; Heydari, Abbas; Taghipour, Ali; Abdollahimohammad, Abdolghani

    2015-01-01

    This study aimed to explore the experiences of nursing students being trained to perform vaccinations. The grounded theory method was applied to gather information through semi-structured interviews. The participants included 14 undergraduate nursing students in their fifth and eighth semesters of study in a nursing school in Iran. The information was analyzed according to Strauss and Corbin's method of grounded theory. A core category of experiential learning was identified, and the following eight subcategories were extracted: students' enthusiasm, vaccination sensitivity, stress, proper educational environment, absence of prerequisites, students' responsibility for learning, providing services, and learning outcomes. The vaccination training of nursing students was found to be in an acceptable state. However, some barriers to effective learning were identified. As such, the results of this study may provide empirical support for attempts to reform vaccination education by removing these barriers.

  18. Accelerating Innovation that Enhances Resource Recovery in the Wastewater Sector: Advancing a National Testbed Network.

    Science.gov (United States)

    Mihelcic, James R; Ren, Zhiyong Jason; Cornejo, Pablo K; Fisher, Aaron; Simon, A J; Snyder, Seth W; Zhang, Qiong; Rosso, Diego; Huggins, Tyler M; Cooper, William; Moeller, Jeff; Rose, Bob; Schottel, Brandi L; Turgeon, Jason

    2017-07-18

    This Feature examines significant challenges and opportunities to spur innovation and accelerate adoption of reliable technologies that enhance integrated resource recovery in the wastewater sector through the creation of a national testbed network. The network is a virtual entity that connects appropriate physical testing facilities, and other components needed for a testbed network, with researchers, investors, technology providers, utilities, regulators, and other stakeholders to accelerate the adoption of innovative technologies and processes that are needed for the water resource recovery facility of the future. Here we summarize and extract key issues and developments, to provide a strategy for the wastewater sector to accelerate a path forward that leads to new sustainable water infrastructures.

  19. An Approach for Smart Antenna Testbed

    Science.gov (United States)

    Kawitkar, R. S.; Wakde, D. G.

    2003-07-01

    The use of wireless, mobile, personal communications services are expanding rapidly. Adaptive or "Smart" antenna arrays can increase channel capacity through spatial division. Adaptive antennas can also track mobile users, improving both signal range and quality. For these reasons, smart antenna systems have attracted widespread interest in the telecommunications industry for applications to third generation wireless systems.This paper aims to design and develop an advanced antennas testbed to serve as a common reference for testing adaptive antenna arrays and signal combining algorithms, as well as complete systems. A flexible suite of off line processing software should be written using matlab to perform system calibration, test bed initialization, data acquisition control, data storage/transfer, off line signal processing and analysis and graph plotting. The goal of this paper is to develop low complexity smart antenna structures for 3G systems. The emphasis will be laid on ease of implementation in a multichannel / multi-user environment. A smart antenna test bed will be developed, and various state-of-the-art DSP structures and algorithms will be investigated.Facing the soaring demand for mobile communications, the use of smart antenna arrays in mobile communications systems to exploit spatial diversity to further improve spectral efficiency has recently received considerable attention. Basically, a smart antenna array comprises a number of antenna elements combined via a beamforming network (amplitude and phase control network). Some of the benefits that can be achieved by using SAS (Smart Antenna System) include lower mobile terminal power consumption, range extension, ISI reduction, higher data rate support, and ease of integration into the existing base station system. In terms of economic benefits, adaptive antenna systems employed at base station, though increases the per base station cost, can increase coverage area of each cell site, thereby reducing

  20. Ground-Laboratory to In-Space Atomic Oxygen Correlation for the Polymer Erosion and Contamination Experiment (PEACE) Polymers

    Science.gov (United States)

    Stambler, Arielle H.; Inoshita, Karen E.; Roberts, Lily M.; Barbagallo, Claire E.; deGroh, Kim K.; Banks, Bruce A.

    2011-01-01

    The Materials International Space Station Experiment 2 (MISSE 2) Polymer Erosion and Contamination Experiment (PEACE) polymers were exposed to the environment of low Earth orbit (LEO) for 3.95 years from 2001 to 2005. There were 41 different PEACE polymers, which were flown on the exterior of the International Space Station (ISS) in order to determine their atomic oxygen erosion yields. In LEO, atomic oxygen is an environmental durability threat, particularly for long duration mission exposures. Although spaceflight experiments, such as the MISSE 2 PEACE experiment, are ideal for determining LEO environmental durability of spacecraft materials, ground-laboratory testing is often relied upon for durability evaluation and prediction. Unfortunately, significant differences exist between LEO atomic oxygen exposure and atomic oxygen exposure in ground-laboratory facilities. These differences include variations in species, energies, thermal exposures and radiation exposures, all of which may result in different reactions and erosion rates. In an effort to improve the accuracy of ground-based durability testing, ground-laboratory to in-space atomic oxygen correlation experiments have been conducted. In these tests, the atomic oxygen erosion yields of the PEACE polymers were determined relative to Kapton H using a radio-frequency (RF) plasma asher (operated on air). The asher erosion yields were compared to the MISSE 2 PEACE erosion yields to determine the correlation between erosion rates in the two environments. This paper provides a summary of the MISSE 2 PEACE experiment; it reviews the specific polymers tested as well as the techniques used to determine erosion yield in the asher, and it provides a correlation between the space and ground laboratory erosion yield values. Using the PEACE polymers asher to in-space erosion yield ratios will allow more accurate in-space materials performance predictions to be made based on plasma asher durability evaluation.

  1. A Testbed to Evaluate the FIWARE-Based IoT Platform in the Domain of Precision Agriculture

    Science.gov (United States)

    Martínez, Ramón; Pastor, Juan Ángel; Álvarez, Bárbara; Iborra, Andrés

    2016-01-01

    Wireless sensor networks (WSNs) represent one of the most promising technologies for precision farming. Over the next few years, a significant increase in the use of such systems on commercial farms is expected. WSNs present a number of problems, regarding scalability, interoperability, communications, connectivity with databases and data processing. Different Internet of Things middleware is appearing to overcome these challenges. This paper checks whether one of these middleware, FIWARE, is suitable for the development of agricultural applications. To the authors’ knowledge, there are no works that show how to use FIWARE in precision agriculture and study its appropriateness, its scalability and its efficiency for this kind of applications. To do this, a testbed has been designed and implemented to simulate different deployments and load conditions. The testbed is a typical FIWARE application, complete, yet simple and comprehensible enough to show the main features and components of FIWARE, as well as the complexity of using this technology. Although the testbed has been deployed in a laboratory environment, its design is based on the analysis of an Internet of Things use case scenario in the domain of precision agriculture. PMID:27886091

  2. Developing the science product algorithm testbed for Chinese next-generation geostationary meteorological satellites: Fengyun-4 series

    Science.gov (United States)

    Min, Min; Wu, Chunqiang; Li, Chuan; Liu, Hui; Xu, Na; Wu, Xiao; Chen, Lin; Wang, Fu; Sun, Fenglin; Qin, Danyu; Wang, Xi; Li, Bo; Zheng, Zhaojun; Cao, Guangzhen; Dong, Lixin

    2017-08-01

    Fengyun-4A (FY-4A), the first of the Chinese next-generation geostationary meteorological satellites, launched in 2016, offers several advances over the FY-2: more spectral bands, faster imaging, and infrared hyperspectral measurements. To support the major objective of developing the prototypes of FY-4 science algorithms, two science product algorithm testbeds for imagers and sounders have been developed by the scientists in the FY-4 Algorithm Working Group (AWG). Both testbeds, written in FORTRAN and C programming languages for Linux or UNIX systems, have been tested successfully by using Intel/g compilers. Some important FY-4 science products, including cloud mask, cloud properties, and temperature profiles, have been retrieved successfully through using a proxy imager, Himawari-8/Advanced Himawari Imager (AHI), and sounder data, obtained from the Atmospheric InfraRed Sounder, thus demonstrating their robustness. In addition, in early 2016, the FY-4 AWG was developed based on the imager testbed—a near real-time processing system for Himawari-8/AHI data for use by Chinese weather forecasters. Consequently, robust and flexible science product algorithm testbeds have provided essential and productive tools for popularizing FY-4 data and developing substantial improvements in FY-4 products.

  3. Development and experimentation of an eye/brain/task testbed

    Science.gov (United States)

    Harrington, Nora; Villarreal, James

    1987-01-01

    The principal objective is to develop a laboratory testbed that will provide a unique capability to elicit, control, record, and analyze the relationship of operator task loading, operator eye movement, and operator brain wave data in a computer system environment. The ramifications of an integrated eye/brain monitor to the man machine interface are staggering. The success of such a system would benefit users of space and defense, paraplegics, and the monitoring of boring screens (nuclear power plants, air defense, etc.)

  4. Application experiences with the Globus toolkit.

    Energy Technology Data Exchange (ETDEWEB)

    Brunett, S.

    1998-06-09

    The Globus grid toolkit is a collection of software components designed to support the development of applications for high-performance distributed computing environments, or ''computational grids'' [14]. The Globus toolkit is an implementation of a ''bag of services'' architecture, which provides application and tool developers not with a monolithic system but rather with a set of stand-alone services. Each Globus component provides a basic service, such as authentication, resource allocation, information, communication, fault detection, and remote data access. Different applications and tools can combine these services in different ways to construct ''grid-enabled'' systems. The Globus toolkit has been used to construct the Globus Ubiquitous Supercomputing Testbed, or GUSTO: a large-scale testbed spanning 20 sites and included over 4000 compute nodes for a total compute power of over 2 TFLOPS. Over the past six months, we and others have used this testbed to conduct a variety of application experiments, including multi-user collaborative environments (tele-immersion), computational steering, distributed supercomputing, and high throughput computing. The goal of this paper is to review what has been learned from these experiments regarding the effectiveness of the toolkit approach. To this end, we describe two of the application experiments in detail, noting what worked well and what worked less well. The two applications are a distributed supercomputing application, SF-Express, in which multiple supercomputers are harnessed to perform large distributed interactive simulations; and a tele-immersion application, CAVERNsoft, in which the focus is on connecting multiple people to a distributed simulated world.

  5. Attitude determination for small satellites using GPS signal-to-noise ratio

    Science.gov (United States)

    Peters, Daniel

    An embedded system for GPS-based attitude determination (AD) using signal-to-noise (SNR) measurements was developed for CubeSat applications. The design serves as an evaluation testbed for conducting ground based experiments using various computational methods and antenna types to determine the optimum AD accuracy. Raw GPS data is also stored to non-volatile memory for downloading and post analysis. Two low-power microcontrollers are used for processing and to display information on a graphic screen for real-time performance evaluations. A new parallel inter-processor communication protocol was developed that is faster and uses less power than existing standard protocols. A shorted annular patch (SAP) antenna was fabricated for the initial ground-based AD experiments with the testbed. Static AD estimations with RMS errors in the range of 2.5° to 4.8° were achieved over a range of off-zenith attitudes.

  6. The University of Canberra quantum key distribution testbed

    International Nuclear Information System (INIS)

    Ganeshkumar, G.; Edwards, P.J.; Cheung, W.N.; Barbopoulos, L.O.; Pham, H.; Hazel, J.C.

    1999-01-01

    Full text: We describe the design, operation and preliminary results obtained from a quantum key distribution (QKD) testbed constructed at the University of Canberra. Quantum cryptographic systems use shared secret keys exchanged in the form of sequences of polarisation coded or phase encoded single photons transmitted over an optical communications channel. Secrecy of this quantum key rests upon fundamental laws of quantum physics: measurements of linear or circular photon polarisation states introduce noise into the conjugate variable and so reveal eavesdropping. In its initial realisation reported here, pulsed light from a 650nm laser diode is attenuated by a factor of 10 6 , plane-polarised and then transmitted through a birefringent liquid crystal modulator (LCM) to a polarisation sensitive single photon receiver. This transmitted key sequence consists of a 1 kHz train of weak coherent 100ns wide light pulses, polarisation coded according to the BB84 protocol. Each pulse is randomly assigned one of four polarisation states (two orthogonal linear and two orthogonal circular) by computer PCA operated by the sender ('Alice'). This quaternary polarisation shift keyed photon stream is detected by the receiver ('Bob') whose computer (PCB) randomly chooses either a linear or a circular polarisation basis. Computer PCB is also used for final key selection, authentication, privacy amplification and eavesdropping. We briefly discuss the realisation of a mesoscopic single photon QKD source and the use of the testbed to simulate a global quantum key distribution system using earth satellites. Copyright (1999) Australian Optical Society

  7. Vacuum Nuller Testbed Performance, Characterization and Null Control

    Science.gov (United States)

    Lyon, R. G.; Clampin, M.; Petrone, P.; Mallik, U.; Madison, T.; Bolcar, M.; Noecker, C.; Kendrick, S.; Helmbrecht, M. A.

    2011-01-01

    The Visible Nulling Coronagraph (VNC) can detect and characterize exoplanets with filled, segmented and sparse aperture telescopes, thereby spanning the choice of future internal coronagraph exoplanet missions. NASA/Goddard Space Flight Center (GSFC) has developed a Vacuum Nuller Testbed (VNT) to advance this approach, and assess and advance technologies needed to realize a VNC as a flight instrument. The VNT is an ultra-stable testbed operating at 15 Hz in vacuum. It consists of a MachZehnder nulling interferometer; modified with a "W" configuration to accommodate a hexpacked MEMS based deformable mirror (DM), coherent fiber bundle and achromatic phase shifters. The 2-output channels are imaged with a vacuum photon counting camera and conventional camera. Error-sensing and feedback to DM and delay line with control algorithms are implemented in a real-time architecture. The inherent advantage of the VNC is that it is its own interferometer and directly controls its errors by exploiting images from bright and dark channels simultaneously. Conservation of energy requires the sum total of the photon counts be conserved independent of the VNC state. Thus sensing and control bandwidth is limited by the target stars throughput, with the net effect that the higher bandwidth offloads stressing stability tolerances within the telescope. We report our recent progress with the VNT towards achieving an incremental sequence of contrast milestones of 10(exp 8) , 10(exp 9) and 10(exp 10) respectively at inner working angles approaching 2A/D. Discussed will be the optics, lab results, technologies, and null control. Shown will be evidence that the milestones have been achieved.

  8. The CMS Integration Grid Testbed

    CERN Document Server

    Graham, G E; Aziz, Shafqat; Bauerdick, L.A.T.; Ernst, Michael; Kaiser, Joseph; Ratnikova, Natalia; Wenzel, Hans; Wu, Yu-jun; Aslakson, Erik; Bunn, Julian; Iqbal, Saima; Legrand, Iosif; Newman, Harvey; Singh, Suresh; Steenberg, Conrad; Branson, James; Fisk, Ian; Letts, James; Arbree, Adam; Avery, Paul; Bourilkov, Dimitri; Cavanaugh, Richard; Rodriguez, Jorge Luis; Kategari, Suchindra; Couvares, Peter; DeSmet, Alan; Livny, Miron; Roy, Alain; Tannenbaum, Todd; Graham, Gregory E.; Aziz, Shafqat; Ernst, Michael; Kaiser, Joseph; Ratnikova, Natalia; Wenzel, Hans; Wu, Yujun; Aslakson, Erik; Bunn, Julian; Iqbal, Saima; Legrand, Iosif; Newman, Harvey; Singh, Suresh; Steenberg, Conrad; Branson, James; Fisk, Ian; Letts, James; Arbree, Adam; Avery, Paul; Bourilkov, Dimitri; Cavanaugh, Richard; Rodriguez, Jorge; Kategari, Suchindra; Couvares, Peter; Smet, Alan De; Livny, Miron; Roy, Alain; Tannenbaum, Todd

    2003-01-01

    The CMS Integration Grid Testbed (IGT) comprises USCMS Tier-1 and Tier-2 hardware at the following sites: the California Institute of Technology, Fermi National Accelerator Laboratory, the University of California at San Diego, and the University of Florida at Gainesville. The IGT runs jobs using the Globus Toolkit with a DAGMan and Condor-G front end. The virtual organization (VO) is managed using VO management scripts from the European Data Grid (EDG). Gridwide monitoring is accomplished using local tools such as Ganglia interfaced into the Globus Metadata Directory Service (MDS) and the agent based Mona Lisa. Domain specific software is packaged and installed using the Distrib ution After Release (DAR) tool of CMS, while middleware under the auspices of the Virtual Data Toolkit (VDT) is distributed using Pacman. During a continuo us two month span in Fall of 2002, over 1 million official CMS GEANT based Monte Carlo events were generated and returned to CERN for analysis while being demonstrated at SC2002. ...

  9. Jung's equation of the ground of being with the ground of psyche.

    Science.gov (United States)

    Dourley, John

    2011-09-01

    The paper amplifies Jung's psychology of ground associated with the culmination of the alchemical process in the unus mundus. It argues that Jung and Dorn identify the experience of the ground with the experience of divinity as the common originary source of individual and totality. It notes the monistic and pantheistic implications of the experience and goes on to amplify the experience through Eckhart's mediaeval mysticism of ground and Paul Tillich's modern philosophical/theological understanding of ground. It concludes that the Jung/Dorn psychological understanding of ground supersedes monotheistic consciousness. Their vision supports the emergence of a societal myth based on the identification of the ground as the source of all divinities and faith in them. This source currently urges a mythic consciousness that would surpass its past and current concretions and so alleviate the threat that monotheistic consciousness in any domain now poses to human survival. © 2011, The Society of Analytical Psychology.

  10. Competition-strength-dependent ground suppression in figure-ground perception.

    Science.gov (United States)

    Salvagio, Elizabeth; Cacciamani, Laura; Peterson, Mary A

    2012-07-01

    Figure-ground segregation is modeled as inhibitory competition between objects that might be perceived on opposite sides of borders. The winner is the figure; the loser is suppressed, and its location is perceived as shapeless ground. Evidence of ground suppression would support inhibitory competition models and would contribute to explaining why grounds are shapeless near borders shared with figures, yet such evidence is scarce. We manipulated whether competition from potential objects on the ground side of figures was high (i.e., portions of familiar objects were potentially present there) or low (novel objects were potentially present). We predicted that greater competition would produce more ground suppression. The results of two experiments in which suppression was assessed via judgments of the orientation of target bars confirmed this prediction; a third experiment showed that ground suppression is short-lived. Our findings support inhibitory competition models of figure assignment, in particular, and models of visual perception entailing feedback, in general.

  11. Cooperating expert systems for Space Station - Power/thermal subsystem testbeds

    Science.gov (United States)

    Wong, Carla M.; Weeks, David J.; Sundberg, Gale R.; Healey, Kathleen L.; Dominick, Jeffrey S.

    1988-01-01

    The Systems Autonomy Demonstration Project (SADP) is a NASA-sponsored series of increasingly complex demonstrations to show the benefits of integrating knowledge-based systems with conventional process control in real-time, real-world problem domains that can facilitate the operations and availability of major Space Station distributed systems. This paper describes the system design, objectives, approaches, and status of each of the testbed knowledge-based systems. Simplified schematics of the systems are shown.

  12. Establishment of a sensor testbed at NIST for plant productivity monitoring

    Science.gov (United States)

    Allen, D. W.; Hutyra, L.; Reinmann, A.; Trlica, A.; Marrs, J.; Jones, T.; Whetstone, J. R.; Logan, B.; Reblin, J.

    2017-12-01

    Accurate assessments of biogenic carbon fluxes is challenging. Correlating optical signatures to plant activity allows for monitoring large regions. New methods, including solar-induced fluorescence (SIF), promise to provide more timely and accurate estimate of plant activity, but we are still developing a full understanding of the mechanistic leakage between plant assimilation of carbon and SIF. We have initiated a testbed to facilitate the evaluation of sensors and methods for remote monitoring of plant activity at the NIST headquarters. The test bed utilizes a forested area of mature trees in a mixed urban environment. A 1 hectare plot within the 26 hectare forest has been instrumented for ecophysiological measurements with an edge (100 m long) that is persistently monitored with multimodal optical sensors (SIF spectrometers, hyperspectral imagers, thermal infrared imaging, and lidar). This biological testbed has the advantage of direct access to the national scales maintained by NIST of measurements related to both the physical and optical measurements of interest. We offer a description of the test site, the sensors, and preliminary results from the first season of observations for ecological, physiological, and remote sensing based estimates of ecosystem productivity.

  13. Analysis on temperature field and flow field of reactor core barrel openings for China experiment fast reactor

    International Nuclear Information System (INIS)

    Zhang Yabo; Yang Hongyi

    2008-01-01

    The paper gives analysis of the temperature and flow field around openings by software CFX, and figures out the flow direction around openings under CEFR normal condition. The calculation result is consistent with the test result of CAPX (the test-bed of decay heat removal system) and ground for the safety analysis later. (authors)

  14. Development of Research Reactor Simulator and Its Application to Dynamic Test-bed

    International Nuclear Information System (INIS)

    Kwon, Kee Choon; Park, Jae Chang; Lee, Seung Wook; Bang, Dane; Bae, Sung Won

    2014-01-01

    We developed HANARO and the Jordan Research and Training Reactor (JRTR) real-time simulator for operating staff training. The main purpose of this simulator is operator training, but we modified this simulator as a dynamic test-bed to test the reactor regulating system in HANARO or JRTR before installation. The simulator configuration is divided into hardware and software. The simulator hardware consists of a host computer, 6 operator stations, a network switch, and a large display panel. The simulator software is divided into three major parts: a mathematical modeling module, which executes the plant dynamic modeling program in real-time, an instructor station module that manages user instructions, and a human machine interface (HMI) module. The developed research reactors are installed in the Korea Atomic Energy Research Institute nuclear training center for reactor operator training. To use the simulator as a dynamic test-bed, the reactor regulating system modeling software of the simulator was replaced by a hardware controller and the simulator and target controller were interfaced with a hard-wired and network-based interface

  15. Development of Research Reactor Simulator and Its Application to Dynamic Test-bed

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Kee Choon; Park, Jae Chang; Lee, Seung Wook; Bang, Dane; Bae, Sung Won [KAERI, Daejeon (Korea, Republic of)

    2014-08-15

    We developed HANARO and the Jordan Research and Training Reactor (JRTR) real-time simulator for operating staff training. The main purpose of this simulator is operator training, but we modified this simulator as a dynamic test-bed to test the reactor regulating system in HANARO or JRTR before installation. The simulator configuration is divided into hardware and software. The simulator hardware consists of a host computer, 6 operator stations, a network switch, and a large display panel. The simulator software is divided into three major parts: a mathematical modeling module, which executes the plant dynamic modeling program in real-time, an instructor station module that manages user instructions, and a human machine interface (HMI) module. The developed research reactors are installed in the Korea Atomic Energy Research Institute nuclear training center for reactor operator training. To use the simulator as a dynamic test-bed, the reactor regulating system modeling software of the simulator was replaced by a hardware controller and the simulator and target controller were interfaced with a hard-wired and network-based interface.

  16. Static and dynamic optimization of CAPE problems using a Model Testbed

    DEFF Research Database (Denmark)

    This paper presents a new computer aided tool for setting up and solving CAPE related static and dynamic optimisation problems. The Model Testbed (MOT) offers an integrated environment for setting up and solving a very large range of CAPE problems, including complex optimisation problems...... and dynamic optimisation, and how interfacing of solvers and seamless information flow can lead to more efficient solution of process design problems....

  17. Review of experiments and calculation procedures for ship collision and grounding damage

    DEFF Research Database (Denmark)

    Liu, Bin; Pedersen, Preben Terndrup; Zhu, Ling

    2018-01-01

    Abstract The paper presents a review of experiments and calculation procedures for the resistances of ship structural components subjected to impact loadings. The purpose of the paper is to highlight the importance of large-scale collision and grounding experiments and to discuss the technical...... and material characteristics. In recent literature, analytical and numerical calculations provide relatively accurate prediction of the purely plastic responses of ship structures under impact loads, but universal approaches have not been found for fracture predictions. The existing formulae for failure...

  18. Final Harvest of Above-Ground Biomass and Allometric Analysis of the Aspen FACE Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Mark E. Kubiske

    2013-04-15

    The Aspen FACE experiment, located at the US Forest Service Harshaw Research Facility in Oneida County, Wisconsin, exposes the intact canopies of model trembling aspen forests to increased concentrations of atmospheric CO2 and O3. The first full year of treatments was 1998 and final year of elevated CO2 and O3 treatments is scheduled for 2009. This proposal is to conduct an intensive, analytical harvest of the above-ground parts of 24 trees from each of the 12, 30 m diameter treatment plots (total of 288 trees) during June, July & August 2009. This above-ground harvest will be carefully coordinated with the below-ground harvest proposed by D.F. Karnosky et al. (2008 proposal to DOE). We propose to dissect harvested trees according to annual height growth increment and organ (main stem, branch orders, and leaves) for calculation of above-ground biomass production and allometric comparisons among aspen clones, species, and treatments. Additionally, we will collect fine root samples for DNA fingerprinting to quantify biomass production of individual aspen clones. This work will produce a thorough characterization of above-ground tree and stand growth and allocation above ground, and, in conjunction with the below ground harvest, total tree and stand biomass production, allocation, and allometry.

  19. Analysis, modeling, and simulation (AMS) testbed development and evaluation to support dynamic mobility applications (DMA) and active transportation and demand management (ATDM) programs — evaluation report for ATDM program. [supporting datasets - Pasadena Testbed

    Science.gov (United States)

    2017-07-26

    This zip file contains POSTDATA.ATT (.ATT); Print to File (.PRN); Portable Document Format (.PDF); and document (.DOCX) files of data to support FHWA-JPO-16-385, Analysis, modeling, and simulation (AMS) testbed development and evaluation to support d...

  20. SPoRT's Participation in the GOES-R Proving Ground Activity

    Science.gov (United States)

    Jedlovec, Gary; Fuell, Kevin; Smith, Matthew; Stano, Geoffrey; Molthan, Andrew

    2011-01-01

    data to operational decision support systems like NAWIPS, AWIPS, AWIPS2, and Google Earth. Recent SPoRT Proving Ground activities supporting the development and use of a pseudo GLM total lightning product and the transition of the AWG s Convective Initiation (CI) product, both of which were available in AWIPS and AWIPS II environments, by forecasters during the Hazardous Weather Testbed (HWT) Spring Experiment. SPoRT is also providing a suite of SEVIRI and MODIS RGB image products, and a high resolution composite SST product to several National Centers for use in there ongoing demonstration activities. Additionally, SPoRT has involved numerous WFOs in the evaluation of a GOES-MODIS hybrid product which brings ABI-like data sets in front of the forecaster for everyday use. An overview of this activity will be presented at the conference.

  1. Experiments and simulation of a net closing mechanism for tether-net capture of space debris

    Science.gov (United States)

    Sharf, Inna; Thomsen, Benjamin; Botta, Eleonora M.; Misra, Arun K.

    2017-10-01

    This research addresses the design and testing of a debris containment system for use in a tether-net approach to space debris removal. The tether-net active debris removal involves the ejection of a net from a spacecraft by applying impulses to masses on the net, subsequent expansion of the net, the envelopment and capture of the debris target, and the de-orbiting of the debris via a tether to the chaser spacecraft. To ensure a debris removal mission's success, it is important that the debris be successfully captured and then, secured within the net. To this end, we present a concept for a net closing mechanism, which we believe will permit consistently successful debris capture via a simple and unobtrusive design. This net closing system functions by extending the main tether connecting the chaser spacecraft and the net vertex to the perimeter and around the perimeter of the net, allowing the tether to actuate closure of the net in a manner similar to a cinch cord. A particular embodiment of the design in a laboratory test-bed is described: the test-bed itself is comprised of a scaled-down tether-net, a supporting frame and a mock-up debris. Experiments conducted with the facility demonstrate the practicality of the net closing system. A model of the net closure concept has been integrated into the previously developed dynamics simulator of the chaser/tether-net/debris system. Simulations under tether tensioning conditions demonstrate the effectiveness of the closure concept for debris containment, in the gravity-free environment of space, for a realistic debris target. The on-ground experimental test-bed is also used to showcase its utility for validating the dynamics simulation of the net deployment, and a full-scale automated setup would make possible a range of validation studies of other aspects of a tether-net debris capture mission.

  2. Electronic ground support equipment for the Cluster Electric Field and Wave Experiment

    International Nuclear Information System (INIS)

    Sten, T.A.

    1992-10-01

    In a collaboration between ESA and NASA, ionosphere plasma structures will be studied by four indentical space probes to be launched in 1995 from French Guiana. The Electric Field and Wave (EFW) experiment will be designed to measure electric field and density fluctations by means of four sensors, each deployed on a 50 meter wire boom. In order to perform comprehensive tests and calibrations of the EFW experiment, computer controlled electronic ground support equipment has been developed. This report describes the hardware of the equipment, produced and assembled at the University of Oslo. 15 figs

  3. Testbed diversity as a fundamental principle for effective ICS security research

    OpenAIRE

    Green, Benjamin; Frey, Sylvain Andre Francis; Rashid, Awais; Hutchison, David

    2016-01-01

    The implementation of diversity in testbeds is essential to understanding and improving the security and resilience of Industrial Control Systems (ICS). Employing a wide spec- trum of equipment, diverse networks, and business processes, as deployed in real-life infrastructures, is particularly diffi- cult in experimental conditions. However, this level of di- versity is key from a security perspective, as attackers can exploit system particularities and process intricacies to their advantage....

  4. Conceptual Design for a Dual-Bell Rocket Nozzle System Using a NASA F-15 Airplane as the Flight Testbed

    Science.gov (United States)

    Jones, Daniel S.; Ruf, Joseph H.; Bui, Trong T.; Martinez, Martel; St. John, Clinton W.

    2014-01-01

    The dual-bell rocket nozzle was first proposed in 1949, offering a potential improvement in rocket nozzle performance over the conventional-bell nozzle. Despite the performance advantages that have been predicted, both analytically and through static test data, the dual-bell nozzle has still not been adequately tested in a relevant flight environment. In 2013 a proposal was constructed that offered a National Aeronautics and Space Administration (NASA) F-15 airplane as the flight testbed, with the plan to operate a dual-bell rocket nozzle during captive-carried flight. If implemented, this capability will permit nozzle operation into an external flow field similar to that of a launch vehicle, and facilitate an improved understanding of dual-bell nozzle plume sensitivity to external flow-field effects. More importantly, this flight testbed can be utilized to help quantify the performance benefit with the dual-bell nozzle, as well as to advance its technology readiness level. Toward this ultimate goal, this report provides plans for future flights to quantify the external flow field of the airplane near the nozzle experiment, as well as details on the conceptual design for the dual-bell nozzle cold-flow propellant feed system integration within the NASA F-15 Propulsion Flight Test Fixture. The current study shows that this concept of flight research is feasible, and could result in valuable flight data for the dual-bell nozzle.

  5. The CMS integration grid testbed

    Energy Technology Data Exchange (ETDEWEB)

    Graham, Gregory E.

    2004-08-26

    The CMS Integration Grid Testbed (IGT) comprises USCMS Tier-1 and Tier-2 hardware at the following sites: the California Institute of Technology, Fermi National Accelerator Laboratory, the University of California at San Diego, and the University of Florida at Gainesville. The IGT runs jobs using the Globus Toolkit with a DAGMan and Condor-G front end. The virtual organization (VO) is managed using VO management scripts from the European Data Grid (EDG). Gridwide monitoring is accomplished using local tools such as Ganglia interfaced into the Globus Metadata Directory Service (MDS) and the agent based Mona Lisa. Domain specific software is packaged and installed using the Distribution After Release (DAR) tool of CMS, while middleware under the auspices of the Virtual Data Toolkit (VDT) is distributed using Pacman. During a continuous two month span in Fall of 2002, over 1 million official CMS GEANT based Monte Carlo events were generated and returned to CERN for analysis while being demonstrated at SC2002. In this paper, we describe the process that led to one of the world's first continuously available, functioning grids.

  6. Patients' experiences with home parenteral nutrition: A grounded theory study.

    Science.gov (United States)

    Wong, Christina; Lucas, Beverley; Wood, Diana

    2018-04-01

    Parenteral nutrition (PN) provides nourishment and hydration as an intravenous infusion to patients with intestinal failure (IF). The aim of the study is to generate theory that explains the experiences of adult patients living with home parenteral nutrition (HPN) and complex medication regimens. A grounded theory methodology was used to explore the experiences of twelve patients receiving HPN. A semi-structured interview was conducted and recorded in each participant's home setting. Each interview was transcribed verbatim. The simultaneous process of data collection and analysis was followed reflecting the principles of the constant comparative approach. A total of 15 patients gave written consent, with 12 of them agreeing to be interviewed. All the participants had previously undergone surgery as a result of chronic ill health or sudden illness. Analysis revealed two core categories: stoma and HPN, and these were supported by the subcategories: maintaining stoma output, access to toilets, managing dietary changes, maintaining the HPN infusion routine, access to technical help to set up an HPN infusion, mobility with HPN equipment and general health changes. The strategy of living with loss was demonstrated by all the participants, and this was supported by the action strategies of maintaining daily activities and social interactions. This study generates new understanding and insight into the views and experiences of patients receiving HPN in the UK. The findings from these participants have been shown to resonate with the Kubler-Ross Model [1] of the five stages of grief. The theory of living with loss was generated by the use of a grounded theory methodology. This small scale exploratory study reveals opportunities for improvements in practice to be considered by the nutrition support team (NST) and other healthcare professionals involved in the patient's hospital stay prior to discharge on HPN. Copyright © 2018 European Society for Clinical Nutrition and

  7. Experiments Using a Ground-Based Electrostatic Levitator and Numerical Modeling of Melt Convection for the Iron-Cobalt System in Support of Space Experiments

    Science.gov (United States)

    Lee, Jonghyun; SanSoucie, Michael P.

    2017-08-01

    Materials research is being conducted using an electromagnetic levitator installed in the International Space Station. Various metallic alloys were tested to elucidate unknown links among the structures, processes, and properties. To accomplish the mission of these space experiments, several ground-based activities have been carried out. This article presents some of our ground-based supporting experiments and numerical modeling efforts. Mass evaporation of Fe50Co50, one of flight compositions, was predicted numerically and validated by the tests using an electrostatic levitator (ESL). The density of various compositions within the Fe-Co system was measured with ESL. These results are being served as reference data for the space experiments. The convection inside a electromagnetically-levitated droplet was also modeled to predict the flow status, shear rate, and convection velocity under various process parameters, which is essential information for designing and analyzing the space experiments of some flight compositions influenced by convection.

  8. A grounded theory of bisexual individuals' experiences of help seeking.

    Science.gov (United States)

    MacKay, Jenna; Robinson, Margaret; Pinder, Sarah; Ross, Lori E

    2017-01-01

    Bisexual people constitute the largest sexual minority group in North America and experience significant mental health disparities in relation to heterosexuals, gays, and lesbians. In this article, we will examine the process and experience of help seeking among bisexuals. This was a community-based study that collected qualitative interview data from 41 diverse bisexual people from across Ontario, Canada. We analyzed the interview data using grounded theory and constructed an understanding of bisexuals' experiences of help seeking. We have conceptualized an overarching model that illustrates 4 interrelated stages: (a) the consideration of services, (b) the process of finding services, (c) barriers and facilitators to accessing services, and (d) experience of service utilization. This model is nonlinear, in that participants do not necessarily move through stages in sequence. Although many stages are experienced at the individual level, they are simultaneously informed by multiple factors at interpersonal and system levels. Our findings suggest a need for interventions at the policy, service and provider levels to improve accessibility of culturally competent services for this population. Understanding the mental health experiences of bisexual people will allow mental health professionals to build competencies working with this population and thereby contribute to a reduction in mental health disparities. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  9. Creative thinking of design and redesign on SEAT aircraft cabin testbed: a case study

    NARCIS (Netherlands)

    Tan, C.F.; Chen, W.; Rauterberg, G.W.M.

    2009-01-01

    this paper, the intuition approach in the design and redesign of the environmental friendly innovative aircraft cabin simulator is presented.. The aircraft cabin simulator is a testbed that used for European Project SEAT (Smart tEchnologies for Stress free Air Travel). The SEAT project aims to

  10. EMERGE - ESnet/MREN Regional Science Grid Experimental NGI Testbed

    Energy Technology Data Exchange (ETDEWEB)

    Mambretti, Joe; DeFanti, Tom; Brown, Maxine

    2001-07-31

    This document is the final report on the EMERGE Science Grid testbed research project from the perspective of the International Center for Advanced Internet Research (iCAIR) at Northwestern University, which was a subcontractor to this UIC project. This report is a compilation of information gathered from a variety of materials related to this project produced by multiple EMERGE participants, especially those at Electronic Visualization Lab (EVL) at the University of Illinois at Chicago (UIC), Argonne National Lab and iCAIR. The EMERGE Science Grid project was managed by Tom DeFanti, PI from EVL at UIC.

  11. Real-Time Emulation of Heterogeneous Wireless Networks with End-to-Edge Quality of Service Guarantees: The AROMA Testbed

    Directory of Open Access Journals (Sweden)

    Anna Umbert

    2010-01-01

    Full Text Available This work presents and describes the real-time testbed for all-IP Beyond 3G (B3G heterogeneous wireless networks that has been developed in the framework of the European IST AROMA project. The main objective of the AROMA testbed is to provide a highly accurate and realistic framework where the performance of algorithms, policies, protocols, services, and applications for a complete heterogeneous wireless network can be fully assessed and evaluated before bringing them to a real system. The complexity of the interaction between all-IP B3G systems and user applications, while dealing with the Quality of Service (QoS concept, motivates the development of this kind of emulation platform where different solutions can be tested in realistic conditions that could not be achieved by means of simple offline simulations. This work provides an in-depth description of the AROMA testbed, emphasizing many interesting implementation details and lessons learned during the development of the tool that may result helpful to other researchers and system engineers in the development of similar emulation platforms. Several case studies are also presented in order to illustrate the full potential and capabilities of the presented emulation platform.

  12. Development of an autonomous power system testbed

    International Nuclear Information System (INIS)

    Barton, J.R.; Adams, T.; Liffring, M.E.

    1985-01-01

    A power system testbed has been assembled to advance the development of large autonomous electrical power systems required for the space station, spacecraft, and aircraft. The power system for this effort was designed to simulate single- or dual-bus autonomous power systems, or autonomous systems that reconfigure from a single bus to a dual bus following a severe fault. The approach taken was to provide a flexible power system design with two computer systems for control and management. One computer operates as the control system and performs basic control functions, data and command processing, charge control, and provides status to the second computer. The second computer contains expert system software for mission planning, load management, fault identification and recovery, and sends load and configuration commands to the control system

  13. The First-Year University Experience for Sexual Minority Students: A Grounded Theory Exploration

    Science.gov (United States)

    Alessi, Edward J.; Sapiro, Beth; Kahn, Sarilee; Craig, Shelley L.

    2017-01-01

    This exploratory study used grounded theory to understand the role of minority stress on the first-year experience of lesbian, gay, bisexual, queer, and questioning emerging adults attending a university in the Northeastern part of the United States. Twenty-one lesbian, gay, bisexual, queer, and questioning sophomores participated in focus groups…

  14. Test-bed for the remote health monitoring system for bridge structures using FBG sensors

    Science.gov (United States)

    Lee, Chin-Hyung; Park, Ki-Tae; Joo, Bong-Chul; Hwang, Yoon-Koog

    2009-05-01

    This paper reports on test-bed for the long-term health monitoring system for bridge structures employing fiber Bragg grating (FBG) sensors, which is remotely accessible via the web, to provide real-time quantitative information on a bridge's response to live loading and environmental changes, and fast prediction of the structure's integrity. The sensors are attached on several locations of the structure and connected to a data acquisition system permanently installed onsite. The system can be accessed through remote communication using an optical cable network, through which the evaluation of the bridge behavior under live loading can be allowed at place far away from the field. Live structural data are transmitted continuously to the server computer at the central office. The server computer is connected securely to the internet, where data can be retrieved, processed and stored for the remote web-based health monitoring. Test-bed revealed that the remote health monitoring technology will enable practical, cost-effective, and reliable condition assessment and maintenance of bridge structures.

  15. Tests of the gravitational redshift effect in space-born and ground-based experiments

    Science.gov (United States)

    Vavilova, I. B.

