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Sample records for converter station design

  1. Optimal design of AC filter circuits in HVDC converter stations

    SciTech Connect

    Saied, M.M.; Khader, S.A.

    1995-12-31

    This paper investigates the reactive power as well as the harmonic conditions on both the valve and the AC-network sides of a HVDC converter station. The effect of the AC filter circuits is accurately modeled. The program is then augmented by adding an optimization routine. It can identify the optimal filter configuration, yielding the minimum current distortion factor at the AC network terminals for a prespecified fundamental reactive power to be provided by the filter. Several parameter studies were also conducted to illustrate the effect of accidental or intentional deletion of one of the filter branches.

  2. A computer program for HVDC converter station RF noise calculations

    SciTech Connect

    Kasten, D.G.; Caldecott, R.; Sebo, S.A. . Dept. of Electrical Engineering); Liu, Y. . Bradley Dept. of Electrical Engineering)

    1994-04-01

    HVDC converter station operations generate radio frequency (RF) electromagnetic (EM) noise which could interfere with adjacent communication and computer equipment, and carrier system operations. A generic Radio Frequency Computer Analysis Program (RAFCAP) for calculating the EM noise generated by valve ignition of a converter station has been developed as part of a larger project. The program calculates RF voltages, currents, complex power, ground level electric field strength and magnetic flux density in and around an HVDC converter station. The program requires the converter station network to be represented by frequency dependent impedance functions. Comparisons of calculated and measured values are given for an actual HVDC station to illustrate the validity of the program. RAFCAP is designed to be used by engineers for the purpose of calculating the RF noise produced by the igniting of HVDC converter valves.

  3. Weather satellite picture receiving stations, APT digital scan converter

    NASA Technical Reports Server (NTRS)

    Vermillion, C. H.; Kamowski, J. C.

    1975-01-01

    The automatic picture transmission digital scan converter is used at ground stations to convert signals received from scanning radiometers to data compatible with ground equipment designed to receive signals from vidicons aboard operational meteorological satellites. Information necessary to understand the circuit theory, functional operation, general construction and calibration of the converter is provided. Brief and detailed descriptions of each of the individual circuits are included, accompanied by a schematic diagram contained at the end of each circuit description. Listings of integral parts and testing equipment required as well as an overall wiring diagram are included. This unit will enable the user to readily accept and process weather photographs from the operational meteorological satellites.

  4. Space Station design integration

    NASA Technical Reports Server (NTRS)

    Carlisle, Richard F.

    1988-01-01

    This paper discusses the top Program level design integration process which involves the integration of a US Space Station manned base that consists of both US and international Elements. It explains the form and function of the Program Requirements Review (PRR), which certifies that the program is ready for preliminary design, the Program Design Review (PDR), which certifies the program is ready to start the detail design, and the Critical Design Review (CDR), which certifies that the program is completing a design that meets the Program objectives. The paper also discusses experience, status to date, and plans for continued system integration through manufacturing, testing and final verification of the Space Station system performance.

  5. Power Station Design

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Kuljian Corporation provides design engineering and construction management services for power generating plants in more than 20 countries. They used WASP (Calculating Water and Steam Properties), a COSMIC program to optimize power station design. This enabled the company to substantially reduce lead time and software cost in a recent design project.

  6. Designing a Weather Station

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2012-01-01

    The collection and analysis of weather data is crucial to the location of alternate energy systems like solar and wind. This article presents a design challenge that gives students a chance to design a weather station to collect data in advance of a large wind turbine installation. Data analysis is a crucial part of any science or engineering…

  7. Space Station Engineering Design Issues

    NASA Technical Reports Server (NTRS)

    Mcruer, Duane T.; Boehm, Barry W.; Debra, Daniel B.; Green, C. Cordell; Henry, Richard C.; Maycock, Paul D.; Mcelroy, John H.; Pierce, Chester M.; Stafford, Thomas P.; Young, Laurence R.

    1989-01-01

    Space Station Freedom topics addressed include: general design issues; issues related to utilization and operations; issues related to systems requirements and design; and management issues relevant to design.

  8. Designing Space Station

    NASA Technical Reports Server (NTRS)

    1986-01-01

    An overview of preparations for the construction of Space Station Freedom (SSF) is presented. The video includes footage of astronauts testing materials for erectable structures in space both in the Shuttle bay while in orbit and in a neutral buoyancy tank at McDonald Douglas' Underwater Test Facility. Also shown are footage of robot systems that will assist the astronauts in building SSF, a computer simulation of an Orbiting Maneuvering Vehicle, solar dynamic mirrors that will power SSF, and mockups of the living quarters of the SSF.

  9. Modelling, analyses and design of switching converters

    NASA Technical Reports Server (NTRS)

    Cuk, S. M.; Middlebrook, R. D.

    1978-01-01

    A state-space averaging method for modelling switching dc-to-dc converters for both continuous and discontinuous conduction mode is developed. In each case the starting point is the unified state-space representation, and the end result is a complete linear circuit model, for each conduction mode, which correctly represents all essential features, namely, the input, output, and transfer properties (static dc as well as dynamic ac small-signal). While the method is generally applicable to any switching converter, it is extensively illustrated for the three common power stages (buck, boost, and buck-boost). The results for these converters are then easily tabulated owing to the fixed equivalent circuit topology of their canonical circuit model. The insights that emerge from the general state-space modelling approach lead to the design of new converter topologies through the study of generic properties of the cascade connection of basic buck and boost converters.

  10. Efficient Design in a DC to DC Converter Unit

    NASA Technical Reports Server (NTRS)

    Bruemmer, Joel E.; Williams, Fitch R.; Schmitz, Gregory V.

    2002-01-01

    Space Flight hardware requires high power conversion efficiencies due to limited power availability and weight penalties of cooling systems. The International Space Station (ISS) Electric Power System (EPS) DC-DC Converter Unit (DDCU) power converter is no exception. This paper explores the design methods and tradeoffs that were utilized to accomplish high efficiency in the DDCU. An isolating DC to DC converter was selected for the ISS power system because of requirements for separate primary and secondary grounds and for a well-regulated secondary output voltage derived from a widely varying input voltage. A flyback-current-fed push-pull topology or improved Weinberg circuit was chosen for this converter because of its potential for high efficiency and reliability. To enhance efficiency, a non-dissipative snubber circuit for the very-low-Rds-on Field Effect Transistors (FETs) was utilized, redistributing the energy that could be wasted during the switching cycle of the power FETs. A unique, low-impedance connection system was utilized to improve contact resistance over a bolted connection. For improved consistency in performance and to lower internal wiring inductance and losses a planar bus system is employed. All of these choices contributed to the design of a 6.25 KW regulated dc to dc converter that is 95 percent efficient. The methodology used in the design of this DC to DC Converter Unit may be directly applicable to other systems that require a conservative approach to efficient power conversion and distribution.

  11. Thermophotovoltaic Converter Design for Radioisotope Power Systems

    SciTech Connect

    Crowley, Christopher J.; Elkouh, Nabil A.; Murray, Susan; Murray, Christopher

    2004-02-04

    The development of lightweight, efficient power for emerging NASA missions and recent advances in thermophotovoltaic (TPV) conversion technology have renewed interest in combining radioisotope heat sources with photovoltaic energy conversion. Thermophotovoltaic power conversion uses advanced materials able to utilize a broader, spectrally tuned range of wavelengths for more efficient power conversion than solar cells. Spectral control, including selective emitters, TPV module, and filters, are key to high-efficiency operation. This paper outlines the mechanical, thermal, and optical designs for the converter, including the heat source, the selective emitter, filters, photovoltaic (PV) cells, and optical cavity components. Focus is on the emitter type and the band-gap of InGaAs PV cells in developing the design. Any component and converter data available at the time of publication will also be presented.

  12. Stability of large DC power systems using switching converters, with application to the international space station

    NASA Technical Reports Server (NTRS)

    Manners, B.; Gholdston, E. W.; Karimi, K.; Lee, F. C.; Rajagopalan, J.; Panov, Y.

    1996-01-01

    As space direct current (dc) power systems continue to grow in size, switching power converters are playing an ever larger role in power conditioning and control. When designing a large dc system using power converters of this type, special attention must be placed on the electrical stability of the system and of the individual loads on the system. In the design of the electric power system (EPS) of the International Space Station (ISS), the National Aeronautics and Space Administration (NASA) and its contractor team led by Boeing Defense & Space Group has placed a great deal of emphasis on designing for system and load stability. To achieve this goal, the team has expended considerable effort deriving a dear concept on defining system stability in both a general sense and specifically with respect to the space station. The ISS power system presents numerous challenges with respect to system stability, such as high power, complex sources and undefined loads. To complicate these issues, source and load components have been designed in parallel by three major subcontractors (Boeing, Rocketdyne, and McDonnell Douglas) with interfaces to both sources and loads being designed in different countries (Russia, Japan, Canada, Europe, etc.). These issues, coupled with the program goal of limiting costs, have proven a significant challenge to the program. As a result, the program has derived an impedance specification approach for system stability. This approach is based on the significant relationship between source and load impedances and the effect of this relationship on system stability. This approach is limited in its applicability by the theoretical and practical limits on component designs as presented by each system segment. As a result, the overall approach to system stability implemented by the ISS program consists of specific hardware requirements coupled with extensive system analysis and hardware testing. Following this approach, the ISS program plans to begin

  13. Performance testing of a high frequency link converter for Space Station power distribution system

    NASA Technical Reports Server (NTRS)

    Sul, S. K.; Alan, I.; Lipo, T. A.

    1989-01-01

    The testing of a brassboard version of a 20-kHz high-frequency ac voltage link prototype converter dynamics for Space Station application is presented. The converter is based on a three-phase six-pulse bridge concept. The testing includes details of the operation of the converter when it is driving an induction machine source/load. By adapting a field orientation controller (FOC) to the converter, four-quadrant operation of the induction machine from the converter has been achieved. Circuit modifications carried out to improve the performance of the converter are described. The performance of two 400-Hz induction machines powered by the converter with simple V/f regulation mode is reported. The testing and performance results for the converter utilizing the FOC, which provides the capability for rapid torque changes, speed reversal, and four-quadrant operation, are reported.

  14. Load converter interactions with the secondary system in the Space Station Freedom power management and distribution dc test bed

    NASA Technical Reports Server (NTRS)

    Lebron, Ramon C.

    1992-01-01

    The NASA LeRC in Cleveland, Ohio, is responsible for the design, development, and assembly of the Space Station Freedom (SSF) Electrical Power System (EPS). In order to identify and understand system level issues during the SSF program design and development phases, a system Power Management and Distribution (PMAD) dc test bed was assembled. Some of the objectives of this test bed facility are the evaluation of, system efficiency, power quality, system stability, and system protection and reconfiguration schemes. In order to provide a realistic operating scenario, dc Load Converter Units are used in the PMAD dc test bed to characterize the user interface with the power system. These units are dc to dc converters that provide the final system regulation before power is delivered to the load. This final regulation is required on the actual space station because the majority of user loads will require voltage levels different from the secondary bus voltage. This paper describes the testing of load converters in an end to end system environment (from solar array to loads) where their interactions and compatibility with other system components are considered. Some of the system effects of interest that are presented include load converters transient behavior interactions with protective current limiting switchgear, load converters ripple effects, and the effects of load converter constant power behavior with protective features such as foldback.

  15. Load converter interactions with the secondary system in the Space Station Freedom power management and distribution DC test bed

    NASA Technical Reports Server (NTRS)

    Lebron, Ramon C.

    1992-01-01

    The NASA LeRC in Cleveland, Ohio, is responsible for the design, development, and assembly of the Space Station Freedom (SSF) Electrical Power System (EPS). In order to identify and understand system level issues during the SSF Program design and development phases, a system Power Management and Distribution (PMAD) DC test bed was assembled. Some of the objectives of this test bed facility are the evaluation of, system efficiency, power quality, system stability, and system protection and reconfiguration schemes. In order to provide a realistic operating scenario, dc Load Converter Units are used in the PMAD dc test bed to characterize the user interface with the power system. These units are dc to dc converters that provide the final system regulation before power is delivered to the load. This final regulation is required on the actual space station because the majority of user loads will require voltage levels different from the secondary bus voltage. This paper describes the testing of load converters in an end to end system environment (from solar array to loads) where their interactions and compatibility with other system components are considered. Some of the system effects of interest that are presented include load converters transient behavior interactions with protective current limiting switchgear, load converters ripple effects, and the effects of load converter constant power behavior with protective features such as foldback.

  16. DC-DC power converter research for Orbiter/Station power exchange

    NASA Technical Reports Server (NTRS)

    Ehsani, M.

    1993-01-01

    This project was to produce innovative DC-DC power converter concepts which are appropriate for the power exchange between the Orbiter and the Space Station Freedom (SSF). The new converters must interface three regulated power buses on SSF, which are at different voltages, with three fuel cell power buses on the Orbiter which can be at different voltages and should be tracked independently. Power exchange is to be bi-directional between the SSF and the Orbiter. The new converters must satisfy the above operational requirements with better weight, volume, efficiency, and reliability than is available from the present conventional technology. Two families of zero current DC-DC converters were developed and successfully adapted to this application. Most of the converters developed are new and are presented.

  17. Stability of Large Direct-Current Power Systems That Use Switching Converters and the Application of Switching Converters to the International Space Station

    NASA Technical Reports Server (NTRS)

    Manners, Bruce A.; Gholdston, E. W.; Karimi, K.; Lee, F. C.; Rajagopalan, J.; Panov, Y.

    1997-01-01

    As direct-current space power systems continue to grow in size, switching power converters are playing an ever larger role in power conditioning and control. When a large direct-current system that uses power converters of this type is being designed, special attention must be placed on the electrical stability of the system and of the individual loads on the system. The impedance specification approach for system stability was accomplished as a result of cooperative work of the International Space Station program team, which consists of the NASA Lewis Research Center, the Boeing Company, and Rocketdyne Division/Rockwell International. In addition, major contributions were provided by the Virginia Polytechnic Institute and State University working under a grant to NASA Lewis.

  18. Buck-boost converter feedback controller design via evolutionary search

    NASA Astrophysics Data System (ADS)

    Sundareswaran, K.; Devi, V.; Nadeem, S. K.; Sreedevi, V. T.; Palani, S.

    2010-11-01

    Buck-boost converters are switched power converters. The model of the converter system varies from the ON state to the OFF state and hence traditional methods of controller design based on approximate transfer function models do not yield good dynamic response at different operating points of the converter system. This article attempts to design a feedback controller for a buck-boost type dc-dc converter using a genetic algorithm. The feedback controller design is perceived as an optimisation problem and a robust controller is estimated through an evolutionary search. Extensive simulation and experimental results provided in the article show the effectiveness of the new approach.

  19. Converter design techniques and applications. [transistorized voltage converters for aerospace systems

    NASA Technical Reports Server (NTRS)

    Lalli, V. R.

    1974-01-01

    The design of transistorized voltage converters of the series, shunt, and switching types is developed and explained. The shunt converter has the smallest size, lowest weight, and lowest parts count. Regulation and stability are very good but efficiency is poor. The series converter is somewhat larger in size, heavier, uses more parts, and has an order of magnitude (10 to 1) decrease in regulation performance in comparison with the shunt converter. The switching converter tends to be a compromise with increased size, weight, and circuit complexity to gain in efficiency and regulation over a series converter. A switching converter will usually exhibit ringing in the output filter for some types of loads so it has only fair stability performance.-

  20. Space Station communications system design and analysis

    NASA Technical Reports Server (NTRS)

    Ratliff, J. E.

    1986-01-01

    Attention is given to the methodologies currently being used as the framework within which the NASA Space Station's communications system is to be designed and analyzed. A key aspect of the CAD/analysis system being employed is its potential growth in size and capabilities, since Space Station design requirements will continue to be defined and modified. The Space Station is expected to furnish communications between itself and astronauts on EVA, Orbital Maneuvering Vehicles, Orbital Transfer Vehicles, Space Shuttle orbiters, free-flying spacecraft, coorbiting platforms, and the Space Shuttle's own Mobile Service Center.

  1. Radiation effects in power converters: Design of a radiation hardened integrated switching DC/DC converter

    NASA Astrophysics Data System (ADS)

    Adell, Philippe

    When electronic devices are used in space and military systems, they may be exposed to various types of radiation, including photons, electrons, protons, neutrons, and heavy ions. The effects of radiation on the semiconductor devices within the systems range from gradual degradation to catastrophic failure. In order to design and produce reliable systems for space or military applications, it is necessary to understand the device-level effects of radiation and develop appropriate strategies for reducing system susceptibility. This research focuses on understanding radiation effects in power converters for space and military applications. We show that power converters are very sensitive to radiation (total-dose, single event effects and displacement damage) and that their radiation response is dependent on input bias conditions and load conditions. We compared the radiation hardness of various power converter topologies using experiments and simulations. Evaluation of these designs under different modes of operation is demonstrated to be critical for determining radiation hardness. We emphasize the correlation between radiation effects and the role of the dynamic response of these topologies. For instance, total dose exposure has been found to degrade loop gain and affect regulation in some converters. We propose several radiation-hardening solutions to improve the radiation response of these designs. For instance, we demonstrate the design of a digitally controlled boost converter suitable for space applications based on an SRAM FPGA. A design hardening solution has been developed and successfully applied through VHDL simulations and experiments to assure the continuous operation of the converter in the presence of SEES (more precisely SEFIs). This research led to the design of a digitally controlled radiation hardened integrated switching buck converter. The proposed design is suitable for micro-satellite applications and is based on a high-voltage/CMOS process

  2. Space station prototype Sabatier reactor design verification testing

    NASA Technical Reports Server (NTRS)

    Cusick, R. J.

    1974-01-01

    A six-man, flight prototype carbon dioxide reduction subsystem for the SSP ETC/LSS (Space Station Prototype Environmental/Thermal Control and Life Support System) was developed and fabricated for the NASA-Johnson Space Center between February 1971 and October 1973. Component design verification testing was conducted on the Sabatier reactor covering design and off-design conditions as part of this development program. The reactor was designed to convert a minimum of 98 per cent hydrogen to water and methane for both six-man and two-man reactant flow conditions. Important design features of the reactor and test conditions are described. Reactor test results are presented that show design goals were achieved and off-design performance was stable.

  3. Space station preliminary design report

    NASA Technical Reports Server (NTRS)

    1982-01-01

    The results of a 3 month preliminary design and analysis effort is presented. The configuration that emerged consists of a very stiff deployable truss structure with an overall triangular cross section having universal modules attached at the apexes. Sufficient analysis was performed to show feasibility of the configuration. An evaluation of the structure shows that desirable attributes of the configuration are: (1) the solar cells, radiators, and antennas will be mounted to stiff structure to minimize control problems during orbit maintenance and correction, docking, and attitude control; (2) large flat areas are available for mounting and servicing of equipment; (3) Large mass items can be mounted near the center of gravity of the system to minimize gravity gradient torques; (4) the trusses are lightweight structures and can be transported into orbit in one Shuttle flight; (5) the trusses are expandable and will require a minimum of EVA; and (6) the modules are anticipated to be structurally identical except for internal equipment to minimize cost.

  4. Technical Design Report, Second Target Station

    SciTech Connect

    Galambos, John D.; Anderson, David E.; Bechtol, D.; Bethea, Katie L.; Brown, N.; Carden, W. F.; Chae, Steven M.; Clark, A.; Counce, Deborah M.; Craft, K.; Crofford, Mark T.; Collins, Richard M.; Cousineau, Sarah M.; Curry, Douglas E.; Cutler, Roy I.; Dayton, Michael J.; Dean, Robert A.; Deibele, Craig E.; Doleans, Marc; Dye, T.; Eason, Bob H.; Eckroth, James A.; Fincrock, C.; Fritts, S.; Gallmeier, Franz X.; Gawne, Ken R.; Hartman, Steven M.; Herwig, Kenneth W.; Hess, S.; Holmes, Jeffrey A.; Horak, Charlie M.; Howell, Matthew P.; Iverson, Erik B.; Jacobs, Lorelei L.; Jones, Larry C.; Johnson, B.; Johnson, S.; Kasemir, Kay; Kim, Sang-Ho; Laughon, Gregory J.; Lu, W.; Mahoney, Kelly L.; Mammosser, John; McManamy, T.; Michilini, M.; Middendorf, Mark E.; O'Neal, Ed; Nemec, B.; Peters, Roy Cecil; Plum, Michael A.; Reagan, G.; Remec, Igor; Rennich, Mark J.; Riemer, Bernie; Saethre, Robert B.; Schubert, James Phillip; Shishlo, Andrei P.; Smith, C. Craig; Strong, William Herb; Tallant, Kathie M.; Tennant, David Alan; Thibadeau, Barbara M.; Trumble, S.; Trotter, Steven M.; Wang, Z.; Webb, Steven B.; Williams, Derrick C.; White, Karen S.; Zhao, Jinkui

    2015-01-01

    The Second Target Station (STS) is a proposed upgrade for SNS. It includes a doubling of the accelerator power and an additional instrument hall. The new instrument hall will receive a 467 kW 10 Hz beam. The parameters and preliminary design aspects of the STS are presented for the accelerator, target systems, instrument hall, instruments and civil construction aspects.

  5. Guide for Identifying and Converting High-Potential Petroleum Brownfield Sites to Alternative Fuel Stations

    SciTech Connect

    Johnson, C.; Hettinger, D.; Mosey, G.

    2011-05-01

    Former gasoline stations that are now classified as brownfields can be good sites to sell alternative fuels because they are in locations that are convenient to vehicles and they may be seeking a new source of income. However, their success as alternative fueling stations is highly dependent on location-specific criteria. First, this report outlines what these criteria are, how to prioritize them, and then applies that assessment framework to five of the most popular alternative fuels--electricity, natural gas, hydrogen, ethanol, and biodiesel. The second part of this report delves into the criteria and tools used to assess an alternative fuel retail site at the local level. It does this through two case studies of converting former gasoline stations in the Seattle-Eugene area into electric charge stations. The third part of this report addresses steps to be taken after the specific site has been selected. This includes choosing and installing the recharging equipment, which includes steps to take in the permitting process and key players to include.

  6. Space station proximity operations and window design

    NASA Technical Reports Server (NTRS)

    Haines, Richard F.

    1988-01-01

    On-orbit proximity operations (PROX-OPS) consist of all extravehicular activity (EVA) within 1 km of the space station. Because of the potentially large variety of PROX-OPS, very careful planning for space station windows is called for and must consider a great many human factors. The following topics are discussed: (1) basic window design philosophy and assumptions; (2) the concept of the local horizontal - local vertical on-orbit; (3) window linear dimensions; (4) selected anthropomorphic considerations; (5) displays and controls relative to windows; and (6) full window assembly replacement.

  7. Operator Station Design System - A computer aided design approach to work station layout

    NASA Technical Reports Server (NTRS)

    Lewis, J. L.

    1979-01-01

    The Operator Station Design System is resident in NASA's Johnson Space Center Spacecraft Design Division Performance Laboratory. It includes stand-alone minicomputer hardware and Panel Layout Automated Interactive Design and Crew Station Assessment of Reach software. The data base consists of the Shuttle Transportation System Orbiter Crew Compartment (in part), the Orbiter payload bay and remote manipulator (in part), and various anthropometric populations. The system is utilized to provide panel layouts, assess reach and vision, determine interference and fit problems early in the design phase, study design applications as a function of anthropometric and mission requirements, and to accomplish conceptual design to support advanced study efforts.

  8. Design and operation of a thermionic converter in air

    NASA Astrophysics Data System (ADS)

    Horner, M. Harlan; Begg, Lester L.; Smith, Joe N., Jr.; Geller, Clint B.; Kalinowski, Joseph E.

    An electrically heated thermionic converter has been designed, built and successfully tested in air. Several unique features were incorporated in this converter: an integral cesium reservoir, innovative ceramic-to-metal seals, a heat rejection system coupling the collector to a low temperature heat sink and an innovative cylindrical heater filament. The converter was operated for extended periods of time with the emitter at about 1900 K, the collector at about 700 K, and a power density of over 2 w(e)/sq cm. Input power transients were run between 50% and 100% thermal power, at up to 1% per second, without instabilities in performance.

  9. Design and Development of a Segmented Magnet Homopolar Torque Converter

    DTIC Science & Technology

    1975-02-01

    IchineVr^V5^ thl ^^^P" concept in large homopolar crLt^ in th^ fi /I蔾’ ^^^C’ a^ electrodynamic power losses created in the fluid during machine...AD-A008 843 DESIGN AND DEVELOPMENT OF A SEGMENTED MAGNET HOMOPOLAR TORQUE CONVERTER C. J. Mole, et al Westinghouse Electric Corporation...This program is for the research and development of a new mechanical power trans- mission concept: the segmented magnet homopolar torque converter

  10. Habitability design elements for a space station

    NASA Technical Reports Server (NTRS)

    Dalton, M. C.

    1983-01-01

    Habitability in space refers to the components, characteristics, conditions, and design parameters that go beyond but include the basic life sustaining requirements. Elements of habitability covered include internal environment, architecture, mobility and restraint, food, clothing, personal hygiene, housekeeping, communications, and crew activities. All elements are interrelated and need to be treated as an overall discipline. Designing for a space station is similar to designing on earth but with 'space rules' instead of ground rules. It is concluded that some habitability problems require behavioral science solutions.

  11. Space Station Freedom solar array design development

    NASA Technical Reports Server (NTRS)

    Winslow, Cindy; Bilger, Kevin; Baraona, Cosmo

    1989-01-01

    The Space Station Freedom solar array program is required to provide a 75-kW power module that uses eight solar array (SA) wings over a four-year period in low earth orbit (LEO). Each wing will be capable of providing 23.4 kW at the 4-yr design point. The design of flexible-substrate SAs that must survive exposure to the space environment, including atomic oxygen, for an operating life of fifteen years is discussed. The tradeoff study and development areas being investigated include solar cell module size, solar cell weld pads, panel stiffener frames, materials inherently resistant to atomic oxygen, and weight reduction design alternatives.

  12. Space Station Freedom photovoltaic power module design status

    NASA Technical Reports Server (NTRS)

    Jimenez, Amador P.; Hoberecht, Mark A.

    1989-01-01

    Electric power generation for Space Station Freedom will be provided by four photovoltaic (PV) power modules using silicon solar cells during Phase 1 operation. Each PV power module requires two solar arrays with 32,800 solar cells generating 18.75 kW of dc power for a total of 75 kW. A portion of this power will be stored in nickel-hydrogen batteries for use during eclipse, and the balance will be processed and converted to 20 kHz ac power for distribution to end users through the power management and distribution system. The design incorporates an optimized thermal control system, pointing and tracking provision with the application of gimbals, and the use of orbital replacement units (ORU's) to achieve modularization. Design status of the PV power module, as derived from major trade studies, is discussed at hardware levels ranging from component to system. Details of the design are presented where appropriate.

  13. Space Station Freedom photovoltaic power module design status

    NASA Technical Reports Server (NTRS)

    Jimenez, Amador P.; Hoberecht, Mark A.

    1989-01-01

    Electric power generation for the Space Station Freedom will be provided by four photovoltaic (PV) power modules using silicon solar cells during phase I operation. Each PV power module requires two solar arrays with 32,800 solar cells generating 18.75 kW of dc power for a total of 75 kW. A portion of this power will be stored in nickel-hydrogen batteries for use during eclipse, and the balance will be processed and converted to 20 kHz ac power for distribution to end users through the power management and distribution system. The design incorporates an optimized thermal control system, pointing and tracking provision with the application of gimbals, and the use of orbital replacement units to achieve modularization. The design status of the PV power module, as derived from major trade studies, is discussed at hardware levels ranging from component to system. Details of the design are presented where appropriate.

  14. Combustor design tool for a gas fired thermophotovoltaic energy converter

    SciTech Connect

    Lindler, K.W.; Harper, M.J.

    1995-07-01

    Recently, there has been a renewed interest in thermophotovoltaic (TPV) energy conversion. A TPV device converts radiant energy from a high temperature incandescent emitter directly into electricity by photovoltaic cells. The current Department of Energy sponsored research involves the design, construction and demonstration of a prototype TPV converter that uses a hydrocarbon fuel (such as natural gas) as the energy source. As the photovoltaic cells are designed to efficiently convert radiant energy at a prescribed wavelength, it is important that the temperature of the emitter be nearly constant over its entire surface. The US Naval Academy has been tasked with the development of a small emitter (with a high emissivity) that can be maintained at 1,756 K (2,700 F). This paper describes the computer spreadsheet model that was developed as a tool to be used for the design of the high temperature emitter.

  15. International space station microgravity environment design & verification

    NASA Astrophysics Data System (ADS)

    Del Basso, Steve

    1999-01-01

    A broad class of scientific experiments has evolved which utilize extreme low acceleration environments. The International Space Station will provide such a ``microgravity'' environment, in conjunction with an unparalleled combination of quiescent period duration, payload volume and power, and manned or telescience interaction. The International Space Station is the world's first manned space vehicle with microgravity requirements. These place limits on the acceleration levels within the pressurized laboratories and affect everything from flight altitude and attitude to the mechanical and acoustic energies emitted by an air circulation fan. To achieve such performance within the program's resource constraints, a microgravity control approach has been adopted which balances both source and receiver disturbance mitigation. The Active Rack Isolation System (ARIS) provides acceleration attenuation at the payload rack level, and dominant sources have been reduced either by isolation or design modifications. Analytical assessments indicate that the vehicle is capable of meeting the challenging microgravity requirements, although some current marginal non-compliances do exist. Assessment refinements will continue through the verification phase with greater reliance on test and on-orbit measured data as part of a long term effort to clearly define and understand the constitution of the acceleration environment. This process will assure that the design and operation of the International Space Station will support significant microgravity science research.

  16. Test and evaluation of load converter topologies used in the Space Station Freedom Power Management and distribution DC test bed

    NASA Technical Reports Server (NTRS)

    Lebron, Ramon C.; Oliver, Angela C.; Bodi, Robert F.

    1991-01-01

    Power components hardware in support of the Space Station Freedom dc Electrical Power System were tested. One type of breadboard hardware tested is the dc Load Converter Unit, which constitutes the power interface between the electric power system and the actual load. These units are dc to dc converters that provide the final system regulation before power is delivered to the load. Three load converters were tested: a series resonant converter, a series inductor switchmode converter, and a switching full-bridge forward converter. The topology, operation principles, and tests results are described, in general. A comparative analysis of the three units is given with respect to efficiency, regulation, short circuit behavior (protection), and transient characteristics.

  17. Test and evaluation of load converter topologies used in the Space Station Freedom power management and distribution dc test bed

    NASA Technical Reports Server (NTRS)

    Lebron, Ramon C.; Oliver, Angela C.; Bodi, Robert F.

    1991-01-01

    Power components hardware in support of the Space Station freedom dc Electric Power System were tested. One type of breadboard hardware tested is the dc Load Converter Unit, which constitutes the power interface between the electric power system and the actual load. These units are dc to dc converters that provide the final system regulation before power is delivered to the load. Three load converters were tested: a series resonant converter, a series inductor switch-mode converter, and a switching full-bridge forward converter. The topology, operation principles, and test results are described, in general. A comparative analysis of the three units is given with respect to efficiency, regulation, short circuit behavior (protection), and transient characteristics.

  18. Radioisotope powered alkali metal thermoelectric converter design for space systems

    NASA Technical Reports Server (NTRS)

    Sievers, R. K.; Bankston, C. P.

    1988-01-01

    The design concept of an alkali-metal thermoelectric converter (AMTEC) for 15-30-percent-efficient conversion of heat from the General Purpose (radioisotope) Heat Source (GPHS) on spacecraft is presented. The basic physical principles of the conversion cycle are outlined; a theoretical model is derived; a modular design is described and illustrated with drawings; and the overall AMTEC/GPHS system design is characterized. Predicted performance data are presented in extensive tables and graphs and discussed in detail.

  19. Design of Compact Multi-Megawatt Mode Converter

    SciTech Connect

    Dolgashev, V.A.; Tantawi, S.G.; Nantista, C.D.; /SLAC

    2006-03-21

    Experience gained during recent operation of high power 11.424 GHz rf sources for accelerators led to new, more strict requirements on system components. One of the basic components of such a system is a mode converter that transforms the rectangular waveguide mode into the TE{sub 01} mode in circular waveguide. With such a converter, it is possible to minimize the use of WR90 rectangular waveguide which was shown to be a weak part of the previous system at power levels higher than 100 MW and pulse lengths on the order of a microsecond. We used several methods to design a mode converter with extremely low parasitic mode conversion and compact size. These methods employ HFSS[4] and include multi-parameter searches, concurrent optimization with a mode-matching code Cascade[2], cascading of resulting S-matrices, and tolerance analysis using perturbation techniques. This report describes the design methods and presents results.

  20. Space station interior design: Results of the NASA/AIA space station interior national design competition

    NASA Technical Reports Server (NTRS)

    Haines, R. F.

    1975-01-01

    The results of the NASA/AIA space station interior national design competition held during 1971 are presented in order to make available to those who work in the architectural, engineering, and interior design fields the results of this design activity in which the interiors of several space shuttle size modules were designed for optimal habitability. Each design entry also includes a final configuration of all modules into a complete space station. A brief history of the competition is presented with the competition guidelines and constraints. The first place award entry is presented in detail, and specific features from other selected designs are discussed. This is followed by a discussion of how some of these design features might be applied to terrestrial as well as space situations.

  1. Aiding Design of Wave Energy Converters via Computational Simulations

    NASA Astrophysics Data System (ADS)

    Jebeli Aqdam, Hejar; Ahmadi, Babak; Raessi, Mehdi; Tootkaboni, Mazdak

    2015-11-01

    With the increasing interest in renewable energy sources, wave energy converters will continue to gain attention as a viable alternative to current electricity production methods. It is therefore crucial to develop computational tools for the design and analysis of wave energy converters. A successful design requires balance between the design performance and cost. Here an analytical solution is used for the approximate analysis of interactions between a flap-type wave energy converter (WEC) and waves. The method is verified using other flow solvers and experimental test cases. Then the model is used in conjunction with a powerful heuristic optimization engine, Charged System Search (CSS) to explore the WEC design space. CSS is inspired by charged particles behavior. It searches the design space by considering candidate answers as charged particles and moving them based on the Coulomb's laws of electrostatics and Newton's laws of motion to find the global optimum. Finally the impacts of changes in different design parameters on the power takeout of the superior WEC designs are investigated. National Science Foundation, CBET-1236462.

  2. Space Station Freedom Solar Array design development

    NASA Technical Reports Server (NTRS)

    Winslow, Cindy; Bilger, Kevin; Baraona, Cosmo R.

    1989-01-01

    The Space Station Freedom Solar Array Program is required to provide a 75 kW power module that uses eight solar array (SA) wings over a four-year period in low Earth orbit (LEO). Each wing will be capable of providing 23.4 kW at the 4-year design point. Lockheed Missles and Space Company, Inc. (LMSC) is providing the flexible substrate SAs that must survive exposure to the space environment, including atomic oxygen, for an operating life of fifteen years. Trade studies and development testing, important for evolving any design to maturity, are presently underway at LMSC on the flexible solar array. The trade study and development areas being investigated include solar cell module size, solar cell weld pads, panel stiffener frames, materials inherently resistant to atomic oxygen, and weight reduction design alternatives.

  3. Design of the LBNF Beamline Target Station

    SciTech Connect

    Tariq, S.; Ammigan, K.; Anderson, K.; Buccellato, S. A.; Crowley, C. F.; Hartsell, B. D.; Hurh, P.; Hylen, J.; Kasper, P.; Krafczyk, G. E.; Lee, A.; Lundberg, B.; Reitzner, S. D.; Sidorov, V.; Stefanik, A. M.; Tropin, I. S.; Vaziri, K.; Williams, K.; Zwaska, R. M.; Densham, C.

    2016-10-01

    The Long Baseline Neutrino Facility (LBNF) project will build a beamline located at Fermilab to create and aim an intense neutrino beam of appropriate energy range toward the DUNE detectors at the SURF facility in Lead, South Dakota. Neutrino production starts in the Target Station, which consists of a solid target, magnetic focusing horns, and the associated sub-systems and shielding infrastructure. Protons hit the target producing mesons which are then focused by the horns into a helium-filled decay pipe where they decay into muons and neutrinos. The target and horns are encased in actively cooled steel and concrete shielding in a chamber called the target chase. The reference design chase is filled with air, but nitrogen and helium are being evaluated as alternatives. A replaceable beam window separates the decay pipe from the target chase. The facility is designed for initial operation at 1.2 MW, with the ability to upgrade to 2.4 MW, and is taking advantage of the experience gained by operating Fermilab’s NuMI facility. We discuss here the design status, associated challenges, and ongoing R&D and physics-driven component optimization of the Target Station.

  4. Design and evaluation of cellular power converter architectures

    NASA Astrophysics Data System (ADS)

    Perreault, David John

    Power electronic technology plays an important role in many energy conversion and storage applications, including machine drives, power supplies, frequency changers and UPS systems. Increases in performance and reductions in cost have been achieved through the development of higher performance power semiconductor devices and integrated control devices with increased functionality. Manufacturing techniques, however, have changed little. High power is typically achieved by paralleling multiple die in a sing!e package, producing the physical equivalent of a single large device. Consequently, both the device package and the converter in which the device is used continue to require large, complex mechanical structures, and relatively sophisticated heat transfer systems. An alternative to this approach is the use of a cellular power converter architecture, which is based upon the parallel connection of a large number of quasi-autonomous converters, called cells, each of which is designed for a fraction of the system rating. The cell rating is chosen such that single-die devices in inexpensive packages can be used, and the cell fabricated with an automated assembly process. The use of quasi-autonomous cells means that system performance is not compromised by the failure of a cell. This thesis explores the design of cellular converter architectures with the objective of achieving improvements in performance, reliability, and cost over conventional converter designs. New approaches are developed and experimentally verified for highly distributed control of cellular converters, including methods for ripple cancellation and current-sharing control. The performance of these techniques are quantified, and their dynamics are analyzed. Cell topologies suitable to the cellular architecture are investigated, and their use for systems in the 5-500 kVA range is explored. The design, construction, and experimental evaluation of a 6 kW cellular switched-mode rectifier is also addressed

  5. Severe Accident Test Station Design Document

    SciTech Connect

    Snead, Mary A.; Yan, Yong; Howell, Michael; Keiser, James R.; Terrani, Kurt A.

    2015-09-01

    The purpose of the ORNL severe accident test station (SATS) is to provide a platform for evaluation of advanced fuels under projected beyond design basis accident (BDBA) conditions. The SATS delivers the capability to map the behavior of advanced fuels concepts under accident scenarios across various temperature and pressure profiles, steam and steam-hydrogen gas mixtures, and thermal shock. The overall facility will include parallel capabilities for examination of fuels and irradiated materials (in-cell) and non-irradiated materials (out-of-cell) at BDBA conditions as well as design basis accident (DBA) or loss of coolant accident (LOCA) conditions. Also, a supporting analytical infrastructure to provide the data-needs for the fuel-modeling components of the Fuel Cycle Research and Development (FCRD) program will be put in place in a parallel manner. This design report contains the information for the first, second and third phases of design and construction of the SATS. The first phase consisted of the design and construction of an out-of-cell BDBA module intended for examination of non-irradiated materials. The second phase of this work was to construct the BDBA in-cell module to test irradiated fuels and materials as well as the module for DBA (i.e. LOCA) testing out-of-cell, The third phase was to build the in-cell DBA module. The details of the design constraints and requirements for the in-cell facility have been closely captured during the deployment of the out-of-cell SATS modules to ensure effective future implementation of the in-cell modules.

  6. Toward systematic design of multi-standard converters

    NASA Astrophysics Data System (ADS)

    Rivas, V. J.; Castro-López, R.; Morgado, A.; Guerra, O.; Roca, E.; del Río, R.; de la Rosa, J. M.; Fernández, F. V.

    2007-05-01

    In the last few years, we are witnessing the convergence of more and more communication capabilities into a single terminal. A basic component of these communication transceivers is the multi-standard Analog-to-Digital-Converter (ADC). Many systematic, partially automated approaches for the design of ADCs dealing with a single communication standard have been reported. However, most multi-standard converters reported in the literature follow an ad-hoc approach, which do not guarantee either an efficient occupation of silicon area or its power efficiency in the different standards. This paper aims at the core of this problem by formulating a systematic design approach based on the following key elements: (1) Definition of a set of metrics for reconfigurability: impact in area and power consumption, design complexity and performances; (2) Definition of the reconfiguration capabilities of the component blocks at different hierarchical levels, with assessment of the associated metrics; (3) Exploration of candidate architectures by using a combination of simulated annealing and evolutionary algorithms; (4) Improved top-down synthesis with bottom-up generated low-level design information. The systematic design methodology is illustrated via the design of a multi-standard ΣΔ modulator meeting the specifications of three wireless communication standards.

  7. International Space Station Crew Restraint Design

    NASA Technical Reports Server (NTRS)

    Whitmore, M.; Norris, L.; Holden, K.

    2005-01-01

    With permanent human presence onboard the International Space Station (ISS), crews will be living and working in microgravity, dealing with the challenges of a weightless environment. In addition, the confined nature of the spacecraft environment results in ergonomic challenges such as limited visibility and access to the activity areas, as well as prolonged periods of unnatural postures. Without optimum restraints, crewmembers may be handicapped for performing some of the on-orbit tasks. Currently, many of the tasks on ISS are performed with the crew restrained merely by hooking their arms or toes around handrails to steady themselves. This is adequate for some tasks, but not all. There have been some reports of discomfort/calluses on the top of the toes. In addition, this type of restraint is simply insufficient for tasks that require a large degree of stability. Glovebox design is a good example of a confined workstation concept requiring stability for successful use. They are widely used in industry, university, and government laboratories, as well as in the space environment, and are known to cause postural limitations and visual restrictions. Although there are numerous guidelines pertaining to ventilation, seals, and glove attachment, most of the data have been gathered in a 1-g environment, or are from studies that were conducted prior to the early 1980 s. Little is known about how best to restrain a crewmember using a glovebox in microgravity. In 2004, The Usability Testing and Analysis Facility (UTAF) at the NASA Johnson Space Center completed development/evaluation of several design concepts for crew restraints to meet the various needs outlined above. Restraints were designed for general purpose use, for teleoperation (Robonaut) and for use with the Life Sciences Glovebox. All design efforts followed a human factors engineering design lifecycle, beginning with identification of requirements followed by an iterative prototype/test cycle. Anthropometric

  8. Zinc Oxide Surge Arresters and HVDC 125kV-upgrade 500kV Converter Stations

    NASA Astrophysics Data System (ADS)

    Shirakawa, Shingo; Kobayashi, Takayuki; Matsushita, Yoshinao; Sakai, Takehisa; Suzuki, Hironori; Ozaki, Yuzo

    Gapless Metal (Zinc) Oxide Surge Arresters for a.c. systems contribute to the insulation co-ordination based on the suppression of lightning surges and switching surges. These gapless metal oxide surge arresters using ZnO elements are effective to HVDC systems. This paper describes basic characteristics of ZnO (zinc oxide) elements for d.c. systems and applications of gapless surge arresters to HVDC 125kV frequency converters, HVDC 250kV, upgrade HVDC 500kV converter stations, and HVDC 500kV cables of Japan through the experience of developments and applications of gapless metal oxide surge arresters.

  9. An approach to design knowledge capture for the space station

    NASA Technical Reports Server (NTRS)

    Wechsler, D. B.; Crouse, K. R.

    1986-01-01

    The design of NASA's space station has begun. During the design cycle, and after activation of the space station, the reoccurring need will exist to access not only designs, but also deeper knowledge about the designs, which is only hinted in the design definition. Areas benefiting from this knowledge include training, fault management, and onboard automation. NASA's Artificial Intelligence Office at Johnson Space Center and The MITRE Corporation have conceptualized an approach for capture and storage of design knowledge.

  10. Transportation node space station conceptual design

    NASA Technical Reports Server (NTRS)

    1988-01-01

    A number of recent studies have addressed the problem of a transportation node space station. How things would change or what addition facilities would be needed to support a major lunar or Mars initiative is a much often asked question. The support of a lunar base, requiring stacks on the order of 200 metric tons each to land 25 m tons on the lunar surface with reusable vehicles is addressed. The problem of maintaining and reusing large single stage Orbit Transfer Vehicles (OTVs) and single stage lander/launchers in space are examined. The required people and equipment needed, to maintain these vehicles are only vaguely known at present. The people and equipment needed depend on how well the OTV and lander/launcher can be designed for easy reuse. Since the OTV and lander/launcher are only conceptually defined at present, the real maintenance and refurbishment requirements are unobtainable. An estimate of what is needed, based on previous studies and obvious requirements was therefore made. An attempt was made to err on the conservative side.

  11. FDMA system design and analysis for Space Station

    NASA Technical Reports Server (NTRS)

    Tsang, Chit-Sang; Chie, Chak-Ming; Ratliff, James E.

    1986-01-01

    Space Station FDMA communications system requirements, design, and analysis are addressed. The analysis is primarily based on numerical results generated by a computer simulation system called SCSS. The time-line communications performance during real time mission operation is also discussed. The purpose of this paper is three-fold: introduction to Space Station multiple access communications system requirements, demonstration of system analysis by a computer tool, and design of an FDMA communications system for the Space Station.

  12. A design optimization process for Space Station Freedom

    NASA Technical Reports Server (NTRS)

    Chamberlain, Robert G.; Fox, George; Duquette, William H.

    1990-01-01

    The Space Station Freedom Program is used to develop and implement a process for design optimization. Because the relative worth of arbitrary design concepts cannot be assessed directly, comparisons must be based on designs that provide the same performance from the point of view of station users; such designs can be compared in terms of life cycle cost. Since the technology required to produce a space station is widely dispersed, a decentralized optimization process is essential. A formulation of the optimization process is provided and the mathematical models designed to facilitate its implementation are described.

  13. Apollo experience report: Crew station integration. Volume 1: Crew station design and development

    NASA Technical Reports Server (NTRS)

    Allen, L. D.; Nussman, D. A.

    1976-01-01

    An overview of the evolution of the design and development of the Apollo command module and lunar module crew stations is given, with emphasis placed on the period from 1964 to 1969. The organizational planning, engineering techniques, and documentation involved are described, and a detailed chronology of the meetings, reviews, and exercises is presented. Crew station anomalies for the Apollo 7 to 11 missions are discussed, and recommendations for the solution of recurring problems of crew station acoustics, instrument glass failure, and caution and warning system performance are presented. Photographs of the various crew station configurations are also provided.

  14. Converting Limbo Lands to Energy-Generating Stations: Renewable Energy Technologies on Underused, Formerly Contaminated Sites

    SciTech Connect

    Mosey, G.; Heimiller, D.; Dahle, D.; Vimmerstedt, L.; Brady-Sabeff, L.

    2007-10-01

    This report addresses the potential for using 'Limbo Lands' (underused, formerly contaminated sites, landfills, brownfields, abandoned mine lands, etc. ) as sites for renewable energy generating stations.

  15. Design of a Multiple-Input SC DC-DC Converter Realizing Long Battery Runtime

    NASA Astrophysics Data System (ADS)

    Eguchi, Kei; Pongswatd, Sawai; Julsereewong, Amphawan; Tirasesth, Kitti; Sasaki, Hirofumi; Inoue, Takahiro

    A multiple-input switched-capacitor DC-DC converter which can realize long battery runtime is proposed in this letter. Unlike conventional converters for a back-lighting application, the proposed converter drives some LEDs by converting energy from solar cells. Furthermore, the proposed converter can charge a lithium battery when an output load is light. The validity of circuit design is confirmed by theoretical analyses, simulations, and experiments.

  16. Recent developments in HVDC convertor station design

    SciTech Connect

    Carlsson, L.

    1984-08-01

    New requirements on HVDC convertor station performance have emerged during the past few years. The paper presents some of these requirements and shows how they have been met through equipment and system development. This development will result in a new generation of HVDC transmissions with still better performance than for the projects presently in operation.

  17. Design, status and first operations of the spallation neutron source polyphase resonant converter modulator system

    SciTech Connect

    Reass, W. A.; Apgar, S. E.; Baca, D. M.; Doss, James D.; Gonzales, J.; Gribble, R. F.; Hardek, T. W.; Lynch, M. T.; Rees, D. E.; Tallerico, P. J.; Trujillo, P. B.; Anderson, D. E.; Heidenreich, D. A.; Hicks, J. D.; Leontiev, V. N.

    2003-01-01

    The Spallation Neutron Source (SNS) is a new 1.4 MW average power beam, 1 GeV accelerator being built at Oak Ridge National Laboratory. The accelerator requires 15 converter-modulator stations each providing between 9 and 11 MW pulses with up to a 1 .I MW average power. The converter-modulator can be described as a resonant 20 kHz polyphase boost inverter. Each converter modulator derives its buss voltage from a standard substation cast-core transformer. Each substation is followed by an SCR pre-regulator to accommodate voltage changes from no load to full load, in addition to providing a soft-start function. Energy storage is provided by self-clearing metallized hazy polypropylene traction capacitors. These capacitors do not fail short, but clear any internal anomaly. Three 'H-Bridge' IGBT transistor networks are used to generate the polyphase 20 kHz transformer primary drive waveforms. The 20 kHz drive waveforms are time-gated to generate the desired klystron pulse width. Pulse width modulation of the individual 20 lcHz pulses is utilized to provide regulated output waveforms with DSP based adaptive feedforward and feedback techniques. The boost transformer design utilizes nanocrystalline alloy that provides low core loss at design flux levels and switching frequencies. Capacitors are used on the transformer secondary networks to resonate the leakage inductance. The transformers are wound for a specific leakage inductance, not turns ratio. This design technique generates multiple secondary volts per turn as compared to the primary. With the appropriate tuning conditions, switching losses are minimized. The resonant topology has the added benefit of being deQed in a klystron fault condition, with little energy deposited in the arc. This obviates the need of crowbars or other related networks. A review of these design parameters, operational performance, production status, and OWL installation and performance to date will be presented.

  18. Converting Limbo Lands to Energy-Generating Stations: Renewable Energy Technologies on Underused, Formerly Contaminated Sites

    EPA Science Inventory

    This report addresses the potential for using "Limbo Lands" as sites for renewable energy generating stations. Limbo Lands are considered as underused, formerly contaminated sites, and include former Superfund sites, landfills, brownfields, abandoned mine lands, former industrial...

  19. Recommended practice for fire protection for electric generating plants and high voltage direct current converter stations. 2005 ed.

    SciTech Connect

    2005-07-01

    The standard outlines fire safety recommendations for gas, oil, coal, and alternative fuel electric generating plants including high voltage direct current converter stations and combustion turbine units greater than 7500 hp used for electric generation. Provisions apply to both new and existing plants. The document provides fire prevention and fire protection recommendations for the: safety of construction and operating personnel; physical integrity of plant components; and continuity of plant operations. The 2005 edition includes revisions and new art that clarify existing provisions. 5 annexes.

  20. Space Station Freedom power management and distribution system design

    NASA Technical Reports Server (NTRS)

    Teren, Fred

    1989-01-01

    The design is described of the Space Station Freedom Power Management and Distribution (PMAD) System. In addition, the significant trade studies which were conducted are described, which led to the current PMAD system configuration.

  1. Instructor/Operator Station (IOS) Design Guide.

    DTIC Science & Technology

    1988-02-01

    to function as both a remote and an over-the-shoulder station by mounting the instructor seat on tracks, which permit moving to a position close to...re’quiremenrts, and t rainier s;ubsystems associated with it. These dat-a ,h,uild bt, devetloped at, part of the- traininig analys"es. Identi fication of...adjacent to the student (over-the- shoulder) and one at the on-board console for both the IP and IFE. The instruc-tor chairs will be rail- mounted and

  2. Quasi-multi-pulse voltage source converter design with two control degrees of freedom

    NASA Astrophysics Data System (ADS)

    Vural, A. M.; Bayindir, K. C.

    2015-05-01

    In this article, the design details of a quasi-multi-pulse voltage source converter (VSC) switched at line frequency of 50 Hz are given in a step-by-step process. The proposed converter is comprised of four 12-pulse converter units, which is suitable for the simulation of single-/multi-converter flexible alternating current transmission system devices as well as high voltage direct current systems operating at the transmission level. The magnetic interface of the converter is originally designed with given all parameters for 100 MVA operation. The so-called two-angle control method is adopted to control the voltage magnitude and the phase angle of the converter independently. PSCAD simulation results verify both four-quadrant converter operation and closed-loop control of the converter operated as static synchronous compensator (STATCOM).

  3. Water vent design for Space Station Freedom

    NASA Astrophysics Data System (ADS)

    Miernik, Janie H.; Worden, Edson A.; Bedard, John E.; Lieu, Bing H.

    1992-07-01

    Space Stadon Freedom (SSF) will be required to vent water during non-quiescent periods. During Man Tended Configuration (MTC), before the Environmental Control and Life Support System (ECLSS) water loop is closed, humidity condensate will be periodically vented. At Permanently Manned Configuration (PMC), water will be vented on contingency if there is excess water on SSF. The thrust due to venting must be minimized to be considered non-propulsive. Also, ice formation and clogging of the vent nozzle must be avoided. Many aspects of the Space Shuttle water vent design were utilized in development of the preliminary SSF water vent design presented in this paper. Design modifications which improved the shuttle vent as well as those necessary for SSF are discussed. The exterior vent location, direction and environment on SSF are unique compared to previous space water vent designs. From data collected in the vent tests and analyses, a finalized SSF water vent design will be developed.

  4. Genesis Halo Orbit Station Keeping Design

    NASA Technical Reports Server (NTRS)

    Lo, M.; Williams, K.; Wilson, R.; Howell, K.; Barden, B.

    2000-01-01

    As the fifth mission of NASA's Directory Program, Genesis is designed to collect solar wind samples for approximately two years in a halo orbit near the Sun-Earth L(sub 1) Lagrange point for return to the Earth.

  5. Hybrid Rocket Experiment Station for Capstone Design

    NASA Technical Reports Server (NTRS)

    Conley, Edgar; Hull, Bethanne J.

    2012-01-01

    Portable hybrid rocket motors and test stands can be seen in many papers but none have been reported on the design or instrumentation at such a small magnitude. The design of this hybrid rocket and test stand is to be small and portable (suitcase size). This basic apparatus will be used for demonstrations in rocket propulsion. The design had to include all of the needed hardware to operate the hybrid rocket unit (with the exception of the external Oxygen tank). The design of this project includes making the correlation between the rocket's thrust and its size, the appropriate transducers (physical size, resolution, range, and cost), compatability with a laptop analog card, the ease of setup, and its portability.

  6. Design of photovoltaic central power station concentrator array

    SciTech Connect

    Not Available

    1984-02-01

    A design for a photovoltaic central power station using tracking concentrators has been developed. The 100 MW plant is assumed to be located adjacent to the Saguaro Power Station of Arizona Public Service. The design assumes an advanced Martin Marietta two-axis tracking fresnel lens concentrator. The concentrators are arrayed in 5 MW subfields, each with its own power conditioning unit. The photovoltaic plant output is connected to the existing 115 kV switchyard. The site specific design allows detailed cost estimates for engineering, site preparation, and installation. Collector and power conditioning costs have been treated parametrically.

  7. Dynamic Performance of a Back-to-Back HVDC Station Based on Voltage Source Converters

    NASA Astrophysics Data System (ADS)

    Khatir, Mohamed; Zidi, Sid-Ahmed; Hadjeri, Samir; Fellah, Mohammed-Karim

    2010-01-01

    The recent developments in semiconductors and control equipment have made the voltage source converter based high voltage direct current (VSC-HVDC) feasible. This new DC transmission is known as "HVDC Light or "HVDC Plus by leading vendors. Due to the use of VSC technology and pulse width modulation (PWM) the VSC-HVDC has a number of potential advantages as compared with classic HVDC. In this paper, the scenario of back-to-back VSC-HVDC link connecting two adjacent asynchronous AC networks is studied. Control strategy is implemented and its dynamic performances during disturbances are investigated in MATLAB/Simulink program. The simulation results have shown good performance of the proposed system under balanced and unbalanced fault conditions.

  8. Space station electric power system requirements and design

    NASA Technical Reports Server (NTRS)

    Teren, Fred

    1987-01-01

    An overview of the conceptual definition and design of the space station Electric Power System (EPS) is given. Responsibilities for the design and development of the EPS are defined. The EPS requirements are listed and discussed, including average and peak power requirements, contingency requirements, and fault tolerance. The most significant Phase B trade study results are summarized, and the design selections and rationale are given. Finally, the power management and distribution system architecture is presented.

  9. Space Station electric power system requirements and design

    NASA Technical Reports Server (NTRS)

    Teren, Fred

    1987-01-01

    An overview of the conceptual definition and design of the Space Station Electric Power System (EPS) is given. Responsibilities for the design and development of the EPS are defined. The EPS requirements are listed and discussed, including average and peak power requirements, contingency requirements, and fault tolerance. The most significant Phase B trade study results are summarized, and the design selections and rationale are given. Finally, the power management and distribution system architecture is presented.

  10. Integrated Station Executive requirements and systems design approach

    NASA Technical Reports Server (NTRS)

    Berger, Eugene L.; Morris, C. Doug

    1992-01-01

    The Avionics Office of the Space Station Projects Office at Johnson Space Center (JSC) is working to define and integrate end-to-end requirements for the Space Station Freedom Program (SSFP) space-ground operations. As part of these efforts, the project office has had the MITRE Corporation perform assessments and analyses in areas where they had particular concern. These areas include the changing concepts for test methodologies, the operation and performance of the communication protocols, end-to-end network management, and the Master Objects Data Base (MODB). Since the recent restructure of the space station design, a new software application, the Integrated Station Executive (ISE), has been established. This application is to act as an executive agent along with the crew and ground controllers, while replacing (or absorbing) many of the system management functions that required a home when distributed element management was eliminated. This document summarizes the current state of the ISE requirements and assesses the characteristics of the current design. MITRE's goals in this assessment and analysis is twofold: first, identify any internal inconsistencies in either the requirements or in the current design; and second, to examine the applicability of the Open System Interconnection (OSI) management standards. Inasmuch as the ISE has been defined as the executive or operations manager application within the integrated avionics of the space station, special attention is given to adapting OSI management for the specification of the ISE functions.

  11. Space Station Freedom pressurized element interior design process

    NASA Technical Reports Server (NTRS)

    Hopson, George D.; Aaron, John; Grant, Richard L.

    1990-01-01

    The process used to develop the on-orbit working and living environment of the Space Station Freedom has some very unique constraints and conditions to satisfy. The goal is to provide maximum efficiency and utilization of the available space, in on-orbit, zero G conditions that establishes a comfortable, productive, and safe working environment for the crew. The Space Station Freedom on-orbit living and working space can be divided into support for three major functions: (1) operations, maintenance, and management of the station; (2) conduct of experiments, both directly in the laboratories and remotely for experiments outside the pressurized environment; and (3) crew related functions for food preparation, housekeeping, storage, personal hygiene, health maintenance, zero G environment conditioning, and individual privacy, and rest. The process used to implement these functions, the major requirements driving the design, unique considerations and constraints that influence the design, and summaries of the analysis performed to establish the current configurations are described. Sketches and pictures showing the layout and internal arrangement of the Nodes, U.S. Laboratory and Habitation modules identify the current design relationships of the common and unique station housekeeping subsystems. The crew facilities, work stations, food preparation and eating areas (galley and wardroom), and exercise/health maintenance configurations, waste management and personal hygiene area configuration are shown. U.S. Laboratory experiment facilities and maintenance work areas planned to support the wide variety and mixtures of life science and materials processing payloads are described.

  12. Design of a Base Station for MEMS CCR Localization in an Optical Sensor Network

    PubMed Central

    Park, Chan Gook; Jeon, Hyun Cheol; Kim, Hyoun Jin; Kim, Jae Yoon

    2014-01-01

    This paper introduces a design and implementation of a base station, capable of positioning sensor nodes using an optical scheme. The base station consists of a pulse laser module, optical detectors and beam splitter, which are mounted on a rotation-stage, and a Time to Digital Converter (TDC). The optical pulse signal transmitted to the sensor node with a Corner Cube Retro-reflector (CCR) is reflected to the base station, and the Time of Flight (ToF) data can be obtained from the two detectors. With the angle and flight time data, the position of the sensor node can be calculated. The performance of the system is evaluated by using a commercial CCR. The sensor nodes are placed at different angles from the base station and scanned using the laser. We analyze the node position error caused by the rotation and propose error compensation methods, namely the outlier sample exception and decreasing the confidence factor steadily using the recursive least square (RLS) methods. Based on the commercial CCR results, the MEMS CCR is also tested to demonstrate the compatibility between the base station and the proposed methods. The result shows that the localization performance of the system can be enhanced with the proposed compensation method using the MEMS CCR. PMID:24815681

  13. Design of a base station for MEMS CCR localization in an optical sensor network.

    PubMed

    Park, Chan Gook; Jeon, Hyun Cheol; Kim, Hyoun Jin; Kim, Jae Yoon

    2014-05-08

    This paper introduces a design and implementation of a base station, capable of positioning sensor nodes using an optical scheme. The base station consists of a pulse laser module, optical detectors and beam splitter, which are mounted on a rotation-stage, and a Time to Digital Converter (TDC). The optical pulse signal transmitted to the sensor node with a Corner Cube Retro-reflector (CCR) is reflected to the base station, and the Time of Flight (ToF) data can be obtained from the two detectors. With the angle and flight time data, the position of the sensor node can be calculated. The performance of the system is evaluated by using a commercial CCR. The sensor nodes are placed at different angles from the base station and scanned using the laser. We analyze the node position error caused by the rotation and propose error compensation methods, namely the outlier sample exception and decreasing the confidence factor steadily using the recursive least square (RLS) methods. Based on the commercial CCR results, the MEMS CCR is also tested to demonstrate the compatibility between the base station and the proposed methods. The result shows that the localization performance of the system can be enhanced with the proposed compensation method using the MEMS CCR.

  14. Space station proximity operations windows: Human factors design guidelines

    NASA Technical Reports Server (NTRS)

    Haines, Richard F.

    1987-01-01

    Proximity operations refers to all activities outside the Space Station which take place within a 1-km radius. Since there will be a large number of different operations involving manned and unmanned vehicles, single- and multiperson crews, automated and manually controlled flight, a wide variety of cargo, and construction/repair activities, accurate and continuous human monitoring of these operations from a specially designed control station on Space Station will be required. Total situational awareness will be required. This paper presents numerous human factors design guidelines and related background information for control windows which will support proximity operations. Separate sections deal with natural and artificial illumination geometry; all basic rendezvous vector approaches; window field-of-view requirements; window size; shape and placement criteria; window optical characteristics as they relate to human perception; maintenance and protection issues; and a comprehensive review of windows installed on U.S. and U.S.S.R. manned vehicles.

  15. Stressing of turbine-generator-exciter shafts by variable-frequency currents superimposed on DC currents in asynchronous HVDC links and following disturbances at converter stations

    SciTech Connect

    Hammons, T.J.; Bremner, J.J. )

    1994-09-01

    Ripple currents on the DC side of both HVDC synchronous and asynchronous. Links together with cleared HVDC and AC system disturbances can excite in some circumstances onerous torsional vibrations in large steam generator shafts. The problem has assumed importance in recent months on account of the HVDC Link between Scotland and Northern Ireland going ahead, on account of the proposed Eire/Wales Link, and because AC/DC/AC couplers are to be installed extensively to interconnect the East and West European Grid Systems. This paper discusses and analyses excitation of shaft torsional vibrations in steam turbine-generator-exciter shafts in close proximity to HVDC converter stations by (1) variable-frequency ripple currents superimposed on the DC currents in asynchronous Links, and (2) disturbances at bi-polar converter stations. The time response and tables show that for the systems studied variable-frequency ripple currents superimposed on the DC current in asynchronous Links can excite shaft torsional vibrations, the very small noncharacteristic currents could result in onerous shaft torques which might damage the machine, and that DC line faults at converter stations in close proximity of steam turbine-generator units can excite onerous turbine-generator shaft torsional response. Detailed simulation of the HVDC converter and generator is necessary for precise assessments of shaft torsional response following HVDC converter station faults. 500MW, 660MW, 1000MW and 1300MW machines are considered in the analyses that are made.

  16. Practical Design Guidelines of qZSI Based Step-Up DC/DC Converter

    NASA Astrophysics Data System (ADS)

    Zakis, Janis; Vinnikov, Dmitri; Roasto, Indrek; Jalakas, Tanel

    2010-01-01

    This paper presents some design guidelines for a new voltage fed step-up DC/DC isolated converter. The most significant advantage of proposed converter is voltage buck-boost operation on single stage. The most promising application for proposed converter is in the field of distributed power generation e.g. fuel cells or photovoltaic. The most sensitive issues - such as power losses caused by high currents in the input side of converter and high transient overvoltages across the inverter bridge caused by stray inductances were discussed and solved. The proposals and recommendations to overcome these issues are given in the paper. The Selection and design guidelines of converter elements are proposed and explained. The prototype of proposed converter was built and experimentally tested. Some results are presented and evaluated.

  17. 49 CFR 192.163 - Compressor stations: Design and construction.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Compressor stations: Design and construction. 192.163 Section 192.163 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION OF NATURAL AND OTHER GAS...

  18. A practical design for an integrated HVDC unit - connected hydro-electric generating station

    SciTech Connect

    Ingram, L. )

    1988-10-01

    To date, several authors (see reference list) have proclaimed benefits which can be achieved by integrating HVDC converter stations directly with generating units. The cost of a significant amount of plant and facilities found in conventional schemes is thereby eliminated. So far as is known however, no detailed studies have been done to quantify these benefits. This paper outlines the results of a study made recently by the Manitoba HVDC Research Centre to determine the practicality of such a scheme. To give credence to the results an actual hydro station design was used incorporating a HVDC thyristor valve scheme in a hypothetical situation. Financial and other benefits were determined for this example together with conclusions and recommendations for future specific projects and further areas of study.

  19. The space station - An overview of the design process

    NASA Technical Reports Server (NTRS)

    Covington, C.

    1983-01-01

    The design factors being considered in the NASA space-station development program are summarized. The currently envisioned mission requirements are listed, and the system architecture is defined as a core station, mission-dedicated elements, and supporting equipment such as an orbit maneuvering vehicle. System design factors discussed include orbit selection, contamination control, autonomy, system safety, technology implementation, long life, reliability and maintainability, and cost; subsystem design factors include structural considerations, electrical power, environmental control and life support, data management, communications and tracking, onboard propulsion, habitability, and crew support. Configurational design is seen as driven by a number of factors, primarily the need to fit all components into the Shuttle payload bay for assembly in LEO by the Shuttle crew.

  20. The TAHMO project: Designing an unconventional weather station

    NASA Astrophysics Data System (ADS)

    Hut, R. W.; van de Giesen, N. C.; Selker, J. S.

    2012-04-01

    The TAHMO project aims to build a 200 weather station for the African Market. This calls for an out of the box attitude towards design that looks into new and promising technologies and asks "Can this be used for TAHMO?". Already an acoustic rain gauge and a combined thermometer / radiation sensor have been developed. Those will be presented, along with a list of open research / design questions that need enthusiastic students to solve them.

  1. Optimum Design of LLC Resonant Converter using Inductance Ratio (Lm/Lr)

    NASA Astrophysics Data System (ADS)

    Palle, Kowstubha; Krishnaveni, K.; Ramesh Reddy, Kolli

    2016-07-01

    The main benefits of LLC resonant dc/dc converter over conventional series and parallel resonant converters are its light load regulation, less circulating currents, larger bandwidth for zero voltage switching, and less tuning of switching frequency for controlled output. An unique analytical tool, called fundamental harmonic approximation with peak gain adjustment is used for designing the converter. In this paper, an optimum design of the converter is proposed by considering three different design criterions with different values of inductance ratio (Lm/Lr) to achieve good efficiency at high input voltage. The optimum design includes the analysis in operating range, switching frequency range, primary side losses of a switch and stability. The analysis is carried out with simulation using the software tools like MATLAB and PSIM. The performance of the optimized design is demonstrated for a design specification of 12 V, 5 A output operating with an input voltage range of 300-400 V using FSFR 2100 IC of Texas instruments.

  2. Space Station services and design features for users

    NASA Technical Reports Server (NTRS)

    Kurzhals, Peter R.; Mckinney, Royce L.

    1987-01-01

    The operational design features and services planned for the NASA Space Station will furnish, in addition to novel opportunities and facilities, lower costs through interface standardization and automation and faster access by means of computer-aided integration and control processes. By furnishing a basis for large-scale space exploitation, the Space Station will possess industrial production and operational services capabilities that may be used by the private sector for commercial ventures; it could also ultimately support lunar and planetary exploration spacecraft assembly and launch facilities.

  3. Converting Between PLY and Ballistic Research Laboratory-Computer-Aided Design (BRL-CAD) File Formats

    DTIC Science & Technology

    2015-02-01

    Converting Between PLY and Ballistic Research Laboratory–Computer-Aided Design (BRL-CAD) File Formats by Rishub Jain ARL-CR-0760...0760 February 2015 Converting Between PLY and Ballistic Research Laboratory–Computer-Aided Design (BRL-CAD) File Formats Rishub Jain US...and Ballistic Research Laboratory–Computer-Aided Design (BRL-CAD) File Formats 5a. CONTRACT NUMBER W911NF-10-2-0076 5b. GRANT NUMBER 5c. PROGRAM

  4. Antenna design and distribution of the LOFAR super station

    NASA Astrophysics Data System (ADS)

    Girard, Julien N.; Zarka, Philippe; Tagger, Michel; Denis, Laurent; Charrier, Didier; Konovalenko, Alexander A.; Boone, Frédéric

    2012-01-01

    The Nançay radio astronomy observatory and associated laboratories are developing the concept of a "Super Station" for extending the LOFAR station now installed and operational in Nançay. The LOFAR Super Station (LSS) will increase the number of high sensitivity long baselines, provide short baselines, act as an alternate core, and be a large standalone instrument. It will operate in the low frequency band of LOFAR (15-80 MHz) and extend this range to lower frequencies. Three key developments for the LSS are described here: (i) the design of a specific antenna, and the distribution of such antennas; (ii) at small-scale (analog-phased mini-array); and (iii) at large-scale (the whole LSS).

  5. [Principles of design of neural-network analog-to-digital converters of bioelectric signals].

    PubMed

    Loktiukhin, V N; Chelebaev, S V

    2007-01-01

    A design principle and a procedure for synthesis of neural-network analog-to-digital converters of bioelectric signals are suggested. An example of implementation of an FPGA-based neural-network converter for classification of bioparameters is presented.

  6. Preliminary design of the Space Station internal thermal control system

    NASA Technical Reports Server (NTRS)

    Herrin, Mark T.; Patterson, David W.; Turner, Larry D.

    1987-01-01

    The baseline preliminary design configuration of the Internal Thermal Control system (ITCS) of the U.S. Space Station pressurized elements (i.e., the Habitation and U.S. Laboratory modules, pressurized logistics carrier, and resources nodes) is defined. The ITCS is composed of both active and passive components. The subsystems which comprise the ITCS are identified and their functional descriptions are provided. The significant trades and analyses, which were performed during Phase B (i.e., the preliminary design phase) that resulted in the design described herein, are discussed. The ITCS interfaces with the station's central Heat Rejection and Transport System (HRTS), other systems, and externally attached pressurized payloads are described. Requirements on the ITCS with regard to redundancy and experiment support are also addressed.

  7. Table-aided design of the energy-storage reactor in dc-to-dc converters

    NASA Technical Reports Server (NTRS)

    Owen, H. A., Jr.

    1975-01-01

    A new procedure for the selection of magnetic cores for use in energy-storage dc-to-dc power converters which eliminates the need for an automated computer search algorithm and stored data file is presented. The converter configurations included in the procedure are the three commonly encountered single-winding converters for voltage step-up, for current step-up and for voltage step-up/current step-up, and for the two-winding converter for voltage step-up/current step-up. For each converter configuration, three types of controllers are considered - constant-frequency, constant on-time and constant off-time. Using concepts developed from analyses of these converters by considering the transfer of energy by means of an energy-storage inductor or transformer, a special table of parameters calculated from magnetic core data is constructed and leads to a considerably simplified design procedure.

  8. QMI: Rising to the Space Station Design Challenge

    NASA Technical Reports Server (NTRS)

    Carswell, W. E.; Farmer, J.; Coppens, C.; Breeding, S.; Rose, F.; Curreri, Peter A. (Technical Monitor)

    2002-01-01

    The Quench Module Insert (QMI) materials processing furnace is being designed to operate for 8000 hours over four years on the International Space Station (ISS) as part of the first Materials Science Research Rack (MSRR-1) of the Materials Science Research Facility (MSRF). The Bridgman-type furnace is being built for the directional solidification processing of metals and alloys in the microgravity environment of space. Most notably it will be used for processing aluminum and related alloys. Designing for the space station environment presents intriguing design challenges in the form of a ten-year life requirement coupled with both limited opportunities for maintenance and resource constraints in the form of limited power and space. The long life requirement has driven the design of several features in the furnace, including the design of the heater core, the selection and placement of the thermocouples, overall performance monitoring, and the design of the chill block. The power and space limitations have been addressed through a compact furnace design using efficient vacuum insulation. Details on these design features, as well as development test performance results to date, are presented.

  9. Space Station Freedom power management and distribution design status

    NASA Technical Reports Server (NTRS)

    Javidi, S.; Gholdston, E.; Stroh, P.

    1989-01-01

    The design status of the power management and distribution electric power system for the Space Station Freedom is presented. The current design is a star architecture, which has been found to be the best approach for meeting the requirement to deliver 120 V dc to the user interface. The architecture minimizes mass and power losses while improving element-to-element isolation and system flexibility. The design is partitioned into three elements: energy collection, storage and conversion, system protection and distribution, and management and control.

  10. Design of a resistojet for Space Station Freedom

    NASA Technical Reports Server (NTRS)

    Garza, Jose; Reisman, Jill; Tapia, Jose; Wright, Anthony

    1993-01-01

    In the mid 1990's, NASA will begin assembly of Space Station Freedom, a permanent outpost in a low-earth orbit. For the station to remain in that orbit, an altitude control system must be developed to resist the effects of atmospheric drag. One system being considered by NASA is called a resistojet, and it uses highly pressurized waste gases heated by electrical resistance to provide thrust on the order of 1 Newton. An additional function of the resistojet is to vent waste gases used by the station and its inhabitants. This report focuses on resolving the issues of system performance, flow and heater control, and materials selection and designing test procedures to resolve, by experimentation, any remaining issues. The conceptual model of the resistojet consists of a shell wrapped by a resistive coil with gases flowing internally through the tube with additional components such as regulators, transducers, and thermocouples. For system performance, the major parameters were calculated from the desired thrust range, the pressure within the resistojet and the cold flow mode of operation; waste gases were analyzed at 100 percent capacity and between 58.95 kPa and 552 kPa. The design team found that any ventilation under all conditions would produce thrust, and therefore, it was decided to limit the design of the ventilation function. The design team proceeded with a simplified model to determine the nozzle throat diameter and chamber diameter.

  11. Project EGRESS: Earthbound Guaranteed Reentry from Space Station. the Design of an Assured Crew Recovery Vehicle for the Space Station

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Unlike previously designed space-based working environments, the shuttle orbiter servicing the space station will not remain docked the entire time the station is occupied. While an Apollo capsule was permanently available on Skylab, plans for Space Station Freedom call for a shuttle orbiter to be docked at the space station for no more than two weeks four times each year. Consideration of crew safety inspired the design of an Assured Crew Recovery Vehicle (ACRV). A conceptual design of an ACRV was developed. The system allows the escape of one or more crew members from Space Station Freedom in case of emergency. The design of the vehicle addresses propulsion, orbital operations, reentry, landing and recovery, power and communication, and life support. In light of recent modifications in space station design, Project EGRESS (Earthbound Guaranteed ReEntry from Space Station) pays particular attention to its impact on space station operations, interfaces and docking facilities, and maintenance needs. A water-landing medium-lift vehicle was found to best satisfy project goals of simplicity and cost efficiency without sacrificing safety and reliability requirements. One or more seriously injured crew members could be returned to an earth-based health facility with minimal pilot involvement. Since the craft is capable of returning up to five crew members, two such permanently docked vehicles would allow a full evacuation of the space station. The craft could be constructed entirely with available 1990 technology, and launched aboard a shuttle orbiter.

  12. Space Station Freedom Program preliminary design review process

    NASA Technical Reports Server (NTRS)

    Carlise, R. F.; Adair, Billy

    1989-01-01

    To conduct the Program Requirements Review of the Space Station Freedom, a Preliminary Design Review Board (PDR) has been established. The PDR will assess the preliminary design of the assembled manned base including the assembly process, the launch, and on-orbit stage configuration, the design approach, the on-orbit verification plans, supportability, reliability, safety, interfaces with the NASA infrastructure (the NSTS, TDRSS, and Ground operations) and international partners. Issues such as the coordination of a common interpretation of design requirements, coordination of interfaces, and convergence of design perspectives vs. proper allocation of resources are discussed. The impact of the resolution of the secondary ripple effect of design decisions which may cause programmatic difficulties is also addressed.

  13. Preliminary space station solar array structural design study

    NASA Technical Reports Server (NTRS)

    Dorsey, J. T.; Bush, H. G.; Mikulas, M. M., Jr.

    1984-01-01

    Structurally efficient ways to support the large solar arrays (3,716 square meters which are currently considered for space station use) are examined. An erectable truss concept is presented for the on orbit construction of winged solar arrays. The means for future growth, maintenance, and repair are integrally designed into this concept. Results from parametric studies, which highlight the physical and structural differences between various configuration options are presented. Consideration is given to both solar blanket and hard panel arrays.

  14. Ice Column Design Concept for Summit Station: Laboratory Testing Results

    DTIC Science & Technology

    2013-06-01

    creep rate data to deter- mine whether or not the ice columns produced by this method share those properties (Cole 2012). In any case, a long - term ...would be expected to produce relatively low creep rates of less than 1 m (3.5 ft)/year. Preliminary data suggest that the long - term design pressure...sign Concept features new facilities for long term atmospheric studies at Summit Station, Greenland (Kumin Associates and CH2MHill 2010; Dibb et al

  15. Design of a regenerative fuel cell system for Space Station

    NASA Technical Reports Server (NTRS)

    Hoberecht, M. A.; Rieker, L. L.

    1985-01-01

    The NASA Space Station will employ alkaline regenerative fuel cells (RFCs) as its sole electrochemical energy storage system, in virtue of demonstrated technology readiness and a high degree of system-level design flexibility. NASA Johnson and NASA Lewis are currently engaged in the development of a 10-kW alkaline engineering model system, for 1987 delivery, which will encompass a fully autonomous 120-V system with 55 percent overall electrical efficiency and a 20,000-hr service life.

  16. Space crew productivity: A driving factor in space station design

    NASA Technical Reports Server (NTRS)

    Wolbers, H. L.

    1985-01-01

    The criteria of performance, cost, and mission success probability (program confidence) are the principal factors that program or project managers and system engineers use in selecting the optimum design approach for meeting mission objectives. A frame of reference is discussed in which the interrelationships of these pertinent parameters can be made visible, and from which rational or informed decisions can be derived regarding the potential impact of adjustments in crew productivity on total Space Station System effectiveness.

  17. Design, fabrication, and testing of an external fuel (UO2), full-length thermionic converter

    NASA Technical Reports Server (NTRS)

    Schock, A.; Raab, B.

    1971-01-01

    The development of a full-length external-fuel thermionic converter for in-pile testing is described. The development program includes out-of-pile performance testing of the fully fueled-converter, using RF-induction heating, before its installation in the in-pile test capsule. The external-fuel converter is cylindrical in shape, and consists of an inner, centrally cooled collector, and an outer emitter surrounded by nuclear fuel. The term full-length denotes that the converter is long enough to extend over the full height of the reactor core. Thus, the converter is not a scaled-down test device, but a full-scale fuel element of the thermionic reactor. The external-fuel converter concept permits a number of different design options, particularly with respect to the fuel composition and shape, and the collector cooling arrangement. The converter described was developed for the Jet Propulsion Laboratory, and is based on their concept for a thermionic reactor with uninsulated collector cooling as previously described. The converter is double-ended, with through-flow cooling, and with ceramic seals and emitter and collector power take-offs at both ends. The design uses a revolver-shaped tungsten emitter body, with the central emitter hole surrounded by six peripheral fuel holes loaded with cylindrical UO2 pellets.

  18. Oak Ridge Spallation Neutron Source (ORSNS) target station design integration

    SciTech Connect

    McManamy, T.; Booth, R.; Cleaves, J.; Gabriel, T.

    1996-06-01

    The conceptual design for a 1- to 3-MW short pulse spallation source with a liquid mercury target has been started recently. The design tools and methods being developed to define requirements, integrate the work, and provide early cost guidance will be presented with a summary of the current target station design status. The initial design point was selected with performance and cost estimate projections by a systems code. This code was developed recently using cost estimates from the Brookhaven Pulsed Spallation Neutron Source study and experience from the Advanced Neutron Source Project`s conceptual design. It will be updated and improved as the design develops. Performance was characterized by a simplified figure of merit based on a ratio of neutron production to costs. A work breakdown structure was developed, with simplified systems diagrams used to define interfaces and system responsibilities. A risk assessment method was used to identify potential problems, to identify required research and development (R&D), and to aid contingency development. Preliminary 3-D models of the target station are being used to develop remote maintenance concepts and to estimate costs.

  19. A contribution to the design of fast code converters for position encoders

    NASA Astrophysics Data System (ADS)

    Denic, Dragan B.; Dincic, Milan R.; Miljkovic, Goran S.; Peric, Zoran H.

    2016-10-01

    Pseudorandom binary sequences (PRBS) are very useful in many areas of applications. Absolute position encoders based on PRBS have many advantages. However, the pseudorandom code is not directly applicable to the digital electronic systems, hence a converter from pseudorandom to natural binary code is needed. Recently, a fast pseudorandom/natural code converter based on Galois PRBS generator (much faster than previously used converter based on Fibonacci PRBS generator) was proposed. One of the main parts of the Galois code converter is an initial logic. The problem of the design of the initial logic has been solved only for some single values of resolution, but it is still not solved for any value of resolution, which significantly limits the applicability of the fast Galois code converter. This paper solves this problem presenting the solution for the design of the initial logic of the fast Galois pseudorandom/natural code converters used in the pseudorandom position encoders, in general manner, that is for any value of the resolution, allowing for a wide applicability of the fast Galois pseudorandom position encoders. Rigorous mathematical derivation of the formula for the designing of the initial logic is presented. Simulation of the proposed converter is performed in NI MultiSim software. The proposed solution, although developed for pseudorandom position encoders, can be used in many other fields where PRBS are used.

  20. Verification of Space Station Secondary Power System Stability Using Design of Experiment

    NASA Technical Reports Server (NTRS)

    Karimi, Kamiar J.; Booker, Andrew J.; Mong, Alvin C.; Manners, Bruce

    1998-01-01

    This paper describes analytical methods used in verification of large DC power systems with applications to the International Space Station (ISS). Large DC power systems contain many switching power converters with negative resistor characteristics. The ISS power system presents numerous challenges with respect to system stability such as complex sources and undefined loads. The Space Station program has developed impedance specifications for sources and loads. The overall approach to system stability consists of specific hardware requirements coupled with extensive system analysis and testing. Testing of large complex distributed power systems is not practical due to size and complexity of the system. Computer modeling has been extensively used to develop hardware specifications as well as to identify system configurations for lab testing. The statistical method of Design of Experiments (DoE) is used as an analysis tool for verification of these large systems. DOE reduces the number of computer runs which are necessary to analyze the performance of a complex power system consisting of hundreds of DC/DC converters. DoE also provides valuable information about the effect of changes in system parameters on the performance of the system. DoE provides information about various operating scenarios and identification of the ones with potential for instability. In this paper we will describe how we have used computer modeling to analyze a large DC power system. A brief description of DoE is given. Examples using applications of DoE to analysis and verification of the ISS power system are provided.

  1. Integrated photovoltaic central station conceptual designs. Final report

    SciTech Connect

    Levy, S.L.; Stoddard, L.E.

    1984-06-01

    Conceptual designs are presented for 100 MW photovoltaic central stations using fixed flat plate, one-axis tracking flat plate, two-axis tracking flat plate, and two-axis tracking high concentration collectors. Designs developed were for specific sites in the southwestern and southeastern United States, and were predicated on mid-1990 plant startup. Estimates of system performance and balance-of-system cost were developed, and cost and efficiency requirements for photovoltaic laminates (unframed modules) and concentrator collectors were derived. Results indicate that all four system types appear potentially viable in the Southwest; fixed and one-axis tracking flat plate concepts appear the best alternatives for the Southeast.

  2. A tactical, permanent telemetered volcano monitoring station design

    NASA Astrophysics Data System (ADS)

    Lockhart, A. B.; LaFevers, M.; Couchman, M. R.

    2012-12-01

    The USGS-USAID Volcano Disaster Assistance Program (VDAP) designs, constructs and installs telemetered volcano-monitoring stations for use in developing countries, at a wide range of latitudes and elevations, weather and environmental conditions. The stations typically house seismometers, GPS and webcams, singly or in combination. They are frequently installed quickly during a volcanic crisis, but are expected to function over the long term as permanent stations. The primary design goal is for a simple, highly portable station that can be installed in less than a day, but not require maintenance until the natural end of battery life, usually 2-5 years. The station consists of a pair of aluminum boxes (43x46x71cm, approx.) placed on the ground facing each other, 2-3m apart, forming the lower part of a metal framework made of 2" pipe to mount solar panels and antennae. Vertical sections of 2" pipe, 3-4m long, are clamped to each end of both the boxes, the lower ends buried into cement-filled holes. This makes 4 masts on a rectangular footprint of 1m X 3-4m. Two horizontal crosspieces of 2" pipe 3-4m long are clamped across the masts. Solar panels are laid across the crosspieces, mounted with 2" angle aluminum extending from the high crosspiece to the low one. Relative height of the crosspieces controls the angle of the solar panels. The crosspieces can be lengthened to increase mounting space for additional solar panels. Inside the aluminum boxes, the radios and electronics are housed in plastic boxes. All external cables are protected by flexible aluminum conduit. Important elements of the design include: -Redundant dual solar power supplies of expandable capacity for loads from 1W to 10W or more. -Robust lightning protection afforded by grounded metal footlockers and framework, and a built-in common grounding point. -Strongly resistant to ice loads. -Waterproof, insect-proof plastic boxes for radios and electronics. -Aluminum boxes are easily fabricated, fit within

  3. Using computer graphics to design Space Station Freedom viewing

    NASA Technical Reports Server (NTRS)

    Goldsberry, B. S.; Lippert, B. O.; Mckee, S. D.; Lewis, J. L., Jr.; Mount, F. E.

    1989-01-01

    An important aspect of planning for Space Station Freedom at the United States National Aeronautics and Space Administration (NASA) is the placement of the viewing windows and cameras for optimum crewmember use. Researchers and analysts are evaluating the placement options using a three-dimensional graphics program called PLAID. This program, developed at the NASA Johnson Space Center (JSC), is being used to determine the extent to which the viewing requirements for assembly and operations are being met. A variety of window placement options in specific modules are assessed for accessibility. In addition, window and camera placements are analyzed to insure that viewing areas are not obstructed by the truss assemblies, externally-mounted payloads, or any other station element. Other factors being examined include anthropometric design considerations, workstation interfaces, structural issues, and mechanical elements.

  4. High power density dc/dc converter: Component selection and design

    NASA Technical Reports Server (NTRS)

    Divan, Deepakraj M.

    1989-01-01

    Further work pertaining to design considerations for the new high power, high frequency dc/dc converters is discussed. The goal of the project is the development of high power, high power density dc/dc converters at power levels in the multi-kilowatt to megawatt range for aerospace applications. The prototype converter is rated for 50 kW at a switching frequency of 50 kHz, with an input voltage of 200 Vdc and an output of 2000 Vdc. The overall power density must be in the vicinity of 0.2 to 0.3 kg/kW.

  5. Design and Development of a Segmented Magnet Homopolar Torque Converter

    DTIC Science & Technology

    1975-07-01

    centrifugal, electromagnetic 9. magnetic fluid 10. surface tension - wetted/non-wetted surfaces 11. solidification - thermal, chemical B. Conducting...developing a metallic (liquid metal) magnetic - fluid shaft-seal for large turbine- generators. It was concluded that the magnetic liquid metal...effort and a program of that nature is under consideration. (Design with a con- ductive magnetic fluid must also consider the possibility of

  6. Fire Protection Engineering Design Brief Template. Hydrogen Refueling Station.

    SciTech Connect

    LaFleur, Angela Christine; Muna, Alice Baca; Groth, Katrina M.

    2015-08-01

    Building a hydrogen infrastructure system is critical to supporting the development of alternate- fuel vehicles. This report provides a methodology for implementing a performance-based design of an outdoor hydrogen refueling station that does not meet specific prescriptive requirements in NFPA 2, The Hydrogen Technologies Code . Performance-based designs are a code-compliant alternative to meeting prescriptive requirements. Compliance is demonstrated by comparing a prescriptive-based fueling station design with a performance-based design approach using Quantitative Risk Assessment (QRA) methods and hydrogen risk assessment tools. This template utilizes the Sandia-developed QRA tool, Hydrogen Risk Analysis Models (HyRAM), which combines reduced-order deterministic models that characterize hydrogen release and flame behavior with probabilistic risk models to quantify risk values. Each project is unique and this template is not intended to account for site-specific characteristics. Instead, example content and a methodology are provided for a representative hydrogen refueling site which can be built upon for new hydrogen applications.

  7. Design of Energy Storage Reactors for Dc-To-Dc Converters. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Chen, D. Y.

    1975-01-01

    Two methodical approaches to the design of energy-storage reactors for a group of widely used dc-to-dc converters are presented. One of these approaches is based on a steady-state time-domain analysis of piecewise-linearized circuit models of the converters, while the other approach is based on an analysis of the same circuit models, but from an energy point of view. The design procedure developed from the first approach includes a search through a stored data file of magnetic core characteristics and results in a list of usable reactor designs which meet a particular converter's requirements. Because of the complexity of this procedure, a digital computer usually is used to implement the design algorithm. The second approach, based on a study of the storage and transfer of energy in the magnetic reactors, leads to a straightforward design procedure which can be implemented with hand calculations. An equation to determine the lower-bound volume of workable cores for given converter design specifications is derived. Using this computer lower-bound volume, a comparative evaluation of various converter configurations is presented.

  8. A New Design of Seismic Stations Deployed in South Tyrol

    NASA Astrophysics Data System (ADS)

    Melichar, P.; Horn, N.

    2007-05-01

    When designing the seismic network in South Tyrol, the seismic service of Austria and the Civil defense in South Tyrol combined more that 10 years experience in running seismic networks and private communication systems. In recent years the high data return rate of > 99% and network uptime of > 99.% is achieved by the combination of high quality station design and equipment, and the use of the Antelope data acquisition and processing software which comes with suite of network monitoring & alerting tools including Nagios, etc. The new Data Center is located in city of Bolzano and is connected to the other Data Centers in Austria, Switzerland, and Italy for data back up purposes. Each Data Center uses also redundant communication system if the primary system fails. When designing the South Tyrol network, new improvements were made in seismometer installations, grounding, lighting protection and data communications in order to improve quality of data recorded as well as network up-time, and data return. The new 12 stations are equipped with 6 Channels Q330+PB14f connected to STS2 + EpiSensor sensor. One of the key achievements was made in the grounding concept for the whole seismic station - and aluminum boxes were introduced which delivered Faraday cage isolation. Lightning protection devices are used for the equipment inside the aluminum housing where seismometer and data logger are housed. For the seismometer cables a special shielding was introduced. The broadband seismometer and strong-motion sensor are placed on a thick glass plate and therefore isolated from the ground. The precise seismometer orientation was done by a special groove on the glass plate and in case of a strong earthquake; the seismometer is tide up to the base plate. Temperature stability was achieved by styrofoam sheets inside the seismometer aluminum protection box.

  9. Design Feasibility Study of a Space Station Freedom Truss

    NASA Technical Reports Server (NTRS)

    Armand, Sasan C.; Dohogne, Caroline A.

    1992-01-01

    Here, the focus is on the design and configuration feasibility of the short spacer for the Space Station Program in its launch configuration. The product of this study is being used by Rockwell International (Rocketdyne Division) as they continue their design concept of the current short spacer configuration. It is anticipated that the launch loads will dominate the on-orbit loads and dictate the design configuration of the short spacer. At the present time, the on-orbit loads have not been generated. The structural analysis discussed herein is based on the transient events derived from the Space Transportation System (STS) Interface Control Document (ICD). The transient loading events consist of liftoff loads, landing loads, and emergency landing loads. The quasi-static loading events have been neglected, since the magnitude of the acceleration factors are lower than the transient acceleration factors. The normal mode analyses presented herein are based on the most feasible configurations with acceptable stress ranges.

  10. Design feasibility study of a Space Station Freedom truss

    NASA Astrophysics Data System (ADS)

    Armand, Sasan C.; Dohogne, Caroline A.

    1992-04-01

    Here, the focus is on the design and configuration feasibility of the short spacer for the Space Station Program in its launch configuration. The product of this study is being used by Rockwell International (Rocketdyne Division) as they continue their design concept of the current short spacer configuration. It is anticipated that the launch loads will dominate the on-orbit loads and dictate the design configuration of the short spacer. At the present time, the on-orbit loads have not been generated. The structural analysis discussed herein is based on the transient events derived from the Space Transportation System (STS) Interface Control Document (ICD). The transient loading events consist of liftoff loads, landing loads, and emergency landing loads. The quasi-static loading events have been neglected, since the magnitude of the acceleration factors are lower than the transient acceleration factors. The normal mode analyses presented herein are based on the most feasible configurations with acceptable stress ranges.

  11. Target Station Design for the Mu2e Experiment

    SciTech Connect

    Pronskikh, Vitaly; Ambrosio, Giorgio; Campbell, Michael; Coleman, Richard; Ginther, George; Kashikhin, Vadim; Krempetz, Kurt; Lamm, Michael; Lee, Ang; Leveling, Anthony; Mokhov, Nikolai; Nagaslaev, Vladimir; Stefanik, Andrew; Striganov, Sergei; Werkema, Steven; Bartoszek, Larry; Densham, Chris; Loveridge, Peter; Lynch, Kevin; Popp, James

    2014-07-01

    The Mu2e experiment at Fermilab is devoted to search for the conversion of a negative muon into an electron in the field of a nucleus without emission of neutrinos. One of the main parts of the Mu2e experimental setup is its Target Station in which negative pions are generated in interactions of the 8-GeV primary proton beam with a tungsten target. A large-aperture 5-T superconducting production solenoid (PS) enhances pion collection, and an S-shaped transport solenoid (TS) delivers muons and pions to the Mu2e detector. The heat and radiation shield (HRS) protects the PS and the first TS coils. A beam dump absorbs the spent beam. In order for the PS superconducting magnet to operate reliably the sophisticated HRS was designed and optimized for performance and cost. The beam dump was designed to absorb the spent beam and maintaining its temperature and air activation in the hall at the allowable level. Comprehensive MARS15 simulations have been carried out to optimize all the parts while maximizing muon yield. Results of simulations of critical radiation quantities and their implications on the overall Target Station design and integration will be reported.

  12. Spacecraft Station-Keeping Trajectory and Mission Design Tools

    NASA Technical Reports Server (NTRS)

    Chung, Min-Kun J.

    2009-01-01

    Two tools were developed for designing station-keeping trajectories and estimating delta-v requirements for designing missions to a small body such as a comet or asteroid. This innovation uses NPOPT, a non-sparse, general-purpose sequential quadratic programming (SQP) optimizer and the Two-Level Differential Corrector (T-LDC) in LTool (Libration point mission design Tool) to design three kinds of station-keeping scripts: vertical hovering, horizontal hovering, and orbiting. The T-LDC is used to differentially correct several trajectory legs that join hovering points. In a vertical hovering, the maximum and minimum range points must be connected smoothly while maintaining the spacecrafts range from a small body, all within the law of gravity and the solar radiation pressure. The same is true for a horizontal hover. A PatchPoint is an LTool class that denotes a space-time event with some extra information for differential correction, including a set of constraints to be satisfied by T-LDC. Given a set of PatchPoints, each with its own constraint, the T-LDC differentially corrects the entire trajectory by connecting each trajectory leg joined by PatchPoints while satisfying all specified constraints at the same time. Vertical and horizontal hover both are needed to minimize delta-v spent for station keeping. A Python I/F to NPOPT has been written to be used from an LTool script. In vertical hovering, the spacecraft stays along the line joining the Sun and a small body. An instantaneous delta-v toward the anti- Sun direction is applied at the closest approach to the small body for station keeping. For example, the spacecraft hovers between the minimum range (2 km) point and the maximum range (2.5 km) point from the asteroid 1989ML. Horizontal hovering buys more time for a spacecraft to recover if, for any reason, a planned thrust fails, by returning almost to the initial position after some time later via a near elliptical orbit around the small body. The mapping or

  13. Design and experiment of a cross-shaped mode converter for high-power microwave applications

    SciTech Connect

    Peng, Shengren Yuan, Chengwei; Zhong, Huihuang; Fan, Yuwei

    2013-12-15

    A compact mode converter, which is capable of converting a TM{sub 01} mode into a circularly polarized TE{sub 11} mode, was developed and experimentally studied with high-power microwaves. The converter, consisting of two turnstile junctions, is very short along the wave propagation direction, and therefore is suitable for designing compact and axially aligned high-power microwave radiation systems. In this paper, the principle of a converter working at 1.75 GHz is demonstrated, as well as the experimental results. The experimental and simulation results are in good agreement. At the center frequency, the conversion efficiency is more than 95%, the measured axial ratio is about 0.4 dB, and the power-handing capacity is excess of 1.9 GW.

  14. H2FIRST Reference Station Design Task: Project Deliverable 2-2

    SciTech Connect

    Pratt, Joseph; Terlip, Danny; Ainscough, Chris; Kurtz, Jennifer; Elgowainy, Amgad

    2015-04-20

    This report presents near-term station cost results and discusses cost trends of different station types. It compares various vehicle rollout scenarios and projects realistic near-term station utilization values using the station infrastructure rollout in California as an example. It describes near-term market demands and matches those to cost-effective station concepts. Finally, the report contains detailed designs for five selected stations, which include piping and instrumentation diagrams, bills of materials, and several site-specific layout studies that incorporate the setbacks required by NFPA 2, the National Fire Protection Association Hydrogen Technologies Code. This work identified those setbacks as a significant factor affecting the ability to site a hydrogen station, particularly liquid stations at existing gasoline stations. For all station types, utilization has a large influence on the financial viability of the station.

  15. Conceptual design of the Space Station combustion module

    NASA Technical Reports Server (NTRS)

    Morilak, Daniel P.; Rohn, Dennis W.; Rhatigan, Jennifer L.

    1994-01-01

    The purpose of this paper is to describe the conceptual design of the Combustion Module for the International Space Station Alpha (ISSA). This module is part of the Space Station Fluids/Combustion Facility (SS FCF) under development at the NASA Lewis Research Center. The Fluids/Combustion Facility is one of several science facilities which are being developed to support microgravity science investigations in the US Laboratory Module of the ISSA. The SS FCF will support a multitude of fluids and combustion science investigations over the lifetime of the ISSA and return state-of-the-art science data in a timely and efficient manner to the scientific communities. This will be accomplished through modularization of hardware, with planned, periodic upgrades; modularization of like scientific investigations that make use of common facility functions; and through the use of orbital replacement units (ORU's) for incorporation of new technology and new functionality. The SS FCF is scheduled to become operational on-orbit in 1999. The Combustion Module is presently scheduled for launch to orbit and integration with the Fluids/Combustion Facility in 1999. The objectives of this paper are to describe the history of the Combustion Module concept, the types of combustion science investigations which will be accommodated by the module, the hardware design heritage, the hardware concept, and the hardware breadboarding efforts currently underway.

  16. Conceptual Design of the Space Station Fluids Module

    NASA Technical Reports Server (NTRS)

    Rohn, Dennis W.; Morilak, Daniel P.; Rhatigan, Jennifer L.; Peterson, Todd T.

    1994-01-01

    The purpose of this paper is to describe the conceptual design of the Fluids Module for the International Space Station Alpha (ISSA). This module is part of the Space Station Fluids/Combustion Facility (SS FCF) under development at the NASA Lewis Research Center. The Fluids/Combustion Facility is one of several science facilities which are being developed to support microgravity science investigations in the US Laboratory Module of the ISSA. The SS FCF will support a multitude of fluids and combustion science investigations over the lifetime of the ISSA and return state-of-the-art science data in a timely and efficient manner to the scientific communities. This will be accomplished through modularization of hardware, with planned, periodic upgrades; modularization of like scientific investigations that make use of common facility functions; and use of orbital replacement units (ORU's) for incorporation of new technology and new functionality. Portions of the SS FCF are scheduled to become operational on-orbit in 1999. The Fluids Module is presently scheduled for launch to orbit and integration with the Fluids/Combustion Facility in 2001. The objectives of this paper are to describe the history of the Fluids Module concept, the types of fluids science investigations which will be accommodated by the module, the hardware design heritage, the hardware concept, and the hardware breadboarding efforts currently underway.

  17. Design and performance oof space station photovoltaic radiators

    NASA Technical Reports Server (NTRS)

    White, K. Alan; Fleming, Mike L.; Lee, Avis Y.

    1993-01-01

    The design and performance of the Space Station Freedom Photovoltaic (PV) Power Module Thermal Control System radiators is presented. The PV Radiator is of a single phase pumped loop design using liquid ammonia as the coolant. Key design features are described, including the base structure, deployment mechanism, radiator panels, and two independent coolant loops. The basis for a specific mass of 7.8 kg/sqm is discussed, and methods of lowering this number for future systems are briefly described. Key performance paramters are also addressed. A summary of test results and analysis is presented to illustrate the survivability of the radiator in the micrometeoroid and orbital debris environment. A design criterion of 95% probability of no penetration of both fluid loops over a 10 year period is shown to be met. Methods of increasing the radiator survivability even further are presented. Thermal performance is also discussed, including a comparison of modeling predictions with existing test results. Degradation in thermal performance due to exposure to atomic oxygen and ultraviolet radiation in the low Earth orbit environment is presented. The structural criteria to which the radiator is designed are also briefly addressed. Finally, potential design improvements are discussed.

  18. Design and performance of space station photovoltaic radiators

    SciTech Connect

    White, K.A.; Fleming, M.L.; Lee, A.Y.

    1993-12-31

    The design and performance of the Space Station Freedom Photovoltaic (PV) Power Module Thermal Control System radiators is presented. The PV Radiator is of a single phase pumped loop design using liquid ammonia as the coolant. Key design features are described, including the base structure, deployment mechanism, radiator panels, and two independent coolant loops. The basis for a specific mass of 7.8 kg/sqm is discussed, and methods of lowering this number for future systems are briefly described. Key performance paramters are also addressed. A summary of test results and analysis is presented to illustrate the survivability of the radiator in the micrometeoroid and orbital debris environment. A design criterion of 95% probability of no penetration of both fluid loops over a 10 year period is shown to be met. Methods of increasing the radiator survivability even further are presented. Thermal performance is also discussed, including a comparison of modeling predictions with existing test results. Degradation in thermal performance due to exposure to atomic oxygen and ultraviolet radiation in the low Earth orbit environment is presented. The structural criteria to which the radiator is designed are also briefly addressed. Finally, potential design improvements are discussed.

  19. The environment workbench: A design tool for Space Station Freedom

    NASA Technical Reports Server (NTRS)

    Jongeward, Gary A.; Kuharski, Robert A.; Rankin, Thomas V.; Wilcox, Katherine G.; Roche, James C.

    1991-01-01

    The environment workbench (EWB) is being developed for NASA by S-CUBED to provide a standard tool that can be used by the Space Station Freedom (SSF) design and user community for requirements verification. The desktop tool will predict and analyze the interactions of SSF with its natural and self-generated environments. A brief review of the EWB design and capabilities is presented. Calculations using a prototype EWB of the on-orbit floating potentials and contaminant environment of SSF are also presented. Both the positive and negative grounding configurations for the solar arrays are examined to demonstrate the capability of the EWB to provide quick estimates of environments, interactions, and system effects.

  20. Systems Engineering Design and Technical Analyses for Strategic Avionics Crew Station Design Evaluation Facility (SACDEF)

    DTIC Science & Technology

    1994-05-01

    differs from other older systems in khe lab, it is compatible with current industry standards . The effectiveness of continued maintainability as well as...CFHI branch within the Human Engineering Division is responsible for research addressing crewstation design and areas currently include aircrew...Human Engineering Division, is responsible for research addressing crew station design and aircrew workload for current and future strategic aircraft

  1. Modeling and design of a monolithically integrated power converter on SiC

    NASA Astrophysics Data System (ADS)

    Yu, L. C.; Sheng, K.; Zhao, J. H.

    2008-10-01

    To fully explore the high temperature and high power density potential of the 4H-SiC material, not only power devices need to be fabricated on SiC, but also the circuitries for signal generation/processing, gate driver and control. In this paper, static and dynamic characteristics of SiC lateral JFET (LJFET) devices are numerically simulated and compact circuit models developed. Based on these models, analog and digital integrated circuits functional blocks such as OPAMP, gate driver and logic gates are then designed and simulated. Finally, a fully integrated power converter including pulse-width-modulation circuit, over-temperature protection circuit and a power boost converter is designed and simulated. The converter has an input of 200 V and an output voltage of 400 V, 2.5 A, operating at 1 kW and 5 MHz.

  2. Space station integrated wall design and penetration damage control

    NASA Technical Reports Server (NTRS)

    Coronado, A. R.; Gibbins, M. N.; Wright, M. A.; Stern, P. H.

    1987-01-01

    The analysis code BUMPER executes a numerical solution to the problem of calculating the probability of no penetration (PNP) of a spacecraft subject to man-made orbital debris or meteoroid impact. The codes were developed on a DEC VAX 11/780 computer that uses the Virtual Memory System (VMS) operating system, which is written in FORTRAN 77 with no VAX extensions. To help illustrate the steps involved, a single sample analysis is performed. The example used is the space station reference configuration. The finite element model (FEM) of this configuration is relatively complex but demonstrates many BUMPER features. The computer tools and guidelines are described for constructing a FEM for the space station under consideration. The methods used to analyze the sensitivity of PNP to variations in design, are described. Ways are suggested for developing contour plots of the sensitivity study data. Additional BUMPER analysis examples are provided, including FEMs, command inputs, and data outputs. The mathematical theory used as the basis for the code is described, and illustrates the data flow within the analysis.

  3. Space Station Human Factors: Designing a Human-Robot Interface

    NASA Technical Reports Server (NTRS)

    Rochlis, Jennifer L.; Clarke, John Paul; Goza, S. Michael

    2001-01-01

    The experiments described in this paper are part of a larger joint MIT/NASA research effort and focus on the development of a methodology for designing and evaluating integrated interfaces for highly dexterous and multifunctional telerobot. Specifically, a telerobotic workstation is being designed for an Extravehicular Activity (EVA) anthropomorphic space station telerobot called Robonaut. Previous researchers have designed telerobotic workstations based upon performance of discrete subsets of tasks (for example, peg-in-hole, tracking, etc.) without regard for transitions that operators go through between tasks performed sequentially in the context of larger integrated tasks. The experiments presented here took an integrated approach to describing teleoperator performance and assessed how subjects operating a full-immersion telerobot perform during fine position and gross position tasks. In addition, a Robonaut simulation was also developed as part of this research effort, and experimentally tested against Robonaut itself to determine its utility. Results show that subject performance of teleoperated tasks using both Robonaut and the simulation are virtually identical, with no significant difference between the two. These results indicate that the simulation can be utilized as both a Robonaut training tool, and as a powerful design platform for telepresence displays and aids.

  4. Design and performance of radioisotope space power systems based on OSC multitube AMTEC converter designs

    SciTech Connect

    Schock, A.; Noravian, H.; Or, C.

    1997-12-31

    This paper extends the analytical procedure described in another paper in these proceedings to analyze a variety of compact and light-weight OSC-designed radioisotope-heated generators. Those generators employed General Purpose Heat Source (GPHS) modules and a converter containing sixteen AMTEC cells of OSC`s revised five-tube design with enhanced cell wall reflectivity described in a companion paper in these proceedings. OSC found that the performance of the generator is primarily a function of the thermal insulation between the outside of the generator`s 16 cells and the inside of its wall. After examining a variety of insulation options, it was found that the generator`s performance is optimized by employing a hybrid insulation system, in which the space between the cells is filled with fibrous Min-K insulation, and the generator walls are lined with tapered (i.e., graded-length) multifoil insulation. The OSC design results in a very compact generator, with eight AMTEC cells on each end of the heat source stack. The choice of the five-tube cells makes it possible to expand the BASE tube diameter without increasing the cell diameter. This is important because the eight cells mate well with the stacked GPHS modules. The OSC generator design includes a compliant heat source support and preload arrangement, to hold the heat source modules together during launch, and to maintain thermal contact conductance at the generator`s interfaces despite creep relaxation of its housing. The BOM and EOM (up to 15 years) performances of the revised generators were analyzed for two and three GPHS modules, both for fresh fuel and for aged fuel left over from a spare RTG (Radioisotope Thermoelectric Generator) fueled in 1982. The resulting power outputs were compared with JPL`s latest EOM power demand goals for the Pluto Express and Europa Orbiter missions, and with the generic goals of DOE`s Advanced Radioisotope Power System (ARPS) study. The OSC AMTEC designs yielded system

  5. A 10kW series resonant converter design, transistor characterization, and base-drive optimization

    NASA Technical Reports Server (NTRS)

    Robson, R.; Hancock, D.

    1981-01-01

    Transistors are characterized for use as switches in resonant circuit applications. A base drive circuit to provide the optimal base drive to these transistors under resonant circuit conditions is developed and then used in the design, fabrication and testing of a breadboard, spaceborne type 10 kW series resonant converter.