    2018-02-01

    This paper provides a brief overview of experiments as concerns with the tests of the gravitational redshift (GRS) effect in ground-based and space-born experiments. In particular, we consider the GRS effects in the gravitational field of the Earth, the major planets of the Solar system, compact stars (white dwarfs and neutron stars) where this effect is confirmed with a higher accuracy. We discuss availabilities to confirm the GRS effect for galaxies and galaxy clusters in visible and X-ray ranges of the electromagnetic spectrum.

  16. A low-cost test-bed for real-time landmark tracking

    Science.gov (United States)

    Csaszar, Ambrus; Hanan, Jay C.; Moreels, Pierre; Assad, Christopher

    2007-04-01

    A low-cost vehicle test-bed system was developed to iteratively test, refine and demonstrate navigation algorithms before attempting to transfer the algorithms to more advanced rover prototypes. The platform used here was a modified radio controlled (RC) car. A microcontroller board and onboard laptop computer allow for either autonomous or remote operation via a computer workstation. The sensors onboard the vehicle represent the types currently used on NASA-JPL rover prototypes. For dead-reckoning navigation, optical wheel encoders, a single axis gyroscope, and 2-axis accelerometer were used. An ultrasound ranger is available to calculate distance as a substitute for the stereo vision systems presently used on rovers. The prototype also carries a small laptop computer with a USB camera and wireless transmitter to send real time video to an off-board computer. A real-time user interface was implemented that combines an automatic image feature selector, tracking parameter controls, streaming video viewer, and user generated or autonomous driving commands. Using the test-bed, real-time landmark tracking was demonstrated by autonomously driving the vehicle through the JPL Mars yard. The algorithms tracked rocks as waypoints. This generated coordinates calculating relative motion and visually servoing to science targets. A limitation for the current system is serial computing-each additional landmark is tracked in order-but since each landmark is tracked independently, if transferred to appropriate parallel hardware, adding targets would not significantly diminish system speed.

  17. An overview of the U.S. Army Research Laboratory's Sensor Information Testbed for Collaborative Research Environment (SITCORE) and Automated Online Data Repository (AODR) capabilities

    Science.gov (United States)

    Ward, Dennis W.; Bennett, Kelly W.

    2017-05-01

    The Sensor Information Testbed COllaberative Research Environment (SITCORE) and the Automated Online Data Repository (AODR) are significant enablers of the U.S. Army Research Laboratory (ARL)'s Open Campus Initiative and together create a highly-collaborative research laboratory and testbed environment focused on sensor data and information fusion. SITCORE creates a virtual research development environment allowing collaboration from other locations, including DoD, industry, academia, and collation facilities. SITCORE combined with AODR provides end-toend algorithm development, experimentation, demonstration, and validation. The AODR enterprise allows the U.S. Army Research Laboratory (ARL), as well as other government organizations, industry, and academia to store and disseminate multiple intelligence (Multi-INT) datasets collected at field exercises and demonstrations, and to facilitate research and development (R and D), and advancement of analytical tools and algorithms supporting the Intelligence, Surveillance, and Reconnaissance (ISR) community. The AODR provides a potential central repository for standards compliant datasets to serve as the "go-to" location for lessons-learned and reference products. Many of the AODR datasets have associated ground truth and other metadata which provides a rich and robust data suite for researchers to develop, test, and refine their algorithms. Researchers download the test data to their own environments using a sophisticated web interface. The AODR allows researchers to request copies of stored datasets and for the government to process the requests and approvals in an automated fashion. Access to the AODR requires two-factor authentication in the form of a Common Access Card (CAC) or External Certificate Authority (ECA)

  18. Evaluasi Kinerja Layanan IPTV pada Jaringan Testbed WiMAX Berbasis Standar IEEE 802.16-2004

    Directory of Open Access Journals (Sweden)

    Prasetiyono Hari Mukti

    2015-09-01

    Full Text Available In this paper, a performance evaluation for IPTV Services over WiMAX testbed based on IEEE Standard 802.16-2004 will be described. The performance of the proposed system is evaluated in terms of delay, jitter, throughput and packet loss. Service performance evaluations are conducted on network topology of point-to-point in the variation of background traffic with different scheduling types. Background traffic is injected into the system to give the sense that the proposed system has variation traffic load. Scheduling type which are used in this paper are Best Effort (BE, Non-Real-Time Polling Service (nrtPS, Real-Time Polling Service (rtPS and Unsolicited Grant Service (UGS. The expemerintal results of IPTV service performance over the testbed network show that the maximum average of delay, jitter, packet loss and jitter are 16.581 ms, 58.515 ms, 0.67 Mbps dan 10.96%, respectively.

  19. High Energy Nuclear Database: A Testbed for Nuclear Data Information Technology

    International Nuclear Information System (INIS)

    Brown, D A; Vogt, R; Beck, B; Pruet, J

    2007-01-01

    We describe the development of an on-line high-energy heavy-ion experimental database. When completed, the database will be searchable and cross-indexed with relevant publications, including published detector descriptions. While this effort is relatively new, it will eventually contain all published data from older heavy-ion programs as well as published data from current and future facilities. These data include all measured observables in proton-proton, proton-nucleus and nucleus-nucleus collisions. Once in general use, this database will have tremendous scientific payoff as it makes systematic studies easier and allows simpler benchmarking of theoretical models for a broad range of experiments. Furthermore, there is a growing need for compilations of high-energy nuclear data for applications including stockpile stewardship, technology development for inertial confinement fusion, target and source development for upcoming facilities such as the International Linear Collider and homeland security. This database is part of a larger proposal that includes the production of periodic data evaluations and topical reviews. These reviews would provide an alternative and impartial mechanism to resolve discrepancies between published data from rival experiments and between theory and experiment. Since this database will be a community resource, it requires the high-energy nuclear physics community's financial and manpower support. This project serves as a testbed for the further development of an object-oriented nuclear data format and database system. By using ''off-the-shelf'' software tools and techniques, the system is simple, robust, and extensible. Eventually we envision a ''Grand Unified Nuclear Format'' encapsulating data types used in the ENSDF, ENDF/B, EXFOR, NSR and other formats, including processed data formats

  20. Using Grounded Theory Method to Capture and Analyze Health Care Experiences

    Science.gov (United States)

    Foley, Geraldine; Timonen, Virpi

    2015-01-01

    Objective Grounded theory (GT) is an established qualitative research method, but few papers have encapsulated the benefits, limits, and basic tenets of doing GT research on user and provider experiences of health care services. GT can be used to guide the entire study method, or it can be applied at the data analysis stage only. Methods We summarize key components of GT and common GT procedures used by qualitative researchers in health care research. We draw on our experience of conducting a GT study on amyotrophic lateral sclerosis patients’ experiences of health care services. Findings We discuss why some approaches in GT research may work better than others, particularly when the focus of study is hard-to-reach population groups. We highlight the flexibility of procedures in GT to build theory about how people engage with health care services. Conclusion GT enables researchers to capture and understand health care experiences. GT methods are particularly valuable when the topic of interest has not previously been studied. GT can be applied to bring structure and rigor to the analysis of qualitative data. PMID:25523315

  1. Living with a Star (LWS) Space Environment Testbeds (SET), Mission Carrier Overview and Capabilities

    Science.gov (United States)

    Patschke, Robert; Barth, Janet; Label, Ken; Mariano, Carolyn; Pham, Karen; Brewer, Dana; Cuviello, Michael; Kobe, David; Wu, Carl; Jarosz, Donald

    2004-01-01

    NASA has initiated the Living With a Star (LWS) Program to develop the scientific understanding to address the aspects of the Connected Sun-Earth system that affect life and society. A goal of the program is to bridge the gap between science, engineering, and user application communities. This will enable future science, operational, and commercial objectives in space and atmospheric environments by improving engineering approaches to the accommodation and/or mitigation of the effects of solar variability on technological systems. The three program elements of the LWS Program are Science Missions; Targeted Research and Technology; and Space Environment Testbeds (SETS). SET is an ideal platform for small experiments performing research on space environment effects on technologies and on the mitigation of space weather effects. A short description of the LWS Program will be given, and the SET will be described in detail, giving the mission objectives, available carrier services, and upcoming flight opportunities.

  2. Implementation of Real-Time Feedback Flow Control Algorithms on a Canonical Testbed

    Science.gov (United States)

    Tian, Ye; Song, Qi; Cattafesta, Louis

    2005-01-01

    This report summarizes the activities on "Implementation of Real-Time Feedback Flow Control Algorithms on a Canonical Testbed." The work summarized consists primarily of two parts. The first part summarizes our previous work and the extensions to adaptive ID and control algorithms. The second part concentrates on the validation of adaptive algorithms by applying them to a vibration beam test bed. Extensions to flow control problems are discussed.

  3. Exogenous spatial attention influences figure-ground assignment.

    Science.gov (United States)

    Vecera, Shaun P; Flevaris, Anastasia V; Filapek, Joseph C

    2004-01-01

    In a hierarchical stage account of vision, figure-ground assignment is thought to be completed before the operation of focal spatial attention. Results of previous studies have supported this account by showing that unpredictive, exogenous spatial precues do not influence figure-ground assignment, although voluntary attention can influence figure-ground assignment. However, in these studies, attention was not summoned directly to a region in a figure-ground display. In three experiments, we addressed the relationship between figure-ground assignment and visuospatial attention. In Experiment 1, we replicated the finding that exogenous precues do not influence figure-ground assignment when they direct attention outside of a figure-ground stimulus. In Experiment 2, we demonstrated that exogenous attention can influence figure-ground assignment if it is directed to one of the regions in a figure-ground stimulus. In Experiment 3, we demonstrated that exogenous attention can influence figure-ground assignment in displays that contain a Gestalt figure-ground cue; this result suggests that figure-ground processes are not entirely completed prior to the operation of focal spatial attention. Exogenous spatial attention acts as a cue for figure-ground assignment and can affect the outcome of figure-ground processes.

  4. Coral-based Proxy Records of Ocean Acidification: A Pilot Study at the Puerto Rico Test-bed Site

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Coral cores collected nearby the Atlantic Ocean Acidification Test-bed (AOAT) at La Parguera, Puerto Rico were used to characterize the relationship between...

  5. Smart Grid: Network simulator for smart grid test-bed

    International Nuclear Information System (INIS)

    Lai, L C; Ong, H S; Che, Y X; Do, N Q; Ong, X J

    2013-01-01

    Smart Grid become more popular, a smaller scale of smart grid test-bed is set up at UNITEN to investigate the performance and to find out future enhancement of smart grid in Malaysia. The fundamental requirement in this project is design a network with low delay, no packet drop and with high data rate. Different type of traffic has its own characteristic and is suitable for different type of network and requirement. However no one understands the natural of traffic in smart grid. This paper presents the comparison between different types of traffic to find out the most suitable traffic for the optimal network performance.

  6. Optimizing Electric Vehicle Coordination Over a Heterogeneous Mesh Network in a Scaled-Down Smart Grid Testbed

    DEFF Research Database (Denmark)

    Bhattarai, Bishnu Prasad; Lévesque, Martin; Maier, Martin

    2015-01-01

    High penetration of renewable energy sources and electric vehicles (EVs) create power imbalance and congestion in the existing power network, and hence causes significant problems in the control and operation. Despite investing huge efforts from the electric utilities, governments, and researchers......, smart grid (SG) is still at the developmental stage to address those issues. In this regard, a smart grid testbed (SGT) is desirable to develop, analyze, and demonstrate various novel SG solutions, namely demand response, real-time pricing, and congestion management. In this paper, a novel SGT...... is developed in a laboratory by scaling a 250 kVA, 0.4 kV real low-voltage distribution feeder down to 1 kVA, 0.22 kV. Information and communication technology is integrated in the scaled-down network to establish real-time monitoring and control. The novelty of the developed testbed is demonstrated...

  7. A Real-Time GPP Software-Defined Radio Testbed for the Physical Layer of Wireless Standards

    NARCIS (Netherlands)

    Schiphorst, Roelof; Hoeksema, F.W.; Slump, Cornelis H.

    2005-01-01

    We present our contribution to the general-purpose-processor-(GPP)-based radio. We describe a baseband software-defined radio testbed for the physical layer of wireless LAN standards. All physical layer functions have been successfully mapped on a Pentium 4 processor that performs these functions in

  8. A Method to Derive Monitoring Variables for a Cyber Security Test-bed of I and C System

    Energy Technology Data Exchange (ETDEWEB)

    Han, Kyung Soo; Song, Jae Gu; Lee, Joung Woon; Lee, Cheol Kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    In the IT field, monitoring techniques have been developed to protect the systems connected by networks from cyber attacks and incidents. For the development of monitoring systems for I and C cyber security, it is necessary to review the monitoring systems in the IT field and derive cyber security-related monitoring variables among the proprietary operating information about the I and C systems. Tests for the development and application of these monitoring systems may cause adverse effects on the I and C systems. To analyze influences on the system and safely intended variables, the construction of an I and C system Test-bed should be preceded. This article proposes a method of deriving variables that should be monitored through a monitoring system for cyber security as a part of I and C Test-bed. The surveillance features and the monitored variables of NMS(Network Management System), a monitoring technique in the IT field, were reviewed in section 2. In Section 3, the monitoring variables for an I and C cyber security were derived by the of NMS and the investigation for information used for hacking techniques that can be practiced against I and C systems. The monitoring variables of NMS in the IT field and the information about the malicious behaviors used for hacking were derived as expected variables to be monitored for an I and C cyber security research. The derived monitoring variables were classified into the five functions of NMS for efficient management. For the cyber security of I and C systems, the vulnerabilities should be understood through a penetration test etc. and an assessment of influences on the actual system should be carried out. Thus, constructing a test-bed of I and C systems is necessary for the safety system in operation. In the future, it will be necessary to develop a logging and monitoring system for studies on the vulnerabilities of I and C systems with test-beds.

  9. A Method to Derive Monitoring Variables for a Cyber Security Test-bed of I and C System

    International Nuclear Information System (INIS)

    Han, Kyung Soo; Song, Jae Gu; Lee, Joung Woon; Lee, Cheol Kwon

    2013-01-01

    In the IT field, monitoring techniques have been developed to protect the systems connected by networks from cyber attacks and incidents. For the development of monitoring systems for I and C cyber security, it is necessary to review the monitoring systems in the IT field and derive cyber security-related monitoring variables among the proprietary operating information about the I and C systems. Tests for the development and application of these monitoring systems may cause adverse effects on the I and C systems. To analyze influences on the system and safely intended variables, the construction of an I and C system Test-bed should be preceded. This article proposes a method of deriving variables that should be monitored through a monitoring system for cyber security as a part of I and C Test-bed. The surveillance features and the monitored variables of NMS(Network Management System), a monitoring technique in the IT field, were reviewed in section 2. In Section 3, the monitoring variables for an I and C cyber security were derived by the of NMS and the investigation for information used for hacking techniques that can be practiced against I and C systems. The monitoring variables of NMS in the IT field and the information about the malicious behaviors used for hacking were derived as expected variables to be monitored for an I and C cyber security research. The derived monitoring variables were classified into the five functions of NMS for efficient management. For the cyber security of I and C systems, the vulnerabilities should be understood through a penetration test etc. and an assessment of influences on the actual system should be carried out. Thus, constructing a test-bed of I and C systems is necessary for the safety system in operation. In the future, it will be necessary to develop a logging and monitoring system for studies on the vulnerabilities of I and C systems with test-beds

  10. Onboard Autonomy and Ground Operations Automation for the Intelligent Payload Experiment (IPEX) CubeSat Mission

    Science.gov (United States)

    Chien, Steve; Doubleday, Joshua; Ortega, Kevin; Tran, Daniel; Bellardo, John; Williams, Austin; Piug-Suari, Jordi; Crum, Gary; Flatley, Thomas

    2012-01-01

    The Intelligent Payload Experiment (IPEX) is a cubesat manifested for launch in October 2013 that will flight validate autonomous operations for onboard instrument processing and product generation for the Intelligent Payload Module (IPM) of the Hyperspectral Infra-red Imager (HyspIRI) mission concept. We first describe the ground and flight operations concept for HyspIRI IPM operations. We then describe the ground and flight operations concept for the IPEX mission and how that will validate HyspIRI IPM operations. We then detail the current status of the mission and outline the schedule for future development.

  11. Using the EXECO toolbox to perform automatic and reproducible cloud experiments

    OpenAIRE

    Imbert , Matthieu; Pouilloux , Laurent; Rouzaud-Cornabas , Jonathan; Lèbre , Adrien; Hirofuchi , Takahiro

    2013-01-01

    International audience; his paper describes EXECO, a library that provides easy and efficient control of local or remote, standalone or parallel, processes execution, as well as tools designed for scripting distributed computing experiments on any computing platform. After discussing the EXECO internals, we illustrate its interest by presenting two experiments dealing with virtualization technologies on the Grid’5000 testbed.

  12. THAI-SPICE: Testbed for High-Acuity Imaging – Stable Photometry and ImageMotion Compensation Experiment

    Science.gov (United States)

    Young, Eliot

    THAI-SPICE is the Testbed for High-Acuity Imaging - Stable Photometry and ImageMotion Compensation Experiment - It is a lead proposal, accompanied by a coInstitutional proposal from MIT LL. The overarching goal of THAI-SPICE is to advance balloonborne telescopes to the point where they can surpass HST in terms of spatial resolution in visible wavelengths and surpass the Kepler mission in terms of observing exoplanet transits. Balloon-borne telescopes are becoming an important part of NASA's observing programs - each 100-day super-pressure balloon flight will provide 1000 hours of dark time observing, equivalent to about 1/3 of the total on-target time allocated in an HST cycle across its entire portfolio of science programs. However, balloon-borne telescopes face unique challenges from the stratospheric thermal environment and the pointing stability of a suspended platform. This proposal will study and test three areas of development that will enable high-acuity image quality and stable photometry from balloon-borne telescopes. - Passive thermal control and stabilization of balloon-borne OTAs (Optical Tube Assemblies). Recent modeling suggests that an appropriate arrangement of sunshields, earth-shields and telescope insulation can reduce diurnal temperature excursions from more than 40°C to less than 2°C. Furthermore, modeling also suggests that the steadystate temperature of an OTA can be reduced to temperatures near 180 K, an advantage for infrared observing programs. However, most modeling packages (e.g., Thermal Desktop) do not accurately account for convection in the 3 torr or 8 torr environment of zeropressure or super-pressure balloons. In fact, it is hard to tell whether radiation or convection is a more significant cooling mechanism at super-pressure balloon altitudes. We propose to verify or update Thermal Desktop results with a series of experiments using an instrumented OTA and sun- and earth-shields. The payoff from this experiment will be balloon

  13. Test-bed Assessment of Communication Technologies for a Power-Balancing Controller

    DEFF Research Database (Denmark)

    Findrik, Mislav; Pedersen, Rasmus; Hasenleithner, Eduard

    2016-01-01

    and control. In this paper, we present a Smart Grid test-bed that integrates various communication technologies and deploys a power balancing controller for LV grids. Control performance of the introduced power balancing controller is subsequently investigated and its robustness to communication network cross......Due to growing need for sustainable energy, increasing number of different renewable energy resources are being connected into distribution grids. In order to efficiently manage a decentralized power generation units, the smart grid will rely on communication networks for information exchange...

  14. Nitrate Accumulation and Leaching in Surface and Ground Water Based on Simulated Rainfall Experiments

    Science.gov (United States)

    Wang, Hong; Gao, Jian-en; Li, Xing-hua; Zhang, Shao-long; Wang, Hong-jie

    2015-01-01

    To evaluate the process of nitrate accumulation and leaching in surface and ground water, we conducted simulated rainfall experiments. The experiments were performed in areas of 5.3 m2 with bare slopes of 3° that were treated with two nitrogen fertilizer inputs, high (22.5 g/m2 NH4NO3) and control (no fertilizer), and subjected to 2 hours of rainfall, with. From the 1st to the 7th experiments, the same content of fertilizer mixed with soil was uniformly applied to the soil surface at 10 minutes before rainfall, and no fertilizer was applied for the 8th through 12th experiments. Initially, the time-series nitrate concentration in the surface flow quickly increased, and then it rapidly decreased and gradually stabilized at a low level during the fertilizer experiments. The nitrogen loss in the surface flow primarily occurred during the first 18.6 minutes of rainfall. For the continuous fertilizer experiments, the mean nitrate concentrations in the groundwater flow remained at less than 10 mg/L before the 5th experiment, and after the 7th experiment, these nitrate concentrations were greater than 10 mg/L throughout the process. The time-series process of the changing concentration in the groundwater flow exhibited the same parabolic trend for each fertilizer experiment. However, the time at which the nitrate concentration began to change lagged behind the start time of groundwater flow by approximately 0.94 hours on average. The experiments were also performed with no fertilizer. In these experiments, the mean nitrate concentration of groundwater initially increased continuously, and then, the process exhibited the same parabolic trend as the results of the fertilization experiments. The nitrate concentration decreased in the subsequent experiments. Eight days after the 12 rainfall experiments, 50.53% of the total nitrate applied remained in the experimental soil. Nitrate residues mainly existed at the surface and in the bottom soil layers, which represents a

  15. SABA: A Testbed for a Real-Time MIMO System

    Directory of Open Access Journals (Sweden)

    Brühl Lars

    2006-01-01

    Full Text Available The growing demand for high data rates for wireless communication systems leads to the development of new technologies to increase the channel capacity thus increasing the data rate. MIMO (multiple-input multiple-output systems are best qualified for these applications. In this paper, we present a MIMO test environment for high data rate transmissions in frequency-selective environments. An overview of the testbed is given, including the analyzed algorithms, the digital signal processing with a new highly parallel processor to perform the algorithms in real time, as well as the analog front-ends. A brief overview of the influence of polarization on the channel capacity is given as well.

  16. X-ray Pulsar Navigation Algorithms and Testbed for SEXTANT

    Science.gov (United States)

    Winternitz, Luke M. B.; Hasouneh, Monther A.; Mitchell, Jason W.; Valdez, Jennifer E.; Price, Samuel R.; Semper, Sean R.; Yu, Wayne H.; Ray, Paul S.; Wood, Kent S.; Arzoumanian, Zaven; hide

    2015-01-01

    The Station Explorer for X-ray Timing and Navigation Technology (SEXTANT) is a NASA funded technologydemonstration. SEXTANT will, for the first time, demonstrate real-time, on-board X-ray Pulsar-based Navigation (XNAV), a significant milestone in the quest to establish a GPS-like navigation capability available throughout our Solar System and beyond. This paper describes the basic design of the SEXTANT system with a focus on core models and algorithms, and the design and continued development of the GSFC X-ray Navigation Laboratory Testbed (GXLT) with its dynamic pulsar emulation capability. We also present early results from GXLT modeling of the combined NICER X-ray timing instrument hardware and SEXTANT flight software algorithms.

  17. Development and application of an actively controlled hybrid proton exchange membrane fuel cell - Lithium-ion battery laboratory test-bed based on off-the-shelf components

    Energy Technology Data Exchange (ETDEWEB)

    Yufit, V.; Brandon, N.P. [Dept. Earth Science and Engineering, Imperial College, London SW7 2AZ (United Kingdom)

    2011-01-15

    The use of commercially available components enables rapid prototyping and assembling of laboratory scale hybrid test-bed systems, which can be used to evaluate new hybrid configurations. The development of such a test-bed using an off-the-shelf PEM fuel cell, lithium-ion battery and DC/DC converter is presented here, and its application to a hybrid configuration appropriate for an unmanned underwater vehicle is explored. A control algorithm was implemented to regulate the power share between the fuel cell and the battery with a graphical interface to control, record and analyze the electrochemical and thermal parameters of the system. The results demonstrate the applicability of the test-bed and control algorithm for this application, and provide data on the dynamic electrical and thermal behaviour of the hybrid system. (author)

  18. The GOES-R Proving Ground: 2012 Update

    Science.gov (United States)

    Gurka, J.; Goodman, S. J.; Schmit, T.; Demaria, M.; Mostek, A.; Siewert, C.; Reed, B.

    2011-12-01

    close collaboration with NWS Training Division and its partners at COMET, CIMSS, CIRA and other offices. The training is used to prepare the participants of PG activities, such as the Hazardous Weather Testbed's Spring Experiment and other locations listed above. A key component of the proving ground is two-way interaction, where researchers introduce new products and techniques to forecasters and other scientists. The forecasters and other users then provide feedback and ideas for improved or new products and how to best incorporate these into NOAA's integrated observing and analysis operations. This presentation will provide examples of GOES-R proxy products and forecaster evaluations from experiments at the Storm Prediction Center (SPC), the National Hurricane Center (NHC), the Aviation Weather Center (AWC), and the Alaska Region.

  19. A testbed to explore the optimal electrical stimulation parameters for suppressing inter-ictal spikes in human hippocampal slices.

    Science.gov (United States)

    Min-Chi Hsiao; Pen-Ning Yu; Dong Song; Liu, Charles Y; Heck, Christi N; Millett, David; Berger, Theodore W

    2014-01-01

    New interventions using neuromodulatory devices such as vagus nerve stimulation, deep brain stimulation and responsive neurostimulation are available or under study for the treatment of refractory epilepsy. Since the actual mechanisms of the onset and termination of the seizure are still unclear, most researchers or clinicians determine the optimal stimulation parameters through trial-and-error procedures. It is necessary to further explore what types of electrical stimulation parameters (these may include stimulation frequency, amplitude, duration, interval pattern, and location) constitute a set of optimal stimulation paradigms to suppress seizures. In a previous study, we developed an in vitro epilepsy model using hippocampal slices from patients suffering from mesial temporal lobe epilepsy. Using a planar multi-electrode array system, inter-ictal activity from human hippocampal slices was consistently recorded. In this study, we have further transferred this in vitro seizure model to a testbed for exploring the possible neurostimulation paradigms to inhibit inter-ictal spikes. The methodology used to collect the electrophysiological data, the approach to apply different electrical stimulation parameters to the slices are provided in this paper. The results show that this experimental testbed will provide a platform for testing the optimal stimulation parameters of seizure cessation. We expect this testbed will expedite the process for identifying the most effective parameters, and may ultimately be used to guide programming of new stimulating paradigms for neuromodulatory devices.

  20. High energy nuclear database: a test-bed for nuclear data information technology

    International Nuclear Information System (INIS)

    Brown, D.A.; Vogt, R.; Beck, B.; Pruet, J.; Vogt, R.

    2008-01-01

    We describe the development of an on-line high-energy heavy-ion experimental database. When completed, the database will be searchable and cross-indexed with relevant publications, including published detector descriptions. While this effort is relatively new, it will eventually contain all published data from older heavy-ion programs as well as published data from current and future facilities. These data include all measured observables in proton-proton, proton-nucleus and nucleus-nucleus collisions. Once in general use, this database will have tremendous scientific payoff as it makes systematic studies easier and allows simpler benchmarking of theoretical models for a broad range of experiments. Furthermore, there is a growing need for compilations of high-energy nuclear data for applications including stockpile stewardship, technology development for inertial confinement fusion, target and source development for upcoming facilities such as the International Linear Collider and homeland security. This database is part of a larger proposal that includes the production of periodic data evaluations and topical reviews. These reviews would provide an alternative and impartial mechanism to resolve discrepancies between published data from rival experiments and between theory and experiment. Since this database will be a community resource, it requires the high-energy nuclear physics community's financial and manpower support. This project serves as a test-bed for the further development of an object-oriented nuclear data format and database system. By using 'off-the-shelf' software tools and techniques, the system is simple, robust, and extensible. Eventually we envision a 'Grand Unified Nuclear Format' encapsulating data types used in the ENSDF, Endf/B, EXFOR, NSR and other formats, including processed data formats. (authors)

  1. Midwifery students learning experiences in labor wards: a grounded theory.

    Science.gov (United States)

    Brunstad, Anne; Hjälmhult, Esther

    2014-12-01

    The labor ward is an important and challenging learning area for midwifery students. It is there the students learn in authentic complex situations, in intimate situations, with potential risk for the life and health of mothers and their babies. The aim of this study was to explore the main concern expressed by midwifery students in labor wards and how they handled this concern. A longitudinal study based on grounded theory methodology was used. The participants were 10 postgraduate midwifery students, from a University College in Norway. Data were gathered and analyzed throughout the 2-year postgraduate program, in the students first, third and fourth semesters. Every student was interviewed three times in a total of 15 single and three focus-group sessions. The grounded theory of "building relationships" explains how students dealt with their main concern: "how to gain access to learning experiences". This theory consisted of three strategies; a) controlling vulnerability, b) cultivating trust and c) obtaining acceptance. Clarifying discussions involving midwives and students may facilitate the process of building relationships and contribute to confident learning. Students appreciate it when the midwives initiate discussions about acute situations and state that a novice may perceive labor and childbirth as more frightening than an experienced midwife would. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Analysis of ground response data at Lotung large-scale soil- structure interaction experiment site

    International Nuclear Information System (INIS)

    Chang, C.Y.; Mok, C.M.; Power, M.S.

    1991-12-01

    The Electric Power Research Institute (EPRI), in cooperation with the Taiwan Power Company (TPC), constructed two models (1/4-scale and 1/2-scale) of a nuclear plant containment structure at a site in Lotung (Tang, 1987), a seismically active region in northeast Taiwan. The models were constructed to gather data for the evaluation and validation of soil-structure interaction (SSI) analysis methodologies. Extensive instrumentation was deployed to record both structural and ground responses at the site during earthquakes. The experiment is generally referred to as the Lotung Large-Scale Seismic Test (LSST). As part of the LSST, two downhole arrays were installed at the site to record ground motions at depths as well as at the ground surface. Structural response and ground response have been recorded for a number of earthquakes (i.e. a total of 18 earthquakes in the period of October 1985 through November 1986) at the LSST site since the completion of the installation of the downhole instruments in October 1985. These data include those from earthquakes having magnitudes ranging from M L 4.5 to M L 7.0 and epicentral distances range from 4.7 km to 77.7 km. Peak ground surface accelerations range from 0.03 g to 0.21 g for the horizontal component and from 0.01 g to 0.20 g for the vertical component. The objectives of the study were: (1) to obtain empirical data on variations of earthquake ground motion with depth; (2) to examine field evidence of nonlinear soil response due to earthquake shaking and to determine the degree of soil nonlinearity; (3) to assess the ability of ground response analysis techniques including techniques to approximate nonlinear soil response to estimate ground motions due to earthquake shaking; and (4) to analyze earth pressures recorded beneath the basemat and on the side wall of the 1/4 scale model structure during selected earthquakes

  3. Ground cross-modal impedance as a tool for analyzing ground/plate interaction and ground wave propagation.

    Science.gov (United States)

    Grau, L; Laulagnet, B

    2015-05-01

    An analytical approach is investigated to model ground-plate interaction based on modal decomposition and the two-dimensional Fourier transform. A finite rectangular plate subjected to flexural vibration is coupled with the ground and modeled with the Kirchhoff hypothesis. A Navier equation represents the stratified ground, assumed infinite in the x- and y-directions and free at the top surface. To obtain an analytical solution, modal decomposition is applied to the structure and a Fourier Transform is applied to the ground. The result is a new tool for analyzing ground-plate interaction to resolve this problem: ground cross-modal impedance. It allows quantifying the added-stiffness, added-mass, and added-damping from the ground to the structure. Similarity with the parallel acoustic problem is highlighted. A comparison between the theory and the experiment shows good matching. Finally, specific cases are investigated, notably the influence of layer depth on plate vibration.

  4. [A Grounded Theory Approach on Nurses' Experience with Workplace Bullying].

    Science.gov (United States)

    Kang, Jiyeon; Yun, Seonyoung

    2016-04-01

    The purpose of this qualitative study was to explore the workplace bullying experience of Korean nurses. Participants were twenty current or former hospital nurses who had experienced workplace bullying. Data were collected through focus group and individual in-depth interviews from February to May, 2015. Theoretical sampling method was applied to the point of theoretical saturation. Transcribed interview contents were analyzed using Corbin and Strauss's grounded theory method. A total of 110 concepts, 48 sub-categories, and 17 categories were identified through the open coding process. As a result of axial coding based on the paradigm model, the central phenomenon of nurses' workplace bullying experience was revealed as 'teaching that has become bullying', and the core category was extracted as 'surviving in love-hate teaching' consisting of a four-step process: confronting reality, trial and error, relationship formation, and settlement. The relationship formation was considered to be the key phase to proceed to the positive settlement phase, and the participants utilized various strategies such as having an open mind, developing human relationships, understanding each other in this phase. The in-depth understanding of the workplace bullying experience has highlighted the importance of effective communication for cultivating desirable human relationships between nurses.

  5. Report of the Interagency Optical Network Testbeds Workshop 2 September 12-14, 2006 NASA Ames Research Center

    Energy Technology Data Exchange (ETDEWEB)

    Joe Mambretti Richard desJardins

    2006-05-01

    A new generation of optical networking services and technologies is rapidly changing the world of communications. National and international networks are implementing optical services to supplement traditional packet routed services. On September 12-14, 2005, the Optical Network Testbeds Workshop 2 (ONT2), an invitation-only forum hosted by the NASA Research and Engineering Network (NREN) and co-sponsored by the Department of Energy (DOE), was held at NASA Ames Research Center in Mountain View, California. The aim of ONT2 was to help the Federal Large Scale Networking Coordination Group (LSN) and its Joint Engineering Team (JET) to coordinate testbed and network roadmaps describing agency and partner organization views and activities for moving toward next generation communication services based on leading edge optical networks in the 3-5 year time frame. ONT2 was conceived and organized as a sequel to the first Optical Network Testbeds Workshop (ONT1, August 2004, www.nren.nasa.gov/workshop7). ONT1 resulted in a series of recommendations to LSN. ONT2 was designed to move beyond recommendations to agree on a series of “actionable objectives” that would proactively help federal and partner optical network testbeds and advanced research and education (R&E) networks to begin incorporating technologies and services representing the next generation of advanced optical networks in the next 1-3 years. Participants in ONT2 included representatives from innovative prototype networks (Panel A), basic optical network research testbeds (Panel B), and production R&D networks (Panels C and D), including “JETnets,” selected regional optical networks (RONs), international R&D networks, commercial network technology and service providers (Panel F), and senior engineering and R&D managers from LSN agencies and partner organizations. The overall goal of ONT2 was to identify and coordinate short and medium term activities and milestones for researching, developing, identifying

  6. GPS and Galileo Developments on Board the International Space Station With the Space Communications and Navigation (SCaN) Testbed

    Science.gov (United States)

    Pozzobon, Oscar; Fantinato, Samuele; Dalla Chiara, Andrea; Gamba, Giovanni; Crisci, Massimo; Giordana, Pietro; Enderle, Werner; Chelmins, David; Sands, Obed S.; Clapper, Carolyn J.; hide

    2016-01-01

    The Space Communications and Navigation (SCaN) is a facility developed by NASA and hosted on board the International Space Station (ISS) on an external truss since 2013.It has the objective of testing navigation and communication experimentations with a Software Defined Radio (SDR) approach, which permits software updates for testing new experimentations.NASA has developed the Space Telecommunications Radio System (STRS) architecture standard for SDRs used in space and ground-based platforms to provide commonality among radio developments to provide enhanced capability. The hardware is equipped with both L band front-end radios and the NASA space network communicates with it using S-band, Ku-band and Ka-band links.In May 2016 Qascom started GARISS (GPS and Galileo Receiver for the ISS), an activity of experimentation in collaboration with ESA and NASA that has the objective to develop and validate the acquisition and processing of combined GPS and Galileo signals on board the ISS SCaN testbed. This paper has the objective to present the mission, and provide preliminary details about the challenges in the design, development and verification of the waveform that will be installed on equipment with limited resources. GARISS is also the first attempt to develop a waveform for the ISS as part of an international collaboration between US and Europe. Although the final mission objective is to target dual frequency processing, initial operations will foresee a single frequency processing. Initial results and trade-off between the two options, as well as the final decision will be presented and discussed. The limited resources on board the SCaN with respect to the challenging requirements to acquire and track contemporaneously two satellite navigation systems, with different modulations and data structure, led to the need to assess the possibility of aiding from ground through the S-band. This option would allow assistance to the space receiver in order to provide

  7. High-Resolution Adaptive Optics Test-Bed for Vision Science

    International Nuclear Information System (INIS)

    Wilks, S.C.; Thomspon, C.A.; Olivier, S.S.; Bauman, B.J.; Barnes, T.; Werner, J.S.

    2001-01-01

    We discuss the design and implementation of a low-cost, high-resolution adaptive optics test-bed for vision research. It is well known that high-order aberrations in the human eye reduce optical resolution and limit visual acuity. However, the effects of aberration-free eyesight on vision are only now beginning to be studied using adaptive optics to sense and correct the aberrations in the eye. We are developing a high-resolution adaptive optics system for this purpose using a Hamamatsu Parallel Aligned Nematic Liquid Crystal Spatial Light Modulator. Phase-wrapping is used to extend the effective stroke of the device, and the wavefront sensing and wavefront correction are done at different wavelengths. Issues associated with these techniques will be discussed

  8. The Youth and Experience of Traffic Accidents (Grounded Theory

    Directory of Open Access Journals (Sweden)

    Sayyed-Muhammad-Hossein Javadi

    2017-01-01

    Full Text Available Background: Traffic accidents are among major causes of death all over the world. In Iran, it has become a social problem, with lots of people involved in; and the youth include the most victims of traffic accidents. Objectives: The main objective of this research is to review the experience of the youth (18–24 years old in Tehran, Iran with traffic accidents, and to develop a model to specify the factors. Methods: This study is based on Grounded Theory, in which a sample group of 50 young people, 18–24 years old, in Tehran, Iran, were selected and interviewed, using stratified purposive and snowball sampling method. Data is mainly collected by interviewing the youth in 7 key topics. To analyze the data, Grounded Theory is used through production of themes, components and concepts. Results: There are 11 general components for traffic accidents according to the ideas of the youth which will come in 3 categories including: individual factors (emotions, sensory-motor skills, and physical-mental health; environmental factors (road and traffic problems, a companion, using cellphone, or front individual, including carless drivers or passersby; and underlying factors (gender, legal and cultural infrastructures. And finally, the core category of carelessness, which is the leading cause in traffic accidents.    Conclusion: The findings indicate that a chain of various factors may cause traffic accidents with lots of devastating consequences. It is therefore necessary to modify driving culture, to internalize the attitude of caution, to use polyhedral strategies, and to apply them all correctly.

  9. Liquid Structures and Physical Properties -- Ground Based Studies for ISS Experiments

    Science.gov (United States)

    Kelton, K. F.; Bendert, J. C.; Mauro, N. A.

    2012-01-01

    Studies of electrostatically-levitated supercooled liquids have demonstrated strong short- and medium-range ordering in transition metal and alloy liquids, which can influence phase transitions like crystal nucleation and the glass transition. The structure is also related to the liquid properties. Planned ISS experiments will allow a deeper investigation of these results as well as the first investigations of a new type of coupling in crystal nucleation in primary crystallizing liquids, resulting from a linking of the stochastic processes of diffusion with interfacial-attachment. A brief description of the techniques used for ground-based studies and some results relevant to planned ISS investigations are discussed.