  6. Conceptual design for the space station Freedom modular combustion facility

    NASA Technical Reports Server (NTRS)

    1989-01-01

    A definition study and conceptual design for a combustion science facility that will be located in the Space Station Freedom's baseline U.S. Laboratory module is being performed. This modular, user-friendly facility, called the Modular Combustion Facility, will be available for use by industry, academic, and government research communities in the mid-1990's. The Facility will support research experiments dealing with the study of combustion and its byproducts. Because of the lack of gravity-induced convection, research into the mechanisms of combustion in the absence of gravity will help to provide a better understanding of the fundamentals of the combustion process. The background, current status, and future activities of the effort are covered.

  7. A LabVIEW-based control system design for PWM converter

    NASA Astrophysics Data System (ADS)

    Ryu, H. S.; Lim, Y. S.; Yoon, K. H.; Lee, J. M.; Kim, Y. C.; Choi, J. H.

    2007-12-01

    This paper presents a new technique of designing a control system for PWM converter based on the LabVIEW and an advanced FPGA reconfigurable embedded control and acquisition equipment, Compact RIO (cRIO). Assuming that a PWM controller is composed in the double loop structure and that the inner loop controller is given, a constructive design system that is able to make data acquisition, modeling, controller design, simulation with PC, and hardware in the loop simulation (HILS) is represented. In this approach, a key point is to obtain an equivalent linear model of the inner loop system including nonlinear components by using the closed loop identification and to use it when the outer loop controller is designed. Experimental results applied to a real PWM converter will be given as a demonstration.

  8. Design of the 50 kW neutron converter for SPIRAL2 facility

    NASA Astrophysics Data System (ADS)

    Avilov, M. S.; Tecchio, L. B.; Titov, A. T.; Tsybulya, V. S.; Zhmurikov, E. I.

    2010-06-01

    SPIRAL2 is a facility for the study of fundamental nuclear physics and multidisciplinary research. SPIRAL2 represents a major advance for research on exotic nuclei. The radioactive ion beam (RIB) production system is comprised of a neutron converter, a target and an ion source. This paper is dedicated to the designing of the 50 kW neutron converter for the SPIRAL2 facility. Among the different variants of the neutron converter, the one based on a rotating solid disk seems quite attractive due to its safety, ease in production and relatively low cost. Dense graphite used as the converter's material allows the production of high-intensity neutron flux and, at the same time, the heat removal from the converter by means of radiation cooling. Thermo-mechanical simulations performed in order to determine the basic geometry and physical characteristics of the neutron production target for SPIRAL2 facility, to define the appropriate beam power distribution, and to predict the target behaviour under the deuteron beam of nominal parameters (40 MeV, 1.2 mA, 50 kW) are presented. To study the main physical and mechanical properties and serviceability under operating conditions, several kinds of graphite have been analyzed and tested. The paper reports the results of such measurements. Radiation damage is the most important issue for the application of graphite as neutron converter. It is well known that the thermal conductivity of the neutron-irradiated graphite is reduced by a factor of 10 from the initial value after irradiation. Difference in volume expansions between the matrix and the fiber results in serious damage of neutron-irradiated C/C composites. Calculations showed that at high temperature the effect of neutron radiation is not so critical and that the change in thermal conductivity does not prevent the use of graphite as neutron converter.

  9. Design, Control, and Modeling of a New Voltage Source Converter for HVDC System

    NASA Astrophysics Data System (ADS)

    Mohan, Madhan; Singh, Bhim; Ketan Panigrahi, Bijaya

    2013-05-01

    Abstract: A New Voltage Source Converter (VSC) based on neutral clamped three-level circuit is proposed for High Voltage DC (HVDC) system. The proposed VSC is designed in a multipulse configuration. The converter is operated by Fundamental Frequency Switching (FFS). A new control method is developed for achieving all the necessary control aspects of HVDC system such as independent real and reactive power control, bidirectional real and reactive power control. The basic of the control method is varying the pulse width and by keeping the dc link voltage constant. The steady state and dynamic performances of HVDC system interconnecting two different frequencies network are demonstrated for active and reactive power control. Total number of transformers used in this system are reduced to half in comparison with the two-level VSCs for both active and reactive power control. The performance of the HVDC system is improved in terms of reduced harmonics level even at fundamental frequency switching. The harmonic performance of the designed converter is also studied for different value of the dead angle (β), and the optimized range of the dead angle is achieved for varying reactive power requirement. Simulation results are presented for the designed three level multipulse voltage source converters with the proposed control algorithm.

  10. Design and real time implementation of single phase boost power factor correction converter.

    PubMed

    Bouafassa, Amar; Rahmani, Lazhar; Mekhilef, Saad

    2015-03-01

    This paper presents a real time implementation of the single-phase power factor correction (PFC) AC-DC boost converter. A combination of higher order sliding mode controller based on super twisting algorithm and predictive control techniques are implemented to improve the performance of the boost converter. Due to the chattering effects, the higher order sliding mode control (HOSMC) is designed. Also, the predictive technique is modified taking into account the large computational delays. The robustness of the controller is verified conducting simulation in MATLAB, the results show good performances in both steady and transient states. An experiment is conducted through a test bench based on dSPACE 1104. The experimental results proved that the proposed controller enhanced the performance of the converter under different parameters variations.

  11. Capacitive power transfer (CPT) system design using a class E resonant converter circuit

    NASA Astrophysics Data System (ADS)

    Kh., Kamarudin; Saat, Shakir; Yusmarnita, Y.; Ramli. M., S.; Sufiah, A. W. Siti

    2016-02-01

    This paper presents a Capacitive Power Transfer (CPT) system design using a Class E resonant converter circuit. The Class E resonant converter circuit is used to produce a high frequency of alternate current. The purpose of this circuit is to transfer the power via capacitive coupling efficiently. A major advantage of Class E resonant converter circuit is low switching losses. To be specifically, the performance of CPT system at 1MHz of operating frequency and 12V of DC supply voltage is analyzed through experimental works. Finally, a prototype of a CPT system is successfully developed which produced 2mW output power through a capacitive plate size is 12cm × 12cm at 0.1cm of air gap distance.

  12. Design and Analysis for a Floating Oscillating Surge Wave Energy Converter: Preprint

    SciTech Connect

    Yu, Y. H.; Li, Y.; Hallett, K.; Hotimsky, C.

    2014-03-01

    This paper presents a recent study on the design and analysis of an oscillating surge wave energy converter. A successful wave energy conversion design requires the balance between the design performance and cost. The cost of energy is often used as the metric to judge the design of the wave energy conversion system. It is often determined based on the device power performance, the cost for manufacturing, deployment, operation and maintenance, as well as the effort to ensure the environmental compliance. The objective of this study is to demonstrate the importance of a cost driven design strategy and how it can affect a WEC design. Three oscillating surge wave energy converter (OSWEC) designs were used as the example. The power generation performance of the design was modeled using a time-domain numerical simulation tool, and the mass properties of the design were determined based on a simple structure analysis. The results of those power performance simulations, the structure analysis and a simple economic assessment were then used to determine the cost-efficiency of selected OSWEC designs. Finally, a discussion on the environmental barrier, integrated design strategy and the key areas that need further investigation is also presented.

  13. Flywheel Energy Storage System Designed for the International Space Station

    NASA Technical Reports Server (NTRS)

    Delventhal, Rex A.

    2002-01-01

    Following successful operation of a developmental flywheel energy storage system in fiscal year 2000, researchers at the NASA Glenn Research Center began developing a flight design of a flywheel system for the International Space Station (ISS). In such an application, a two-flywheel system can replace one of the nickel-hydrogen battery strings in the ISS power system. The development unit, sized at approximately one-eighth the size needed for ISS was run at 60,000 rpm. The design point for the flight unit is a larger composite flywheel, approximately 17 in. long and 13 in. in diameter, running at 53,000 rpm when fully charged. A single flywheel system stores 2.8 kW-hr of useable energy, enough to light a 100-W light bulb for over 24 hr. When housed in an ISS orbital replacement unit, the flywheel would provide energy storage with approximately 3 times the service life of the nickel-hydrogen battery currently in use.

  14. The design of a permanent lunar research station

    NASA Astrophysics Data System (ADS)

    Thomas, James R.

    The advancement of the United States' efforts in space exploration and research requires the establishment of a permanent manned lunar research station. This paper explores the possible design of such a facility. The use of a thin hedratecture dome covering a lunar depression is used to shield three multipurpose buildings and one command and control facility. Provisions for STS shuttle landings and take-off is also explored. The multipurpose buildings are designed using steel framing and cladding. The entire facility, capable of housing a team of thirty, could be transported by one shuttle. The buildings would arrive ready for erection within the completed dome. Steel was selected due to the low cost, high strength to weight ratio, long term durability, ready availability, quality control, and in-place availability of preengineering and fabrication. With the successful installation of the first facility, standardization would lower the already attractive cost for future projects. Facilities of this type could be erected quickly and inexpensively anywhere on the lunar surface.

  15. Structural design feasibility study of Space Station long spacer truss

    NASA Technical Reports Server (NTRS)

    Armand, Sasan C.; Funk, Gregory P.; Dohogne, Caroline A.

    1994-01-01

    The structural design and configuration feasibility of the long spacer truss assembly that will be used as part of the Space Station Freedom is the focus of this study. The structural analysis discussed herein is derived from the transient loading events presented in the Space Transportation System Interface Control Document (STS ICD). The transient loading events are liftoff, landing, and emergency landing loads. Quasi-static loading events were neglected in this study since the magnitude of the quasi-static acceleration factors is lower than that of the transient acceleration factors. Structural analysis of the proposed configuration of the long spacer truss with four longerons indicated that negative safety margins are possible. As a result, configuration changes were proposed. The primary configuration change suggested was to increase the number of truss longerons to six. The six-longeron truss appears to be a more promising structure than the four-longeron truss because it offers a positive margin of safety and more volume in its second bay (BAY2). This additional volume can be used for resupply of some of the orbital replacement units (such as a battery box). Note that the design effort on the long spacer truss has not fully begun and that calculations and reports of the negative safety margins are, to date, based on concept only.

  16. Dual keel Space Station payload pointing system design and analysis feasibility study

    NASA Technical Reports Server (NTRS)

    Smagala, Tom; Class, Brian F.; Bauer, Frank H.; Lebair, Deborah A.

    1988-01-01

    A Space Station attached Payload Pointing System (PPS) has been designed and analyzed. The PPS is responsible for maintaining fixed payload pointing in the presence of disturbance applied to the Space Station. The payload considered in this analysis is the Solar Optical Telescope. System performance is evaluated via digital time simulations by applying various disturbance forces to the Space Station. The PPS meets the Space Station articulated pointing requirement for all disturbances except Shuttle docking and some centrifuge cases.

  17. Resilient design of recharging station networks for electric transportation vehicles

    SciTech Connect

    Kris Villez; Akshya Gupta; Venkat Venkatasubramanian

    2011-08-01

    As societies shift to 'greener' means of transportation using electricity-driven vehicles one critical challenge we face is the creation of a robust and resilient infrastructure of recharging stations. A particular issue here is the optimal location of service stations. In this work, we consider the placement of battery replacing service station in a city network for which the normal traffic flow is known. For such known traffic flow, the service stations are placed such that the expected performance is maximized without changing the traffic flow. This is done for different scenarios in which roads, road junctions and service stations can fail with a given probability. To account for such failure probabilities, the previously developed facility interception model is extended. Results show that service station failures have a minimal impact on the performance following robust placement while road and road junction failures have larger impacts which are not mitigated easily by robust placement.

  18. Design and analysis of a mode B and mode JD satellite Earth station

    NASA Astrophysics Data System (ADS)

    Hance, Dennis J.

    1994-06-01

    This thesis focuses on the design, integration, and analysis of an amateur radio service mode B and mode JD satellite earth station. Preliminary designs were investigated to determine the optimum configuration for the earth station. Modern digital modems, cabling structures, an 80386-based computer system, satellite tracking software, transmission and reception antennas, preamplifiers, and sophisticated performance measurement technologies were integrated into a functioning earth station. Initially, component availability and station design dictated the selection and acquisition of the requisite station equipment, integration of the transmitter, receiver preamplifiers, antennas, and computer equipment followed. Preliminary testing of the various components in the integration station occupied a significant amount of time. Empirical test tracking of different amateur and commercial satellites verified proper operation of the earth station. Results are discussed throughout this thesis.

  19. Engineering design criteria for an image intensifier/image converter camera

    NASA Technical Reports Server (NTRS)

    Sharpsteen, J. T.; Lund, D. L.; Stoap, L. J.; Solheim, C. D.

    1976-01-01

    The design, display, and evaluation of an image intensifier/image converter camera which can be utilized in various requirements of spaceshuttle experiments are described. An image intensifier tube was utilized in combination with two brassboards as power supply and used for evaluation of night photography in the field. Pictures were obtained showing field details which would have been undistinguishable to the naked eye or to an ordinary camera.

  20. Anthracite firing design for central stations: Ignition and emissions aspects

    SciTech Connect

    Garcia-Mallol, J.A.; Kukoski, A.E.; Winkin, J.P.

    1997-12-31

    The most successful technology for firing pulverized anthracite coals in central station steam generators has accumulated more than 12,000 MWe of ordered capacity worldwide, over half of which is already operational. These units burn coals with less than 14% volatile matter. A recent contract is the 2,100 MWe Yangcheng Power Plant, which will fire a southeast Shanxi anthracite having only 5% volatile matter. Foster Wheeler`s technology ensures self-ignition by integrating, in a double-arch fired, water-wall furnace: (1) partial refractory coverage of the walls, (2) venting of cold primary (coal transport) air, (3) hot gas entrainment at the beginning of the jet-flame. Fuel systems applied to anthracite coals will be reviewed, including the one for the ongoing Hanfeng project in Hebei, which consists of two 660 MWe arch-fired units. Alternative means to improve ignition will also be presented. In addition, emissions from anthracites are characterized, including the effect of an over-fire air design suitable for arch-fired furnaces.

  1. International Space Station Crew Quarters Ventilation and Acoustic Design Implementation

    NASA Technical Reports Server (NTRS)

    Broyan, James L., Jr.; Cady, Scott M; Welsh, David A.

    2010-01-01

    The International Space Station (ISS) United States Operational Segment has four permanent rack sized ISS Crew Quarters (CQs) providing a private crew member space. The CQs use Node 2 cabin air for ventilation/thermal cooling, as opposed to conditioned ducted air-from the ISS Common Cabin Air Assembly (CCAA) or the ISS fluid cooling loop. Consequently, CQ can only increase the air flow rate to reduce the temperature delta between the cabin and the CQ interior. However, increasing airflow causes increased acoustic noise so efficient airflow distribution is an important design parameter. The CQ utilized a two fan push-pull configuration to ensure fresh air at the crew member's head position and reduce acoustic exposure. The CQ ventilation ducts are conduits to the louder Node 2 cabin aisle way which required significant acoustic mitigation controls. The CQ interior needs to be below noise criteria curve 40 (NC-40). The design implementation of the CQ ventilation system and acoustic mitigation are very inter-related and require consideration of crew comfort balanced with use of interior habitable volume, accommodation of fan failures, and possible crew uses that impact ventilation and acoustic performance. Each CQ required 13% of its total volume and approximately 6% of its total mass to reduce acoustic noise. This paper illustrates the types of model analysis, assumptions, vehicle interactions, and trade-offs required for CQ ventilation and acoustics. Additionally, on-orbit ventilation system performance and initial crew feedback is presented. This approach is applicable to any private enclosed space that the crew will occupy.

  2. Analysis and Design of Crew Sleep Station for ISS

    NASA Technical Reports Server (NTRS)

    Keener, John F.; Paul, Thomas; Eckhardt, Bradley; Smith, Fredrick

    2002-01-01

    This paper details the analysis and design of the Temporary Sleep Station (TeSS) environmental control system for International Space Station (ISS). The TeSS will provide crewmembers with a private and personal space, to accommodate sleeping, donning and doffing of clothing, personal communication and performance of recreational activities. The need for privacy to accommodate these activities requires adequate ventilation inside the TeSS. This study considers whether temperature, carbon dioxide, and humidity within the TeSS remain within crew comfort and safety levels for various expected operating scenarios. Evaluation of these scenarios required the use and integration of various simulation codes. An approach was adapted for this study, whereby results from a particular code were integrated with other codes when necessary. Computational Fluid Dynamics (CFD) methods were used to evaluate the flow field inside the TeSS, from which local gradients for temperature, velocity, and species concentration such as CO (sub 2) could be determined. A model of the TeSS, containing a human, as well as equipment such as a laptop computer, was developed in FLUENT, a finite-volume code. Other factors, such as detailed analysis of the heat transfer through the structure, radiation, and air circulation from the TeSS to the US Laboratory Aisle, where the TeSS is housed, were considered in the model. A complementary model was developed in G189A, a code which has been used by NASA/JSC for environmental control systems analyses since the Apollo program. Boundary conditions were exchanged between the FLUENT and G189A TeSS models. G189A provides human respiration rates to the FLUENT model, while the FLUENT model provides local convective heat transfer coefficients to G189A model. An additional benefit from using an approach with both a systems simulation and CFD model, is the capability to verify the results of each model by comparison to the results of the other model. The G189A and

  3. Design automation techniques for high-resolution current folding and interpolating CMOS A/D converters

    NASA Astrophysics Data System (ADS)

    Gevaert, D.

    2007-05-01

    The design and testing of a 12-bit Analog-to-Digital (A/D) converter, in current mode, arranged in an 8-bit LSB and a 4- bit MSB architecture together with the integration of specialized test building blocks on chip allows the set up of a design automation technique for current folding and interpolation CMOS A/D converter architectures. The presented design methodology focuses on the automation for CMOS A/D building blocks in a flexible target current folding and interpolating architecture for a downscaling technology and for different quality specifications. The comprehensive understanding of all sources of mismatching in the crucial building blocks and the use of physical based mismatch modeling in the prediction of mismatch errors, more adequate and realistic sizing of all transistors will result in an overall area reduction of the A/D converter. In this design the folding degree is 16, the number of folders is 64 and the interpolation level is 4. The number of folders is reduced by creating intermediate folding signals with a 4-level interpolator based on current division techniques. Current comparators detect the zero-crossing between the differential folder output currents. The outputs of the comparators deliver a cyclic thermometer code. The digital synthesis part for decoding and error correction building blocks is a standardized digital standard cell design. The basic building blocks in the target architecture were designed in 0.35μ CMOS technology; they are suitable for topological reuse and are in an automated way downscaled into a 0.18μ CMOS technology.

  4. The hydraulic design of pump turbine for Xianyou pumped storage power station

    NASA Astrophysics Data System (ADS)

    Zheng, J. S.; Liu, W. C.; Fu, Z. Y.; Shi, Q. H.

    2012-11-01

    This paper presents the hydraulic design of pump turbines for Xianyou pumped storage power station. The method of improving the hydraulic performance of pump turbine with CFD analysis is given. The results of model test indicate that the final hydraulic design of pump turbine for Xianyou pumped storage power station is of high efficiencies, good

  5. 49 CFR 192.163 - Compressor stations: Design and construction.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... which can be readily opened from the inside without a key. Each swinging door located in an exterior wall must be mounted to swing outward. (d) Fenced areas. Each fence around a compressor station...

  6. Design and simulation of a fast-charging station for plug-in hybrid electric vehicle (PHEV) batteries

    NASA Astrophysics Data System (ADS)

    de Leon, Nathalie Pulmones

    2011-12-01

    With the increasing interest in green technologies in transportation, plug-in hybrid electric vehicles (PHEV) have proven to be the best short-term solution to minimize greenhouse gas emissions. Despite such interest, conventional vehicle drivers are still reluctant in using such a new technology, mainly because of the long duration (4-8 hours) required to charge PHEV batteries with the currently existing Level I and II chargers. For this reason, Level III fast-charging stations capable of reducing the charging duration to 10-15 minutes are being considered. The present thesis focuses on the design of a fast-charging station that uses, in addition to the electrical grid, two stationary energy storage devices: a flywheel energy storage and a supercapacitor. The power electronic converters used for the interface of the energy sources with the charging station are designed. The design also focuses on the energy management that will minimize the PHEV battery charging duration as well as the duration required to recharge the energy storage devices. For this reason, an algorithm that minimizes durations along with its mathematical formulation is proposed, and its application in fast charging environment will be illustrated by means of two scenarios.

  7. Thermal Dissipation Modelling and Design of ITER PF Converter Alternating Current Busbar

    NASA Astrophysics Data System (ADS)

    Guo, Bin; Song, Zhiquan; Fu, Peng; Jiang, Li; Li, Jinchao; Wang, Min; Dong, Lin

    2016-10-01

    Because the larger metallic surrounds are heated by the eddy current, which is generated by the AC current flowing through the AC busbar in the International Thermonuclear Experimental Reactor (ITER) poloidal field (PF) converter system, shielding of the AC busbar is required to decrease the temperature rise of the surrounds to satisfy the design requirement. Three special types of AC busbar with natural cooling, air cooling and water cooling busbar structure have been proposed and investigated in this paper. For each cooling scheme, a 3D finite model based on the proposed structure has been developed to perform the electromagnetic and thermal analysis to predict their operation behavior. Comparing the analysis results of the three different cooling patterns, water cooling has more advantages than the other patterns and it is selected to be the thermal dissipation pattern for the AC busbar of ITER PF converter unit. The approach to qualify the suitable cooling scheme in this paper can be provided as a reference on the thermal dissipation design of AC busbar in the converter system. supported by National Natural Science Foundation of China (No. 51407179)

  8. Using computer graphics to design Space Station Freedom viewing

    NASA Technical Reports Server (NTRS)

    Goldsberry, Betty S.; Lippert, Buddy O.; Mckee, Sandra D.; Lewis, James L., Jr.; Mount, Francis E.

    1993-01-01

    Viewing requirements were identified early in the Space Station Freedom program for both direct viewing via windows and indirect viewing via cameras and closed-circuit television (CCTV). These requirements reside in NASA Program Definition and Requirements Document (PDRD), Section 3: Space Station Systems Requirements. Currently, analyses are addressing the feasibility of direct and indirect viewing. The goal of these analyses is to determine the optimum locations for the windows, cameras, and CCTV's in order to meet established requirements, to adequately support space station assembly, and to operate on-board equipment. PLAID, a three-dimensional computer graphics program developed at NASA JSC, was selected for use as the major tool in these analyses. PLAID provides the capability to simulate the assembly of the station as well as to examine operations as the station evolves. This program has been used successfully as a tool to analyze general viewing conditions for many Space Shuttle elements and can be used for virtually all Space Station components. Additionally, PLAID provides the ability to integrate an anthropometric scale-modeled human (representing a crew member) with interior and exterior architecture.

  9. Design of a high efficiency 30 kW boost composite converter

    SciTech Connect

    Kim, Hyeokjin; Chen, Hua; Maksimovic, Dragan; Erickson, Robert W.

    2015-09-20

    An experimental 30 kW boost composite converter is described in this paper. The composite converter architecture, which consists of a buck module, a boost module, and a dual active bridge module that operates as a DC transformer (DCX), leads to substantial reductions in losses at partial power points, and to significant improvements in weighted efficiency in applications that require wide variations in power and conversion ratio. A comprehensive loss model is developed, accounting for semiconductor conduction and switching losses, capacitor losses, as well as dc and ac losses in magnetic components. Based on the developed loss model, the module and system designs are optimized to maximize efficiency at a 50% power point. Experimental results for the 30 kW prototype demonstrate 98.5%peak efficiency, very high efficiency over wide ranges of power and voltage conversion ratios, as well as excellent agreements between model predictions and measured efficiency curves.

  10. Crew Restraint Design for the International Space Station

    NASA Technical Reports Server (NTRS)

    Norris, Lena; Holden, Kritina; Whitmore, Mihriban

    2006-01-01

    With permanent human presence onboard the International Space Station (ISS), crews will be living and working in microgravity, dealing with the challenges of a weightless environment. In addition, the confined nature of the spacecraft environment results in ergonomic challenges such as limited visibility and access to the activity areas, as well as prolonged periods of unnatural postures. Without optimum restraints, crewmembers may be handicapped for performing some of the on-orbit tasks. Currently, many of the tasks on ISS are performed with the crew restrained merely by hooking their arms or toes around handrails to steady themselves. This is adequate for some tasks, but not all. There have been some reports of discomfort/calluses on the top of the toes. In addition, this type of restraint is simply insufficient for tasks that require a large degree of stability. Glovebox design is a good example of a confined workstation concept requiring stability for successful use. They are widely used in industry, university, and government laboratories, as well as in the space environment, and are known to cause postural limitations and visual restrictions. Although there are numerous guidelines pertaining to ventilation, seals, and glove attachment, most of the data have been gathered in a 1-g environment, or are from studies that were conducted prior to the early 1980 s. Little is known about how best to restrain a crewmember using a glovebox in microgravity. Another ISS task that requires special consideration with respect to restraints is robotic teleoperation. The Robot Systems Technology Branch at the NASA Johnson Space Center is developing a humanoid robot astronaut, or Robonaut. It is being designed to perform extravehicular activities (EVAs) in the hazardous environment of space. An astronaut located inside the ISS will remotely operate Robonaut through a telepresence control system. Essentially, the robot mimics every move the operator makes. This requires the

  11. Incorporation of privacy elements in space station design

    NASA Technical Reports Server (NTRS)

    Harrison, Albert A.; Caldwell, Barrett; Struthers, Nancy J.

    1988-01-01

    Privacy exists to the extent that individuals can control the degree of social contact that they have with one another. The opportunity to withdraw from other people serves a number of important psychological and social functions, and is in the interests of safety, high performance, and high quality of human life. Privacy requirements for Space Station crew members are reviewed, and architectual and other guidelines for helping astronauts achieve desired levels of privacy are suggested. In turn, four dimensions of privacy are discussed: the separation of activities by areas within the Space Station, controlling the extent to which astronauts have visual contact with one another, controlling the extent to which astronauts have auditory contact with one another, and odor control. Each section presents a statement of the problem, a review of general solutions, and specific recommendations. The report is concluded with a brief consideration of how selection, training, and other procedures can also help Space Station occupants achieve satisfactory levels of seclusion.

  12. Design and development of electric vehicle charging station equipped with RFID

    NASA Astrophysics Data System (ADS)

    Panatarani, C.; Murtaddo, D.; Maulana, D. W.; Irawan, S.; Joni, I. M.

    2016-02-01

    This paper reports the development of electric charging station from distributed renewable for electric vehicle (EV). This designed refer to the input voltage standard of IEC 61851, plugs features of IEC 62196 and standard communication of ISO 15118. The developed electric charging station used microcontroller ATMEGA8535 and RFID as controller and identifier of the EV users, respectively. The charging station successfully developed as desired features for electric vehicle from renewable energy resources grid with solar panel, wind power and batteries storage.

  13. International interface design for Space Station Freedom - Challenges and solutions

    NASA Technical Reports Server (NTRS)

    Mayo, Richard E.; Bolton, Gordon R.; Laurini, Daniele

    1988-01-01

    The definition of interfaces for the International Space Station is discussed, with a focus on negotiations between NASA and ESA. The program organization and division of responsibilities for the Space Station are outlined; the basic features of physical and functional interfaces are described; and particular attention is given to the interface management and documentation procedures, architectural control elements, interface implementation and verification, and examples of Columbus interface solutions (including mechanical, ECLSS, thermal-control, electrical, data-management, standardized user, and software interfaces). Diagrams, drawings, graphs, and tables listing interface types are provided.

  14. Electrical power system design for the US space station

    NASA Technical Reports Server (NTRS)

    Nored, Donald L.; Bernatowicz, Daniel T.

    1986-01-01

    The multipurpose, manned, permanent space station will be our next step toward utilization of space. A multikilowatt electrical power system will be critical to its success. The power systems for the space station manned core and platforms that have been selected in definition studies are described. The system selected for the platforms uses silicon arrays and Ni-H2 batteries. The power system for the manned core is a hybrid employing arrays and batteries identical to those on the platform along with solar dynamic modules using either Brayton or organic Rankine engines. The power system requirements, candidate technologies, and configurations that were considered, and the basis for selection, are discussed.

  15. Design and optimization of LCL-VSC grid-tied converter having short circuit fault current limiting ability

    NASA Astrophysics Data System (ADS)

    Liu, Mengqi; Liu, Haijun; Wang, Zhikai

    2017-01-01

    Traditional LCL grid-tied converters haven't the ability to limit the short-circuit fault current and only remove grid-connected converter using the breaker. However, the VSC converters become uncontrollable after the short circuit fault cutting off and the power switches may be damaged if the circuit breaker removes slowly. Compared to the filter function of the LCL passive components in traditional VSC converters, the novel LCL-VSC converter has the ability of limiting the short circuit fault current using the reasonable designed LCL parameters. In this paper the mathematical model of the LCL converter is established and the characteristics of the short circuit fault current generated by the ac side and dc side are analyzed. Thus one design and optimization scheme of the reasonable LCL passive parameter is proposed for the LCL-VSC converter having short circuit fault current limiting ability. In addition to ensuring the LCL passive components filtering the high-frequency harmonic, this scheme also considers the impedance characteristics to limit the fault current of AC and DC short circuit fault respectively flowing through the power switch no more than the maximum allowable operating current, in order to make the LCL converter working continuously. Finally, the 200kW simulation system is set up to prove the validity and feasibility of the theoretical analysis using the proposed design and optimization scheme.

  16. Design of photon converter and photoneutron target for High power electron accelerator based BNCT.

    PubMed

    Rahmani, Faezeh; Seifi, Samaneh; Anbaran, Hossein Tavakoli; Ghasemi, Farshad

    2015-12-01

    An electron accelerator, ILU-14, with current of 10 mA and 100 kW in power has been considered as one of the options for neutron source in Boron Neutron Capture Therapy (BNCT). The final design of neutron target has been obtained using MCNPX to optimize the neutron production. Tungsten in strip shape and D2O in cylindrical form have been proposed as the photon converter and the photoneutron target, respectively. In addition calculation of heat deposition in the photon target design has been considered to ensure mechanical stability of target. The results show that about 8.37×10(12) photoneutron/s with average energy of 615 keV can be produced by this neutron source design. In addition, using an appropriate beam shaping assembly an epithermal neutron flux of the order of 1.24×10(8) cm(-2) s(-1) can be obtained for BNCT applications.

  17. Converter-Modulator Design and Operations for the ILC L-band Test Stand

    SciTech Connect

    Reass, William A.; Burkhart, C.; Adolphsen, Chris E.; Beukers, T.; Cassel, R.; de Lira, A.; Papas, C.; Nguyen, M.; Went, R.; Anderson, David E.; /Oak Rdige

    2007-09-10

    To facilitate a rapid response to the International Linear Collider (ILC) L-band development program at SLAC, a spare converter-modulator was shipped from LANL. This modulator was to be a spare for the spallation neutron source (SNS) accelerator at ORNL. The ILC application requires a 33% higher peak output power (15 MW) and output current (120 Amp). This presents significant design challenges to modify the existing hardware and yet maintain switching parameters and thermal cycling within the semiconductor component ratings. To minimize IGBT commutation and free-wheeling diode currents, a different set of optimizations, as compared to the SNS design, were used to tune the resonant switching networks. Additional complexities arose as nanocrystalline cores with different performance characteristics (as compared to SNS), were used to fabricate the resonant 'boost' transformers. This paper will describe the electrical design, modeling efforts, and resulting electrical performance as implemented for the ILC L-band test stand.

  18. The Space Station program definition and preliminary systems design - Recent developments

    NASA Technical Reports Server (NTRS)

    Freitag, R. F.

    1985-01-01

    It is pointed out that space stations represent a major vehicle for accomplishing many things mankind envisions for space activities. Thus, space stations have become necessary stepping-off points for deep-space expeditions, and it is expected that they will lead eventually to the permanent occupancy of another planet. The present paper provides a report regarding planning activities in the U.S. and in other countries which have made significant progress in making a permanent Space Station a reality. The Space Station will consist of a manned base and associated platforms, as well as collateral support equipment. The purpose of the program definition and preliminary design activities (Phase B) is to arrive at the baseline configuration before initiating actual hardware development. Details of the program plan are discussed along with user considerations in design, the commercialization of space, design issues, operations, and Space Station evolution.

  19. AC/DC converter

    NASA Astrophysics Data System (ADS)

    Jain, Praveen K.

    1992-08-01

    In a system such as a 20 kHz space station primary electrical power distribution system, power conversion from AC to DC is required. Some of the basic requirements for this conversion are high efficiency, light weight and small volume, regulated output voltage, close to unity input power factor, distortionless input current, soft-starting, low electromagnetic interference, and high reliability. An AC-to-DC converter is disclosed which satisfies the main design objectives of such converters for use in space. The converter of the invention comprises an input transformer, a resonant network, a current controller, a diode rectifier, and an output filter. The input transformer is for connection to a single phase, high frequency, sinusoidal waveform AC voltage source and provides a matching voltage isolating from the AC source. The resonant network converts this voltage to a sinusoidal, high frequency bidirectional current output, which is received by the current controller to provide the desired output current. The diode rectifier is connected in parallel with the current controller to convert the bidirectional current into a unidirectional current output. The output filter is connected to the rectifier to provide an essentially ripple-free, substantially constant voltage DC output.

  20. The design and development of a mobile transporter system for the Space Station Remote Manipulator System

    NASA Technical Reports Server (NTRS)

    Carroll, Thomas W.

    1987-01-01

    The analyses, selection process, and conceptual design of potential candidate Mobile Transporter (MT) systems to move the Space Station Remote Manipulator System (SSRMS) about the exposed faces of the Space Station truss structure are described. The actual requirements for a manipulator system on the space station are discussed, including potential tasks to be performed. The SSRMS operating environment and control methods are analyzed with potential design solutions highlighted. Three general categories of transporter systems are identified and analyzed. Several design solution have emerged that will satisfy these requirements. Their relative merits are discussed, and unique variations in each system are rated for functionality.

  1. A home away from home. [life support system design for Space Station

    NASA Technical Reports Server (NTRS)

    Powell, L. E.; Hager, R. W.; Mccown, J. W.

    1985-01-01

    The role of the NASA-Marshall center in the development of the Space Station is discussed. The tasks of the center include the development of the life-support system; the design of the common module, which will form the basis for all pressurized Space Station modules; the design and outfit of a common module for the Material and Technology Laboratory (MTL) and logistics use; accommodations for operations of the Orbit Maneuvering Vehicle (OMV) and the Orbit Transfer Vehicle (OTV); and the Space Station propulsion system. A description of functions and design is given for each system, with particular emphasis on the goals of safety, efficiency, automation, and cost effectiveness.

  2. Space Station automated systems testing/verification and the Galileo Orbiter fault protection design/verification

    NASA Technical Reports Server (NTRS)

    Landano, M. R.; Easter, R. W.

    1984-01-01

    Aspects of Space Station automated systems testing and verification are discussed, taking into account several program requirements. It is found that these requirements lead to a number of issues of uncertainties which require study and resolution during the Space Station definition phase. Most, if not all, of the considered uncertainties have implications for the overall testing and verification strategy adopted by the Space Station Program. A description is given of the Galileo Orbiter fault protection design/verification approach. Attention is given to a mission description, an Orbiter description, the design approach and process, the fault protection design verification approach/process, and problems of 'stress' testing.

  3. Conceptual design and evaluation of selected Space Station concepts: Executive summary

    NASA Technical Reports Server (NTRS)

    1983-01-01

    The results of a space station conceptual design and evaluation study are summarized. The study represented a temporary focusing. Three space station configurations are characterized for user and crew requirements, operation and safety accommodations, engineering considerations including assembly and growth, structural dynamics, communications, thermal control and power systems, as well as system cost.

  4. Design of a mechanism for converting the energy of knee motions by using electroactive polymers.

    PubMed

    Armbruster, Pascal; Oster, Yannick; Vogt, Marcel; Pylatiuk, Christian

    2017-03-04

    Harvesting energy from human body motions has become a promising option to prolong battery life for powering medical devices for autonomy. Up to now, different generating principles including dielectric electroactive polymers (DEAPs) have been suggested for energy conversion. However, there is a lack of mechanisms that are specifically designed to convert energy with DEAPs. In a proof of concept study, a mechanical system was designed for stretching DEAPs in those phases of the gait cycle, in which the muscles mainly perform negative work. Rotational movements of the knee joint are transformed into linear movements by using a cable pull. The DEAP can be charged during the stretching phase and discharged during releasing and allows for the conversion of kinetic energy into electric energy. To evaluate the concept, tests were conducted. It was found that the developed body energy harvesting (BEH) system has a performance in the range of 24-40 μW at normal walking speed. The converted energy is sufficient for powering sensors in medical devices such as active orthoses or prostheses.

  5. Designing perfect linear polarization converters using perfect electric and magnetic conducting surfaces

    PubMed Central

    Zhou, Gaochao; Tao, Xudong; Shen, Ze; Zhu, Guanghao; Jin, Biaobing; Kang, Lin; Xu, Weiwei; Chen, Jian; Wu, Peiheng

    2016-01-01

    We propose a kind of general framework for the design of a perfect linear polarization converter that works in the transmission mode. Using an intuitive picture that is based on the method of bi-directional polarization mode decomposition, it is shown that when the device under consideration simultaneously possesses two complementary symmetry planes, with one being equivalent to a perfect electric conducting surface and the other being equivalent to a perfect magnetic conducting surface, linear polarization conversion can occur with an efficiency of 100% in the absence of absorptive losses. The proposed framework is validated by two design examples that operate near 10 GHz, where the numerical, experimental and analytic results are in good agreements. PMID:27958313

  6. User's manual: Computer-aided design programs for inductor-energy-storage dc-to-dc electronic power converters

    NASA Technical Reports Server (NTRS)

    Huffman, S.

    1977-01-01

    Detailed instructions on the use of two computer-aided-design programs for designing the energy storage inductor for single winding and two winding dc to dc converters are provided. Step by step procedures are given to illustrate the formatting of user input data. The procedures are illustrated by eight sample design problems which include the user input and the computer program output.

  7. Designing a new post-hole seismological station on Antarctica inlandsis (Concordia station)

    NASA Astrophysics Data System (ADS)

    Bès de Berc, M.; Maggi, A.; Leveque, J. J.; Thore, J. Y.

    2015-12-01

    Concordia (75°S 123°E) is a scientific base operated by French and Italian polar institutes IPEV (Institut Paul-Emile Victor) and PNRA (Programma Nazionale di Ricerche in Antartide, and is located on the inlandsis of the East Antarctica plateau. It hosts a seismological station CCD which has provided observatory quality data since the year 2000, has been integrated into the Geoscope network since 2008 and whose data are now available in real-time from IRIS. The current seismic vault is located 800m from Concordia base, as far away as is deemed logistically possible by IPEV, at a depth of 12m. The vault is thermally very stable, but given the close distance to the base, suffers from increased diurnal noise (up to 40 dB) at frequencies above 1Hz, especially in the summer season. Anthropic noise is trapped in the firn (snow) layer, which forms an 100-110m thick waveguide, and is picked up very easily in the seismic vault. The vault is made from steel containers buried vertically in the snow. The hydrostatic pressure of the snow is deforming them: we see container cracking events on the seismograms, and also visual evidence of container deformation inside the vault. In the near future, this deformation will create a security problem.We have decided to progressively abandon our current vault, and construct a new post-hole seismological installation nearby. We plan to drill to 130m depth, which would place us below the firn layer waveguide and also below the ice pinch-out depth. To be able to run the station for several years and change or service the instrumentation if required, we need to keep the hole open, to avoid any hydrostatic movement, and to maintain good coupling between the sensor and the surrounding hard ice. To achieve these goals, we shall install a casing in the fin layer and then drill a few meters more without casing in hard ice. After installing the instrument, we shall then fill the whole hole with a drilling fluid whose density is similar to that

  8. Applying real-time operations to integrate and evaluate Space Station Freedom design

    NASA Technical Reports Server (NTRS)

    Schmidt, George; Winkler, David

    1990-01-01

    During its 30 year lifetime, Space Station Freedom will provide unique opportunities for a variety of research, commercial and space exploration activities. The diversity of Freedom's on-orbit operations and the partitioning of the spacecraft's flight elements and systems requires consideration of operations early in the design development. This paper presents a method for defining a structured relationship between Space Station Freedom real-time operations and system functionality, and discusses how this relationship can be used when evaluating the spacecraft design.

  9. Considerations in the design of life sciences research facilities for the Space Station

    NASA Technical Reports Server (NTRS)

    Heinrich, M.; Rudiger, C. E.

    1985-01-01

    The facilities required for life science research on a permanent Space Station are examined. Specifications important to the designing of facilities and planning of activities on the Space Shuttle are: (1) the species to be tested, (2) the number and procedure for testing, (3) the number of specimens at each sampling time, (4) the analyses required, (5) the methods of preserving samples, instruments, and supplies, and (6) the amount of crew time required. Experiments which are relevant to understanding the effects of microgravity on living systems are to be performed on the Space Station. The design and instruments of a Space Station laboratory and specimen centrifuge are described.

  10. Designed cell consortia as fragrance-programmable analog-to-digital converters.

    PubMed

    Müller, Marius; Ausländer, Simon; Spinnler, Andrea; Ausländer, David; Sikorski, Julian; Folcher, Marc; Fussenegger, Martin

    2017-03-01

    Synthetic biology advances the rational engineering of mammalian cells to achieve cell-based therapy goals. Synthetic gene networks have nearly reached the complexity of digital electronic circuits and enable single cells to perform programmable arithmetic calculations or to provide dynamic remote control of transgenes through electromagnetic waves. We designed a synthetic multilayered gaseous-fragrance-programmable analog-to-digital converter (ADC) allowing for remote control of digital gene expression with 2-bit AND-, OR- and NOR-gate logic in synchronized cell consortia. The ADC consists of multiple sampling-and-quantization modules sensing analog gaseous fragrance inputs; a gas-to-liquid transducer converting fragrance intensity into diffusible cell-to-cell signaling compounds; a digitization unit with a genetic amplifier circuit to improve the signal-to-noise ratio; and recombinase-based digital expression switches enabling 2-bit processing of logic gates. Synthetic ADCs that can remotely control cellular activities with digital precision may enable the development of novel biosensors and may provide bioelectronic interfaces synchronizing analog metabolic pathways with digital electronics.

  11. Design of piezoelectric transformer for DC/DC converter with stochastic optimization method

    NASA Astrophysics Data System (ADS)

    Vasic, Dejan; Vido, Lionel

    2016-04-01

    Piezoelectric transformers were adopted in recent year due to their many inherent advantages such as safety, no EMI problem, low housing profile, and high power density, etc. The characteristics of the piezoelectric transformers are well known when the load impedance is a pure resistor. However, when piezoelectric transformers are used in AC/DC or DC/DC converters, there are non-linear electronic circuits connected before and after the transformer. Consequently, the output load is variable and due to the output capacitance of the transformer the optimal working point change. This paper starts from modeling a piezoelectric transformer connected to a full wave rectifier in order to discuss the design constraints and configuration of the transformer. The optimization method adopted here use the MOPSO algorithm (Multiple Objective Particle Swarm Optimization). We start with the formulation of the objective function and constraints; then the results give different sizes of the transformer and the characteristics. In other word, this method is looking for a best size of the transformer for optimal efficiency condition that is suitable for variable load. Furthermore, the size and the efficiency are found to be a trade-off. This paper proposes the completed design procedure to find the minimum size of PT in need. The completed design procedure is discussed by a given specification. The PT derived from the proposed design procedure can guarantee both good efficiency and enough range for load variation.

  12. Steady-state analysis and design of the parallel resonant converter

    NASA Astrophysics Data System (ADS)

    Johnson, Steven D.; Erickson, Robert W.

    1988-01-01

    Five basic operating modes of the parallel resonant converter are analyzed. Three of the modes occur when the output filter inductor is removed and the remaining two occur wehn the filter inductor is large. Closed-form solutions are found for the two most important modes. Switching frequency, peak tank capacitor voltage, and peak tank inductor current are plotted in the output plane. These plots, with a load line superimposed, show how operating point, frequency, and peak stresses vary as load conditions change. Use of the output plane plots to minimize component costs is explained. Comparison of the best designs found for the large and zero filter inductance cases shows that removing the filter inductor can reduce both parts count and tank circuit size while peak transistor current remains unchanged.

  13. Manipulator arm design for the Extravehicular Teleoperator Assist Robot (ETAR): Applications on the space station

    NASA Technical Reports Server (NTRS)

    Clarke, Margaret M.; Divona, Charles J.; Thompson, William M.

    1987-01-01

    The preliminary conceptual design of a new teleoperator robot manipulator system for space station maintenance missions has been completed. The system consists of a unique pair of arms that is part of a master-slave, force-reflecting servomanipulator. This design allows greater dexterity and greater volume coverage than that available in current designs and concepts. The teleoperator manipulator is specifically designed for space applications and is a valuable extension of the current state-of-the-art earthbound manipulators marketed today. The manipulator and its potential application on the space station are described.

  14. A lithium-cooled reactor - Brayton turboelectric power converter design for 100-kWe class space reactor electric systems

    SciTech Connect

    Anderson, R.V.

    1984-08-01

    The conceptual design of a 100-kWe space reactor electric system to satisfy the design goals of the Tri-Agency SP-100 Program has been completed. The system was selected from an initial field of over 500 potential choices covering a wide range of reactor, power converter, shield, heat transport, and radiator subsystems. The selected system -- a lithium-cooled, UN-fueled, refractory-clad reactor coupled to a redundant pair of 110-kWe (gross) Brayton turboelectric power converters -shows strong promise of not only meeting the SP-100 Program design goals but also of providing for substantial growth in power levels for potential future needs.

  15. SDTM - SYSTEM DESIGN TRADEOFF MODEL FOR SPACE STATION FREEDOM RELEASE 1.1

    NASA Technical Reports Server (NTRS)

    Chamberlin, R. G.

    1994-01-01

    Although extensive knowledge of space station design exists, the information is widely dispersed. The Space Station Freedom Program (SSFP) needs policies and procedures that ensure the use of consistent design objectives throughout its organizational hierarchy. The System Design Tradeoff Model (SDTM) produces information that can be used for this purpose. SDTM is a mathematical model of a set of possible designs for Space Station Freedom. Using the SDTM program, one can find the particular design which provides specified amounts of resources to Freedom's users at the lowest total (or life cycle) cost. One can also compare alternative design concepts by changing the set of possible designs, while holding the specified user services constant, and then comparing costs. Finally, both costs and user services can be varied simultaneously when comparing different designs. SDTM selects its solution from a set of feasible designs. Feasibility constraints include safety considerations, minimum levels of resources required for station users, budget allocation requirements, time limitations, and Congressional mandates. The total, or life cycle, cost includes all of the U.S. costs of the station: design and development, purchase of hardware and software, assembly, and operations throughout its lifetime. The SDTM development team has identified, for a variety of possible space station designs, the subsystems that produce the resources to be modeled. The team has also developed formulas for the cross consumption of resources by other resources, as functions of the amounts of resources produced. SDTM can find the values of station resources, so that subsystem designers can choose new design concepts that further reduce the station's life cycle cost. The fundamental input to SDTM is a set of formulas that describe the subsystems which make up a reference design. Most of the formulas identify how the resources required by each subsystem depend upon the size of the subsystem. Some of

  16. Instructor/Operator Station Design Handbook for Aircrew Training Devices.

    DTIC Science & Technology

    1987-10-01

    concept which emerged is presented from the viewpoints of instructional design, operational instruction, and performance measurement design. Polzella , D.J...capabilities of future ATDs and the need for empirical research aimed at determining the principles of effective AIF use. Polzella , D.J., & Hubbard...and design deficiencies. The perceived training value of a feature was the most important determiner of its use. Polzella , D.J. (1985). Aircrew training

  17. Report on the findings of the Japanese Investigative Team on US Space Station Design (Keidanren)

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The objectives, itinerary and results of the Japanese Investigative Team on U.S. Space Station Design (Keidanren), consisting of members of the Space Development Promotion Council and representatives of Japanese industries involved in Japan's space station development effort are presented. This team visited NASA facilities in February, 1985. The objectives of the study team are to gather information on preliminary design efforts toward space station planning in Japan and the promotion of Japanese space related industries, as well as the evaluation of the present status of space environment exploitation in the U.S. This report is intended to be a basic reference for government agencies and industry in addressing the course of action to be taken in the future development of Japan's space station participation.

  18. 9 CFR 72.16 - Designated dipping stations to be approved by the Administrator, APHIS on recommendations of...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... CATTLE § 72.16 Designated dipping stations to be approved by the Administrator, APHIS on recommendations... points at which cattle of the quarantined area of the State in which said station is located may...

  19. 9 CFR 72.16 - Designated dipping stations to be approved by the Administrator, APHIS on recommendations of...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... CATTLE § 72.16 Designated dipping stations to be approved by the Administrator, APHIS on recommendations... points at which cattle of the quarantined area of the State in which said station is located may...

  20. The Space Station Freedom Flight Telerobotic Servicer - The design and evolution of a dexterous space robot

    NASA Technical Reports Server (NTRS)

    Mccain, Harry G.; Andary, James F.; Hewitt, Dennis R.; Haley, Dennis C.

    1990-01-01

    The Flight Telerobotic Servicer (FTS) will provide a telerobotic capability to the Space Station in the early assembly phases of the program and will be used for assembly, maintenance, and inspection throughout the lifetime of the Station. Here, the FTS design approach to the development of autonomous capabilities is discussed. The FTS telerobotic workstations for the Shuttle and Space Station, and facility for on-orbit storage are examined. The rationale of the FTS with regard to ease of operation, operational versatility, maintainability, safety, and control is discussed.

  1. Life support and internal thermal control system design for the Space Station Freedom

    NASA Technical Reports Server (NTRS)

    Humphries, R.; Mitchell, K.; Reuter, J.; Carrasquillo, R.; Beverly, B.

    1991-01-01

    A Review of the Space Station Freedom Environmental Control and Life Support System (ECLSS) as well as the Internal Thermal Control System (ITCS) design, including recent changes resulting from an activity to restructure the program, is provided. The development state of the original Space Station Freedom ECLSS through the restructured configuration is considered and the selection of regenerative subsystems for oxygen and water reclamation is addressed. A survey of the present ground development and verification program is given.

  2. Life support and internal thermal control system design for the Space Station Freedom

    NASA Astrophysics Data System (ADS)

    Humphries, R.; Mitchell, K.; Reuter, J.; Carrasquillo, R.; Beverly, B.

    1991-12-01

    A Review of the Space Station Freedom Environmental Control and Life Support System (ECLSS) as well as the Internal Thermal Control System (ITCS) design, including recent changes resulting from an activity to restructure the program, is provided. The development state of the original Space Station Freedom ECLSS through the restructured configuration is considered and the selection of regenerative subsystems for oxygen and water reclamation is addressed. A survey of the present ground development and verification program is given.

  3. Structure based drug design of angiotensin-I converting enzyme inhibitors.

    PubMed

    Anthony, C S; Masuyer, G; Sturrock, E D; Acharya, K R

    2012-01-01

    Cardiovascular disease (CVD) is responsible for ∼27% of deaths worldwide, with 80% of these occuring in developing countries. Hypertension is one of the most important treatable factors in the prevention of CVD. Angiotensin-I converting enzyme (ACE) is a two-domain dipeptidylcarboxypeptidase that is a key regulator of blood pressure as a result of its critical role in the reninangiotensin- aldosterone and kallikrien-kinin systems. Consequently, ACE is an important drug target in the treatment of CVD. ACE is primarily known for its ability to cleave angiotensin-I to the vasoactive octapeptide angiotensin-II, but is also able to cleave a number of other substrates including the vasodilator bradykinin and N-acetyl-seryl-aspartyl-lysyl-proline (acetyl-SDKP), a physiological modulator of hematopoiesis. Numerous ACE inhibiors are available clinically, and these are generally effective in treating hypertension. However some adverse effects are associated with ACE inhibition, such as the persistent dry cough and the potentially fatal angioedema. The solution of ACE crystal structures over the last decade has facilitated rational drug design which has contributed to the development of domain-selective ACE inhibitors, the most notable of which include RXP407 (N-domain) and RXPA380 (C-domain), which in principle may herald new therapeutic approaches for ACE inhibition. Additionally, dual inhibitors to ACE and other targets such as neprilysin, endothelin converting enzyme and chymase have been developed. The success of ACE inhibitors has also led to the search for novel inhibitors in food and natural products and the structure guided screening of such libraries may well reveal a number of new ACE inhibitors.

  4. DESIGNING AN OPPORTUNITY FUEL WITH BIOMASS AND TIRE-DERIVED FUEL FOR COFIRING AT WILLOW ISLAND GENERATING STATION AND COFIRING SAWDUST WITH COAL AT ALBRIGHT GENERATING STATION

    SciTech Connect

    K. Payette; D. Tillman

    2004-01-01

    During the period October 1, 2003-December 31, 2003, Allegheny Energy Supply Co., LLC (Allegheny) continued with demonstration operations at the Willow Island Generating Station and improvements to the Albright Generating Station cofiring systems. The demonstration operations at Willow Island were designed to document integration of biomass cofiring into commercial operations, including evaluating new sources of biomass supply. The Albright improvements were designed to increase the resource base for the projects, and to address issues that came up during the first year of operations. This report summarizes the activities associated with the Designer Opportunity Fuel program, and demonstrations at Willow Island and Albright Generating Stations.

  5. DESIGNING AN OPPORTUNITY FUEL WITH BIOMASS AND TIRE-DERIVED FUEL FOR COFIRING AT WILLOW ISLAND GENERATING STATION AND COFIRING SAWDUST WITH COAL AT ALBRIGHT GENERATING STATION

    SciTech Connect

    K. Payette; D. Tillman

    2003-07-01

    During the period April 1, 2003--June 30, 2003, Allegheny Energy Supply Co., LLC (Allegheny) proceeded with demonstration operations at the Willow Island Generating Station and improvements to the Albright Generating Station cofiring systems. The demonstration operations at Willow Island were designed to document integration of biomass cofiring into commercial operations. The Albright improvements were designed to increase the resource base for the projects, and to address issues that came up during the first year of operations. This report summarizes the activities associated with the Designer Opportunity Fuel program, and demonstrations at Willow Island and Albright Generating Stations.

  6. Space station Simulation Computer System (SCS) study for NASA/MSFC. Volume 4: Conceptual design report

    NASA Technical Reports Server (NTRS)

    1989-01-01

    The Simulation Computer System (SCS) is the computer hardware, software, and workstations that will support the Payload Training Complex (PTC) at Marshall Space Flight Center (MSFC). The PTC will train the space station payload scientists, station scientists, and ground controllers to operate the wide variety of experiments that will be onboard the Space Station Freedom. In the first step of this task, a methodology was developed to ensure that all relevant design dimensions were addressed, and that all feasible designs could be considered. The development effort yielded the following method for generating and comparing designs in task 4: (1) Extract SCS system requirements (functions) from the system specification; (2) Develop design evaluation criteria; (3) Identify system architectural dimensions relevant to SCS system designs; (4) Develop conceptual designs based on the system requirements and architectural dimensions identified in step 1 and step 3 above; (5) Evaluate the designs with respect to the design evaluation criteria developed in step 2 above. The results of the method detailed in the above 5 steps are discussed. The results of the task 4 work provide the set of designs which two or three candidate designs are to be selected by MSFC as input to task 5-refine SCS conceptual designs. The designs selected for refinement will be developed to a lower level of detail, and further analyses will be done to begin to determine the size and speed of the components required to implement these designs.

  7. Design of a photovoltaic central power station: flat-plate array

    SciTech Connect

    Not Available

    1984-02-01

    A design for a photovoltaic central power station using fixed flat-panel arrays has been developed. The 100 MW plant is assumed to be located adjacent to the Saguaro Power Station of Arizona Public Service. The design assumes high-efficiency photovoltaic modules using dendritic web cells. The modules are arranged in 5 MW subfields, each with its own power conditioning unit. The photovoltaic output is connected to the existing 115 kV utility switchyard. The site specific design allows detailed cost estimates for engineering, site preparation, and installation. Collector and power conditioning costs have been treated parametrically.

  8. Design and analysis of an SOI MEMS voltage step-up converter

    NASA Astrophysics Data System (ADS)

    Gleeson, R.; Kraft, M.; White, N. M.

    2013-11-01

    This paper presents a comprehensive analysis of a MEMS voltage step-up converter for energy harvesting and other low-power applications. The step-up operation is based on isolating the charge of a mechanically variable capacitor and varying the gap between the electrodes by an appropriate method of providing an actuation force. A bi-stable device is discussed and was specifically designed for static energy harvesting. This device features a separate electrostatic actuator element to manipulate the variable capacitor electrodes. Prototypes were then fabricated using a dicing-free silicon-on-insulator process. The devices have been arbitrarily designed to produce an output voltage which is five times the magnitude of the input (M = 5). Due to leakage currents, it was necessary to cascade the MEMS capacitors in parallel to obtain a higher capacitance level. Parasitic fringing capacitances have a substantial impact on the overall capacitance value of the MEMS device and so the measured multiplication level of the devices is limited to M = 2.125. With four devices in parallel, a maximum output voltage of 35.4 V was obtained for a 24 V input was measured. However, a maximum output voltage of ≈60 V is achievable if the capacitance value was further increased by connecting more devices in parallel or if or the load resistance was increased beyond 1 GΩ.

  9. The Electromagnetic Compatibility (EMC) Design Challenge for Scientific Spacecraft Powered by a Stirling Power Converter

    NASA Technical Reports Server (NTRS)

    Sargent, Noel B.

    2001-01-01

    A 55 We free-piston Stirling Technology Demonstration Convertor (TDC) has been tested as part of an evaluation to determine its feasibility as a means for significantly reducing the amount of radioactive material required compared to Radioisotope Thermoelectric Generators (RTGs) to support long-term space science missions. Measurements were made to quantify the low frequency magnetic and electric fields radiated from the Stirling's 80 Hertz (Hz) linear alternator and control electronics in order to determine the magnitude of reduction that will be required to protect sensitive field sensors aboard some science missions. One identified "Solar Probe" mission requires a 100 dB reduction in the low frequency magnetic field over typical military standard design limits, to protect its plasma wave sensor. This paper discusses the electromagnetic interference (EMI) control options relative to the physical design impacts for this power system, composed of 3 basic electrical elements. They are (1) the Stirling Power Convertor with its linear alternator, (2) the power switching and control electronics to convert the 90 V, 80 Hz alternator output to DC for the use of the spacecraft, and (3) the interconnecting wiring including any instrumentation to monitor and control items 1 and 2.

  10. Design of a 12-megapixel imager with a nanowatt A/D converter at each pixel

    NASA Astrophysics Data System (ADS)

    Mandl, William J.

    2003-09-01

    The design for a large format digital visible light area array was developed based on A/D conversion at each pixel. Production CMOS technology was used in the development of a monolithic front side illuminated photo diode pixel. Each pixel includes a one loop MOSAD, multiplexed oversample A/D, converter, the photo diode and a buffered output to support a very large array format operating at a high frame rate. MOSAD is a modification of the delta sigma approach to A/D conversion. The requirements are to develop a 4,000 x 3,000 pixel array capable of up to 1,000 frames per second sample rate. A design was developed using the AMIS 0.35 μm CMOS process with a single poly and three metal layers. To approximately fit a 35 millimeter optics format, a pixel size of 8.5 μm was selected. There are no operational amplifiers required at the pixel to perform the A/D function, thus allowing a high fill factor. With this pixel size, a 48% fill factor and 38% photo diode area was achieved. The design can produce a pixel size of 4.3 μm square with the use of 0.18 μm CMOS without sacrificing fill factor. Alternate approaches to satisfy the 1 kiloframe sample rate with up to 10 bits dynamic range were analyzed. The design is still in progress with layout and simulation of the critical elements complete. This development program is sponsored by the Army White Sands Missile Range.

  11. Crew factors in the design of the Space Station

    NASA Technical Reports Server (NTRS)

    Robinson, Judith L.

    1987-01-01

    The designing of Space Shuttle modules and equipment in order to provide a stimulating and efficient work atmosphere and a pleasant living environment is examined. The habitation module for the eight crew members is divided into four areas: ceiling, floor, port, and starboard. The module is to consist of crew quarters, a wardroom, a galley, a personal hygiene facility, a health maintenance facility, and stowage areas. There is a correlation between the function of the module and its location; for example the galley will be near the wardroom and the personal hygiene facility near the crew quarters. The designs of the equipment for crew accommodation and of the equipment to be maintained and repaired by the crew will be standarized. The design and functions of the crew and equipment restraints, crew mobility aids, racks to contain equipment, and functional units are described.

  12. Design, processing, and testing of LSI arrays for space station

    NASA Technical Reports Server (NTRS)

    Ipri, A. C.

    1976-01-01

    The applicability of a particular process for the fabrication of large scale integrated circuits is described. Test arrays were designed, built, and tested, and then utilized. A set of optimum dimensions for LSI arrays was generated. The arrays were applied to yield improvement through process innovation, and additional applications were suggested in the areas of yield prediction, yield modeling, and process reliability.

  13. Design and Performance of the Acts Gigabit Satellite Network High Data-Rate Ground Station

    NASA Technical Reports Server (NTRS)

    Hoder, Doug; Kearney, Brian

    1995-01-01

    The ACTS High Data-Rate Ground stations were built to support the ACTS Gigabit Satellite Network (GSN). The ACTS GSN was designed to provide fiber-compatible SONET service to remote nodes and networks through a wideband satellite system. The ACTS satellite is unique in its extremely wide bandwidth, and electronically controlled spot beam antennas. This paper discusses the requirements, design and performance of the RF section of the ACTS High Data-Rate Ground Stations and constituent hardware. The ACTS transponder systems incorporate highly nonlinear hard limiting. This introduced a major complexity in to the design and subsequent modification of the ground stations. A discussion of the peculiarities of the A CTS spacecraft transponder system and their impact is included.

  14. Conceptual design and integration of a space station resistojet propulsion assembly

    NASA Technical Reports Server (NTRS)

    Tacina, Robert R.

    1987-01-01

    The resistojet propulsion module is designed as a simple, long life, low risk system offering operational flexibility to the space station program. It can dispose of a wide variety of typical space station waste fluids by using them as propellants for orbital maintenance. A high temperature mode offers relatively high specific impulse with long life while a low temperature mode can propulsively dispose of mixtures that contain oxygen or hydrocarbons without reducing thruster life or generating particulates in the plume. A low duty cycle and a plume that is confined to a small aft region minimizes the impacts on the users. Simple interfaces with other space station systems facilitate integration. It is concluded that there are no major obstacles and many advantages to developing, installing, and operating a resistojet propulsion module aboard the Initial Operational Capability (IOC) space station.

  15. DESIGNING AN OPPORTUNITY FUEL WITH BIOMASS AND TIRE-DERIVED FUEL FOR COFIRING AT WILLOW ISLAND GENERATING STATION AND COFIRING SAWDUST WITH COAL AT ALBRIGHT GENERATING STATION

    SciTech Connect

    K. Payette; D. Tillman

    2003-04-30

    During the period January 1, 2003--March 31, 2003, Allegheny Energy Supply Co., LLC (Allegheny) proceeded with improvements to both the Willow Island and Albright Generating Station cofiring systems. These improvements were designed to increase the resource base for the projects, and to address issues that came up during the first year of operations. This report summarizes the activities associated with the Designer Opportunity Fuel program, and demonstrations at Willow Island and Albright Generating Stations.

  16. Coupled Mooring Analyses for the WEC-Sim Wave Energy Converter Design Tool: Preprint

    SciTech Connect

    Sirnivas, Senu; Yu, Yi-Hsiang; Hall, Matthew; Bosma, Bret

    2016-07-01

    A wave-energy-converter-specific time-domain modeling method (WEC-Sim) was coupled with a lumped-mass-based mooring model (MoorDyn) to improve its mooring dynamics modeling capability. This paper presents a verification and validation study on the coupled numerical method. First, a coupled model was built to simulate a 1/25 model scale floating power system connected to a traditional three-point catenary mooring with an angle of 120 between the lines. The body response and the tension force on the mooring lines at the fairlead in decay tests and under regular and irregular waves were examined. To validate and verify the coupled numerical method, the simulation results were compared to the measurements from a wave tank test and a commercial code (OrcaFlex). Second, a coupled model was built to simulate a two-body point absorber system with a chain-connected catenary system. The influence of the mooring connection on the point absorber was investigated. Overall, the study showed that the coupling of WEC-Sim and the MoorDyn model works reasonably well for simulating a floating system with practical mooring designs and predicting the corresponding dynamic loads on the mooring lines. Further analyses on improving coupling efficiency and the feasibility of applying the numerical method to simulate WEC systems with more complex mooring configuration are still needed.

  17. Coupled Mooring Analyses for the WEC-Sim Wave Energy Converter Design Tool

    SciTech Connect

    Sirnivas, Senu; Yu, Yi-Hsiang; Hall, Matthew; Bosma, Bret

    2016-06-24

    A wave-energy-converter-specific time-domain modeling method (WEC-Sim) was coupled with a lumped-mass-based mooring model (MoorDyn) to improve its mooring dynamics modeling capability. This paper presents a verification and validation study on the coupled numerical method. First, a coupled model was built to simulate a 1/25 model scale floating power system connected to a traditional three-point catenary mooring with an angle of 120 between the lines. The body response and the tension force on the mooring lines at the fairlead in decay tests and under regular and irregular waves were examined. To validate and verify the coupled numerical method, the simulation results were compared to the measurements from a wave tank test and a commercial code (OrcaFlex). Second, a coupled model was built to simulate a two-body point absorber system with a chain-connected catenary system. The influence of the mooring connection on the point absorber was investigated. Overall, the study showed that the coupling of WEC-Sim and the MoorDyn model works reasonably well for simulating a floating system with practical mooring designs and predicting the corresponding dynamic loads on the mooring lines. Further analyses on improving coupling efficiency and the feasibility of applying the numerical method to simulate WEC systems with more complex mooring configuration are still needed.

  18. Thermal and optical aspects of glob-top design for phosphor converted white LED light sources

    NASA Astrophysics Data System (ADS)

    Sommer, Christian; Fulmek, Paul; Nicolics, Johann; Schweitzer, Susanne; Nemitz, Wolfgang; Hartmann, Paul; Pachler, Peter; Hoschopf, Hans; Schrank, Franz; Langer, Gregor; Wenzl, Franz P.

    2013-09-01

    For a systematic approach to improve the white light quality of phosphor converted light-emitting diodes (LEDs) for general lighting applications it is imperative to get the individual sources of error for correlated color temperature (CCT) reproducibility and maintenance under control. In this regard, it is of essential importance to understand how geometrical, optical and thermal properties of the color conversion elements (CCE), which typically consist of phosphor particles embedded in a transparent matrix material, affect the constancy of a desired CCT value. In this contribution we use an LED assembly consisting of an LED die mounted on a printed circuit board by chip-on-board technology and a CCE with a glob-top configuration on the top of it as a model system and discuss the impact of the CCE shape and size on CCT constancy with respect to substrate reflectivity and thermal load of the CCEs. From these studies, some general conclusions for improved glob-top design can be drawn.

  19. Design, processing, and testing of lsi arrays for space station

    NASA Technical Reports Server (NTRS)

    Lile, W. R.; Hollingsworth, R. J.

    1972-01-01

    The design of a MOS 256-bit Random Access Memory (RAM) is discussed. Technological achievements comprise computer simulations that accurately predict performance; aluminum-gate COS/MOS devices including a 256-bit RAM with current sensing; and a silicon-gate process that is being used in the construction of a 256-bit RAM with voltage sensing. The Si-gate process increases speed by reducing the overlap capacitance between gate and source-drain, thus reducing the crossover capacitance and allowing shorter interconnections. The design of a Si-gate RAM, which is pin-for-pin compatible with an RCA bulk silicon COS/MOS memory (type TA 5974), is discussed in full. The Integrated Circuit Tester (ICT) is limited to dc evaluation, but the diagnostics and data collecting are under computer control. The Silicon-on-Sapphire Memory Evaluator (SOS-ME, previously called SOS Memory Exerciser) measures power supply drain and performs a minimum number of tests to establish operation of the memory devices. The Macrodata MD-100 is a microprogrammable tester which has capabilities of extensive testing at speeds up to 5 MHz. Beam-lead technology was successfully integrated with SOS technology to make a simple device with beam leads. This device and the scribing are discussed.

  20. Design and fabrication of six-volt vertically-stacked GaAs photovoltaic power converter.

    PubMed

    Zhao, Yongming; Sun, Yurun; He, Yang; Yu, Shuzhen; Dong, Jianrong

    2016-11-30

    A six-volt vertically-stacked, high current GaAs photovoltaic power converter (PPC) has been designed and fabricated to produce output power over 1 W under monochromatic illumination. An N(++)-GaAs/P(++)-AlGaAs tunnel junctions (TJs) structure has been used for connecting each sub-cell in this vertically-stacked PPC device. The thickness of the each GaAs sub-cell has been derived based on the calculation of absorption depth of photons with a wavelength of 808 nm using absorption coefficient obtained from ellipsometry measurements. The devices were characterized under non-uniform CW laser illumination at 808 nm with incident power up to 4.1 W. A maximum conversion efficiency of 50.2% was achieved at 0.3 W under non-uniform (coupled in optical fiber) monochromatic illumination, dropping to 42.5% at 4.1 W. The operating voltage at the maximum power point is 5.5-6.0 V, depending on the incident laser power, and an output electrical power output of 1.3 W can be extracted at a laser power of 2.9 W and the maximum electrical power output amounts to 1.72 W. The external quantum efficiency (EQE) measurement indicates that the performance of PPC can be further improved by refining the design of the thickness of sub-cells and improving TJs.

  1. Design and fabrication of six-volt vertically-stacked GaAs photovoltaic power converter

    PubMed Central

    Zhao, Yongming; Sun, Yurun; He, Yang; Yu, Shuzhen; Dong, Jianrong

    2016-01-01

    A six-volt vertically-stacked, high current GaAs photovoltaic power converter (PPC) has been designed and fabricated to produce output power over 1 W under monochromatic illumination. An N++-GaAs/P++-AlGaAs tunnel junctions (TJs) structure has been used for connecting each sub-cell in this vertically-stacked PPC device. The thickness of the each GaAs sub-cell has been derived based on the calculation of absorption depth of photons with a wavelength of 808 nm using absorption coefficient obtained from ellipsometry measurements. The devices were characterized under non-uniform CW laser illumination at 808 nm with incident power up to 4.1 W. A maximum conversion efficiency of 50.2% was achieved at 0.3 W under non-uniform (coupled in optical fiber) monochromatic illumination, dropping to 42.5% at 4.1 W. The operating voltage at the maximum power point is 5.5–6.0 V, depending on the incident laser power, and an output electrical power output of 1.3 W can be extracted at a laser power of 2.9 W and the maximum electrical power output amounts to 1.72 W. The external quantum efficiency (EQE) measurement indicates that the performance of PPC can be further improved by refining the design of the thickness of sub-cells and improving TJs. PMID:27901079

  2. Design and fabrication of six-volt vertically-stacked GaAs photovoltaic power converter

    NASA Astrophysics Data System (ADS)

    Zhao, Yongming; Sun, Yurun; He, Yang; Yu, Shuzhen; Dong, Jianrong

    2016-11-01

    A six-volt vertically-stacked, high current GaAs photovoltaic power converter (PPC) has been designed and fabricated to produce output power over 1 W under monochromatic illumination. An N++-GaAs/P++-AlGaAs tunnel junctions (TJs) structure has been used for connecting each sub-cell in this vertically-stacked PPC device. The thickness of the each GaAs sub-cell has been derived based on the calculation of absorption depth of photons with a wavelength of 808 nm using absorption coefficient obtained from ellipsometry measurements. The devices were characterized under non-uniform CW laser illumination at 808 nm with incident power up to 4.1 W. A maximum conversion efficiency of 50.2% was achieved at 0.3 W under non-uniform (coupled in optical fiber) monochromatic illumination, dropping to 42.5% at 4.1 W. The operating voltage at the maximum power point is 5.5–6.0 V, depending on the incident laser power, and an output electrical power output of 1.3 W can be extracted at a laser power of 2.9 W and the maximum electrical power output amounts to 1.72 W. The external quantum efficiency (EQE) measurement indicates that the performance of PPC can be further improved by refining the design of the thickness of sub-cells and improving TJs.

  3. Design, synthesis and biological activity of novel non-peptidyl endothelin converting enzyme inhibitors, 1-phenyl-tetrazole-formazan analogues.

    PubMed

    Yamazaki, Kazuto; Hasegawa, Hirohiko; Umekawa, Kayo; Ueki, Yasuyuki; Ohashi, Naohito; Kanaoka, Masaharu

    2002-05-06

    A novel non-peptidyl endothelin converting enzyme inhibitor was obtained through a pharmacophore analysis of known inhibitors and three-dimensional structure database search. Analogues of the new inhibitor were designed using the structure-activity relationship of known inhibitors and synthesized. In anesthetized rats, intraperitoneal administration of the analogues suppressed the pressor responses induced by big endothelin-1.

  4. Space station integrated wall design and penetration damage control

    NASA Technical Reports Server (NTRS)

    Coronado, A. R.; Gibbins, M. N.; Wright, M. A.; Stern, P. H.

    1987-01-01

    A methodology was developed to allow a designer to optimize the pressure wall, insulation, and meteoroid/debris shield system of a manned spacecraft for a given spacecraft configuration and threat environment. The threat environment consists of meteoroids and orbital debris, as specified for an arbitrary orbit and expected lifetime. An overall probability of no penetration is calculated, as well as contours of equal threat that take into account spacecraft geometry and orientation. Techniques, tools, and procedures for repairing an impacted and penetrated pressure wall were developed and tested. These techniques are applied from the spacecraft interior and account for the possibility of performing the repair in a vacuum. Hypervelocity impact testing was conducted to: (1) develop and refine appropriate penetration functions, and (2) determine the internal effects of a penetration on personnel and equipment.

  5. Preliminary design of a cargo return vehicle for Space Station Freedom

    NASA Astrophysics Data System (ADS)

    Cook, Stephen; Vano, Andrew

    1990-09-01

    The design of an unmanned, reusable cargo return vehicle (CRV) incorporated as a class project at the University of Minnesota under NASA auspices is presented. Two configurations are considered, a winged and a biconic with a parafoil advanced recovery system. Three inline liquid rocket boosters would propel the CRV into a low earth orbit with onboard orbital maneuvering system engines used to reach station orbit and dock to the station. The main objective of the courses was to develop the design skills of the students while allowing them to work together in teams with NASA and industry engineers on a specific NASA project. The final conclusion of the study was that the winged CRV was the best vehicle for space station resupply.

  6. From 2001 to 1994: Political environment and the design of NASA's Space Station system

    NASA Technical Reports Server (NTRS)

    Fries, Sylvia Doughty

    1988-01-01

    The U.S. civilian space station, a hope of numerous NASA engineers since before the agency was founded in 1958 and promoted by NASA as the country's 'next logical step' into space, provides an excellent case study of the way public-sector research and development agencies continuously redefine new technologies in the absence of the market discipline that governs private-sector technological development. The number of space station design studies conducted since 1959, both internally by NASA or contracted by the agency to the aerospace industry, easily exceeds a hundred. Because of this, three clearly distinguishable examples are selected from the almost thirty-year history of space station design in NASA. Together these examples illustrate the difficulty of defining a new technological system in the public sector as that system becomes increasingly subject, for its development, to the vagaries of federal research and development politics.

  7. Design of the DFVLR 25 m wind energy converter and first operating results

    NASA Astrophysics Data System (ADS)

    Molly, J.-P.

    1984-12-01

    A wind energy converter, called Debra-25, has been developed jointly by the DFVLR (German Institute for Research and Experimentation in Aeronautics and Astronautics) and the Brazilian 'Centro Tecnico Aeroespacial' (CTA). The wind conditions at the coast in the northeastern part of Brazil are favorable for the operation of wind energy converters, while the existence of many small local electric power networks provides a suitable technological basis for the operation of such converters. Winds in the interior of the country, however, are less powerful than at the coast. It was, therefore, desirable to build a windmill which was adjustable to local wind conditions. Another objective was related to the possibility to be able to assemble and install the converter without heavy cranes. The Debra-25 has a rotor with a diameter of 25 m and provides a nominal electric power of 100 kW. The selected two-genertor concept is very suited for an operation at low wind pressure.

  8. Power Converter Control Algorithm Design and Simulation for the NREL Next-Generation Drivetrain: July 8, 2013 - January 7, 2016

    SciTech Connect

    Blodgett, Douglas; Behnke, Michael; Erdman, William

    2016-08-01

    The National Renewable Energy Laboratory (NREL) and NREL Next-Generation Drivetrain Partners are developing a next-generation drivetrain (NGD) design as part of a Funding Opportunity Announcement award from the U.S. Department of Energy. The proposed NGD includes comprehensive innovations to the gearbox, generator, and power converter that increase the gearbox reliability and drivetrain capacity, while lowering deployment and operation and maintenance costs. A key task within this development effort is the power converter fault control algorithm design and associated computer simulations using an integrated electromechanical model of the drivetrain. The results of this task will be used in generating the embedded control software to be utilized in the power converter during testing of the NGD in the National Wind Technology Center 2.5-MW dynamometer. A list of issues to be addressed with these algorithms was developed by review of the grid interconnection requirements of various North American transmission system operators, and those requirements that presented the greatest impact to the wind turbine drivetrain design were then selected for mitigation via power converter control algorithms.

  9. Design Methodology And Qualification Tests Results For A Highly Integrated And Space Qualified Point Of Load Converter

    NASA Astrophysics Data System (ADS)

    Vassal, Marie-Cecile; Dubus, Patrick; Fiant, Nicolas

    2011-10-01

    3D Plus developed a highly miniaturized and Space qualified Point of Load (POL) Converter to power modern fast digital electronics such as ASICs, FPGAs and Memory devices that require low voltages with a high precision regulation and excellent dynamic performances under large load transients. The POL Converter is hardened by design thanks to specific radiation effects mitigation techniques and space design de-rating rules. It is built with a space qualified 3D System-In-Package (SIP) technology and embeds 113 add-on parts spread over 3 stacked layers. Thanks to the unique 3D Plus technology, the device size is limited to 25 x 26.5 x 10 mm. This paper discuss the converter topology trade-offs and highlight some final design solutions implemented to achieve the best compromise between efficiency, dynamic performance, protection/flexibility and radiation hardening level. The product implementation and its electrical test results are presented. Also, the radiation hardening strategy, the Total Ionizing Dose (TID), Single Event Latch-up (SEL) and Single Event Effect (SEE) test methodology and the results are described. A special focus is done on SEE tests for which the POL Converter was rebuilt with "decap" add-on parts and exposed under the beam for detailed SEE behavior measurements.

  10. Design and development of repetitive capacitor charging power supply based on series-parallel resonant converter topology

    NASA Astrophysics Data System (ADS)

    Patel, Ankur; Nagesh, K. V.; Kolge, Tanmay; Chakravarthy, D. P.

    2011-04-01

    LCL resonant converter based repetitive capacitor charging power supply (CCPS) is designed and developed in the division. The LCL converter acts as a constant current source when switching frequency is equal to the resonant frequency. When both resonant inductors' values of LCL converter are same, it results in inherent zero current switching (ZCS) in switches. In this paper, ac analysis with fundamental frequency approximation of LCL resonant tank circuit, frequency dependent of current gain converter followed by design, development, simulation, and practical result is described. Effect of change in switching frequency and resonant frequency and change in resonant inductors ratio on CCPS will be discussed. An efficient CCPS of average output power of 1.2 kJ/s, output voltage 3 kV, and 300 Hz repetition rate is developed in the division. The performance of this CCPS has been evaluated in the laboratory by charging several values of load capacitance at various repetition rates. These results indicate that this design is very feasible for use in capacitor-charging applications.

  11. Design and development of repetitive capacitor charging power supply based on series-parallel resonant converter topology.

    PubMed

    Patel, Ankur; Nagesh, K V; Kolge, Tanmay; Chakravarthy, D P

    2011-04-01

    LCL resonant converter based repetitive capacitor charging power supply (CCPS) is designed and developed in the division. The LCL converter acts as a constant current source when switching frequency is equal to the resonant frequency. When both resonant inductors' values of LCL converter are same, it results in inherent zero current switching (ZCS) in switches. In this paper, ac analysis with fundamental frequency approximation of LCL resonant tank circuit, frequency dependent of current gain converter followed by design, development, simulation, and practical result is described. Effect of change in switching frequency and resonant frequency and change in resonant inductors ratio on CCPS will be discussed. An efficient CCPS of average output power of 1.2 kJ/s, output voltage 3 kV, and 300 Hz repetition rate is developed in the division. The performance of this CCPS has been evaluated in the laboratory by charging several values of load capacitance at various repetition rates. These results indicate that this design is very feasible for use in capacitor-charging applications.

  12. Concept design, modeling and station-keeping attitude control of an earth observation platform

    NASA Astrophysics Data System (ADS)

    Yang, Yueneng; Wu, Jie; Zheng, Wei

    2012-11-01

    The stratosphere airship provides a unique and promising platform for earth observation. Researches on the project design and control scheme for earth observation platforms are still rarely documented. Nonlinear dynamics, model uncertainties, and external disturbances contribute to the difficulty in maneuvering the stratosphere airship. A key technical challenge for the earth observation platform is station keeping, or the ability to remain fixed over a geo-location. This paper investigates the conceptual design, modeling and station-keeping attitude control of the near-space earth observation platform. A conceptual design of the earth observation platform is presented. The dynamics model of the platform is derived from the Newton-Euler formulation, and the station-keeping control system of the platform is formulated. The station-keeping attitude control approach for the platform is proposed. The multi-input multi-output nonlinear control system is decoupled into three single-input single-output linear subsystems via feedback linearization, the attitude controller design is carried out on the new linear systems using terminal sliding mode control, and the global stability of the closed-loop system is proven by using the Lyapunov theorem. The performance of the designed control system is simulated by using the variable step Runge-Kutta integrator. Simulation results show that the control system tracks the commanded attitude with an error of zero, which verify the effectiveness and robustness of the designed control system in the presence of parametric uncertainties. The near-space earth observation platform has several advantages over satellites, such as high resolution, fast to deploy, and convenient to retrieve, and the proposed control scheme provides an effective approach for station-keeping attitude control of the earth observation platform.

  13. A novel design approach for a neutron measurement station for burnt fuel

    NASA Astrophysics Data System (ADS)

    Dietler, Rodolfo; Hursin, Mathieu; Perret, Gregory; Jordan, Kelly; Chawla, Rakesh

    2012-11-01

    The design and characterization of a passive neutron measurement station for highly burnt fuel has been undertaken at the Paul Scherrer Institute (PSI). The measurement station aims at the determination of the total neutron emission rate of full-length light water reactor (LWR) fuel rods, as also the corresponding axial distributions. It is intended that the measurement station be introduced into the hot cells available at PSI to allow measuring the neutron emission of spent fuel rods provided by the Swiss nuclear power plants. In addition, the neutron emission of a large set of burnt fuel samples that have been previously characterized by post-irradiation examination (PIE) will be measured, in order to relate neutron emission to the burnup and isotopic composition of different fuel types. The design of the measurement station is presented in this article. A post-processing algorithm is introduced to improve the spatial resolution of the "measured" axial profile. In order to quantify the accuracy of the reconstructed neutron source distribution, a figure-of-merit (FOM) is defined and adapted to the detection procedure. With the optimized measurement station and procedure, it is estimated that the neutron emission distribution of a highly burnt, full-length fuel rod would be measurable with acceptable accuracy in about 20 min.

  14. Project EGRESS: The design of an assured crew return vehicle for the space station

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Keeping preliminary studies by NASA in mind, an Assured Crew Return Vehicle (ACRV) was developed. The system allows the escape of one or more crew members from Space Station Freedom in case of emergency. The design of the vehicle addresses propulsion, orbital operations, reentry, landing and recovery, power and communication, and life support. In light of recent modifications in Space Station design, Project EGRESS (Earthbound Guaranteed ReEntry from Space Station) pays particular attention to its impact on Space Station operations, interfaces and docking facilities, and maintenance needs. A water landing, medium lift vehicle was found to best satisfy project goals of simplicity and cost efficiency without sacrificing the safety and reliability requirements. With a single vehicle, one injured crew member could be returned to Earth with minimal pilot involvement. Since the craft is capable of returning up to five crew members, two such permanently docked vehicles would allow full evacuation of the Space Station. The craft could be constructed entirely with available 1990 technology and launched aboard a shuttle orbiter.

  15. An investigation of the needs and the design of an orbiting space station with growth capabilities

    NASA Technical Reports Server (NTRS)

    Dossey, J. R.; Trotti, G.

    1977-01-01

    An architectural approach to the evolutionary growth of an orbiting space station from a small manned satellite to a fully independent, self-sustainable space colony facility is presented. Social and environmental factors, ease of transportation via the space shuttle, and structural design are considered.

  16. Implications of Privacy Needs and Interpersonal Distancing Mechanisms for Space Station Design

    NASA Technical Reports Server (NTRS)

    Harrison, A. A.; Sommer, R.; Struthers, N.; Hoyt, K.

    1986-01-01

    The literature on privacy needs, personal space, interpersonal distancing, and crowding is reveiwed with special reference to spaceflight and spaceflight analogous conditions. A quantitative model is proposed for understanding privacy, interpersonal distancing, and performance. The implications for space station design is described.

  17. Mechanical design of a low concentration ratio solar array for a space station application

    NASA Technical Reports Server (NTRS)

    Biss, M. S.; Hsu, L.

    1983-01-01

    This paper describes a preliminary study and conceptual design of a low concentration ratio solar array for a space station application with approximately a 100 kW power requirement. The baseline design calls for a multiple series of inverted, truncated, pyramidal optical elements with a geometric concentration ratio (GCR) of 6. It also calls for low life cycle cost, simple on-orbit maintainability, 1984 technology readiness date, and gallium arsenide (GaAs) of silicon (Si) solar cell interchangeability. Due to the large area needed to produce the amount of power required for the baseline space station, a symmetrical wing design, making maximum use of the commonality of parts approach, was taken. This paper will describe the mechanical and structural design of a mass-producible solar array that is very easy to tailor to the needs of the individual user requirement.

  18. Truss Climbing Robot for Space Station: Design, Analysis, and Motion Control

    NASA Astrophysics Data System (ADS)

    Chung, Wing Kwong

    The application of space robots has become more popular in performing tasks such as Intra and Extra Vehicular Activities (EVA) in Low Earth Orbit. For EVA, space robots were always designed as a chain-like manipulator with a joint configuration similar to on the earth robotic arm. Based on their joint configuration, they can be classified into two main categories. The first one is the six degrees of freedom (DOF) robotic arm including Shuttle Remote Manipulator System (SRMS), Engineering Test Satellite No. 7 (ETS-VII), the Main Arm (MA) and the Small Fine Arm (SFA) of Module Remote Manipulator System (JEMRMS). The other group is the seven-DOF space robotic arm which includes European Robotic Arm (ERA) and Space Station Remote Manipulator System (SSRMS), or Canadarm2. They not only perform manipulation tasks, but also be able to navigate on the exterior of the International Space Station (ISS). In a free floating environment, motions of a space robotic arm cause the attitude change of a space station because of their dynamic coupling effect. Hence, the stabilization of the space station attitude is important to maintain the electrical energy generated by the solar panels and the signal strength for communication. Most of research in this area focuses on the motion control of a space manipulator through the study of Generalized Jacobian Matrix. Little research has been conducted specifically on the design of locomotion mechanism of a space manipulator. This dissertation proposes a novel methodology for the locomotion on a space station which aims to lower the disturbance on a space station. Without modifying the joint configuration of conventional space manipulators, the use of a new gripping mechanism is proposed which combines the advantages of active wheels and conventional grippers. To realize the proposed gripping mechanism, this dissertation also presents the design of a novel frame climbing robot (Frambot) which is equipped with the new gripping mechanism

  19. Multifunctional gold nanoparticles for targeted imaging of angiotensin converting enzyme design, characterization, and application

    NASA Astrophysics Data System (ADS)

    Ghann, William Emmanuel

    Cardiovascular diseases (CVD) are the leading cause of morbidity and mortality in the United States with approximately one in every three death being attributed to these diseases. The overarching problem with heart diseases is that once a person has suffered from an attack, there is a high likelihood of a recurrent attack. According to the American Heart Association, approximately 785,000 Americans per year suffer from heart attacks for the first time and about half of the aforementioned experience an ensuing attack. The second attack is often fatal, and therefore relapse prevention is crucial. One of the possible ways of averting the recurrence of such an attack is through the precise monitoring of the preceding biomarkers or risk indicators. This project encompasses the design, synthesis, characterization, and application of nanoparticle-based contrast agents that can potentially be used in the monitoring of the reemergence of a biomarker expressed after a person has suffered myocardial infarction. The overexpression of this biomarker, angiotensin converting enzyme (ACE), is also associated with development of cardiac and pulmonary fibrosis. To this end, highly concentrated gold nanoparticles have been synthesized and conjugated to Lisinopril, an ACE inhibitor, for the molecular imaging of ACE using X-ray CT. Various stabilities studies were conducted to verify the resistance of this gold nanoprobe in biological relevant media. They have also been successfully used in X-ray computed tomography to visualize tissue ACE and thus render them potentially versatile in the monitoring of cardiovascular diseases. An MRI tag was also conjugated to the gold nanoparticle affording the opportunity for bimodal imaging of ACE. This contrast agent could further be used for the quantification using K-edge CT of the relationship between the amount of the said marker and its role in predicting the possibility of a successive heart attack. The prepared nanoparticle-based contrast

  20. An intelligent control and virtual display system for evolutionary space station workstation design

    NASA Technical Reports Server (NTRS)

    Feng, Xin; Niederjohn, Russell J.; Mcgreevy, Michael W.

    1992-01-01

    Research and development of the Advanced Display and Computer Augmented Control System (ADCACS) for the space station Body-Ported Cupola Virtual Workstation (BP/VCWS) were pursued. The potential applications were explored of body ported virtual display and intelligent control technology for the human-system interfacing applications is space station environment. The new system is designed to enable crew members to control and monitor a variety of space operations with greater flexibility and efficiency than existing fixed consoles. The technologies being studied include helmet mounted virtual displays, voice and special command input devices, and microprocessor based intelligent controllers. Several research topics, such as human factors, decision support expert systems, and wide field of view, color displays are being addressed. The study showed the significant advantages of this uniquely integrated display and control system, and its feasibility for human-system interfacing applications in the space station command and control environment.

  1. Advanced EVA system design requirements study: EVAS/space station system interface requirements

    NASA Technical Reports Server (NTRS)

    Woods, T. G.

    1985-01-01

    The definition of the Extravehicular Activity (EVA) systems interface requirements and accomodations for effective integration of a production EVA capability into the space station are contained. A description of the EVA systems for which the space station must provide the various interfaces and accomodations are provided. The discussion and analyses of the various space station areas in which the EVA interfaces are required and/or from which implications for EVA system design requirements are derived, are included. The rationale is provided for all EVAS mechanical, fluid, electrical, communications, and data system interfaces as well as exterior and interior requirements necessary to facilitate EVA operations. Results of the studies supporting these discussions are presented in the appendix.

  2. Design, construction and utilization of a space station assembled from 5-meter erectable struts

    NASA Technical Reports Server (NTRS)

    Mikulas, M. M., Jr.; Bush, H. G.

    1986-01-01

    Presented are the primary characteristics of the 5-meter erectable truss designated for the space station. The relatively large 5-meter truss dimension was chosen to provide a deep beam for high bending stiffness yet provide convenient mounting locations for space shuttle cargo bay size payloads which are 14.5 ft. (4.4 m) in diameter. Truss nodes and quick-attachment erectable joints are described which provide for evolutionary three-dimensional growth and for simple maintenance and repair. A mobile remote manipulator system is described which is provided to assist in station construction and maintenance. A discussion is also presented of the construction of the space station and the associated EVA time.

  3. Design and assembly sequence analysis of option 3 for CETF reference space station

    NASA Technical Reports Server (NTRS)

    Garrett, L. Bernard; Andersen, Gregory C.; Hall, John B., Jr.; Allen, Cheryl L.; Scott, A. D., Jr.; So, Kenneth T.

    1987-01-01

    A design and assembly sequence was conducted on one option of the Dual Keel Space Station examined by a NASA Critical Evaluation Task Force to establish viability of several variations of that option. A goal of the study was to produce and analyze technical data to support Task Force decisions to either examine particular Option 3 variations in more depth or eliminate them from further consideration. An analysis of the phasing assembly showed that use of an Expendable Launch Vehicle in conjunction with the Space Transportation System (STS) can accelerate the buildup of the Station and ease the STS launch rate constraints. The study also showed that use of an Orbital Maneuvering Vehicle on the first flight can significantly benefit Station assembly and, by performing Station subsystem functions, can alleviate the need for operational control and reboost systems during the early flights. In addition to launch and assembly sequencing, the study assessed stability and control, and analyzed node-packaging options and the effects of keel removal on the structural dynamics of the Station. Results of these analyses are presented and discussed.

  4. Impacting Space Station Freedom design with operations and safety requirements - An availability process

    NASA Technical Reports Server (NTRS)

    Garegnani, Jerry J.; Schondorf, Steven Y.

    1990-01-01

    The unusually long mission duration of Space Station Freedom leads to operations costs that have significant impacts on life-cycle cost relative to previous manned space programs. Maintaining an affordable program requires that operations costs be considered throughout the design process. An appropriate means of impacting the design with operations concerns is to specify requirements that ensure operational effectiveness when implemented. The Space Station Freedom Program has developed a process defining such requirements. It focuses on specifying functional profiles and allocating resources such that designers gain a better understanding of the operational envelope in which their systems must perform. This paper examines the details of the process, where it came from, and why it is effective.

  5. Multi-stage design of an optimal momentum management controller for the Space Station

    NASA Technical Reports Server (NTRS)

    Sunkel, J. W.; Shieh, L. S.

    1990-01-01

    This paper presents a multistage design scheme for determining an optimal control-moment-gyro momentum-management and attitude-control system for the Space Station Freedom. The Space Station equations of motion are linearized and block-decomposed into two block-decoupled subsystems using the matrix-sign algorithm. A sequential procedure is utilized for designing a linear-quadratic regulator for each subsystem, which optimally places the eigenvalues of the closed-loop subsystem in the region of an open sector, bounded by lines inclined at + or - pi/2k (for k = 2 or 3) from the negative real axis, and the left-hand side of a line parallel to the imaginary axis in the s-plane. Simulation results are presented to compare the resultant designs.

  6. Bio-Medical Factors and External Hazards in Space Station Design

    NASA Technical Reports Server (NTRS)

    Olling, E. H.

    1966-01-01

    The design of space-station configurations is influenced by many factors. Probably the most demanding and critical are the biomedical and external hazards requirements imposed to provide the proper environment and supporting facilities for the crew and the adequate protective measures necessary to provide a configuration'in which the crew can live and work efficiently in relative comfort and safety. The major biomedical factors, such as physiology, psychology, nutrition, personal hygiene, waste management, and recreation, all impose their own peculiar requirements. The commonality and integration of these requirements demand the utmost ingenuity and inventiveness be exercised in order to achieve effective configuration compliance. The relationship of biomedical factors for the internal space-station environment will be explored with respect to internal atmospheric constituency, atmospheric pressure levels, oxygen positive pressure, temperature, humidity, CO2 concentration, and atmospheric contamination. The range of these various parameters and the recommended levels for design use will be analyzed. Requirements and criteria for specific problem areas such as zero and artificial gravity and crew private quarters will be reviewed and the impact on the design of representative solutions will be presented. In the areas of external hazards, the impact of factors such as meteoroids, radiation, vacuum, temperature extremes, and cycling on station design will be evaluated. Considerations with respect to operational effectiveness and crew safety will be discussed. The impact of such factors on spacecraft design to achieve acceptable launch and reentry g levels, crew rotation intervals, etc., will be reviewed.

  7. Spaceborne computer executive routine functional design specification. Volume 2: Computer executive design for space station/base

    NASA Technical Reports Server (NTRS)

    Kennedy, J. R.; Fitzpatrick, W. S.

    1971-01-01

    The computer executive functional system design concepts derived from study of the Space Station/Base are presented. Information Management System hardware configuration as directly influencing the executive design is reviewed. The hardware configuration and generic executive design requirements are considered in detail in a previous report (System Configuration and Executive Requirements Specifications for Reusable Shuttle and Space Station/Base, 9/25/70). This report defines basic system primitives and delineates processes and process control. Supervisor states are considered for describing basic multiprogramming and multiprocessing systems. A high-level computer executive including control of scheduling, allocation of resources, system interactions, and real-time supervisory functions is defined. The description is oriented to provide a baseline for a functional simulation of the computer executive system.

  8. Design of a KA-Band Image Rejection Sub-Harmonic Down-Converter MMIC

    NASA Astrophysics Data System (ADS)

    Liu, Yu; Yang, Tao; Yang, Ziqiang

    2010-12-01

    A Ka band image rejection sub-harmonic down-converter monolithic microwave integrated circuit (MMIC) is proposed. It contains a radio frequency (RF) amplifier, a broadband Lange coupler and two balanced mixers with two compact Marchand Baluns. The converter is fabricated by a commercial GaAs 0.2 μm pseudomorphic high electron mobility transistor (pHEMT) process, the size of which is 1.5 mm × 2 mm. Moreover, an improved nonlinear stability analysis method is presented in this paper. Based on the auxiliary generator (AG) technology, the method can analyze the nonlinear stability of circuits under the terminal impedance mismatched condition by setting the terminal load impedances as optimized variables. This method is applied to the sub-harmonic down-converter and is validated by the simulation and experiment. Experimental results show that from 30 GHz to 40 GHz, the conversion loss (CL) of the converter is less than 10 dB, and the image refection ratio (IMRR) is more than 15 dB.

  9. A novel design of DC-AC electrical machine rotary converter for hybrid solar and wind energy applications

    NASA Astrophysics Data System (ADS)

    Mohammed, K. G.; Ramli, A. Q.; Amirulddin, U. A. U.

    2013-06-01

    This paper proposes the design of a new bi-directional DC-AC rotary converter machine to convert a d.c. voltage to three-phase voltage and vice-versa using a two-stage energy conversion machine. The rotary converter consists of two main stages which are combined into single frame. These two stages are constructed from three main electromagnetic components. The first inner electromagnetic component represents the input stage that enables the DC power generated by solar energy from photo-voltaic cells to be transformed by the second and third components electro-magnetically to produce multi-phase voltages at the output stage. At the same time, extra kinetic energy from wind, which is sufficiently available, can be added to existing torque on the second electromagnetic component. Both of these input energies will add up to the final energy generated at the output terminals. Therefore, the machine will be able to convert solar and wind energies to the output terminals simultaneously. If the solar energy is low, the available wind energy will be able to provide energy to the output terminals and at the same time charges the batteries which are connected as backup system. At this moment, the machine behaves as wind turbine. The energy output from the machine benefits from two energy sources which are solar and wind. At night when the solar energy is not available and also the load is low, the wind energy is able to charge the batteries and at the same time provides output electrical power to the remaining the load. Therefore, the proposed system will have high usage of available renewable energy as compared to separated wind or solar systems. MATLAB codes are used to calculate the required dimensions, the magnetic and electrical circuits parameters to design of the new bi-directional rotary converter machine.

  10. DESIGNING AN OPPORTUNITY FUEL WITH BIOMASS AND TIRE-DERIVED FUEL FOR COFIRING AT WILLOW ISLAND GENERATING STATION AND COFIRING SAWDUST WITH COAL AT ALBRIGHT GENERATING STATION

    SciTech Connect

    K. Payette; D. Tillman

    2003-10-01

    During the period July 1, 2003-September 30, 2003, Allegheny Energy Supply Co., LLC (Allegheny) proceeded with demonstration operations at the Willow Island Generating Station and improvements to the Albright Generating Station cofiring systems. The demonstration operations at Willow Island were designed to document integration of bio mass cofiring into commercial operations, including evaluating new sources of biomass supply. The Albright improvements were designed to increase the resource base for the projects, and to address issues that came up during the first year of operations. During this period, a major presentation summarizing the program was presented at the Pittsburgh Coal Conference. This report summarizes the activities associated with the Designer Opportunity Fuel program, and demonstrations at Willow Island and Albright Generating Stations.

  11. A Fixed Telescopic Prosthesis Designed to Retrieve and Convert to Fixed-Removable Combination Case: A Clinical Report

    PubMed Central

    Panagiota, Spyropoulou; Polyzois, Gregory

    2015-01-01

    This clinical report describes a fixed maxillary telescopic dental prosthesis (FTDP) employing milled base metal copings and a metal superstructure veneered with composite resin, for the restoration in a periodontally compromised patient with uncontrolled diabetes. The telescopic prosthesis framework design incorporated occlusal rest seats in key positions along the arch in case of future posterior tooth loss, in order to be converted to fixed - removable combination prosthesis. The mandible was restored with a conventional fixed ceramo-metal dental prosthesis. PMID:27688397

  12. Space Station Furnace Facility. Volume 2: Requirements definition and conceptual design study

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The Space Station Freedom Furnace (SSFF) Project is divided into two phases: phase 1, a definition study phase, and phase 2, a design and development phase. TBE was awarded a research study entitled, 'Space Station Furnace Facility Requirements Definition and Conceptual Design Study' on June 2, 1989. This report addresses the definition study phase only. Phase 2 is to be complete after completion of phase 1. The contract encompassed a requirements definition study and culminated in hardware/facility conceptual designs and hardware demonstration development models to test these conceptual designs. The study was divided into two parts. Part 1 (the basic part of the effort) encompassed preliminary requirements definition and assessment; conceptional design of the SSFF Core; fabrication of mockups; and preparation for the support of a conceptional design review (CoDR). Part 2 (the optional part of the effort) included detailed definition of the engineering and design requirements, as derived from the science requirements; refinement of the conceptual design of the SSFF Core; fabrication and testing of the 'breadboards' or development models; and preparation for and support of a requirements definition review.

  13. A Design of a New Column-Parallel Analog-to-Digital Converter Flash for Monolithic Active Pixel Sensor.

    PubMed

    Chakir, Mostafa; Akhamal, Hicham; Qjidaa, Hassan

    2017-01-01

    The CMOS Monolithic Active Pixel Sensor (MAPS) for the International Linear Collider (ILC) vertex detector (VXD) expresses stringent requirements on their analog readout electronics, specifically on the analog-to-digital converter (ADC). This paper concerns designing and optimizing a new architecture of a low power, high speed, and small-area 4-bit column-parallel ADC Flash. Later in this study, we propose to interpose an S/H block in the converter. This integration of S/H block increases the sensitiveness of the converter to the very small amplitude of the input signal from the sensor and provides a sufficient time to the converter to be able to code the input signal. This ADC is developed in 0.18 μm CMOS process with a pixel pitch of 35 μm. The proposed ADC responds to the constraints of power dissipation, size, and speed for the MAPS composed of a matrix of 64 rows and 48 columns where each column ADC covers a small area of 35 × 336.76 μm(2). The proposed ADC consumes low power at a 1.8 V supply and 100 MS/s sampling rate with dynamic range of 125 mV. Its DNL and INL are 0.0812/-0.0787 LSB and 0.0811/-0.0787 LSB, respectively. Furthermore, this ADC achieves a high speed more than 5 GHz.

  14. Prefocal station mechanical design concept study for the E-ELT

    NASA Astrophysics Data System (ADS)

    Jolley, Paul; Brunetto, Enzo; Frank, Christoph; Lewis, Steffan; Marchetti, Enrico

    2016-07-01

    The Nasmyth platforms of the E-ELT will contain one Prefocal Station (PFS) each. The main PFS functional requirements are to provide a focal plane to the three Nasmyth focal stations and the Coudé focus, optical sensing supporting telescope low order optimisation and seeing limited image quality, and optical sensing supporting characterising and phasing of M1 and other telescope subsystems. The PFS user requirements are used to derive the PFS technical requirements specification that will form the basis for design, development and production of the system. This specification process includes high-level architectural decisions and technical performance budget allocations. The mechanical design concepts reported here have been developed in order to validate key system specifications and associated technical budgets.

  15. Design and Performance Evaluation of a 200 deg C Interleaved Boost Converter (Preprint)

    DTIC Science & Technology

    2012-09-01

    were measured under heated chamber conditions . Load and input powers were measured at the chamber entry/exit lugs. The converter efficiency as a...200 V, 1.85 kW case. As seen from the individual boost leg power dissipation columns in Table III, a slightly unbalanced current condition between...instrumentation and localized drive electronics for oil and gas recovery), and aircraft and spacecraft (turbine engines, motor drives, and space

  16. The Space Station Freedom Flight Telerobotic Servicer: the design and evolution of a dexterous space robot

    NASA Technical Reports Server (NTRS)

    McCain, H. G.; Andary, J. F.; Hewitt, D. R.; Haley, D. C.

    1991-01-01

    The Flight Telerobotic Servicer (FTS) Project at the Goddard Space Flight Center is developing an advanced telerobotic system to assist in and reduce crew extravehicular activity (EVA) for Space Station) Freedom (SSF). The FTS will provide a telerobotic capability to the Freedom Station in the early assembly phases of the program and will be employed for assembly, maintenance, and inspection applications throughout the lifetime of the space station. Appropriately configured elements of the FTS will also be employed for robotic manipulation in remote satellite servicing applications and possibly the Lunar/Mars Program. In mid-1989, the FTS entered the flight system design and implementation phase (Phase C/D) of development with the signing of the FTS prime contract with Martin Marietta Astronautics Group in Denver, Colorado. The basic FTS design is now established and can be reported on in some detail. This paper will describe the FTS flight system design and the rationale for the specific design approaches and component selections. The current state of space technology and the nature of the FTS task dictate that the FTS be designed with sophisticated teleoperation capabilities for its initial primary operating mode. However, there are technologies, such as advanced computer vision and autonomous planning techniques currently in research and advanced development phases which would greatly enhance the FTS capabilities to perform autonomously in less structured work environments. Therefore, a specific requirement on the initial FTS design is that it has the capability to evolve as new technology becomes available. This paper will describe the FTS design approach for evolution to more autonomous capabilities. Some specific task applications of the FTS and partial automation approaches of these tasks will also be discussed in this paper.

  17. Design and development of a Space Station proximity operations research and development mockup

    NASA Technical Reports Server (NTRS)

    Haines, Richard F.

    1986-01-01

    Proximity operations (Prox-Ops) on-orbit refers to all activities taking place within one km of the Space Station. Designing a Prox-Ops control station calls for a comprehensive systems approach which takes into account structural constraints, orbital dynamics including approach/departure flight paths, myriad human factors and other topics. This paper describes a reconfigurable full-scale mock-up of a Prox-Ops station constructed at Ames incorporating an array of windows (with dynamic star field, target vehicle(s), and head-up symbology), head-down perspective display of manned and unmanned vehicles, voice- actuated 'electronic checklist', computer-generated voice system, expert system (to help diagnose subsystem malfunctions), and other displays and controls. The facility is used for demonstrations of selected Prox-Ops approach scenarios, human factors research (work-load assessment, determining external vision envelope requirements, head-down and head-up symbology design, voice synthesis and recognition research, etc.) and development of engineering design guidelines for future module interiors.

  18. Converting a C-130 Hercules into a Compound Helicopter: A Conceptual Design Study

    NASA Technical Reports Server (NTRS)

    Kottapalli, Anjaney P.; Harris, Franklin D.

    2010-01-01

    This study presents the performance and weight changes for a Compound C-130 as compared to the Baseline C-130H Hercules, using NDARC as the primary analysis tool. First, the C-130H was modeled within NDARC, from which performance at various conditions and a parametric weight statement were generated. Then, the C-130H NDARC file was modified to represent the Compound C-130, which was then put through the same performance analysis as the C-130H. A parametric weight statement was also calculated for the Compound C-130, which allowed for comparison to the C-130H. As part of the modeling of the Compound C-130, a Rotor Design Spreadsheet was created that would allow the direct calculation of the weight of the main rotors being added. Using composite materials led to considerable weight savings for both the rotor system and the hub weights. These weight savings are reflected in the NDARC Technology Factors which were determined to be 0.71 and 0.5 for the rotor blades and the hub/hinge system, respectively. Such Technology Factors suggest that using composites for other components could drastically lighten the Operating Empty Weight of the aircraft. The weight statements show the weights for each of the components on each aircraft. It is quite evident that the Compound C-130 has a higher Operating Empty Weight due to the addition of the two main rotors and a drive system to connect each engine group on the wing tips. Upon further analysis, the main weight driver is the drive system. While the main rotor/hub/hinge weight increase is to be expected, the weight increase due to the transmission drive and gear boxes are cause for concern. Unless a method can be found of reducing the weight of the drive system, the weight penalty makes the Compound a C-130 an inefficient aircraft in terms of payload/fuel capacity. Possible solutions are either off-loading some of the power requirements through the drive system or using composite materials in the construction of the drive system

  19. Development of a physically-based planar inductors VHDL-AMS model for integrated power converter design

    NASA Astrophysics Data System (ADS)

    Ammouri, Aymen; Ben Salah, Walid; Khachroumi, Sofiane; Ben Salah, Tarek; Kourda, Ferid; Morel, Hervé

    2014-05-01

    Design of integrated power converters needs prototype-less approaches. Specific simulations are required for investigation and validation process. Simulation relies on active and passive device models. Models of planar devices, for instance, are still not available in power simulator tools. There is, thus, a specific limitation during the simulation process of integrated power systems. The paper focuses on the development of a physically-based planar inductor model and its validation inside a power converter during transient switching. The planar inductor model remains a complex device to model, particularly when the skin, the proximity and the parasitic capacitances effects are taken into account. Heterogeneous simulation scheme, including circuit and device models, is successfully implemented in VHDL-AMS language and simulated in Simplorer platform. The mixed simulation results has been favorably tested and compared with practical measurements. It is found that the multi-domain simulation results and measurements data are in close agreement.

  20. Thermal Control Subsystem Design for the Avionics of a Space Station Payload

    NASA Technical Reports Server (NTRS)

    Moran, Matthew E.

    1996-01-01

    A case study of the thermal control subsystem development for a space based payload is presented from the concept stage through preliminary design. This payload, the Space Acceleration Measurement System 2 (SAMS-2), will measure the acceleration environment at select locations within the International Space Station. Its thermal control subsystem must maintain component temperatures within an acceptable range over a 10 year life span, while restricting accessible surfaces to touch temperature limits and insuring fail safe conditions in the event of loss of cooling. In addition to these primary design objectives, system level requirements and constraints are imposed on the payload, many of which are driven by multidisciplinary issues. Blending these issues into the overall system design required concurrent design sessions with the project team, iterative conceptual design layouts, thermal analysis and modeling, and hardware testing. Multiple tradeoff studies were also performed to investigate the many options which surfaced during the development cycle.