  10. Microgrid testbeds around the world: State of art

    International Nuclear Information System (INIS)

    Hossain, Eklas; Kabalci, Ersan; Bayindir, Ramazan; Perez, Ronald

    2014-01-01

    Highlights: • A detail discussion on microgrid project around the world such as North American, Europe, and Japan. • Key benefits of microgrid, issues with on-site generation, features. • Why we need distributed generation system with a brief introduction. • Distributed generation technologies with cost analysis. • The overview on existing distribution network. - Abstract: This paper deals with the recent evolution of microgrids being used around the world in real life applications as well as laboratory application for research. This study is intended to introduce the subject by reviewing the components level, structure and types of microgrid applications installed as a plant or modeled as a simulation environment. The paper also presents a survey regarding published papers on why the microgrid is required, and what the components and control systems are which constitute the actual microgrid studies. It leads the researcher to see the microgrid in terms of the actual bigger picture of today and creates a new outlook about the potential developments. Additionally, comparison of microgrids in various regions based on several parameters allows researchers to define the required criteria and features of a special microgrid that is chosen for a particular scenario. The authors of this paper also tabulated all the necessary information about microgrids, and proposed a standard microgrid for better power quality and optimizing energy generation. Consequently, it is focused on inadequate knowledge and technology gaps in the power system field with regards to the future, and it is this which has been illustrated for the reader. The existing microgrid testbeds all around the world have been studied and analyzed and several of them are explained as an example in this study. Later, those investigated distribution systems are classified based on region (North America, Europe and Asia) and, as presented in literature, a significant amount of deviation has been found

  11. Development of research reactor simulator and its application to dynamic test-bed

    International Nuclear Information System (INIS)

    Kwon, Kee-Choon; Baang, Dane; Park, Jae-Chang; Lee, Seung-Wook; Bae, Sung Won

    2014-01-01

    We developed a real-time simulator for 'High-flux Advanced Neutron Application ReactOr (HANARO), and the Jordan Research and Training Reactor (JRTR). The main purpose of this simulator is operator training, but we modified this simulator into a dynamic test-bed (DTB) to test the functions and dynamic control performance of reactor regulating system (RRS) in HANARO or JRTR before installation. The simulator hardware consists of a host computer, 6 operator stations, a network switch, and a large display panel. The software includes a mathematical model that implements plant dynamics in real-time, an instructor station module that manages user instructions, and a human machine interface module. The developed research reactor simulators are installed in the Korea Atomic Energy Research Institute nuclear training center for reactor operator training. To use the simulator as a dynamic test-bed, the reactor regulating system modeling software of the simulator was replaced by actual RRS cabinet, and was interfaced using a hard-wired and network-based interface. RRS cabinet generates control signals for reactor power control based on the various feedback signals from DTB, and the DTB runs plant dynamics based on the RRS control signals. Thus the Hardware-In-the-Loop Simulation between RRS and the emulated plant (DTB) has been implemented and tested in this configuration. The test result shows that the developed DTB and actual RRS cabinet works together simultaneously resulting in quite good dynamic control performances. (author)

  12. Ground water pollution by roof runoff infiltration evidenced with multi-tracer experiments.

    Science.gov (United States)

    Ammann, Adrian A; Hoehn, Eduard; Koch, Sabine

    2003-03-01

    The infiltration of urban roof runoff into well permeable subsurface material may have adverse effects on the ground water quality and endanger drinking water resources. Precipitation water from three different roofs of an industrial complex was channelled to a pit and infiltrated into a perialpine glaciofluvial gravel-and-sand aquifer. A shaft was constructed at the bottom of the pit and equipped with an array of TDR probes, lysimeters and suction cups that allowed measuring and sampling soil water at different depths. A fast infiltration flow was observed during natural rainfall events and during artificial infiltration experiments. For a better understanding of the behaviour of contaminants, experiments were conducted with cocktails of compounds of different reactivity (ammonium, strontium, atratone) and of non-reactive tracers (uranine, bromide, naphthionate), which represent different classes of pollutants. The experiment identified cation exchange reactions influencing the composition of the infiltrating water. These processes occurred under preferential flow conditions in macropores of the material. Measuring concentration changes under the controlled inflow of tracer experiments, the pollution potential was found to be high. Non-reactive tracers exhibited fast breakthrough and little sorption.

  13. Implementation of Motion Simulation Software and Visual-Auditory Electronics for Use in a Low Gravity Robotic Testbed

    Science.gov (United States)

    Martin, William Campbell

    2011-01-01

    The Jet Propulsion Laboratory (JPL) is developing the All-Terrain Hex-Limbed Extra-Terrestrial Explorer (ATHLETE) to assist in manned space missions. One of the proposed targets for this robotic vehicle is a near-Earth asteroid (NEA), which typically exhibit a surface gravity of only a few micro-g. In order to properly test ATHLETE in such an environment, the development team has constructed an inverted Stewart platform testbed that acts as a robotic motion simulator. This project focused on creating physical simulation software that is able to predict how ATHLETE will function on and around a NEA. The corresponding platform configurations are calculated and then passed to the testbed to control ATHLETE's motion. In addition, imitation attitude, imitation attitude control thrusters were designed and fabricated for use on ATHLETE. These utilize a combination of high power LEDs and audio amplifiers to provide visual and auditory cues that correspond to the physics simulation.

  14. The Fourier-Kelvin Stellar Interferometer (FKSI) Nulling Testbed II: Closed-loop Path Length Metrology And Control Subsystem

    Science.gov (United States)

    Frey, B. J.; Barry, R. K.; Danchi, W. C.; Hyde, T. T.; Lee, K. Y.; Martino, A. J.; Zuray, M. S.

    2006-01-01

    The Fourier-Kelvin Stellar Interferometer (FKSI) is a mission concept for an imaging and nulling interferometer in the near to mid-infrared spectral region (3-8 microns), and will be a scientific and technological pathfinder for upcoming missions including TPF-I/DARWIN, SPECS, and SPIRIT. At NASA's Goddard Space Flight Center, we have constructed a symmetric Mach-Zehnder nulling testbed to demonstrate techniques and algorithms that can be used to establish and maintain the 10(exp 4) null depth that will be required for such a mission. Among the challenges inherent in such a system is the ability to acquire and track the null fringe to the desired depth for timescales on the order of hours in a laboratory environment. In addition, it is desirable to achieve this stability without using conventional dithering techniques. We describe recent testbed metrology and control system developments necessary to achieve these goals and present our preliminary results.

  15. A numerical testbed for remote sensing of aerosols, and its demonstration for evaluating retrieval synergy from a geostationary satellite constellation of GEO-CAPE and GOES-R

    International Nuclear Information System (INIS)

    Wang, Jun; Xu, Xiaoguang; Ding, Shouguo; Zeng, Jing; Spurr, Robert; Liu, Xiong; Chance, Kelly; Mishchenko, Michael

    2014-01-01

    We present a numerical testbed for remote sensing of aerosols, together with a demonstration for evaluating retrieval synergy from a geostationary satellite constellation. The testbed combines inverse (optimal-estimation) software with a forward model containing linearized code for computing particle scattering (for both spherical and non-spherical particles), a kernel-based (land and ocean) surface bi-directional reflectance facility, and a linearized radiative transfer model for polarized radiance. Calculation of gas absorption spectra uses the HITRAN (HIgh-resolution TRANsmission molecular absorption) database of spectroscopic line parameters and other trace species cross-sections. The outputs of the testbed include not only the Stokes 4-vector elements and their sensitivities (Jacobians) with respect to the aerosol single scattering and physical parameters (such as size and shape parameters, refractive index, and plume height), but also DFS (Degree of Freedom for Signal) values for retrieval of these parameters. This testbed can be used as a tool to provide an objective assessment of aerosol information content that can be retrieved for any constellation of (planned or real) satellite sensors and for any combination of algorithm design factors (in terms of wavelengths, viewing angles, radiance and/or polarization to be measured or used). We summarize the components of the testbed, including the derivation and validation of analytical formulae for Jacobian calculations. Benchmark calculations from the forward model are documented. In the context of NASA's Decadal Survey Mission GEO-CAPE (GEOstationary Coastal and Air Pollution Events), we demonstrate the use of the testbed to conduct a feasibility study of using polarization measurements in and around the O 2 A band for the retrieval of aerosol height information from space, as well as an to assess potential improvement in the retrieval of aerosol fine and coarse mode aerosol optical depth (AOD) through the

  16. Save Maritime Systems Testbed

    Directory of Open Access Journals (Sweden)

    Bolles André

    2014-06-01

    Full Text Available ‘Safe voyage from berth to berth’ — this is the goal of all e-navigation strains, driven by new technologies, new infrastructures and new organizational structures on bridge, on shore as well as in the cloud. To facilitate these efforts suitable engineering and safety/risk assessment methods have to be applied. Understanding maritime transportation as a sociotechnical system allows system engineering methods to be applied. Formal and simulation based verification and validation of e-navigation technologies are important methods to obtain system safety and reliability. The modelling and simulation toolset HAGGIS provides methods for system specification and formal risk analysis. It provides a modelling framework for processes, fault trees and generic hazard specification and a physical world and maritime traffic simulation system. HAGGIS is accompanied by the physical test bed LABSKAUS which implements a reference port and waterway. Additionally, it contains an experimental Vessel Traffic Services (VTS implementation and a mobile integrated bridge enabling in situ experiments for technology evaluation, testing, ground research and demonstration. This paper describes an integrated seamless approach for developing new e-navigation technologies starting with virtual simulation based assessment and ending in physical real world demonstrations.

  17. A Numerical Testbed for Remote Sensing of Aerosols, and its Demonstration for Evaluating Retrieval Synergy from a Geostationary Satellite Constellation of GEO-CAPE and GOES-R

    Science.gov (United States)

    Wang, Jun; Xu, Xiaoguang; Ding, Shouguo; Zeng, Jing; Spurr, Robert; Liu, Xiong; Chance, Kelly; Mishchenko, Michael I.

    2014-01-01

    We present a numerical testbed for remote sensing of aerosols, together with a demonstration for evaluating retrieval synergy from a geostationary satellite constellation. The testbed combines inverse (optimal-estimation) software with a forward model containing linearized code for computing particle scattering (for both spherical and non-spherical particles), a kernel-based (land and ocean) surface bi-directional reflectance facility, and a linearized radiative transfer model for polarized radiance. Calculation of gas absorption spectra uses the HITRAN (HIgh-resolution TRANsmission molecular absorption) database of spectroscopic line parameters and other trace species cross-sections. The outputs of the testbed include not only the Stokes 4-vector elements and their sensitivities (Jacobians) with respect to the aerosol single scattering and physical parameters (such as size and shape parameters, refractive index, and plume height), but also DFS (Degree of Freedom for Signal) values for retrieval of these parameters. This testbed can be used as a tool to provide an objective assessment of aerosol information content that can be retrieved for any constellation of (planned or real) satellite sensors and for any combination of algorithm design factors (in terms of wavelengths, viewing angles, radiance and/or polarization to be measured or used). We summarize the components of the testbed, including the derivation and validation of analytical formulae for Jacobian calculations. Benchmark calculations from the forward model are documented. In the context of NASA's Decadal Survey Mission GEOCAPE (GEOstationary Coastal and Air Pollution Events), we demonstrate the use of the testbed to conduct a feasibility study of using polarization measurements in and around the O2 A band for the retrieval of aerosol height information from space, as well as an to assess potential improvement in the retrieval of aerosol fine and coarse mode aerosol optical depth (AOD) through the

  18. NN-SITE: A remote monitoring testbed facility

    International Nuclear Information System (INIS)

    Kadner, S.; White, R.; Roman, W.; Sheely, K.; Puckett, J.; Ystesund, K.

    1997-01-01

    DOE, Aquila Technologies, LANL and SNL recently launched collaborative efforts to create a Non-Proliferation Network Systems Integration and Test (NN-Site, pronounced N-Site) facility. NN-Site will focus on wide area, local area, and local operating level network connectivity including Internet access. This facility will provide thorough and cost-effective integration, testing and development of information connectivity among diverse operating systems and network topologies prior to full-scale deployment. In concentrating on instrument interconnectivity, tamper indication, and data collection and review, NN-Site will facilitate efforts of equipment providers and system integrators in deploying systems that will meet nuclear non-proliferation and safeguards objectives. The following will discuss the objectives of ongoing remote monitoring efforts, as well as the prevalent policy concerns. An in-depth discussion of the Non-Proliferation Network Systems Integration and Test facility (NN-Site) will illuminate the role that this testbed facility can perform in meeting the objectives of remote monitoring efforts, and its potential contribution in promoting eventual acceptance of remote monitoring systems in facilities worldwide

  19. An ODMG-compatible testbed architecture for scalable management and analysis of physics data

    International Nuclear Information System (INIS)

    Malon, D.M.; May, E.N.

    1997-01-01

    This paper describes a testbed architecture for the investigation and development of scalable approaches to the management and analysis of massive amounts of high energy physics data. The architecture has two components: an interface layer that is compliant with a substantial subset of the ODMG-93 Version 1.2 specification, and a lightweight object persistence manager that provides flexible storage and retrieval services on a variety of single- and multi-level storage architectures, and on a range of parallel and distributed computing platforms

  20. Ground-based simulation of telepresence for materials science experiments. [remote viewing and control of processes aboard Space Station

    Science.gov (United States)

    Johnston, James C.; Rosenthal, Bruce N.; Bonner, Mary JO; Hahn, Richard C.; Herbach, Bruce

    1989-01-01

    A series of ground-based telepresence experiments have been performed to determine the minimum video frame rate and resolution required for the successive performance of materials science experiments in space. The approach used is to simulate transmission between earth and space station with transmission between laboratories on earth. The experiments include isothermal dendrite growth, physical vapor transport, and glass melting. Modifications of existing apparatus, software developed, and the establishment of an inhouse network are reviewed.

  1. A Grounded Theory of Preservice Music Educators' Lesson Planning Processes within Field Experience Methods Courses

    Science.gov (United States)

    Parker, Elizabeth Cassidy; Bond, Vanessa L.; Powell, Sean R.

    2017-01-01

    The purpose of this grounded theory study was to understand the process of field experience lesson planning for preservice music educators enrolled in choral, general, and instrumental music education courses within three university contexts. Data sources included multiple interviews, written responses, and field texts from 42 participants. Four…

  2. NASA Robotic Neurosurgery Testbed

    Science.gov (United States)

    Mah, Robert

    1997-01-01

    The detection of tissue interface (e.g., normal tissue, cancer, tumor) has been limited clinically to tactile feedback, temperature monitoring, and the use of a miniature ultrasound probe for tissue differentiation during surgical operations, In neurosurgery, the needle used in the standard stereotactic CT or MRI guided brain biopsy provides no information about the tissue being sampled. The tissue sampled depends entirely upon the accuracy with which the localization provided by the preoperative CT or MRI scan is translated to the intracranial biopsy site. In addition, no information about the tissue being traversed by the needle (e.g., a blood vessel) is provided. Hemorrhage due to the biopsy needle tearing a blood vessel within the brain is the most devastating complication of stereotactic CT/MRI guided brain biopsy. A robotic neurosurgery testbed has been developed at NASA Ames Research Center as a spin-off of technologies from space, aeronautics and medical programs. The invention entitled "Robotic Neurosurgery Leading to Multimodality Devices for Tissue Identification" is nearing a state ready for commercialization. The devices will: 1) improve diagnostic accuracy and precision of general surgery, with near term emphasis on stereotactic brain biopsy, 2) automate tissue identification, with near term emphasis on stereotactic brain biopsy, to permit remote control of the procedure, and 3) reduce morbidity for stereotactic brain biopsy. The commercial impact from this work is the potential development of a whole new generation of smart surgical tools to increase the safety, accuracy and efficiency of surgical procedures. Other potential markets include smart surgical tools for tumor ablation in neurosurgery, general exploratory surgery, prostate cancer surgery, and breast cancer surgery.

  3. A hardware-in-the-loop simulation program for ground-based radar

    Science.gov (United States)

    Lam, Eric P.; Black, Dennis W.; Ebisu, Jason S.; Magallon, Julianna

    2011-06-01

    A radar system created using an embedded computer system needs testing. The way to test an embedded computer system is different from the debugging approaches used on desktop computers. One way to test a radar system is to feed it artificial inputs and analyze the outputs of the radar. More often, not all of the building blocks of the radar system are available to test. This will require the engineer to test parts of the radar system using a "black box" approach. A common way to test software code on a desktop simulation is to use breakpoints so that is pauses after each cycle through its calculations. The outputs are compared against the values that are expected. This requires the engineer to use valid test scenarios. We will present a hardware-in-the-loop simulator that allows the embedded system to think it is operating with real-world inputs and outputs. From the embedded system's point of view, it is operating in real-time. The hardware in the loop simulation is based on our Desktop PC Simulation (PCS) testbed. In the past, PCS was used for ground-based radars. This embedded simulation, called Embedded PCS, allows a rapid simulated evaluation of ground-based radar performance in a laboratory environment.

  4. Optical testbed for the LISA phasemeter

    Science.gov (United States)

    Schwarze, T. S.; Fernández Barranco, G.; Penkert, D.; Gerberding, O.; Heinzel, G.; Danzmann, K.

    2016-05-01

    The planned spaceborne gravitational wave detector LISA will allow the detection of gravitational waves at frequencies between 0.1 mHz and 1 Hz. A breadboard model for the metrology system aka the phasemeter was developed in the scope of an ESA technology development project by a collaboration between the Albert Einstein Institute, the Technical University of Denmark and the Danish industry partner Axcon Aps. It in particular provides the electronic readout of the main interferometer phases besides auxiliary functions. These include clock noise transfer, ADC pilot tone correction, inter-satellite ranging and data transfer. Besides in LISA, the phasemeter can also be applied in future satellite geodesy missions. Here we show the planning and advances in the implementation of an optical testbed for the full metrology chain. It is based on an ultra-stable hexagonal optical bench. This bench allows the generation of three unequal heterodyne beatnotes with a zero phase combination, thus providing the possibility to probe the phase readout for non-linearities in an optical three signal test. Additionally, the utilization of three independent phasemeters will allow the testing of the auxiliary functions. Once working, components can individually be replaced with flight-qualified hardware in this setup.

  5. Optical testbed for the LISA phasemeter

    International Nuclear Information System (INIS)

    Schwarze, T S; Fernández Barranco, G; Penkert, D; Gerberding, O; Heinzel, G; Danzmann, K

    2016-01-01

    The planned spaceborne gravitational wave detector LISA will allow the detection of gravitational waves at frequencies between 0.1 mHz and 1 Hz. A breadboard model for the metrology system aka the phasemeter was developed in the scope of an ESA technology development project by a collaboration between the Albert Einstein Institute, the Technical University of Denmark and the Danish industry partner Axcon Aps. It in particular provides the electronic readout of the main interferometer phases besides auxiliary functions. These include clock noise transfer, ADC pilot tone correction, inter-satellite ranging and data transfer. Besides in LISA, the phasemeter can also be applied in future satellite geodesy missions. Here we show the planning and advances in the implementation of an optical testbed for the full metrology chain. It is based on an ultra-stable hexagonal optical bench. This bench allows the generation of three unequal heterodyne beatnotes with a zero phase combination, thus providing the possibility to probe the phase readout for non-linearities in an optical three signal test. Additionally, the utilization of three independent phasemeters will allow the testing of the auxiliary functions. Once working, components can individually be replaced with flight-qualified hardware in this setup. (paper)

  6. Status Update on the GPM Ground Validation Iowa Flood Studies (IFloodS) Field Experiment

    Science.gov (United States)

    Petersen, Walt; Krajewski, Witold

    2013-04-01

    The overarching objective of integrated hydrologic ground validation activities supporting the Global Precipitation Measurement Mission (GPM) is to provide better understanding of the strengths and limitations of the satellite products, in the context of hydrologic applications. To this end, the GPM Ground Validation (GV) program is conducting the first of several hydrology-oriented field efforts: the Iowa Flood Studies (IFloodS) experiment. IFloodS will be conducted in the central to northeastern part of Iowa in Midwestern United States during the months of April-June, 2013. Specific science objectives and related goals for the IFloodS experiment can be summarized as follows: 1. Quantify the physical characteristics and space/time variability of rain (rates, DSD, process/"regime") and map to satellite rainfall retrieval uncertainty. 2. Assess satellite rainfall retrieval uncertainties at instantaneous to daily time scales and evaluate propagation/impact of uncertainty in flood-prediction. 3. Assess hydrologic predictive skill as a function of space/time scales, basin morphology, and land use/cover. 4. Discern the relative roles of rainfall quantities such as rate and accumulation as compared to other factors (e.g. transport of water in the drainage network) in flood genesis. 5. Refine approaches to "integrated hydrologic GV" concept based on IFloodS experiences and apply to future GPM Integrated GV field efforts. These objectives will be achieved via the deployment of the NASA NPOL S-band and D3R Ka/Ku-band dual-polarimetric radars, University of Iowa X-band dual-polarimetric radars, a large network of paired rain gauge platforms with attendant soil moisture and temperature probes, a large network of both 2D Video and Parsivel disdrometers, and USDA-ARS gauge and soil-moisture measurements (in collaboration with the NASA SMAP mission). The aforementioned measurements will be used to complement existing operational WSR-88D S-band polarimetric radar measurements

  7. Segmented Aperture Interferometric Nulling Testbed (SAINT) II: component systems update

    Science.gov (United States)

    Hicks, Brian A.; Bolcar, Matthew R.; Helmbrecht, Michael A.; Petrone, Peter; Burke, Elliot; Corsetti, James; Dillon, Thomas; Lea, Andrew; Pellicori, Samuel; Sheets, Teresa; Shiri, Ron; Agolli, Jack; DeVries, John; Eberhardt, Andrew; McCabe, Tyler

    2017-09-01

    This work presents updates to the coronagraph and telescope components of the Segmented Aperture Interferometric Nulling Testbed (SAINT). The project pairs an actively-controlled macro-scale segmented mirror with the Visible Nulling Coronagraph (VNC) towards demonstrating capabilities for the future space observatories needed to directly detect and characterize a significant sample of Earth-sized worlds around nearby stars in the quest for identifying those which may be habitable and possibly harbor life. Efforts to improve the VNC wavefront control optics and mechanisms towards repeating narrowband results are described. A narrative is provided for the design of new optical components aimed at enabling broadband performance. Initial work with the hardware and software interface for controlling the segmented telescope mirror is also presented.

  8. Solar House Obdach: experiences with a solar ground-coupled storage system

    Energy Technology Data Exchange (ETDEWEB)

    Bruck, M; Blum, P; Held, E; Aranovitch, E; Hardacre, A G; Ofverholm, E [eds.

    1982-09-14

    Within the framework of the Solar House Obdach-project, a system consisting of a ground heat exchanger, a low-temperature collector, a water-glycol/water heat pump and a low-temperature heating system was examined with regard to its suitability as only heat source of a house. With the design chosen (1 m/sup 2/ ground collector area and 0.3 m/sup 2/ low-temperature collector area per 80 W load), a seasonal performance factor of 2.83 could be obtained. About 40% of the low-temperature heat supplied to the heat pump were delivered directly or indirectly (by means of short-term storage in the ground) by the low-temperature collector, whereas about 60% came from the natural sources of energy of the ground (air heat, radiation, precipitation, ground water and slope water). The results obtained are used to verify and improve a computer model design program for ground collectors and ground-coupled storage systems which should help to optimize the design of solar plants, particularly under difficult conditions.

  9. Photovoltaic Shading Testbed for Module-Level Power Electronics: 2016 Performance Data Update

    Energy Technology Data Exchange (ETDEWEB)

    Deline, Chris [National Renewable Energy Lab. (NREL), Golden, CO (United States); Meydbray, Jenya [PV Evolution Labs (PVEL), Davis, CA (United States); Donovan, Matt [PV Evolution Labs (PVEL), Davis, CA (United States)

    2016-09-01

    The 2012 NREL report 'Photovoltaic Shading Testbed for Module-Level Power Electronics' provides a standard methodology for estimating the performance benefit of distributed power electronics under partial shading conditions. Since the release of the report, experiments have been conducted for a number of products and for different system configurations. Drawing from these experiences, updates to the test and analysis methods are recommended. Proposed changes in data processing have the benefit of reducing the sensitivity to measurement errors and weather variability, as well as bringing the updated performance score in line with measured and simulated values of the shade recovery benefit of distributed PV power electronics. Also, due to the emergence of new technologies including sub-module embedded power electronics, the shading method has been extended to include power electronics that operate at a finer granularity than the module level. An update to the method is proposed to account for these emerging technologies that respond to shading differently than module-level devices. The partial shading test remains a repeatable test procedure that attempts to simulate shading situations as would be experienced by typical residential or commercial rooftop photovoltaic (PV) systems. Performance data for multiple products tested using this method are discussed, based on equipment from Enphase, Solar Edge, Maxim Integrated and SMA. In general, the annual recovery of shading losses from the module-level electronics evaluated is 25-35%, with the major difference between different trials being related to the number of parallel strings in the test installation rather than differences between the equipment tested. Appendix D data has been added in this update.

  10. Design of a nickel-hydrogen battery simulator for the NASA EOS testbed

    Science.gov (United States)

    Gur, Zvi; Mang, Xuesi; Patil, Ashok R.; Sable, Dan M.; Cho, Bo H.; Lee, Fred C.

    1992-01-01

    The hardware and software design of a nickel-hydrogen (Ni-H2) battery simulator (BS) with application to the NASA Earth Observation System (EOS) satellite is presented. The battery simulator is developed as a part of a complete testbed for the EOS satellite power system. The battery simulator involves both hardware and software components. The hardware component includes the capability of sourcing and sinking current at a constant programmable voltage. The software component includes the capability of monitoring the battery's ampere-hours (Ah) and programming the battery voltage according to an empirical model of the nickel-hydrogen battery stored in a computer.

  11. Traditional behaviour and fidelity to caribou calving grounds by barren-ground caribou

    Directory of Open Access Journals (Sweden)

    Anne Gunn

    1986-06-01

    Full Text Available Evidence for the fidelity of female barren-ground caribou (Rangifer tarandus spp. of each herd to specific calving grounds is convincing. Involvement of learned behaviour in the annual return of those cows to the same calving grounds implies such actions are a form of «traditional» behaviour. Even wide variations in population size have not yet knowingly led to marked changes in size or location of calving grounds or prolonged abandonment of established ones. Rarely is the adoption of new calving grounds reported and emigration to another herd's calving ground or interchange between calving grounds has not yet been unequivocally documented. The calving experience of individual caribou and environmental pressures may modify the cow's use patterns of her calving grounds. The current definition of herds based on traditional calving grounds may require modification, if increasing caribou numbers result in changes in traditions. However, current data do not contradict either the fidelity to traditional calving grounds or the concept of herd identity based on that fidelity.

  12. Experiences of antidepressant medication and cognitive-behavioural therapy for depression: a grounded theory study.

    Science.gov (United States)

    Bayliss, Paul; Holttum, Sue

    2015-09-01

    To develop a preliminary model of the experiences of people undergoing combined treatment with antidepressant medication and cognitive-behavioural therapy (CBT) for depression. The study used a qualitative methodology informed by grounded theory. Participants were 12 adults who had received treatment with antidepressant medication and CBT for depression. Participants engaged in a semistructured interview about their experiences. Interviews were transcribed and analysed using components of grounded theory methodology. Medication was often seen as an initial aid to surviving a crisis. Staying on medication longer term resulted in some participants feeling caught in a 'drug loop'. Feeling that medication was unhelpful or actively harmful could contribute to participants seeking CBT. Medics also offered information on CBT and acted as gatekeepers, meaning that negotiation was sometimes necessary. CBT was described as a process of being guided towards skilled self-management. Occasionally, participants felt that medication had facilitated CBT at one or more stages. Conversely, developing skilled self-management through CBT could reduce feelings of dependency on medication and affect several of the other elements maintaining the 'drug loop'. Antidepressant medication and CBT are perceived and experienced differently, with CBT often being seen as an alternative to medication, or even as a means to discontinue medication. Service users' experiences and beliefs about medication may thus affect their engagement and goals in CBT, and it may be important for therapists to consider this. Practitioners who prescribe medication should ensure that they also provide information on the availability and appropriateness of CBT, and engage in an open dialogue about treatment options. CBT practitioners should explore aspects of clients' experiences and beliefs about medication. This would particularly include clients' experiences of the effects of medication, their beliefs about

  13. Monitoring Ground Subsidence in Hong Kong via Spaceborne Radar: Experiments and Validation

    Directory of Open Access Journals (Sweden)

    Yuxiao Qin

    2015-08-01

    Full Text Available The persistent scatterers interferometry (PSI technique is gradually becoming known for its capability of providing up to millimeter accuracy of measurement on ground displacement. Nevertheless, there is still quite a good amount of doubt regarding its correctness or accuracy. In this paper, we carried out an experiment corroborating the capability of the PSI technique with the help of a traditional survey method in the urban area of Hong Kong, China. Seventy three TerraSAR-X (TSX and TanDEM-X (TDX images spanning over four years are used for the data process. There are three aims of this study. The first is to generate a displacement map of urban Hong Kong and to check for spots with possible ground movements. This information will be provided to the local surveyors so that they can check these specific locations. The second is to validate if the accuracy of the PSI technique can indeed reach the millimeter level in this real application scenario. For validating the accuracy of PSI, four corner reflectors (CR were installed at a construction site on reclaimed land in Hong Kong. They were manually moved up or down by a few to tens of millimeters, and the value derived from the PSI analysis was compared to the true value. The experiment, carried out in unideal conditions, nevertheless proved undoubtedly that millimeter accuracy can be achieved by the PSI technique. The last is to evaluate the advantages and limitations of the PSI technique. Overall, the PSI technique can be extremely useful if used in collaboration with other techniques, so that the advantages can be highlighted and the drawbacks avoided.

  14. Integration of advanced teleoperation technologies for control of space robots

    Science.gov (United States)

    Stagnaro, Michael J.

    1993-01-01

    Teleoperated robots require one or more humans to control actuators, mechanisms, and other robot equipment given feedback from onboard sensors. To accomplish this task, the human or humans require some form of control station. Desirable features of such a control station include operation by a single human, comfort, and natural human interfaces (visual, audio, motion, tactile, etc.). These interfaces should work to maximize performance of the human/robot system by streamlining the link between human brain and robot equipment. This paper describes development of a control station testbed with the characteristics described above. Initially, this testbed will be used to control two teleoperated robots. Features of the robots include anthropomorphic mechanisms, slaving to the testbed, and delivery of sensory feedback to the testbed. The testbed will make use of technologies such as helmet mounted displays, voice recognition, and exoskeleton masters. It will allow tor integration and testing of emerging telepresence technologies along with techniques for coping with control link time delays. Systems developed from this testbed could be applied to ground control of space based robots. During man-tended operations, the Space Station Freedom may benefit from ground control of IVA or EVA robots with science or maintenance tasks. Planetary exploration may also find advanced teleoperation systems to be very useful.

  15. A Functional Neuroimaging Analysis of the Trail Making Test-B: Implications for Clinical Application

    Directory of Open Access Journals (Sweden)

    Mark D. Allen

    2011-01-01

    Full Text Available Recent progress has been made using fMRI as a clinical assessment tool, often employing analogues of traditional “paper and pencil” tests. The Trail Making Test (TMT, popular for years as a neuropsychological exam, has been largely ignored in the realm of neuroimaging, most likely because its physical format and administration does not lend itself to straightforward adaptation as an fMRI paradigm. Likewise, there is relatively more ambiguity about the neural systems associated with this test than many other tests of comparable clinical use. In this study, we describe an fMRI version of Trail Making Test-B (TMTB that maintains the core functionality of the TMT while optimizing its use for both research and clinical settings. Subjects (N = 32 were administered the Functional Trail Making Test-B (f-TMTB. Brain region activations elicited by the f-TMTB were consistent with expectations given by prior TMT neurophysiological studies, including significant activations in the ventral and dorsal visual pathways and the medial pre-supplementary motor area. The f-TMTB was further evaluated for concurrent validity with the traditional TMTB using an additional sample of control subjects (N = 100. Together, these results support the f-TMTB as a viable neuroimaging adaptation of the TMT that is optimized to evoke maximally robust fMRI activation with minimal time and equipment requirements.

  16. Review: Ina-Maria Greverus, Sharon MacDonald, Regina Romhild, Gisela Welz & Helena Wullf (Eds. (2002. Stability Upon Shifting Ground: Review Note of Shifting Grounds: Experiments in Doing Ethnography

    Directory of Open Access Journals (Sweden)

    Robin M. Boylorn

    2005-09-01

    Full Text Available This review is written in response to "Shifting Grounds: Experiments in Doing Ethno­graphy," a volume of the Anthropological Journal on European Cultures. This review cites the history and implications of ethnography as a methodology within various academic disciplines while praising the authors within this text for their contributions to various ways of "doing ethnography." By investi­gating and considering the body as an ethno­graphic site where life and stories are performed and em­bodied, this article considers the varying ways the authors respond to experimental and performative ethnography while applying it to relevant and current issues within anthropology. By engaging both the anthropological and historical turn of ethnography, this book thematically discusses the mobility of fieldwork, time, space, multi-locality, tour­ism, and tradition/culture. Shifting Grounds does not only offer experiments in doing ethnography, it also offers alternatives for doing ethnography. URN: urn:nbn:de:0114-fqs0503175

  17. 30 CFR 57.3360 - Ground support use.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Ground support use. 57.3360 Section 57.3360... and Support-Underground Only § 57.3360 Ground support use. Ground support shall be used where ground conditions, or mining experience in similar ground conditions in the mine, indicate that it is necessary...

  18. Evaporation from bare ground with different water-table depths based on an in-situ experiment in Ordos Plateau, China

    Science.gov (United States)

    Zhang, Zaiyong; Wang, Wenke; Wang, Zhoufeng; Chen, Li; Gong, Chengcheng

    2018-03-01

    The dynamic processes of ground evaporation are complex and are related to a multitude of factors such as meteorological influences, water-table depth, and materials in the unsaturated zone. To investigate ground evaporation from a homogeneous unsaturated zone, an in-situ experiment was conducted in Ordos Plateau of China. Two water-table depths were chosen to explore the water movement in the unsaturated zone and ground evaporation. Based on the experimental and calculated results, it was revealed that (1) bare ground evaporation is an atmospheric-limited stage for the case of water-table depth being close to the capillary height; (2) the bare ground evaporation is a water-storage-limited stage for the case of water-table depth being beyond the capillary height; (3) groundwater has little effect on ground-surface evaporation when the water depth is larger than the capillary height; and (4) ground evaporation is greater at nighttime than that during the daytime; and (5) a liquid-vapor interaction zone at nearly 20 cm depth is found, in which there exists a downward vapor flux on sunny days, leading to an increasing trend of soil moisture between 09:00 to 17:00; the maximum value is reached at midday. The results of this investigation are useful to further understand the dynamic processes of ground evaporation in arid areas.

  19. dc readout experiment at the Caltech 40m prototype interferometer

    International Nuclear Information System (INIS)

    Ward, R L; Adhikari, R; Abbott, B; Abbott, R; Bork, R; Fricke, T; Heefner, J; Ivanov, A; Miyakawa, O; Smith, M; Taylor, R; Vass, S; Waldman, S; Weinstein, A; Barron, D; Frolov, V; McKenzie, K; Slagmolen, B

    2008-01-01

    The Laser Interferometer Gravitational Wave Observatory (LIGO) operates a 40m prototype interferometer on the Caltech campus. The primary mission of the prototype is to serve as an experimental testbed for upgrades to the LIGO interferometers and for gaining experience with advanced interferometric techniques, including detuned resonant sideband extraction (i.e. signal recycling) and dc readout (optical homodyne detection). The former technique will be employed in Advanced LIGO, and the latter in both Enhanced and Advanced LIGO. Using dc readout for gravitational wave signal extraction has several technical advantages, including reduced laser and oscillator noise couplings as well as reduced shot noise, when compared to the traditional rf readout technique (optical heterodyne detection) currently in use in large-scale ground-based interferometric gravitational wave detectors. The Caltech 40m laboratory is currently prototyping a dc readout system for a fully suspended interferometric gravitational wave detector. The system includes an optical filter cavity at the interferometer's output port, and the associated controls and optics to ensure that the filter cavity is optimally coupled to the interferometer. We present the results of measurements to characterize noise couplings in rf and dc readout using this system

  20. An information technology enabled sustainability test-bed (ITEST) for occupancy detection through an environmental sensing network

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Bing; Lam, Khee Poh; Zhang, Rui; Chiou, Yun-Shang [Center for Building Performance and Diagnostics, Carnegie Mellon University, Pittsburgh, PA 15213 (United States); Andrews, Burton; Hoeynck, Michael; Benitez, Diego [Research and Technology Center, Robert BOSCH LLC, Pittsburgh, PA 15212 (United States)

    2010-07-15

    This paper describes a large-scale wireless and wired environmental sensor network test-bed and its application to occupancy detection in an open-plan office building. Detection of occupant presence has been used extensively in built environments for applications such as demand-controlled ventilation and security; however, the ability to discern the actual number of people in a room is beyond the scope of current sensing techniques. To address this problem, a complex sensor network is deployed in the Robert L. Preger Intelligent Workplace comprising a wireless ambient-sensing system, a wired carbon dioxide sensing system, and a wired indoor air quality sensing system. A wired camera network is implemented as well for establishing true occupancy levels to be used as ground truth information for deriving algorithmic relationships with the environment conditions. To our knowledge, this extensive and diverse ambient-sensing infrastructure of the ITEST setup as well as the continuous data-collection capability is unprecedented. Final results indicate that there are significant correlations between measured environmental conditions and occupancy status. An average of 73% accuracy on the occupancy number detection was achieved by Hidden Markov Models during testing periods. This paper serves as an exploration to the research of ITEST for occupancy detection in offices. In addition, its utility extends to a wide variety of other building technology research areas such as human-centered environmental control, security, energy efficient and sustainable green buildings. (author)

  1. Simulation to Flight Test for a UAV Controls Testbed

    Science.gov (United States)

    Motter, Mark A.; Logan, Michael J.; French, Michael L.; Guerreiro, Nelson M.

    2006-01-01

    The NASA Flying Controls Testbed (FLiC) is a relatively small and inexpensive unmanned aerial vehicle developed specifically to test highly experimental flight control approaches. The most recent version of the FLiC is configured with 16 independent aileron segments, supports the implementation of C-coded experimental controllers, and is capable of fully autonomous flight from takeoff roll to landing, including flight test maneuvers. The test vehicle is basically a modified Army target drone, AN/FQM-117B, developed as part of a collaboration between the Aviation Applied Technology Directorate (AATD) at Fort Eustis, Virginia and NASA Langley Research Center. Several vehicles have been constructed and collectively have flown over 600 successful test flights, including a fully autonomous demonstration at the Association of Unmanned Vehicle Systems International (AUVSI) UAV Demo 2005. Simulations based on wind tunnel data are being used to further develop advanced controllers for implementation and flight test.

  2. High Efficiency Traveling-Wave Tube Power Amplifier for Ka-Band Software Defined Radio on International Space Station-A Platform for Communications Technology Development

    Science.gov (United States)

    Simons, Rainee N.; Force, Dale A.; Kacpura, Thomas J.

    2013-01-01

    The design, fabrication and RF performance of the output traveling-wave tube amplifier (TWTA) for a space based Ka-band software defined radio (SDR) is presented. The TWTA, the SDR and the supporting avionics are integrated to forms a testbed, which is currently located on an exterior truss of the International Space Station (ISS). The SDR in the testbed communicates at Ka-band frequencies through a high-gain antenna directed to NASA s Tracking and Data Relay Satellite System (TDRSS), which communicates to the ground station located at White Sands Complex. The application of the testbed is for demonstrating new waveforms and software designed to enhance data delivery from scientific spacecraft and, the waveforms and software can be upgraded and reconfigured from the ground. The construction and the salient features of the Ka-band SDR are discussed. The testbed is currently undergoing on-orbit checkout and commissioning and is expected to operate for 3 to 5 years in space.

  3. Visible nulling coronagraph testbed results

    Science.gov (United States)

    Lyon, Richard G.; Clampin, Mark; Woodruff, Robert A.; Vasudevan, Gopal; Thompson, Patrick; Petrone, Peter; Madison, Timothy; Rizzo, Maxime; Melnick, Gary; Tolls, Volker

    2009-08-01

    We report on our recent laboratory results with the NASA/Goddard Space Flight Center (GSFC) Visible Nulling Coronagraph (VNC) testbed. We have experimentally achieved focal plane contrasts of 1 x 108 and approaching 109 at inner working angles of 2 * wavelength/D and 4 * wavelength/D respectively where D is the aperture diameter. The result was obtained using a broadband source with a narrowband spectral filter of width 10 nm centered on 630 nm. To date this is the deepest nulling result with a visible nulling coronagraph yet obtained. Developed also is a Null Control Breadboard (NCB) to assess and quantify MEMS based segmented deformable mirror technology and develop and assess closed-loop null sensing and control algorithm performance from both the pupil and focal planes. We have demonstrated closed-loop control at 27 Hz in the laboratory environment. Efforts are underway to first bring the contrast to > 109 necessary for the direct detection and characterization of jovian (Jupiter-like) and then to > 1010 necessary for terrestrial (Earth-like) exosolar planets. Short term advancements are expected to both broaden the spectral passband from 10 nm to 100 nm and to increase both the long-term stability to > 2 hours and the extent of the null out to a ~ 10 * wavelength / D via the use of MEMS based segmented deformable mirror technology, a coherent fiber bundle, achromatic phase shifters, all in a vacuum chamber at the GSFC VNC facility. Additionally an extreme stability textbook sized compact VNC is under development.