  1. A novel design project for space solar power station (SSPS-OMEGA)

    NASA Astrophysics Data System (ADS)

    Yang, Yang; Zhang, Yiqun; Duan, Baoyan; Wang, Dongxu; Li, Xun

    2016-04-01

    The space solar power station (SSPS) capable of providing earth with primary power has been researched for 50 years. The SSPS is a tremendous design involving optics, mechanics, electromagnetism, thermology, control, and other disciplines. This paper presents a novel design project for SSPS named OMEGA. The space segment of the proposed GEO-based SSPS is composed of four main parts, such as spherical solar power collector, hyperboloid photovoltaic (PV) cell array, power management and distribution (PMAD) and microwave transmitting antenna. Principle of optics, structure configuration, wired and wireless power transmissions are presented.

  2. Analysis and design of a 10 to 30 kW grid-connected solar power system for the JPL fire station and first aid station

    NASA Technical Reports Server (NTRS)

    Josephs, R. H.

    1982-01-01

    The design and performance of a modestly sized utility-connected power conditioning system and its supporting photovoltaic collector are described and estimated. Utility preparations and guidelines to conform with the output of a small generating station with that of a large power network are examined.

  3. Subway platform air quality: Assessing the influences of tunnel ventilation, train piston effect and station design

    NASA Astrophysics Data System (ADS)

    Moreno, T.; Pérez, N.; Reche, C.; Martins, V.; de Miguel, E.; Capdevila, M.; Centelles, S.; Minguillón, M. C.; Amato, F.; Alastuey, A.; Querol, X.; Gibbons, W.

    2014-08-01

    A high resolution air quality monitoring campaign (PM, CO2 and CO) was conducted on differently designed station platforms in the Barcelona subway system under: (a) normal forced tunnel ventilation, and (b) with daytime tunnel ventilation systems shut down. PM concentrations are highly variable (6-128 μgPM1 m-3, 16-314 μgPM3 m-3, and 33-332 μgPM10 m-3, 15-min averages) depending on ventilation conditions and station design. Narrow platforms served by single-track tunnels are heavily dependent on forced tunnel ventilation and cannot rely on the train piston effect alone to reduce platform PM concentrations. In contrast PM levels in stations with spacious double-track tunnels are not greatly affected when tunnel ventilation is switched off, offering the possibility of significant energy savings without damaging air quality. Sampling at different positions along the platform reveals considerable lateral variation, with the greatest accumulation of particulates occurring at one end of the platform. Passenger accesses can dilute PM concentrations by introducing cleaner outside air, although lateral down-platform accesses are less effective than those positioned at the train entry point. CO concentrations on the platform are very low (≤1 ppm) and probably controlled by ingress of traffic-contaminated street-level air. CO2 averages range from 371 to 569 ppm, changing during the build-up and exchange of passengers with each passing train.

  4. Design and early development of a UAV terminal and a ground station for laser communications

    NASA Astrophysics Data System (ADS)

    Carrasco-Casado, Alberto; Vergaz, Ricardo; Sánchez Pena, José M.

    2011-11-01

    A free-space laser communication system has been designed and partially developed as an alternative to standard RF links from UAV to ground stations. This project belongs to the SINTONIA program (acronym in Spanish for low environmental-impact unmanned systems), led by BR&TE (Boeing Research and Technology Europe) with the purpose of boosting Spanish UAV technology. A MEMS-based modulating retroreflector has been proposed as a communication terminal onboard the UAV, allowing both the laser transmitter and the acquisition, tracking and pointing subsystems to be eliminated. This results in an important reduction of power, size and weight, moving the burden to the ground station. In the ground station, the ATP subsystem is based on a GPS-aided two-axis gimbal for tracking and coarse pointing, and a fast steering mirror for fine pointing. A beacon-based system has been designed, taking advantage of the retroreflector optical principle, in order to determine the position of the UAV in real-time. The system manages the laser power in an optimal way, based on a distance-dependent beam-divergence control and by creating two different optical paths within the same physical path using different states of polarization.

  5. Implications of privacy needs and interpersonal distancing mechanisms for space station design

    NASA Technical Reports Server (NTRS)

    Harrison, Albert A.; Sommer, Robert; Struthers, Nancy; Hoyt, Kathleen

    1988-01-01

    Isolation, confinement, and the characteristics of microgravity will accentuate the need for privacy in the proposed NASA space station, yet limit the mechanism available for achieving it. This study proposes a quantitative model for understanding privacy, interpersonal distancing, and performance, and discusses the practical implications for Space Station design. A review of the relevant literature provided the basis for a database, definitions of physical and psychological distancing, loneliness, and crowding, and a quantitative model of situational privacy. The model defines situational privacy (the match between environment and task), and focuses on interpersonal contact along visual, auditory, olfactory, and tactile dimensions. It involves summing across pairs of crew members, contact dimensions, and time, yet also permits separate analyses of subsets of crew members and contact dimensions. The study concludes that performance will benefit when the type and level of contact afforded by the environment align with that required by the task. The key to achieving this is to design a flexible, definable, and redefinable interior environment that provides occupants with a wide array of options to meet their needs for solitude, limited social interaction, and open group activity. The report presents 49 recommendations in five categories to promote a wide range of privacy options despite the space station's volumetric limitations.

  6. Bio-Medical Factors and External Hazards in Space Station Design

    NASA Technical Reports Server (NTRS)

    Olling, Edward H.

    1966-01-01

    The design of space-station configurations is influenced by many factors, Probably the most demanding and critical are the biomedical and external hazards requirements imposed to provide the proper environment and supporting facilities for the crew and the adequate protective measures necessary to provide a configuration in which the crew can live and work efficiently in relative comfort and safety. The major biomedical factors, such as physiology, psychology, nutrition, personal hygiene, waste management, and recreation, all impose their own peculiar requirements. The commonality and integration of these requirements demand the utmost ingenuity and inventiveness be exercised in order to achieve effective configuration compliance. The relationship of biomedical factors for the internal space-station environment will be explored with respect to internal atmospheric constituency, atmospheric pressure levels, oxygen positive pressure, temperature, humidity, CO2 concentration, and atmospheric contamination. The range of these various parameters and the recommended levels for design use will be analyzed. Requirements and criteria for specific problem areas such as zero and artificial gravity and crew private quarters will be reviewed and the impact on the design of representative solutions will be presented. In the areas of external hazards, the impact of factors such as meteoroids, radiation, vacuum, temperature extremes, and cycling on station design will be evaluated. Considerations with respect to operational effectiveness and crew safety will be discussed. The impact of such factors on spacecraft design to achieve acceptable launch and reentry g levels, crew rotation intervals, etc., will be reviewed. Examples of configurations, subsystems, and internal a arrangement and installations to comply with such biomedical factor requirements will ber presented. The effects of solutions to certain biomedical factors on configuration weight, operational convenience, and

  7. Preliminary analysis and design optimization of the short spacer truss of Space Station Freedom

    NASA Technical Reports Server (NTRS)

    Gendy, A. S.; Patnaik, S. N.; Hopkins, D. A.; Berke, L.

    1993-01-01

    The analysis, dynamic simulation, and design optimization of the short spacer truss of the Space Station Freedom are presented in this report. The short spacer truss will be positioned between the integrated equipment assembly (IEA) and another truss, called the long spacer truss, in the Space Station Freedom. During its launch in the Space Shuttle, the truss will be subjected to considerable in-span distributed inertia loads due to shuttle accelerations. The short spacer truss, therefore, has been modeled as a space frame to account for flexural response. Several parameters have been assumed, since the design specifications are in the process of development; hence the results presented should be considered preliminary. However, the automated analysis and design capabilities that have been developed can readily be used to generate an optimum design of the short spacer truss once the actual specifications have been determined. This report includes static and dynamic analyses of the short spacer truss, which have been obtained with the linear elastic code LE-HOST (in these analyses, LE-HOST data files have been automated to facilitate their future use for different design specifications of the short spacer truss); the dynamic animation of the short spacer truss, which has been carried out by using the results of the dynamic analysis and a post-processing feature of the modeling code PATRAN; and the optimum-weight design of the spacer truss, which was obtained under prescribed stress, displacement, and frequency constraints by using the design code COMETBOARDS. Examination of the analysis and design results revealed that the design could be improved if the configuration of the short spacer truss were modified to a certain extent. A modified configuration, which may simplify fabrication, has been suggested. The performance of this configuration has been evaluated and was found to be satisfactory under both static and dynamic conditions.

  8. Preliminary Design of a Galactic Cosmic Ray Shielding Materials Testbed for the International Space Station

    NASA Technical Reports Server (NTRS)

    Gaier, James R.; Berkebile, Stephen; Sechkar, Edward A.; Panko, Scott R.

    2012-01-01

    The preliminary design of a testbed to evaluate the effectiveness of galactic cosmic ray (GCR) shielding materials, the MISSE Radiation Shielding Testbed (MRSMAT) is presented. The intent is to mount the testbed on the Materials International Space Station Experiment-X (MISSE-X) which is to be mounted on the International Space Station (ISS) in 2016. A key feature is the ability to simultaneously test nine samples, including standards, which are 5.25 cm thick. This thickness will enable most samples to have an areal density greater than 5 g/sq cm. It features a novel and compact GCR telescope which will be able to distinguish which cosmic rays have penetrated which shielding material, and will be able to evaluate the dose transmitted through the shield. The testbed could play a pivotal role in the development and qualification of new cosmic ray shielding technologies.

  9. System requirements and design features of Space Station Remote Manipulator System mechanisms

    NASA Technical Reports Server (NTRS)

    Kumar, Rajnish; Hayes, Robert

    1991-01-01

    The Space Station Remote Manipulator System (SSRMS) is a long robotic arm for handling large objects/payloads on the International Space Station Freedom. The mechanical components of the SSRMS include seven joints, two latching end effectors (LEEs), and two boom assemblies. The joints and LEEs are complex aerospace mechanisms. The system requirements and design features of these mechanisms are presented. All seven joints of the SSRMS have identical functional performance. The two LEES are identical. This feature allows either end of the SSRMS to be used as tip or base. As compared to the end effector of the Shuttle Remote Manipulator System, the LEE has a latch and umbilical mechanism in addition to the snare and rigidize mechanisms. The latches increase the interface preload and allow large payloads (up to 116,000 Kg) to be handled. The umbilical connectors provide power, data, and video signal transfer capability to/from the SSRMS.

  10. Preliminary design of a satellite observation system for Space Station Freedom

    NASA Technical Reports Server (NTRS)

    Cabe, Greg (Editor); Gallagher, Chris; Wilson, Brian; Rehfeld, James; Maurer, Alexa; Stern, Dan; Nualart, Jaime; Le, Xuan-Trang

    1992-01-01

    Degobah Satellite Systems (DSS), in cooperation with the University Space Research Association (USRA), NASA - Johnson Space Center (JSC), and the University of Texas, has completed the preliminary design of a satellite system to provide inexpensive on-demand video images of all or any portion of Space Station Freedom (SSF). DSS has narrowed the scope of the project to complement the work done by Mr. Dennis Wells at Johnson Space Center. This three month project has resulted in completion of the preliminary design of AERCAM, the Autonomous Extravehicular Robotic Camera, detailed in this design report. This report begins by providing information on the project background, describing the mission objectives, constraints, and assumptions. Preliminary designs for the primary concept and satellite subsystems are then discussed in detail. Included in the technical portion of the report are detailed descriptions of an advanced imaging system and docking and safing systems that ensure compatibility with the SSF. The report concludes by describing management procedures and project costs.

  11. DESIGNING AN OPPORTUNITY FUEL WITH BIOMASS AND TIRE-DERIVED FUEL FOR COFIRING AT WILLOW ISLAND GENERATING STATION AND COFIRING SAWDUST WITH COAL AT ALBRIGHT GENERATING STATION

    SciTech Connect

    K. Payette; D. Tillman

    2001-10-01

    During the period July 1, 2001--September 30, 2001, Allegheny Energy Supply Co., LLC (Allegheny) continued construction of the Willow Island cofiring project, completed the installation of the fuel storage facility, the fuel receiving facility, and the processing building. All mechanical equipment has been installed and electrical construction has proceeded. During this time period significant short term testing of the Albright Generating Station cofiring facility was completed, and the 100-hour test was planned for early October. The testing demonstrated that cofiring at the Albright Generating Station could contribute to a ''4P Strategy''--reduction of SO{sub 2}, NO{sub x}, mercury, and greenhouse gas emissions. This report summarizes the activities associated with the Designer Opportunity Fuel program, and demonstrations at Willow Island and Albright Generating Stations. It details the construction activities at both sites along with the combustion modeling at the Willow Island site.

  12. Considerations for a design and operations knowledge support system for Space Station Freedom

    NASA Technical Reports Server (NTRS)

    Erickson, Jon D.; Crouse, Kenneth H.; Wechsler, Donald B.; Flaherty, Douglas R.

    1989-01-01

    Engineering and operations of modern engineered systems depend critically upon detailed design and operations knowledge that is accurate and authoritative. A design and operations knowledge support system (DOKSS) is a modern computer-based information system providing knowledge about the creation, evolution, and growth of an engineered system. The purpose of a DOKSS is to provide convenient and effective access to this multifaceted information. The complexity of Space Station Freedom's (SSF's) systems, elements, interfaces, and organizations makes convenient access to design knowledge especially important, when compared to simpler systems. The life cycle length, being 30 or more years, adds a new dimension to space operations, maintenance, and evolution. Provided here is a review and discussion of design knowledge support systems to be delivered and operated as a critical part of the engineered system. A concept of a DOKSS for Space Station Freedom (SSF) is presented. This is followed by a detailed discussion of a DOKSS for the Lyndon B. Johnson Space Center and Work Package-2 portions of SSF.

  13. A Design of a New Column-Parallel Analog-to-Digital Converter Flash for Monolithic Active Pixel Sensor

    PubMed Central

    Qjidaa, Hassan

    2017-01-01

    The CMOS Monolithic Active Pixel Sensor (MAPS) for the International Linear Collider (ILC) vertex detector (VXD) expresses stringent requirements on their analog readout electronics, specifically on the analog-to-digital converter (ADC). This paper concerns designing and optimizing a new architecture of a low power, high speed, and small-area 4-bit column-parallel ADC Flash. Later in this study, we propose to interpose an S/H block in the converter. This integration of S/H block increases the sensitiveness of the converter to the very small amplitude of the input signal from the sensor and provides a sufficient time to the converter to be able to code the input signal. This ADC is developed in 0.18 μm CMOS process with a pixel pitch of 35 μm. The proposed ADC responds to the constraints of power dissipation, size, and speed for the MAPS composed of a matrix of 64 rows and 48 columns where each column ADC covers a small area of 35 × 336.76 μm2. The proposed ADC consumes low power at a 1.8 V supply and 100 MS/s sampling rate with dynamic range of 125 mV. Its DNL and INL are 0.0812/−0.0787 LSB and 0.0811/−0.0787 LSB, respectively. Furthermore, this ADC achieves a high speed more than 5 GHz. PMID:28243628

  14. Dynamic systems behaviour analysis and design based on the qualitative theory of differential equations: the Boost power converter case

    NASA Astrophysics Data System (ADS)

    Llibre, Jaume; Spinetti-Rivera, Mario; Colina-Morles, Eliezer

    2015-06-01

    This paper uses the qualitative theory of differential equations to analyse/design the dynamic behaviour of control systems. In particular, the Poincaré compactification and the Poincaré--Hopf theorem are used for analysing the local dynamics near the finite and infinite equilibrium points. As an application, a large signal characterisation of a Boost type power converter in closed loop, including its equilibrium/bifurcation points and its global dynamics, which depends upon the value of the load resistance, is studied.

  15. Design and Operation of a 9-bit Single-flux-quantum Pulse-frequency Modulation Digital-to-analog Converter

    NASA Astrophysics Data System (ADS)

    Mizugaki, Yoshinao; Takahashi, Yoshitaka; Shimada, Hiroshi; Maezawa, Masaaki

    We designed and operated a 9-bit single-flux-quantum (SFQ) digital-to-analog converter (DAC). SFQ pulse-frequency modulation (PFM) was employed for generation of variable quantum output voltage, where a 9-bit variable pulse number multiplier and a 100-fold voltage multiplier were the key components. Test chips were fabricated using a Nb Josephson integration technology. Arbitrary voltage waveforms were synthesized with the maximum voltage of 2.54 mV. For ac voltage standard applications, relationships between the DAC resolution and the synthesized waveform frequency are discussed.

  16. Design of a high voltage input - output ratio dc-dc converter dedicated to small power fuel cell systems

    NASA Astrophysics Data System (ADS)

    Béthoux, O.; Cathelin, J.

    2010-12-01

    Consuming chemical energy, fuel cells produce simultaneously heat, water and useful electrical power [J.M. Andújar, F. Segura, Renew. Sust. Energy Rev. 13, 2309 (2009)], [J. Larminie, A. Dicks, Fuel Cell Systems Explained, 2nd edn. (John Wiley & Sons, 2003)]. As a matter of fact, the voltage generated by a fuel cell strongly depends on both the load power demand and the operating conditions. Besides, as a result of many design aspects, fuel cells are low voltage and high current electric generators. On the contrary, electric loads are commonly designed for small voltage swing and a high V/I ratio in order to minimize Joule losses. Therefore, electric loads supplied by fuel cells are typically fed by means of an intermediate power voltage regulator. The specifications of such a power converter are to be able to step up the input voltage with a high ratio (a ratio of 10 is a classic situation) and also to work with an excellent efficiency (in order to minimize its size, its weight and its losses) [A. Shahin, B. Huang, J.P. Martin, S. Pierfederici, B. Davat, Energy Conv. Manag. 51, 56 (2010)]. This paper deals with the design of this essential ancillary device. It intends to bring out the best structure for fulfilling this function. Several dc-dc converters with large voltage step-up ratios are introduced. A topology based on a coupled inductor or tapped inductor is closely studied. A detailed modelling is performed with the purpose of providing designing rules. This model is validated with both simulation and implementation. The experimental prototype is based on the following specifications: the fuel cell output voltage ranges from a 50 V open-voltage to a 25 V rated voltage while the load requires a constant 250 V voltage. The studied coupled inductor converter is compared with a classic boost converter commonly used in this voltage elevating application. Even though the voltage regulator faces severe FC specifications, the measured efficiency reaches 96% at the

  17. Feasibility study for convertible engine torque converter

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The feasibility study has shown that a dump/fill type torque converter has excellent potential for the convertible fan/shaft engine. The torque converter space requirement permits internal housing within the normal flow path of a turbofan engine at acceptable engine weight. The unit permits operating the engine in the turboshaft mode by decoupling the fan. To convert to turbofan mode, the torque converter overdrive capability bring the fan speed up to the power turbine speed to permit engagement of a mechanical lockup device when the shaft speed are synchronized. The conversion to turbofan mode can be made without drop of power turbine speed in less than 10 sec. Total thrust delivered to the aircraft by the proprotor, fan, and engine during tansient can be controlled to prevent loss of air speed or altitude. Heat rejection to the oil is low, and additional oil cooling capacity is not required. The turbofan engine aerodynamic design is basically uncompromised by convertibility and allows proper fan design for quiet and efficient cruise operation. Although the results of the feasibility study are exceedingly encouraging, it must be noted that they are based on extrapolation of limited existing data on torque converters. A component test program with three trial torque converter designs and concurrent computer modeling for fluid flow, stress, and dynamics, updated with test results from each unit, is recommended.

  18. Design of a delay-locked-loop-based time-to-digital converter

    NASA Astrophysics Data System (ADS)

    Zhaoxin, Ma; Xuefei, Bai; Lu, Huang

    2013-09-01

    A time-to-digital converter (TDC) based on a reset-free and anti-harmonic delay-locked loop (DLL) circuit for wireless positioning systems is discussed and described. The DLL that generates 32-phase clocks and a cycle period detector is employed to avoid “false locking". Driven by multiphase clocks, an encoder detects pulses and outputs the phase of the clock when the pulse arrives. The proposed TDC was implemented in SMIC 0.18 μm CMOS technology, and its core area occupies 0.7 × 0.55 mm2. The reference frequency ranges from 20 to 150 MHz. An LSB resolution of 521 ps can be achieved by using a reference clock of 60 MHz and the DNL is less than ±0.75 LSB. It dissipates 31.5 mW at 1.8 V supply voltage.

  19. Computer software design description for the Treated Effluent Disposal Facility (TEDF), Project L-045H, Operator Training Station (OTS)

    SciTech Connect

    Carter, R.L. Jr.

    1994-11-07

    The Treated Effluent Disposal Facility (TEDF) Operator Training Station (OTS) is a computer-based training tool designed to aid plant operations and engineering staff in familiarizing themselves with the TEDF Central Control System (CCS).

  20. Space Science Education with Mathematica: Interactive Design Modular Space Station Structures with Computer Algebra: Principles, Functional Units, Motions, Examples

    NASA Astrophysics Data System (ADS)

    Kabai, S.; Miyazaki, K.; Bérczi, Sz.

    2002-03-01

    We worked out a course with interactive Mathematica program to design Space Stations with icosahedral/dodecahedral tiling system of subunits, with motions for observing maneuvering space. Constraints/principles from geometry are also discussed.

  1. Analytical determination of space station response to crew motion and design of suspension system for microgravity experiments

    NASA Technical Reports Server (NTRS)

    Liu, F. C.

    1986-01-01

    The objective of this investigation is to make analytical determination of the acceleration produced by crew motion in an orbiting space station and define design parameters for the suspension system of microgravity experiments. A simple structural model for simulation of the IOC space station is proposed. Mathematical formulation of this model provides the engineers a simple and direct tool for designing an effective suspension system.

  2. Analytical determination of space station response to crew motion and design of suspension system for microgravity experiments

    NASA Technical Reports Server (NTRS)

    Liu, Frank C.

    1987-01-01

    The objective of this investigation is to make analytical determination of the acceleration produced by crew motion in an orbiting space station and define design parameters for the suspension system of microgravity experiments. A simple structural model for simulation of the IOC space station is proposed. Mathematical formulation of this model provides the engineers a simple and direct tool for designing an effective suspension system.

  3. Conceptual design of the Space Station polar platform thermal control subsystem

    NASA Astrophysics Data System (ADS)

    Bond, H. E.; Benko, D. J.; Chalmers, D. R.; Pergament, S. D.

    1989-07-01

    NASA's Space Station Freedom Program encompasses unmanned polar-orbiting platforms (POPs) in low-earth orbit (LEO) designed to support a variety of scientific and earth-observation missions. The platforms are modular in design, permitting in-orbit maintenance and replacement of limited-life subsystem and payload components. Such in-orbit servicing can extend the platform's useful life to 15 years or more, far exceeding that of a typical LEO spacecraft. The long life and modular design has forced a new approach to thermal control subsystem (TCS) design. The platforms's TCS must be readily adaptable to, and compatible with, the physical reconfiguration and resultant heat load changes. NASA has, in fact, identified thermal management as a critical factor in the overall platform design. A dual approach was used for the current polar platform TCS design. Platform thermal control is maintained using a distributed network of heat pipe panels, while payload thermal control is maintained via a centralized system of two-phase capillary pumped loops. This paper describes this baseline platform thermal design and the analytical tools used to validate the design concepts.

  4. Design tradeoffs for a Space Station solar-Brayton power system

    NASA Technical Reports Server (NTRS)

    Klann, J. L.; Staiger, P. J.

    1985-01-01

    Mass, area, and station-keeping propellant needs have been estimated for a typical system. And, although important criteria such as cost, Shuttle packaging, and erection/deployment schemes were not considered, the documented trends should aid in many of the design choices to be made. Effects on system characteristics were examined for: three heat storage salts with melting temperatures from 743 to 1121 K; parabolic and Cassegrainian mirrors; module power levels of 20 and 40 kW; and, alternate pumped-loop, tube-and-fin radiator configurations, with and without micrometeoroid armoring.

  5. Design of a 12 channel fm microwave receiver. [for satellite ground stations

    NASA Technical Reports Server (NTRS)

    Risch, C. O.; Rosenbaum, F. J.; Gregory, R. O.

    1974-01-01

    The design, fabrication, and performance of elements of a low cost FM microwave satellite ground station receiver is described. It is capable of accepting 12 contiguous color television equivalent bandwidth channels in the 11.72 to 12.2 GHz band. Each channel is 40 MHz wide and incorporates a 4 MHz guard band. The modulation format is wideband FM and the channels are frequency division multiplexed. Twelve independent CATV compatible baseband outputs are provided. The overall system specifications are first discussed, then consideration is given to the receiver subsystems and the signal branching network.

  6. Infrared fiber-optic fire sensors - Concepts and designs for Space Station applications

    NASA Technical Reports Server (NTRS)

    Tapphorn, Ralph M.; Porter, Alan R.

    1990-01-01

    Various design configurations used for testing IR fiber-optic (IFO) fire-sensor concepts are presented. Responsibility measurements conducted to select the best concept are reviewed. The results indicate that IFO fire-sensor systems based on distributed fiber sensors are feasible for future aerospace applications. For Space Station Freedom, these systems offer alternative fire detectors for monitoring areas within equipment or stage compartments where the ventilation may be inadequate for proper operation of smoke detectors. They also allow a large number of areas to be monitored by a single central detector unit, which reduces the associated cost and weight.

  7. Design study of large area 8 cm x 8 cm wrapthrough cells for space station

    NASA Technical Reports Server (NTRS)

    Garlick, George F. J.; Lillington, David R.

    1987-01-01

    The design of large area silicon solar cells for the projected NASA space station is discussed. It is based on the NASA specification for the cells which calls for an 8 cm by 8 cm cell of wrapthrough type with gridded back contacts. The beginning of life (BOL) power must be 1.039 watts per cell or larger and maximum end of life (EOL) after 10 years in the prescribed orbit under an equivalent 1MeV electron radiation damage fluence of 5 times 10 to the 13th power e/square cm. On orbit efficiency is to be optimized by a low thermal absorptance goal (thermal alpha) of .63.

  8. Energy storage and thermal control system design status. [for space station power supplies

    NASA Technical Reports Server (NTRS)

    Simons, Stephen N.; Willhoite, Bryan C.; Van Ommering, Gert

    1989-01-01

    The Space Station Freedom electric power system (EPS) will initially rely on photovoltaics for power generation and Ni/H2 batteries for electrical energy storage. The current design for the development status of two major subsystems in the PV Power Module is discussed. The energy storage subsystem comprised of high capacity Ni/H2 batteries and the single-phase thermal control system that rejects the excess heat generated by the batteries and other components associated with power generation andstorage is described.

  9. Conceptual design of pointing control systems for space station gimballed payloads

    NASA Technical Reports Server (NTRS)

    Hughes, Robert O.

    1986-01-01

    A conceptual design of the control system for Payload Pointing Systems (PPS) is developed using classic Proportional-Integral-Derivatives (PID) techniques. The major source of system pointing error is due to the disturbance-rich environment of the space station in the form of gimbal baseplate motions. These baseplate vibrations are characterized using Fast Fourier Transform (FFT) techniques. Both time domain and frequency domain dynamic models are developed to assess control system performance. Three basic methods exist for the improvement of PPS pointing performance: increase control system bandwidth, add Image Motion Compensation, and/or reduce (or change) the baseplate disturbance environment.

  10. User's design handbook for a Standardized Control Module (SCM) for DC to DC Converters, volume 2

    NASA Technical Reports Server (NTRS)

    Lee, F. C.

    1980-01-01

    A unified design procedure is presented for selecting the key SCM control parameters for an arbitrarily given power stage configuration and parameter values, such that all regulator performance specifications can be met and optimized concurrently in a single design attempt. All key results and performance indices, for buck, boost, and buck/boost switching regulators which are relevant to SCM design considerations are included to facilitate frequent references.

  11. Conceptual design and analysis of a dynamic scale model of the Space Station Freedom

    NASA Technical Reports Server (NTRS)

    Davis, D. A.; Gronet, M. J.; Tan, M. K.; Thorne, J.

    1994-01-01

    This report documents the conceptual design study performed to evaluate design options for a subscale dynamic test model which could be used to investigate the expected on-orbit structural dynamic characteristics of the Space Station Freedom early build configurations. The baseline option was a 'near-replica' model of the SSF SC-7 pre-integrated truss configuration. The approach used to develop conceptual design options involved three sets of studies: evaluation of the full-scale design and analysis databases, conducting scale factor trade studies, and performing design sensitivity studies. The scale factor trade study was conducted to develop a fundamental understanding of the key scaling parameters that drive design, performance and cost of a SSF dynamic scale model. Four scale model options were estimated: 1/4, 1/5, 1/7, and 1/10 scale. Prototype hardware was fabricated to assess producibility issues. Based on the results of the study, a 1/4-scale size is recommended based on the increased model fidelity associated with a larger scale factor. A design sensitivity study was performed to identify critical hardware component properties that drive dynamic performance. A total of 118 component properties were identified which require high-fidelity replication. Lower fidelity dynamic similarity scaling can be used for non-critical components.

  12. Feasibility, Design and Construction of a Small Hydroelectric Power Generation Station as a Student Design Project.

    ERIC Educational Resources Information Center

    Peterson, James N.; Hess, Herbert L.

    An undergraduate capstone engineering design project now provides hydroelectric power to a remote wilderness location. Students investigated the feasibility of designing, building, and installing a 4kW hydroelectric system to satisfy the need for electric power to support the research and teaching functions of Taylor Ranch, a university facility…

  13. Preliminary Verification and Validation of WEC-Sim, an Open-Source Wave Energy Converter Design Tool: Preprint

    SciTech Connect

    Ruehl, K.; Michelen, C.; Kanner, S.; Lawson, M.; Yu, Y. H.

    2014-03-01

    To promote and support the wave energy industry, a wave energy converter (WEC) design tool, WEC-Sim, is being developed by Sandia National Laboratories and the National Renewable Energy Laboratory. In this paper, the WEC-Sim code is used to model a point absorber WEC designed by the U.S. Department of Energy's reference model project. Preliminary verification was performed by comparing results of the WEC-Sim simulation through a code-to-code comparison, utilizing the commercial codes ANSYS-AQWA, WaveDyn, and OrcaFlex. A preliminary validation of the code was also performed by comparing WEC-Sim simulation results to experimental wave tank tests.

  14. Converting a C-130 Hercules into a Compound Helicopter: A Conceptual Design Study

    NASA Technical Reports Server (NTRS)

    Kottapalli, Anjaney P.; Harris, Franklin D.

    2012-01-01

    Currently, the US Military and NASA are investigating the feasibility of a Vertical/Short Take Off and Landing (VSTOL) aircraft that can provide invaluable aid in the combat theater and significantly improve the civil transportation system. The nominal military mission requirement calls for a 28-ton payload heavy lift capability while the civilian requirements calls for a 90-passenger, 1000-nm range, airliner, as noted in Reference 1. To aid in these aircraft requirements, the present study examined the conversion of a Lockheed Martin C-130 Hercules into a compound aircraft, which would demonstrate the technology required by a much larger version. The present study examined various configurations and rotor blade designs in order to fulfill the nominal mission described previously. It was shown that the initial design of a 180 ft diameter rotor to lift 155,000 lb was not feasible due to material constraints. A revised design, in which the rotor radius was reduced to 55 ft, met the given constraints but required too much power. The decision was made to move to a twin rotor compound to take advantage of the increased disc area and drop the need for anti torque devices. Following this design shift, a new design point was found where all five constraints were met and the power requirements were deemed reasonable. This twin-rotor design was used in NDARC to provide a complete sizing analysis of the chosen design point.

  15. International Space Station Evolution Data Book. Volume 1; Baseline Design; Revised

    NASA Technical Reports Server (NTRS)

    Jorgensen, Catherine A. (Editor); Antol, Jeffrey (Technical Monitor)

    2000-01-01

    The International Space Station (ISS) will provide an Earth-orbiting facility that will accommodate engineering experiments as well as research in a microgravity environment for life and natural sciences. The ISS will distribute resource utilities and support permanent human habitation for conducting this research and experimentation in a safe and habitable environment. The objectives of the ISS program are to develop a world-class, international orbiting laboratory for conducting high-value scientific research for the benefit of humans on Earth; to provide access to the microgravity environment; to develop the ability to live and work in space for extended periods; and to provide a research test bed for developing advanced technology for human and robotic exploration of space. The current design and development of the ISS has been achieved through the outstanding efforts of many talented engineers, designers, technicians, and support personnel who have dedicated their time and hard work to producing a state-of-the-art Space Station. Despite these efforts, the current design of the ISS has limitations that have resulted from cost and technology issues. Regardless, the ISS must evolve during its operational lifetime to respond to changing user needs and long-term national and international goals. As technologies develop and user needs change, the ISS will be modified to meet these demands. The design and development of these modifications should begin now to prevent a significant lapse in time between the baseline design and the realization of future opportunities. For this effort to begin, an understanding of the baseline systems and current available opportunities for utilization needs to be achieved. Volume I of this document provides the consolidated overview of the ISS baseline systems. It also provides information on the current facilities available for pressurized and unpressurized payloads. Information on current plans for crew availability and utilization

  16. Active dc filter for HVDC system--A test installation in the Konti-Skan DC link at Lindome converter station

    SciTech Connect

    Zhang, Wenyan; Asplund, G. . HVDC Division); Aberg, A. . Dept. of Man-Machine Communication); Jonsson, U. ); Loeoef, O. . Region Vaestsverige)

    1993-07-01

    The purpose of introducing active dc filters is to meet the more and more stringent requirement from power utilities on limiting telephone interference caused by harmonic currents from HVdc transmission lines, without unnecessarily increasing the cost of HVdc stations. An active dc filter installed in the Konti-Skan HVdc link is described. The active dc filter is connected at the bottom of an existing passive dc filter at the Lindome station. The active dc filter includes optic harmonic current measuring unit, control system, protection and supervision system, PWM power amplifier, high-frequency transformer, surge arrester, and coupling apparatuses. The active dc filter has small physical size and occupies small ground area. The performance of the active dc filter for eliminating the disturbing harmonics is excellent. To achieve comparable results by passive filters would require something like ten times more high voltage equipment.

  17. Converting Paper into Hardware: A Status of the TEMPO Instrument Design and Manufacturing

    NASA Astrophysics Data System (ADS)

    Nicks, D. K., Jr.; Flittner, D. E.; Chance, K.; Liu, X.; Al-Saadi, J. A.; Pennington, W. F.; Suleiman, R. M.; Rosenbaum, D. M.; Canova, B.; Baker, B.; Lasnik, J.

    2015-12-01

    The Tropospheric Emissions: Monitoring of Pollution (TEMPO) instrument is part of NASA's Earth Venture Instrument (EVI) program, and will be the first hosted payload sensor to make tropospheric gas observations from geostationary (GEO) orbit using an ultraviolet/visible spectrometer. The instrument is designed to provide key trace gas measurements important to understanding tropospheric air pollution chemistry. The baseline design measures ozone (O3), nitrogen dioxide (NO2), and formaldehyde (H2CO). The TEMPO instrument will provide hourly daylight measurements of these trace gases on urban-regional spatial scales. These remote sensing measurements augment current ground-based air quality measurements and will offer improvements in air quality modeling and prediction. The TEMPO project has completed its confirmation review as well as the Critical Design Review (CDR). The updated TEMPO design, instrument performance estimates and technical challenges will be presented.

  18. A computer modeling methodology and tool for assessing design concepts for the Space Station Data Management System

    NASA Technical Reports Server (NTRS)

    Jones, W. R.

    1986-01-01

    A computer modeling tool is being developed to assess candidate designs for the Space Station Data Management System (DMS). The DMS is to be a complex distributed computer system including the processor, storage devices, local area networks, and software that will support all processing functions onboard the Space Station. The modeling tool will allow a candidate design for the DMS, or for other subsystems that use the DMS, to be evaluated in terms of parameters. The tool and its associated modeling methodology are intended for use by DMS and subsystem designers to perform tradeoff analyses between design concepts using varied architectures and technologies.

  19. Conceptual design for the Space Station Freedom fluid physics/dynamics facility

    NASA Technical Reports Server (NTRS)

    Thompson, Robert L.; Chucksa, Ronald J.; Omalley, Terence F.; Oeftering, Richard C.

    1993-01-01

    A study team at NASA's Lewis Research Center has been working on a definition study and conceptual design for a fluid physics and dynamics science facility that will be located in the Space Station Freedom's baseline U.S. Laboratory module. This modular, user-friendly facility, called the Fluid Physics/Dynamics Facility, will be available for use by industry, academic, and government research communities in the late 1990's. The Facility will support research experiments dealing with the study of fluid physics and dynamics phenomena. Because of the lack of gravity-induced convection, research into the mechanisms of fluids in the absence of gravity will help to provide a better understanding of the fundamentals of fluid processes. This document has been prepared as a final version of the handout for reviewers at the Fluid Physics/Dynamics Facility Assessment Workshop held at Lewis on January 24 and 25, 1990. It covers the background, current status, and future activities of the Lewis Project Study Team effort. It is a revised and updated version of a document entitled 'Status Report on the Conceptual Design for the Space Station Fluid Physics/Dynamics Facility', dated January 1990.

  20. Space Station Furnace Facility. Volume 2: Requirements definition and conceptual design study. Appendix 3: Environment analysis

    NASA Technical Reports Server (NTRS)

    1992-01-01

    A Preliminary Safety Analysis (PSA) is being accomplished as part of the Space Station Furnace Facility (SSFF) contract. This analysis is intended to support SSFF activities by analyzing concepts and designs as they mature to develop essential safety requirements for inclusion in the appropriate specifications, and designs, as early as possible. In addition, the analysis identifies significant safety concerns that may warrant specific trade studies or design definition, etc. The analysis activity to date concentrated on hazard and hazard cause identification and requirements development with the goal of developing a baseline set of detailed requirements to support trade study, specifications development, and preliminary design activities. The analysis activity will continue as the design and concepts mature. Section 2 defines what was analyzed, but it is likely that the SSFF definitions will undergo further changes. The safety analysis activity will reflect these changes as they occur. The analysis provides the foundation for later safety activities. The hazards identified will in most cases have Preliminary Design Review (PDR) applicability. The requirements and recommendations developed for each hazard will be tracked to ensure proper and early resolution of safety concerns.

  1. Tampa Electric Company, Polk Power Station Unit No. 1, preliminary public design report

    SciTech Connect

    1994-06-01

    This preliminary Public Design Report (PDR) provides design information about Tampa Electric Company`s Polk Power Station Unit No. 1, which will demonstrate in a commercial 250 MW unit the benefits of the integration of oxygen-blown, entrained-flow coal gasification with advanced combined cycle technology. This project is partially funded by the US Department of Energy (DOE) under Round III of its Clean Coal Technology (CCT) Program under the provisions of Cooperative Agreement between DOE and Tampa Electric Company, novated on March 5,1992. The project is highlighted by the inclusion of a new hot gas cleanup system. DOE`s project management is based at its Morgantown Energy Technology Center (METC) in West Virginia. This report is preliminary, and the information contained herein is subject to revision. Definitive information will be available in the final PDR, which will be published at the completion of detailed engineering.

  2. Design and testing of the U.S. Space Station Freedom primary propulsion system

    NASA Technical Reports Server (NTRS)

    Morano, Joseph S.; Delventhal, Rex A.; Chilcot, Kimberly J.

    1992-01-01

    The primary propulsion system (PPS) for the Space Station Freedom is discussed in terms of salient design characteristics and key testing procedures. The rocket engine modules contain reboost and attitude control thrusters, and their designs are illustrated showing the mounting structures, thruster solenoid valves, and thrust chambers. The propellant tank assembly for storing gaseous N pressurant and hydrazine propellant is described as are the system avionics, thruster solenoid valves, and latching isolation valves. PPS testing conducted on the development systems includes the use of a propulsion-module development unit, a development test article, and system qualification testing. Specific test articles include functional heaters, mass/thermal simulated components, flight-quality structures, and software control operations.

  3. Design and testing of the U.S. Space Station Freedom primary propulsion system

    NASA Astrophysics Data System (ADS)

    Morano, Joseph S.; Delventhal, Rex A.; Chilcot, Kimberly J.

    1992-07-01

    The primary propulsion system (PPS) for the Space Station Freedom is discussed in terms of salient design characteristics and key testing procedures. The rocket engine modules contain reboost and attitude control thrusters, and their designs are illustrated showing the mounting structures, thruster solenoid valves, and thrust chambers. The propellant tank assembly for storing gaseous N pressurant and hydrazine propellant is described as are the system avionics, thruster solenoid valves, and latching isolation valves. PPS testing conducted on the development systems includes the use of a propulsion-module development unit, a development test article, and system qualification testing. Specific test articles include functional heaters, mass/thermal simulated components, flight-quality structures, and software control operations.

  4. Design and Initial Tests of the Tracker-Converter ofthe Gamma-ray Large Area Space Telescope

    SciTech Connect

    Atwood, W.B.; Bagagli, R.; Baldini, L.; Bellazzini, R.; Barbiellini, G.; Belli, F.; Borden, T.; Brez, A.; Brigida, M.; Caliandro, G.A.; Cecchi, C.; Cohen-Tanugi, J.; De Angelis, A.; Drell, P.; Favuzzi, C.; Fukazawa, Y.; Fusco, P.; Gargano, F.; Germani, S.; Giannitrapani, R.; Giglietto, N.; /UC, Santa Cruz /INFN, Pisa /Pisa U. /INFN, Trieste /INFN, Rome /Rome U.,Tor Vergata /SLAC /INFN, Bari /Bari U. /INFN, Perugia /Perugia U. /Udine U. /Hiroshima U. /NASA, Goddard /Maryland U. /Tokyo Inst. Tech. /INFN, Padua /Padua U. /Pisa, Scuola Normale Superiore

    2007-04-16

    The Tracker subsystem of the Large Area Telescope (LAT) science instrument of the Gamma-ray Large Area Space Telescope (GLAST) mission has been completed and tested. It is the central detector subsystem of the LAT and serves both to convert an incident gamma-ray into an electron-positron pair and to track the pair in order to measure the gamma-ray direction. It also provides the principal trigger for the LAT. The Tracker uses silicon strip detectors, read out by custom electronics, to detect charged particles. The detectors and electronics are packaged, along with tungsten converter foils, in 16 modular, high-precision carbon-composite structures. It is the largest silicon-strip detector system ever built for launch into space, and its aggressive design emphasizes very low power consumption, passive cooling, low noise, high efficiency, minimal dead area, and a structure that is highly transparent to charged particles. The test program has demonstrated that the system meets or surpasses all of its performance specifications as well as environmental requirements. It is now installed in the completed LAT, which is being prepared for launch in early 2008.

  5. Rationally designed mutations convert de novo amyloid-like fibrils into monomeric beta-sheet proteins.

    PubMed

    Wang, Weixun; Hecht, Michael H

    2002-03-05

    Amyloid fibrils are associated with a variety of neurodegenerative maladies including Alzheimer's disease and the prion diseases. The structures of amyloid fibrils are composed of beta-strands oriented orthogonal to the fibril axis ("cross beta" structure). We previously reported the design and characterization of a combinatorial library of de novo beta-sheet proteins that self-assemble into fibrillar structures resembling amyloid. The libraries were designed by using a "binary code" strategy, in which the locations of polar and nonpolar residues are specified explicitly, but the identities of these residues are not specified and are varied combinatorially. The initial libraries were designed to encode proteins containing amphiphilic beta-strands separated by reverse turns. Each beta-strand was designed to be seven residues long, with polar (open circle) and nonpolar (shaded circle) amino acids arranged with an alternating periodicity ([see text]). The initial design specified the identical polar/nonpolar pattern for all of the beta-strands; no strand was explicitly designated to form the edges of the resulting beta-sheets. With all beta-strands preferring to occupy interior (as opposed to edge) locations, intermolecular oligomerization was favored, and the proteins assembled into amyloid-like fibrils. To assess whether explicit design of edge-favoring strands might tip the balance in favor of monomeric beta-sheet proteins, we have now redesigned the first and/or last beta-strands of several sequences from the original library. In the redesigned beta-strands, the binary pattern is changed from [see text] (K denotes lysine). The presence of a lysine on the nonpolar face of a beta-strand should disfavor fibrillar structures because such structures would bury an uncompensated charge. The nonpolar right arrow lysine mutations, therefore, would be expected to favor monomeric structures in which the [see text] sequences form edge strands with the charged lysine side

  6. Design of a 2.5 Gbps Optical Transmitter for the International Space Station

    NASA Technical Reports Server (NTRS)

    Ortiz, Gerardo G.; Jeganathan, Muthu; Sandusky, John V.; Hemmati, Hamid

    1999-01-01

    A high data rate laser transmitter assembly (LTA) has been designed as the source for an optical free-space communication link between the International Space Station and the 1-meter Optical Communication Telescope Laboratory (OCTL) to be built at the Table Mountain Facility (IMF, Wrightwood, CA). The transmitter design concept uses a fiber-based master oscillator power amplifier (MOPA) configuration with an average output power of 200 made at a 1550 nm transmit wavelength. This transmitter source is also designed to provide a signal at 980 nm to the Silicon-based focal plane array for the point-ahead beam control function. This novel integration of a 980 nm boresight signal allows the use of Silicon based imagers for the acquisition/tracking and point-ahead functions, yet permits the transmit signal to be at any wavelength outside the Silicon sensitivity. The LTA, a sub-system of the Flight Terminal, has been designed to have a selectable data rate from 155 - 2500 Mbps in discrete steps. It also incorporates a 2.5 Gbps pseudo-random bit sequence (PRBS) generator for complete link testing and diagnostics. The design emphasizes using commercial off the shelf components (COTS).

  7. ECLSS Design for the International Space Station Nodes 2 and 3

    NASA Technical Reports Server (NTRS)

    Carrasquillo, Robyn L.; Bertotto, Dario

    1999-01-01

    The International Space Station (ISS) modules Nodes 2 and 3 are currently under development by Alenia Spazio and the Marshall Space Flight Center (MSFC). The design of the Environmental Control and Life Support Systems (ECLSS) for these two modules have some similarities but many differences. The Node 2 ECLSS provides inter- and intramodule ventilation, temperature and humidity control, fire detection and suppression, and distribution of atmosphere samples, low pressure and recharge oxygen and nitrogen, fuel cell water and wastewater. Design Review 1 was held in March 1998. Fabrication of the ducting, tubing, and support structure is ongoing with Design Review 2 planned for December 1999. In addition to providing the same functions as Node 2, the ECLSS for Node 3 includes carbon dioxide removal, trace contaminant control, atmosphere monitoring, atmosphere pressure control, oxygen generation, urine and potable water processing, waste management, and potable water distribution to support the habitability functions relocated from the U.S. Hab module. Scarring for future incorporation of carbon dioxide reduction is also included. Design Review 1 is planned for July 1999. An overview of each Node's system design as well as issues and challenges are discussed.

  8. Space Station Furnace Facility. Volume 1: Requirements definition and conceptual design study, executive summary

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The Space Station Freedom Furnace (SSFF) Study was awarded on June 2, 1989, to Teledyne Brown Engineering (TBE) to define an advanced facility for materials research in the microgravity environment of Space Station Freedom (SSF). The SSFF will be designed for research in the solidification of metals and alloys, the crystal growth of electronic and electro-optical materials, and research in glasses and ceramics. The SSFF is one of the first 'facility' class payloads planned by the Microgravity Science and Applications Division (MSAD) of the Office of Space Science and Applications of NASA Headquarters. This facility is planned for early deployment during man-tended operations of the SSF with continuing operations through the Permanently Manned Configuration (PMC). The SSFF will be built around a general 'Core' facility which provides common support functions not provided by SSF, common subsystems which are best centralized, and common subsystems which are best distributed with each experiment module. The intent of the facility approach is to reduce the overall cost associated with implementing and operating a variety of experiments. This is achieved by reducing the launch mass and simplifying the hardware development and qualification processes associated with each experiment. The Core will remain on orbit and will require only periodic maintenance and upgrading while new Furnace Modules, samples, and consumables are developed, qualified, and transported to the SSF. The SSFF Study was divided into two phases: phase 1, a definition study phase, and phase 2, a design and development phase. The definition phase 1 is addressed. Phase 1 was divided into two parts. In the first part, the basic part of the effort, covered the preliminary definition and assessment of requirements; conceptual design of the SSFF; fabrication of mockups; and the preparation for and support of the Conceptual Design Review (CoDR). The second part, the option part, covered requirements update and

  9. Design possibilities and peformance of combined cycle operation of converted steam power plants

    SciTech Connect

    Linnemeijer, M.J.J.; Van Buijtenen, J.P. )

    1988-01-01

    An interesting method for boosting thermal efficiency and/or power output of an existing steam power plant is repowering through the addition of gas turbines. The forced draught fan is replaced by a gas turbine and the air heater by low-temperature economisers. This conversion will change the performance of the installation significantly. Therefore the design of the existing installation has to be reviewed based on new unit performance calculations. Since the conversion has to be economical, it is important to find a good compromise between investment and improvement of performance. This paper describes the change in performance of the installation created by the conversion in general and a number of design possibilities based on the experience gained with the realization of a number of conversion projects.

  10. Methodology of design and analysis of external walls of space station for hypervelocity impacts by meteoroids and space debris

    NASA Technical Reports Server (NTRS)

    Batla, F. A.

    1986-01-01

    The development of criteria and methodology for the design and analysis of Space Station wall elements for collisions with meteoroids and space debris at hypervelocities is discussed. These collisions will occur at velocities of 10 km/s or more and can be damaging to the external wall elements of the Space Station. The wall elements need to be designed to protect the pressurized modules of the Space Station from functional or structural failure due to these collisions at hypervelocities for a given environment and population of meteoroids and space debris. The design and analysis approach and the associated computer program presented is to achieve this objective, including the optimization of the design for a required overall probability of no penetration. The approach is based on the presently available experimental and actual data on meteoroids and space debris flux and damage assessments and the empirical relationships resulting from the hypervelocity impact studies in laboratories.

  11. Potential impact of new power system technology on the design of a manned space station

    SciTech Connect

    Fordyce, J.S.; Schwartz, H.J.

    1984-01-01

    Large, more complex spacecraft of the future such as a manned Space Station will require electric power systems of 100 kW and more, orders of magnitude greater than the present state of the art. Power systems at this level will have a significant impact on the spacecraft design. Historically, long-lived spacecraft have relied on silicon solar cell arrays, a nickel-cadium storage battery and operation at 28 V dc. These technologies lead to large array areas and heavy batteries for a Space Station application. This, in turn, presents orbit altitude maintenance, attitude control, energy management and launch weight and volume constraints. Size (area) and weight of such a power system can be reduced if new higher efficiency conversion and lighter weight storage technologies are used. Several promising technology options including concentrator solar photovoltaic arrays, solar thermal dynamic and ultimately nuclear dynamic systems to reduce area are discussed. Also higher energy storage systems such as nickel-hydrogen and the regenerative fuel cell (RFC) and higher voltage power distribution which add system flexibility, simplicity and reduce weight are examined. Emphasis is placed on the attributes and development status of emerging technologies that are sufficiently developed that they could be available for flight use in the early to mid 1990's.

  12. Design and Development of a CPCI-Based Electronics Package for Space Station Experiments

    NASA Technical Reports Server (NTRS)

    Kolacz, John S.; Clapper, Randy S.; Wade, Raymond P.

    2006-01-01

    The NASA John H. Glenn Research Center is developing a Compact-PCI (CPCI) based electronics package for controlling space experiment hardware on the International Space Station. Goals of this effort include an easily modified, modular design that allows for changes in experiment requirements. Unique aspects of the experiment package include a flexible circuit used for internal interconnections and a separate enclosure (box in a box) for controlling 1 kW of power for experiment fuel heating requirements. This electronics package was developed as part of the FEANICS (Flow Enclosure Accommodating Novel Investigations in Combustion of Solids) mini-facility which is part of the Fluids and Combustion Facility s Combustion Integrated Rack (CIR). The CIR will be the platform for future microgravity combustion experiments and will reside on the Destiny Module of the International Space Station (ISS). The FEANICS mini-facility will be the primary means for conducting solid fuel combustion experiments in the CIR on ISS. The main focus of many of these solid combustion experiments will be to conduct applied scientific investigations in fire-safety to support NASA s future space missions. A description of the electronics package and the results of functional testing are the subjects of this report. The report concludes that the use of innovative packaging methods combined with readily available COTS hardware can provide a modular electronics package which is easily modified for changing experiment requirements.

  13. The potential impact of new power system technology on the design of a manned Space Station

    NASA Technical Reports Server (NTRS)

    Fordyce, J. S.; Schwartz, H. J.

    1984-01-01

    Larger, more complex spacecraft of the future such as a manned Space Station will require electric power systems of 100 kW and more, orders of magnitude greater than the present state of the art. Power systems at this level will have a significant impact on the spacecraft design. Historically, long-lived spacecraft have relied on silicon solar cell arrays, a nickel-cadmium storage battery and operation at 28 V dc. These technologies lead to large array areas and heavy batteries for a Space Station application. This, in turn, presents orbit altitude maintenance, attitude control, energy management and launch weight and volume constraints. Size (area) and weight of such a power system can be reduced if new higher efficiency conversion and lighter weight storage technologies are used. Several promising technology options including concentrator solar photovoltaic arrays, solar thermal dynamic and ultimately nuclear dynamic systems to reduce area are discussed. Also, higher energy storage systems such as nickel-hydrogen and the regenerative fuel cell (RFC) and higher voltage power distribution which add system flexibility, simplicity and reduce weight are examined. Emphasis placed on the attributes and development status of emerging technologies that are sufficiently developed so that they could be available for flight use in the early to mid 1990's.

  14. The potential impact of new power system technology on the design of a manned space station

    NASA Technical Reports Server (NTRS)

    Fordyce, J. S.; Schwartz, H. J.

    1984-01-01

    Larger, more complex spacecraft of the future such as a manned Space Station will require electric power systems of 100 kW and more, orders of magnitude greater than the present state of the art. Power systems at this level will have a significant impact on the spacecraft design. Historically, long-lived spacecraft have relied on silicon solar cell arrays, a nickel-cadmium storage battery and operation at 28 V dc. These technologies lead to large array areas and heavy batteries for a Space Station application. This, in turn, presents orbit altitude maintenance, attitude control, energy management and launch weight and volume constraints. Size (area) and weight of such a power system can be reduced if new higher efficiency conversion and lighter weight storage technologies are used. Several promising technology options including concentrator solar photovoltaic arrays, solar thermal dynamic and ultimately nuclear dynamic systems to reduce area are discussed. Also, higher energy storage systems such as nickel-hydrogen and the regenerative fuel cell (RFC) and higher voltage power distribution which add system flexibility, simplicity and reduce weight are examined. Emphasis is placed on the attributes and development status of emerging technologies that are sufficiently developed so that they could be available for flight use in the early to mid 1990's.

  15. Research on design feasibility of high-power light-weight dc-to-dc converters for space power applications

    NASA Technical Reports Server (NTRS)

    Wilson, T. G.

    1981-01-01

    Utilizing knowledge gained from past experience with experimental current-or-voltage step-up dc-to-dc converter power stages operating at output powers up to and in excess of 2 kW, a new experimental current-or-voltage step-up power stage using paralleled bipolar junction transistors (BJTs) as the controlled power switch, was constructed during the current reporting period. The major motivation behind the construction of this new experimental power stage was to improve the circuit layout so as to reduce the effects of stray circuit parasitic inductances resulting from excess circuit lead lengths and circuit loops, and to take advantage of the layout improvements which could be made when some recently-available power components, particularly power diodes and polypropylene filter capacitors, were incorporated into the design.

  16. Research on design feasibility of high-power light-weight dc-to-dc converters for space power applications

    NASA Astrophysics Data System (ADS)

    Wilson, T. G.

    1981-11-01

    Utilizing knowledge gained from past experience with experimental current-or-voltage step-up dc-to-dc converter power stages operating at output powers up to and in excess of 2 kW, a new experimental current-or-voltage step-up power stage using paralleled bipolar junction transistors (BJTs) as the controlled power switch, was constructed during the current reporting period. The major motivation behind the construction of this new experimental power stage was to improve the circuit layout so as to reduce the effects of stray circuit parasitic inductances resulting from excess circuit lead lengths and circuit loops, and to take advantage of the layout improvements which could be made when some recently-available power components, particularly power diodes and polypropylene filter capacitors, were incorporated into the design.

  17. DESIGNING AN OPPORTUNITY FUEL WITH BIOMASS AND TIRE-DERIVED FUEL FOR COFIRING AT WILLOW ISLAND GENERATING STATION AND COFIRING SAWDUST WITH COAL AT ALBRIGHT GENERATING STATION

    SciTech Connect

    K. Payette; D. Tillman

    2003-01-01

    During the period October 1, 2002--December 31, 2002, Allegheny Energy Supply Co., LLC (Allegheny) completed the first year of testing at the Willow Island cofiring project. This included data acquisition and analysis associated with certain operating parameters and environmental results. Over 2000 hours of cofiring operation were logged at Willow Island, and about 4,000 tons of sawdust were burned along with slightly more tire-derived fuel (TDF). The results were generally favorable. During this period, also, a new grinder was ordered for the Albright Generating Station to handle oversized material rejected by the disc screen. This report summarizes the activities associated with the Designer Opportunity Fuel program, and demonstrations at Willow Island and Albright Generating Stations. It details the test results at Willow Island and summarizes the grinder program at Albright.

  18. Tracy Power Station -- Unit No. 4, Pinon Pine Power Project Public Design Report

    SciTech Connect

    1994-12-01

    This Public Design Report describes the Pinon Pine Project which will be located at the Sierra Pacific Power Company`s (SPPCO) Tracy Station near Reno, Nevada. The integrated gasification combined-cycle (IGCC) plant is designed to process 880 tones per day (TPD) of bituminous coal producing approximately 107 gross megawatts of electric power (MWe). This project is receiving cost-sharing from the US Department of Energy (DOE) in accordance with DOE Cooperative Agreement DE-FC2192MC29309. The plant incorporates the Kellogg-Rust-Westinghouse (KRW) fluidized bed gasification technology which produces a low-Btu gas which is used as fuel in a combined cycle power plant which has been modified to accommodate the fuel gas produced by an air-blown gasifier. The gasification system also includes hot gas removal of particulates and sulfur compounds from the fuel gas resulting in a plant with exceptionally low atmospheric emissions. Desulfurization is accomplished by a combination of limestone injection into the KRW fluidized bed gasifier and by a transport reactor system. Particulate removal is accomplished by high efficiency cyclones and a barrier filter. The Pinon Pine Project Schedule is divided into three phases. Phase I includes permitting and preliminary design. Phase II, which overlaps Phase I, covers detailed design, procurement, and construction. Phase III will cover the initial operation and demonstration portion of the project.

  19. Addressing Challenges to the Design & Test of Operational Lighting Environments for the International Space Station

    NASA Technical Reports Server (NTRS)

    Clark, Toni A.

    2014-01-01

    In our day to day lives, the availability of light, with which to see our environment, is often taken for granted. The designers of land based lighting systems use sunlight and artificial light as their toolset. The availability of power, quantity of light sources, and variety of design options are often unlimited. The accessibility of most land based lighting systems makes it easy for the architect and engineer to verify and validate their design ideas. Failures with an implementation, while sometimes costly, can easily be addressed by renovation. Consider now, an architectural facility orbiting in space, 260 miles above the surface of the earth. This human rated architectural facility, the International Space Station (ISS) must maintain operations every day, including life support and appropriate human comforts without fail. The facility must also handle logistics of regular shipments of cargo, including new passengers. The ISS requires accommodations necessary for human control of machine systems. Additionally, the ISS is a research facility and supports investigations performed inside and outside its livable volume. Finally, the facility must support remote operations and observations by ground controllers. All of these architectural needs require a functional, safe, and even an aesthetic lighting environment. At Johnson Space Center, our Habitability and Human Factors team assists our diverse customers with their lighting environment challenges, via physical test and computer based analysis. Because of the complexity of ISS operational environment, our team has learned and developed processes that help ISS operate safely. Because of the dynamic exterior lighting environment, uses computational modeling to predict the lighting environment. The ISS' orbit exposes it to a sunrise every 90 minutes, causing work surfaces to quickly change from direct sunlight to earthshine to total darkness. Proper planning of vehicle approaches, robotics operations, and crewed

  20. The Design and Application of Data Storage System in Miyun Satellite Ground Station

    NASA Astrophysics Data System (ADS)

    Xue, Xiping; Su, Yan; Zhang, Hongbo; Liu, Bin; Yao, Meijuan; Zhao, Shu

    2015-04-01

    China has launched Chang'E-3 satellite in 2013, firstly achieved soft landing on moon for China's lunar probe. Miyun satellite ground station firstly used SAN storage network system based-on Stornext sharing software in Chang'E-3 mission. System performance fully meets the application requirements of Miyun ground station data storage.The Stornext file system is a sharing file system with high performance, supports multiple servers to access the file system using different operating system at the same time, and supports access to data on a variety of topologies, such as SAN and LAN. Stornext focused on data protection and big data management. It is announced that Quantum province has sold more than 70,000 licenses of Stornext file system worldwide, and its customer base is growing, which marks its leading position in the big data management.The responsibilities of Miyun satellite ground station are the reception of Chang'E-3 satellite downlink data and management of local data storage. The station mainly completes exploration mission management, receiving and management of observation data, and provides a comprehensive, centralized monitoring and control functions on data receiving equipment. The ground station applied SAN storage network system based on Stornext shared software for receiving and managing data reliable.The computer system in Miyun ground station is composed by business running servers, application workstations and other storage equipments. So storage systems need a shared file system which supports heterogeneous multi-operating system. In practical applications, 10 nodes simultaneously write data to the file system through 16 channels, and the maximum data transfer rate of each channel is up to 15MB/s. Thus the network throughput of file system is not less than 240MB/s. At the same time, the maximum capacity of each data file is up to 810GB. The storage system planned requires that 10 nodes simultaneously write data to the file system through 16

  1. Validation of a station-prototype designed to integrate temporally soil N2O fluxes: IPNOA Station prototype.

    NASA Astrophysics Data System (ADS)

    Laville, Patricia; Volpi, Iride; Bosco, Simona; Virgili, Giorgio; Neri, Simone; Continanza, Davide; Bonari, Enrico

    2016-04-01

    Nitrous oxide (N2O) flux measurements from agricultural soil surface still accounts for the scientific community as major challenge. The evaluations of integrated soil N2O fluxes are difficult because these emissions are lower than for the other greenhouse gases sources (CO2, CH4). They are also sporadic, because highly dependent on few environmental conditions acting as limiting factors. Within a LIFE project (IPNOA: LIFE11 ENV/IT/00032) a station prototype was developed to integrate annually N2O and CO2 emissions using automatically chamber technique. Main challenge was to develop a device enough durable to be able of measuring in continuous way CO2 and N2O fluxes with sufficient sensitivity to allow make reliable assessments of soil GHG measurements with minimal technical field interventions. The IPNOA station prototype was developed by West System SRL and was set up during 2 years (2014 -2015) in an experimental maize field in Tuscan. The prototype involved six automatic chambers; the complete measurement cycle was of 2 hours. Each chamber was closing during 20 min and biogas accumulations were monitoring in line with IR spectrometers. Auxiliary's measurements including soil temperatures and water contents as weather data were also monitoring. All data were managed remotely with the same acquisition software installed in the prototype control unit. The operation of the prototype during the two cropping years allowed testing its major features: its ability to evaluate the temporal variation of N2O soil fluxes during a long period with weather conditions and agricultural managements and to prove the interest to have continuous measurements of fluxes. The temporal distribution of N2O fluxes indicated that emissions can be very large and discontinuous over short periods less ten days and that during about 70% of the time N2O fluxes were around detection limit of the instrumentation, evaluated to 2 ng N ha-1 day-1. N2O emission factor assessments were 1.9% in 2014

  2. Intelligent Virtual Station (IVS)

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The Intelligent Virtual Station (IVS) is enabling the integration of design, training, and operations capabilities into an intelligent virtual station for the International Space Station (ISS). A viewgraph of the IVS Remote Server is presented.

  3. Liquid metal thermal electric converter

    DOEpatents

    Abbin, Joseph P.; Andraka, Charles E.; Lukens, Laurance L.; Moreno, James B.

    1989-01-01

    A liquid metal thermal electric converter which converts heat energy to electrical energy. The design of the liquid metal thermal electric converter incorporates a unique configuration which directs the metal fluid pressure to the outside of the tube which results in the structural loads in the tube to be compressive. A liquid metal thermal electric converter refluxing boiler with series connection of tubes and a multiple cell liquid metal thermal electric converter are also provided.

  4. International Space Station USOS Crew Quarters On-orbit vs Design Performance Comparison

    NASA Technical Reports Server (NTRS)

    Broyan, James Lee, Jr.; Borrego, Melissa Ann; Bahr, Juergen F.

    2008-01-01

    The International Space Station (ISS) United States Operational Segment (USOS) received the first two permanent ISS Crew Quarters (CQ) on Utility Logistics Flight Two (ULF2) in November 2008. Up to four CQs can be installed into the Node 2 element to increase the ISS crewmember size to six. The CQs provide private crewmember space with enhanced acoustic noise mitigation, integrated radiation reduction material, communication equipment, redundant electrical systems, and redundant caution and warning systems. The racksized CQ is a system with multiple crewmember restraints, adjustable lighting, controllable ventilation, and interfaces that allow each crewmember to personalize their CQ workspace. The deployment and initial operational checkout during integration of the ISS CQ to the Node is described. Additionally, the comparison of on-orbit to original design performance is outlined for the following key operational parameters: interior acoustic performance, air flow rate, temperature rise, and crewmember feedback on provisioning and restraint layout.

  5. Conceptual design and programmatics studies of space station accommodations for Life Sciences Research Facilities (LSRF)

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Conceptual designs and programmatics of the space station accommodations for the Life Sciences Research Facilities (LSRF) are presented. The animal ECLSS system for the LSRF provides temperature-humidity control, air circulation, and life support functions for experimental subjects. Three ECLSS were studied. All configurations presented satisfy the science requirements for: animal holding facilities with bioisolation; facilities interchangeable to hold rodents, small primates, and plants; metabolic cages interchangeable with standard holding cages; holding facilities adaptable to restrained large primates and rodent breeding/nesting cages; volume for the specified instruments; enclosed ferm-free workbench for manipulation of animals and chemical procedures; freezers for specimen storage until return; and centrifuge to maintain animals and plants at fractional g to 1 g or more, with potential for accommodating humans for short time intervals.

  6. Evaluation of Pactruss design characteristics critical to space station primary structure

    NASA Technical Reports Server (NTRS)

    Hedgepeth, John M.

    1987-01-01

    Several aspects of the possible application of the Pactruss concept to the primary truss structure of the space station are investigated. Estimates are made of the loads and hinge moments in deploying diagonal members as full deployment is approached. Included are the effects of beam columning and compliance of the surrounding structure. Requirements for joint design are suggested and a two-stage mid-diagonal latching hinge concept is described or analyzed. The problems with providing the experimental and theoretical tools needed for assuring reliable synchronous deployment are discussed and a first attempt at high-fidelity analytical simulation with NASTRAN is described. An alternative construction scenario in which the entire dual-keel truss structure is deployed as a single Shuttle payload is suggested.

  7. Preliminary control system design and analysis for the Space Station Furnace Facility thermal control system

    NASA Technical Reports Server (NTRS)

    Jackson, M. E.

    1995-01-01

    This report presents the Space Station Furnace Facility (SSFF) thermal control system (TCS) preliminary control system design and analysis. The SSFF provides the necessary core systems to operate various materials processing furnaces. The TCS is defined as one of the core systems, and its function is to collect excess heat from furnaces and to provide precise cold temperature control of components and of certain furnace zones. Physical interconnection of parallel thermal control subsystems through a common pump implies the description of the TCS by coupled nonlinear differential equations in pressure and flow. This report formulates the system equations and develops the controllers that cause the interconnected subsystems to satisfy flow rate tracking requirements. Extensive digital simulation results are presented to show the flow rate tracking performance.

  8. Payload specialist station study. Volume 2, part 1: Preliminary design document

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The details of six tasks of the payload Specialist Station study are discussed: (1) derive payload control and display requirements; (2) perform functional analyses; (3) perform system synthesis; (4) perform trade studies; (5) perform preliminary design; and (6) provide data format. Functional analysis diagrams were developed for the study payloads. These diagrams presented the payload's functional activities flow based on the six mission phases established. These phases are: (1) launch, ascent, orbit insertion; (2) on-orbit checkout and activation; (3) on-orbit operation; (4) deployment/retrieval; (5) on-orbit deactivation; and (6) descent, landing, post-landing. To perform system synthesis the widest variety of available hardware and software, as individual pieces of equipment and as systems, was investigated. The intent was to synthesize a complete AFD system or systems which could accommodate the range of requirements identified for the study missions.

  9. Design and evaluation of FDDI fiber optics networkfor Ethernets, VAX's and Ingraph work stations

    NASA Technical Reports Server (NTRS)

    Wernicki, M. Chris

    1992-01-01

    The purpose of this project is to design and evaluate the FDDI Fiber Optics Network for Ethernets, VAX's, and Ingraph work stations. From the KSC Headquarters communication requirement, it would be necessary to develop the FDDI network based on IEEE Standards outlined in the ANSI X3T9.5, Standard 802.3 and 802.5 topology - direct link via intermediate concentrator and bridge/router access. This analysis should examine the major factors that influence the operating conditions of the Headquarters Fiber plant. These factors would include, but are not limited to the interconnecting devices such as repeaters, bridges, routers and many other relevant or significant FDDI characteristics. This analysis is needed to gain a better understanding of overall FDDI performance.

  10. Implications of privacy needs and interpersonal distancing mechanisms for space station design

    NASA Technical Reports Server (NTRS)

    Harrison, A. A.; Sommer, R.; Struthers, N.; Hoyt, K.

    1985-01-01

    Privacy needs, or the need of people to regulate their degree of contact with one another, and interpersonal distancing mechanisms, which serve to satisfy these needs, are common in all cultures. Isolation, confinement, and other conditions accociated with space flight may at once accentuate privacy needs and limit the availability of certain common interpersonal contact. Loneliness occurs when people have less contact with one another than they desire. Crowding occurs when people have more contact with one another than they desire. Crowding, which is considered the greater threat to members of isolated and confined groups, can contribute to stress, a low quality of life, and poor performance. Drawing on the general literature on privacy, personal space, and interpersonal distancing, and on specialized literature on life aboard spacecraft and in spacecraft-analogous environments, a quantitative model for understanding privacy, interpersonal distancing, loneliness, and crowding was developed and the practical implications of this model for space station design were traced.

  11. Workshop on Instructional Features and Instructor/Operator Station Design for Training Systems.

    ERIC Educational Resources Information Center

    Ricard, G. L., Ed.; And Others

    These 19 papers review current research and development work related to the operation of the instructor's station of training systems, with emphasis on developing functional station specifications applicable to a variety of simulation-based training situations. Topics include (1) instructional features; (2) instructor/operator station research and…

  12. Japan's participation in space station design: Feasibility study of GaAs solar cells for space station applications

    NASA Technical Reports Server (NTRS)

    1986-01-01

    The report gives the results of feasibility studies and a cost analysis done on GaAs solar battery cells for space stations. The studies and their results are as follows: (1) Cell size - The 2 x 4 cm cell size was found superior to the 4 x 4 cm cell; (2) Manufacturing technology - Overall, LPE crystal growth was found more suitable than MO-CVD. Current technology for post-growth processes and applying large-area cover glass can be used with few or no modifications; (3) Cell assemblies - Tests for mechanical and thermal stresses encountered from assembly through operation are recommended; (4) Procuring materials - Steps should be taken to avoid sharp price increases due to a speculative gallium market. There are no problems with arsenic materials; (5) Production facilities - The capital investment needed remains to be determined, but a working area of 4000 m2 will be required; (6) Cell costs to be determined; (7) Cell development-supply plan - Two-year lead time will be needed to develop the necessary technology and prepare for production.

  13. Optimal design and operation of booster chlorination stations layout in water distribution systems.

    PubMed

    Ohar, Ziv; Ostfeld, Avi

    2014-07-01

    This study describes a new methodology for the disinfection booster design, placement, and operation problem in water distribution systems. Disinfectant residuals, which are in most cases chlorine residuals, are assumed to be sufficient to prevent growth of pathogenic bacteria, yet low enough to avoid taste and odor problems. Commonly, large quantities of disinfectants are released at the sources outlets for preserving minimum residual disinfectant concentrations throughout the network. Such an approach can cause taste and odor problems near the disinfectant injection locations, but more important hazardous excessive disinfectant by-product formations (DBPs) at the far network ends, of which some may be carcinogenic. To cope with these deficiencies booster chlorination stations were suggested to be placed at the distribution system itself and not just at the sources, motivating considerable research in recent years on placement, design, and operation of booster chlorination stations in water distribution systems. The model formulated and solved herein is aimed at setting the required chlorination dose of the boosters for delivering water at acceptable residual chlorine and TTHM concentrations for minimizing the overall cost of booster placement, construction, and operation under extended period hydraulic simulation conditions through utilizing a multi-species approach. The developed methodology links a genetic algorithm with EPANET-MSX, and is demonstrated through base runs and sensitivity analyses on a network example application. Two approaches are suggested for dealing with water quality initial conditions and species periodicity: (1) repetitive cyclical simulation (RCS), and (2) cyclical constrained species (CCS). RCS was found to be more robust but with longer computational time.

  14. Design of a 40/50 GHz satellite ground station for fade mitigation experiments

    NASA Astrophysics Data System (ADS)

    Koudelka, O.; Schmidt, M.; Ebert, J.

    2013-05-01

    Due to the increasing demand in satellite capacity, driven by applications such as high-definition television (HDTV), 3D-TV and interactive broadband services, higher frequency bands will have to be exploited. The capacity on Ku-band is already becoming scarce and Ka-band systems are more commonly used. It can be expected that 40 and 50 GHz (Q and V band) will have to be used in the future. At these frequencies the wave propagation effects have a significant impact on the performance. The traditional approach of implementing large fade margins in the system design is not suitable as it leads to expensive ground terminals. Fade mitigation by adaptive coding and modulation (ACM) is a cost-efficient method. To investigate the Q/V-band for future commercial exploitation, ESA's ALPHASAT satellite will provide experimental payloads for communications and wave propagation experiments. In Graz a Q/V-band ground station is currently under development. It will be equipped with a 3 m tracking antenna, a 50 W Klystron amplifier and a 290 K LNA. Fade mitigation experiments will be conducted, initially using DVB-S2 modems which allow to vary the modulation scheme, the Forward Error Correction code and the symbol rate under control of the ACM computer. In addition, uplink power control can be combined with the ACM methods. A specially developed signal analyser provides precise measurement of the signal/noise ratio. In addition, propagation data will be available from a beacon receiver, also developed by Joanneum Research. Important goals of the experiment are to investigate the reliability of links under realistic operating conditions using ACM and to develop efficient ACM and signal/noise ratio measurement algorithms which can be later implemented in optimised modems for Q/V-band. The paper describes the ground station design and addresses the planned fade mitigation experiments.

  15. Design considerations for a 1 MW CW gyrotron with an internal converter

    SciTech Connect

    Felch, K.; Chu, T.S.; Huey, H.; Jory, H.; Neilson, J.; Schumacher, R.; Lorbeck, J.A.; Vernon, R.J.

    1993-07-01

    Varian is carrying out the development of high-power, CW gyrotrons at frequencies ranging from 100--140 GHz. Recent experiments, carried out at a frequency of 110 GHz, resulted in the generation of output powers of 500 kW for 2.5-second pulses and 1 MW for 1 ms pulse durations. The output mode of this tube was a whispering-gallery mode, based on the TE{sub 22,2} mode employed in the interaction cavity. Current design activity is aimed at producing a 1 MW CW gryotron at the same frequency, but with a guassian output mode structure. This type of output mode is desirable for low-loss transmission in a corrugated waveguide or mirror transmission line. In addition to the change in output coupling, the cavity mode will be changed to the TE{sub 22,6} mode. The higher order cavity mode is consistent with higher power or higher frequency requirements that will be addressed in subsequent development activities.

  16. A single aromatic core mutation converts a designed "primitive" protein from halophile to mesophile folding.

    PubMed

    Longo, Liam M; Tenorio, Connie A; Kumru, Ozan S; Middaugh, C Russell; Blaber, Michael

    2015-01-01

    The halophile environment has a number of compelling aspects with regard to the origin of structured polypeptides (i.e., proteogenesis) and, instead of a curious niche that living systems adapted into, the halophile environment is emerging as a candidate "cradle" for proteogenesis. In this viewpoint, a subsequent halophile-to-mesophile transition was a key step in early evolution. Several lines of evidence indicate that aromatic amino acids were a late addition to the codon table and not part of the original "prebiotic" set comprising the earliest polypeptides. We test the hypothesis that the availability of aromatic amino acids could facilitate a halophile-to-mesophile transition by hydrophobic core-packing enhancement. The effects of aromatic amino acid substitutions were evaluated in the core of a "primitive" designed protein enriched for the 10 prebiotic amino acids (A,D,E,G,I,L,P,S,T,V)-having an exclusively prebiotic core and requiring halophilic conditions for folding. The results indicate that a single aromatic amino acid substitution is capable of eliminating the requirement of halophile conditions for folding of a "primitive" polypeptide. Thus, the availability of aromatic amino acids could have facilitated a critical halophile-to-mesophile protein folding adaptation-identifying a selective advantage for the incorporation of aromatic amino acids into the codon table.

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

    PubMed

    Mattila, Hannu-Petteri; Zevenhoven, Ron

    2014-03-01

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

  18. The Gas-Grain Simulation Facility (GGSF) for Space Station Freedom - Design concept

    NASA Technical Reports Server (NTRS)

    Gat, N.; Kropp, J. L.; Huntington, J. L.; Fonda, M. L.

    1992-01-01

    The GGSF is specifically designed to accommodate micro-g experiments that investigate long-term effects and interactions between submicron to centimeter size particles. The paper introduces the science disciplines and the type of experiments that are currently envisioned for the GGSF. The broad range of science and technology requirements are discussed, and the Space Station Freedom (SSF) accommodations, and available utilities are reviewed. Based on the requirements and the available accommodations, a facility conceptual design is outlined. The required subsystems are listed, and the rationale and considerations that lead to the selected approach, delineated. The present GGSF concept is that of a modular facility system comprising a flight rack and an array of fully compatible and interchangeable subsystems that are designed to meet a diverse set of science requirements. The modularity allows for future upgrade of various subsystems as technology evolves and for introduction of new modules to accommodate new or different experiments. These features are essential for a facility that is expected to be in service on board the SSF for 10 years or more.

  19. Design and Verification of Space Station EVA-Operated Truss Attachment System

    NASA Technical Reports Server (NTRS)

    Katell, Gabriel

    2001-01-01

    This paper describes the design and verification of a system used to attach two segments of the International Space Station (ISS). This system was first used in space to mate the P6 and Z1 trusses together in December 2000, through a combination of robotic and extravehicular tasks. Features that provided capture, coarse alignment, and fine alignment during the berthing process are described. Attachment of this high value hardware was critical to the ISS's sequential assembly, necessitating the inclusion of backup design and operational features. Astronauts checked for the proper performance of the alignment and bolting features during on-orbit operations. During berthing, the system accommodates truss-to-truss relative displacements that are caused by manufacturing tolerances and on-orbit thermal gradients. After bolt installation, the truss interface becomes statically determinate with respect to in-plane shear loads and isolates attach bolts from bending moments. The approach used to estimate relative displacements and the means of accommodating them is explained. Confidence in system performance was achieved through a cost-effective collection of tests and analyses, including thermal, structural, vibration, misalignment, contact dynamics, underwater simulation, and full-scale functional testing. Design considerations that have potential application to other mechanisms include accommodating variations of friction coefficients in the on-orbit joints, wrench torque tolerances, joint preload, moving element clearances at temperature extremes, and bolt-nut torque reaction.

  20. Design for an integrated discipline operations control center for Space Station Freedom

    NASA Technical Reports Server (NTRS)

    Haines, Richard F.

    1993-01-01

    This paper presents selected features of a human factors oriented plan for a Space Station Freedom (SSF) ground Discipline Operations Center (DOC) that is integrated with other work areas used by multidisciplinary life scientists. This combined facility is referred to as an integrated DOC or IDOC. This plan is based upon the assumption that there will be a constantly changing array of specialized equipment and procedures used by life sciences principal investigators (PI) on the ground which must be linked to SSF through various DOC systems. Other sites will also be able to communicate with SSF (Anon., 1992). It is also assumed that cost reduction will be a major design consideration and that one integrated structure will be less expensive to build and operate than two separate ones. Since both the DOC personnel and PIs will need to communicate with the flight crew aboard SSF, the general interconnect architecture of the PIs' communication linkage is considered here. Key human factor design elements of this plan include: a candidate facility layout which accommodates three (3), multipurpose, rapidly reconfigurable work areas (suites) and consequent user traffic flow considerations, a multimedia telecommunications support capability, functional (human) traffic flow, optimized internal illumination and acoustics requirements, selected volumetric and safety requirements, and other architectural design parameters.

  1. A systems approach for designing a radio station layout for the U.S. National Airspace

    NASA Astrophysics Data System (ADS)

    Boci, Erton S.

    Today's National Airspace System (NAS) is managed using an aging surveillance radar system. Current radar technology is not adequate to sustain the rapid growth of the commercial, civil, and federal aviation sectors and cannot be adapted to use emerging 21st century airspace surveillance technologies. With 87,000 flights to manage per day, America's ground based radar system has hit a growth ceiling. Consequently, the FAA has embarked on a broad-reaching effort called the Next Generation Air Transportation System (NextGen) that seeks to transform today's aviation airspace management and ensure increased safety and capacity in our NAS. This dissertation presents a systems approach to Service Volume (SV) engineering, a relatively new field of engineering that has emerged in support of the FAA's Automatic Dependent Surveillance -- Broadcast (ADS-B) Air Traffic Modernization Program. SV Engineering is responsible for radio station layout design that would provide the required radio frequency (RF) coverage over a set of Service Volumes, each which represents a section of controlled airspace that is served by a particular air control facility or service. The radio station layout must be optimized to meet system performance, safety, and interference requirements while minimizing the number of radio station sites required to provide RF coverage of the entire airspace of the Unites States. The interference level requirements at the victim (of interference) receivers are the most important and stringent requirements imposed on the ADS-B radio station layout and configuration. In this dissertation, we show a novel and practical way to achieve this optimality by developing and employing several key techniques such as such as reverse radio line-of-site (RLOS) and complex entity-relationship modeling, to address the greater challenges of engineering this complex system. Given that numerous NAS radar facilities are clustered together in relative close proximity to each other, we

  2. DESIGNING AND OPPORTUNITY FUEL WITH BIOMASS AND TIRE-DERIVED FUEL FOR COFIRING AT WILLOW ISLAND GENERATING STATION AND COFIRING SAWDUST WITH COAL AT ALBRIGHT GENERATING STATION

    SciTech Connect

    K. Payette; D. Tillman

    2004-06-01

    During the period July 1, 2000-March 31, 2004, Allegheny Energy Supply Co., LLC (Allegheny) conducted an extensive demonstration of woody biomass cofiring at its Willow Island and Albright Generating Stations. This demonstration, cofunded by USDOE and Allegheny, and supported by the Biomass Interest Group (BIG) of EPRI, evaluated the impacts of sawdust cofiring in both cyclone boilers and tangentially-fired pulverized coal boilers. The cofiring in the cyclone boiler--Willow Island Generating Station Unit No.2--evaluated the impacts of sawdust alone, and sawdust blended with tire-derived fuel. The biomass was blended with the coal on its way to the combustion system. The cofiring in the pulverized coal boiler--Albright Generating Station--evaluated the impact of cofiring on emissions of oxides of nitrogen (NO{sub x}) when the sawdust was injected separately into the furnace. The demonstration of woody biomass cofiring involved design, construction, and testing at each site. The results addressed impacts associated with operational issues--capacity, efficiency, and operability--as well as formation and control of airborne emissions such as NO{sub x}, sulfur dioxide (SO{sub 2}2), opacity, and mercury. The results of this extensive program are detailed in this report.

  3. DESIGNING AN OPPORTUNITY FUEL WITH BIOMASS AND TIRE-DERIVED FUEL FOR COFIRING AT WILLOW ISLAND GENERATING STATION AND COFIRING SAWDUST WITH COAL AT ALBRIGHT GENERATING STATION

    SciTech Connect

    K. Payette; D. Tillman

    2002-01-01

    During the period October 1, 2001--December 31, 2001, Allegheny Energy Supply Co., LLC (Allegheny) completed construction of the Willow Island cofiring project. This included completion of the explosion proof electrical wiring, the control system, and the control software. Procedures for system checkout, shakedown, and initial operation were initiated during this period. During this time period the 100-hour test of the Albright Generating Station cofiring facility was completed. The testing demonstrated that cofiring at the Albright Generating Station could reliably contribute to a ''4P Strategy''--reduction of SO{sub 2}, NO{sub x}, mercury, and greenhouse gas emissions over a significant load range. During this period of time Allegheny Energy conducted facility tours of both Albright and Willow Island for the Biomass Interest Group of the Electric Power Research Institute. This report summarizes the activities associated with the Designer Opportunity Fuel program, and demonstrations at Willow Island and Albright Generating Stations. It details the completion of construction activities at the Willow Island site along with the 100-hr test at the Albright site.

  4. Analysis, control and design of a non-inverting buck-boost converter: A bump-less two-level T-S fuzzy PI control.

    PubMed

    Almasi, Omid Naghash; Fereshtehpoor, Vahid; Khooban, Mohammad Hassan; Blaabjerg, Frede

    2017-03-01

    In this paper, a new modified fuzzy Two-Level Control Scheme (TLCS) is proposed to control a non-inverting buck-boost converter. Each level of fuzzy TLCS consists of a tuned fuzzy PI controller. In addition, a Takagi-Sugeno-Kang (TSK) fuzzy switch proposed to transfer the fuzzy PI controllers to each other in the control system. The major difficulty in designing fuzzy TLCS which degrades its performance is emerging unwanted drastic oscillations in the converter output voltage during replacing the controllers. Thereby, the fuzzy PI controllers in each level of TLCS structure are modified to eliminate these oscillations and improve the system performance. Some simulations and digital signal processor based experiments are conducted on a non-inverting buck-boost converter to support the effectiveness of the proposed TLCS in controlling the converter output voltage.

  5. A Ten-Meter Ground-Station Telescope for Deep-Space Optical Communications: A Preliminary Design

    NASA Technical Reports Server (NTRS)

    Britcliffe, M.; Hoppe, D.; Roberts, W.; Page, N.

    2001-01-01

    This article describes a telescope design for a 10-m optical ground station for deep-space communications. The design for a direct-detection optical communications telescope differs dramatically from a telescope for imaging applications. In general, the requirements for optical manufacturing and tracking performance are much less stringent for direct detection of optical signals. The technical challenge is providing a design that will operate in the daytime/nighttime conditions required for a Deep Space Network tracking application. The design presented addresses these requirements. The design will provide higher performance at lower cost than existing designs.

  6. Design of the dual-buoy wave energy converter based on actual wave data of East Sea

    NASA Astrophysics Data System (ADS)

    Kim, Jeongrok; Kweon, Hyuck-Min; Jeong, Weon-Mu; Cho, Il-Hyoung; Cho, Hong-Yeon

    2015-07-01

    A new conceptual dual-buoy Wave Energy Converter (WEC) for the enhancement of energy extraction efficiency is suggested. Based on actual wave data, the design process for the suggested WEC is conducted in such a way as to ensure that it is suitable in real sea. Actual wave data measured in Korea's East Sea (position: 36.404 N° and 129.274 E°) from May 1, 2002 to March 29, 2005 were used as the input wave spectrum for the performance estimation of the dual-buoy WEC. The suggested WEC, a point absorber type, consists of two concentric floating circular cylinders (an inner and a hollow outer buoy). Multiple resonant frequencies in proposed WEC affect the Power Ttake-off (PTO) performance of the WEC. Based on the numerical results, several design strategies are proposed to further enhance the extraction efficiency, including intentional mismatching among the heave natural frequencies of dual buoys, the natural frequency of the internal fluid, and the peak frequency of the input wave spectrum.

  7. Field estimates of gravity terrain corrections and Y2K-compatible method to convert from gravity readings with multiple base stations to tide- and long-term drift-corrected observations

    USGS Publications Warehouse

    Plouff, Donald

    2000-01-01

    Gravity observations are directly made or are obtained from other sources by the U.S. Geological Survey in order to prepare maps of the anomalous gravity field and consequently to interpret the subsurface distribution of rock densities and associated lithologic or geologic units. Observations are made in the field with gravity meters at new locations and at reoccupations of previously established gravity "stations." This report illustrates an interactively-prompted series of steps needed to convert gravity "readings" to values that are tied to established gravity datums and includes computer programs to implement those steps. Inasmuch as individual gravity readings have small variations, gravity-meter (instrument) drift may not be smoothly variable, and acommodations may be needed for ties to previously established stations, the reduction process is iterative. Decision-making by the program user is prompted by lists of best values and graphical displays. Notes about irregularities of topography, which affect the value of observed gravity but are not shown in sufficient detail on topographic maps, must be recorded in the field. This report illustrates ways to record field notes (distances, heights, and slope angles) and includes computer programs to convert field notes to gravity terrain corrections. This report includes approaches that may serve as models for other applications, for example: portrayal of system flow; style of quality control to document and validate computer applications; lack of dependence on proprietary software except source code compilation; method of file-searching with a dwindling list; interactive prompting; computer code to write directly in the PostScript (Adobe Systems Incorporated) printer language; and high-lighting the four-digit year on the first line of time-dependent data sets for assured Y2K compatibility. Computer source codes provided are written in the Fortran scientific language. In order for the programs to operate, they first

  8. The use of multidimensional scaling for facilities layout - An application to the design of the Space Station

    NASA Technical Reports Server (NTRS)

    Tullis, Thomas S.; Bied Sperling, Barbra; Steinberg, A. L.

    1986-01-01

    Before an optimum layout of the facilities for the proposed Space Station can be designed, it is necessary to understand the functions that will be performed by the Space Station crew and the relationships among those functions. Five criteria for assessing functional relationships were identified. For each of these criteria, a matrix representing the degree of association of all pairs of functions was developed. The key to making inferences about the layout of the Space Station from these matrices was the use of multidimensional scaling (MDS). Applying MDS to these matrices resulted in spatial configurations of the crew functions in which smaller distances in the MDS configuration reflected closer associations. An MDS analysis of a composite matrix formed by combining the five individual matrices resulted in two dimensions that describe the configuration: a 'private-public' dimension and a 'group-individual' dimension. Seven specific recommendations for Space Station layout were derived from analyses of the MDS configurations. Although these techniques have been applied to the design of the Space Station, they can be applied to the design of any facility where people live or work.

  9. NASA Virtual Glovebox (VBX): Emerging Simulation Technology for Space Station Experiment Design, Development, Training and Troubleshooting

    NASA Technical Reports Server (NTRS)

    Smith, Jeffrey D.; Twombly, I. Alexander; Maese, A. Christopher; Cagle, Yvonne; Boyle, Richard

    2003-01-01

    The International Space Station demonstrates the greatest capabilities of human ingenuity, international cooperation and technology development. The complexity of this space structure is unprecedented; and training astronaut crews to maintain all its systems, as well as perform a multitude of research experiments, requires the most advanced training tools and techniques. Computer simulation and virtual environments are currently used by astronauts to train for robotic arm manipulations and extravehicular activities; but now, with the latest computer technologies and recent successes in areas of medical simulation, the capability exists to train astronauts for more hands-on research tasks using immersive virtual environments. We have developed a new technology, the Virtual Glovebox (VGX), for simulation of experimental tasks that astronauts will perform aboard the Space Station. The VGX may also be used by crew support teams for design of experiments, testing equipment integration capability and optimizing the procedures astronauts will use. This is done through the 3D, desk-top sized, reach-in virtual environment that can simulate the microgravity environment in space. Additional features of the VGX allow for networking multiple users over the internet and operation of tele-robotic devices through an intuitive user interface. Although the system was developed for astronaut training and assisting support crews, Earth-bound applications, many emphasizing homeland security, have also been identified. Examples include training experts to handle hazardous biological and/or chemical agents in a safe simulation, operation of tele-robotic systems for assessing and diffusing threats such as bombs, and providing remote medical assistance to field personnel through a collaborative virtual environment. Thus, the emerging VGX simulation technology, while developed for space- based applications, can serve a dual use facilitating homeland security here on Earth.

  10. Design and Demonstration of a Material-Plasma Exposure Target Station for Neutron Irradiated Samples

    SciTech Connect

    Rapp, Juergen; Aaron, A. M.; Bell, Gary L.; Burgess, Thomas W.; Ellis, Ronald James; Giuliano, D.; Howard, R.; Kiggans, James O.; Lessard, Timothy L.; Ohriner, Evan Keith; Perkins, Dale E.; Varma, Venugopal Koikal

    2015-10-20

    Fusion energy is the most promising energy source for the future, and one of the most important problems to be solved progressing to a commercial fusion reactor is the identification of plasma-facing materials compatible with the extreme conditions in the fusion reactor environment. The development of plasma–material interaction (PMI) science and the technology of plasma-facing components are key elements in the development of the next step fusion device in the United States, the so-called Fusion Nuclear Science Facility (FNSF). All of these PMI issues and the uncertain impact of the 14-MeV neutron irradiation have been identified in numerous expert panel reports to the fusion community. The 2007 Greenwald report classifies reactor plasma-facing materials (PFCs) and materials as the only Tier 1 issues, requiring a “. . . major extrapolation from the current state of knowledge, need for qualitative improvements and substantial development for both the short and long term.” The Greenwald report goes on to list 19 gaps in understanding and performance related to the plasma–material interface for the technology facilities needed for DEMO-oriented R&D and DEMO itself. Of the 15 major gaps, six (G7, G9, G10, G12, G13) can possibly be addressed with ORNL’s proposal of an advanced Material Plasma Exposure eXperiment. Establishing this mid-scale plasma materials test facility at ORNL is a key element in ORNL’s strategy to secure a leadership role for decades of fusion R&D. That is to say, our end goal is to bring the “signature facility” FNSF home to ORNL. This project is related to the pre-conceptual design of an innovative target station for a future Material–Plasma Exposure eXperiment (MPEX). The target station will be designed to expose candidate fusion reactor plasma-facing materials and components (PFMs and PFCs) to conditions anticipated in fusion reactors, where PFCs will be exposed to dense high-temperature hydrogen plasmas providing steady

  11. International Space Station USOS Potable Water Dispenser On-Orbit Functionality vs Design

    NASA Technical Reports Server (NTRS)

    Toon, Katherine P.; Lovell, Randal W.

    2009-01-01

    The International Space Station (ISS) currently provides potable water dispensing for rehydrating crewmembers food and drinking packages with one system located in the United States On-orbit Segment (USOS) and one system in the Russian Segment. The USOS Potable Water Dispenser (PWD) was delivered to ISS on ULF2, Shuttle Mission STS-126, and was subsequently activated in November 2008. The PWD activation on ISS is capable of supporting an ISS crew of six but nominally supplies only half the crew. The PWD is designed to provide incremental quantities of hot and ambient temperature potable water to US style food packages. PWD receives iodinated water from the US Laboratory Fuel Cell Water Bus, which is fed from the Water Processing Assembly (WPA). The PWD removes the biocidal iodine to make the water potable prior to dispensing. A heater assembly contained within the unit supplies up to 2.0 liters of hot water (65 to 93oC) every thirty minutes. This quantity supports three to four crewmembers to rehydrate their food and beverages from this location during a single meal. The unit is designed to remain functional for up to ten years with replacement of limited life items such as filters. To date, the PWD on-orbit performance has been acceptable. Since activation of the PWD, there have been several differences between on-orbit functionality and expected performance of hardware design. The comparison of on-orbit functionality to performance of hardware design is outlined for the following key areas: microbiology, PWD to food package water leakage, no-dispense scenarios, under-dispense scenarios, and crewmember feedback on actual on-orbit use.

  12. International Space Station USOS Potable Water Dispenser On-Orbit Functionality Versus Design

    NASA Technical Reports Server (NTRS)

    Toon, Katherine P.; Lovell, Randal W.

    2010-01-01

    The International Space Station (ISS) currently provides potable water dispensing for rehydrating crewmember food and drinking packages. There is one system located in the United States On-orbit Segment (USOS) and one system in the Russian Segment. Shuttle mission STS-126 delivered the USOS Potable Water Dispenser (PWD) to ISS on ULF2; subsequent activation occurred on November 2008. The PWD is capable of supporting an ISS crew of six, but nominally supplies only half this crew size. The PWD design provides incremental quantities of hot and ambient temperature potable water to US food and beverage packages. PWD receives iodinated water from the US Water Recovery System (WRS) Fuel Cell Water Bus, which feeds from the Water Processing Assembly (WPA). The PWD removes the biocidal iodine to make the water potable prior to dispensing. A heater assembly contained within the unit supplies up to 2.0 L of hot water (65 to 93 ?C) every 30 min. During a single meal, this quantity of water supports three to four crewmembers? food rehydration and beverages. The unit design has a functional life expectancy of 10 years, with replacement of limited life items, such as filters. To date, the PWD on-orbit performance is acceptable. Since activation of the PWD, there were several differences between on-orbit functionality and expected performance of hardware design. The comparison of on-orbit functionality to performance of hardware design is discussed for the following key areas: 1) microbial contamination, 2) no-dispense and water leakage scenarios, and 3) under-dispense scenarios.

  13. A Human Centred Interior Design of a Habitat Module for the International Space Station

    NASA Astrophysics Data System (ADS)

    Burattini, C.

    Since the very beginning of Space exploration, the interiors of a space habitat had to meet technological and functional requirements. Space habitats have now to meet completely different requirements related to comfort or at least to liveable environments. In order to reduce psychological drawbacks afflicting the crew during long periods of isolation in an extreme environment, one of the most important criteria is to assure high habitability levels. As a result of the Transhab project cancellation, the International Space Station (ISS) is actually made up of several research laboratories, but it has only one module for housing. This is suitable for short-term missions; middle ­ long stays require new solutions in terms of public and private spaces, as well as personal compartments. A design concept of a module appositely fit for living during middle-long stays aims to provide ISS with a place capable to satisfy habitability requirements. This paper reviews existing Space habitats and crew needs in a confined and extreme environment. The paper then describes the design of a new and human centred approach to habitation module typologies.

  14. International Space Station USOS Crew Quarters Ventilation and Acoustic Design Implementation

    NASA Technical Reports Server (NTRS)

    Broyan, James Lee, Jr.

    2009-01-01

    The International Space Station (ISS) United States Operational Segment (USOS) has four permanent rack sized ISS Crew Quarters (CQ) providing a private crewmember space. The CQ uses Node 2 cabin air for ventilation/thermal cooling, as opposed to conditioned ducted air from the ISS Temperature Humidity Control System or the ISS fluid cooling loop connections. Consequently, CQ can only increase the air flow rate to reduce the temperature delta between the cabin and the CQ interior. However, increasing airflow causes increased acoustic noise so efficient airflow distribution is an important design parameter. The CQ utilized a two fan push-pull configuration to ensure fresh air at the crewmember s head position and reduce acoustic exposure. The CQ interior needs to be below Noise Curve 40 (NC-40). The CQ ventilation ducts are open to the significantly louder Node 2 cabin aisle way which required significantly acoustic mitigation controls. The design implementation of the CQ ventilation system and acoustic mitigation are very inter-related and require consideration of crew comfort balanced with use of interior habitable volume, accommodation of fan failures, and possible crew uses that impact ventilation and acoustic performance. This paper illustrates the types of model analysis, assumptions, vehicle interactions, and trade-offs required for CQ ventilation and acoustics. Additionally, on-orbit ventilation system performance and initial crew feedback is presented. This approach is applicable to any private enclosed space that the crew will occupy.

  15. Convertible Stadium

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Air flotation technology used in NASA's Apollo program has found an interesting application in Hawaii's Aloha Stadium near Honolulu. The stadium's configuration can be changed, by moving entire 7,000-seat sections on a cushion of air, for best accommodation of spectators and participants at different types of events. In most stadiums, only a few hundred seats can be moved, by rolling sections on wheels or rails. At Aloha Stadium, 28,000 of the 50,000 seats can be repositioned for better spectator viewing and, additionally, for improved playing conditions. For example, a stadium designed primarily for football may compromise the baseball diamond by providing only a shallow outfield. Aloha's convertibility allows a full-size baseball field as well as optimum configurations for many other types of sports and special events. The photos show examples. The stadium owes its versatility to air flotation technology developed by General Motors. Its first large-scale application was movement of huge segments of the mammoth Saturn V moonbooster during assembly operations at Marshall Space Flight Center.

  16. A Camera and Multi-Sensor Automated Station Design for Polar Physical and Biological Systems Monitoring: AMIGOS

    NASA Astrophysics Data System (ADS)

    Bohlander, J. A.; Ross, R.; Scambos, T.; Haran, T. M.; Bauer, R. J.

    2012-12-01

    The Automated Meteorology - Ice/Indigenous species - Geophysics Observation System (AMIGOS) consists of a set of measurement instruments and camera(s) controlled by a single-board computer with a simplified Linux operating system and an Iridium satellite modem supporting two-way communication. Primary features of the system relevant to polar operations are low power requirements, daily data uploading, reprogramming, tolerance for low temperatures, and various approaches for automatic resets and recovery from low power or cold shut-down. Instruments include a compact weather station, C/A or dual-frequency GPS, solar flux and reflectivity sensors, sonic snow gages, simplified radio-echo-sounder, and resistance thermometer string in the firn column. In the current state of development, there are two basic designs. One is intended for in situ observations of glacier conditions. The other design supports a high-resolution camera for monitoring biological or geophysical systems from short distances (100 m to 20 km). The stations have been successfully used in several locations for operational support, monitoring rapid ice changes in response to climate change or iceberg drift, and monitoring penguin colony activity. As of June, 2012, there are 9 AMIGOS systems installed, all on the Antarctic continent. The stations are a working prototype for a planned series of upgraded stations, currently termed 'Sentinels'. These stations would carry further instrumentation, communications, and processing capability to investigate ice - ocean interaction from ice tongue, ice shelf, or fjord coastline areas.

  17. Laser Station Design for the Global Light System for the Planned JEM-EUSO Extreme Universe Observatory

    NASA Astrophysics Data System (ADS)

    Geier, Christine; Burg, Martin; Bigler, Colton; Wiencke, Lawrence

    2014-03-01

    The JEM-EUSO Global Light System (GLS) will provide ground-based calibration and monitoring for the JEM-EUSO detector planned for the International Space Station (ISS). JEM-EUSO will use the atmosphere as a giant calorimeter to measure Ultra High Energy Cosmic Rays (UHECRs). The GLS will include twelve ground stations. All twelve will have calibration xenon flash bulbs and six will have steered lasers. The GLS laser stations will generate optical signatures by creating light tracks across the JEM-EUSO field of view. The lasers and xenon flashers will be used to benchmark the JEM-EUSO instrument during its mission since energy, duration and orientation of those sources can be controlled. In this presentation, we will describe a project to design and build a working prototype of a GLS laser station. In order to meet the specifications set forth in the design requirements, our design incorporates remote operation capability, solar power, and a controlled internal climate. These components are in addition to the laser and calibration system and steering mechanism. All components will be combined in a robust, durable design that can be deployed and operated in remote locations across the globe.

  18. 78 FR 22529 - Information on Surplus Land at a Military Installation Designated for Disposal: Naval Air Station...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-16

    ... Department of the Navy Information on Surplus Land at a Military Installation Designated for Disposal: Naval...: This notice provides information on withdrawal of surplus property at Naval Air Station Alameda, Alameda, California. FOR FURTHER INFORMATION CONTACT: Ms. Laura Duchnak, Director, Naval...

  19. Instructor/Operator Station Design Handbook for Aircrew Training Devices. Final Technical Report for Period March 1982-December 1986.

    ERIC Educational Resources Information Center

    Warner, H. D.

    Human engineering guidelines for the design of instructor/operator stations (IOSs) for aircrew training devices are provided in this handbook. These guidelines specify the preferred configuration of IOS equipment across the range of the anticipated user sizes and performance capabilities. The guidelines are consolidated from various human…

  20. 49 CFR 37.49 - Designation of responsible person(s) for intercity and commuter rail stations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 1 2012-10-01 2012-10-01 false Designation of responsible person(s) for intercity and commuter rail stations. 37.49 Section 37.49 Transportation Office of the Secretary of Transportation TRANSPORTATION SERVICES FOR INDIVIDUALS WITH DISABILITIES (ADA) Transportation Facilities §...

  1. 49 CFR 37.49 - Designation of responsible person(s) for intercity and commuter rail stations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 1 2011-10-01 2011-10-01 false Designation of responsible person(s) for intercity and commuter rail stations. 37.49 Section 37.49 Transportation Office of the Secretary of Transportation TRANSPORTATION SERVICES FOR INDIVIDUALS WITH DISABILITIES (ADA) Transportation Facilities §...

  2. 49 CFR 37.49 - Designation of responsible person(s) for intercity and commuter rail stations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 1 2013-10-01 2013-10-01 false Designation of responsible person(s) for intercity and commuter rail stations. 37.49 Section 37.49 Transportation Office of the Secretary of Transportation TRANSPORTATION SERVICES FOR INDIVIDUALS WITH DISABILITIES (ADA) Transportation Facilities §...

  3. 49 CFR 37.49 - Designation of responsible person(s) for intercity and commuter rail stations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 1 2014-10-01 2014-10-01 false Designation of responsible person(s) for intercity and commuter rail stations. 37.49 Section 37.49 Transportation Office of the Secretary of Transportation TRANSPORTATION SERVICES FOR INDIVIDUALS WITH DISABILITIES (ADA) Transportation Facilities §...

  4. 49 CFR 37.49 - Designation of responsible person(s) for intercity and commuter rail stations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Designation of responsible person(s) for intercity and commuter rail stations. 37.49 Section 37.49 Transportation Office of the Secretary of Transportation TRANSPORTATION SERVICES FOR INDIVIDUALS WITH DISABILITIES (ADA) Transportation Facilities §...

  5. Design of Peptide Substrate for Sensitively and Specifically Detecting Two Aβ-Degrading Enzymes: Neprilysin and Angiotensin-Converting Enzyme.

    PubMed

    Chen, Po-Ting; Chen, Chao-Long; Lin, Lilian Tsai-Wei; Lo, Chun-Hsien; Hu, Chaur-Jong; Chen, Rita P-Y; Wang, Steven S-S

    2016-01-01

    Upregulation of neprilysin (NEP) to reduce Aβ accumulation in the brain is a promising strategy for the prevention of Alzheimer's disease (AD). This report describes the design and synthesis of a quenched fluorogenic peptide substrate qf-Aβ(12-16)AAC (with the sequence VHHQKAAC), which has a fluorophore, Alexa-350, linked to the side-chain of its C-terminal cysteine and a quencher, Dabcyl, linked to its N-terminus. This peptide emitted strong fluorescence upon cleavage. Our results showed that qf-Aβ(12-16)AAC is more sensitive to NEP than the previously reported peptide substrates, so that concentrations of NEP as low as 0.03 nM could be detected at peptide concentration of 2 μM. Moreover, qf-Aβ(12-16)AAC had superior enzymatic specificity for both NEP and angiotensin-converting enzyme (ACE), but was inert with other Aβ-degrading enzymes. This peptide, used in conjunction with a previously reported peptide substrate qf-Aβ(1-7)C [which is sensitive to NEP and insulin-degrading enzyme (IDE)], could be used for high-throughput screening of compounds that only upregulate NEP. The experimental results of cell-based activity assays using both qf-Aβ(1-7)C and qf-Aβ(12-16)AAC as the substrates confirm that somatostatin treatment most likely upregulates IDE, but not NEP, in neuroblastoma cells.

  6. Design of Peptide Substrate for Sensitively and Specifically Detecting Two Aβ-Degrading Enzymes: Neprilysin and Angiotensin-Converting Enzyme

    PubMed Central

    Chen, Po-Ting; Chen, Chao-Long; Lin, Lilian Tsai-Wei; Lo, Chun-Hsien; Hu, Chaur-Jong; Chen, Rita P.-Y.; Wang, Steven S.-S.

    2016-01-01

    Upregulation of neprilysin (NEP) to reduce Aβ accumulation in the brain is a promising strategy for the prevention of Alzheimer’s disease (AD). This report describes the design and synthesis of a quenched fluorogenic peptide substrate qf-Aβ(12–16)AAC (with the sequence VHHQKAAC), which has a fluorophore, Alexa-350, linked to the side-chain of its C-terminal cysteine and a quencher, Dabcyl, linked to its N-terminus. This peptide emitted strong fluorescence upon cleavage. Our results showed that qf-Aβ(12–16)AAC is more sensitive to NEP than the previously reported peptide substrates, so that concentrations of NEP as low as 0.03 nM could be detected at peptide concentration of 2 μM. Moreover, qf-Aβ(12–16)AAC had superior enzymatic specificity for both NEP and angiotensin-converting enzyme (ACE), but was inert with other Aβ-degrading enzymes. This peptide, used in conjunction with a previously reported peptide substrate qf-Aβ(1–7)C [which is sensitive to NEP and insulin-degrading enzyme (IDE)], could be used for high-throughput screening of compounds that only upregulate NEP. The experimental results of cell-based activity assays using both qf-Aβ(1–7)C and qf-Aβ(12–16)AAC as the substrates confirm that somatostatin treatment most likely upregulates IDE, but not NEP, in neuroblastoma cells. PMID:27096746

  7. Mixed inhibitors of angiotensin-converting enzyme and enkephalinase: Rational design, properties, and potential cardiovascular applications of glycopril and alatriopril

    SciTech Connect

    Gros, C.; Noel, N.; Souque, A.; Schwartz, J.C. ); Danvy, D.; Plaquevent, J.C.; Duhamel, L.; Duhamel, P. ); Lecomte, J.M. ); Bralet, J. )

    1991-05-15

    Angiotensin-converting enzyme (ACE) and enkephalinase, two cell surface metallopeptidases, are responsible for angiotensin II formation and atrial natriuretic factor (ANF) degradation, respectively, and thereby play a critical role in the metabolism of hormonal peptides exerting essentially opposite actions in cardiovascular regulations. To affect simultaneously both hormonal systems by a single molecular structure, the authors designed glycoprilat and alatrioprilat {l brace}(S)-N-(3-(3,4-methylenedioxyphenyl)-2-(mercaptomethyl)-1-oxopropyl)glycine and -alanine, respectively{r brace}. In vitro the two compounds inhibit both ACE and enkephalinase activities with similar, nanomolar potencies, and in vivo, glycopril and alatriopril, the corresponding diester prodrugs, occupy the two enzyme molecules in lung at similar low dosages. The high potency of these compounds is attributable to interaction of the methylenedioxy group with the S{sub 1} subsite of ACE and of the aromatic ring with the S{prime}{sub 1} subsite of enkephalinase. In rodents, low doses of these mixed inhibitors exert typical actions of ACE inhibitors--i.e., prevention of angiotensin I-induced hypertension-as well as of enkephalinase inhibitors--i.e., protection from {sup 125}I-ANF degradation or enhancement of diuresis and natriuresis following acute extracellular volume expansion. In view of the known counterbalanced physiological actions of the two hormonal peptides, whose metabolism is controlled by ACE and enkephalinase, mixed inhibitors of the two peptidases show promise for the treatment of various cardiovascular and salt-retention disorders.