  4. Photovoltaic Engineering Testbed: A Facility for Space Calibration and Measurement of Solar Cells on the International Space Station

    Science.gov (United States)

    Landis, Geoffrey A.; Bailey, Sheila G.; Jenkins, Phillip; Sexton, J. Andrew; Scheiman, David; Christie, Robert; Charpie, James; Gerber, Scott S.; Johnson, D. Bruce

    2001-01-01

    The Photovoltaic Engineering Testbed ("PET") is a facility to be flown on the International Space Station to perform calibration, measurement, and qualification of solar cells in the space environment and then returning the cells to Earth for laboratory use. PET will allow rapid turnaround testing of new photovoltaic technology under AM0 conditions.

  5. ACCESS, Absolute Color Calibration Experiment for Standard Stars: Integration, Test, and Ground Performance

    Science.gov (United States)

    Kaiser, Mary Elizabeth; Morris, Matthew; Aldoroty, Lauren; Kurucz, Robert; McCandliss, Stephan; Rauscher, Bernard; Kimble, Randy; Kruk, Jeffrey; Wright, Edward L.; Feldman, Paul; Riess, Adam; Gardner, Jonathon; Bohlin, Ralph; Deustua, Susana; Dixon, Van; Sahnow, David J.; Perlmutter, Saul

    2018-01-01

    Establishing improved spectrophotometric standards is important for a broad range of missions and is relevant to many astrophysical problems. Systematic errors associated with astrophysical data used to probe fundamental astrophysical questions, such as SNeIa observations used to constrain dark energy theories, now exceed the statistical errors associated with merged databases of these measurements. ACCESS, “Absolute Color Calibration Experiment for Standard Stars”, is a series of rocket-borne sub-orbital missions and ground-based experiments designed to enable improvements in the precision of the astrophysical flux scale through the transfer of absolute laboratory detector standards from the National Institute of Standards and Technology (NIST) to a network of stellar standards with a calibration accuracy of 1% and a spectral resolving power of 500 across the 0.35‑1.7μm bandpass. To achieve this goal ACCESS (1) observes HST/ Calspec stars (2) above the atmosphere to eliminate telluric spectral contaminants (e.g. OH) (3) using a single optical path and (HgCdTe) detector (4) that is calibrated to NIST laboratory standards and (5) monitored on the ground and in-flight using a on-board calibration monitor. The observations are (6) cross-checked and extended through the generation of stellar atmosphere models for the targets. The ACCESS telescope and spectrograph have been designed, fabricated, and integrated. Subsystems have been tested. Performance results for subsystems, operations testing, and the integrated spectrograph will be presented. NASA sounding rocket grant NNX17AC83G supports this work.

  6. The 2010 Nobel Prize in physics—ground-breaking experiments on graphene

    International Nuclear Information System (INIS)

    Hancock, Y

    2011-01-01

    The 2010 Nobel Prize in physics was awarded to Professors Andre Geim and Konstantin Novoselov for their ground-breaking experiments on graphene, a single atomic layer of carbon, and more generally, for their pioneering work in uncovering a new class of materials, namely two-dimensional atomic crystals. This paper gives an accessible account and review of the story of graphene; from its first description in the literature, to the realization and confirmation of its remarkable properties, through to its impressive potential for broad-reaching applications. The story of graphene is written within the context of the enormous impact that Geim and Novoselovs' work has had on this field of research, and recounts their personal pathways of discovery, which ultimately led to their award of the 2010 Nobel Prize. (topical review)

  7. The Experiences of Young Adults With Hodgkin Lymphoma Transitioning to Survivorship: A Grounded Theory Study.

    Science.gov (United States)

    Matheson, Lauren; Boulton, Mary; Lavender, Verna; Collins, Graham; Mitchell-Floyd, Tracy; Watson, Eila

    2016-09-01

    To explore the experiences of young adults with Hodgkin lymphoma during the first year following the end of initial treatment. 
. A qualitative grounded theory study.
. Interviews with patients recruited from three cancer centers in England.
. 10 Hodgkin lymphoma survivors (four men and six women aged 21-39 years) recruited as part of a larger study of 28 young adult cancer survivors.
. Semistructured interviews were conducted about two months after treatment completion, and follow-up interviews were conducted seven months later. The authors' grounded theory of positive psychosocial adjustment to cancer provided the conceptual framework.
. Positive reframing, informal peer support, acceptance, and normalization helped young adults dismantle the threats of Hodgkin lymphoma during the course of treatment. However, they described losing a sense of security following treatment completion. Greater age-specific information to enable better preparation for the future was desired regarding body image, fertility, sexual relationships, work, and socializing.
. Informal support mechanisms, like peer support and patient navigator interventions, may be useful ways to further support young adults after treatment completion.
. Positive psychosocial adjustment to cancer survivorship in young adults is facilitated by having informal peer support; being able to positively reframe, accept, and normalize their experience; and being prepared for the future.

  8. Experimental Validation of Advanced Dispersed Fringe Sensing (ADFS) Algorithm Using Advanced Wavefront Sensing and Correction Testbed (AWCT)

    Science.gov (United States)

    Wang, Xu; Shi, Fang; Sigrist, Norbert; Seo, Byoung-Joon; Tang, Hong; Bikkannavar, Siddarayappa; Basinger, Scott; Lay, Oliver

    2012-01-01

    Large aperture telescope commonly features segment mirrors and a coarse phasing step is needed to bring these individual segments into the fine phasing capture range. Dispersed Fringe Sensing (DFS) is a powerful coarse phasing technique and its alteration is currently being used for JWST.An Advanced Dispersed Fringe Sensing (ADFS) algorithm is recently developed to improve the performance and robustness of previous DFS algorithms with better accuracy and unique solution. The first part of the paper introduces the basic ideas and the essential features of the ADFS algorithm and presents the some algorithm sensitivity study results. The second part of the paper describes the full details of algorithm validation process through the advanced wavefront sensing and correction testbed (AWCT): first, the optimization of the DFS hardware of AWCT to ensure the data accuracy and reliability is illustrated. Then, a few carefully designed algorithm validation experiments are implemented, and the corresponding data analysis results are shown. Finally the fiducial calibration using Range-Gate-Metrology technique is carried out and a <10nm or <1% algorithm accuracy is demonstrated.

  9. Electrochemical stabilization of clayey ground

    Science.gov (United States)

    Rzhanitzin, B.A.; Sokoloff, V.P.

    1947-01-01

    Recently developed new methods of stabilization of weak grounds (e.g. the silicate treatment) are based on injection of chemical solutions into the ground. Such methods are applicable accordingly only to the kinds of ground that have the coefficient of filtration higher than 2 meters per 24 hours and permit penetration of the chemical solutions under pressure. This limit, however, as it is shown by our experience in construction, excludes a numerous and an important class of grounds, stabilization of which is indispensable in many instances. For example, digging of trenches and pits in clayey, silty, or sandy ground shows that all these types act like typical "floaters" (sluds? -S) in the presence of the ground water pressure. There were several instances in the canalization of the city of Moskow where the laying of trenches below the ground water level has led to extreme difficulties with clayey and silty ground. Similar examples could be cited in mining, engineering hydrology, and railroad construction. For these reasons, the development of methods of stabilizing such difficult types of ground has become an urgent problem of our day. In 1936, the author began his investigations, at the ground Stabilization Laboratory of VODGEO Institute, with direct electrical current as the means of stabilization of grounds. Experiments had shown that a large number of clayey types, following passage of direct electrical current, undergoes a transformation of its physico-chemical properties. It was established that the (apparent -S) density of the ground is substantially increased in consequence of the application of direct electrical current. The ground loses also its capacity to swell and to soften in water. Later, after a more detailed study of the physico-chemical mechanism of the electrical stabilization, it became possible to develop the method so as to make it applicable to sandy and silty as well as to clayey ground. By this time (1941, S.), the method has already been

  10. Towards Autonomous Operations of the Robonaut 2 Humanoid Robotic Testbed

    Science.gov (United States)

    Badger, Julia; Nguyen, Vienny; Mehling, Joshua; Hambuchen, Kimberly; Diftler, Myron; Luna, Ryan; Baker, William; Joyce, Charles

    2016-01-01

    The Robonaut project has been conducting research in robotics technology on board the International Space Station (ISS) since 2012. Recently, the original upper body humanoid robot was upgraded by the addition of two climbing manipulators ("legs"), more capable processors, and new sensors, as shown in Figure 1. While Robonaut 2 (R2) has been working through checkout exercises on orbit following the upgrade, technology development on the ground has continued to advance. Through the Active Reduced Gravity Offload System (ARGOS), the Robonaut team has been able to develop technologies that will enable full operation of the robotic testbed on orbit using similar robots located at the Johnson Space Center. Once these technologies have been vetted in this way, they will be implemented and tested on the R2 unit on board the ISS. The goal of this work is to create a fully-featured robotics research platform on board the ISS to increase the technology readiness level of technologies that will aid in future exploration missions. Technology development has thus far followed two main paths, autonomous climbing and efficient tool manipulation. Central to both technologies has been the incorporation of a human robotic interaction paradigm that involves the visualization of sensory and pre-planned command data with models of the robot and its environment. Figure 2 shows screenshots of these interactive tools, built in rviz, that are used to develop and implement these technologies on R2. Robonaut 2 is designed to move along the handrails and seat track around the US lab inside the ISS. This is difficult for many reasons, namely the environment is cluttered and constrained, the robot has many degrees of freedom (DOF) it can utilize for climbing, and remote commanding for precision tasks such as grasping handrails is time-consuming and difficult. Because of this, it is important to develop the technologies needed to allow the robot to reach operator-specified positions as

  11. The experience of women in male-dominated occupations: A constructivist grounded theory inquiry

    Directory of Open Access Journals (Sweden)

    Phiona Martin

    2013-06-01

    Full Text Available Orientation: Women in male-dominated occupations face unique challenges and use distinct coping strategies affecting their motivation and retention in these occupations. Research purpose: The purpose was to explore the experiences of women working in maledominated occupations to clarify the challenges they face and identify coping strategies that enable them to continue on their career paths. Motivation for the study: Many women who choose male-dominated careers soon change in favour of more female-dominated or gender-balanced career paths. An understanding of women’s experiences may facilitate strategies geared towards their motivation and retention in male-dominated occupations. Research design, approach and method: The authors conducted this exploratory qualitative study from a constructivist grounded theory perspective. They used a purposive sample of five women and conducted in-depth unstructured interviews. They analysed data using a constructivist grounded theory methodology. Main findings: The authors found that formal and covert organisational practices, which upheld gender discrimination and bias, were the main challenges that women face. These practices included the inadequate accommodation of women’s unique physical, identity and work-life balance needs. Elements of women’s resilience included the use of femininity, adopting male characteristics, mentorship and intrinsic motivational factors. Practical/managerial implications: The findings may guide organisations to develop and implement policies, strategies and initiatives geared towards attracting, integrating, retaining, supporting and motivating women who are, or wish to be, employed in historically maledominated occupations. Contribution/value-add: This study contributes to an evolving body of knowledge aimed at understanding how to integrate and retain women in male-dominated occupations better.

  12. Emergency Nursing Experiences in Assisting People With Suicidal Behavior: A Grounded Theory Study.

    Science.gov (United States)

    Vedana, Kelly Graziani Giacchero; Magrini, Daniel Fernando; Miasso, Adriana Inocenti; Zanetti, Ana Carolina Guidorizzi; de Souza, Jacqueline; Borges, Tatiana Longo

    2017-08-01

    To understand emergency nursing experiences in assisting people with suicidal behavior. Grounded theory study with symbolic interactionism conducted in 2015 to 2016 in Brazil with 19 nurses. Assistance for people with suicidal behavior is critical, challenging, evokes different feelings and requires knowledge, skills and emotional control. Nurses did not feel prepared or supported, and identified recurrent gaps and problems. Nurses occupied a limited role, restricted to attending to physical needs. They predominantly manifested opposition, judgments and incomprehension about patients. This study presents key elements to be addressed in interventions and investigations regarding nursing support, training and supervision. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Navigating cancer using online communities: a grounded theory of survivor and family experiences.

    Science.gov (United States)

    Harkin, Lydia Jo; Beaver, Kinta; Dey, Paola; Choong, Kartina

    2017-12-01

    People affected by cancer often have unmet emotional and social support needs. Online cancer communities are a convenient channel for connecting cancer survivors, allowing them to support one another. However, it is unclear whether online community use makes a meaningful contribution to cancer survivorship, as little previous research has examined the experience of using contemporary cancer communities. We aimed to explore the experiences of visitors to online cancer communities. Twenty-three in-depth interviews were conducted with online cancer community visitors, including cancer survivors (n = 18), family members (n = 2), and individuals who were both a survivor and family member (n = 3). Interviews were analysed using a grounded theory approach. A theory developed explaining how individuals 'navigated' the experience of cancer using online cancer communities. Online advice and information led participants on a 'journey to become informed'. Online friendships normalised survivorship and cast participants on a 'journey to recreate identity'. Participants navigated a 'journey through different worlds' as they discovered relevant and hidden communities. This theory highlights virtual paths people affected by cancer can take to self-manage their experience of the disease. Online community experiences can be improved by promoting online evaluation skills and signposting visitors to bereavement support. Cancer survivors can benefit through both lurking and posting in online communities. However, individuals risk becoming distressed when they befriend individuals who may soon die. Additionally, people affected by rarer cancers can struggle to find shared experiences online and may need to look elsewhere for support.

  14. Using Grid for the BABAR Experiment

    International Nuclear Information System (INIS)

    Bozzi, C.

    2005-01-01

    The BaBar experiment has been taking data since 1999. In 2001 the computing group started to evaluate the possibility to evolve toward a distributed computing model in a grid environment. We built a prototype system, based on the European Data Grid (EDG), to submit full-scale analysis and Monte Carlo simulation jobs. Computing elements, storage elements, and worker nodes have been installed at SLAC and at various European sites. A BaBar virtual organization (VO) and a test replica catalog (RC) are maintained in Manchester, U.K., and the experiment is using three EDG testbed resource brokers in the U.K. and in Italy. First analysis tests were performed under the assumption that a standard BaBar software release was available at the grid target sites, using RC to register information about the executable and the produced n-tuples. Hundreds of analysis jobs accessing either Objectivity or Root data files ran on the grid. We tested the Monte Carlo production using a farm of the INFN-grid testbed customized to install an Objectivity database and run BaBar simulation software. First simulation production tests were performed using standard Job Description Language commands and the output files were written on the closest storage element. A package that can be officially distributed to grid sites not specifically customized for BaBar has been prepared. We are studying the possibility to add a user friendly interface to access grid services for BaBar

  15. Learning Experiences and Practices of Elementary Teacher Candidates on the Use of Emerging Technology: A Grounded Theory Approach

    Science.gov (United States)

    Bahng, EunJin; Lee, Mimi

    2017-01-01

    The purpose of this study is to understand the phenomenon of the "professional journey" of elementary teacher candidates (ETC) both as learners and as teachers by exploring their learning experiences and practices regarding the virtual reality (VR) platform called Second Life (SL). Using the grounded theory approach, we designed an…

  16. Nurses experience of using scientific knowledge in clinical practice: a grounded theory study.

    Science.gov (United States)

    Renolen, Åste; Hjälmhult, Esther

    2015-12-01

    Guidelines recommend the use of evidence-based practice in nursing. Nurses are expected to give patients care and treatment based on the best knowledge available. They may have knowledge and positive attitudes, but this does not mean that they are basing their work on evidence-based practice. Knowledge is still lacking about what is needed to successfully implement evidence-based practice. The aim of this study was to gain more knowledge about what nurses perceive as the most important challenge in implementing evidence-based practice and to explain how they act to face and overcome this challenge. We used classical grounded theory methodology and collected data through four focus groups and one individual interview in different geographical locations in one large hospital trust in Norway. Fourteen registered clinical practice nurses participated. We analysed the data in accordance with grounded theory, using the constant comparative method. Contextual balancing of knowledge emerged as the core category and explains how the nurses dealt with their main concern, how to determine what types of knowledge they could trust. The nurses' main strategies were an inquiring approach, examining knowledge and maintaining control while taking care of patients. They combined their own experienced-based knowledge and the guidelines of evidence-based practice with a sense of control in the actual situation. The grounded theory contextual balancing of knowledge may help us to understand how nurses detect what types of knowledge they can trust in clinical practice. The nurses needed to rely on what they did, and they seemed to rely on their own experience rather than on research. © 2015 Nordic College of Caring Science.

  17. On LHCb muon MWPC grounding

    CERN Document Server

    Kashchuk, A

    2006-01-01

    My goal is to study how a big MWPC system, in particular the LHCb muon system, can be protected against unstable operation and multiple spurious hits, produced by incorrect or imperfect grounding in the severe EM environment of the LHCb experiment. A mechanism of penetration of parasitic current from the ground loop to the input of the front-end amplifier is discussed. A new model of the detector cell as the electrical bridge is considered. As shown, unbalance of the bridge makes detector to be sensitive to the noise in ground loop. Resonances in ground loop are specified. Tests of multiple-point and single-point grounding conceptions made on mock-up are presented.

  18. FEBEX bentonite colloid stability in ground water

    Energy Technology Data Exchange (ETDEWEB)

    Seher, H.; Schaefer, T.; Geckeis, H. [Inst. fuer Nukleare Entsorgung (INE), Forschungszentrum Karlsruhe, 76021 Karlsruhe (Germany)]. e-mail: holger.seher@ine.fzk .de; Fanghaenel, T. [Ruprecht-Karls-Univ. Heidelberg, Physikalisch-Chemisches In st., D-69120 Heidelberg (Germany)

    2007-06-15

    Coagulation experiments are accomplished to identify the geochemical conditions for the stability of Febex bentonite colloids in granite ground water. The experiments are carried out by varying pH, ionic strength and type of electrolyte. The dynamic light scattering technique (photon correlation spectroscopy) is used to measure the size evolution of the colloids with time. Agglomeration rates are higher in MgCl{sub 2} and CaCl{sub 2} than in NaCl solution. Relative agglomeration rates follow approximately the Schulze-Hardy rule. Increasing agglomeration rates at pH>8 are observed in experiments with MgCl{sub 2} and CaCl{sub 2} which are, however, caused by coprecipitation phenomena. Bentonite colloid stability fields derived from the colloid agglomeration experiments predict low colloid stabilization in granite ground water taken from Aespoe, Sweden, and relatively high colloid stability in Grimsel ground water (Switzerland)

  19. Use of COTS in the Multimission Advanced Ground Intelligent Control (MAGIC) program

    Energy Technology Data Exchange (ETDEWEB)

    Crowley, N.L.

    1997-11-01

    This tutorial will discuss the experiences of the Space System Technologies Division of the USAF Phillips Laboratory (PL/VTS) in developing a COTS-based satellite control system. The system`s primary use is a testbed for new technologies that are intended for future integration into the operational satellite control system. As such, the control system architecture must be extremely open and flexible so we can integrate new components and functions easily and also provide our system to contractors for their component work. The system is based on commercial hardware, is based on Windows NT, and makes the maximum use of COTS components and industry standards.

  20. On-ground casualty risk reduction by structural design for demise

    Science.gov (United States)

    Lemmens, Stijn; Funke, Quirin; Krag, Holger

    2015-06-01

    In recent years, awareness concerning the on-ground risk posed by un-controlled re-entering space systems has increased. On average over the past decade, an object with mass above 800 kg re-enters every week from which only a few, e.g. ESA's GOCE in 2013 and NASA's UARS in 2011, appeared prominent in international media. Space agencies and nations have discussed requirements to limit the on-ground risk for future missions. To meet the requirements, the amount of debris falling back on Earth has to be limited in number, mass and size. Design for demise (D4D) refers to all measures taken in the design of a space object to increase the potential for demise of the object and its components during re-entry. SCARAB (Spacecraft Atmospheric Re-entry and Break-Up) is ESA's high-fidelity tool which analyses the thermal and structural effects of atmospheric re-entry on spacecraft with a finite-element approach. For this study, a model of a representative satellite is developed in SCARAB to serve as test-bed for D4D analyses on a structural level. The model is used as starting point for different D4D approaches based on increasing the exposure of the satellite components to the aero-thermal environment, as a way to speed up the demise. Statistical bootstrapping is applied to the resulting on-ground fragment lists in order to compare the different re-entry scenarios and to determine the uncertainties of the results. Moreover, the bootstrap results can be used to analyse the casualty risk estimator from a theoretical point of view. The risk reductions for the analysed D4D techniques are presented with respect to the reference scenario for the modelled representative satellite.

  1. Figure-Ground Processing: A Reassessment of Gelb and Granit.

    Science.gov (United States)

    Nelson, Rolf; Hebda, Nicholas

    2018-03-01

    In 1923, Adhemar Gelb and Ragnar Granit, two prominent researchers in early Gestalt perceptual theory, reported a lower threshold for detection of a target (a small colored dot) on the ground region of an image than on an adjacent figural region. Although their results had a wide influence on the understanding of figure-ground perception, they are at odds with more recent investigations in which figural regions appear to have a processing advantage over ground regions. The two present studies replicated Gelb and Granit's experiment using a similar figure-ground stimulus albeit with a two-alternative forced choice procedure rather than their original method of adjustment. Experiment 1 found that, contrary to Gelb and Granit's findings, a detection advantage was found for the figural over the ground region. Experiment 2 indicated that explicit contours might have played a role in detection.

  2. CanOpen on RASTA: The Integration of the CanOpen IP Core in the Avionics Testbed

    Science.gov (United States)

    Furano, Gianluca; Guettache, Farid; Magistrati, Giorgio; Tiotto, Gabriele; Ortega, Carlos Urbina; Valverde, Alberto

    2013-08-01

    This paper presents the work done within the ESA Estec Data Systems Division, targeting the integration of the CanOpen IP Core with the existing Reference Architecture Test-bed for Avionics (RASTA). RASTA is the reference testbed system of the ESA Avionics Lab, designed to integrate the main elements of a typical Data Handling system. It aims at simulating a scenario where a Mission Control Center communicates with on-board computers and systems through a TM/TC link, thus providing the data management through qualified processors and interfaces such as Leon2 core processors, CAN bus controllers, MIL-STD-1553 and SpaceWire. This activity aims at the extension of the RASTA with two boards equipped with HurriCANe controller, acting as CANOpen slaves. CANOpen software modules have been ported on the RASTA system I/O boards equipped with Gaisler GR-CAN controller and acts as master communicating with the CCIPC boards. CanOpen serves as upper application layer for based on CAN defined within the CAN-in-Automation standard and can be regarded as the definitive standard for the implementation of CAN-based systems solutions. The development and integration of CCIPC performed by SITAEL S.p.A., is the first application that aims to bring the CANOpen standard for space applications. The definition of CANOpen within the European Cooperation for Space Standardization (ECSS) is under development.

  3. PAPI based federation as a test-bed for a common security infrastructure in EFDA sites

    International Nuclear Information System (INIS)

    Castro, R.; Vega, J.; Portas, A.; Lopez, D.R.; Balme, S.; Theis, J.M.; Lebourg, P.; Fernandes, H.; Neto, A.; Duarte, A.; Oliveira, F.; Reis, F.; Purahoo, K.; Thomsen, K.; Schiller, W.; Kadlecsik, J.

    2008-01-01

    Federated authentication and authorization systems provide several advantages to collaborative environments, for example, easy authentication integration, simpler user management, easier security policy implementation and quicker implementation of access control elements for new type of resources. A federation integrates different aspects that have to be coordinated by all the organizations involved. The most relevant are: definition of common schemas and attributes, definition of common policies and procedures, management of keys and certificates, management of common repositories and implementation of a home location service. A federation enabling collaboration of European sites has been put into operation. Four laboratories have been integrated and two more organizations (EFDA and KFKI/HAS) are finishing their integration. The federation infrastructure is based on Point of Access to Providers of Information (PAPI), a distributed authentication and authorization system. PAPI technology gives some important features, such as, single sign on for accessing to different resources, mobility for users, and compatibility with open and standard technologies: Java, JNLP protocol, XML-RPC and web technologies among others. In this article, the test-bed of EFDA federation is presented. Some examples of resources, securely shared inside the federation, are shown. Specific issues and experience gained in deploying federated collaboration systems will be addressed as well

  4. PAPI based federation as a test-bed for a common security infrastructure in EFDA sites

    Energy Technology Data Exchange (ETDEWEB)

    Castro, R. [Asociacion EURATOM/CIEMAT para Fusion, Madrid (Spain)], E-mail: rodrigo.castro@ciemat.es; Vega, J.; Portas, A. [Asociacion EURATOM/CIEMAT para Fusion, Madrid (Spain); Lopez, D.R. [Departamento RedIRIS, Entidad publica empresarial Red.es, Madrid (Spain); Balme, S.; Theis, J.M.; Lebourg, P. [Association EURATOM-CEA, CEA/DSM/Departement de Recherches sur la Fusion Controlee DRFC, CEA-Cadarache (France); Fernandes, H.; Neto, A.; Duarte, A.; Oliveira, F.; Reis, F. [Centro de Fusao Nuclear, Associacao EURATOM/IST, Lisboa (Portugal); Purahoo, K. [EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Thomsen, K.; Schiller, W. [EFDA Close Support Unit Garching, Max Planck Institut fuer Plasmaphysik, Boltzmannstr. 2, D-85748 Garching (Germany); Kadlecsik, J. [KFKI R.I. for Particle and Nuclear Physics of the Hungarian Academy of Sciences, and the Association EURATOM/HAS, Budapest (Hungary)

    2008-04-15

    Federated authentication and authorization systems provide several advantages to collaborative environments, for example, easy authentication integration, simpler user management, easier security policy implementation and quicker implementation of access control elements for new type of resources. A federation integrates different aspects that have to be coordinated by all the organizations involved. The most relevant are: definition of common schemas and attributes, definition of common policies and procedures, management of keys and certificates, management of common repositories and implementation of a home location service. A federation enabling collaboration of European sites has been put into operation. Four laboratories have been integrated and two more organizations (EFDA and KFKI/HAS) are finishing their integration. The federation infrastructure is based on Point of Access to Providers of Information (PAPI), a distributed authentication and authorization system. PAPI technology gives some important features, such as, single sign on for accessing to different resources, mobility for users, and compatibility with open and standard technologies: Java, JNLP protocol, XML-RPC and web technologies among others. In this article, the test-bed of EFDA federation is presented. Some examples of resources, securely shared inside the federation, are shown. Specific issues and experience gained in deploying federated collaboration systems will be addressed as well.

  5. Ground-based acoustic parametric generator impact on the atmosphere and ionosphere in an active experiment

    Directory of Open Access Journals (Sweden)

    Y. G. Rapoport

    2017-01-01

    Full Text Available We develop theoretical basics of active experiments with two beams of acoustic waves, radiated by a ground-based sound generator. These beams are transformed into atmospheric acoustic gravity waves (AGWs, which have parameters that enable them to penetrate to the altitudes of the ionospheric E and F regions where they influence the electron concentration of the ionosphere. Acoustic waves are generated by the ground-based parametric sound generator (PSG at the two close frequencies. The main idea of the experiment is to design the output parameters of the PSG to build a cascade scheme of nonlinear wave frequency downshift transformations to provide the necessary conditions for their vertical propagation and to enable penetration to ionospheric altitudes. The PSG generates sound waves (SWs with frequencies f1 = 600 and f2 = 625 Hz and large amplitudes (100–420 m s−1. Each of these waves is modulated with the frequency of 0.016 Hz. The novelty of the proposed analytical–numerical model is due to simultaneous accounting for nonlinearity, diffraction, losses, and dispersion and inclusion of the two-stage transformation (1 of the initial acoustic waves to the acoustic wave with the difference frequency Δf = f2 − f1 in the altitude ranges 0–0.1 km, in the strongly nonlinear regime, and (2 of the acoustic wave with the difference frequency to atmospheric acoustic gravity waves with the modulational frequency in the altitude ranges 0.1–20 km, which then reach the altitudes of the ionospheric E and F regions, in a practically linear regime. AGWs, nonlinearly transformed from the sound waves, launched by the two-frequency ground-based sound generator can increase the transparency of the ionosphere for the electromagnetic waves in HF (MHz and VLF (kHz ranges. The developed theoretical model can be used for interpreting an active experiment that includes the PSG impact on the atmosphere–ionosphere system

  6. Workplace Bullying in Academe: A Grounded Theory Study Exploring How Faculty Cope with the Experience of Being Bullied

    Science.gov (United States)

    Wilkin, La Vena

    2010-01-01

    This qualitative study used a grounded theory methodology to generate a theory about how targets of workplace bullying in academe may begin to heal from the aftermath of their ill-treatment. The emphasis was on understanding the experiences of university faculty members who had been targets of workplace bullying. A key factor in this study was to…

  7. Symbol Grounding Without Direct Experience: Do Words Inherit Sensorimotor Activation From Purely Linguistic Context?

    Science.gov (United States)

    Günther, Fritz; Dudschig, Carolin; Kaup, Barbara

    2018-05-01

    Theories of embodied cognition assume that concepts are grounded in non-linguistic, sensorimotor experience. In support of this assumption, previous studies have shown that upwards response movements are faster than downwards movements after participants have been presented with words whose referents are typically located in the upper vertical space (and vice versa for downwards responses). This is taken as evidence that processing these words reactivates sensorimotor experiential traces. This congruency effect was also found for novel words, after participants learned these words as labels for novel objects that they encountered either in their upper or lower visual field. While this indicates that direct experience with a word's referent is sufficient to evoke said congruency effects, the present study investigates whether this direct experience is also a necessary condition. To this end, we conducted five experiments in which participants learned novel words from purely linguistic input: Novel words were presented in pairs with real up- or down-words (Experiment 1); they were presented in natural sentences where they replaced these real words (Experiment 2); they were presented as new labels for these real words (Experiment 3); and they were presented as labels for novel combined concepts based on these real words (Experiment 4 and 5). In all five experiments, we did not find any congruency effects elicited by the novel words; however, participants were always able to make correct explicit judgements about the vertical dimension associated to the novel words. These results suggest that direct experience is necessary for reactivating experiential traces, but this reactivation is not a necessary condition for understanding (in the sense of storing and accessing) the corresponding aspects of word meaning. Copyright © 2017 Cognitive Science Society, Inc.

  8. A robot hand testbed designed for enhancing embodiment and functional neurorehabilitation of body schema in subjects with upper limb impairment or loss.

    Science.gov (United States)

    Hellman, Randall B; Chang, Eric; Tanner, Justin; Helms Tillery, Stephen I; Santos, Veronica J

    2015-01-01

    Many upper limb amputees experience an incessant, post-amputation "phantom limb pain" and report that their missing limbs feel paralyzed in an uncomfortable posture. One hypothesis is that efferent commands no longer generate expected afferent signals, such as proprioceptive feedback from changes in limb configuration, and that the mismatch of motor commands and visual feedback is interpreted as pain. Non-invasive therapeutic techniques for treating phantom limb pain, such as mirror visual feedback (MVF), rely on visualizations of postural changes. Advances in neural interfaces for artificial sensory feedback now make it possible to combine MVF with a high-tech "rubber hand" illusion, in which subjects develop a sense of embodiment with a fake hand when subjected to congruent visual and somatosensory feedback. We discuss clinical benefits that could arise from the confluence of known concepts such as MVF and the rubber hand illusion, and new technologies such as neural interfaces for sensory feedback and highly sensorized robot hand testbeds, such as the "BairClaw" presented here. Our multi-articulating, anthropomorphic robot testbed can be used to study proprioceptive and tactile sensory stimuli during physical finger-object interactions. Conceived for artificial grasp, manipulation, and haptic exploration, the BairClaw could also be used for future studies on the neurorehabilitation of somatosensory disorders due to upper limb impairment or loss. A remote actuation system enables the modular control of tendon-driven hands. The artificial proprioception system enables direct measurement of joint angles and tendon tensions while temperature, vibration, and skin deformation are provided by a multimodal tactile sensor. The provision of multimodal sensory feedback that is spatiotemporally consistent with commanded actions could lead to benefits such as reduced phantom limb pain, and increased prosthesis use due to improved functionality and reduced cognitive burden.

  9. A robot hand testbed designed for enhancing embodiment and functional neurorehabilitation of body schema in subjects with upper limb impairment or loss

    Directory of Open Access Journals (Sweden)

    Randall B. Hellman

    2015-02-01

    Full Text Available Many upper limb amputees experience an incessant, post-amputation phantom limb pain and report that their missing limbs feel paralyzed in an uncomfortable posture. One hypothesis is that efferent commands no longer generate expected afferent signals, such as proprioceptive feedback from changes in limb configuration, and that the mismatch of motor commands and visual feedback is interpreted as pain. Non-invasive therapeutic techniques for treating phantom limb pain, such as mirror visual feedback (MVF, rely on visualizations of postural changes. Advances in neural interfaces for artificial sensory feedback now make it possible to combine MVF with a high-tech rubber hand illusion, in which subjects develop a sense of embodiment with a fake hand when subjected to congruent visual and somatosensory feedback. We discuss clinical benefits that could arise from the confluence of known concepts such as MVF and the rubber hand illusion, and new technologies such as neural interfaces for sensory feedback and highly sensorized robot hand testbeds, such as the BairClaw presented here. Our multi-articulating, anthropomorphic robot testbed can be used to study proprioceptive and tactile sensory stimuli during physical finger-object interactions. Conceived for artificial grasp, manipulation, and haptic exploration, the BairClaw could also be used for future studies on the neurorehabilitation of somatosensory disorders due to upper limb impairment or loss. A remote actuation system enables the modular control of tendon-driven hands. The artificial proprioception system enables direct measurement of joint angles and tendon tensions while temperature, vibration, and skin deformation are provided by a multimodal tactile sensor. The provision of multimodal sensory feedback that is spatiotemporally consistent with commanded actions could lead to benefits such as reduced phantom limb pain, and increased prosthesis use due to improved functionality and reduced

  10. Competence in providing mental health care: a grounded theory analysis of nurses' experiences.

    Science.gov (United States)

    Sharrock, Julie; Happell, Brenda

    In view of the evidence that general nurses have difficulty in caring for patients experiencing mental health problems, the aim of this study was to explore and describe the subjective experience of nurses in providing care for this client group. A grounded theory approach was used. The data were collected via semi-structured individual interviews and analysed using the constant comparative method. The study was conducted with nurses from general health care settings that provide medical and surgical care and treatment. Four nurses who were completing their second year post graduation participated in the study. The experiences of providing care for people experiencing a mental illness as described by participants. The findings indicated the nurses were striving for competence in the provision of mental health care. They acknowledged the mental health needs of patients and their right to quality care. This study supports the notion that general nurses lack confidence when caring for patients with mental health problems in medical and surgical settings. It also highlights a discrepancy between the holistic framework encouraged at undergraduate level and what is experienced in practice.

  11. Running the figure to the ground: figure-ground segmentation during visual search.

    Science.gov (United States)

    Ralph, Brandon C W; Seli, Paul; Cheng, Vivian O Y; Solman, Grayden J F; Smilek, Daniel

    2014-04-01

    We examined how figure-ground segmentation occurs across multiple regions of a visual array during a visual search task. Stimuli consisted of arrays of black-and-white figure-ground images in which roughly half of each image depicted a meaningful object, whereas the other half constituted a less meaningful shape. The colours of the meaningful regions of the targets and distractors were either the same (congruent) or different (incongruent). We found that incongruent targets took longer to locate than congruent targets (Experiments 1, 2, and 3) and that this segmentation-congruency effect decreased when the number of search items was reduced (Experiment 2). Furthermore, an analysis of eye movements revealed that participants spent more time scrutinising the target before confirming its identity on incongruent trials than on congruent trials (Experiment 3). These findings suggest that the distractor context influences target segmentation and detection during visual search. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Overview of the Transport Rotorcraft Airframe Crash Testbed (TRACT) Full Scale Crash Tests

    Science.gov (United States)

    Annett, Martin; Littell, Justin

    2015-01-01

    The Transport Rotorcraft Airframe Crash Testbed (TRACT) full-scale tests were performed at NASA Langley Research Center's Landing and Impact Research Facility in 2013 and 2014. Two CH-46E airframes were impacted at 33-ft/s forward and 25-ft/s vertical combined velocities onto soft soil, which represents a severe, but potentially survivable impact scenario. TRACT 1 provided a baseline set of responses, while TRACT 2 included retrofits with composite subfloors and other crash system improvements based on TRACT 1. For TRACT 2, a total of 18 unique experiments were conducted to evaluate Anthropomorphic Test Devices (ATD) responses, seat and restraint performance, cargo restraint effectiveness, patient litter behavior, and activation of emergency locator transmitters and crash sensors. Combinations of Hybrid II, Hybrid III, and ES-2 ATDs were placed in forward and side facing seats and occupant results were compared against injury criteria. The structural response of the airframe was assessed based on accelerometers located throughout the airframe and using three-dimensional photogrammetric techniques. Analysis of the photogrammetric data indicated regions of maximum deflection and permanent deformation. The response of TRACT 2 was noticeably different in the horizontal direction due to changes in the cabin configuration and soil surface, with higher acceleration and damage occurring in the cabin. Loads from ATDs in energy absorbing seats and restraints were within injury limits. Severe injury was likely for ATDs in forward facing passenger seats.

  13. Communication, concepts and grounding.

    Science.gov (United States)

    van der Velde, Frank

    2015-02-01

    This article discusses the relation between communication and conceptual grounding. In the brain, neurons, circuits and brain areas are involved in the representation of a concept, grounding it in perception and action. In terms of grounding we can distinguish between communication within the brain and communication between humans or between humans and machines. In the first form of communication, a concept is activated by sensory input. Due to grounding, the information provided by this communication is not just determined by the sensory input but also by the outgoing connection structure of the conceptual representation, which is based on previous experiences and actions. The second form of communication, that between humans or between humans and machines, is influenced by the first form. In particular, a more successful interpersonal communication might require forms of situated cognition and interaction in which the entire representations of grounded concepts are involved. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. LWIR passive perception system for stealthy unmanned ground vehicle night operations

    Science.gov (United States)

    Lee, Daren; Rankin, Arturo; Huertas, Andres; Nash, Jeremy; Ahuja, Gaurav; Matthies, Larry

    2016-05-01

    Resupplying forward-deployed units in rugged terrain in the presence of hostile forces creates a high threat to manned air and ground vehicles. An autonomous unmanned ground vehicle (UGV) capable of navigating stealthily at night in off-road and on-road terrain could significantly increase the safety and success rate of such resupply missions for warfighters. Passive night-time perception of terrain and obstacle features is a vital requirement for such missions. As part of the ONR 30 Autonomy Team, the Jet Propulsion Laboratory developed a passive, low-cost night-time perception system under the ONR Expeditionary Maneuver Warfare and Combating Terrorism Applied Research program. Using a stereo pair of forward looking LWIR uncooled microbolometer cameras, the perception system generates disparity maps using a local window-based stereo correlator to achieve real-time performance while maintaining low power consumption. To overcome the lower signal-to-noise ratio and spatial resolution of LWIR thermal imaging technologies, a series of pre-filters were applied to the input images to increase the image contrast and stereo correlator enhancements were applied to increase the disparity density. To overcome false positives generated by mixed pixels, noisy disparities from repeated textures, and uncertainty in far range measurements, a series of consistency, multi-resolution, and temporal based post-filters were employed to improve the fidelity of the output range measurements. The stereo processing leverages multi-core processors and runs under the Robot Operating System (ROS). The night-time passive perception system was tested and evaluated on fully autonomous testbed ground vehicles at SPAWAR Systems Center Pacific (SSC Pacific) and Marine Corps Base Camp Pendleton, California. This paper describes the challenges, techniques, and experimental results of developing a passive, low-cost perception system for night-time autonomous navigation.

  15. Rigour and grounded theory.

    Science.gov (United States)

    Cooney, Adeline

    2011-01-01

    This paper explores ways to enhance and demonstrate rigour in a grounded theory study. Grounded theory is sometimes criticised for a lack of rigour. Beck (1993) identified credibility, auditability and fittingness as the main standards of rigour for qualitative research methods. These criteria were evaluated for applicability to a Straussian grounded theory study and expanded or refocused where necessary. The author uses a Straussian grounded theory study (Cooney, In press) to examine how the revised criteria can be applied when conducting a grounded theory study. Strauss and Corbin (1998b) criteria for judging the adequacy of a grounded theory were examined in the context of the wider literature examining rigour in qualitative research studies in general and grounded theory studies in particular. A literature search for 'rigour' and 'grounded theory' was carried out to support this analysis. Criteria are suggested for enhancing and demonstrating the rigour of a Straussian grounded theory study. These include: cross-checking emerging concepts against participants' meanings, asking experts if the theory 'fit' their experiences, and recording detailed memos outlining all analytical and sampling decisions. IMPLICATIONS FOR RESEARCH PRACTICE: The criteria identified have been expressed as questions to enable novice researchers to audit the extent to which they are demonstrating rigour when writing up their studies. However, it should not be forgotten that rigour is built into the grounded theory method through the inductive-deductive cycle of theory generation. Care in applying the grounded theory methodology correctly is the single most important factor in ensuring rigour.

  16. French network and acquired experience on record strong ground motion

    International Nuclear Information System (INIS)

    Ferrieux, H.; Mohammadioun, G.

    1988-03-01

    The network intended to record strong ground motion in continental France is composed for the most part of instrument packages incorporated into nuclear installations, which are supplemented by a certain number of accelerometers placed in the most highly seismic areas. In a country where the level of seismicity is relatively modest, such a network is not conductive to the acquisition of new data, which, instead, is obtained through spot studies of limited duration using more sensitive instruments or through the recording of strong ground motion in neighbouring countries [fr

  17. MODELING CIRCUMSTELLAR DISKS OF B-TYPE STARS WITH OBSERVATIONS FROM THE PALOMAR TESTBED INTERFEROMETER

    International Nuclear Information System (INIS)

    Grzenia, B. J.; Tycner, C.; Jones, C. E.; Sigut, T. A. A.; Rinehart, S. A.; Van Belle, G. T.

    2013-01-01

    Geometrical (uniform disk) and numerical models were calculated for a set of B-emission (Be) stars observed with the Palomar Testbed Interferometer (PTI). Physical extents have been estimated for the disks of a total of 15 stars via uniform disk models. Our numerical non-LTE models used parameters for the B0, B2, B5, and B8 spectral classes and following the framework laid by previous studies, we have compared them to infrared K-band interferometric observations taken at PTI. This is the first time such an extensive set of Be stars observed with long-baseline interferometry has been analyzed with self-consistent non-LTE numerical disk models.

  18. Atmospheric Fluctuation Measurements with the Palomar Testbed Interferometer

    Science.gov (United States)

    Linfield, R. P.; Lane, B. F.; Colavita, M. M.; PTI Collaboration

    Observations of bright stars with the Palomar Testbed Interferometer, at a wavelength of 2.2 microns, have been used to measure atmospheric delay fluctuations. The delay structure function Dτ(Δ t) was calculated for 66 scans (each >= 120s in length) on seven nights in 1997 and one in 1998. For all except one scan, Dτ exhibited a clean power law shape over the time interval 50-500 msec. Over shorter time intervals, the effect of the delay line servo loop corrupts Dτ. Over longer time intervals (usually starting at > 1s), the slope of Dτ decreases, presumably due to some combination of saturation e.g. finite turbulent layer thickness) and the effect of the finite wind speed crossing time on our 110 m baseline. The mean power law slopes for the eight nights ranged from 1.16 to 1.36, substantially flatter than the value of 1.67 for three dimensional Kolmogorov turbulence. Such sub-Kolmogorov slopes will result in atmospheric seeling (θ) that improves rapidly with increasing wavelength: θ propto λ1-(2β), where β is the observed power law slope of Dτ. The atmospheric errors in astrometric measurements with an interferometer will average down more quickly than in the Kolmogorov case.

  19. Report of the Interagency Optical Network Testbeds Workshop 2, NASA Ames Research Center, September 12-14, 2005

    Science.gov (United States)

    2005-01-01

    The Optical Network Testbeds Workshop 2 (ONT2), held on September 12-14, 2005, was cosponsored by the Department of Energy Office of Science (DOE/SC) and the National Aeronautics and Space Administration (NASA), in cooperation with the Joint Engineering Team (JET) of the Federal Networking and Information Technology Research and Development (NITRD) Program's Large Scale Networking (LSN) Coordinating Group. The ONT2 workshop was a follow-on to an August 2004 Workshop on Optical Network Testbeds (ONT1). ONT1 recommended actions by the Federal agencies to assure timely development and implementation of optical networking technologies and infrastructure. Hosted by the NASA Ames Research Center in Mountain View, California, the ONT2 workshop brought together representatives of the U.S. advanced research and education (R&E) networks, regional optical networks (RONs), service providers, international networking organizations, and senior engineering and R&D managers from Federal agencies and national research laboratories. Its purpose was to develop a common vision of the optical network technologies, services, infrastructure, and organizations needed to enable widespread use of optical networks; recommend activities for transitioning the optical networking research community and its current infrastructure to leading-edge optical networks over the next three to five years; and present information enabling commercial network infrastructure providers to plan for and use leading-edge optical network services in that time frame.

  20. Evaluation of multimodal ground cues

    DEFF Research Database (Denmark)

    Nordahl, Rolf; Lecuyer, Anatole; Serafin, Stefania

    2012-01-01

    This chapter presents an array of results on the perception of ground surfaces via multiple sensory modalities,with special attention to non visual perceptual cues, notably those arising from audition and haptics, as well as interactions between them. It also reviews approaches to combining...... synthetic multimodal cues, from vision, haptics, and audition, in order to realize virtual experiences of walking on simulated ground surfaces or other features....

  1. Oceanic Platform of the Canary Islands: an ocean testbed for ocean energy converters

    Science.gov (United States)

    González, Javier; Hernández-Brito, Joaquín.; Llinás, Octavio

    2010-05-01

    The Oceanic Platform of the Canary Islands (PLOCAN) is a Governmental Consortium aimed to build and operate an off-shore infrastructure to facilitate the deep sea research and speed up the technology associated. This Consortium is overseen by the Spanish Ministry of Science and Innovation and the Canarian Agency for Research and Innovation. The infrastructure consists of an oceanic platform located in an area with depths between 50-100 meters, close to the continental slope and four kilometers off the coast of Gran Canaria, in the archipelago of the Canary Islands. The process of construction will start during the first months of 2010 and is expected to be finished in mid-year 2011. PLOCAN serves five strategic lines: an integral observatory able to explore from the deep ocean to the atmosphere, an ocean technology testbed, a base for underwater vehicles, an innovation platform and a highly specialized training centre. Ocean energy is a suitable source to contribute the limited mix-energy conformed in the archipelago of the Canary Islands with a total population around 2 million people unequally distributed in seven islands. Islands of Gran Canaria and Tenerife support the 80% of the total population with 800.000 people each. PLOCAN will contribute to develop the ocean energy sector establishing a marine testbed allowing prototypes testing at sea under a meticulous monitoring network provided by the integral observatory, generating valuable information to developers. Reducing costs throughout an integral project management is an essential objective to be reach, providing services such as transportation, customs and administrative permits. Ocean surface for testing activities is around 8 km2 with a depth going from 50 to 100 meters, 4km off the coast. Selected areas for testing have off-shore wind power conditions around 500-600 W/m2 and wave power conditions around 6 kW/m in the East coast and 10 kW/m in the North coast. Marine currents in the Canary Islands are

  2. Mid-infrared picosecond pump-dump-probe and pump-repump-probe experiments to resolve a ground-state intermediate in cyanobacterial phytochrome Cph1.

    Science.gov (United States)

    van Wilderen, Luuk J G W; Clark, Ian P; Towrie, Michael; van Thor, Jasper J

    2009-12-24

    Multipulse picosecond mid-infrared spectroscopy has been used to study photochemical reactions of the cyanobacterial phytochrome photoreceptor Cph1. Different photophysical schemes have been discussed in the literature to describe the pathways after photoexcitation, particularly, to identify reaction phases that are linked to photoisomerisation and electronic decay in the 1566-1772 cm(-1) region that probes C=C and C=O stretching modes of the tetrapyrrole chromophore. Here, multipulse spectroscopy is employed, where, compared to conventional visible pump-mid-infrared probe spectroscopy, an additional visible pulse is incorporated that interacts with populations that are evolving on the excited- and ground-state potential energy surfaces. The time delays between the pump and the dump pulse are chosen such that the dump pulse interacts with different phases in the reaction process. The pump and dump pulses are at the same wavelength, 640 nm, and are resonant with the Pr ground state as well as with the excited state and intermediates. Because the dump pulse additionally pumps the remaining, partially recovered, and partially oriented ground-state population, theory is developed for estimating the fraction of excited-state molecules. The calculations take into account the model-dependent ground-state recovery fraction, the angular dependence of the population transfer resulting from the finite bleach that occurs with linearly polarized intense femtosecond optical excitation, and the partially oriented population for the dump field. Distinct differences between the results from the experiments that use a 1 or a 14 ps dump time favor a branching evolution from S1 to an excited state or reconfigured chromophore and to a newly identified ground-state intermediate (GSI). Optical dumping at 1 ps shows the instantaneous induced absorption of a delocalized C=C stretching mode at 1608 cm(-1), where the increased cross section is associated with the electronic ground

  3. Experimental Results From a 2kW Brayton Power Conversion Unit

    Science.gov (United States)

    Hervol, David; Mason, Lee; Birchenough, Arthur

    2003-01-01

    This paper presents experimental test results from operation of a 2 kWe Brayton power conversion unit. The Brayton converter was developed for a solar dynamic power system flight experiment planned for the Mir Space Station in 1997. The flight experiment was cancelled, but the converter was tested at Glenn Research Center as part of the Solar Dynamic Ground Test Demonstration system which included a solar concentrator, heat receiver, and space radiator. In preparation for the current testing, the heat receiver was removed and replaced with an electrical resistance heater, simulating the thermal input of a steady-state nuclear source. The converter was operated over a full range of thermal input power levels and rotor speeds to generate an overall performance map. The converter unit will serve as the centerpiece of a Nuclear Electric Propulsion Testbed at Glenn. Future potential uses for the Testbed include high voltage electrical controller development, integrated electric thruster testing and advanced radiator demonstration testing to help guide high power Brayton technology development for Nuclear Electric Propulsion (NEP).

  4. CubeSub - A CubeSat Based Submersible Testbed for Space Technology

    Science.gov (United States)

    Slettebo, Christian

    2016-01-01

    This report is a Master's Thesis in Aerospace Engineering, performed at the NASA Ames Research Center. It describes the development of the CubeSub, a submersible testbed compatible with the CubeSat form factor. The CubeSub will be used to mature technology and operational procedures to be used in space exploration, and possibly also as a tool for exploration of Earthly environments. CubeSats are carried as payloads, either containing technology to be tested or experiments and sensors for scientific use. The CubeSub is designed to be built up by modules, which can be assembled in different configurations to fulfill different needs. Each module is powered individually and intermodular communication is wireless, reducing the need for wiring. The inside of the hull is flooded with ambient water to simplify the interaction between payloads and surrounding environment. The overall shape is similar to that of a conventional AUV, slender and smooth. This is to make for a low drag, reduce the risk of snagging on surrounding objects and make it possible to deploy through an ice sheet via a narrow borehole. Rapid prototyping is utilized to a large extent, with full-scale prototypes being constructed through 3D-printing and with COTS (Commercial Off-The-Shelf) components. Arduino boards are used for control and internal communication. Modules required for basic operation have been designed, manufactured and tested. Each module is described with regards to its function, design and manufacturability. By performing tests in a pool it was found that the basic concept is sound and that future improvements include better controllability, course stability and waterproofing of electrical components. Further development is needed to make the CubeSub usable for its intended purposes. The largest gains are expected to be found by developing the software and improving controllability.

  5. A study of Iranian immigrants’ experiences of accessing Canadian health care services: a grounded theory

    Directory of Open Access Journals (Sweden)

    Dastjerdi Mahdieh

    2012-09-01

    Full Text Available Abstract Background Immigration is not a new phenomenon but, rather, has deep roots in human history. Documents from every era detail individuals who left their homelands and struggled to reestablish their lives in other countries. The aim of this study was to explore and understand the experience of Iranian immigrants who accessed Canadian health care services. Research with immigrants is useful for learning about strategies that newcomers develop to access health care services. Methods The research question guiding this study was, “What are the processes by which Iranian immigrants learn to access health care services in Canada?” To answer the question, a constructivist grounded theory approach was applied. Initially, unstructured interviews were conducted with 17 participants (11 women and six men who were adults (at least 18 years old and had immigrated to Canada within the past 15 years. Eight participants took part in a second interview, and four participants took part in a third interview. Results Using a constructivist grounded theory approach, “tackling the stumbling blocks of access” emerged as the core category. The basic social process (BSP, becoming self-sufficient, was a transitional process and had five stages: becoming a stranger; feeling helpless; navigating/seeking information; employing strategies; and becoming integrated and self-sufficient. We found that “tackling the stumbling blocks of access” was the main struggle throughout this journey. Some of the immigrants were able to overcome these challenges and became proficient in accessing health care services, but others were unable to make the necessary changes and thus stayed in earlier stages/phases of transition, and sometimes returned to their country of origin. Conclusion During the course of this journey a substantive grounded theory was developed that revealed the challenges and issues confronted by this particular group of immigrants. This process explains

  6. Extrasolar Planetary Imaging Coronagraph: Visible Nulling Coronagraph Testbed Results

    Science.gov (United States)

    Lyon, Richard G.

    2008-01-01

    The Extrasolar Planetary Imaging Coronagraph (EPIC) is a proposed NASA Discovery mission to image and characterize extrasolar giant planets in orbits with semi-major axes between 2 and 10 AU. EPIC will provide insights into the physical nature of a variety of planets in other solar systems complimenting radial velocity (RV) and astrometric planet searches. It will detect and characterize the atmospheres of planets identified by radial velocity surveys, determine orbital inclinations and masses, characterize the atmospheres around A and F stars, observed the inner spatial structure and colors of inner Spitzer selected debris disks. EPIC would be launched to heliocentric Earth trailing drift-away orbit, with a 3-year mission lifetime ( 5 year goal) and will revisit planets at least three times at intervals of 9 months. The starlight suppression approach consists of a visible nulling coronagraph (VNC) that enables high order starlight suppression in broadband light. To demonstrate the VNC approach and advance it's technology readiness the NASA Goddard Space Flight Center and Lockheed-Martin have developed a laboratory VNC and have demonstrated white light nulling. We will discuss our ongoing VNC work and show the latest results from the VNC testbed,

  7. User's guide to the Reliability Estimation System Testbed (REST)

    Science.gov (United States)

    Nicol, David M.; Palumbo, Daniel L.; Rifkin, Adam

    1992-01-01

    The Reliability Estimation System Testbed is an X-window based reliability modeling tool that was created to explore the use of the Reliability Modeling Language (RML). RML was defined to support several reliability analysis techniques including modularization, graphical representation, Failure Mode Effects Simulation (FMES), and parallel processing. These techniques are most useful in modeling large systems. Using modularization, an analyst can create reliability models for individual system components. The modules can be tested separately and then combined to compute the total system reliability. Because a one-to-one relationship can be established between system components and the reliability modules, a graphical user interface may be used to describe the system model. RML was designed to permit message passing between modules. This feature enables reliability modeling based on a run time simulation of the system wide effects of a component's failure modes. The use of failure modes effects simulation enhances the analyst's ability to correctly express system behavior when using the modularization approach to reliability modeling. To alleviate the computation bottleneck often found in large reliability models, REST was designed to take advantage of parallel processing on hypercube processors.

  8. Development of small-bore, high-current-density railgun as testbed for study of plasma-materials interaction. Progress report for October 16, 2000 - May 13, 2003

    International Nuclear Information System (INIS)

    Kyekyoon, Kim-Kevin

    2003-01-01

    The present document is a final technical report summarizing the progress made during 10/16/2000 - 05/13/2003 toward the development of a small-bore railgun with transaugmentation as a testbed for investigating plasma-materials interaction

  9. Long-term agricultural experiments inform the development of climate-smart agricultural practices

    Directory of Open Access Journals (Sweden)

    Kristina Wolf

    2017-09-01

    Full Text Available California's Mediterranean agro-ecosystems are a major source of U.S. fruits and vegetables, and vulnerable to future extremes of precipitation and temperature brought on by climate change, including increased drought and flooding, and more intense and longer heat waves. To develop resilience to these threats, strategies are necessary for climate-smart management of soil and water. Long-term, large-scale, replicated ecological experiments provide unique testbeds for studying such questions. At the UC Davis Russell Ranch Sustainable Agriculture Facility (RRSAF, the 100-year Century Experiment, initiated in 1992, is investigating the effects of multiple farming practices in a farm-scale replicated study of 10 row crop cropping systems. It includes different fertility management systems: organic, conventional and hybrid (conventional plus winter cover crop systems; different crops: wheat, tomatoes, corn, alfalfa, cover crops and grasslands; and different irrigation systems: rainfed, flood irrigated and drip irrigated. We briefly describe and report on a selection of long-term experiments conducted at RRSAF investigating soil management and irrigation practices, which are an important focus for developing climate-smart strategies in Mediterranean systems. For example, long-term monitoring of soil carbon content revealed that most crop systems have experienced a small increase in soil carbon since 1993, and increases in organically managed plots were substantially higher. As RRSAF continues to build upon this rich dataset from one of a very few long-term row crop experiments in Mediterranean ecosystems, it provides a testbed for identifying climate-smart solutions for these agronomically important ecosystems.

  10. A Rural Next Generation Network (R-NGN and Its Testbed

    Directory of Open Access Journals (Sweden)

    Armein Z. R. Langi

    2007-05-01

    Full Text Available Rural Next Generation Networks (R-NGN technology allows Internet protocol (IP based systems to be used in rural areas. This paper reports a testbed of R-NGN that uses low cost Ethernet radio links, combined with media gateways and a softswitch. The network consists of point-to-point IP Ethernet 2.4 GHz wireless link, IP switches and gateways in each community, standard copper wires and telephone sets for users. It uses low power consumption, and suitable for low density users. This combination allows low cost systems as well as multiservices (voice, data, and multimedia for rural communications. An infrastructure has been deployed in two communities in Cipicung Girang, a village 10 km outside Bandung city, Indonesia. Two towers link the communities with a network of Institut Teknologi Bandung (ITB campus. In addition, local wirelines connect community houses to the network. Currently there are four houses connected to each community node (for a total of eight house, upon which we can perform various tests and measurements.

  11. A Rural Next Generation Network (R-NGN and Its Testbed

    Directory of Open Access Journals (Sweden)

    Armein Z. R. Langi

    2013-09-01

    Full Text Available Rural Next Generation Networks (R-NGN technology allows Internet protocol (IP based systems to be used in rural areas. This paper reports a testbed of R-NGN that uses low cost Ethernet radio links, combined with media gateways and a softswitch. The network consists of point-to-point IP Ethernet 2.4 GHz wireless link, IP switches and gateways in each community, standard copper wires and telephone sets for users. It uses low power consumption, and suitable for low density users. This combination allows low cost systems as well as multiservices (voice, data, and multimedia for rural communications. An infrastructure has been deployed in two communities in Cipicung Girang, a village 10 km outside Bandung city, Indonesia. Two towers link the communities with a network of Institut Teknologi Bandung (ITB campus. In addition, local wirelines connect community houses to the network. Currently there are four houses connected to each community node (for a total of eight house, upon which we can perform various tests and measurements.

  12. [Threats to Identity: A Grounded Theory Approach on Student Nurses' Experience of Incivility during Clinical Placement].

    Science.gov (United States)

    Kang, Jiyeon; Jeong, Yeon Jin; Kong, Kyoung Ran

    2018-02-01

    This qualitative study aimed to explore the experience of incivility among nursing students. Sixteen nursing students who had experienced incivility during their clinical placement were invited for one-on-one interviews until the point of theoretical saturation. The grounded theory approach of Corbin and Strauss was adopted to analyze transcribed interview contents. Incivility occurred in the context of a hierarchical organizational culture, due to nursing students' position as outsiders, non-systematic clinical education, and poor nursing work environment. The experience of incivility was identified as "being mistreated as a marginal person," and nursing students responded to this phenomenon in the following three steps: reality shock, passive action, and submissive acceptance. This process caused students to lose self-esteem and undergo role conflict. Furthermore, nursing students' experience of incivility could eventually lead to workplace bullying in nurses. The results of this study suggest that nursing students' experience of incivility can be a process that threatens their identity. It is necessary to develop educational programs and provide appropriate counseling services so that nursing students can actively cope with the incivility. In addition, institutional plans are needed to ensure safe and supportive clinical learning environments. © 2018 Korean Society of Nursing Science.

  13. Experimental aerodynamic and acoustic model testing of the Variable Cycle Engine (VCE) testbed coannular exhaust nozzle system: Comprehensive data report

    Science.gov (United States)

    Nelson, D. P.; Morris, P. M.

    1980-01-01

    The component detail design drawings of the one sixth scale model of the variable cycle engine testbed demonstrator exhaust syatem tested are presented. Also provided are the basic acoustic and aerodynamic data acquired during the experimental model tests. The model drawings, an index to the acoustic data, an index to the aerodynamic data, tabulated and graphical acoustic data, and the tabulated aerodynamic data and graphs are discussed.

  14. Ground-based PIV and numerical flow visualization results from the Surface Tension Driven Convection Experiment

    Science.gov (United States)

    Pline, Alexander D.; Werner, Mark P.; Hsieh, Kwang-Chung

    1991-01-01

    The Surface Tension Driven Convection Experiment (STDCE) is a Space Transportation System flight experiment to study both transient and steady thermocapillary fluid flows aboard the United States Microgravity Laboratory-1 (USML-1) Spacelab mission planned for June, 1992. One of the components of data collected during the experiment is a video record of the flow field. This qualitative data is then quantified using an all electric, two dimensional Particle Image Velocimetry (PIV) technique called Particle Displacement Tracking (PDT), which uses a simple space domain particle tracking algorithm. Results using the ground based STDCE hardware, with a radiant flux heating mode, and the PDT system are compared to numerical solutions obtained by solving the axisymmetric Navier Stokes equations with a deformable free surface. The PDT technique is successful in producing a velocity vector field and corresponding stream function from the raw video data which satisfactorily represents the physical flow. A numerical program is used to compute the velocity field and corresponding stream function under identical conditions. Both the PDT system and numerical results were compared to a streak photograph, used as a benchmark, with good correlation.

  15. Adding Theoretical Grounding to Grounded Theory: Toward Multi-Grounded Theory

    OpenAIRE

    Göran Goldkuhl; Stefan Cronholm

    2010-01-01

    The purpose of this paper is to challenge some of the cornerstones of the grounded theory approach and propose an extended and alternative approach for data analysis and theory development, which the authors call multi-grounded theory (MGT). A multi-grounded theory is not only empirically grounded; it is also grounded in other ways. Three different grounding processes are acknowledged: theoretical, empirical, and internal grounding. The authors go beyond the pure inductivist approach in GT an...

  16. IN-SITU BIOREMEDIATION OF CONTAMINATED GROUND WATER

    Science.gov (United States)

    This document is one in a series of Ground Water Issue papers which have been prepared in response to needs expressed by the Ground Water Forum. It is based on findings from the research community in concert with experience gained at sites undergoing remediation. the intent of th...

  17. Excitation of the ionospheric Alfvén resonator from the ground: Theory and experiments

    Science.gov (United States)

    Streltsov, A. V.; Chang, C.-L.; Labenski, J.; Milikh, G.; Vartanyan, A.; Snyder, A. L.

    2011-10-01

    We report results from numerical and experimental studies of the excitation of ULF shear Alfvén waves inside the ionospheric Alfvén resonator (IAR) by heating the ionosphere with powerful HF waves launched from the High Frequency Active Auroral Research Program (HAARP) facility in Alaska. Numerical simulations of the two-fluid MHD model describing IAR in a dipole magnetic field geometry with plasma parameters taken from the observations at HAARP during the October-November 2010 experimental campaign reveal that the IAR quality is higher during nighttime conditions, when the ionospheric conductivity is very low. Simulations also reveal that the resonance wave cannot be identified from the magnetic measurements on the ground or at an altitude above 600 km because the magnetic field in this wave has nodes on both ends of the resonator, and the best way to detect IAR modes is by measuring the electric field on low Earth orbit satellites. These theoretical predictions are in good, quantitative agreement with results from observations: In particular, (1) observations from the ground-based magnetometer at the HAARP site demonstrate no significant difference in the amplitudes of the magnetic field generated by HAARP in the frequency range from 0 to 5 Hz, and (2) the DEMETER satellite detected the electric field of the IAR first harmonic at an altitude of 670 km above HAARP during the heating experiment.

  18. Principle and Control Design of Active Ground-Fault Arc Suppression Device for Full Compensation of Ground Current

    DEFF Research Database (Denmark)

    Wang, Wen; Zeng, Xiangjun; Yan, Lingjie

    2017-01-01

    current into the neutral without any large-capacity reactors, and thus avoids the aforementioned overvoltage. It compensates all the active, reactive and harmonic components of the ground current to reliably extinguish the ground-fault arcs. A dual-loop voltage control method is proposed to realize arc...... suppression without capacitive current detection. Its time-based feature also brings the benefit of fast response on ground-fault arc suppression. The principle of full current compensation is analyzed, together with the controller design method of the proposed device. Experiment on a prototype was carried...

  19. Implementation strategies for load center automation on the space station module/power management and distribution testbed

    Science.gov (United States)

    Watson, Karen

    1990-01-01

    The Space Station Module/Power Management and Distribution (SSM/PMAD) testbed was developed to study the tertiary power management on modules in large spacecraft. The main goal was to study automation techniques, not necessarily develop flight ready systems. Because of the confidence gained in many of automation strategies investigated, it is appropriate to study, in more detail, implementation strategies in order to find better trade-offs for nearer to flight ready systems. These trade-offs particularly concern the weight, volume, power consumption, and performance of the automation system. These systems, in their present implementation are described.

  20. Deployment of a Testbed in a Brazilian Research Network using IPv6 and Optical Access Technologies

    Science.gov (United States)

    Martins, Luciano; Ferramola Pozzuto, João; Olimpio Tognolli, João; Chaves, Niudomar Siqueira De A.; Reggiani, Atilio Eduardo; Hortêncio, Claudio Antonio

    2012-04-01

    This article presents the implementation of a testbed and the experimental results obtained with it on the Brazilian Experimental Network of the government-sponsored "GIGA Project." The use of IPv6 integrated to current and emerging optical architectures and technologies, such as dense wavelength division multiplexing and 10-gigabit Ethernet on the core and gigabit capable passive optical network and optical distribution network on access, were tested. These protocols, architectures, and optical technologies are promising and part of a brand new worldwide technological scenario that has being fairly adopted in the networks of enterprises and providers of the world.

  1. Ground Vehicle Power and Mobility Overview - Germany Visit

    Science.gov (United States)

    2011-11-10

    the current and future force Survivability Robotics – Intelligent Systems Vehicle Electronics & Architecture Fuel, Water, Bridging ...Test Cell • Engine Generator Test Lab • Full Vehicle Environmental Test Cell • Hybrid Electric Reconfigurable Moveable Integration Testbed (HERMIT...Converter Conducted competitive runoff evaluations on Bridging Boat engine candidates Completed independent durability assessment of OEM

  2. The development of the human exploration demonstration project (HEDP), a planetary systems testbed

    Science.gov (United States)

    Chevers, Edward S.; Korsmeyer, David J.

    1993-01-01

    The Human Exploration Demonstration Project (HEDP) is an ongoing task at the National Aeronautics and Space Administration's Ames Research Center to address the advanced technology requirements necessary to implement an integrated working and living environment for a planetary surface habitat. The integrated environment will consist of life support systems, physiological monitoring of project crew, a virtual environment workstation, and centralized data acquisition and habitat systems health monitoring. There will be several robotic systems on a simulated planetary landscape external to the habitat environment to provide representative work loads for the crew. This paper describes the status of the HEDP after one year, the major facilities composing the HEDP, the project's role as an Ames Research Center testbed, and the types of demonstration scenarios that will be run to showcase the technologies.

  3. Grounded Theory in Medical Education Research.

    Science.gov (United States)

    Tavakol, Mohsen; Torabi, Sima; Akbar Zeinaloo, Ali

    2006-12-01

    The grounded theory method provides a systematic way to generate theoretical constructs or concepts that illuminate psychosocial processes common to individual who have a similar experience of the phenomenon under investigation. There has been an increase in the number of published research reports that use the grounded theory method. However, there has been less medical education research, which is based on the grounded theory tradition. The purpose of this paper is to introduce basic tenants of qualitative research paradigm with specific reference to ground theory. The paper aims to encourage readers to think how they might possibly use the grounded theory method in medical education research and to apply such a method to their own areas of interest. The important features of a grounded theory as well as its implications for medical education research are explored. Data collection and analysis are also discussed. It seems to be reasonable to incorporate knowledge of this kind in medical education research.

  4. Computation and experiment results of the grounding model of Three Gorges Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Wen Xishan; Zhang Yuanfang; Yu Jianhui; Chen Cixuan [Wuhan University of Hydraulic and Electrical Engineering (China); Qin Liming; Xu Jun; Shu Lianfu [Yangtze River Water Resources Commission, Wuhan (China)

    1999-07-01

    A model for the computation of the grounding parameters of the grids of Three Gorges Power Plant (TGPP) on the Yangtze River is presented in this paper. Using this model computation and analysis of grounding grids is carried out. The results show that reinforcing the grid of the dam is the main body of current dissipation. It must be reliably welded to form a good grounding grid. The experimental results show that the method and program of the computations are correct. (UK)

  5. Attention and competition in figure-ground perception.

    Science.gov (United States)

    Peterson, Mary A; Salvagio, Elizabeth

    2009-01-01

    What are the roles of attention and competition in determining where objects lie in the visual field, a phenomenon known as figure-ground perception? In this chapter, we review evidence that attention and other high-level factors such as familiarity affect figure-ground perception, and we discuss models that implement these effects. Next, we consider the Biased Competition Model of Attention in which attention is used to resolve the competition for neural representation between two nearby stimuli; in this model the response to the stimulus that loses the competition is suppressed. In the remainder of the chapter we discuss recent behavioral evidence that figure-ground perception entails between-object competition in which the response to the shape of the losing competitor is suppressed. We also describe two experiments testing whether more attention is drawn to resolve greater figure-ground competition, as would be expected if the Biased Competition Model of Attention extends to figure-ground perception. In these experiments we find that responses to targets on the location of a losing strong competitor are slowed, consistent with the idea that the location of the losing competitor is suppressed, but responses to targets on the winning competitor are not speeded, which is inconsistent with the hypothesis that attention is used to resolve figure-ground competition. In closing, we discuss evidence that attention can operate by suppression as well as by facilitation.

  6. Grounded theory in music therapy research.

    Science.gov (United States)

    O'Callaghan, Clare

    2012-01-01

    Grounded theory is one of the most common methodologies used in constructivist (qualitative) music therapy research. Researchers use the term "grounded theory" when denoting varying research designs and theoretical outcomes. This may be challenging for novice researchers when considering whether grounded theory is appropriate for their research phenomena. This paper examines grounded theory within music therapy research. Grounded theory is briefly described, including some of its "contested" ideas. A literature search was conducted using the descriptor "music therapy and grounded theory" in Pubmed, CINAHL PsychlNFO, SCOPUS, ERIC (CSA), Web of Science databases, and a music therapy monograph series. A descriptive analysis was performed on the uncovered studies to examine researched phenomena, grounded theory methods used, and how findings were presented, Thirty music therapy research projects were found in refereed journals and monographs from 1993 to "in press." The Strauss and Corbin approach to grounded theory dominates the field. Descriptors to signify grounded theory components in the studies greatly varied. Researchers have used partial or complete grounded theory methods to examine clients', family members', staff, music therapy "overhearers," music therapists', and students' experiences, as well as music therapy creative products and professional views, issues, and literature. Seven grounded theories were offered. It is suggested that grounded theory researchers clarify what and who inspired their design, why partial grounded theory methods were used (when relevant), and their ontology. By elucidating assumptions underpinning the data collection, analysis, and findings' contribution, researchers will continue to improve music therapy research using grounded theory methods.

  7. “Modular Biospheres” New testbed platforms for public environmental education and research

    Science.gov (United States)

    Nelson, M.; Dempster, W. F.; Allen, J. P.

    This paper will review the potential of a relatively new type of testbed platform for environmental education and research because of the unique advantages resulting from their material closure and separation from the outside environment. These facilities which we term "modular biospheres", have emerged from research centered on space life support research but offer a wider range of application. Examples of this type of facility include the Bios-3 facility in Russia, the Japanese CEEF (Closed Ecological Experiment Facility), the NASA Kennedy Space Center Breadboard facility, the Biosphere 2 Test Module and the Laboratory Biosphere. Modular biosphere facilities offer unique research and public real-time science education opportunities. Ecosystem behavior can be studied since initial state conditions can be precisely specified and tracked over different ranges of time. With material closure (apart from very small air exchange rate which can be determined), biogeochemical cycles between soil and soil microorganisms, water, plants, and atmosphere can be studied in detail. Such studies offer a major advance from studies conducted with phytotrons which because of their small size, limit the number of organisms to a very small number, and which crucially do not have a high degree of atmospheric, water and overall material closure. Modular biospheres take advantage of the unique properties of closure, as representing a distinct system "metabolism" and therefore are essentially a "mini-world". Though relatively large in comparison with most phytotrons and ecological microcosms, which are now standard research and educational tools, modular biospheres are small enough that they can be economically reconfigured to reflect a changing research agenda. Some design elements include lighting via electric lights and/or sunlight, hydroponic or soil substrate for plants, opaque or glazed structures, and variable volume chambers or other methods to handle atmospheric pressure

  8. Young Children's Understanding of Cultural Common Ground

    Science.gov (United States)

    Liebal, Kristin; Carpenter, Malinda; Tomasello, Michael

    2013-01-01

    Human social interaction depends on individuals identifying the common ground they have with others, based both on personally shared experiences and on cultural common ground that all members of the group share. We introduced 3- and 5-year-old children to a culturally well-known object and a novel object. An experimenter then entered and asked,…

  9. High Throughput Determination of Plant Height, Ground Cover, and Above-Ground Biomass in Wheat with LiDAR.

    Science.gov (United States)

    Jimenez-Berni, Jose A; Deery, David M; Rozas-Larraondo, Pablo; Condon, Anthony Tony G; Rebetzke, Greg J; James, Richard A; Bovill, William D; Furbank, Robert T; Sirault, Xavier R R

    2018-01-01

    Crop improvement efforts are targeting increased above-ground biomass and radiation-use efficiency as drivers for greater yield. Early ground cover and canopy height contribute to biomass production, but manual measurements of these traits, and in particular above-ground biomass, are slow and labor-intensive, more so when made at multiple developmental stages. These constraints limit the ability to capture these data in a temporal fashion, hampering insights that could be gained from multi-dimensional data. Here we demonstrate the capacity of Light Detection and Ranging (LiDAR), mounted on a lightweight, mobile, ground-based platform, for rapid multi-temporal and non-destructive estimation of canopy height, ground cover and above-ground biomass. Field validation of LiDAR measurements is presented. For canopy height, strong relationships with LiDAR ( r 2 of 0.99 and root mean square error of 0.017 m) were obtained. Ground cover was estimated from LiDAR using two methodologies: red reflectance image and canopy height. In contrast to NDVI, LiDAR was not affected by saturation at high ground cover, and the comparison of both LiDAR methodologies showed strong association ( r 2 = 0.92 and slope = 1.02) at ground cover above 0.8. For above-ground biomass, a dedicated field experiment was performed with destructive biomass sampled eight times across different developmental stages. Two methodologies are presented for the estimation of biomass from LiDAR: 3D voxel index (3DVI) and 3D profile index (3DPI). The parameters involved in the calculation of 3DVI and 3DPI were optimized for each sample event from tillering to maturity, as well as generalized for any developmental stage. Individual sample point predictions were strong while predictions across all eight sample events, provided the strongest association with biomass ( r 2 = 0.93 and r 2 = 0.92) for 3DPI and 3DVI, respectively. Given these results, we believe that application of this system will provide new

  10. Digital Preservation Theory and Application: Transcontinental Persistent Archives Testbed Activity

    Directory of Open Access Journals (Sweden)

    Paul Watry

    2007-12-01

    Full Text Available The National Archives and Records Administration (NARA and EU SHAMAN projects are working with multiple research institutions on tools and technologies that will supply a comprehensive, systematic, and dynamic means for preserving virtually any type of electronic record, free from dependence on any specific hardware or software. This paper describes the joint development work between the University of Liverpool and the San Diego Supercomputer Center (SDSC at the University of California, San Diego on the NARA and SHAMAN prototypes. The aim is to provide technologies in support of the required generic data management infrastructure. We describe a Theory of Preservation that quantifies how communication can be accomplished when future technologies are different from those available at present. This includes not only different hardware and software, but also different standards for encoding information. We describe the concept of a “digital ontology” to characterize preservation processes; this is an advance on the current OAIS Reference Model of providing representation information about records. To realize a comprehensive Theory of Preservation, we describe the ongoing integration of distributed shared collection management technologies, digital library browsing, and presentation technologies for the NARA and SHAMAN Persistent Archive Testbeds.

  11. TORCH Computational Reference Kernels - A Testbed for Computer Science Research

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, Alex; Williams, Samuel Webb; Madduri, Kamesh; Ibrahim, Khaled; Bailey, David H.; Demmel, James W.; Strohmaier, Erich

    2010-12-02

    For decades, computer scientists have sought guidance on how to evolve architectures, languages, and programming models in order to improve application performance, efficiency, and productivity. Unfortunately, without overarching advice about future directions in these areas, individual guidance is inferred from the existing software/hardware ecosystem, and each discipline often conducts their research independently assuming all other technologies remain fixed. In today's rapidly evolving world of on-chip parallelism, isolated and iterative improvements to performance may miss superior solutions in the same way gradient descent optimization techniques may get stuck in local minima. To combat this, we present TORCH: A Testbed for Optimization ResearCH. These computational reference kernels define the core problems of interest in scientific computing without mandating a specific language, algorithm, programming model, or implementation. To compliment the kernel (problem) definitions, we provide a set of algorithmically-expressed verification tests that can be used to verify a hardware/software co-designed solution produces an acceptable answer. Finally, to provide some illumination as to how researchers have implemented solutions to these problems in the past, we provide a set of reference implementations in C and MATLAB.

  12. Ground Based Experiments in Support of Microgravity Research Results-Vapor Growth of Organic Nonlinear Optical Thin Film

    Science.gov (United States)

    Zugrav, M. Ittu; Carswell, William E.; Haulenbeek, Glen B.; Wessling, Francis C.

    2001-01-01

    This work is specifically focused on explaining previous results obtained for the crystal growth of an organic material in a reduced gravity environment. On STS-59, in April 1994, two experiments were conducted with N,N-dimethyl-p-(2,2-dicyanovinyl) aniline (DCVA), a promising nonlinear optical (NLO) material. The space experiments were set to reproduce laboratory experiments that yielded small, bulk crystals of DCVA. The results of the flight experiment, however, were surprising. Rather than producing a bulk single crystal, the result was the production of two high quality, single crystalline thin films. This result was even more intriguing when it is considered that thin films are more desirable for NLO applications than are bulk single crystals. Repeated attempts on the ground to reproduce these results were fruitless. A second set of flight experiments was conducted on STS-69 in September 1995. This time eight DCVA experiments were flown, with each of seven experiments containing a slight change from the first reference experiment. The reference experiment was programmed with growth conditions identical to those of the STS-59 mission. The slight variations in each of the other seven were an attempt to understand what particular parameter was responsible for the preference of thin film growth over bulk crystal growth in microgravity. Once again the results were surprising. In all eight cases thin films were grown again, albeit with varying quality. So now we were faced with a phenomenon that not only takes place in microgravity, but also is very robust, resisting all attempts to force the growth of bulk single crystals.