  8. Conceptual design and evaluation of selected Space Station concepts, volume 1

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Space Station configuration concepts are defined to meet the NASA Headquarters Concept Development Group (CDG) requirements. Engineering and programmatic data are produced on these concepts suitable for NASA and industry dissemination. A data base is developed for input to the CDG's evaluation of generic Space Station configurations and for use in the critique of the CDG's generic configuration evaluation process.

  9. Design of a Remote Infrared Images and Other Data Acquisition Station for outdoor applications

    NASA Astrophysics Data System (ADS)

    Béland, M.-A.; Djupkep, F. B. D.; Bendada, A.; Maldague, X.; Ferrarini, G.; Bison, P.; Grinzato, E.

    2013-05-01

    The Infrared Images and Other Data Acquisition Station enables a user, who is located inside a laboratory, to acquire visible and infrared images and distances in an outdoor environment with the help of an Internet connection. This station can acquire data using an infrared camera, a visible camera, and a rangefinder. The system can be used through a web page or through Python functions.

  10. XTL Converter

    SciTech Connect

    Spurgeon, Steven R

    2015-10-07

    "XTL Converter" is a short Python script for electron microscopy simulation. The program takes an input crystal file in the VESTA *.XTL format and converts it to a text format readable by the multislice simulation program ìSTEM. The process of converting a crystal *.XTL file to the format used by the ìSTEM simulation program is quite tedious; it generally requires the user to select dozens or hundreds of atoms, rearranging and reformatting their position. Header information must also be reformatted to a specific style to be read by ìSTEM. "XTL Converter" simplifies this process, saving the user time and allowing for easy batch processing of crystals.

  11. Thermionic converter

    DOEpatents

    Fitzpatrick, G.O.

    1987-05-19

    A thermionic converter is set forth which includes an envelope having an electron collector structure attached adjacent to a wall. An electron emitter structure is positioned adjacent the collector structure and spaced apart from opposite wall. The emitter and collector structures are in a common chamber. The emitter structure is heated substantially only by thermal radiation. Very small interelectrode gaps can be maintained utilizing the thermionic converter whereby increased efficiency results. 10 figs.

  12. Use of Human Computer Models to Influence the Design of International Space Station Propulsion Module

    NASA Technical Reports Server (NTRS)

    Hamilton, George S.; Hall, Meridith L.

    1999-01-01

    The overall design for the International Space Station (ISS) Propulsion (Prop) Module consists of two bell shapes connected by a long tube having a shirt sleeve environment. The tube is to be used by the flight crew to transfer equipment and supplies from the Shuttle to ISS. Due to a desire to use existing space qualified hardware, the tube internal diameter was initially set at 38 inches, while the human engineering specification, NASA-STD-3000, required 50". Human computer modeling using the MannequinPro application was used to help make the case to enlarge the passageway to meet the specification. 3D CAD models of Prop Module were created with 38 inches, 45 inches and 50 inches passageways and human figures in the neutral body posture as well as a fetal posture were inserted into the model and systematically exercised. Results showed that only the 50 inches tube would accommodate a mid tube turn around by a large crew member, 95th percentile American males, by stature.

  13. Preliminary design, analysis, and costing of a dynamic scale model of the NASA space station

    NASA Technical Reports Server (NTRS)

    Gronet, M. J.; Pinson, E. D.; Voqui, H. L.; Crawley, E. F.; Everman, M. R.

    1987-01-01

    The difficulty of testing the next generation of large flexible space structures on the ground places an emphasis on other means for validating predicted on-orbit dynamic behavior. Scale model technology represents one way of verifying analytical predictions with ground test data. This study investigates the preliminary design, scaling and cost trades for a Space Station dynamic scale model. The scaling of nonlinear joint behavior is studied from theoretical and practical points of view. Suspension system interaction trades are conducted for the ISS Dual Keel Configuration and Build-Up Stages suspended in the proposed NASA/LaRC Large Spacecraft Laboratory. Key issues addressed are scaling laws, replication vs. simulation of components, manufacturing, suspension interactions, joint behavior, damping, articulation capability, and cost. These issues are the subject of parametric trades versus the scale model factor. The results of these detailed analyses are used to recommend scale factors for four different scale model options, each with varying degrees of replication. Potential problems in constructing and testing the scale model are identified, and recommendations for further study are outlined.

  14. Identification and status of design improvements to the NASA Shuttle EMU for International Space Station application.

    PubMed

    Wilde, R C; McBarron, J W; Faszcza, J J

    1997-06-01

    To meet the significant increase in EVA demand to support assembly and operations of the International Space Station (ISS), NASA and industry have improved the current Shuttle Extravehicular Mobility Unit (EMU), or "space suit", configuration to meet the unique and specific requirements of an orbital-based system. The current Shuttle EMU was designed to be maintained and serviced on the ground between frequent Shuttle flights. ISS will require the EMUs to meet increased EVAs out of the Shuttle Orbiter and to remain on orbit for up to 180 days without need for regular return to Earth for scheduled maintenance or refurbishment. Ongoing Shuttle EMU improvements have increased reliability, operational life and performance while minimizing ground and on-orbit maintenance cost and expendable inventory. Modifications to both the anthropomorphic mobility elements of the Space Suit Assembly (SSA) as well as to the Primary Life Support System (PLSS) are identified and discussed. This paper also addresses the status of on-going Shuttle EMU improvements and summarizes the approach for increasing interoperability of the U.S. and Russian space suits to be utilized aboard the ISS.

  15. Demonstration designs for the remediation of space debris from the International Space Station

    NASA Astrophysics Data System (ADS)

    Ebisuzaki, Toshikazu; Quinn, Mark N.; Wada, Satoshi; Piotrowski, Lech Wiktor; Takizawa, Yoshiyuki; Casolino, Marco; Bertaina, Mario E.; Gorodetzky, Philippe; Parizot, Etienne; Tajima, Toshiki; Soulard, Rémi; Mourou, Gérard

    2015-07-01

    We present here designs for a staged implementation of an orbiting debris remediation system comprised of a super-wide field-of-view telescope (EUSO) and a novel high efficiency fibre-based laser system (CAN). Initial proof of concept stages will operate from the International Space Station (ISS) where the EUSO telescope has been designed for operation as a detector of ultra-high energy cosmic rays. Equipped with 2.5 m optics and a field of view of ±30°, the EUSO telescope can also be utilised for the detection of high velocity fragmentation debris in orbit near the ISS. Further tracking, characterisation and remediation are to be performed by a CAN laser system operating in tandem with the EUSO telescope. For full scale versions of both instruments, the range of the detection/removal operation can be as large as 100 km. Utilising a step-by-step approach of increasing scale we present an analysis of implementation of: 1) Proof of principle demonstration of the detection by a mini-EUSO and operation of 100-fibre CAN laser technology as an ISS based prototype, 2) Technical demonstrator of debris-removal that consists of the EUSO telescope for the detection and a 10,000 fibre CAN laser for tracking and impulse delivery for debris re-entry, and 3) A free-flyer mission dedicated to debris remediation in a polar orbit with the altitude near 800 km. The integration of the two novel technologies aboard the ISS amounts to a novel approach as an immediate response to the serious space debris problem with the existing platform of ISS.

  16. Photovoltaic power system for satellite Earth stations in remote areas: Project status and design description

    NASA Technical Reports Server (NTRS)

    Delombard, R.

    1984-01-01

    A photovoltaic power system which will be installed at a remote location in Indonesia to provide power for a satellite Earth station and a classroom for video and audio teleconferences are described. The Earth station may also provide telephone service to a nearby village. The use of satellite communications for development assistance applications and the suitability of a hybrid photovoltaic engine generator power system for remote satellite Earth stations are demonstrated. The Indonesian rural satellite project is discussed and the photovoltaic power system is described.

  17. Research on design feasibility of high-power light-weight dc-to-dc converters for space power application

    NASA Technical Reports Server (NTRS)

    Wilson, T. G.

    1980-01-01

    The development of 5 kW converters with 100 kHz switching frequencies, consisting of two submodules each capable of 2.5 kW of output power, is discussed. Two semiconductor advances allowed increased power levels. Field effect transistors with ratings of 11 A and 400 V were operated in parallel to provide a converter output power of approximately 2000 W. Secondly, bipolar power switching transistor was operated in conjunction with a turn-off snubber circuit to provide converter output power levels approaching 1000 W. The interrelationships between mass, switching frequency, and efficiency were investigated. Converters were constructed for operation at a maximum output power level of 200 W, and a comparison was made for operation under similar input/output conditions for conversion frequencies of 20 kilohertz and 100 kilohertz. The effects of nondissipative turn-off snubber circuitry were also examined. Finally, a computerized instrumentation system allowing the measurement of pertinent converter operating conditions as well as the recording of converter waveforms is described.

  18. Preliminary designs for modular OTEC platform station-keeping subsystems. Final report. MR and S Report No. 6042-6

    SciTech Connect

    1980-02-29

    This volume of the report presents the results of the third through the sixth tasks of the Station Keeping Subsystem (SKSS) design studies for 10/40 MW/sub e/ capacity OTEC Modular Experiment platforms (MEP). Tasks 3 through 6 are: (3) complete preliminary designs for one SKSS for each of the two platforms (SPAR and BARGE); (4) development and testing recommendations for the MEP SKSS; (5) cost-time analysis; and (6) commercial plant recommendations. The overall conclusions and recommendations for the modular, as well as the commercial, OTEC platform station keeping subsystems are delineated. The basic design assumptions made during the process, the technical approach followed, and the results of design iterations, reliability and performance analyses are given. A complete description of the preliminary design SKSS concept is presented. The summary cost estimates for each of the alternative SKSS concepts considered are presented and a time schedule for the recommended concept is provided. The effects of varying some of the important parameters used in SKSS design on the performance and cost of the mooring system are investigated and results presented. The tests required and other developmental recommendations in order to verify and confirm the basic design assumptions are discussed. Finally, the experience gained in the MEP preliminary designs are extended to future commercial OTEC plants' SKSS designs. (WHK)

  19. Integrated Ultra-Wideband Tracking and Carbon Dioxide Sensing System Design for International Space Station Applications

    NASA Technical Reports Server (NTRS)

    Ni, Jianjun (David); Hafermalz, David; Dusl, John; Barton, Rick; Wagner, Ray; Ngo, Phong

    2015-01-01

    A three-dimensional (3D) Ultra-Wideband (UWB) Time-of-Arrival (TOA) tracking system has been studied at NASA Johnson Space Center (JSC) to provide the tracking capability inside the International Space Station (ISS) modules for various applications. One of applications is to locate and report the location where crew experienced possible high level of carbon-dioxide (CO2) and felt upset. Recent findings indicate that frequent, short-term crew exposure to elevated CO2 levels combined with other physiological impacts of microgravity may lead to a number of detrimental effects, including loss of vision. To evaluate the risks associated with transient elevated CO2 levels and design effective countermeasures, doctors must have access to frequent CO2 measurements in the immediate vicinity of individual crew members along with simultaneous measurements of their location in the space environment. To achieve this goal, a small, low-power, wearable system that integrates an accurate CO2 sensor with an ultra-wideband (UWB) radio capable of real-time location estimation and data communication is proposed. This system would be worn by crew members or mounted on a free-flyer and would automatically gather and transmit sampled sensor data tagged with real-time, high-resolution location information. Under the current proposed effort, a breadboard prototype of such a system has been developed. Although the initial effort is targeted to CO2 monitoring, the concept is applicable to other types of sensors. For the initial effort, a micro-controller is leveraged to integrate a low-power CO2 sensor with a commercially available UWB radio system with ranging capability. In order to accurately locate those places in a multipath intensive environment like ISS modules, it requires a robust real-time location system (RTLS) which can provide the required accuracy and update rate. A 3D UWB TOA tracking system with two-way ranging has been proposed and studied. The designed system will be tested

  20. Design of an integrated thermoelectric generator power converter for ultra-low power and low voltage body energy harvesters aimed at ExG active electrodes

    NASA Astrophysics Data System (ADS)

    Ataei, Milad; Robert, Christian; Boegli, Alexis; Farine, Pierre-André

    2015-10-01

    This paper describes a detailed design procedure for an efficient thermal body energy harvesting integrated power converter. The procedure is based on the examination of power loss and power transfer in a converter for a self-powered medical device. The efficiency limit for the system is derived and the converter is optimized for the worst case scenario. All optimum system parameters are calculated respecting the transducer constraints and the application form factor. Circuit blocks including pulse generators are implemented based on the system specifications and optimized converter working frequency. At this working condition, it has been demonstrated that the wide area capacitor of the voltage doubler, which provides high voltage switch gating, can be eliminated at the expense of wider switches. With this method, measurements show that 54% efficiency is achieved for just a 20 mV transducer output voltage and 30% of the chip area is saved. The entire electronic board can fit in one EEG or ECG electrode, and the electronic system can convert the electrode to an active electrode.

  1. Power quality control and design of power converter for variable-speed wind energy conversion system with permanent-magnet synchronous generator.

    PubMed

    Oğuz, Yüksel; Güney, İrfan; Çalık, Hüseyin

    2013-01-01

    The control strategy and design of an AC/DC/AC IGBT-PMW power converter for PMSG-based variable-speed wind energy conversion systems (VSWECS) operation in grid/load-connected mode are presented. VSWECS consists of a PMSG connected to a AC-DC IGBT-based PWM rectifier and a DC/AC IGBT-based PWM inverter with LCL filter. In VSWECS, AC/DC/AC power converter is employed to convert the variable frequency variable speed generator output to the fixed frequency fixed voltage grid. The DC/AC power conversion has been managed out using adaptive neurofuzzy controlled inverter located at the output of controlled AC/DC IGBT-based PWM rectifier. In this study, the dynamic performance and power quality of the proposed power converter connected to the grid/load by output LCL filter is focused on. Dynamic modeling and control of the VSWECS with the proposed power converter is performed by using MATLAB/Simulink. Simulation results show that the output voltage, power, and frequency of VSWECS reach to desirable operation values in a very short time. In addition, when PMSG based VSWECS works continuously with the 4.5 kHz switching frequency, the THD rate of voltage in the load terminal is 0.00672%.

  2. Power Quality Control and Design of Power Converter for Variable-Speed Wind Energy Conversion System with Permanent-Magnet Synchronous Generator

    PubMed Central

    Oğuz, Yüksel; Güney, İrfan; Çalık, Hüseyin

    2013-01-01

    The control strategy and design of an AC/DC/AC IGBT-PMW power converter for PMSG-based variable-speed wind energy conversion systems (VSWECS) operation in grid/load-connected mode are presented. VSWECS consists of a PMSG connected to a AC-DC IGBT-based PWM rectifier and a DC/AC IGBT-based PWM inverter with LCL filter. In VSWECS, AC/DC/AC power converter is employed to convert the variable frequency variable speed generator output to the fixed frequency fixed voltage grid. The DC/AC power conversion has been managed out using adaptive neurofuzzy controlled inverter located at the output of controlled AC/DC IGBT-based PWM rectifier. In this study, the dynamic performance and power quality of the proposed power converter connected to the grid/load by output LCL filter is focused on. Dynamic modeling and control of the VSWECS with the proposed power converter is performed by using MATLAB/Simulink. Simulation results show that the output voltage, power, and frequency of VSWECS reach to desirable operation values in a very short time. In addition, when PMSG based VSWECS works continuously with the 4.5 kHz switching frequency, the THD rate of voltage in the load terminal is 0.00672%. PMID:24453905

  3. IVA the robot: Design guidelines and lessons learned from the first space station laboratory manipulation system

    NASA Technical Reports Server (NTRS)

    Konkel, Carl R.; Powers, Allen K.; Dewitt, J. Russell

    1991-01-01

    The first interactive Space Station Freedom (SSF) lab robot exhibit was installed at the Space and Rocket Center in Huntsville, AL, and has been running daily since. IntraVehicular Activity (IVA) the robot is mounted in a full scale U.S. Lab (USL) mockup to educate the public on possible automation and robotic applications aboard the SSF. Responding to audio and video instructions at the Command Console, exhibit patrons may prompt IVA to perform a housekeeping task or give a speaking tour of the module. Other exemplary space station tasks are simulated and the public can even challenge IVA to a game of tic tac toe. In anticipation of such a system being built for the Space Station, a discussion is provided of the approach taken, along with suggestions for applicability to the Space Station Environment.

  4. Source of slow polarized positrons using the brilliant gamma beam at ELI-NP. Converter design and simulations

    NASA Astrophysics Data System (ADS)

    Djourelov, Nikolay; Oprisa, Andreea; Leca, Victor

    2016-01-01

    Simulations of slow positron (es+) source based on interaction of a circularly polarized gamma beam with a W converter were performed. The aim of the study was to propose a converter geometry and to determine the expected slow positron beam intensity and its spot size, and the degree of positron spin polarization, as well. The Monte Carlo simulations by means of GEANT4 were used to estimate the fast positron production and the moderation efficiency of the converter working as a self-moderator, as well. Finite element analysis by means of COMSOL Multiphysics was applied to calculate the fraction of extracted moderated positrons from the converter cells and the quality of the beam formation by focusing. Using the low energy (<3.5 MeV) gamma beam at ELI-NP with intensity of 2.4×1010γ/s the production of a slow positron beam with intensity of 1-2×106 es+/s is predicted. For the optimized converter geometry and in case of 100% circular polarization of the gammas the degree of spin polarization of the slow positron beam is expected to be 33%.

  5. Space Station Furnace Facility Core. Requirements definition and conceptual design study. Volume 2: Technical report. Appendix 6: Technical summary reports

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The Space Station Furnace Facility (SSFF) is a modular facility for materials research in the microgravity environment of the Space Station Freedom (SSF). The SSFF is designed for crystal growth and solidification research in the fields of electronic and photonic materials, metals and alloys, and glasses and ceramics and will allow for experimental determination of the role of gravitational forces in the solidification process. The facility will provide a capability for basic scientific research and will evaluate the commercial viability of low-gravity processing of selected technologically important materials. The facility is designed to support a complement of furnace modules as outlined in the Science Capabilities Requirements Document (SCRD). The SSFF is a three rack facility that provides the functions, interfaces, and equipment necessary for the processing of the furnaces and consists of two main parts: the SSFF Core Rack and the two Experiment Racks. The facility is designed to accommodate two experimenter-provided furnace modules housed within the two experiment racks, and is designed to operate these two furnace modules simultaneously. The SCRD specifies a wide range of furnace requirements and serves as the basis for the SSFF conceptual design. SSFF will support automated processing during the man-tended operations and is also designed for crew interface during the permanently manned configuration. The facility is modular in design and facilitates changes as required, so the SSFF is adept to modifications, maintenance, reconfiguration, and technology evolution.

  6. Cardiovascular research in space - Considerations for the design of the human research facility of the United States Space Station

    NASA Technical Reports Server (NTRS)

    Charles, J. B.; Bungo, M. W.

    1986-01-01

    The design of the Space Station's Human Research Facility for the collection of information on the long-time physiological adjustments of humans to space is described. The Space Life Sciences-1 mission will carry a rack-mounted echocardiograph for cardiac imaging, a mass spectrometer for cardiac output and respiratory function assessments at rest and during exercise, and a device to stimulate the carotid sinus baroreceptors and measure the resulting changes in heart rate.

  7. Space station WP-04 power system preliminary analysis and design document, volume 3

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Rocketdyne plans to generate a system level specification for the Space Station Electric Power System (EPS) in order to facilitate the usage, accountability, and tracking of overall system level requirements. The origins and status of the verification planning effort are traced and an overview of the Space Station program interactions are provided. The work package level interfaces between the EPS and the other Space Station work packages are outlined. A trade study was performed to determine the peaking split between PV and SD, and specifically to compare the inherent total peaking capability with proportionally shared peaking. In order to determine EPS cost drivers for the previous submittal of DRO2, the life cycle cost (LCC) model was run to identify the more significant costs and the factors contributing to them.

  8. Design, construction, and utilization of a space station assembled from 5-meter erectable struts

    NASA Technical Reports Server (NTRS)

    Mikulas, Martin M., Jr.; Bush, Harold G.

    1987-01-01

    The primary characteristics of the 5-meter erectable truss is presented, which was baselined for the Space Station. The relatively large 5-meter truss dimension was chosen to provide a deep beam for high bending stiffness yet provide convenient mounting locations for space shuttle cargo bay size payloads which are approx. 14.5 ft (4.4 m) in diameter. Truss nodes and quick attachment erectable joints are described which provide for evolutionary three dimensional growth and for simple maintenance and repair. A mobile remote manipulator system is described which is provided to assist in station construction and maintenance. A discussion is also presented of the construction of the Space Station and the associated extravehicular active (EVA) time.

  9. DESIGNING AN OPPORTUNITY FUEL WITH BIOMASS AND TIRE-DERIVED FUEL FOR COFIRING AT WILLOW ISLAND GENERATING STATION

    SciTech Connect

    K. Payette; D. Tillman

    2001-04-01

    During the period January 1, 2001-March 31, 2001, Allegheny Energy Supply Co., LLC (Allegheny) finalized the engineering of the Willow Island cofiring project, completed the fuel characterizations for both the Willow Island and Albright Generating Station projects, and initiated construction of both projects. Allegheny and its contractor, Foster Wheeler, selected appropriate fuel blends and issued purchase orders for all processing and mechanical equipment to be installed at both sites. This report summarizes the activities associated with the Designer Opportunity Fuel program, and demonstrations at Willow Island and Albright Generating Stations. The third quarter of the project involved completing the detailed designs for the Willow Island Designer Fuel project. It also included complete characterization of the coal and biomass fuels being burned, focusing upon the following characteristics: proximate and ultimate analysis; higher heating value; carbon 13 nuclear magnetic resonance testing for aromaticity, number of aromatic carbons per cluster, and the structural characteristics of oxygen in the fuel; drop tube reactor testing for high temperature devolatilization kinetics and generation of fuel chars; thermogravimetric analyses (TGA) for char oxidation kinetics; and related testing. The construction at both sites commenced during this quarter, and was largely completed at the Albright Generating Station site.

  10. System design analyses of a rotating advanced-technology space station for the year 2025

    NASA Technical Reports Server (NTRS)

    Queijo, M. J.; Butterfield, A. J.; Cuddihy, W. F.; Stone, R. W.; Wrobel, J. R.; Garn, P. A.; King, C. B.

    1988-01-01

    Studies of an advanced technology space station configured to implement subsystem technologies projected for availability in the time period 2000 to 2025 is documented. These studies have examined the practical synergies in operational performance available through subsystem technology selection and identified the needs for technology development. Further analyses are performed on power system alternates, momentum management and stabilization, electrothermal propulsion, composite materials and structures, launch vehicle alternates, and lunar and planetary missions. Concluding remarks are made regarding the advanced technology space station concept, its intersubsystem synergies, and its system operational subsystem advanced technology development needs.

  11. CETF Space Station payload pointing system design and analysis feasibility study. [Critical Evaluation Task Force

    NASA Technical Reports Server (NTRS)

    Smagala, Tom; Mcglew, Dave

    1988-01-01

    The expected pointing performance of an attached payload coupled to the Critical Evaluation Task Force Space Station via a payload pointing system (PPS) is determined. The PPS is a 3-axis gimbal which provides the capability for maintaining inertial pointing of a payload in the presence of disturbances associated with the Space Station environment. A system where the axes of rotation were offset from the payload center of mass (CM) by 10 in. in the Z axis was studied as well as a system having the payload CM offset by only 1 inch. There is a significant improvement in pointing performance when going from the 10 in. to the 1 in. gimbal offset.

  12. Hydrogen Filling Station

    SciTech Connect

    Boehm, Robert F; Sabacky, Bruce; Anderson II, Everett B; Haberman, David; Al-Hassin, Mowafak; He, Xiaoming; Morriseau, Brian

    2010-02-24

    future. Project partners also conducted a workshop on hydrogen safety and permitting. This provided an opportunity for the various permitting agencies and end users to gather to share experiences and knowledge. As a result of this workshop, the permitting process for the hydrogen filling station on the Las Vegas Valley Water District’s land was done more efficiently and those who would be responsible for the operation were better educated on the safety and reliability of hydrogen production and storage. The lessons learned in permitting the filling station and conducting this workshop provided a basis for future hydrogen projects in the region. Continuing efforts to increase the working pressure of electrolysis and efficiency have been pursued. Research was also performed on improving the cost, efficiency and durability of Proton Exchange Membrane (PEM) hydrogen technology. Research elements focused upon PEM membranes, electrodes/catalysts, membrane-electrode assemblies, seals, bipolar plates, utilization of renewable power, reliability issues, scale, and advanced conversion topics. Additionally, direct solar-to-hydrogen conversion research to demonstrate stable and efficient photoelectrochemistry (PEC) hydrogen production systems based on a number of optional concepts was performed. Candidate PEC concepts included technical obstacles such as inefficient photocatalysis, inadequate photocurrent due to non-optimal material band gap energies, rapid electron-hole recombination, reduced hole mobility and diminished operational lifetimes of surface materials exposed to electrolytes. Project Objective 1: Design, build, operate hydrogen filling station Project Objective 2: Perform research and development for utilizing solar technologies on the hydrogen filling station and convert two utility vehicles for use by the station operators Project Objective 3: Increase capacity of hydrogen filling station; add additional vehicle; conduct safety workshop; develop a roadmap for

  13. Rodent bone densitometer on the International Space Station: Instrument design and performance

    NASA Astrophysics Data System (ADS)

    Vellinger, John C.; Barton, Kenneth; Faget, Paul; Todd, Paul; Boland, Eugene

    2016-07-01

    The study of bone loss dynamics, mechanisms and countermeasures has been a publicly stated purpose of biomedical research aboard the International Space Station. Rodent research has always played a major role in terrestrial laboratories studying bone loss. The "gold standard" for assessing bone loss in human patients has been dual-energy x-ray absorptiometry (DEXA). DEXA is also widely applied to the study of bone loss in laboratory animals, so this technology has been added to the ISS inventory of analytical tools in the form of the ISS Bone Densitometer (BD) designed, constructed, tested and integrated by Techshot, Inc. (Greenville, Indiana, USA). The BD is a re-packaged COTS device known as PIXImus (GE-Lunar, USA), which was installed on ISS in November 2014 after launching on SpaceX-4. To facilitate operations in microgravity and to meet spaceflight facility and safety requirements the commercial x-ray source, control electronics and imaging system were modified and packaged by Techshot into a drawer that fits into a single EXPRESS Locker replacement. A space-rated "Exam Box" is also supplied for containment of the anesthetized subject during transfer into the BD and during exposure. The commercial software package controls four paired-energy exposures, 80 and 35 kV, and applies DEXA algorithms to the fluorescence images and displays bone mineral density (BMD), bone mineral content, lean mass, fat mass, total mass and per cent fat. The BD is therefore also a means for measuring mass and body composition making it a versatile tool for many types of rodent studies on orbit. The BD has been operated multiple times on orbit, and its performance has not differed significantly from its performance on the ground. It has been shown to measure body mass with a precision of +/- 0.1 g and on-orbit accuracy of -0.3 g. It is expected to detect BMD losses of approximately 2%. The image data are stored in a manner that allows post-test data analysis especially including the

  14. Flow Control and Design Assessment for Drainage System at McMurdo Station, Antarctica

    DTIC Science & Technology

    2014-11-24

    evaluating existing culvert and snow dump loca- tions at McMurdo Station. Flow modeling and structural analyses were conducted to determine de- sign...44 15 Ratio of the gravel’s bearing capacity to weir weight per area for...equipment manually clears major flow arteries in tight areas in anticipa- tion of the snowmelt runoff (Figure 1). Snowmelt runoff passes through

  15. Effects of Specifically Designed Literacy Stations on the Reading Fluency of Students

    ERIC Educational Resources Information Center

    English, Christine E.

    2013-01-01

    Reading fluency is critical in all aspects of school curriculum. Struggling readers fall further behind each year due to the increasing demands of the curriculum. To address this problem, the current study implemented literacy stations for struggling readers in a school in rural Washington State. The purpose of this study was to examine (a)…

  16. System Design and Wide-field Imaging Aspects of Synthesis Arrays with Phased Array Stations

    NASA Astrophysics Data System (ADS)

    Bregman, Jacob Dirk

    2012-12-01

    Dit proefschrift betreft het ontwerpen van synthese radiotelescopen, zoals LOFAR. Bekende ontwerpprincipes worden gecombineerd met een visie op technologische mogelijkheden die in de nabije toekomst binnen handbereik komen. De centrale vraag daarbij is hoe wetenschappelijke gebruikers met een gegeven budget een optimaal resultaat kunnen behalen. Systeemontwerp begint met een analyse van de fundamentele beperkingen van groothoek beeldvorming met apertuursynthese en van praktische beperkingen zoals verstoring door de ionosfeer. Deze analyse heeft geleid tot een aantal schaalwetten voor telescoop- en antenne-configuratie en voor de vereiste digitale processing. In een array antenne worden de signalen van een aantal antennes opgeteld tot een versterkt signaal uit een bepaalde richting. Deze array technologie geeft de mogelijkheid een gegeven aantal eenvoudige antennes optimaal te verdelen over een aantal stations. Ons onderzoek heeft laten zien dat de stations een minimum grootte nodig hebben om verstoring door de ionosfeer over het gehele beeldveld te kunnen corrigeren. Te kleine stations kunnen maar in een beperkt deel van hun grote beeldveld voldoende scherpte krijgen. Een te beperkt aantal stations leidt echter tot toename van ruis in het beeld die met extra beeldbewerking deels is te verwijderen. Een belangrijk resultaat van het werk is het ontwerp voor twee nieuwe methoden van beeldvorming waarbij de computer bewerking is teruggebracht tot een theoretisch minimum dat evenredig is met het oppervlak van het totale beeldveld gemeten in resolutie elementen. Voor een voldoend groot aantal stations is een optimale verdeling mogelijk waarmee maximale scherpte en minimale ruis is te realiseren binnen een totaal budget dat niet door de kosten van de benodigde computing faciliteiten wordt gedomineerd.

  17. Bidirectional DC/DC Converter

    NASA Astrophysics Data System (ADS)

    Pedersen, F.

    2008-09-01

    The presented bidirectional DC/DC converter design concept is a further development of an already existing converter used for low battery voltage operation.For low battery voltage operation a high efficient low parts count DC/DC converter was developed, and used in a satellite for the battery charge and battery discharge function.The converter consists in a bidirectional, non regulating DC/DC converter connected to a discharge regulating Buck converter and a charge regulating Buck converter.The Bidirectional non regulating DC/DC converter performs with relatively high efficiency even at relatively high currents, which here means up to 35Amps.This performance was obtained through the use of power MOSFET's with on- resistances of only a few mille Ohms connected to a special transformer allowing paralleling several transistor stages on the low voltage side of the transformer. The design is patent protected. Synchronous rectification leads to high efficiency at the low battery voltages considered, which was in the range 2,7- 4,3 Volt DC.The converter performs with low switching losses as zero voltage zero current switching is implemented in all switching positions of the converter.Now, the drive power needed, to switch a relatively large number of low Ohm , hence high drive capacitance, power MOSFET's using conventional drive techniques would limit the overall conversion efficiency.Therefore a resonant drive consuming considerable less power than a conventional drive circuit was implemented in the converter.To the originally built and patent protected bidirectional non regulating DC/DC converter, is added the functionality of regulation.Hereby the need for additional converter stages in form of a Charge Buck regulator and a Discharge Buck regulator is eliminated.The bidirectional DC/DC converter can be used in connection with batteries, motors, etc, where the bidirectional feature, simple design and high performance may be useful.

  18. Space station Simulation Computer System (SCS) study for NASA/MSFC. Volume 3: Refined conceptual design report

    NASA Technical Reports Server (NTRS)

    1989-01-01

    The results of the refined conceptual design phase (task 5) of the Simulation Computer System (SCS) study are reported. The SCS is the computational portion of the Payload Training Complex (PTC) providing simulation based training on payload operations of the Space Station Freedom (SSF). In task 4 of the SCS study, the range of architectures suitable for the SCS was explored. Identified system architectures, along with their relative advantages and disadvantages for SCS, were presented in the Conceptual Design Report. Six integrated designs-combining the most promising features from the architectural formulations-were additionally identified in the report. The six integrated designs were evaluated further to distinguish the more viable designs to be refined as conceptual designs. The three designs that were selected represent distinct approaches to achieving a capable and cost effective SCS configuration for the PTC. Here, the results of task 4 (input to this task) are briefly reviewed. Then, prior to describing individual conceptual designs, the PTC facility configuration and the SSF systems architecture that must be supported by the SCS are reviewed. Next, basic features of SCS implementation that have been incorporated into all selected SCS designs are considered. The details of the individual SCS designs are then presented before making a final comparison of the three designs.

  19. Space Station solar water heater

    NASA Technical Reports Server (NTRS)

    Horan, D. C.; Somers, Richard E.; Haynes, R. D.

    1990-01-01

    The feasibility of directly converting solar energy for crew water heating on the Space Station Freedom (SSF) and other human-tended missions such as a geosynchronous space station, lunar base, or Mars spacecraft was investigated. Computer codes were developed to model the systems, and a proof-of-concept thermal vacuum test was conducted to evaluate system performance in an environment simulating the SSF. The results indicate that a solar water heater is feasible. It could provide up to 100 percent of the design heating load without a significant configuration change to the SSF or other missions. The solar heater system requires only 15 percent of the electricity that an all-electric system on the SSF would require. This allows a reduction in the solar array or a surplus of electricity for onboard experiments.

  20. DESIGNING AN OPPORTUNITY FUEL WITH BIOMASS AND TIRE-DERIVED FUEL FOR COFIRING AT WILLOW ISLAND GENERATING STATION

    SciTech Connect

    K. Payette; D. Tillman

    2001-01-01

    During the period October 1, 2000 - December 31, 2000, Allegheny Energy Supply Co., LLC (Allegheny) executed a Cooperative Agreement with the National Energy Technology Laboratory to implement a major cofiring demonstration at the Willow Island Generating Station Boiler No.2. Willow Island Boiler No.2 is a cyclone boiler. Allegheny also will demonstrate separate injection cofiring at the Albright Generating Station Boiler No.3, a tangentially fired boiler. The Allegheny team includes Foster Wheeler as its primary subcontractor. Additional subcontractors are Cofiring Alternatives and N.S. Harding and Associates. This report summarizes the activities associated with the Designer Opportunity Fuel program, and demonstrations at Willow Island and Albright Generating Stations. The second quarter of the project involved completing the designs for each location. Further, geotechnical investigations proceeded at each site. Preparations were made to perform demolition on two small buildings at the Willow Island site. Fuels strategies were initiated for each site. Test planning commenced for each site. A groundbreaking ceremony was held at the Willow Island site on October 18, with Governor C. Underwood being the featured speaker.

  1. Lunar base thermoelectric power station study

    NASA Technical Reports Server (NTRS)

    Determan, William; Frye, Patrick; Mondt, Jack; Fleurial, Jean-Pierre; Johnson, Ken; Stapfer, G.; Brooks, Michael D.; Heshmatpour, Ben

    2006-01-01

    Under NASA's Project Prometheus, the Nuclear Systems Program, the Jet Propulsion Laboratory, Pratt & Whitney Rocketdyne, and Teledyne Energy Systems have teamed with a number of universities, under the Segmented Thermoelectric Multicouple Converter (STMC) program, to develop the next generation of advanced thermoelectric converters for space reactor power systems. Work on the STMC converter assembly has progressed to the point where the lower temperature stage of the segmented multicouple converter assembly is ready for laboratory testing and the upper stage materials have been identified and their properties are being characterized. One aspect of the program involves mission application studies to help define the potential benefits from the use of these STMC technologies for designated NASA missions such as the lunar base power station where kilowatts of power are required to maintain a permanent manned presence on the surface of the moon. A modular 50 kWe thermoelectric power station concept was developed to address a specific set of requirements developed for this mission. Previous lunar lander concepts had proposed the use of lunar regolith as in-situ radiation shielding material for a reactor power station with a one kilometer exclusion zone radius to minimize astronaut radiation dose rate levels. In the present concept, we will examine the benefits and requirements for a hermetically-sealed reactor thermoelectric power station module suspended within a man-made lunar surface cavity. The concept appears to maximize the shielding capabilities of the lunar regolith while minimizing its handling requirements. Both thermal and nuclear radiation levels from operation of the station, at its 100-m exclusion zone radius, were evaluated and found to be acceptable. Site preparation activities are reviewed and well as transport issues for this concept. The goal of the study was to review the entire life cycle of the unit to assess its technical problems and technology

  2. Lunar Base Thermoelectric Power Station Study

    NASA Astrophysics Data System (ADS)

    Determan, William; Frye, Patrick; Mondt, Jack; Fleurial, Jean-Pierre; Johnson, Ken; Stapfer, Gerhard; Brooks, Michael; Heshmatpour, Ben

    2006-01-01

    Under NASA's Project Prometheus, the Nuclear Space Power Systems Program, the Jet Propulsion Laboratory, Pratt & Whitney Rocketdyne, and Teledyne Energy Systems have teamed with a number of universities, under the Segmented Thermoelectric Multicouple Converter (STMC) Task, to develop the next generation of advanced thermoelectric converters for space reactor power systems. Work on the STMC converter assembly has progressed to the point where the lower temperature stage of the segmented multicouple converter assembly is ready for laboratory testing, and promising candidates for the upper stage materials have been identified and their properties are being characterized. One aspect of the program involves mission application studies to help define the potential benefits from the use of these STMC technologies for designated NASA missions such as a lunar base power station where kilowatts of power would be required to maintain a permanent manned presence on the surface of the moon. A modular 50 kWe thermoelectric power station concept was developed to address a specific set of requirements developed for this particular mission concept. Previous lunar lander concepts had proposed the use of lunar regolith as in-situ radiation shielding material for a reactor power station with a one kilometer exclusion zone radius to minimize astronaut radiation dose rate levels. In the present concept, we will examine the benefits and requirements for a hermetically-sealed reactor thermoelectric power station module suspended within a man-made lunar surface cavity. The concept appears to maximize the shielding capabilities of the lunar regolith while minimizing its handling requirements. Both thermal and nuclear radiation levels from operation of the station, at its 100-m exclusion zone radius, were evaluated and found to be acceptable. Site preparation activities are reviewed as well as transport issues for this concept. The goal of the study was to review the entire life cycle of the

  3. Lunar Base Thermoelectric Power Station Study

    SciTech Connect

    Determan, William; Frye, Patrick; Mondt, Jack; Fleurial, Jean-Pierre; Johnson, Ken; Stapfer, Gerhard; Brooks, Michael; Heshmatpour, Ben

    2006-01-20

    Under NASA's Project Prometheus, the Nuclear Space Power Systems Program, the Jet Propulsion Laboratory, Pratt and Whitney Rocketdyne, and Teledyne Energy Systems have teamed with a number of universities, under the Segmented Thermoelectric Multicouple Converter (STMC) Task, to develop the next generation of advanced thermoelectric converters for space reactor power systems. Work on the STMC converter assembly has progressed to the point where the lower temperature stage of the segmented multicouple converter assembly is ready for laboratory testing, and promising candidates for the upper stage materials have been identified and their properties are being characterized. One aspect of the program involves mission application studies to help define the potential benefits from the use of these STMC technologies for designated NASA missions such as a lunar base power station where kilowatts of power would be required to maintain a permanent manned presence on the surface of the moon. A modular 50 kWe thermoelectric power station concept was developed to address a specific set of requirements developed for this particular mission concept. Previous lunar lander concepts had proposed the use of lunar regolith as in-situ radiation shielding material for a reactor power station with a one kilometer exclusion zone radius to minimize astronaut radiation dose rate levels. In the present concept, we will examine the benefits and requirements for a hermetically-sealed reactor thermoelectric power station module suspended within a man-made lunar surface cavity. The concept appears to maximize the shielding capabilities of the lunar regolith while minimizing its handling requirements. Both thermal and nuclear radiation levels from operation of the station, at its 100-m exclusion zone radius, were evaluated and found to be acceptable. Site preparation activities are reviewed as well as transport issues for this concept. The goal of the study was to review the entire life cycle of

  4. Load estimator-based hybrid controller design for two-interleaved boost converter dedicated to renewable energy and automotive applications.

    PubMed

    Bougrine, Mohamed; Benmiloud, Mohammed; Benalia, Atallah; Delaleau, Emmanuel; Benbouzid, Mohamed

    2017-01-01

    This paper is devoted to the development of a hybrid controller for a two-interleaved boost converter dedicated to renewable energy and automotive applications. The control requirements, resumed in fast transient and low input current ripple, are formulated as a problem of fast stabilization of a predefined optimal limit cycle, and solved using hybrid automaton formalism. In addition, a real time estimation of the load is developed using an algebraic approach for online adjustment of the hybrid controller. Mathematical proofs are provided with simulations to illustrate the effectiveness and the robustness of the proposed controller despite different disturbances. Furthermore, a fuel cell system supplying a resistive load through a two-interleaved boost converter is also highlighted.

  5. Design and measurement of a TE13 input converter for high order mode gyrotron travelling wave amplifiers

    NASA Astrophysics Data System (ADS)

    Wang, Yan; Liu, Guo; Shu, Guoxiang; Yan, Ran; Wang, Li; Agurgo Balfour, E.; Fu, Hao; Luo, Yong; Wang, Shafei

    2016-03-01

    A technique to launch a circular TE13 mode to interact with the helical electron beam of a gyrotron travelling wave amplifier is proposed and verified by simulation and cold test in this paper. The high order (HOM) TE13 mode is excited by a broadband Y-type power divider with the aid of a cylindrical waveguide system. Using grooves and convex strips loaded at the lateral planes of the output cylindrical waveguide, the electric fields of the potential competing TE32 and TE71 modes are suppressed to allow the transmission of the dominant TE13 mode. The converter performance for different structural dimensions of grooves and convex strips is studied in detail and excellent results have been achieved. Simulation predicts that the average transmission is ˜-1.8 dB with a 3 dB bandwidth of 7.2 GHz (91.5-98.7 GHz) and port reflection is less than -15 dB. The conversion efficiency to the TE32 and TE71 modes are, respectively, under -15 dB and -24 dB in the operating frequency band. Such an HOM converter operating at W-band has been fabricated and cold tested with the radiation boundary. Measurement from the vector network analyzer cold test and microwave simulations show a good reflection performance for the converter.

  6. Status of the Space Station water reclamation and management subsystem design concept

    NASA Technical Reports Server (NTRS)

    Bagdigian, R. M.; Mortazavi, P. L.

    1987-01-01

    A development status report is presented for the NASA Space Station's water reclamation and management (WRM) system, for which the candidate phase change-employing processing technologies are an air evaporation subsystem, a thermoelectric integrated membrane evaporation subsystem, and the vapor compression distillation subsystem. These WRM candidates employ evaporation to effect water removal from contaminants, but differ in their control of the vapor/liquid interface in zero-gravity and in the recovery of the latent heat of vaporization.

  7. Design and development of a space station hazardous material system for assessing chemical compatibility

    NASA Technical Reports Server (NTRS)

    Congo, Richard T.

    1990-01-01

    As the Space Station nears reality in funding support from Congress, NASA plans to perform over a hundred different missions in the coming decade. Incrementally deployed, the Space Station will evolve into modules linked to an integral structure. Each module will have characteristic functions, such as logistics, habitation, and materials processing. Because the Space Station is to be user friendly for experimenters, NASA is anticipating that a variety of different chemicals will be taken on-board. Accidental release of these potentially toxic chemicals and their chemical compatibility is the focus of this discourse. The Microgravity Manufacturing Processing Facility (MMPF) will contain the various facilities within the U.S. Laboratory (USL). Each facility will have a characteristic purpose, such as alloy solidification or vapor crystal growth. By examining the proposed experiments for each facility, identifying the chemical constituents, their physical state and/or changes, byproducts and effluents, those payloads can be identified which may contain toxic, explosive, or reactive compounds that require processing or containment in mission peculiar waste management systems. Synergistic reactions from mixed effluent streams is of major concern. Each experiment will have it own data file, complete with schematic, chemical listing, physical data, etc. Chemical compatibility information from various databases will provide assistance in the analysis of alternate disposal techniques (pretreatment, separate storage, etc.). Along with data from the Risk Analysis of the Proposed USL Waste Management System, accidental release of potentially toxic and catastrophic chemicals would be eliminated or reduced.

  8. Space station data system analysis/architecture study. Task 2: Options development, DR-5. Volume 2: Design options

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The primary objective of Task 2 is the development of an information base that will support the conduct of trade studies and provide sufficient data to make key design/programmatic decisions. This includes: (1) the establishment of option categories that are most likely to influence Space Station Data System (SSDS) definition; (2) the identification of preferred options in each category; and (3) the characterization of these options with respect to performance attributes, constraints, cost and risk. This volume contains the options development for the design category. This category comprises alternative structures, configurations and techniques that can be used to develop designs that are responsive to the SSDS requirements. The specific areas discussed are software, including data base management and distributed operating systems; system architecture, including fault tolerance and system growth/automation/autonomy and system interfaces; time management; and system security/privacy. Also discussed are space communications and local area networking.

  9. The Influence of Microbiology on Spacecraft Design and Controls: A Historical Perspective of the Shuttle and International Space Station Programs

    NASA Technical Reports Server (NTRS)

    Castro, Victoria A.; Bruce, Rebekah J.; Ott, C. Mark; Pierson, D. L.

    2006-01-01

    For over 40 years, NASA has been putting humans safely into space in part by minimizing microbial risks to crew members. Success of the program to minimize such risks has resulted from a combination of engineering and design controls as well as active monitoring of the crew, food, water, hardware, and spacecraft interior. The evolution of engineering and design controls is exemplified by the implementation of HEPA filters for air treatment, antimicrobial surface materials, and the disinfection regimen currently used on board the International Space Station. Data from spaceflight missions confirm the effectiveness of current measures; however, fluctuations in microbial concentrations and trends in contamination events suggest the need for continued diligence in monitoring and evaluation as well as further improvements in engineering systems. The knowledge of microbial controls and monitoring from assessments of past missions will be critical in driving the design of future spacecraft.

  10. Robust Constrained Optimization Approach to Control Design for International Space Station Centrifuge Rotor Auto Balancing Control System

    NASA Technical Reports Server (NTRS)

    Postma, Barry Dirk

    2005-01-01

    This thesis discusses application of a robust constrained optimization approach to control design to develop an Auto Balancing Controller (ABC) for a centrifuge rotor to be implemented on the International Space Station. The design goal is to minimize a performance objective of the system, while guaranteeing stability and proper performance for a range of uncertain plants. The Performance objective is to minimize the translational response of the centrifuge rotor due to a fixed worst-case rotor imbalance. The robustness constraints are posed with respect to parametric uncertainty in the plant. The proposed approach to control design allows for both of these objectives to be handled within the framework of constrained optimization. The resulting controller achieves acceptable performance and robustness characteristics.

  11. Applicability of Long Duration Exposure Facility environmental effects data to the design of Space Station Freedom electrical power system

    NASA Technical Reports Server (NTRS)

    Christie, Robert J.; Lu, Cheng-Yi; Aronoff, Irene

    1992-01-01

    Data defining space environmental effects on the Long Duration Exposure Facility (LDEF) are examined in terms of the design of the electrical power system (EPS) of the Space Station Freedom (SSF). The significant effects of long-term exposure to space are identified with respect to the performance of the LDEF's materials, components, and systems. A total of 57 experiments were conducted on the LDEF yielding information regarding coatings, thermal systems, electronics, optics, and power systems. The resulting database is analyzed in terms of the specifications of the SSF EPS materials and subsystems and is found to be valuable in the design of control and protection features. Specific applications are listed for findings regarding the thermal environment, atomic oxygen, UV and ionizing radiation, debris, and contamination. The LDEF data are shown to have a considerable number of applications to the design and planning of the SSF and its EPS.

  12. Development and Optimized Design of Propeller Pump System & Structure with VFD in Low-head Pumping Station

    NASA Astrophysics Data System (ADS)

    Rentian, Zhang; Honggeng, Zhu; Arnold, Jaap; Linbi, Yao

    2010-06-01

    Compared with vertical-installed pumps, the propeller (bulb tubular) pump systems can achieve higher hydraulic efficiencies, which are particularly suitable for low-head pumping stations. More than four propeller pumping stations are being, or will be built in the first stage of the S-to-N Water Diversion Project in China, diverting water from Yangtze River to the northern part of China to alleviate water-shortage problems and develop the economy. New structures of propeller pump have been developed for specified pumping stations in Jiangsu and Shandong Provinces respectively and Variable Frequency Drives (VFDs) are used in those pumping stations to regulate operating conditions. Based on the Navier-Stokes equations and the standard k-e turbulent model, numerical simulations of the flow field and performance prediction in the propeller pump system were conducted on the platform of commercial software CFX by using the SIMPLEC algorithm. Through optimal design of bulb dimensions and diffuser channel shape, the hydraulic system efficiency has improved evidently. Furthermore, the structures of propeller pumps have been optimized to for the introduction of conventional as well as permanent magnet motors. In order to improve the hydraulic efficiency of pumping systems, both the pump discharge and the motor diameter were optimized respectively. If a conventional motor is used, the diameter of the pump casing has to be increased to accommodate the motor installed inside. If using a permanent magnet motor, the diameter of motor casing can be decreased effectively without decreasing its output power, thus the cross-sectional area is enlarged and the velocity of flowing water decreased favorably to reduce hydraulic loss of discharge channel and thereby raising the pumping system efficiency. Witness model tests were conducted after numerical optimization on specific propeller pump systems, indicating that the model system hydraulic efficiencies can be improved by 0.5%˜3.7% in

  13. A design for an intelligent monitor and controller for space station electrical power using parallel distributed problem solving

    NASA Technical Reports Server (NTRS)

    Morris, Robert A.

    1990-01-01

    The emphasis is on defining a set of communicating processes for intelligent spacecraft secondary power distribution and control. The computer hardware and software implementation platform for this work is that of the ADEPTS project at the Johnson Space Center (JSC). The electrical power system design which was used as the basis for this research is that of Space Station Freedom, although the functionality of the processes defined here generalize to any permanent manned space power control application. First, the Space Station Electrical Power Subsystem (EPS) hardware to be monitored is described, followed by a set of scenarios describing typical monitor and control activity. Then, the parallel distributed problem solving approach to knowledge engineering is introduced. There follows a two-step presentation of the intelligent software design for secondary power control. The first step decomposes the problem of monitoring and control into three primary functions. Each of the primary functions is described in detail. Suggestions for refinements and embelishments in design specifications are given.

  14. Conceptual Design of the Adaptive Optics System for the Laser Communication Relay Demonstration Ground Station at Table Mountain

    NASA Technical Reports Server (NTRS)

    Roberts, Lewis C., Jr.; Page, Norman A.; Burruss, Rick S.; Truong, Tuan N.; Dew, Sharon; Troy, Mitchell

    2013-01-01

    The Laser Communication Relay Demonstration will feature a geostationary satellite communicating via optical links to multiple ground stations. The first ground station (GS-1) is the 1m OCTL telescope at Table Mountain in California. The optical link will utilize pulse position modulation (PPM) and differential phase shift keying (DPSK) protocols. The DPSK link necessitates that adaptive optics (AO) be used to relay the incoming beam into the single mode fiber that is the input of the modem. The GS-1 AO system will have two MEMS Deformable mirrors to achieve the needed actuator density and stroke limit. The AO system will sense the aberrations with a Shack-Hartmann wavefront sensor using the light from the communication link's 1.55 microns laser to close the loop. The system will operate day and night. The system's software will be based on heritage software from the Palm 3000 AO system, reducing risk and cost. The AO system is being designed to work at r(sub 0) greater than 3.3 cm (measured at 500 nm and zenith) and at elevations greater than 20deg above the horizon. In our worst case operating conditions we expect to achieve Strehl ratios of over 70% (at 1.55 microns), which should couple 57% of the light into the single mode DPSK fiber. This paper describes the conceptual design of the AO system, predicted performance and discusses some of the trades that were conducted during the design process.

  15. Design of a monitor and simulation terminal (master) for space station telerobotics and telescience

    NASA Technical Reports Server (NTRS)

    Lopez, L.; Konkel, C.; Harmon, P.; King, S.

    1989-01-01

    Based on Space Station and planetary spacecraft communication time delays and bandwidth limitations, it will be necessary to develop an intelligent, general purpose ground monitor terminal capable of sophisticated data display and control of on-orbit facilities and remote spacecraft. The basic elements that make up a Monitor and Simulation Terminal (MASTER) include computer overlay video, data compression, forward simulation, mission resource optimization and high level robotic control. Hardware and software elements of a MASTER are being assembled for testbed use. Applications of Neural Networks (NNs) to some key functions of a MASTER are also discussed. These functions are overlay graphics adjustment, object correlation and kinematic-dynamic characterization of the manipulator.

  16. Power converter

    NASA Technical Reports Server (NTRS)

    Black, J. M. (Inventor)

    1981-01-01

    A dc-to-dc converter employs four transistor switches in a bridge to chop dc power from a source, and a voltage multiplying diode rectifying ladder network to rectify and filter the chopped dc power for delivery to a load. The bridge switches are cross coupled in order for diagonally opposite pairs to turn on and off together using RC networks for the cross coupling to achieve the mode of operation of a free running multivibrator, and the diode rectifying ladder is configured to operate in a push-pull mode driven from opposite sides of the multivibrator outputs of the ridge switches. The four transistor switches provide a square-wave output voltage which as a peak-to-peak amplitude that is twice the input dc voltage, and is thus useful as a dc-to-ac inverter.

  17. Proceedings of the Flat-Plate Solar Array Project Research Forum on the Design of Flat-Plate Photovoltaic Arrays for Central Stations

    NASA Technical Reports Server (NTRS)

    1983-01-01

    The Flat Plate Solar Array Project, focuses on advancing technologies relevant to the design and construction of megawatt level central station systems. Photovoltaic modules and arrays for flat plate central station or other large scale electric power production facilities require the establishment of a technical base that resolves design issues and results in practical and cost effective configurations. Design, qualification and maintenance issues related to central station arrays derived from the engineering and operating experiences of early applications and parallel laboratory reserch activities are investigated. Technical issues are examined from the viewpoint of the utility engineer, architect/engineer and laboratory researcher. Topics on optimum source circuit designs, module insulation design for high system voltages, array safety, structural interface design, measurements, and array operation and maintenance are discussed.