  13. Design and construction of a testbed for the application of real volcanic ash from the Eyjafjallajökull and Grimsvötn eruptions to microgas turbines

    Science.gov (United States)

    Weber, Konradin; Fischer, Christian; Lange, Martin; Schulz, Uwe; Naraparaju, Ravisankar; Kramer, Dietmar

    2017-04-01

    It is well known that volcanic ash clouds emitted from erupting volcanoes pose a considerable threat to the aviation. The volcanic ash particles can damage the turbine blades and their thermal barrier coatings as well as the bearings of the turbine. For a detailed investigation of this damaging effect a testbed was designed and constructed, which allowed to study the damaging effects of real volcanic ash to an especially for these investigations modified microgas turbine. The use of this microgas turbine had the advantage that it delivers near reality conditions, using kerosene and operating at similar temperatures as big turbines, but at a very cost effective level. The testbed consisted out of a disperser for the real volcanic ash and all the equipment needed to control the micro gas turbine. Moreover, in front and behind the microgas turbine the concentration and the distribution of the volcanic ash were measured online by optical particle counters (OPCs). The particle concentration and size distribution of the volcanic ash particles in the intake in front of the microgas turbine was measured by an optical particle counter (OPC) combined with an isokinetic intake. Behind the microgas turbine in the exhaust gas additionally to the measurement with a second OPC ash particles were caught with an impactor, in order to enable the later analysis with an electron microscope concerning the morphology to verify possible melting processes of the ash particles. This testbed is of high importance as it allows detailed investigations of the impact of volcanic ash to jet turbines and appropriate countermeasures.

  14. Preservation of Multiple Mammalian Tissues to Maximize Science Return from Ground Based and Spaceflight Experiments.

    Science.gov (United States)

    Choi, Sungshin; Ray, Hami E; Lai, San-Huei; Alwood, Joshua S; Globus, Ruth K

    2016-01-01

    Even with recent scientific advancements, challenges posed by limited resources and capabilities at the time of sample dissection continue to limit the collection of high quality tissues from experiments that can be conducted only infrequently and at high cost, such as in space. The resources and time it takes to harvest tissues post-euthanasia, and the methods and duration of long duration storage, potentially have negative impacts on sample quantity and quality, thereby limiting the scientific outcome that can be achieved. The goals of this study were to optimize methods for both sample recovery and science return from rodent experiments, with possible relevance to both ground based and spaceflight studies. The first objective was to determine the impacts of tissue harvest time post-euthanasia, preservation methods, and storage duration, focusing on RNA quality and enzyme activities in liver and spleen as indices of sample quality. The second objective was to develop methods that will maximize science return by dissecting multiple tissues after long duration storage in situ at -80°C. Tissues of C57Bl/6J mice were dissected and preserved at various time points post-euthanasia and stored at -80°C for up to 11 months. In some experiments, tissues were recovered from frozen carcasses which had been stored at -80°C up to 7 months. RNA quantity and quality was assessed by measuring RNA Integrity Number (RIN) values using an Agilent Bioanalyzer. Additionally, the quality of tissues was assessed by measuring activities of hepatic enzymes (catalase, glutathione reductase and GAPDH). Fresh tissues were collected up to one hour post-euthanasia, and stored up to 11 months at -80°C, with minimal adverse effects on the RNA quality of either livers or RNAlater-preserved spleens. Liver enzyme activities were similar to those of positive controls, with no significant effect observed at any time point. Tissues dissected from frozen carcasses that had been stored for up to 7

  15. Analysis, modeling, and simulation (AMS) testbed development and evaluation to support dynamic mobility applications (DMA) and active transportation and demand management (ATDM) programs — evaluation report for ATDM program.

    Science.gov (United States)

    2017-07-16

    The primary objective of this project is to develop multiple simulation testbeds/transportation models to evaluate the impacts of Dynamic Mobility Applications (DMA) and the Active Transportation and Demand Management (ATDM) strategies. Specifically,...

  16. Small Unmanned Aircraft Systems Integration into the National Airspace System Visual-Line-of-Sight Human-in-the-Loop Experiment

    Science.gov (United States)

    Trujillo, Anna C.; Ghatas, Rania W.; Mcadaragh, Raymon; Burdette, Daniel W.; Comstock, James R.; Hempley, Lucas E.; Fan, Hui

    2015-01-01

    As part of the Unmanned Aircraft Systems (UAS) in the National Airspace System (NAS) project, research on integrating small UAS (sUAS) into the NAS was underway by a human-systems integration (HSI) team at the NASA Langley Research Center. Minimal to no research has been conducted on the safe, effective, and efficient manner in which to integrate these aircraft into the NAS. sUAS are defined as aircraft weighing 55 pounds or less. The objective of this human system integration team was to build a UAS Ground Control Station (GCS) and to develop a research test-bed and database that provides data, proof of concept, and human factors guidelines for GCS operations in the NAS. The objectives of this experiment were to evaluate the effectiveness and safety of flying sUAS in Class D and Class G airspace utilizing manual control inputs and voice radio communications between the pilot, mission control, and air traffic control. The design of the experiment included three sets of GCS display configurations, in addition to a hand-held control unit. The three different display configurations were VLOS, VLOS + Primary Flight Display (PFD), and VLOS + PFD + Moving Map (Map). Test subject pilots had better situation awareness of their vehicle position, altitude, airspeed, location over the ground, and mission track using the Map display configuration. This configuration allowed the pilots to complete the mission objectives with less workload, at the expense of having better situation awareness of other aircraft. The subjects were better able to see other aircraft when using the VLOS display configuration. However, their mission performance, as well as their ability to aviate and navigate, was reduced compared to runs that included the PFD and Map displays.

  17. Dynamical response of the Galileo Galilei on the ground rotor to test the equivalence principle: Theory, simulation, and experiment. I. The normal modes

    International Nuclear Information System (INIS)

    Comandi, G.L.; Chiofalo, M.L.; Toncelli, R.; Bramanti, D.; Polacco, E.; Nobili, A.M.

    2006-01-01

    Recent theoretical work suggests that violation of the equivalence principle might be revealed in a measurement of the fractional differential acceleration η between two test bodies-of different compositions, falling in the gravitational field of a source mass--if the measurement is made to the level of η≅10 -13 or better. This being within the reach of ground based experiments gives them a new impetus. However, while slowly rotating torsion balances in ground laboratories are close to reaching this level, only an experiment performed in a low orbit around the Earth is likely to provide a much better accuracy. We report on the progress made with the 'Galileo Galilei on the ground' (GGG) experiment, which aims to compete with torsion balances using an instrument design also capable of being converted into a much higher sensitivity space test. In the present and following articles (Part I and Part II), we demonstrate that the dynamical response of the GGG differential accelerometer set into supercritical rotation-in particular, its normal modes (Part I) and rejection of common mode effects (Part II)-can be predicted by means of a simple but effective model that embodies all the relevant physics. Analytical solutions are obtained under special limits, which provide the theoretical understanding. A simulation environment is set up, obtaining a quantitative agreement with the available experimental data on the frequencies of the normal modes and on the whirling behavior. This is a needed and reliable tool for controlling and separating perturbative effects from the expected signal, as well as for planning the optimization of the apparatus

  18. Grounding in Instant Messaging

    Science.gov (United States)

    Fox Tree, Jean E.; Mayer, Sarah A.; Betts, Teresa E.

    2011-01-01

    In two experiments, we investigated predictions of the "collaborative theory of language use" (Clark, 1996) as applied to instant messaging (IM). This theory describes how the presence and absence of different grounding constraints causes people to interact differently across different communicative media (Clark & Brennan, 1991). In Study 1, we…

  19. Ground Testing a Nuclear Thermal Rocket: Design of a sub-scale demonstration experiment

    Energy Technology Data Exchange (ETDEWEB)

    David Bedsun; Debra Lee; Margaret Townsend; Clay A. Cooper; Jennifer Chapman; Ronald Samborsky; Mel Bulman; Daniel Brasuell; Stanley K. Borowski

    2012-07-01

    In 2008, the NASA Mars Architecture Team found that the Nuclear Thermal Rocket (NTR) was the preferred propulsion system out of all the combinations of chemical propulsion, solar electric, nuclear electric, aerobrake, and NTR studied. Recently, the National Research Council committee reviewing the NASA Technology Roadmaps recommended the NTR as one of the top 16 technologies that should be pursued by NASA. One of the main issues with developing a NTR for future missions is the ability to economically test the full system on the ground. In the late 1990s, the Sub-surface Active Filtering of Exhaust (SAFE) concept was first proposed by Howe as a method to test NTRs at full power and full duration. The concept relied on firing the NTR into one of the test holes at the Nevada Test Site which had been constructed to test nuclear weapons. In 2011, the cost of testing a NTR and the cost of performing a proof of concept experiment were evaluated.

  20. The Fast Alternative Cryogenic Experiment Testbed

    Science.gov (United States)

    Nash, Alfred; Holmes, Warren

    2000-01-01

    One of the challenges in the area of cryogenics for space exploration in the next millennium is providing the capability for inexpensive, frequent, access to space. Faced with this challenge during the International Space Station (ISS) build era, when other Space Shuttle manifesting opportunities are unavailable, a "proof of concept" cryostat has been developed to demonstrate the ability to accommodate low temperature science investigations within the constraints of the Hitchhiker siderail carrier. The Hitchhiker siderail carrier is available on a "mass available" basis during the ISS build era. In fact, several hitchhiker payloads flew with the deployment of the Unity module. Hitchhiker siderail carrier payloads have historically flown an average of about four times a year. A hybrid Solid Neon - Superfluid Helium cryostat has been developed with Janis Research Company to accommodate instruments of 16.5 cm diameter and 30 cm. length. This hybrid approach was taken in part to provide adequate on-orbit lifetime for instruments with high (conducted) heat loads from the instrumentation wiring. Mass, volume, lifetime and the launch hold scenario were all design drivers. In addition, with Ball Aerospace and Technologies Corporation, a multichannel VME architecture Germanium Resistance Thermometer (GRT) readout and heater control servo system has been developed. In a flight system, the cryostat and electronics payloads would be umbilically attached in a paired Hitchhiker siderail mount, and permit on-orbit command and telemetry capability. The results of performance tests of both the cryostat, and a helium sample instrument will be presented. The instrument features a self contained, miniaturized, nano-Kelvin resolution High Resolution Thermometer (HRT). This high level of thermal resolution is achieved through the utilization of a dc Superconducting Quantum Interference Device (SQUID). Although developed for the Low Temperature Microgravity Fundamental Physics investigator community, many design features are applicable in fields such as infrared and x-ray astronomy.

  1. Cryogenic Orbital Testbed (CRYOTE) Ground Test Article, Final Report

    Science.gov (United States)

    Johnson, Wesley L.; Rhys, Noah O.; Bradley, David E.; Wollen, Mark; Kutter, Bernard; Gravlee, Mari; Walls, Laurie K.

    2015-01-01

    Liquid propulsion has been used since Robert Goddard started developing a liquid oxygen (LO2) and gasoline powered rocket and fired it in 1923 (Ref. 1). In the following decades engineers settled on the combination of liquid hydrogen (LH2) and LO2 as the most efficient propellant combination for in-space travel. Due to their low temperatures (LH2 at 20 K and LO2 at 90 K), they require special handling and procedures. General Dynamics began developing LO2 and LH2 upper stages in 1956 in the form of Centaur, these efforts were soon funded by the Department of Defense in conjunction with NASA (beginning in 1958) (Ref. 2). Meanwhile NASA also worked with McDonnell Douglas to develop the SIV-B stage for the Saturn V rocket. In the subsequent years, the engineers were able to push the Centaur to up to 9 hr of orbital lifetime and the SIV-B to up to 6 hr. Due to venting the resultant boil-off from the high heat loads through the foam insulation on the upper stages, both vehicles remained in a settled configuration throughout the flights, thus the two phases of propellant (liquid and vapor) were separated at a known location. The one exception to this were the Titan/Centaur missions, which thanks to the lower boil-off using three layers of multilayer insulation (MLI), were able to coast unsettled for up to 5.25 hr during direct geosynchronous orbit insertion missions. In the years since there has been a continuous effort to extend the life of these upper stages from hours to days or even months.

  2. Trace Gas Measurements from the GeoTASO and GCAS Airborne Instruments: An Instrument and Algorithm Test-Bed for Air Quality Observations from Geostationary Orbit

    Science.gov (United States)

    Nowlan, C. R.; Liu, X.; Janz, S. J.; Leitch, J. W.; Al-Saadi, J. A.; Chance, K.; Cole, J.; Delker, T.; Follette-Cook, M. B.; Gonzalez Abad, G.; Good, W. S.; Kowalewski, M. G.; Loughner, C.; Pickering, K. E.; Ruppert, L.; Soo, D.; Szykman, J.; Valin, L.; Zoogman, P.

    2016-12-01

    The Geostationary Trace gas and Aerosol Sensor Optimization (GeoTASO) and the GEO-CAPE Airborne Simulator (GCAS) instruments are pushbroom sensors capable of making remote sensing measurements of air quality and ocean color. Originally developed as test-bed instruments for the Geostationary Coastal and Air Pollution Events (GEO-CAPE) decadal survey, these instruments are now also part of risk reduction for the upcoming Tropospheric Emissions: Monitoring of Pollution (TEMPO) and Geostationary Environment Monitoring Spectrometer (GEMS) geostationary satellite missions, and will provide validation capabilities after the satellite instruments are in orbit. GeoTASO and GCAS flew on two different aircraft in their first intensive air quality field campaigns during the DISCOVER-AQ missions over Texas in 2013 and Colorado in 2014. GeoTASO was also deployed in 2016 during the KORUS-AQ field campaign to make measurements of trace gases and aerosols over Korea. GeoTASO and GCAS collect spectra of backscattered solar radiation in the UV and visible that can be used to derive 2-D maps of trace gas columns below the aircraft at spatial resolutions on the order of 250 x 500 m. We present spatially resolved maps of trace gas retrievals of ozone, nitrogen dioxide, formaldehyde and sulfur dioxide over urban areas and power plants from flights during the field campaigns, and comparisons with data from ground-based spectrometers, in situ monitoring instruments, and satellites.

  3. Familiar shapes attract attention in figure-ground displays.

    Science.gov (United States)

    Nelson, Rolf A; Palmer, Stephen E

    2007-04-01

    We report five experiments that explore the effect of figure-ground factors on attention. We hypothesized that figural cues, such as familiar shape, would draw attention to the figural side in an attentional cuing task using bipartite figure-ground displays. The first two experiments used faces in profile as the familiar shape and found a perceptual advantage for targets presented on the meaningful side of the central contour in detection speed (Experiment 1) and discrimination accuracy (Experiment 2). The third experiment demonstrated the figural advantage in response time (RT) with nine other familiar shapes (including a sea horse, a guitar, a fir tree, etc.), but only when targets appeared in close proximity to the contour. A fourth experiment obtained a figural advantage in a discrimination task with the larger set of familiar shapes. The final experiment ruled out eye movements as a possible confounding factor by replicating the RT advantage for targets on the figural side of face displays when all trials containing eye movements were eliminated. The results are discussed in terms of ecological influences on attention, and are cast within the framework of Yantis and Jonides's hypothesis that attention is exogenously drawn to the onset of new perceptual objects. We argue that the figural side constitutes an "object" whereas the ground side does not, and that figural cues such as shape familiarity are effective in determining which areas represent objects.

  4. LEO-to-ground optical communications using SOTA (Small Optical TrAnsponder) - Payload verification results and experiments on space quantum communications

    Science.gov (United States)

    Carrasco-Casado, Alberto; Takenaka, Hideki; Kolev, Dimitar; Munemasa, Yasushi; Kunimori, Hiroo; Suzuki, Kenji; Fuse, Tetsuharu; Kubo-Oka, Toshihiro; Akioka, Maki; Koyama, Yoshisada; Toyoshima, Morio

    2017-10-01

    Free-space optical communications have held the promise of revolutionizing space communications for a long time. The benefits of increasing the bitrate while reducing the volume, mass and energy of the space terminals have attracted the attention of many researchers for a long time. In the last few years, more and more technology demonstrations have been taking place with participants from both the public and the private sector. The National Institute of Information and Communications Technology (NICT) in Japan has a long experience in this field. SOTA (Small Optical TrAnsponder) was the last NICT space lasercom mission, designed to demonstrate the potential of this technology applied to microsatellites. Since the beginning of SOTA mission in 2014, NICT regularly established communication using the Optical Ground Stations (OGS) located in the Headquarters at Koganei (Tokyo) to receive the SOTA signals, with over one hundred successful links. All the goals of the SOTA mission were fulfilled, including up to 10-Mbit/s downlinks using two different wavelengths and apertures, coarse and fine tracking of the OGS beacon, space-to-ground transmission of the on-board-camera images, experiments with different error correcting codes, interoperability with other international OGS, and experiments on quantum communications. The SOTA mission ended on November 2016, more than doubling the designed lifetime of 1-year. In this paper, the SOTA characteristics and basic operation are explained, along with the most relevant technological demonstrations.

  5. Resolution of holograms produced by the fluid experiment system and the holography ground system

    Science.gov (United States)

    Brooks, Howard L.

    1987-01-01

    The Fluid Experiment System (FES) was developed to study low temperature crystal growth of triglycine sulfate from solution in a low gravity environment onboard Spacelab. The first flight of FES was in 1985. FES uses an optical system to take holograms of the growing crystal to be analyzed after the mission in the Holography Ground System (HGS) located in the Test Laboratory at Marshall Space Flight Center. Microscopic observation of the images formed by the reconstructed holograms is critical to determining crystal growth rate and particle velocity. FES and HGS were designed for a resolution of better than 20 micrometers, but initial observation of the flight holograms show a limit of 80 micrometers. The resolution of the FES holograms is investigated, as well as the role of beam intensity ratio and exposure time on the resolution of HGS produced holograms.

  6. Making sense of grounded theory in medical education.

    Science.gov (United States)

    Kennedy, Tara J T; Lingard, Lorelei A

    2006-02-01

    Grounded theory is a research methodology designed to develop, through collection and analysis of data that is primarily (but not exclusively) qualitative, a well-integrated set of concepts that provide a theoretical explanation of a social phenomenon. This paper aims to provide an introduction to key features of grounded theory methodology within the context of medical education research. In this paper we include a discussion of the origins of grounded theory, a description of key methodological processes, a comment on pitfalls encountered commonly in the application of grounded theory research, and a summary of the strengths of grounded theory methodology with illustrations from the medical education domain. The significant strengths of grounded theory that have resulted in its enduring prominence in qualitative research include its clearly articulated analytical process and its emphasis on the generation of pragmatic theory that is grounded in the data of experience. When applied properly and thoughtfully, grounded theory can address research questions of significant relevance to the domain of medical education.

  7. Making Things Right: Nurses' Experiences with Workplace Bullying—A Grounded Theory

    Science.gov (United States)

    Gaffney, Donna A.; DeMarco, Rosanna F.; Hofmeyer, Anne; Vessey, Judith A.; Budin, Wendy C.

    2012-01-01

    While bullying in the healthcare workplace has been recognized internationally, there is still a culture of silence in many institutions in the United States, perpetuating underreporting and insufficient and unproven interventions. The deliberate, repetitive, and aggressive behaviors of bullying can cause psychological and/or physical harm among professionals, disrupt nursing care, and threaten patient safety and quality outcomes. Much of the literature focuses on categories of bullying behaviors and nurse responses. This qualitative study reports on the experiences of nurses confronting workplace bullying. We collected data from the narratives of 99 nurses who completed an open-ended question embedded in an online survey in 2007. A constructivist grounded theory approach was used to analyze the data and shape a theory of how nurses make things right when confronted with bullying. In a four-step process, nurses place bullying in context, assess the situation, take action, and judge the outcomes of their actions. While many nurses do engage in a number of effective yet untested strategies, two additional concerns remain: inadequate support among nursing colleagues and silence and inaction by nurse administrators. Qualitative inquiry has the potential to guide researchers to a greater understanding of the complexities of bullying in the workplace. PMID:22567223

  8. Making Things Right: Nurses' Experiences with Workplace Bullying—A Grounded Theory

    Directory of Open Access Journals (Sweden)

    Donna A. Gaffney

    2012-01-01

    Full Text Available While bullying in the healthcare workplace has been recognized internationally, there is still a culture of silence in many institutions in the United States, perpetuating underreporting and insufficient and unproven interventions. The deliberate, repetitive, and aggressive behaviors of bullying can cause psychological and/or physical harm among professionals, disrupt nursing care, and threaten patient safety and quality outcomes. Much of the literature focuses on categories of bullying behaviors and nurse responses. This qualitative study reports on the experiences of nurses confronting workplace bullying. We collected data from the narratives of 99 nurses who completed an open-ended question embedded in an online survey in 2007. A constructivist grounded theory approach was used to analyze the data and shape a theory of how nurses make things right when confronted with bullying. In a four-step process, nurses place bullying in context, assess the situation, take action, and judge the outcomes of their actions. While many nurses do engage in a number of effective yet untested strategies, two additional concerns remain: inadequate support among nursing colleagues and silence and inaction by nurse administrators. Qualitative inquiry has the potential to guide researchers to a greater understanding of the complexities of bullying in the workplace.

  9. An Experience of an Individual With a Chronic Wound in an Open Abdomen: A Grounded Theory.

    Science.gov (United States)

    Fuentes-Ramírez, Alejandra

    2017-06-01

    The open abdomen (OA) surgical technique has become an option for treating complex abdominal injuries; however, complications leading to late closure conditions might arise. In these cases the wound must be left open, which greatly impacts the patient's life. The author aims to describe the experiences of individuals with a chronic OA wound. Qualitative design using grounded theory was utilized. This study was carried out with a group of 28 adults who were treated with OA technique and whose wound had remained open for more than a month in duration and only received outpatient wound care. Data were collected through open interviews and examined under continuous comparison. The average age of the respondents was 45 years, and their wound, treated with OA due to severe abdominal infection, remained open between 2 months and 8 years. An emergent theory was developed to describe how people facing this experience undergo a process of 4 stages: 1) finding an OA wound upon waking, 2) feeling desperate about the healing process and the limitations involved, 3) regaining control of their life, and 4) taking advantage of their second chance at life with an OA wound. This study provides insight for nurses and other health care professionals into the experiences of patients with a chronic OA wound and proposes an emerging theory based on the conceptualization of these experiences.

  10. A focal plane metrology system and PSF centroiding experiment

    Science.gov (United States)

    Li, Haitao; Li, Baoquan; Cao, Yang; Li, Ligang

    2016-10-01

    In this paper, we present an overview of a detector array equipment metrology testbed and a micro-pixel centroiding experiment currently under development at the National Space Science Center, Chinese Academy of Sciences. We discuss on-going development efforts aimed at calibrating the intra-/inter-pixel quantum efficiency and pixel positions for scientific grade CMOS detector, and review significant progress in achieving higher precision differential centroiding for pseudo star images in large area back-illuminated CMOS detector. Without calibration of pixel positions and intrapixel response, we have demonstrated that the standard deviation of differential centroiding is below 2.0e-3 pixels.

  11. Large-scale, high-performance and cloud-enabled multi-model analytics experiments in the context of the Earth System Grid Federation

    Science.gov (United States)

    Fiore, S.; Płóciennik, M.; Doutriaux, C.; Blanquer, I.; Barbera, R.; Williams, D. N.; Anantharaj, V. G.; Evans, B. J. K.; Salomoni, D.; Aloisio, G.

    2017-12-01

    The increased models resolution in the development of comprehensive Earth System Models is rapidly leading to very large climate simulations output that pose significant scientific data management challenges in terms of data sharing, processing, analysis, visualization, preservation, curation, and archiving.Large scale global experiments for Climate Model Intercomparison Projects (CMIP) have led to the development of the Earth System Grid Federation (ESGF), a federated data infrastructure which has been serving the CMIP5 experiment, providing access to 2PB of data for the IPCC Assessment Reports. In such a context, running a multi-model data analysis experiment is very challenging, as it requires the availability of a large amount of data related to multiple climate models simulations and scientific data management tools for large-scale data analytics. To address these challenges, a case study on climate models intercomparison data analysis has been defined and implemented in the context of the EU H2020 INDIGO-DataCloud project. The case study has been tested and validated on CMIP5 datasets, in the context of a large scale, international testbed involving several ESGF sites (LLNL, ORNL and CMCC), one orchestrator site (PSNC) and one more hosting INDIGO PaaS services (UPV). Additional ESGF sites, such as NCI (Australia) and a couple more in Europe, are also joining the testbed. The added value of the proposed solution is summarized in the following: it implements a server-side paradigm which limits data movement; it relies on a High-Performance Data Analytics (HPDA) stack to address performance; it exploits the INDIGO PaaS layer to support flexible, dynamic and automated deployment of software components; it provides user-friendly web access based on the INDIGO Future Gateway; and finally it integrates, complements and extends the support currently available through ESGF. Overall it provides a new "tool" for climate scientists to run multi-model experiments. At the

  12. Flight Experiments for Living With a Star Space Environment Testbed (LWS-SET): Relationship to Technology

    Science.gov (United States)

    LaBel, Kenneth A.; Barth, Janet L.; Brewer, Dana A.

    2003-01-01

    This viewgraph presentation provides information on flight validation experiments for technologies to determine solar effects. The experiments are intended to demonstrate tolerance to a solar variant environment. The technologies tested are microelectronics, photonics, materials, and sensors.

  13. Space Telecommunications Radio System (STRS) Architecture. Part 1; Tutorial - Overview

    Science.gov (United States)

    Handler, Louis M.; Briones, Janette C.; Mortensen, Dale J.; Reinhart, Richard C.

    2012-01-01

    Space Telecommunications Radio System (STRS) Architecture Standard provides a NASA standard for software-defined radio. STRS is being demonstrated in the Space Communications and Navigation (SCaN) Testbed formerly known as Communications, Navigation and Networking Configurable Testbed (CoNNeCT). Ground station radios communicating the SCaN testbed are also being written to comply with the STRS architecture. The STRS Architecture Tutorial Overview presents a general introduction to the STRS architecture standard developed at the NASA Glenn Research Center (GRC), addresses frequently asked questions, and clarifies methods of implementing the standard. The STRS architecture should be used as a base for many of NASA s future telecommunications technologies. The presentation will provide a basic understanding of STRS.

  14. Living with a Star Space Environment Testbed

    Science.gov (United States)

    Barth, Janet

    2003-01-01

    Summary of activities: (1) FYO1 NRA - Model development and data mining. (2) FY03 NRA - Flight investigations. (3) SET carrier development. (4) Study for accommodation of SET carrier to support advanced detectors. (5) Collaboration with other programs: LWS TR&T to maximize synergy between TR&T space environment research and SET space environment effects research. LWS Data System to optimize dissemination of SET data. NASA Electronic Parts and Packaging Program to leverage ground testing of technologies. Defense Threat Reduction Agency to leverage ground testing and common interests in advanced detectors. and Air Force Research Laboratory to leverage flight opportunities. (6) Education and Public Outreach.

  15. Managing preconceived expectations: mental health service users experiences of going home from hospital: a grounded theory study.

    Science.gov (United States)

    Keogh, B; Callaghan, P; Higgins, A

    2015-11-01

    What is known on the subject? The time of discharge from a mental health hospital can be challenging for mental health service users, with high rates of readmission in the immediate months following discharge. Although some research exists that explores service users' perspectives of being discharged, little evidence exists that explores the processes influencing or used by service users' to adapt to the transition from in-patient acute mental health service. What this papers adds to existing knowledge? The findings of this grounded theory study demonstrates the strategies service users used to managed their own, as well as their social audiences, preconceived expectations arising from their new identity as 'psychiatric patients' following their discharge from hospital. While there is a move to develop recovery-orientated mental health services, key indicators of recovery-oriented practices were often absent from service users' experiences of service provision. What are the implications for practice? Nurses and other mental health professionals need to recognize their contribution to the architecture of stigma that transcends the physical structures of hospital or ward and are entrenched within attitudes, interactions and practices. The findings of this study can provide guidance to those working with service users and help them to understand the complexities of their experiences when using mental health services, which go far beyond the management of their symptoms. Following a period of hospitalization, the transition to home can result in increased vulnerability and a source of stress for mental health service users. Readmission rates have been suggested as one indicator of the success of the transition from hospital to community care. Despite knowledge of some of the factors that impact on service users following discharge, no coherent model or theoretical framework could be located in the literature, which explains or aides an in-depth understanding of the

  16. Fault Detection, Isolation and Recovery (FDIR) Portable Liquid Oxygen Hardware Demonstrator

    Science.gov (United States)

    Oostdyk, Rebecca L.; Perotti, Jose M.

    2011-01-01

    The Fault Detection, Isolation and Recovery (FDIR) hardware demonstration will highlight the effort being conducted by Constellation's Ground Operations (GO) to provide the Launch Control System (LCS) with system-level health management during vehicle processing and countdown activities. A proof-of-concept demonstration of the FDIR prototype established the capability of the software to provide real-time fault detection and isolation using generated Liquid Hydrogen data. The FDIR portable testbed unit (presented here) aims to enhance FDIR by providing a dynamic simulation of Constellation subsystems that feed the FDIR software live data based on Liquid Oxygen system properties. The LO2 cryogenic ground system has key properties that are analogous to the properties of an electronic circuit. The LO2 system is modeled using electrical components and an equivalent circuit is designed on a printed circuit board to simulate the live data. The portable testbed is also be equipped with data acquisition and communication hardware to relay the measurements to the FDIR application running on a PC. This portable testbed is an ideal capability to perform FDIR software testing, troubleshooting, training among others.

  17. Investigating the dimension of time: findings from a modified grounded theory study about clients' experiences and descriptions of temporality or time within music therapy.

    Science.gov (United States)

    Daveson, Barbara; O'Callaghan, Clare

    2011-01-01

    Many references to time or temporality are located within music therapy literature, however little research has been completed regarding this phenomenon. Findings from a modified grounded theory study about clients' experiences and descriptions of time within the context of music therapy are presented here. The study was informed by the constructivist-interpretive paradigm and a grounded-descriptive statement finding resulted. A 2-staged research methodology was used, comprising a deductive-inductive content analysis of information from the public domain, followed by data-mining of information from a minimum of 160 clients and analysis of data from at least 43 of these 160 clients. Information regarding memory experiences, the duration of music therapy effects, recall and retrieval, and experiences of time are identified. Implications for practice are emphasized, in particular the following is stressed (a) the importance of time orientation and temporal connectedness in relation to identity development, (b) temporal strategies within music experience to assist integration, recall, and retrieval of information, and (c) the importance of and the elements involved in time modification. New explanations for music therapy phenomena are shared, and areas for research highlighted. Benefits of using time dynamically to aid therapeutic process are proposed, and it is concluded that temporal experience within the context of music therapy is important in relation to both practice and research.

  18. A Study on the Improvement Effect and Field Applicability of the Deep Soft Ground by Ground Heating Method

    Directory of Open Access Journals (Sweden)

    Mincheol Park

    2018-05-01

    Full Text Available The soft ground in coastal areas should be treated when it needs to be used for the sustainably developed of urban or industrial complex constructions. The ground heating method for soft ground improvement was applied in Eastern Europe in the 1960s, but it was not widely used due to economic and environmental problems. The author developed a device for improving soft ground using an electric heating pipe. This paper investigates the improvement effect and field application of deep soft ground by the ground heating method using the electric heating pipe. Ground heating increases the temperature of the deep soft ground and increases the tip resistance of the static electronic piezo-cone penetration test. Additionally, the pressure of the pore water decreases because the pore water is evaporated due to the ground heating. As a result of the experiment, it was verified that there was an improvement in the effect of deep soft ground by the ground heating method. With ground heating for 96 h, the tip resistance was increased by 61% at a point 0.35 m horizontally away from the electric heat pipe, 22% at 0.97 m, and 2% at 1.31 m. As a result of the field test, it was found that there were no problems in the power supply of the diesel generator and the control panel. It was easy to install the electric heating pipes in the deep soft ground. However, due to boring, the ground was disturbed and water vapor was discharged through this gap. To minimize the discharge of water vapor, it is necessary to drive the electric heating pipe.

  19. Cryogenics Testbed Laboratory Flange Baseline Configuration

    Science.gov (United States)

    Acuna, Marie Lei Ysabel D.

    2013-01-01

    As an intern at Kennedy Space Center (KSC), I was involved in research for the Fluids and Propulsion Division of the NASA Engineering (NE) Directorate. I was immersed in the Integrated Ground Operations Demonstration Units (IGODU) project for the majority of my time at KSC, primarily with the Ground Operations Demonstration Unit Liquid Oxygen (GODU L02) branch of IGODU. This project was established to develop advancements in cryogenic systems as a part of KSC's Advanced Exploration Systems (AES) program. The vision of AES is to develop new approaches for human exploration, and operations in and beyond low Earth orbit. Advanced cryogenic systems are crucial to minimize the consumable losses of cryogenic propellants, develop higher performance launch vehicles, and decrease operations cost for future launch programs. During my internship, I conducted a flange torque tracking study that established a baseline configuration for the flanges in the Simulated Propellant Loading System (SPLS) at the KSC Cryogenics Test Laboratory (CTL) - the testing environment for GODU L02.

  20. Ad Hoc on-Demand Distance Vector (AODV Routing Protocol Performance Evaluation on Hybrid Ad Hoc Network: Comparison of Result of Ns-2 Simulation and Implementation on Testbed using PDA

    Directory of Open Access Journals (Sweden)

    Riri Sari

    2010-10-01

    Full Text Available In Mobile Ad hoc NETwork (MANET, node supplemented with wireless equipment has the capacity to manage and organise autonomously, without the presence of network infrastructures. Hybrid ad hoc network, enable several nodes to move freely (mobile to create instant communication. Independent from infrastructure. They could access the Local Area Network (LAN or the Internet. Functionalities of ad hoc network very much dependent on the routing protocol that determines the routing around node. Ad hoc On-demand Distance Vector (AODV is one of routing protocols in ad hoc network which has a reactive characteristic. This protocol is the most common protocol being researched and used. In this Research, AODV protocol investigation was conducted by developing a testbed using Personal Computer, several Laptops (the Linux Red Hat operation system 9.0 and Fedora Core 2, and Personal Digital Assistant (PDA. This research also made a complete package by mean of cross compilation for PDA iPAQ. In general, results obtained from the simulation of AODV protocol using Network Simulator NS-2 are packet delivery ratio 99.89%, end-to-end delay of 0.14 seconds and routing overhead of 1,756.61 byte per second. Afterwards results from simulation were compared to results from testbed. Results obtained from testbed are as follows: the packet delivery ratio is 99.57%, the end-to-end delay is 1.004 seconds and the routing overhead is 1,360.36 byte per second.

  1. TFTR grounding scheme and ground-monitor system

    International Nuclear Information System (INIS)

    Viola, M.

    1983-01-01

    The Tokamak Fusion Test Reactor (TFTR) grounding system utilizes a single-point ground. It is located directly under the machine, at the basement floor level, and is tied to the building perimeter ground. Wired to this single-point ground, via individual 500 MCM insulated cables, are: the vacuum vessel; four toroidal field coil cases/inner support structure quadrants; umbrella structure halves; the substructure ring girder; radial beams and columns; and the diagnostic systems. Prior to the first machine operation, a ground-loop removal program was initiated. It required insulation of all hangers and supports (within a 35-foot radius of the center of the machine) of the various piping, conduits, cable trays, and ventilation systems. A special ground-monitor system was designed and installed. It actively monitors each of the individual machine grounds to insure that there are no inadvertent ground loops within the machine structure or its ground and that the machine grounds are intact prior to each pulse. The TFTR grounding system has proven to be a very manageable system and one that is easy to maintain

  2. Dismounted Infantry Visualization Research: The Dismounted Infantry Simulation (DISim)

    National Research Council Canada - National Science Library

    Thomas, Mark

    2002-01-01

    .... Targeted to the simulation needs of the ground warfighter, the algorithms developed using the DISim test-bed are high-resolution real-time effects for simulation, training, and mission rehearsal. C++...

  3. Extrasolar Planetary Imaging Coronagraph (EPIC): visible nulling cornagraph testbed results

    Science.gov (United States)

    Lyon, Richard G.; Clampin, Mark; Melnick, Gary; Tolls, Volker; Woodruff, Robert; Vasudevan, Gopal

    2008-07-01

    The Extrasolar Planetary Imaging Coronagraph (EPIC) is a NASA Astrophysics Strategic Mission Concept under study for the upcoming Exoplanet Probe. EPIC's mission would be to image and characterize extrasolar giant planets, and potential super-Earths, in orbits with semi-major axes between 2 and 10 AU. EPIC will provide insights into the physical nature of a variety of planets in other solar systems complimenting radial velocity (RV) and astrometric planet searches. It will detect and characterize the atmospheres of planets identified by radial velocity surveys and potentially some transits, determine orbital inclinations and masses, characterize the atmospheres of gas giants around A and F stars, observed the inner spatial structure and colors of inner Spitzer selected debris disks. EPIC would be launched into a heliocentric Earth trailing drift-away orbit, with a 3-year mission lifetime (5 year goal) and will revisit planets at least three times. The starlight suppression approach consists of a visible nulling coronagraph (VNC) that enables high order starlight suppression in broadband light. To demonstrate the VNC approach and advance it's technology readiness the NASA/Goddard Space Flight Center and Lockheed-Martin have developed a laboratory VNC and have demonstrated white light nulling. We will discuss our ongoing VNC work and show the latest results from the VNC testbed.

  4. Australian perioperative nurses' experiences of assisting in multi-organ procurement surgery: a grounded theory study.

    Science.gov (United States)

    Smith, Zaneta; Leslie, Gavin; Wynaden, Dianne

    2015-03-01

    Multi-organ procurement surgical procedures through the generosity of deceased organ donors, have made an enormous impact on extending the lives of recipients. There is a dearth of in-depth knowledge relating to the experiences of perioperative nurses working closely with organ donors undergoing multi-organ procurement surgical procedures. The aim of this study was to address this gap by describing the perioperative nurses experiences of participating in multi-organ procurement surgical procedures and interpreting these findings as a substantive theory. This qualitative study used grounded theory methodology to generate a substantive theory of the experiences of perioperative nurses participating in multi-organ procurement surgery. Recruitment of participants took place after the study was advertised via a professional newsletter and journal. The study was conducted with participants from metropolitan, rural and regional areas of two Australian states; New South Wales and Western Australia. Thirty five perioperative nurse participants with three to 39 years of professional nursing experience informed the study. Semi structured in-depth interviews were undertaken from July 2009 to April 2010 with a mean interview time of 60 min. Interview data was transcribed verbatim and analysed using the constant comparative method. The study results draw attention to the complexities that exist for perioperative nurses when participating in multi-organ procurement surgical procedures reporting a basic social psychological problem articulated as hiding behind a mask and how they resolved this problem by the basic social psychological process of finding meaning. This study provides a greater understanding of how these surgical procedures impact on perioperative nurses by providing a substantive theory of this experience. The findings have the potential to guide further research into this challenging area of nursing practice with implications for clinical initiatives, management

  5. Autonomous Satellite Command and Control Through the World Wide Web. Phase 3

    Science.gov (United States)

    Cantwell, Brian; Twiggs, Robert

    1998-01-01

    The Automated Space System Experimental Testbed (ASSET) system is a simple yet comprehensive real-world operations network being developed. Phase 3 of the ASSET Project was January-December 1997 and is the subject of this report. This phase permitted SSDL and its project partners to expand the ASSET system in a variety of ways. These added capabilities included the advancement of ground station capabilities, the adaptation of spacecraft on-board software, and the expansion of capabilities of the ASSET management algorithms. Specific goals of Phase 3 were: (1) Extend Web-based goal-level commanding for both the payload PI and the spacecraft engineer. (2) Support prioritized handling of multiple (PIs) Principle Investigators as well as associated payload experimenters. (3) Expand the number and types of experiments supported by the ASSET system and its associated spacecraft. (4) Implement more advanced resource management, modeling and fault management capabilities that integrate the space and ground segments of the space system hardware. (5) Implement a beacon monitoring test. (6) Implement an experimental blackboard controller for space system management. (7) Further define typical ground station developments required for Internet-based remote control and for full system automation of the PI-to-spacecraft link. Each of those goals are examined. Significant sections of this report were also published as a conference paper. Several publications produced in support of this grant are included as attachments. Titles include: 1) Experimental Initiatives in Space System Operations; 2) The ASSET Client Interface: Balancing High Level Specification with Low Level Control; 3) Specifying Spacecraft Operations At The Product/Service Level; 4) The Design of a Highly Configurable, Reusable Operating System for Testbed Satellites; 5) Automated Health Operations For The Sapphire Spacecraft; 6) Engineering Data Summaries for Space Missions; and 7) Experiments In Automated Health

  6. Automated tools and techniques for distributed Grid Software Development of the testbed infrastructure

    CERN Document Server

    Aguado Sanchez, C

    2007-01-01

    Grid technology is becoming more and more important as the new paradigm for sharing computational resources across different organizations in a secure way. The great powerfulness of this solution, requires the definition of a generic stack of services and protocols and this is the scope of the different Grid initiatives. As a result of international collaborations for its development, the Open Grid Forum created the Open Grid Services Architecture (OGSA) which aims to define the common set of services that will enable interoperability across the different implementations. This master thesis has been developed in this framework, as part of the two European-funded projects ETICS and OMII-Europe. The main objective is to contribute to the design and maintenance of large distributed development projects with the automated tool that enables to implement Software Engineering techniques oriented to achieve an acceptable level of quality at the release process. Specifically, this thesis develops the testbed concept a...

  7. Radioactive waste disposal into the ground

    International Nuclear Information System (INIS)

    1965-01-01

    Disposal into ground has sometimes proved to be an expedient and simple method. Where ground disposal has become an established practice, the sites have so far been limited to those remote from population centres; but in other respects, such as in climate and soil conditions, their characteristics vary widely. Experience gained at these sites has illustrated the variety of problems in radioactive waste migration and the resulting pollution and environmental radiation levels that may reasonably be anticipated at other sites, whether remote from population centres or otherwise.

  8. The GridEcon Platform: A Business Scenario Testbed for Commercial Cloud Services

    Science.gov (United States)

    Risch, Marcel; Altmann, Jörn; Guo, Li; Fleming, Alan; Courcoubetis, Costas

    Within this paper, we present the GridEcon Platform, a testbed for designing and evaluating economics-aware services in a commercial Cloud computing setting. The Platform is based on the idea that the exact working of such services is difficult to predict in the context of a market and, therefore, an environment for evaluating its behavior in an emulated market is needed. To identify the components of the GridEcon Platform, a number of economics-aware services and their interactions have been envisioned. The two most important components of the platform are the Marketplace and the Workflow Engine. The Workflow Engine allows the simple composition of a market environment by describing the service interactions between economics-aware services. The Marketplace allows trading goods using different market mechanisms. The capabilities of these components of the GridEcon Platform in conjunction with the economics-aware services are described in this paper in detail. The validation of an implemented market mechanism and a capacity planning service using the GridEcon Platform also demonstrated the usefulness of the GridEcon Platform.

  9. Time Distribution Using SpaceWire in the SCaN Testbed on ISS

    Science.gov (United States)

    Lux, James P.

    2012-01-01

    A paper describes an approach for timekeeping and time transfer among the devices on the CoNNeCT project s SCaN Testbed. It also describes how the clocks may be synchronized with an external time reference; e.g., time tags from the International Space Station (ISS) or RF signals received by a radio (TDRSS time service or GPS). All the units have some sort of counter that is fed by an oscillator at some convenient frequency. The basic problem in timekeeping is relating the counter value to some external time standard such as UTC. With SpaceWire, there are two approaches possible: one is to just use SpaceWire to send a message, and use an external wire for the sync signal. This is much the same as with the RS- 232 messages and l pps line from a GPS receiver. However, SpaceWire has an additional capability that was added to make it easier - it can insert and receive a special "timecode" word in the data stream.

  10. Laser communication experiments between Sota and Meo optical ground station

    Science.gov (United States)

    Artaud, G.,; Issler, J.-L.; Védrenne, N.; Robert, C.; Petit, C.; Samain, E.; Phung, D.-H.; Maurice, N.; Toyoshima, M.; Kolev, D.

    2017-09-01

    Optical transmissions between earth and space have been identified as key technologies for future high data rate transmissions between satellites and ground. CNES is investigating the use of optics both for High data rate direct to Earth transfer from observation satellites in LEO, and for future telecommunications applications using optics for the high capacity Gateway link.

  11. Ion beam analysis of ground coffee and roasted coffee beans

    International Nuclear Information System (INIS)

    Debastiani, R.; Santos, C.E.I. dos; Yoneama, M.L.; Amaral, L.; Dias, J.F.

    2014-01-01

    The way that coffee is prepared (using roasted ground coffee or roasted coffee beans) may influence the quality of beverage. Therefore, the aim of this work is to use ion beam techniques to perform a full elemental analysis of packed roasted ground coffee and packed roasted coffee beans, as well as green coffee beans. The samples were analyzed by PIXE (particle-induced X-ray emission). Light elements were measured through RBS (Rutherford backscattering spectrometry) experiments. Micro-PIXE experiments were carried out in order to check the elemental distribution in the roasted and green coffee beans. In general, the elements found in ground coffee were Mg, P, S, Cl, K, Ca, Ti, Mn, Fe, Cu, Zn, Rb and Sr. A comparison between ground coffee and grinded roasted beans shows significant differences for several elements. Elemental maps reveal that P and K are correlated and practically homogeneously distributed over the beans

  12. Ion beam analysis of ground coffee and roasted coffee beans

    Energy Technology Data Exchange (ETDEWEB)

    Debastiani, R., E-mail: rafa_debas@yahoo.com.br; Santos, C.E.I. dos; Yoneama, M.L.; Amaral, L.; Dias, J.F.

    2014-01-01

    The way that coffee is prepared (using roasted ground coffee or roasted coffee beans) may influence the quality of beverage. Therefore, the aim of this work is to use ion beam techniques to perform a full elemental analysis of packed roasted ground coffee and packed roasted coffee beans, as well as green coffee beans. The samples were analyzed by PIXE (particle-induced X-ray emission). Light elements were measured through RBS (Rutherford backscattering spectrometry) experiments. Micro-PIXE experiments were carried out in order to check the elemental distribution in the roasted and green coffee beans. In general, the elements found in ground coffee were Mg, P, S, Cl, K, Ca, Ti, Mn, Fe, Cu, Zn, Rb and Sr. A comparison between ground coffee and grinded roasted beans shows significant differences for several elements. Elemental maps reveal that P and K are correlated and practically homogeneously distributed over the beans.

  13. Analysis of solar thermophotovoltaic test data from experiments performed at McDonnell Douglas

    Energy Technology Data Exchange (ETDEWEB)

    Stone, K.W.; Kusek, S.M.; Drubka, R.E. [McDonnell Douglas, 5301 Bolsa Avenue, Huntington Beach, California 92647 (United States); Fay, T.D. [21911 Bacalar, Mission Viejo, California 92692 (United States)

    1995-01-05

    Solar thermophotovoltaic power systems offer potentially high system efficiency for solar energy to electrical energy conversion and attractive system advantages. McDonnell Douglas Corporation (MDC) has been investigating this technology for both space and terrestrial applications for several years. A testbed prototype was designed, built, and tested on a 90 kW{sub t} dish concentrator at the MDA solar test facility. Twelve experiments were conducted with absorber temperatures in excess of 1300 {degree}C being achieved using only a fraction of the reflected power from the 90 kW{sub t} dish concentrator. This paper discusses the solar thermophotovoltaic testbed prototype unit, test data, and presents an analysis of the unit`s performance. A combination of analytical analysis and test data is used to obtain an understanding of the system and subsystem performance. The preliminary results of these tests and analysis indicate a solar thermophotovoltaic power system can achieve high system performance. Furthermore, system demonstrations are possible utilizing a combination of current off-the-shelf hardware components and components currently being tested in laboratories. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

  14. Tower-Based Greenhouse Gas Measurement Network Design---The National Institute of Standards and Technology North East Corridor Testbed.

    Science.gov (United States)

    Lopez-Coto, Israel; Ghosh, Subhomoy; Prasad, Kuldeep; Whetstone, James

    2017-09-01

    The North-East Corridor (NEC) Testbed project is the 3rd of three NIST (National Institute of Standards and Technology) greenhouse gas emissions testbeds designed to advance greenhouse gas measurements capabilities. A design approach for a dense observing network combined with atmospheric inversion methodologies is described. The Advanced Research Weather Research and Forecasting Model with the Stochastic Time-Inverted Lagrangian Transport model were used to derive the sensitivity of hypothetical observations to surface greenhouse gas emissions (footprints). Unlike other network design algorithms, an iterative selection algorithm, based on a k -means clustering method, was applied to minimize the similarities between the temporal response of each site and maximize sensitivity to the urban emissions contribution. Once a network was selected, a synthetic inversion Bayesian Kalman filter was used to evaluate observing system performance. We present the performances of various measurement network configurations consisting of differing numbers of towers and tower locations. Results show that an overly spatially compact network has decreased spatial coverage, as the spatial information added per site is then suboptimal as to cover the largest possible area, whilst networks dispersed too broadly lose capabilities of constraining flux uncertainties. In addition, we explore the possibility of using a very high density network of lower cost and performance sensors characterized by larger uncertainties and temporal drift. Analysis convergence is faster with a large number of observing locations, reducing the response time of the filter. Larger uncertainties in the observations implies lower values of uncertainty reduction. On the other hand, the drift is a bias in nature, which is added to the observations and, therefore, biasing the retrieved fluxes.

  15. Enhanced spatial resolution on figures versus grounds.

    Science.gov (United States)

    Hecht, Lauren N; Cosman, Joshua D; Vecera, Shaun P

    2016-07-01

    Much is known about the cues that determine figure-ground assignment, but less is known about the consequences of figure-ground assignment on later visual processing. Previous work has demonstrated that regions assigned figural status are subjectively more shape-like and salient than background regions. The increase in subjective salience of figural regions could be caused by a number of processes, one of which may be enhanced perceptual processing (e.g., an enhanced neural representation) of figures relative to grounds. We explored this hypothesis by having observers perform a perceptually demanding spatial resolution task in which targets appeared on either figure or ground regions. To rule out a purely attentional account of figural salience, observers discriminated targets on the basis of a region's color (red or green), which was equally likely to define the figure or the ground. The results of our experiments showed that targets appearing on figures were discriminated more accurately than those appearing in ground regions. In addition, targets appearing on figures were discriminated better than those presented in regions considered figurally neutral, but targets appearing within ground regions were discriminated more poorly than those appearing in figurally neutral regions. Taken together, our findings suggest that when two regions share a contour, regions assigned as figure are perceptually enhanced, whereas regions assigned as ground are perceptually suppressed.

  16. Enhanced spatial resolution on figures versus grounds

    Science.gov (United States)

    Hecht, Lauren N.; Cosman, Joshua D.; Vecera, Shaun P.

    2016-01-01

    Much is known about the cues that determine figure-ground assignment, but less is known about the consequences of figure-ground assignment on later visual processing. Previous work has demonstrated that regions assigned figural status are subjectively more shape-like and salient than background regions. The increase in subjective salience of figural regions could be caused by a number of processes, one of which may be enhanced perceptual processing (e.g., an enhanced neural representation) of figures relative to grounds. We explored this hypothesis by having observers perform a perceptually demanding spatial resolution task in which targets appeared either on figure or ground regions. To rule out a purely attentional account of figural salience, observers discriminated targets on the basis of a region’s color (red or green), which was equally likely to define the figure or the ground. The results of our experiments show that targets appearing on figures were discriminated more accurately than those appearing in ground regions. In addition, targets appearing on figures were discriminated better than those presented in regions considered figurally neutral, but targets appearing within ground regions were discriminated more poorly than those appearing in figurally neutral regions. Taken together, our findings suggest that when two regions share a contour, regions assigned as figure are perceptually enhanced, whereas regions assigned as grounds are perceptually suppressed. PMID:27048441

  17. Perceptual multistability in figure-ground segregation using motion stimuli.

    Science.gov (United States)

    Gori, Simone; Giora, Enrico; Pedersini, Riccardo

    2008-11-01

    In a series of experiments using ambiguous stimuli, we investigate the effects of displaying ordered, discrete series of images on the dynamics of figure-ground segregation. For low frame presentation speeds, the series were perceived as a sequence of discontinuous, static images, while for high speeds they were perceived as continuous. We conclude that using stimuli varying continuously along one parameter results in stronger hysteresis and reduces spontaneous switching compared to matched static stimuli with discontinuous parameter changes. The additional evidence that the size of the hysteresis effects depended on trial duration is consistent with the stochastic nature of the dynamics governing figure-ground segregation. The results showed that for continuously changing stimuli, alternative figure-ground organizations are resolved via low-level, dynamical competition. A second series of experiments confirmed these results with an ambiguous stimulus based on Petter's effect.

  18. Ground-freezing experience on the east side access Northern Boulevard crossing, New York

    OpenAIRE

    Schmall, Paul; Dawson, Andrew

    2017-01-01

    A brief review is given of ground freezing technology as a means of providing groundwater cut-off and temporary structural support in weak ground for transportation tunnelling and shaft-sinking operations. Then detailed coverage of a particular case history is reported in variable soils in Queens, New York. As part of the upgrading of rail access from Long Island into Manhattan, a tunnel was required that necessitated a frozen arch structure under a ‘live’ roadway and rail lines. The installa...

  19. Use of Cultivation Data from the Algae Testbed Public Private Partnership as Utilized in NREL's Algae State of Technology Assessments

    Energy Technology Data Exchange (ETDEWEB)

    Knoshaug, Eric [National Renewable Energy Lab. (NREL), Golden, CO (United States); Laurens, Lieve [National Renewable Energy Lab. (NREL), Golden, CO (United States); Kinchin, Christopher [National Renewable Energy Lab. (NREL), Golden, CO (United States); Davis, Ryan [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-10-01

    The Algae Testbed Public Private Partnership (ATP3) conducted algal growth experiments over the course of 16 months termed the Unified Field Studies (UFS). These experiments were conducted at 5 different geographic locations in Arizona (ASU), California (CP), Florida (FA), Georgia (GT), and Hawaii (CELL). The UFS sought to evaluate different algal biomass harvesting strategies using identical ponds, media, and operational conditions through all four seasons across different geographic regions to isolate the effects on productivity attributed to locational climate and seasonal variability, overlaid by the differing harvest strategies. Set up as the baseline against which other experiments would build upon, it must be emphasized that as per the stated, approved experimental goals of the ATP3 UFS, no attempts at growth or lipid accumulation optimization were made; rather, the primary focus of the UFS work was to cultivate algal biomass under deliberate, consistent conditions, time periods, and harvesting protocols, to provide public data on year-round outdoor biomass production that could be directly compared between one site and another (with accompanying climate data for each site). Thus the resulting productivity numbers in effect represent a conservative baseline of non-optimized algal growth one may expect at these sites. Also clearly weather can vary dramatically from season to season and from year to year, and even within a given 'season' where an individual season's data was typically based on 4-6 week operating windows. Thus these numbers also only reflect a short snapshot in time, and must be interpreted carefully in projecting what may be expected over many years or decades (for example, a 30-year facility lifetime as evaluated in techno-economic models).

  20. Keeping hope possible: a grounded theory study of the hope experience of parental caregivers who have children in treatment for cancer.

    Science.gov (United States)

    Bally, Jill M G; Duggleby, Wendy; Holtslander, Lorraine; Mpofu, Christopher; Spurr, Shelley; Thomas, Roanne; Wright, Karen

    2014-01-01

    Hope has been found to support parents as they care for their child with a life-limiting or life-threatening illness. However, very little research focuses on the nursing care of parents of pediatric oncology patients, and therefore, nurses may have difficulty in understanding and supporting parental well-being. The purpose of this qualitative study was to gain an understanding of the experience of hope for parents who care for their child in treatment for cancer. Using purposive theoretical sampling, 16 parents participated in this study. Thirty-three open-ended, face-to-face interviews were conducted, and 14 parent journals were collected. Analysis of the data was conducted using Charmaz's constructivist grounded theory approach. A developing, substantive grounded theory was constructed. Parental hope was described as an essential, powerful, deliberate, life-sustaining, dynamic, cyclical process that was anchored in time; was calming and strengthening; and provided inner guidance through the challenging experience of preparing for the worst and hoping for the best. Parents' main concern was "fearing the loss of hope," which was ameliorated by the basic social process of "keeping hope possible" through accepting reality, establishing control, restructuring hope, and purposive positive thinking. Parents journeyed through numerous transitions related to the treatment of cancer that caused feelings of uncertainty, anxiety, stress, and loss of control. Hope was identified as vital to parents. To minimize these adverse experiences, nurses can support parents' ability to keep hope possible and thus to optimize their well-being by understanding, assessing, and supporting parental hope.

  1. Empowering Geoscience with Improved Data Assimilation Using the Data Assimilation Research Testbed "Manhattan" Release.

    Science.gov (United States)

    Raeder, K.; Hoar, T. J.; Anderson, J. L.; Collins, N.; Hendricks, J.; Kershaw, H.; Ha, S.; Snyder, C.; Skamarock, W. C.; Mizzi, A. P.; Liu, H.; Liu, J.; Pedatella, N. M.; Karspeck, A. R.; Karol, S. I.; Bitz, C. M.; Zhang, Y.

    2017-12-01

    The capabilities of the Data Assimilation Research Testbed (DART) at NCAR have been significantly expanded with the recent "Manhattan" release. DART is an ensemble Kalman filter based suite of tools, which enables researchers to use data assimilation (DA) without first becoming DA experts. Highlights: significant improvement in efficient ensemble DA for very large models on thousands of processors, direct read and write of model state files in parallel, more control of the DA output for finer-grained analysis, new model interfaces which are useful to a variety of geophysical researchers, new observation forward operators and the ability to use precomputed forward operators from the forecast model. The new model interfaces and example applications include the following: MPAS-A; Model for Prediction Across Scales - Atmosphere is a global, nonhydrostatic, variable-resolution mesh atmospheric model, which facilitates multi-scale analysis and forecasting. The absence of distinct subdomains eliminates problems associated with subdomain boundaries. It demonstrates the ability to consistently produce higher-quality analyses than coarse, uniform meshes do. WRF-Chem; Weather Research and Forecasting + (MOZART) Chemistry model assimilates observations from FRAPPÉ (Front Range Air Pollution and Photochemistry Experiment). WACCM-X; Whole Atmosphere Community Climate Model with thermosphere and ionosphere eXtension assimilates observations of electron density to investigate sudden stratospheric warming. CESM (weakly) coupled assimilation; NCAR's Community Earth System Model is used for assimilation of atmospheric and oceanic observations into their respective components using coupled atmosphere+land+ocean+sea+ice forecasts. CESM2.0; Assimilation in the atmospheric component (CAM, WACCM) of the newly released version is supported. This version contains new and extensively updated components and software environment. CICE; Los Alamos sea ice model (in CESM) is used to assimilate

  2. Early stages of figure-ground segregation during perception of the face-vase.

    Science.gov (United States)

    Pitts, Michael A; Martínez, Antígona; Brewer, James B; Hillyard, Steven A

    2011-04-01

    The temporal sequence of neural processes supporting figure-ground perception was investigated by recording ERPs associated with subjects' perceptions of the face-vase figure. In Experiment 1, subjects continuously reported whether they perceived the face or the vase as the foreground figure by pressing one of two buttons. Each button press triggered a probe flash to the face region, the vase region, or the borders between the two. The N170/vertex positive potential (VPP) component of the ERP elicited by probes to the face region was larger when subjects perceived the faces as figure. Preceding the N170/VPP, two additional components were identified. First, when the borders were probed, ERPs differed in amplitude as early as 110 msec after probe onset depending on subjects' figure-ground perceptions. Second, when the face or vase regions were probed, ERPs were more positive (at ∼ 150-200 msec) when that region was perceived as figure versus background. These components likely reflect an early "border ownership" stage, and a subsequent "figure-ground segregation" stage of processing. To explore the influence of attention on these stages of processing, two additional experiments were conducted. In Experiment 2, subjects selectively attended to the face or vase region, and the same early ERP components were again produced. In Experiment 3, subjects performed an identical selective attention task, but on a display lacking distinctive figure-ground borders, and neither of the early components were produced. Results from these experiments suggest sequential stages of processing underlying figure-ground perception, each which are subject to modifications by selective attention.

  3. The haptic pleasures of ground-feel: The role of textured terrain in motivating regular exercise.

    Science.gov (United States)

    Brown, Katrina M

    2017-07-01

    This paper explores the role that somatic or bodily touch-based experience of ground surface textures plays in securing a commitment to health-giving exercise practices, and argues that ground-feel is a neglected and underrated dimension of how environments co-constitute health. Past work has largely either overlooked ground-feel or positioned rough ground solely as a barrier to bodily movement. This research, however, informed by mobile and video ethnographies of walking and mountain biking in Scotland, elaborates a number of ways in which the experience of textured terrain can produce sensory and emotional experiences that motivate regular exercise. The possibility of positive tactile as well as visual experiences of landscapes, including uneven as well as smooth surfaces, ought then to be taken more seriously in designing everyday outdoor environments that encourage the energetic movement of bodies. A key challenge is to identify the optimal mix of textured and smooth ground surfaces to encourage increased energetic engagement for the widest range of users. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  4. Victimising of School Bullying: A Grounded Theory

    Science.gov (United States)

    Thornberg, Robert; Halldin, Karolina; Bolmsjo, Natalie; Petersson, Annelie

    2013-01-01

    The aim of this study was to investigate how individuals;who had been victims of school bullying; perceived their bullying experiences and how these had affected them; and to generate a grounded theory of being a victim of bullying at school. Twenty-one individuals, who all had prior experiences of being bullied in school for more than one year,…

  5. Luxury consumption of soil nutrients: a possible competitive strategy in above-ground and below-ground biomass allocation and root morphology for slow-growing arctic vegetation?

    NARCIS (Netherlands)

    Wijk, van M.T.; Williams, M.; Gough, L.; Hobbie, S.E.; Shaver, G.R.

    2003-01-01

    1 A field-experiment was used to determine how plant species might retain dominance in an arctic ecosystem receiving added nutrients. We both measured and modelled the above-ground and below-ground biomass allocation and root morphology of non-acidic tussock tundra near Toolik Lake, Alaska, after 4

  6. Multiple cues add up in defining a figure on a ground.

    Science.gov (United States)

    Devinck, Frédéric; Spillmann, Lothar

    2013-01-25

    We studied the contribution of multiple cues to figure-ground segregation. Convexity, symmetry, and top-down polarity (henceforth called wide base) were used as cues. Single-cue displays as well as ambiguous stimulus patterns containing two or three cues were presented. Error rate (defined by responses to uncued stimuli) and reaction time were used to quantify the figural strength of a given cue. In the first experiment, observers were asked to report which of two regions, left or right, appeared as foreground figure. Error rate did not benefit from adding additional cues if convexity was present, suggesting that responses were based on convexity as the predominant figural determinant. However, reaction time became shorter with additional cues even if convexity was present. For example, when symmetry and wide base were added, figure-ground segregation was facilitated. In a second experiment, stimulus patterns were exposed for 150ms to rule out eye movements. Results were similar to those found in the first experiment. Both experiments suggest that under the conditions of our experiment figure-ground segregation is perceived more readily, when several cues cooperate in defining the figure. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. GPM GROUND VALIDATION CITATION VIDEOS IPHEX V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GPM Ground Validation Citation Videos IPHEx data were collected during the Integrated Precipitation and Hydrology Experiment (IPHEx) in the Southern...

  8. Cargo container inspection test program at ARPA's Nonintrusive Inspection Technology Testbed

    Science.gov (United States)

    Volberding, Roy W.; Khan, Siraj M.

    1994-10-01

    An x-ray-based cargo inspection system test program is being conducted at the Advanced Research Project Agency (ARPA)-sponsored Nonintrusive Inspection Technology Testbed (NITT) located in the Port of Tacoma, Washington. The test program seeks to determine the performance that can be expected from a dual, high-energy x-ray cargo inspection system when inspecting ISO cargo containers. This paper describes an intensive, three-month, system test involving two independent test groups, one representing the criminal smuggling element and the other representing the law enforcement community. The first group, the `Red Team', prepares ISO containers for inspection at an off-site facility. An algorithm randomly selects and indicates the positions and preparation of cargoes within a container. The prepared container is dispatched to the NITT for inspection by the `Blue Team'. After in-gate processing, it is queued for examination. The Blue Team inspects the container and decides whether or not to pass the container. The shipment undergoes out-gate processing and returns to the Red Team. The results of the inspection are recorded for subsequent analysis. The test process, including its governing protocol, the cargoes, container preparation, the examination and results available at the time of submission are presented.

  9. HyspIRI Low Latency Concept and Benchmarks

    Science.gov (United States)

    Mandl, Dan

    2010-01-01

    Topics include HyspIRI low latency data ops concept, HyspIRI data flow, ongoing efforts, experiment with Web Coverage Processing Service (WCPS) approach to injecting new algorithms into SensorWeb, low fidelity HyspIRI IPM testbed, compute cloud testbed, open cloud testbed environment, Global Lambda Integrated Facility (GLIF) and OCC collaboration with Starlight, delay tolerant network (DTN) protocol benchmarking, and EO-1 configuration for preliminary DTN prototype.

  10. 618-10 Burial Ground Trench Remediation and 618-10 and 618-11 Burial Ground Nonintrusive Characterization of Vertical Pipe Units Lessons Learned

    Energy Technology Data Exchange (ETDEWEB)

    Darby, J. W.

    2012-06-28

    A “lessons learned” is a noteworthy practice or innovative approach that is captured and shared to promote repeat application, or an adverse work practice/experience that is captured and shared to avoid reoccurrence. This document provides the lessons learned identified by the 618-10 Burial Ground trench remediation and the 618-10 and 618-11 Burial Ground nonintrusive characterization of the vertical pipe units (VPUs).

  11. An interactive physics-based unmanned ground vehicle simulator leveraging open source gaming technology: progress in the development and application of the virtual autonomous navigation environment (VANE) desktop

    Science.gov (United States)

    Rohde, Mitchell M.; Crawford, Justin; Toschlog, Matthew; Iagnemma, Karl D.; Kewlani, Guarav; Cummins, Christopher L.; Jones, Randolph A.; Horner, David A.

    2009-05-01

    It is widely recognized that simulation is pivotal to vehicle development, whether manned or unmanned. There are few dedicated choices, however, for those wishing to perform realistic, end-to-end simulations of unmanned ground vehicles (UGVs). The Virtual Autonomous Navigation Environment (VANE), under development by US Army Engineer Research and Development Center (ERDC), provides such capabilities but utilizes a High Performance Computing (HPC) Computational Testbed (CTB) and is not intended for on-line, real-time performance. A product of the VANE HPC research is a real-time desktop simulation application under development by the authors that provides a portal into the HPC environment as well as interaction with wider-scope semi-automated force simulations (e.g. OneSAF). This VANE desktop application, dubbed the Autonomous Navigation Virtual Environment Laboratory (ANVEL), enables analysis and testing of autonomous vehicle dynamics and terrain/obstacle interaction in real-time with the capability to interact within the HPC constructive geo-environmental CTB for high fidelity sensor evaluations. ANVEL leverages rigorous physics-based vehicle and vehicle-terrain interaction models in conjunction with high-quality, multimedia visualization techniques to form an intuitive, accurate engineering tool. The system provides an adaptable and customizable simulation platform that allows developers a controlled, repeatable testbed for advanced simulations. ANVEL leverages several key technologies not common to traditional engineering simulators, including techniques from the commercial video-game industry. These enable ANVEL to run on inexpensive commercial, off-the-shelf (COTS) hardware. In this paper, the authors describe key aspects of ANVEL and its development, as well as several initial applications of the system.

  12. Availability of phosphorus from ground phosphate rocks for rape (Brassica napus L.)

    International Nuclear Information System (INIS)

    Zhu Yongyi; Yang Juncheng; Chen Jingjian; Liu Delin; Zhu Zhaomin; Wu Ming

    1996-09-01

    The availability of phosphorus from the ground phosphate rock, which is provided by Kaiyang mining plant, Guizhou Province of China, is investigated in pot experiment with acid red soil for rape (Brassica napus L. No. 13 Xingyou, Chinese Olive Group) by 32 P indirect labelling method. The results show that the yield increased significantly by applying ground phosphate rock (GPR) and the efficiency of GPR is equal to 17.1% of that from calcium superphosphate. It is calculated as that the fertilizer efficiency of 1 kg of calcium superphosphate is the same as that of 8.53 kg ground phosphate rock in Guizhou Province of China. The effect on the grain yield is evaluated by pot and field microplot experiments, and it is found that the main effect is to increase the pod number. The fertilizer efficiency in field experiment is the same as that in pot experiment. (9 refs., 1 fig., 7 tabs.)

  13. Ground-Laboratory to In-Space Atomic Oxygen Correlation for the PEACE Polymers

    Science.gov (United States)

    Stambler, Arielle H.; Inoshita, Karen E.; Roberts, Lily M.; Barbagallo, Claire E.; de Groh, Kim K.; Banks, Bruce A.

    2009-01-01

    The Materials International Space Station Experiment 2 (MISSE 2) Polymer Erosion and Contamination Experiment (PEACE) polymers were exposed to the environment of low Earth orbit (LEO) for 3.95 years from 2001 to 2005. There were forty-one different PEACE polymers, which were flown on the exterior of the International Space Station (ISS) in order to determine their atomic oxygen erosion yields. In LEO, atomic oxygen is an environmental durability threat, particularly for long duration mission exposures. Although space flight experiments, such as the MISSE 2 PEACE experiment, are ideal for determining LEO environmental durability of spacecraft materials, ground-laboratory testing is often relied upon for durability evaluation and prediction. Unfortunately, significant differences exist between LEO atomic oxygen exposure and atomic oxygen exposure in ground-laboratory facilities. These differences include variations in species, energies, thermal exposures and radiation exposures, all of which may result in different reactions and erosion rates. In an effort to improve the accuracy of ground-based durability testing, ground-laboratory to in-space atomic oxygen correlation experiments have been conducted. In these tests, the atomic oxygen erosion yields of the PEACE polymers were determined relative to Kapton H using a radio-frequency (RF) plasma asher (operated on air). The asher erosion yields were compared to the MISSE 2 PEACE erosion yields to determine the correlation between erosion rates in the two environments. This paper provides a summary of the MISSE 2 PEACE experiment; it reviews the specific polymers tested as well as the techniques used to determine erosion yield in the asher, and it provides a correlation between the space and ground-laboratory erosion yield values. Using the PEACE polymers' asher to in-space erosion yield ratios will allow more accurate in-space materials performance predictions to be made based on plasma asher durability evaluation.

  14. Phase Retrieval Using a Genetic Algorithm on the Systematic Image-Based Optical Alignment Testbed

    Science.gov (United States)

    Taylor, Jaime R.

    2003-01-01

    NASA s Marshall Space Flight Center s Systematic Image-Based Optical Alignment (SIBOA) Testbed was developed to test phase retrieval algorithms and hardware techniques. Individuals working with the facility developed the idea of implementing phase retrieval by breaking the determination of the tip/tilt of each mirror apart from the piston motion (or translation) of each mirror. Presented in this report is an algorithm that determines the optimal phase correction associated only with the piston motion of the mirrors. A description of the Phase Retrieval problem is first presented. The Systematic Image-Based Optical Alignment (SIBOA) Testbeb is then described. A Discrete Fourier Transform (DFT) is necessary to transfer the incoming wavefront (or estimate of phase error) into the spatial frequency domain to compare it with the image. A method for reducing the DFT to seven scalar/matrix multiplications is presented. A genetic algorithm is then used to search for the phase error. The results of this new algorithm on a test problem are presented.

  15. Ancient tombs in China and shallow ground burial of solid low-intermediate level radioactive wastes

    International Nuclear Information System (INIS)

    Huang Yawen; Gu Cunli

    1987-01-01

    Having reviewed the experiences with ancient tombs in China, particularly the experiences with tomb siting, configuration of tombs, backfilling materials, civil engineering techniques, sealing techniques, drainage system, antiseptic techniques, a comparison between the ancient tombs and the shallow ground burial of solid radioactive wastes is made. The authors believe that the brilliant achievements of ancient tombs in China in keeping ancient corpses and funeral objects are a historical evidence for safety of shallow ground burial of radioactive wastes, and that the main experiences with the ancient tombs may be useful to shallow ground burial of solid radioactive wastes

  16. Early Stages of Figure–Ground Segregation during Perception of the Face–Vase

    Science.gov (United States)

    Pitts, Michael A.; Martínez, Antígona; Brewer, James B.; Hillyard, Steven A.

    2011-01-01

    The temporal sequence of neural processes supporting figure–ground perception was investigated by recording ERPs associated with subjects’ perceptions of the face–vase figure. In Experiment 1, subjects continuously reported whether they perceived the face or the vase as the foreground figure by pressing one of two buttons. Each button press triggered a probe flash to the face region, the vase region, or the borders between the two. The N170/vertex positive potential (VPP) component of the ERP elicited by probes to the face region was larger when subjects perceived the faces as figure. Preceding the N170/VPP, two additional components were identified. First, when the borders were probed, ERPs differed in amplitude as early as 110 msec after probe onset depending on subjects’ figure–ground perceptions. Second, when the face or vase regions were probed, ERPs were more positive (at ~150–200 msec) when that region was perceived as figure versus background. These components likely reflect an early “border ownership” stage, and a subsequent “figure–ground segregation” stage of processing. To explore the influence of attention on these stages of processing, two additional experiments were conducted. In Experiment 2, subjects selectively attended to the face or vase region, and the same early ERP components were again produced. In Experiment 3, subjects performed an identical selective attention task, but on a display lacking distinctive figure–ground borders, and neither of the early components were produced. Results from these experiments suggest sequential stages of processing underlying figure–ground perception, each which are subject to modifications by selective attention. PMID:20146604

  17. Nuclear quadrupole moment of the 99Tc ground state

    International Nuclear Information System (INIS)

    Errico, Leonardo; Darriba, German; Renteria, Mario; Tang Zhengning; Emmerich, Heike; Cottenier, Stefaan

    2008-01-01

    By combining first-principles calculations and existing nuclear magnetic resonance (NMR) experiments, we determine the quadrupole moment of the 9/2 + ground state of 99 Tc to be (-)0.14(3)b. This confirms the value of -0.129(20)b, which is currently believed to be the most reliable experimental determination, and disagrees with two earlier experimental values. We supply ab initio calculated electric-field gradients for Tc in YTc 2 and ZrTc 2 . If this calculated information would be combined with yet to be performed Tc-NMR experiments in these compounds, the error bar on the 99 Tc ground state quadrupole moment could be further reduced

  18. Dynasting Theory: Lessons in learning grounded theory

    Directory of Open Access Journals (Sweden)

    Johnben Teik-Cheok Loy, MBA, MTS, Ph.D.

    2011-06-01

    Full Text Available This article captures the key learning lessons gleaned from the author’s experience learning and developing a grounded theory for his doctoral dissertation using the classic methodology as conceived by Barney Glaser. The theory was developed through data gathered on founders and successors of Malaysian Chinese family-own businesses. The main concern for Malaysian Chinese family businesses emerged as dynasting . the building, maintaining, and growing the power and resources of the business within the family lineage. The core category emerged as dynasting across cultures, where founders and successors struggle to transition from traditional Chinese to hybrid cultural and modernized forms of family business from one generation to the next. The key learning lessons were categorized under five headings: (a sorting through different versions of grounded theory, (b educating and managing research stakeholders, (c embracing experiential learning, (d discovering the core category: grounded intuition, and (e recognizing limitations and possibilities.Keywords: grounded theory, learning, dynasting, family business, Chinese

  19. A fiber Bragg grating acceleration sensor for ground surveillance

    Science.gov (United States)

    Jiang, Shaodong; Zhang, Faxiang; Lv, Jingsheng; Ni, Jiasheng; Wang, Chang

    2017-10-01

    Ground surveillance system is a kind of intelligent monitoring equipment for detecting and tracking the ground target. This paper presents a fiber Bragg grating (FBG) acceleration sensor for ground surveillance, which has the characteristics of no power supply, anti-electromagnetic interference, easy large-scale networking, and small size. Which make it able to achieve the advantage of the ground surveillance system while avoiding the shortcoming of the electric sensing. The sensor has a double cantilever beam structure with a sensitivity of 1000 pm/g. Field experiment has been carried out on a flood beach to examine the sensor performance. The result shows that the detection distance on the walking of personnel reaches 70m, and the detection distance on the ordinary motor vehicle reaches 200m. The performance of the FBG sensor can satisfy the actual needs of the ground surveillance system.

  20. The CELSS Antarctic Analog Project: An Advanced Life Support Testbed at the Amundsen-Scott South Pole Station, Antarctica

    Science.gov (United States)

    Straight, Christian L.; Bubenheim, David L.; Bates, Maynard E.; Flynn, Michael T.

    1994-01-01

    CELSS Antarctic Analog Project (CAAP) represents a logical solution to the multiple objectives of both the NASA and the National Science Foundation (NSF). CAAP will result in direct transfer of proven technologies and systems, proven under the most rigorous of conditions, to the NSF and to society at large. This project goes beyond, as it must, the generally accepted scope of CELSS and life support systems including the issues of power generation, human dynamics, community systems, and training. CAAP provides a vivid and starkly realistic testbed of Controlled Ecological Life Support System (CELSS) and life support systems and methods. CAAP will also be critical in the development and validation of performance parameters for future advanced life support systems.

  1. Communication grounding facility

    International Nuclear Information System (INIS)

    Lee, Gye Seong

    1998-06-01

    It is about communication grounding facility, which is made up twelve chapters. It includes general grounding with purpose, materials thermal insulating material, construction of grounding, super strength grounding method, grounding facility with grounding way and building of insulating, switched grounding with No. 1A and LCR, grounding facility of transmission line, wireless facility grounding, grounding facility in wireless base station, grounding of power facility, grounding low-tenton interior power wire, communication facility of railroad, install of arrester in apartment and house, install of arrester on introduction and earth conductivity and measurement with introduction and grounding resistance.

  2. The ground support computer and in-orbit survey data analysis program for the SEEP experiment

    International Nuclear Information System (INIS)

    Voss, H.D.; Datlowe, D.W.; Mobilia, J.; Roselle, S.N.

    1985-01-01

    The ground support computer equipment (GSE) and production survey plot and analysis software are described for the Stimulated Emissions of Energetic Particles (SEEP) experiment on the S81-1 satellite. A general purpose satellite data acquisition circuit was developed based on a Z-80 portable microcomputer. By simply changing instrument control software and electrical connectors, automatic testing and control of the various SEEP instruments was accomplished. A new feature incorporated into the SEEP data analysis phase was the development of a correlative data base for all of the SEEP instruments. A CPU efficient survey plot program (with ephemeris) was developed to display the approximate 3100 hours of data, with a time resolution of 0.5 sec, from the ten instrument sensors. The details of the general purpose multigraph algorithms and plot formats are presented. For the first time new associations are being investigated of simultaneous particle, X-ray, optical and plasma density satellite measurements

  3. A grounded theory study of 'turning into a strong nurse': Earthquake experiences and perspectives on disaster nursing education.

    Science.gov (United States)

    Li, Yan; Turale, Sue; Stone, Teresa E; Petrini, Marcia

    2015-09-01

    While Asia has the dubious distinction of being the world's most natural disaster-prone area, disaster nursing education and training are sparse in many Asian countries, especially China where this study took place. To explore the earthquake disaster experiences of Chinese nurses and develop a substantive theory of earthquake disaster nursing that will help inform future development of disaster nursing education. A qualitative study employing grounded theory, informed by symbolic interactionism. Fifteen Chinese registered nurses from five hospitals in Jiangxi Province who undertook relief efforts after the 2008 Wenchuan Earthquake. Data were collected in 2012-2013 in digitally-recorded, semi-structured, in-depth interviews and reflective field notes, and analyzed using Glaser's grounded theory method. Participants were unprepared educationally and psychologically for their disaster work. Supporting the emergent theory of "working in that terrible environment", was the core category of "turning into a strong nurse", a process of three stages: "going to the disaster"; "immersing in the disaster"; and "trying to let disaster experiences fade away". The participants found themselves thrust in "terrible" scenes of destruction, experienced personal dangers and ethical dilemmas, and tried the best they could to help survivors, communities and themselves, with limited resources and confronting professional work. Our rich findings confirm those of other studies in China and elsewhere, that attention must be paid to disaster education and training for nurses, as well as the mental health of nurses who work in disaster areas. Emergent theory helps to inform nurse educators, researchers, leaders and policy makers in China, and elsewhere in developing strategies to better prepare nurses for future disasters, and assist communities to prepare for and recover after earthquake disasters. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Figure-ground segregation can rely on differences in motion direction.

    Science.gov (United States)

    Kandil, Farid I; Fahle, Manfred

    2004-12-01

    If the elements within a figure move synchronously while those in the surround move at a different time, the figure is easily segregated from the surround and thus perceived. Lee and Blake (1999) [Visual form created solely from temporal structure. Science, 284, 1165-1168] demonstrated that this figure-ground separation may be based not only on time differences between motion onsets, but also on the differences between reversals of motion direction. However, Farid and Adelson (2001) [Synchrony does not promote grouping in temporally structured displays. Nature Neuroscience, 4, 875-876] argued that figure-ground segregation in the motion-reversal experiment might have been based on a contrast artefact and concluded that (a)synchrony as such was 'not responsible for the perception of form in these or earlier displays'. Here, we present experiments that avoid contrast artefacts but still produce figure-ground segregation based on purely temporal cues. Our results show that subjects can segregate figure from ground even though being unable to use motion reversals as such. Subjects detect the figure when either (i) motion stops (leading to contrast artefacts), or (ii) motion directions differ between figure and ground. Segregation requires minimum delays of about 15 ms. We argue that whatever the underlying cues and mechanisms, a second stage beyond motion detection is required to globally compare the outputs of local motion detectors and to segregate figure from ground. Since analogous changes take place in both figure and ground in rapid succession, this second stage has to detect the asynchrony with high temporal precision.

  5. Crawl space assisted heat pump. [using stored ground heat

    Science.gov (United States)

    Ternes, M. P.

    1980-01-01

    A variety of experiments and simulations, currently being designed or underway, to determine the feasibility of conditioning the source air of an air to air heat pump using stored ground heat or cool to produce higher seasonal COP's and net energy savings are discussed. The ground would condition ambient air as it is drawn through the crawl space of a house. Tests designed to evaluate the feasibility of the concept, to determine the amount of heat or cool available from the ground, to study the effect of the system on the heating and cooling loads of the house, to study possible mechanisms which could enhance heat flow through the ground, and to determine if diurnal temperature swings are necessary to achieve successful system performance are described.

  6. Grounding word learning in space.

    Directory of Open Access Journals (Sweden)

    Larissa K Samuelson

    Full Text Available Humans and objects, and thus social interactions about objects, exist within space. Words direct listeners' attention to specific regions of space. Thus, a strong correspondence exists between where one looks, one's bodily orientation, and what one sees. This leads to further correspondence with what one remembers. Here, we present data suggesting that children use associations between space and objects and space and words to link words and objects--space binds labels to their referents. We tested this claim in four experiments, showing that the spatial consistency of where objects are presented affects children's word learning. Next, we demonstrate that a process model that grounds word learning in the known neural dynamics of spatial attention, spatial memory, and associative learning can capture the suite of results reported here. This model also predicts that space is special, a prediction supported in a fifth experiment that shows children do not use color as a cue to bind words and objects. In a final experiment, we ask whether spatial consistency affects word learning in naturalistic word learning contexts. Children of parents who spontaneously keep objects in a consistent spatial location during naming interactions learn words more effectively. Together, the model and data show that space is a powerful tool that can effectively ground word learning in social contexts.

  7. Figure/Ground Segmentation via a Haptic Glance: Attributing Initial Finger Contacts to Objects or Their Supporting Surfaces.

    Science.gov (United States)

    Pawluk, D; Kitada, R; Abramowicz, A; Hamilton, C; Lederman, S J

    2011-01-01

    The current study addresses the well-known "figure/ground" problem in human perception, a fundamental topic that has received surprisingly little attention from touch scientists to date. Our approach is grounded in, and directly guided by, current knowledge concerning the nature of haptic processing. Given inherent figure/ground ambiguity in natural scenes and limited sensory inputs from first contact (a "haptic glance"), we consider first whether people are even capable of differentiating figure from ground (Experiments 1 and 2). Participants were required to estimate the strength of their subjective impression that they were feeling an object (i.e., figure) as opposed to just the supporting structure (i.e., ground). Second, we propose a tripartite factor classification scheme to further assess the influence of kinetic, geometric (Experiments 1 and 2), and material (Experiment 2) factors on haptic figure/ground segmentation, complemented by more open-ended subjective responses obtained at the end of the experiment. Collectively, the results indicate that under certain conditions it is possible to segment figure from ground via a single haptic glance with a reasonable degree of certainty, and that all three factor classes influence the estimated likelihood that brief, spatially distributed fingertip contacts represent contact with an object and/or its background supporting structure.

  8. Launch and Landing Effects Ground Operations (LLEGO) Model

    Science.gov (United States)

    2008-01-01

    LLEGO is a model for understanding recurring launch and landing operations costs at Kennedy Space Center for human space flight. Launch and landing operations are often referred to as ground processing, or ground operations. Currently, this function is specific to the ground operations for the Space Shuttle Space Transportation System within the Space Shuttle Program. The Constellation system to follow the Space Shuttle consists of the crewed Orion spacecraft atop an Ares I launch vehicle and the uncrewed Ares V cargo launch vehicle. The Constellation flight and ground systems build upon many elements of the existing Shuttle flight and ground hardware, as well as upon existing organizations and processes. In turn, the LLEGO model builds upon past ground operations research, modeling, data, and experience in estimating for future programs. Rather than to simply provide estimates, the LLEGO model s main purpose is to improve expenses by relating complex relationships among functions (ground operations contractor, subcontractors, civil service technical, center management, operations, etc.) to tangible drivers. Drivers include flight system complexity and reliability, as well as operations and supply chain management processes and technology. Together these factors define the operability and potential improvements for any future system, from the most direct to the least direct expenses.

  9. GPM GROUND VALIDATION KCBW NEXRAD GCPEX V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GPM Ground Validation KCBW NEXRAD GCPEx dataset was collected during January 9, 2012 to March 12, 2012 for the GPM Cold-season Precipitation Experiment (GCPEx)....

  10. Linking the Intercultural and Grounded Theory: Methodological Issues in Migration Research

    Directory of Open Access Journals (Sweden)

    Vera Sheridan

    2009-01-01

    Full Text Available Connecting intercultural research with Grounded Theory was advocated in the early history of intercultural theorising and includes the development of researchers' intercultural competencies. Such competency comes to the fore where intercultural theory places an equal emphasis on home and host cultures in migration research. In this context we have found a Grounded Theory approach particularly suitable for disentangling complex interlinkings within migration experiences and their individual outcomes. Grounded Theory allows for the exploration of various theories in different fields and the emergence of new or deeper interpretations of intercultural experiences, including where research has not engaged deeply with or avoided intercultural contexts. The use of software, based on Grounded Theory, provides the resource for systematically exploring the inter-related nature of data. In addition, engaging in intercultural research, in particular, raises questions around our practice as social science researchers: adherence to ethics guidelines, for instance, can be in some conflict with the relations we build with members of communities whose cultural values, for instance around friendship or trust, impact on the norms of both our own and institutional expectations. This leads to reflection on the relationship with research participants in terms of our own intercultural experiences and position. URN: urn:nbn:de:0114-fqs0901363

  11. Ground Pollution Science

    International Nuclear Information System (INIS)

    Oh, Jong Min; Bae, Jae Geun

    1997-08-01

    This book deals with ground pollution science and soil science, classification of soil and fundamentals, ground pollution and human, ground pollution and organic matter, ground pollution and city environment, environmental problems of the earth and ground pollution, soil pollution and development of geological features of the ground, ground pollution and landfill of waste, case of measurement of ground pollution.

  12. Report of Earthquake Drills with Experiences of Ground Motion in Childcare for Young Children, Japan

    Science.gov (United States)

    Yamada, N.

    2013-12-01

    After the Great East Japan Earthquake of 2011, this disaster has become one of the opportunities to raise awareness of earthquake and tsunami disaster prevention, and the improvement of disaster prevention education is to be emphasized. The influences of these bring the extension to the spatial axis in Japan, and also, it is important to make a development of the education with continuous to the expansion of time axes. Although fire or earthquake drills as the disaster prevention education are often found in Japan, the children and teachers only go from school building to outside. Besides, only the shortness of the time to spend for the drill often attracts attention. The complementary practice education by the cooperation with experts such as the firefighting is practiced, but the verification of the effects is not enough, and it is the present conditions that do not advance to the study either. Although it is expected that improvement and development of the disaster prevention educations are accomplished in future, there are a lot of the problems. Our target is construction and utilization of material contributing to the education about "During the strong motion" in case of the earthquake which may experience even if wherever of Japan. One of the our productions is the handicraft shaking table to utilize as teaching tools of the education to protect the body which is not hurt at the time of strong motion. This made much of simplicity than high reproduction of the earthquake ground motions. We aimed to helping the disaster prevention education including not only the education for young children but also for the school staff and their parents. In this report, the focusing on a way of the non-injured during the time of the earthquake ground motion, and adopting activity of the play, we are going to show the example of the framework of earthquake disaster prevention childcare through the virtual experience. This presentation has a discussion as a practice study with

  13. Earthbound Unmanned Autonomous Vehicles (UAVS) As Planetary Science Testbeds

    Science.gov (United States)

    Pieri, D. C.; Bland, G.; Diaz, J. A.; Fladeland, M. M.

    2014-12-01

    Recent advances in the technology of unmanned vehicles have greatly expanded the range of contemplated terrestrial operational environments for their use, including aerial, surface, and submarine. The advances have been most pronounced in the areas of autonomy, miniaturization, durability, standardization, and ease of operation, most notably (especially in the popular press) for airborne vehicles. Of course, for a wide range of planetary venues, autonomy at high cost of both money and risk, has always been a requirement. Most recently, missions to Mars have also featured an unprecedented degree of mobility. Combining the traditional planetary surface deployment operational and science imperatives with emerging, very accessible, and relatively economical small UAV platforms on Earth can provide flexible, rugged, self-directed, test-bed platforms for landed instruments and strategies that will ultimately be directed elsewhere, and, in the process, provide valuable earth science data. While the most direct transfer of technology from terrestrial to planetary venues is perhaps for bodies with atmospheres (and oceans), with appropriate technology and strategy accommodations, single and networked UAVs can be designed to operate on even airless bodies, under a variety of gravities. In this presentation, we present and use results and lessons learned from our recent earth-bound UAV volcano deployments, as well as our future plans for such, to conceptualize a range of planetary and small-body missions. We gratefully acknowledge the assistance of students and colleagues at our home institutions, and the government of Costa Rica, without which our UAV deployments would not have been possible. This work was carried out, in part, at the Jet Propulsion Laboratory of the California Institute of Technology under contract to NASA.

  14. Aerosol and Cloud Properties during the Cloud Cheju ABC Plume -Asian Monsoon Experiment (CAPMEX) 2008: Linking between Ground-based and UAV Measurements

    Science.gov (United States)

    Kim, S.; Yoon, S.; Venkata Ramana, M.; Ramanathan, V.; Nguyen, H.; Park, S.; Kim, M.

    2009-12-01

    Cheju Atmospheric Brown Cloud (ABC) Plume-Monsoon Experiment (CAPMEX), comprehsensive ground-based measurements and a series of data-gathering flights by specially equipped autonomous unmanned aerial vehicles (AUAVs) for aerosol and cloud, had conducted at Jeju (formerly, Cheju), South Korea during August-September 2008, to improve our understanding of how the reduction of anthropogenic emissions in China (so-called “great shutdown” ) during and after the Summer Beijing Olympic Games 2008 effcts on the air quliaty and radiation budgets and how atmospheric brown clouds (ABCs) influences solar radiation budget off Asian continent. Large numbers of in-situ and remote sensing instruments at the Gosan ABC observatory and miniaturized instruments on the aircraft measure a range of properties such as the quantity of soot, size-segregated aerosol particle numbers, total particle numbers, size-segregated cloud droplet numbers (only AUAV), aerosol scattering properties (only ground), aerosol vertical distribution, column-integrated aerosol properties, and meteorological variables. By integrating ground-level and high-elevation AUAV measurements with NASA-satellite observations (e.g., MODIS, CALIPSO), we investigate the long range transport of aerosols, the impact of ABCs on clouds, and the role of biogenic and anthropogenic aerosols on cloud condensation nuclei (CCN). In this talk, we will present the results from CAPMEX focusing on: (1) the characteristics of aerosol optical, physical and chemical properties at Gosan observatory, (2) aerosol solar heating calculated from the ground-based micro-pulse lidar and AERONET sun/sky radiometer synergy, and comparison with direct measurements from UAV, and (3) aerosol-cloud interactions in conjunction with measurements by satellites and Gosan observatory.

  15. Building a visionary astrophysics program from the ground up

    Science.gov (United States)

    Mathews, Geoffrey S.; Barnes, Joshua Edward; Coleman, Paul; Gal, Roy R.; Meech, Karen J.; Mendez, Roberto Hugo; Nassir, Michael A.; Sanders, David B.

    2015-08-01

    The University of Hawaii’s Institute for Astronomy is in the process of implementing a new Bachelor of Science in Astrophysics at UH Manoa. This requires a significant adjustment in the role of the IfA, which has long been at the forefront of modern astronomy in Hawaii and is now broadening its educational mission. The IfA’s history of excellence in research and access to observational resources are expected to draw students from around the nation and the world. These factors have inspired our programmatic focus culminating in a senior year research experience. We expect that the program will produce many undergraduate astrophysics majors, making it an ideal testbed to apply modern theories of learning to the teaching of astrophysics. We have explicitly designed the major around three pillars: physical theory, the application of physics to astrophysical phenomena, and the development of core observational astronomy skills. We describe our cooperative approach to developing a program-level curriculum map of key concepts and skills, as well as descriptors of student success throughout the program. These are central tools for course design, program assessment, and professional development.

  16. Modeled ground water age distributions

    Science.gov (United States)

    Woolfenden, Linda R.; Ginn, Timothy R.

    2009-01-01

    The age of ground water in any given sample is a distributed quantity representing distributed provenance (in space and time) of the water. Conventional analysis of tracers such as unstable isotopes or anthropogenic chemical species gives discrete or binary measures of the presence of water of a given age. Modeled ground water age distributions provide a continuous measure of contributions from different recharge sources to aquifers. A numerical solution of the ground water age equation of Ginn (1999) was tested both on a hypothetical simplified one-dimensional flow system and under real world conditions. Results from these simulations yield the first continuous distributions of ground water age using this model. Complete age distributions as a function of one and two space dimensions were obtained from both numerical experiments. Simulations in the test problem produced mean ages that were consistent with the expected value at the end of the model domain for all dispersivity values tested, although the mean ages for the two highest dispersivity values deviated slightly from the expected value. Mean ages in the dispersionless case also were consistent with the expected mean ages throughout the physical model domain. Simulations under real world conditions for three dispersivity values resulted in decreasing mean age with increasing dispersivity. This likely is a consequence of an edge effect. However, simulations for all three dispersivity values tested were mass balanced and stable demonstrating that the solution of the ground water age equation can provide estimates of water mass density distributions over age under real world conditions.

  17. Commissioning the CERN IT Agile Infrastructure with experiment workloads

    CERN Document Server

    Medrano Llamas, Ramón; Kucharczyk, Katarzyna; Denis, Marek Kamil; Cinquilli, Mattia

    2014-01-01

    In order to ease the management of their infrastructure, most of the WLCG sites are adopting cloud based strategies. In the case of CERN, the Tier 0 of the WLCG, is completely restructuring the resource and configuration management of their computing center under the codename Agile Infrastructure. Its goal is to manage 15,000 Virtual Machines by means of an OpenStack middleware in order to unify all the resources in CERN's two datacenters: the one placed in Meyrin and the new on in Wigner, Hungary. During the commissioning of this infrastructure, CERN IT is offering an attractive amount of computing resources to the experiments (800 cores for ATLAS and CMS) through a private cloud interface. ATLAS and CMS have joined forces to exploit them by running stress tests and simulation workloads since November 2012. This work will describe the experience of the first deployments of the current experiment workloads on the CERN private cloud testbed. The paper is organized as follows: the first section will explain th...

  18. Dynamic Design of Ground Transport With the Help of Computational Experiment

    Directory of Open Access Journals (Sweden)

    Kravets Victor

    2015-05-01

    Full Text Available Objectives of ground transport (motor transport vehicle have been considered. Mathematical model of nonlinear dynamics in spatial motion of asymmetric carriage in the form of Euler-Lagrange equations represented as symmetrical block structure in quaternion matrices has been developed. Kinematic equations and partition matrices of external action in which Rodrigues-Hamilton parameters have been applied describe quaternionic matrices.

  19. "Like a trip to McDonalds": a grounded theory study of patient experiences of day surgery.

    Science.gov (United States)

    Mottram, Anne

    2011-02-01

    The amount and complexity of (ambulatory) day surgery is rapidly expanding internationally. Nurses have a responsibility to provide quality care for day surgery patients. To do this they must understand all aspects of the patient experience. There is dearth of research into day surgery using a sociological frame of reference. The study investigated patients' experiences of day surgery using a sociological frame of reference. A qualitative study using the grounded theory approach was used. The study was based in two day surgery units in two urban public hospitals in the United Kingdom. 145 patients aged 18-70 years and 100 carers were purposely selected from the orthopaedic, ear nose and throat and general surgical lists. They were all English speaking and were of varied socio-economic background. The data was collected from 2004 to 2006. Semi-structured interviews were conducted on three occasions: before surgery, 48 h following surgery and one month following discharge. Permission was received from the Local Research Ethics Committee. Analysis of the data involved line-by-line analysis, compilation of key words and phrases (codes) and constant comparison of the codes until categories emerged. Patients liked day surgery and placed it within the wider societal context of efficiency and speed. Time was a major issue for them. They wished surgery, like all other aspects of their life to be a speedy process. They likened it to a McDonald's experience with its emphasis on speed, predictability and control. This study throws new light on patient experiences and offers an understanding of day surgery against a western culture which emphasises the importance of speed and efficiency. It is a popular choice for patients but at times it can be seen to be a mechanistic way of providing care. The implications for nurses to provide education and information to add to the quality of the patient experience are discussed. Copyright © 2010 Elsevier Ltd. All rights reserved.

  20. Wind power integration in island-based smart grid projects : A comparative study between Jeju Smart Grid Test-bed and Smart Grid Gotland

    OpenAIRE

    Piehl, Hampus

    2014-01-01

    Smart grids seem to be the solution to use energy from renewable and intermittent energy sources in an efficient manner. There are many research projects around the world and two of them are Jeju Smart Grid Test-bed and Smart Grid Gotland. They have in common that they are both island-based projects and connected to the Powergrid on the mainland by HVDC-link. The purpose of this thesis is to compare the two projects and find out what challenges and strategies they have related to wind power i...

  1. Damage Stability Assessment of an HSC after Grounding

    DEFF Research Database (Denmark)

    Ravn, Erik Sonne; Simonsen, Bo Cerup; Baatrup, Jan

    2000-01-01

    Currently a substantial effort is done within the International Maritime Organisation (IMO) on revision of the High Speed Craft (HSC) Code. A main issue is the extent of bottom damage and raking damage due to grounding on hard rocks and the corresponding requirements to the damage stability...... of the vessel. It has been found that high-speed craft can experience a damage length up to 100% of the ship length. It has, however, also been argued that the damage stability requirements should reflect the size and probability of the damage with a reduction of the demand for the largest damages.......In the present paper a detailed grounding and damage stability analysis is carried out for two specific HSC, a mono-hull (86 m) and a catamaran (69 m). First various grounding scenarios are considered with different values of the forward speed and ground geometry. The results indicate that 100% bottom damage...

  2. GEO light imaging national testbed (GLINT) heliostat design and testing status

    Science.gov (United States)

    Thornton, Marcia A.; Oldenettel, Jerry R.; Hult, Dane W.; Koski, Katrina; Depue, Tracy; Cuellar, Edward L.; Balfour, Jim; Roof, Morey; Yarger, Fred W.; Newlin, Greg; Ramzel, Lee; Buchanan, Peter; Mariam, Fesseha G.; Scotese, Lee

    2002-01-01

    The GEO Light Imaging National Testbed (GLINT) will use three laser beams producing simultaneous interference fringes to illuminate satellites in geosynchronous earth orbit (GEO). The reflected returns will be recorded using a large 4,000 m2 'light bucket' receiver. This imaging methodology is termed Fourier Telescopy. A major component of the 'light bucket' will be an array of 40 - 80 heliostats. Each heliostat will have a mirrored surface area of 100 m2 mounted on a rigid truss structure which is supported by an A-frame. The truss structure attaches to the torque tube elevation drive and the A-frame structure rests on an azimuth ring that could provide nearly full coverage of the sky. The heliostat is designed to operate in 15 mph winds with jitter of less than 500 microradians peak-to- peak. One objective of the design was to minimize receiver cost to the maximum extent possible while maintaining GLINT system performance specifications. The mechanical structure weights approximately seven tons and is a simple fabricated steel framework. A prototype heliostat has been assembled at Stallion Range Center, White Sands Missile Range, New Mexico and is being tested under a variety of weather and operational conditions. The preliminary results of that testing will be presented as well as some finite element model analyses that were performed to predict the performance of the structure.

  3. The ShakeOut earthquake source and ground motion simulations

    Science.gov (United States)

    Graves, R.W.; Houston, Douglas B.; Hudnut, K.W.

    2011-01-01

    The ShakeOut Scenario is premised upon the detailed description of a hypothetical Mw 7.8 earthquake on the southern San Andreas Fault and the associated simulated ground motions. The main features of the scenario, such as its endpoints, magnitude, and gross slip distribution, were defined through expert opinion and incorporated information from many previous studies. Slip at smaller length scales, rupture speed, and rise time were constrained using empirical relationships and experience gained from previous strong-motion modeling. Using this rupture description and a 3-D model of the crust, broadband ground motions were computed over a large region of Southern California. The largest simulated peak ground acceleration (PGA) and peak ground velocity (PGV) generally range from 0.5 to 1.0 g and 100 to 250 cm/s, respectively, with the waveforms exhibiting strong directivity and basin effects. Use of a slip-predictable model results in a high static stress drop event and produces ground motions somewhat higher than median level predictions from NGA ground motion prediction equations (GMPEs).

  4. Facility for the evaluation of space communications and related systems

    Science.gov (United States)

    Kerczewski, Robert J.; Svoboda, James S.; Kachmar, Brian A.

    1995-01-01

    NASA Lewis Research Center's Communications Projects Branch has developed a facility for the evaluation of space communications systems and related types of systems, called the Advanced Space Communications (ASC) Laboratory. The ASC Lab includes instrumentation, testbed hardware, and experiment control and monitor software for the evaluation of components, subsystems, systems, and networks. The ASC lab has capabilities to perform radiofrequency (RF), microwave, and millimeter-wave characterizations as well as measurements using low, medium, or high data rate digital signals. In addition to laboratory measurements, the ASC Lab also includes integrated satellite ground terminals allowing experimentation and measurements accessing operational satellites through real space links.

  5. Purely temporal figure-ground segregation.

    Science.gov (United States)

    Kandil, F I; Fahle, M

    2001-05-01

    Visual figure-ground segregation is achieved by exploiting differences in features such as luminance, colour, motion or presentation time between a figure and its surround. Here we determine the shortest delay times required for figure-ground segregation based on purely temporal features. Previous studies usually employed stimulus onset asynchronies between figure- and ground-containing possible artefacts based on apparent motion cues or on luminance differences. Our stimuli systematically avoid these artefacts by constantly showing 20 x 20 'colons' that flip by 90 degrees around their midpoints at constant time intervals. Colons constituting the background flip in-phase whereas those constituting the target flip with a phase delay. We tested the impact of frequency modulation and phase reduction on target detection. Younger subjects performed well above chance even at temporal delays as short as 13 ms, whilst older subjects required up to three times longer delays in some conditions. Figure-ground segregation can rely on purely temporal delays down to around 10 ms even in the absence of luminance and motion artefacts, indicating a temporal precision of cortical information processing almost an order of magnitude lower than the one required for some models of feature binding in the visual cortex [e.g. Singer, W. (1999), Curr. Opin. Neurobiol., 9, 189-194]. Hence, in our experiment, observers are unable to use temporal stimulus features with the precision required for these models.

  6. Development of a Ground Water Data Portal for Interoperable Data Exchange within the U.S. National Ground Water Monitoring Network and Beyond

    Science.gov (United States)

    Booth, N. L.; Brodaric, B.; Lucido, J. M.; Kuo, I.; Boisvert, E.; Cunningham, W. L.

    2011-12-01

    The need for a national groundwater monitoring network within the United States is profound and has been recognized by organizations outside government as a major data gap for managing ground-water resources. Our country's communities, industries, agriculture, energy production and critical ecosystems rely on water being available in adequate quantity and suitable quality. To meet this need the Subcommittee on Ground Water, established by the Federal Advisory Committee on Water Information, created a National Ground Water Monitoring Network (NGWMN) envisioned as a voluntary, integrated system of data collection, management and reporting that will provide the data needed to address present and future ground-water management questions raised by Congress, Federal, State and Tribal agencies and the public. The NGWMN Data Portal is the means by which policy makers, academics and the public will be able to access ground water data through one seamless web-based application from disparate data sources. Data systems in the United States exist at many organizational and geographic levels and differing vocabulary and data structures have prevented data sharing and reuse. The data portal will facilitate the retrieval of and access to groundwater data on an as-needed basis from multiple, dispersed data repositories allowing the data to continue to be housed and managed by the data provider while being accessible for the purposes of the national monitoring network. This work leverages Open Geospatial Consortium (OGC) data exchange standards and information models. To advance these standards for supporting the exchange of ground water information, an OGC Interoperability Experiment was organized among international participants from government, academia and the private sector. The experiment focused on ground water data exchange across the U.S. / Canadian border. WaterML2.0, an evolving international standard for water observations, encodes ground water levels and is exchanged

  7. Optimal reliability design for over-actuated systems based on the MIT rule: Application to an octocopter helicopter testbed

    International Nuclear Information System (INIS)

    Chamseddine, Abbas; Theilliol, Didier; Sadeghzadeh, Iman; Zhang, Youmin; Weber, Philippe

    2014-01-01

    This paper addresses the problem of optimal reliability in over-actuated systems. Overloading an actuator decreases its overall lifetime and reduces its average performance over a long time. Therefore, performance and reliability are two conflicting requirements. While appropriate reliability is related to average loads, good performance is related to fast response and sufficient loads generated by actuators. Actuator redundancy allows us to address both performance and reliability at the same time by properly allocating desired loads among redundant actuators. The main contribution of this paper is the on-line optimization of the overall plant reliability according to performance objective using an MIT (Massachusetts Institute of Technology) rule-based method. The effectiveness of the proposed method is illustrated through an experimental application to an octocopter helicopter testbed

  8. Nitrate Removal from Ground Water: A Review

    Directory of Open Access Journals (Sweden)

    Archna

    2012-01-01

    Full Text Available Nitrate contamination of ground water resources has increased in Asia, Europe, United States, and various other parts of the world. This trend has raised concern as nitrates cause methemoglobinemia and cancer. Several treatment processes can remove nitrates from water with varying degrees of efficiency, cost, and ease of operation. Available technical data, experience, and economics indicate that biological denitrification is more acceptable for nitrate removal than reverse osmosis and ion exchange. This paper reviews the developments in the field of nitrate removal processes which can be effectively used for denitrifying ground water as well as industrial water.

  9. Improving Flight Software Module Validation Efforts : a Modular, Extendable Testbed Software Framework

    Science.gov (United States)

    Lange, R. Connor

    2012-01-01

    Ever since Explorer-1, the United States' first Earth satellite, was developed and launched in 1958, JPL has developed many more spacecraft, including landers and orbiters. While these spacecraft vary greatly in their missions, capabilities,and destination, they all have something in common. All of the components of these spacecraft had to be comprehensively tested. While thorough testing is important to mitigate risk, it is also a very expensive and time consuming process. Thankfully,since virtually all of the software testing procedures for SMAP are computer controlled, these procedures can be automated. Most people testing SMAP flight software (FSW) would only need to write tests that exercise specific requirements and then check the filtered results to verify everything occurred as planned. This gives developers the ability to automatically launch tests on the testbed, distill the resulting logs into only the important information, generate validation documentation, and then deliver the documentation to management. With many of the steps in FSW testing automated, developers can use their limited time more effectively and can validate SMAP FSW modules quicker and test them more rigorously. As a result of the various benefits of automating much of the testing process, management is considering this automated tools use in future FSW validation efforts.

  10. Older persons’ and their families’ experience with live-in foreign home care workers. A grounded theory study

    Science.gov (United States)

    Petry, Heidi; Naef, Rahel; Rüesch, Peter; Mahrer-Imhof, Romy; Dreizler, Jutta

    2016-11-01

    Background: Live-in arrangements with migrant care workers have considerably increased over the last years since they allow older frail persons to age-in-place despite functional limitations. However, little is known about the ramifications live-in care arrangements for families. Aim: The aim of the study was to investigate families’ experience with live-in migrant care workers and indicators of quality from their perspective. Method: Constructivist grounded theory study with 22 families who were recruited via care agencies in the German-speaking part of Switzerland and participated in 29 individual or dyadic interviews. Results: Live-in care by migrant care workers has potentially positive ramifications for older persons and their families, but only so if families, first, reach a consensus about the need for the employment of migrant care workers; second, experience them as competent; and third, mutually forge relationships and negotiate daily life. A successful care arrangement occurs when there is a relational fit among those involved, which leaves families feeling cared for, safe and relieved. They experience a renewed stability in their family system, enriching relationships, and assuredness about the quality present in the care situation. Conclusions: A successful care arrangement is the result of relationships that have been actively created and a negotiated shared existence in a family-like network. It has a positive effect on the well-being of those receiving care and their family members. The family-like network needs competent support.

  11. Atomic oxygen effects on boron nitride and silicon nitride: A comparison of ground based and space flight data

    Science.gov (United States)

    Cross, J. B.; Lan, E. H.; Smith, C. A.; Whatley, W. J.

    1990-01-01

    The effects of atomic oxygen on boron nitride (BN) and silicon nitride (Si3N4) were evaluated in a low Earth orbit (LEO) flight experiment and in a ground based simulation facility. In both the inflight and ground based experiments, these materials were coated on thin (approx. 250A) silver films, and the electrical resistance of the silver was measured in situ to detect any penetration of atomic oxygen through the BN and Si3N4 materials. In the presence of atomic oxygen, silver oxidizes to form silver oxide, which has a much higher electrical resistance than pure silver. Permeation of atomic oxygen through BN, as indicated by an increase in the electrical resistance of the silver underneath, was observed in both the inflight and ground based experiments. In contrast, no permeation of atomic oxygen through Si3N4 was observed in either the inflight or ground based experiments. The ground based results show good qualitative correlation with the LEO flight results, indicating that ground based facilities such as the one at Los Alamos National Lab can reproduce space flight data from LEO.

  12. Figure/ground segregation from temporal delay is best at high spatial frequencies

    OpenAIRE

    Kojima, Haruyuki

    1998-01-01

    Two experiments investigated the role of spatial frequency in performance of a figure/ground segregation task based on temporal cues. Figure orientation was much easier to judge when figure and ground portions of the target were defined exclusively by random texture composed entirely of high spatial frequencies. When target components were defined by low spatial frequencies only, the task was nearly impossible except with long temporal delay between figure and ground. These results are incons...

  13. Consumers' willingness to pay for irradiated prepared ground beef

    International Nuclear Information System (INIS)

    Nayga, R.M. Jr.; Woodward, R.; Aiew, W.

    2009-01-01

    This paper focuses on estimating willingness to pay for reducing the risk of contracting foodborne illness using a non-hypothetical experiment utilizing real food products (i.e. prepared ground beef), real cash and actual exchange in a market setting. Respondents were given positive information about the nature of food irradiation. Single bounded and one and one-half bounded models are developed using dichotomous choice experiments. The results indicate that individuals are willing to pay for a reduction in the risk of foodborne illness once informed about the nature of food irradiation. Respondents are willing to pay a premium of about US $0.77 for 450 g (1 pound) of irradiated ground beef, which is higher than the cost of irradiating the product. (author)

  14. Experience with remediating radiostrontium-contaminated ground water and surface water with versions of AECL's CHEMIC process

    International Nuclear Information System (INIS)

    Vijayan, S.

    2006-01-01

    Numerous approaches have been developed for the remediation of radiostrontium ( 90 Sr) contaminated ground water and surface water. Several strontium-removal technologies have been assessed and applied at AECL's (Atomic Energy of Canada Limited) Chalk River Laboratories. These include simple ion exchange (based on non-selective natural zeolites or selective synthetic inorganic media), and precipitation and filtration with or without ion exchange as a final polishing step. AECL's CHEMIC process is based on precipitation-microfiltration and ion-exchange steps. This paper presents data related to radiostrontium removal performance and other operational experiences including troubleshooting with two round-the-clock, pilot-scale water remediation plants based on AECL's CHEMIC process at the Chalk River Laboratories site. These plants began operation in the early 1990s. Through optimization of process chemistry and operation, high values for system capability and system availability factors, and low concentrations of 90 Sr in the discharge water approaching drinking water standard can be achieved. (author)

  15. Infrasonic induced ground motions

    Science.gov (United States)

    Lin, Ting-Li

    On January 28, 2004, the CERI seismic network recorded seismic signals generated by an unknown source. Our conclusion is that the acoustic waves were initiated by an explosive source near the ground surface. The meteorological temperature and effective sound speed profiles suggested existence of an efficient near-surface waveguide that allowed the acoustic disturbance to propagate to large distances. An explosion occurring in an area of forest and farms would have limited the number of eyewitnesses. Resolution of the source might be possible by experiment or by detailed analysis of the ground motion data. A seismo-acoustic array was built to investigate thunder-induced ground motions. Two thunder events with similar N-wave waveforms but different horizontal slownesses are chosen to evaluate the credibility of using thunder as a seismic source. These impulsive acoustic waves excited P and S reverberations in the near surface that depend on both the incident wave horizontal slowness and the velocity structure in the upper 30 meters. Nineteen thunder events were chosen to further investigate the seismo-acoustic coupling. The consistent incident slowness differences between acoustic pressure and ground motions suggest that ground reverberations were first initiated somewhat away from the array. Acoustic and seismic signals were used to generate the time-domain transfer function through the deconvolution technique. Possible non-linear interaction for acoustic propagation into the soil at the surface was observed. The reverse radial initial motions suggest a low Poisson's ratio for the near-surface layer. The acoustic-to-seismic transfer functions show a consistent reverberation series of the Rayleigh wave type, which has a systematic dispersion relation to incident slownesses inferred from the seismic ground velocity. Air-coupled Rayleigh wave dispersion was used to quantitatively constrain the near-surface site structure with constraints afforded by near-surface body

  16. A test-bed modeling study for wave resource assessment

    Science.gov (United States)

    Yang, Z.; Neary, V. S.; Wang, T.; Gunawan, B.; Dallman, A.

    2016-02-01

    Hindcasts from phase-averaged wave models are commonly used to estimate standard statistics used in wave energy resource assessments. However, the research community and wave energy converter industry is lacking a well-documented and consistent modeling approach for conducting these resource assessments at different phases of WEC project development, and at different spatial scales, e.g., from small-scale pilot study to large-scale commercial deployment. Therefore, it is necessary to evaluate current wave model codes, as well as limitations and knowledge gaps for predicting sea states, in order to establish best wave modeling practices, and to identify future research needs to improve wave prediction for resource assessment. This paper presents the first phase of an on-going modeling study to address these concerns. The modeling study is being conducted at a test-bed site off the Central Oregon Coast using two of the most widely-used third-generation wave models - WaveWatchIII and SWAN. A nested-grid modeling approach, with domain dimension ranging from global to regional scales, was used to provide wave spectral boundary condition to a local scale model domain, which has a spatial dimension around 60km by 60km and a grid resolution of 250m - 300m. Model results simulated by WaveWatchIII and SWAN in a structured-grid framework are compared to NOAA wave buoy data for the six wave parameters, including omnidirectional wave power, significant wave height, energy period, spectral width, direction of maximum directionally resolved wave power, and directionality coefficient. Model performance and computational efficiency are evaluated, and the best practices for wave resource assessments are discussed, based on a set of standard error statistics and model run times.

  17. Grounded theory.

    Science.gov (United States)

    Harris, Tina

    2015-04-29

    Grounded theory is a popular research approach in health care and the social sciences. This article provides a description of grounded theory methodology and its key components, using examples from published studies to demonstrate practical application. It aims to demystify grounded theory for novice nurse researchers, by explaining what it is, when to use it, why they would want to use it and how to use it. It should enable nurse researchers to decide if grounded theory is an appropriate approach for their research, and to determine the quality of any grounded theory research they read.

  18. Brain bases for auditory stimulus-driven figure-ground segregation.

    Science.gov (United States)

    Teki, Sundeep; Chait, Maria; Kumar, Sukhbinder; von Kriegstein, Katharina; Griffiths, Timothy D

    2011-01-05

    Auditory figure-ground segregation, listeners' ability to selectively hear out a sound of interest from a background of competing sounds, is a fundamental aspect of scene analysis. In contrast to the disordered acoustic environment we experience during everyday listening, most studies of auditory segregation have used relatively simple, temporally regular signals. We developed a new figure-ground stimulus that incorporates stochastic variation of the figure and background that captures the rich spectrotemporal complexity of natural acoustic scenes. Figure and background signals overlap in spectrotemporal space, but vary in the statistics of fluctuation, such that the only way to extract the figure is by integrating the patterns over time and frequency. Our behavioral results demonstrate that human listeners are remarkably sensitive to the appearance of such figures. In a functional magnetic resonance imaging experiment, aimed at investigating preattentive, stimulus-driven, auditory segregation mechanisms, naive subjects listened to these stimuli while performing an irrelevant task. Results demonstrate significant activations in the intraparietal sulcus (IPS) and the superior temporal sulcus related to bottom-up, stimulus-driven figure-ground decomposition. We did not observe any significant activation in the primary auditory cortex. Our results support a role for automatic, bottom-up mechanisms in the IPS in mediating stimulus-driven, auditory figure-ground segregation, which is consistent with accumulating evidence implicating the IPS in structuring sensory input and perceptual organization.

  19. Ultimate turbulence experiment: simultaneous measurements of Cn2 near the ground using six devices and eight methods

    Science.gov (United States)

    Yatcheva, Lydia; Barros, Rui; Segel, Max; Sprung, Detlev; Sucher, Erik; Eisele, Christian; Gladysz, Szymon

    2015-10-01

    We have performed a series of experiments in order to simultaneously validate several devices and methods for measurement of the path-averaged refractive index structure constant ( 𝐶𝑛 2). The experiments were carried out along a horizontal urban path near the ground. Measuring turbulence in this layer is particularly important because of the prospect of using adaptive optics for free-space optical communications in an urban environment. On one hand, several commercial sensors were used: SLS20, a laser scintillometer from Scintec AG, BLS900, a largeaperture scintillometer, also from Scintec, and a 3D sonic anemometer from Thies GmbH. On the other hand, we measured turbulence strength with new approaches and devices developed in-house. Firstly, an LED array combined with a high-speed camera allowed for measurement of 𝐶𝑛 2 from raw- and differential image motion, and secondly a two-part system comprising a laser source, a Shack-Hartmann sensor and a PSF camera recoded turbulent modulation transfer functions, Zernike variances and angle-of-arrival structure functions, yielding three independent estimates of 𝐶𝑛 2. We compare the measured values yielded simultaneously by commercial and in-house developed devices and show very good agreement between 𝐶𝑛 2 values for all the methods. Limitations of each experimental method are also discussed.

  20. Regional analysis of ground and above-ground climate

    Science.gov (United States)

    1981-12-01

    The regional suitability of underground construction as a climate control technique is discussed with reference to (1) a bioclimatic analysis of long term weather data for 29 locations in the United States to determine appropriate above ground climate control techniques, (2) a data base of synthesized ground temperatures for the coterminous United States, and (3) monthly dew point ground temperature comparisons for identifying the relative likelihood of condensation from one region to another. It is concluded that the suitability of Earth tempering as a practice and of specific Earth sheltered design stereotypes varies geographically; while the subsurface almost always provides a thermal advantage on its own terms when compared to above ground climatic data, it can, nonetheless, compromise the effectiveness of other, regionally more important climate control techniques. Reviews of above and below ground climate mapping schemes related to human comfort and architectural design, and detailed description of a theoretical model of ground temperature, heat flow, and heat storage in the ground are included. Strategies of passive climate control are presented in a discussion of the building bioclimatic analysis procedure which has been applied in a computer analysis of 30 years of weather data for each of 20 locations in the United States.