  18. Space station definitions, design, and development. Task 5: Multiple arm telerobot coordination and control: Manipulator design methodology

    NASA Technical Reports Server (NTRS)

    Stoughton, R. M.

    1990-01-01

    A proposed methodology applicable to the design of manipulator systems is described. The current design process is especially weak in the preliminary design phase, since there is no accepted measure to be used in trading off different options available for the various subsystems. The design process described uses Cartesian End-Effector Impedance as a measure of performance for the system. Having this measure of performance, it is shown how it may be used to determine the trade-offs necessary to the preliminary design phase. The design process involves three main parts: (1) determination of desired system performance in terms of End-Effector Impedance; (2) trade-off design options to achieve this desired performance; and (3) verification of system performance through laboratory testing. The design process is developed using numerous examples and experiments to demonstrate the feasability of this approach to manipulator design.

  19. Spallation neutron source target station issues

    SciTech Connect

    Gabriel, T.A.; Barnes, J.N.; Charlton, L.A.

    1996-10-01

    In many areas of physics, materials and nuclear engineering, it is extremely valuable to have a very intense source of neutrons so that the structure and function of materials can be studied. One facility proposed for this purpose is the National Spallation Neutron Source (NSNS). This facility will consist of two parts: (1) a high-energy ({approximately}1 GeV) and high powered ({approximately} 1 MW) proton accelerator, and (2) a target station which converts the protons to low-energy ({le} 2 eV) neutrons and delivers them to the neutron scattering instruments. This paper deals with the second part, i.e., the design and development of the NSNS target station and the scientifically challenging issues. Many scientific and technical disciplines are required to produce a successful target station. These include engineering, remote handling, neutronics, materials, thermal hydraulics, and instrumentation. Some of these areas will be discussed.

  20. Design and economics of a plant to convert western subbituminous coal to pipeline gas using dry-feed, entrained flow gasifiers. Topical report, January 1987-May 1987

    SciTech Connect

    Sandler, H.S.; Smelser, S.C.

    1987-05-01

    A first-pass design and cost estimate was prepared for a plant to convert western subbituminous coal to pipeline gas using dry-feed, entrained-flow (Shell-type) gasifiers with GRI's fixed-bed direct-methanation process. Results indicate that this plant could produce pipeline gas at a cost competitive with the Lurgi process using lignite coal, and slightly more expensive than gas produced from the KRW process. The plant design's overall thermal efficiency is lower than that of the KRW Wyodak or the Lurgi Lignite designs. The levelized constant-dollar cost of gas for the 125 billion Btu/day dry-feed, entrained-flow plant is estimated at $5.17/MMBtu.

  1. Turbo-Brayton Power Converter

    NASA Technical Reports Server (NTRS)

    Breedlove, Jeffrey

    2015-01-01

    Future NASA space missions will require advanced thermal-to-electric power converters that are reliable, efficient, and lightweight. Creare, LLC, is developing a turbo-Brayton power converter that offers high efficiency and specific power. The converter employs gas bearings to provide maintenance free, long-life operation. Discrete components can be packaged to fit optimally with other subsystems, and the converter's continuous gas flow can communicate directly with remote heat sources and heat rejection surfaces without the need for ancillary heat-transfer components and intermediate flow loops. Creare has completed detailed analyses, trade studies, fabrication trials, and preliminary designs for the components and converter assembly. The company is fabricating and testing a breadboard converter.

  2. Radio spectrum surveillance station

    NASA Technical Reports Server (NTRS)

    Hersey, D. R.

    1979-01-01

    The paper presents a general and functional description of a low-cost surveillance station designed as the first phase of NASA's program to develop a radio spectrum surveillance capability for deep space stations for identifying radio frequency interference sources. The station described has identified several particular interferences and is yielding spectral signature data which, after cataloging, will serve as a library for rapid identification of frequently observed interference. Findings from the use of the station are discussed.

  3. Exploration-Related Research on the International Space Station: Connecting Science Results to the Design of Future Missions

    NASA Technical Reports Server (NTRS)

    Rhatigan, Jennifer L.; Robinson, Julie A.; Sawin, Charles F.; Ahlf, Peter R.

    2005-01-01

    In January, 2004, the US President announced a vision for space exploration, and charged NASA with utilizing the International Space Station (ISS) for research and technology targeted at supporting the US space exploration goals. This paper describes: 1) what we have learned from the first four years of research on ISS relative to the exploration mission, 2) the on-going research being conducted in this regard, 3) our current understanding of the major exploration mission risks that the ISS can be used to address, and 4) current progress in realigning NASA s research portfolio for ISS to support exploration missions. Specifically, we discuss the focus of research on solving the perplexing problems of maintaining human health on long-duration missions, and the development of countermeasures to protect humans from the space environment, enabling long duration exploration missions. The interchange between mission design and research needs is dynamic, where design decisions influence the type of research needed, and results of research influence design decisions. The fundamental challenge to science on ISS is completing experiments that answer key questions in time to shape design decisions for future exploration. In this context, exploration-relevant research must do more than be conceptually connected to design decisions-it must become a part of the mission design process.

  4. Designing for Reliability and Robustness in International Space Station Exercise Countermeasures Systems

    NASA Technical Reports Server (NTRS)

    Moore, Cherice; Svetlik, Randall; Williams, Antony

    2017-01-01

    As spaceflight durations have increased over the last four decades, the effects of microgravity on the human body have become far better understood, as have the exercise countermeasures. Through use of a combination of aerobic and resistive exercise devices, today's astronauts and cosmonauts are able to partially counter the losses in muscle strength, aerobic fitness, and bone strength that otherwise might occur during their missions on the International Space Station (ISS). Since 2000, the ISS has employed a variety of exercise equipment used as countermeasures to these risks. Providing reliable and available exercise systems has presented significant challenges due to the unique environment. In solving these, lessons have been learned that can inform development of future systems.

  5. Optimized concept design of the target station of Chinese spallation neutron source

    NASA Astrophysics Data System (ADS)

    Yan, Q. W.; Yin, W.; Yu, B. L.

    2005-08-01

    CSNS (Chinese spallation neutron source) target station, with proton beam power of 100 kW, consists of Tungsten rectangular target surrounded by a beryllium/steel reflector, three wing-moderators and the shield having 18 beam tubes. The leakage neutron intensity from the target (with reflector) and heat deposition on the target, reflector and shield were calculated using Monte Carlo code NMTC/JAM respectively. It is reported that the target having rectangular section will produce more leakage neutron intensity than a square one for the same proton power. The temperature and thermal stress distribution in the target disks were calculated by the finite element method. The performances of moderators were calculated using MCNP-4A code.

  6. Systems engineering aspects of a preliminary conceptual design of the space station environmental control and life support system

    NASA Technical Reports Server (NTRS)

    Lin, C. H.; Meyer, M. S.

    1983-01-01

    The systems engineering aspects of developing a conceptual design of the Space Station Environmental Control and Life Support System (ECLSS) are discussed. Topics covered include defining system requirements and groundrules for approach, formulating possible cycle closure options, and establishing a system-level mass balance on the essential materials processed in oxygen and water cycles. Consideration is also given to the performance of a system trade-off study to determine the best degree of cycle closure for the ECLSS, and the construction of a conceptual design of the ECLSS with subsystem performance specifications and candidate concepts. For the optimum balance between development costs, technological risks, and resupply penalties, a partially closed cycle ECLSS option is suggested.

  7. Design Development of a Combined Deployment and Pointing System for the International Space Station Neutron Star Interior Composition Explorer Telescope

    NASA Technical Reports Server (NTRS)

    Budinoff, Jason; Gendreau, Keith; Arzoumanian, Zaven; Baker, Charles; Berning, Robert; Colangelo, Todd; Holzinger, John; Lewis, Jesse; Liu, Alice; Mitchell, Alissa; Monroe, Chuck; Pugh, Richard; Willey, Roger

    2015-01-01

    This paper describes the design of a unique suite of mechanisms which make up the Deployment and Pointing System (DAPS) for the Neutron Star Interior Composition Explorer (NICER/SEXTANT) instrument, an X-Ray telescope, which will be mounted on the International Space Station (ISS). The DAPS system uses 4 stepper motor actuators to deploy the telescope box, latch it in the deployed position, and allow it to track sky targets. The DAPS gimbal architecture provides full-hemisphere coverage, and is fully re-stowable. The compact design of the mechanism allowed the majority of total instrument volume to be used for science. Override features allow DAPS to be stowed by ISS robotics.

  8. Design Development of a Combined Deployment and Pointing System for the International Space Station Neutron Star Interior Composition Explorer Telescope

    NASA Technical Reports Server (NTRS)

    Budinoff, Jason; Gendreau, Keith; Arzoumanian, Zaven; Baker, Charles; Berning, Robert; Colangelo, TOdd; Holzinger, John; Lewis, Jesse; Liu, Alice; Mitchell, Alissa; Monroe, Chuck; Pugh, Richard; Wiley, Roger

    2016-01-01

    This paper describes the design of a unique suite of mechanisms that make up the Deployment and Pointing System (DAPS) for the Neutron Star Interior Composition Explorer (NICER/SEXTANT) instrument, an X-Ray telescope, which will be mounted on the International Space Station (ISS). The DAPS system uses four stepper motor actuators to deploy the telescope box, latch it in the deployed position, and allow it to track sky targets. The DAPS gimbal architecture provides full-hemisphere coverage, and is fully re-stowable. The compact design of the mechanism allowed the majority of total instrument volume to be used for science. Override features allow DAPS to be stowed by ISS robotics.

  9. Thermionic converter

    DOEpatents

    Rasor, Ned S.; Britt, Edward J.

    1976-01-01

    A gas-filled thermionic converter is provided with a collector and an emitter having a main emitter region and an auxiliary emitter region in electrical contact with the main emitter region. The main emitter region is so positioned with respect to the collector that a main gap is formed therebetween and the auxiliary emitter region is so positioned with respect to the collector that an auxiliary gap is formed therebetween partially separated from the main gap with access allowed between the gaps to allow ionizable gas in each gap to migrate therebetween. With heat applied to the emitter the work function of the auxiliary emitter region is sufficiently greater than the work function of the collector so that an ignited discharge occurs in the auxiliary gap and the work function of the main emitter region is so related to the work function of the collector that an unignited discharge occurs in the main gap sustained by the ions generated in the auxiliary gap. A current flows through a load coupled across the emitter and collector due to the unignited discharge in the main gap.

  10. Design of a remotely piloted vehicle for a low Reynolds number station keeping mission

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Six teams of senior level Aerospace Engineering undergraduates were given a request for proposal, asking for a design concept for a remotely piloted vehicle (RPV). This RPV was to be designed to fly at a target Reynolds number of 1 times 10(exp 5). The craft was to maximize loiter time and perform an indoor, closed course flight. As part of the proposal, each team was required to construct a prototype and validate their design with a flight demonstration.

  11. Conceptual design of A 50 MW central station photovoltaic power plant

    NASA Astrophysics Data System (ADS)

    Stranix, A. J.; Firester, A. H.

    1983-09-01

    The conceptual design of a 50 MW photovoltaic powerplant based on thin film amorphous silicon panels is presented, in a context of installation, operation and maintenance at a site in central New Jersey which allows the evaluation of performance on the basis of actual insolation data. The design criterion employed minimizes the installed plant cost/annual kW-hr of electricity generated. The cost performance values obtained are compared with a value analysis conducted for the present design in conjunction with the utility company operating in the region of the study.

  12. Design studies and commissioning plans for plasma acceleration research station experimental program

    SciTech Connect

    Mete, O.; Xia, G.; Hanahoe, K.; Dover, M.; Wigram, M.; Wright, J.; Zhang, J.; Smith, J.

    2015-10-15

    Plasma acceleration research station is an electron beam driven plasma wakefield acceleration test stand proposed for CLARA facility in Daresbury Laboratory. In this paper, the interaction between the electron beam and the plasma is numerically characterised via 2D numerical studies by using VSIM code. The wakefields induced by a single bunch travelling through the plasma were found to vary from 200 MV/m to 3 GV/m for a range of bunch length, bunch radius, and plasma densities. Energy gain for the particles populating the bunch tail through the wakefields driven by the head of the bunch was demonstrated. After determining the achievable field for various beams and plasma configurations, a reference setting was determined for further studies. Considering this reference setting, the beam quality studies were performed for a two-bunch acceleration case. The maximum energy gain as well as the energy spread mitigation by benefiting from the beam loading was investigated by positioning the witness and driver bunches with respect to each other. Emittance growth mechanisms were studied considering the beam-plasma and beam-wakefield interactions. Eventually, regarding the findings, the initial commissioning plans and the aims for the later stages were summarised.

  13. Space station system analysis study. Part 3: Documentation. Volume 2: Technical report. [structural design and construction

    NASA Technical Reports Server (NTRS)

    1977-01-01

    An analysis of construction operation is presented as well as power system sizing requirements. Mission hardware requirements are reviewed in detail. Space construction base and design configurations are also examined.

  14. Without Gravity: Designing Science Equipment for the International Space Station and Beyond

    NASA Technical Reports Server (NTRS)

    Sato, Kevin Y.

    2016-01-01

    This presentation discusses space biology research, the space flight factors needed to design hardware to conduct biological science in microgravity, and examples of NASA and commercial hardware that enable space biology study.

  15. An Ecological Approach to the Design of UAV Ground Control Station (GCS) Status Displays

    NASA Technical Reports Server (NTRS)

    Dowell, Susan; Morphew, Ephimia; Shively, Jay

    2003-01-01

    Use of UAVs in military and commercial applications will continue to increase. However, there has been limited research devoted to UAV GCS design. The current study employed an ecological approach to interfac e design. Ecological Interface Design (EID) can be characterized as r epresenting the properties of a system, such that an operator is enco uraged to use skill-based behavior when problem solving. When more ef fortful cognitive processes become necessary due to unfamiliar situations, the application of EID philosophy supports the application of kn owledge-based behavior. With advances toward multiple UAV command and control, operators need GCS interfaces designed to support understan ding of complex systems. We hypothesized that use of EID principles f or the display of UAV status information would result in better opera tor performance and situational awareness, while decreasing workload. Pilots flew a series of missions with three UAV GCS displays of statu s information (Alphanumeric, Ecological, and Hybrid display format). Measures of task performance, Situational Awareness, and workload dem onstrated the benefits of using an ecological approach to designing U AV GCS displays. The application of ecological principles to the design of UAV GCSs is a promising area for improving UAV operations.

  16. Design challenges of EO polymer based leaky waveguide deflector for 40 Gs/s all-optical analog-to-digital converters

    NASA Astrophysics Data System (ADS)

    Hadjloum, Massinissa; El Gibari, Mohammed; Li, Hongwu; Daryoush, Afshin S.

    2016-08-01

    Design challenges and performance optimization of an all-optical analog-to-digital converter (AOADC) is presented here. The paper addresses both microwave and optical design of a leaky waveguide optical deflector using electro-optic (E-O) polymer. The optical deflector converts magnitude variation of the applied RF voltage into variation of deflection angle out of a leaky waveguide optical beam using the linear E-O effect (Pockels effect) as part of the E-O polymer based optical waveguide. This variation of deflection angle as result of the applied RF signal is then quantized using optical windows followed by an array of high-speed photodetectors. We optimized the leakage coefficient of the leaky waveguide and its physical length to achieve the best trade-off between bandwidth and the deflected optical beam resolution, by improving the phase velocity matching between lightwave and microwave on one hand and using pre-emphasis technique to compensate for the RF signal attenuation on the other hand. In addition, for ease of access from both optical and RF perspective, a via-hole less broad bandwidth transition is designed between coplanar pads and coupled microstrip (CPW-CMS) driving electrodes. With the best reported E-O coefficient of 350 pm/V, the designed E-O deflector should allow an AOADC operating over 44 giga-samples-per-seconds with an estimated effective resolution of 6.5 bits on RF signals with Nyquist bandwidth of 22 GHz. The overall DC power consumption of all components used in this AOADC is of order of 4 W and is dominated by power consumption in the power amplifier to generate a 20 V RF voltage in 50 Ohm system. A higher sampling rate can be achieved at similar bits of resolution by interleaving a number of this elementary AOADC at the expense of a higher power consumption.

  17. Optical, mechanical, and electro-optical design of an interferometric test station for massive parallel inspection of MEMS and MOEMS

    NASA Astrophysics Data System (ADS)

    Gastinger, Kay; Haugholt, Karl Henrik; Kujawinska, Malgorzata; Jozwik, Michal; Schaeffel, Christoph; Beer, Stephan

    2009-06-01

    The paper presents the optical, mechanical, and electro-optical design of an interferometric inspection system for massive parallel inspection of MicroElectroMechanicalSystems (MEMS) and MicroOptoElectroMechanicalSystems (MOEMS). The basic idea is to adapt a micro-optical probing wafer to the M(O)EMS wafer under test. The probing wafer is exchangeable and contains a micro-optical interferometer array. A low coherent and a laser interferometer array are developed. Two preliminary interferometer designs are presented; a low coherent interferometer array based on a Mirau configuration and a laser interferometer array based on a Twyman-Green configuration. The optical design focuses on the illumination and imaging concept for the interferometer array. The mechanical design concentrates on the scanning system and the integration in a standard test station for micro-fabrication. Models of single channel low coherence and laser interferometers and preliminary measurement results are presented. The smart-pixel approach for massive parallel electro-optical detection and data reduction is discussed.

  18. Design and the parametric testing of the space station prototype integrated vapor compression distillation water recovery module

    NASA Technical Reports Server (NTRS)

    Reveley, W. F.; Nuccio, P. P.

    1975-01-01

    Potable water for the Space Station Prototype life support system is generated by the vapor compression technique of vacuum distillation. A description of a complete three-man modular vapor compression water renovation loop that was built and tested is presented; included are all of the pumps, tankage, chemical post-treatment, instrumentation, and controls necessary to make the loop representative of an automatic, self-monitoring, null gravity system. The design rationale is given and the evolved configuration is described. Presented next are the results of an extensive parametric test during which distilled water was generated from urine and urinal flush water with concentration of solids in the evaporating liquid increasing progressively to 60 percent. Water quality, quantity and production rate are shown together with measured energy consumption rate in terms of watt-hours per kilogram of distilled water produced.

  19. Composite rod insulators for ac power lines; Electrical performance of various designs at a coastal testing station

    SciTech Connect

    Houlgate, R.G.; Swift, D.A. )

    1990-10-01

    The electrical performance of thirty-six composite insulators - of four commercial types for each AC system level of 34.5 kV, 230 kV and 500 kV - has been determined at the CEGB insulator testing station, Brighton, England. The weathershed materials were epoxy-resin, ethylene propylene rubber and silicone rubber; half of the 230 kV insulators had no stress rings. Surface leakage current was recorded for surge levels of 25 mA, 150 mA and 500 mA; a special technique was developed to obtain the flashover statistics of the 500 kV insulators, thereby enabling performance of the composite insulator to be quantified relative to that of a string of cap and pin porcelain insulators of anti-fog design, the deterioration of the insulators was observed by making regular visual inspections. The practical consequences of the findings and the causes of the degradation are discussed.

  20. Proceedings of the Flat-Plate Solar Array Project Research Forum on the design of flat-plate photovoltaic arrays for central stations

    SciTech Connect

    1983-01-01

    The Flat-Plate Solar Array Project, managed by the Jet Propulsion Laboratory for the US Department of Energy, has focused on advancing technologies relevant to the design and construction of megawatt-level central-station systems. Photovoltaic modules and arrays for flat-plate central-station or other large-scale electric power production facilities require the establishment of a technical base that resolves design issues and results in practical and cost-effective configurations. The Central Station Research Forum addressed design, qualification and maintenance issues related to central-station arrays derived from the engineering and operating experiences of early applications and parallel laboratory research activities. Technical issues were examined from the viewpoint of the utility engineer, architect-engineer and laboratory researcher. The forum included presentations on optimum source-circuit designs, module insulation design for high system voltages, array safety, structural interface design, measurements and array operation and maintenance. The Research Forum focused on current capabilities as well as design difficulties requiring additional technological thrusts and/or continued research emphasis. Session topic summaries highlighting major points during group discussions, identifying promising technical approaches or areas of future research, are presented.

  1. Preliminary design and cost of a 1-megawatt solar-pumped iodide laser space-to-space transmission station

    NASA Technical Reports Server (NTRS)

    Deyoung, R. J.; Walker, G. H.; Williams, M. D.; Schuster, G. L.; Conway, E. J.

    1987-01-01

    A preliminary conceptual design of a space-based solar pumped iodide laser emitting 1 megawatt of laser power for space-to-space power transmission is described. A near parabolic solar collector focuses sunlight onto the t-C4F9I (perfluoro-t butyl iodide) lasant within a transverse flow optical cavity. Using waste heat, a thermal system was designed to supply compressor and auxiliary power. System components were designed with weight and cost estimates assigned. Although cost is very approximate, the cost comparison of individual system components leads to valuable insights for future research. In particular, it was found that laser efficiency was not a dominant cost or weight factor, the dominant factor being the laser cavity and laser transmission optics. The manufacturing cost was approx. two thirds of the total cost with transportation to orbit the remainder. The flowing nonrenewable lasant comprised 20% of the total life cycle cost of the system and thus was not a major cost factor. The station mass was 92,000 kg without lasant, requiring approx. four shuttle flights to low Earth orbit where an orbital transfer vehicle will transport it to the final altitude of 6378 km.

  2. Matters concerned with designing distributed systems for automated control of electrical equipment at power stations

    NASA Astrophysics Data System (ADS)

    Gorozhankin, P. A.; Krasnova, M. E.

    2011-10-01

    Matters concerned with developing the working designs of systems for automated control of electrical equipment are discussed. Basic technical requirements for computerized automation facilities are formulated from the viewpoint of ensuring the required scope of functions and fault tolerance, and proposals for the layout and placement of these facilities are suggested. A special section devoted to protection of automated process control systems from computer viruses is given.

  3. The results of a limited study of approaches to the design, fabrication, and testing of a dynamic model of the NASA IOC space station. Executive summary

    NASA Technical Reports Server (NTRS)

    Brooks, George W.

    1985-01-01

    The options for the design, construction, and testing of a dynamic model of the space station were evaluated. Since the definition of the space station structure is still evolving, the Initial Operating Capacity (IOC) reference configuration was used as the general guideline. The results of the studies treat: general considerations of the need for and use of a dynamic model; factors which deal with the model design and construction; and a proposed system for supporting the dynamic model in the planned Large Spacecraft Laboratory.

  4. Mars Micro-Meteorology Station Electronic Design, Assembly and Test Project

    NASA Technical Reports Server (NTRS)

    Twiggs, Robert J.; Merrihew, Seven; Engberg, Brian; Hicks, Michael; Tillier, Clemens

    1996-01-01

    The Micro-Met mission is a micro-meteorological experiment for Mars designed to take globally distributed pressure measurements for at least one martian year. A series of 16 landers equally spaced over the planet's surface will take pressure and temperature data and relay it to investigators on Earth. Measurements will be logged once every hour and transmitted to an orbiter once every thirty days using Mars Balloon Relay protocol. Micro-Met data will aid tremendously in the development and refinement of a global model of Martian weather.

  5. Solid radioactive waste management facility design for managing CANDU{sup R} 600 MW nuclear generating station re-tube/refurbishment Waste Streams

    SciTech Connect

    Pontikakis, N.; Hopkins, J.; Scott, D.; Bajaj, V.; Nosella, L.

    2007-07-01

    The main design features of the re-tube canisters, waste handling equipment and waste containers designed by Atomic Energy of Canada Limited (AECL{sup R}) and implemented in support of the re-tube/refurbishment activities for Candu 600 MW nuclear generating stations are described in this paper. The re-tube/refurbishment waste characterization and the waste management principles, which form the basis of the design activities, are also briefly outlined. (authors)

  6. Control of space stations

    NASA Technical Reports Server (NTRS)

    Lee, K. Y.

    1983-01-01

    A study is made to develop controllers for the NASA-JSC Triangular Space Station and evaluate their performances to make recommendations for structural design and/or control alternatives. The control system design assumes the rigid body of the Space Station and developes the lumped parameter control system by using the Inverse Optimal Control Theory. In order to evaluate the performance of the control system, a Parameter Estimation algorithm is being developed which will be used in modeling an equivalent but simpler Space Station model. Finally, a scaled version of the Space Station is being built for the purpose of physical experiments to evaluate the control system performance.

  7. Space station definition and preliminary design, WP-01. Volume 2: Results

    NASA Technical Reports Server (NTRS)

    Lenda, J. A.

    1987-01-01

    The basis for the studies and analyses which led to the results and conclusions documented and summarized, was the Engineering Master Schedule (EMS) generated by NASA and used as the controlling set of milestones and associated activities required to produce in a timely manner those products needed by all program participants in the establishment of an approved program baseline. The EMS consisted of twenty themes grouped into categories covering requirements, configurations, and strategies. A number of studies and analyses that were coordinated with the MSFC program and technical personnel as being needed to provide the requisite back-up material to satify the EMS were identified. These studies and analyses provided the data sufficient to support the conclusions and recommendations given to the MSFC in response to their EMS activity and to support the system level and conceptual design level approaches developed and reflected in the detailed sections of this document.

  8. Overview of Microbiological Tests Performed During the Design of the International Space Station Environmental Control and Life Support Systems

    NASA Technical Reports Server (NTRS)

    Roman, Monsi C.; Mittelman, Marc W.

    2010-01-01

    The design and manufacturing of the main Environmental Control and Life Support Systems (ECLSS) for the United States segments of the International Space Station (ISS) was an involved process that started in the late 1980's, with the assessment and testing of competing technologies that could be used to clean the air and recycle water. It culminated in 2009 with the delivery and successful activation of the Water Recovery System (WRS) water processor (WP). The ECLSS required the work of a team of engineers and scientist working together to develop systems that could clean and/or recycle human metabolic loads to maintain a clean atmosphere and provide the crew clean water. One of the main goals of the ECLSS is to minimize the time spent by the crew worrying about vital resources not available in the vacuum of space, which allows them to spend most of their time learning to live in a microgravity environment many miles from the comforts of Earth and working on science experiments. Microorganisms are a significant part of the human body as well as part of the environment that we live in. Therefore, the ISS ECLSS design had to take into account the effect microorganisms have on the quality of stored water and wastewater, as well as that of the air systems. Hardware performance issues impacted by the accumulation of biofilm and/or microbiologically influenced corrosion were also studied during the ECLSS development stages. Many of the tests that were performed had to take into account the unique aspects of a microgravity environment as well as the challenge of understanding how to design systems that could not be sterilized or maintained in a sterile state. This paper will summarize the work of several studies that were performed to assess the impacts and/or to minimize the effects of microorganisms in the design of a closed loop life support system.

  9. Design and Fabrication of a Differential Electrostatic Accelerometer for Space-Station Testing of the Equivalence Principle.

    PubMed

    Han, Fengtian; Liu, Tianyi; Li, Linlin; Wu, Qiuping

    2016-08-10

    The differential electrostatic space accelerometer is an equivalence principle (EP) experiment instrument proposed to operate onboard China's space station in the 2020s. It is designed to compare the spin-spin interaction between two rotating extended bodies and the Earth to a precision of 10(-12), which is five orders of magnitude better than terrestrial experiment results to date. To achieve the targeted test accuracy, the sensitive space accelerometer will use the very soft space environment provided by a quasi-drag-free floating capsule and long-time observation of the free-fall mass motion for integration of the measurements over 20 orbits. In this work, we describe the design and capability of the differential accelerometer to test weak space acceleration. Modeling and simulation results of the electrostatic suspension and electrostatic motor are presented based on attainable space microgravity condition. Noise evaluation shows that the electrostatic actuation and residual non-gravitational acceleration are two major noise sources. The evaluated differential acceleration noise is 1.01 × 10(-9) m/s²/Hz(1/2) at the NEP signal frequency of 0.182 mHz, by neglecting small acceleration disturbances. The preliminary work on development of the first instrument prototype is introduced for on-ground technological assessments. This development has already confirmed several crucial fabrication processes and measurement techniques and it will open the way to the construction of the final differential space accelerometer.

  10. Design and Manufacturing Considerations for Shockproof and Corrosion-Immune Superelastic Nickel-Titanium Bearings for a Space Station Application

    NASA Technical Reports Server (NTRS)

    DellaCorte, Christopher; Wozniak, Walter A.

    2012-01-01

    An intermetallic nickel-titanium alloy, 60NiTi (60wt%Ni, 40wt%Ti), is a promising tribological material for space mechanisms. 60NiTi offers a broad combination of physical properties that make it unique among bearing materials. 60NiTi is hard, electrically conductive, highly corrosion resistant, readily machined prior to final heat treatment, easily lubricated and is non-magnetic. It also falls within the class of superelastic alloys and can elastically endure large strains (beyond 5 percent) making it highly resistant to excessive and unexpected (shock) loads. Key material properties and characteristics such as elastic modulus, tensile fracture sensitivity and residual stress behavior, however, differ from conventional alloys such as steel and this significantly affects bearing design and manufacturing. In this paper, the preliminary design and manufacture of ball bearings made from 60NiTi are considered for a highly corrosive, lightly loaded, low speed bearing application found inside the International Space Station s water recycling system. The information presented is expected to help guide more widespread commercialization of this new technology into space mechanism and other applications.

  11. Design and Fabrication of a Differential Electrostatic Accelerometer for Space-Station Testing of the Equivalence Principle

    PubMed Central

    Han, Fengtian; Liu, Tianyi; Li, Linlin; Wu, Qiuping

    2016-01-01

    The differential electrostatic space accelerometer is an equivalence principle (EP) experiment instrument proposed to operate onboard China’s space station in the 2020s. It is designed to compare the spin-spin interaction between two rotating extended bodies and the Earth to a precision of 10−12, which is five orders of magnitude better than terrestrial experiment results to date. To achieve the targeted test accuracy, the sensitive space accelerometer will use the very soft space environment provided by a quasi-drag-free floating capsule and long-time observation of the free-fall mass motion for integration of the measurements over 20 orbits. In this work, we describe the design and capability of the differential accelerometer to test weak space acceleration. Modeling and simulation results of the electrostatic suspension and electrostatic motor are presented based on attainable space microgravity condition. Noise evaluation shows that the electrostatic actuation and residual non-gravitational acceleration are two major noise sources. The evaluated differential acceleration noise is 1.01 × 10−9 m/s2/Hz1/2 at the NEP signal frequency of 0.182 mHz, by neglecting small acceleration disturbances. The preliminary work on development of the first instrument prototype is introduced for on-ground technological assessments. This development has already confirmed several crucial fabrication processes and measurement techniques and it will open the way to the construction of the final differential space accelerometer. PMID:27517927

  12. Architectural Exploration and Design of Time-Interleaved SAR Arrays for Low-Power and High Speed A/D Converters

    NASA Astrophysics Data System (ADS)

    Saponara, Sergio; Nuzzo, Pierluigi; Nani, Claudio; van der Plas, Geert; Fanucci, Luca

    Time-interleaved (TI) analog-to-digital converters (ADCs) are frequently advocated as a power-efficient solution to realize the high sampling rates required in single-chip transceivers for the emerging communication schemes: ultra-wideband, fast serial links, cognitive-radio and software-defined radio. However, the combined effects of multiple distortion sources due to channel mismatches (bandwidth, offset, gain and timing) severely affect system performance and power consumption of a TI ADC and need to be accounted for since the earlier design phases. In this paper, system-level design of TI ADCs is addressed through a platform-based methodology, enabling effective investigation of different speed/resolution scenarios as well as the impact of parallelism on accuracy, yield, sampling-rate, area and power consumption. Design space exploration of a TI successive approximation ADC is performed top-down via Monte Carlo simulations, by exploiting behavioral models built bottom-up after characterizing feasible implementations of the main building blocks in a 90-nm 1-V CMOS process. As a result, two implementations of the TI ADC are proposed that are capable to provide an outstanding figure-of-merit below 0.15pJ/conversion-step.

  13. Potential converter for laser-power beaming

    NASA Technical Reports Server (NTRS)

    Walker, Gilbert H.; Williams, Michael D.; Schuster, Gregory L.; Iles, Peter A.

    1991-01-01

    Future space missions, such as those associated with the Space Exploration Initiative (SEI), will require large amounts of power for operation of bases, rovers, and orbit transfer vehicles. One method for supplying this power is to beam power from a spaced based or Earth based laser power station to a receiver where laser photons can be converted to electricity. Previous research has described such laser power stations orbiting the Moon and beaming power to a receiver on the surface of the Moon by using arrays of diode lasers. Photovoltaic converters that can be efficiently used with these diode lasers are described.

  14. Space station common module thermal management: Design and construction of a test bed

    NASA Technical Reports Server (NTRS)

    Barile, R. G.

    1986-01-01

    In this project, a thermal test bed was designed, simulated, and planned for construction. The thermal system features interior and exterior thermal loads and interfacing with the central-radiator thermal bus. Components of the test bed include body mounted radiator loop with interface heat exchangers (600 Btu/hr); an internal loop with cabin air-conditioning and cold plates (3400 Btu/hr); interface heat exchangers to the central bus (13,000 Btu/hr); and provisions for new technology including advanced radiators, thermal storage, and refrigeration. The apparatus will be mounted in a chamber, heated with lamps, and tested in a vacuum chamber with LN2-cooled walls. Simulation of the test bed was accomplished using a DEC PRO 350 computer and the software package TK! olver. Key input variables were absorbed solar radiation and cold plate loads. The results indicate temperatures on the two loops will be nominal when the radiation and cold plate loads are in the range of 25% to 75% of peak loads. If all loads fall to zero, except the cabin air system which was fixed, the radiator fluid will drop below -100 F and may cause excessive pressure drop. If all loads reach 100%, the cabin air temperature could rise to 96 F.

  15. A single aromatic core mutation converts a designed “primitive” protein from halophile to mesophile folding

    PubMed Central

    Longo, Liam M; Tenorio, Connie A; Kumru, Ozan S; Middaugh, C Russell; Blaber, Michael

    2015-01-01

    The halophile environment has a number of compelling aspects with regard to the origin of structured polypeptides (i.e., proteogenesis) and, instead of a curious niche that living systems adapted into, the halophile environment is emerging as a candidate “cradle” for proteogenesis. In this viewpoint, a subsequent halophile-to-mesophile transition was a key step in early evolution. Several lines of evidence indicate that aromatic amino acids were a late addition to the codon table and not part of the original “prebiotic” set comprising the earliest polypeptides. We test the hypothesis that the availability of aromatic amino acids could facilitate a halophile-to-mesophile transition by hydrophobic core-packing enhancement. The effects of aromatic amino acid substitutions were evaluated in the core of a “primitive” designed protein enriched for the 10 prebiotic amino acids (A,D,E,G,I,L,P,S,T,V)—having an exclusively prebiotic core and requiring halophilic conditions for folding. The results indicate that a single aromatic amino acid substitution is capable of eliminating the requirement of halophile conditions for folding of a “primitive” polypeptide. Thus, the availability of aromatic amino acids could have facilitated a critical halophile-to-mesophile protein folding adaptation—identifying a selective advantage for the incorporation of aromatic amino acids into the codon table. PMID:25297559

  16. Space station power system

    NASA Technical Reports Server (NTRS)

    Baraona, Cosmo R.

    1987-01-01

    The major requirements and guidelines that affect the space station configuration and power system are explained. The evolution of the space station power system from the NASA program development-feasibility phase through the current preliminary design phase is described. Several early station concepts are described and linked to the present concept. Trade study selections of photovoltaic system technologies are described in detail. A summary of present solar dynamic and power management and distribution systems is also given.

  17. Human factors issues and approaches in the spatial layout of a space station control room, including the use of virtual reality as a design analysis tool

    NASA Technical Reports Server (NTRS)

    Hale, Joseph P., II

    1994-01-01

    Human Factors Engineering support was provided for the 30% design review of the late Space Station Freedom Payload Control Area (PCA). The PCA was to be the payload operations control room, analogous to the Spacelab Payload Operations Control Center (POCC). This effort began with a systematic collection and refinement of the relevant requirements driving the spatial layout of the consoles and PCA. This information was used as input for specialized human factors analytical tools and techniques in the design and design analysis activities. Design concepts and configuration options were developed and reviewed using sketches, 2-D Computer-Aided Design (CAD) drawings, and immersive Virtual Reality (VR) mockups.

  18. Theoretical study on the effect of the design of small (milli-Newton) thruster jets on molecular contamination for the space station

    NASA Technical Reports Server (NTRS)

    Riley, B. R.

    1986-01-01

    The self-induced molecular contamination around the space station could have adverse effects on space station components (for example solar panels) as well as scientific experiments that might be done on or near the space station. Aerospace engineers need to design a space station (SS) propulsion system that keeps the SS in a stable orbit and at the same time does not allow the propellant gases to interfere with the experiments of the user. One scenario that might accomplish the above requirements is to use an electrothermal propulsion system, resistojet, that will thrust continuously in the hundreds of milli-Newton range which will provide a constant altitude for the SS with a low g environment. As a first attempt to understand the contamination from such a propulsion system, a point source model was developed. The numerical results of the point source model are given. Number column densities for CO2 are presented as a function of direction of observation (line of sight), temperature of the exit gas, and mean exit velocity. All the results are for a constant exhaust rate of 5,000 kg/year. In addition, a mathematical model to study the effect of nozzle design on the induced molecular environment around the space station produced by simple gas propellants is described. The mathematical model would allow one to follow the expansion of the gas from the throat of a nozzle to the nozzle exit plane and then into the space external to the nozzle.

  19. Equipment concept design and development plans for microgravity science and applications research on space station: Combustion tunnel, laser diagnostic system, advanced modular furnace, integrated electronics laboratory

    NASA Technical Reports Server (NTRS)

    Uhran, M. L.; Youngblood, W. W.; Georgekutty, T.; Fiske, M. R.; Wear, W. O.

    1986-01-01

    Taking advantage of the microgravity environment of space NASA has initiated the preliminary design of a permanently manned space station that will support technological advances in process science and stimulate the development of new and improved materials having applications across the commercial spectrum. Previous studies have been performed to define from the researcher's perspective, the requirements for laboratory equipment to accommodate microgravity experiments on the space station. Functional requirements for the identified experimental apparatus and support equipment were determined. From these hardware requirements, several items were selected for concept designs and subsequent formulation of development plans. This report documents the concept designs and development plans for two items of experiment apparatus - the Combustion Tunnel and the Advanced Modular Furnace, and two items of support equipment the Laser Diagnostic System and the Integrated Electronics Laboratory. For each concept design, key technology developments were identified that are required to enable or enhance the development of the respective hardware.

  20. Operation of high power converters in parallel

    NASA Technical Reports Server (NTRS)

    Decker, D. K.; Inouye, L. Y.

    1993-01-01

    High power converters that are used in space power subsystems are limited in power handling capability due to component and thermal limitations. For applications, such as Space Station Freedom, where multi-kilowatts of power must be delivered to user loads, parallel operation of converters becomes an attractive option when considering overall power subsystem topologies. TRW developed three different unequal power sharing approaches for parallel operation of converters. These approaches, known as droop, master-slave, and proportional adjustment, are discussed and test results are presented.

  1. Hardware-Algorithms Co-Design and Implementation of an Analog-to-Information Converter for Biosignals Based on Compressed Sensing.

    PubMed

    Pareschi, Fabio; Albertini, Pierluigi; Frattini, Giovanni; Mangia, Mauro; Rovatti, Riccardo; Setti, Gianluca

    2016-02-01

    We report the design and implementation of an Analog-to-Information Converter (AIC) based on Compressed Sensing (CS). The system is realized in a CMOS 180 nm technology and targets the acquisition of bio-signals with Nyquist frequency up to 100 kHz. To maximize performance and reduce hardware complexity, we co-design hardware together with acquisition and reconstruction algorithms. The resulting AIC outperforms previously proposed solutions mainly thanks to two key features. First, we adopt a novel method to deal with saturations in the computation of CS measurements. This allows no loss in performance even when 60% of measurements saturate. Second, the system is able to adapt itself to the energy distribution of the input by exploiting the so-called rakeness to maximize the amount of information contained in the measurements. With this approach, the 16 measurement channels integrated into a single device are expected to allow the acquisition and the correct reconstruction of most biomedical signals. As a case study, measurements on real electrocardiograms (ECGs) and electromyograms (EMGs) show signals that these can be reconstructed without any noticeable degradation with a compression rate, respectively, of 8 and 10.

  2. Design of single-winding energy-storage reactors for dc-to-dc converters using air-gapped magnetic-core structures

    NASA Technical Reports Server (NTRS)

    Ohri, A. K.; Wilson, T. G.; Owen, H. A., Jr.

    1977-01-01

    A procedure is presented for designing air-gapped energy-storage reactors for nine different dc-to-dc converters resulting from combinations of three single-winding power stages for voltage stepup, current stepup and voltage stepup/current stepup and three controllers with control laws that impose constant-frequency, constant transistor on-time and constant transistor off-time operation. The analysis, based on the energy-transfer requirement of the reactor, leads to a simple relationship for the required minimum volume of the air gap. Determination of this minimum air gap volume then permits the selection of either an air gap or a cross-sectional core area. Having picked one parameter, the minimum value of the other immediately leads to selection of the physical magnetic structure. Other analytically derived equations are used to obtain values for the required turns, the inductance, and the maximum rms winding current. The design procedure is applicable to a wide range of magnetic material characteristics and physical configurations for the air-gapped magnetic structure.

  3. Space Station fluid resupply

    NASA Astrophysics Data System (ADS)

    Winters, Al

    Viewgraphs on space station fluid resupply are presented. Space Station Freedom is resupplied with supercritical O2 and N2 for the ECLSS and USL on a 180 day resupply cycle. Resupply fluids are stored in the subcarriers on station between resupply cycles and transferred to the users as required. ECLSS contingency fluids (O2 and N2) are supplied and stored on station in a gaseous state. Efficiency and flexibility are major design considerations. Subcarrier approach allows multiple manifest combinations. Growth is achieved by adding modular subcarriers.

  4. Life-Prediction Parameters of Sapphire Determined for the Design of a Space Station Combustion Facility Window

    NASA Technical Reports Server (NTRS)

    Salem, Jonathan A.

    2003-01-01

    To characterize the stress corrosion parameters and predict the life of a sapphire window being considered for use in the International Space Station's Fluids and Combustion Facility, researchers at the NASA Glenn Research Center conducted stress corrosion tests, fracture toughness tests, and reliability analyses, as shown in the figures. Standardized test methods, developed and updated by the author under the auspices of American Society for Testing and Materials, were employed. One interesting finding is that sapphire exhibits a susceptibility to stress corrosion in water similar to that of glass. In addition to generating the stress corrosion parameters and fracture toughness data, closed-form expressions for the variances of the crack growth parameters were derived. The expressions allow confidence bands to be easily placed on life predictions of ceramic components. Brittle materials such as sapphire and quartz are required for windows in a variety of applications such as the Fluids and Combustion Facility. To minimize the launch weight of such facilities, researchers must design the windows to be as lightweight as possible. The safe use of lightweight, brittle windows in structural applications is limited by two factors: low fracture toughness and slow crack growth, or stress corrosion. Stress corrosion of these and other optical materials can occur in relatively common environments, such as humid air. Access to the data has been requested by designers for use in the life prediction of a Northrop Grumman F16 instrument window and a Jet Propulsion Laboratory instrument window. One Space Act Agreement has been formed. Future work includes the measurement of the life of subscale windows.

  5. Automating existing stations

    SciTech Connect

    Little, J.E.

    1986-09-01

    The task was to automate 20 major compressor stations along ANR Pipeline Co.'s Southeastern and Southwestern pipelines in as many months. Meeting this schedule required standardized hardware and software design. Working with Bristol Babcock Co., ANR came up with an off-the-shelf station automation package suitable for a variety of compressor stations. The project involved 148 engines with 488,880-hp in the 20 stations. ANR Pipeline developed software for these engines and compressors, including horsepower prediction and efficiency. The system places processors ''intelligence'' at each station and engine to monitor and control operations. The station processor receives commands from the company's gas dispatch center at Detroit and informs dispatchers of alarms, conditions, and decision it makes. The automation system is controlled by the Detroit center through a central communications network. Operating orders from the center are sent to the station processor, which obeys orders using the most efficient means of operation at the station's disposal. In a malfunction, a control and communications backup system takes over. Commands and information are directly transmitted between the center and the individual compressor stations. Stations receive their orders based on throughput, with suction and discharge pressure overrides. Additionally, a discharge temperature override protects pipeline coatings.

  6. Thermoelectric converters for alternating current standards

    NASA Astrophysics Data System (ADS)

    Anatychuk, L. I.; Taschuk, D. D.

    2012-06-01

    Thermoelectric converters of alternating current remain priority instruments when creating standard equipment. This work presents the results of design and manufacture of alternating current converter for a military standard of alternating current in Ukraine. Results of simulation of temperature distribution in converter elements, ways of optimization to improve the accuracy of alternating current signal reproduction are presented. Results of metrological trials are given. The quality of thermoelectric material specially created for alternating current metrology is verified. The converter was used in alternating current standard for the frequency range from 10 Hz to 30 MHz. The efficiency of using thermoelectric signal converters in measuring instruments is confirmed.

  7. Step-by-Step Design of an FPGA-Based Digital Compensator for DC/DC Converters Oriented to an Introductory Course

    ERIC Educational Resources Information Center

    Zumel, P.; Fernandez, C.; Sanz, M.; Lazaro, A.; Barrado, A.

    2011-01-01

    In this paper, a short introductory course to introduce field-programmable gate array (FPGA)-based digital control of dc/dc switching power converters is presented. Digital control based on specific hardware has been at the leading edge of low-medium power dc/dc switching converters in recent years. Besides industry's interest in this topic, from…

  8. Nonlinear control of voltage source converters in AC-DC power system.

    PubMed

    Dash, P K; Nayak, N

    2014-07-01

    This paper presents the design of a robust nonlinear controller for a parallel AC-DC power system using a Lyapunov function-based sliding mode control (LYPSMC) strategy. The inputs for the proposed control scheme are the DC voltage and reactive power errors at the converter station and the active and reactive power errors at the inverter station of the voltage-source converter-based high voltage direct current transmission (VSC-HVDC) link. The stability and robust tracking of the system parameters are ensured by applying the Lyapunov direct method. Also the gains of the sliding mode control (SMC) are made adaptive using the stability conditions of the Lyapunov function. The proposed control strategy offers invariant stability to a class of systems having modeling uncertainties due to parameter changes and exogenous inputs. Comprehensive computer simulations are carried out to verify the proposed control scheme under several system disturbances like changes in short-circuit ratio, converter parametric changes, and faults on the converter and inverter buses for single generating system connected to the power grid in a single machine infinite-bus AC-DC network and also for a 3-machine two-area power system. Furthermore, a second order super twisting sliding mode control scheme has been presented in this paper that provides a higher degree of nonlinearity than the LYPSMC and damps faster the converter and inverter voltage and power oscillations.

  9. Design of a reusable kinetic energy absorber for an astronaut safety tether to be used during extravehicular activities on the Space Station

    NASA Technical Reports Server (NTRS)

    Borthwick, Dawn E.; Cronch, Daniel F.; Nixon, Glen R.

    1991-01-01

    The goal of this project is to design a reusable safety device for a waist tether which will absorb the kinetic energy of an astronaut drifting away from the Space Station. The safety device must limit the tension of the tether line in order to prevent damage to the astronaut's space suit or to the structure of the spacecraft. The tether currently used on shuttle missions must be replaced after the safety feature has been developed. A reusable tether for the Space Station would eliminate the need for replacement tethers, conserving space and mass. This report presents background information, scope and limitations, methods of research and development, alternative designs, a final design solution and its evaluation, and recommendations for further work.

  10. Cycloidal Wave Energy Converter

    SciTech Connect

    Stefan G. Siegel, Ph.D.

    2012-11-30

    This program allowed further advancing the development of a novel type of wave energy converter, a Cycloidal Wave Energy Converter or CycWEC. A CycWEC consists of one or more hydrofoils rotating around a central shaft, and operates fully submerged beneath the water surface. It operates under feedback control sensing the incoming waves, and converts wave power to shaft power directly without any intermediate power take off system. Previous research consisting of numerical simulations and two dimensional small 1:300 scale wave flume experiments had indicated wave cancellation efficiencies beyond 95%. The present work was centered on construction and testing of a 1:10 scale model and conducting two testing campaigns in a three dimensional wave basin. These experiments allowed for the first time for direct measurement of electrical power generated as well as the interaction of the CycWEC in a three dimensional environment. The Atargis team successfully conducted two testing campaigns at the Texas A&M Offshore Technology Research Center and was able to demonstrate electricity generation. In addition, three dimensional wave diffraction results show the ability to achieve wave focusing, thus increasing the amount of wave power that can be extracted beyond what was expected from earlier two dimensional investigations. Numerical results showed wave cancellation efficiencies for irregular waves to be on par with results for regular waves over a wide range of wave lengths. Using the results from previous simulations and experiments a full scale prototype was designed and its performance in a North Atlantic wave climate of average 30kW/m of wave crest was estimated. A full scale WEC with a blade span of 150m will deliver a design power of 5MW at an estimated levelized cost of energy (LCOE) in the range of 10-17 US cents per kWh. Based on the new results achieved in the 1:10 scale experiments these estimates appear conservative and the likely performance at full scale will

  11. Radiation-Tolerant DC-DC Converters

    NASA Technical Reports Server (NTRS)

    Skutt, Glenn; Sable, Dan; Leslie, Leonard; Graham, Shawn

    2012-01-01

    A document discusses power converters suitable for space use that meet the DSCC MIL-PRF-38534 Appendix G radiation hardness level P classification. A method for qualifying commercially produced electronic parts for DC-DC converters per the Defense Supply Center Columbus (DSCC) radiation hardened assurance requirements was developed. Development and compliance testing of standard hybrid converters suitable for space use were completed for missions with total dose radiation requirements of up to 30 kRad. This innovation provides the same overall performance as standard hybrid converters, but includes assurance of radiation- tolerant design through components and design compliance testing. This availability of design-certified radiation-tolerant converters can significantly reduce total cost and delivery time for power converters for space applications that fit the appropriate DSCC classification (30 kRad).

  12. Multiple Craft Stations.

    ERIC Educational Resources Information Center

    Johns, Mary Sue

    1980-01-01

    Described are three craft stations (claywork, papermaking, and stamp designing) for intermediate grade students, to correlate with their classroom study which focused on Ohio: its history, geography, cities, industries, products and famous natives. (KC)

  13. Design and Testing of a 2-Hour Oxygen Prebreathe Protocol for Space Walks from the International Space Station

    NASA Technical Reports Server (NTRS)

    Gernhardt, Michael L.; Conkin, J.; Foster, P. P.; Pilmanis, A. A.; Butler, B. D.; Beltran, E.; Fife, C. E.; Vann, R. D.; Gerth, W. A.; Loftin, K. C.; Paloski, William H. (Technical Monitor)

    2000-01-01

    To develop and test a 2-hour prebreathe protocol for performing extravehicular activities (EVAs) from the International Space Station (ISS). Combinations of adynamia (non-walking), prebreathe exercise, and space suit donning options (10.2 vs. 14.7 psi) were evaluated, against timeline and consumable contraints to develop an operational 2- hour prebreathe protocol. Prospective accept/reject criteria were defined for decompression sickness (DCS) and venous gas emboli (VGE) from analysis of historical DCS data, combined with risk management of DCS under ISS mission circumstances. Maximum operational DCS levels were defined based on protecting for EVA capability with two crew-members at 95% confidence, throughout ISS lifetime (within the constraints of NASA DCS disposition policy JPG 1800.3). The accept/reject limits were adjusted for greater safety based on analysis of related medical factors. Monte-Carlo simulation was performed to design a closed sequential, multi-center human trial. Protocols were tested with 4 different prebreathe exercises (Phases I-IV), prior to exposure to 4.3 psi for 4 hrs. Subject selection, Doppler monitoring for VGE, test termination criteria, and DCS definitions were standardized. Phase I: upper and lower body exercises using dual-cycle ergometry (75% VO2 max for 10 min). Phase II: ergometry plus 24 min of light exercise (simulating space-suit preparations). Phase III: same 24 min of light exercise but no ergometry, and Phase IV: 56 min of light exercise without ergometry. A prebreathe procedure was accepted if, at 95% confidence, the incidence of DCS was less than 15% (with no Type II DCS), and Grade IV VGE was less than 20%.

  14. Model based multivariable controller for large scale compression stations. Design and experimental validation on the LHC 18KW cryorefrigerator

    SciTech Connect

    Bonne, François; Bonnay, Patrick; Bradu, Benjamin

    2014-01-29

    In this paper, a multivariable model-based non-linear controller for Warm Compression Stations (WCS) is proposed. The strategy is to replace all the PID loops controlling the WCS with an optimally designed model-based multivariable loop. This new strategy leads to high stability and fast disturbance rejection such as those induced by a turbine or a compressor stop, a key-aspect in the case of large scale cryogenic refrigeration. The proposed control scheme can be used to have precise control of every pressure in normal operation or to stabilize and control the cryoplant under high variation of thermal loads (such as a pulsed heat load expected to take place in future fusion reactors such as those expected in the cryogenic cooling systems of the International Thermonuclear Experimental Reactor ITER or the Japan Torus-60 Super Advanced fusion experiment JT-60SA). The paper details how to set the WCS model up to synthesize the Linear Quadratic Optimal feedback gain and how to use it. After preliminary tuning at CEA-Grenoble on the 400W@1.8K helium test facility, the controller has been implemented on a Schneider PLC and fully tested first on the CERN's real-time simulator. Then, it was experimentally validated on a real CERN cryoplant. The efficiency of the solution is experimentally assessed using a reasonable operating scenario of start and stop of compressors and cryogenic turbines. This work is partially supported through the European Fusion Development Agreement (EFDA) Goal Oriented Training Program, task agreement WP10-GOT-GIRO.

  15. Model based multivariable controller for large scale compression stations. Design and experimental validation on the LHC 18KW cryorefrigerator

    NASA Astrophysics Data System (ADS)

    Bonne, François; Alamir, Mazen; Bonnay, Patrick; Bradu, Benjamin

    2014-01-01

    In this paper, a multivariable model-based non-linear controller for Warm Compression Stations (WCS) is proposed. The strategy is to replace all the PID loops controlling the WCS with an optimally designed model-based multivariable loop. This new strategy leads to high stability and fast disturbance rejection such as those induced by a turbine or a compressor stop, a key-aspect in the case of large scale cryogenic refrigeration. The proposed control scheme can be used to have precise control of every pressure in normal operation or to stabilize and control the cryoplant under high variation of thermal loads (such as a pulsed heat load expected to take place in future fusion reactors such as those expected in the cryogenic cooling systems of the International Thermonuclear Experimental Reactor ITER or the Japan Torus-60 Super Advanced fusion experiment JT-60SA). The paper details how to set the WCS model up to synthesize the Linear Quadratic Optimal feedback gain and how to use it. After preliminary tuning at CEA-Grenoble on the 400W@1.8K helium test facility, the controller has been implemented on a Schneider PLC and fully tested first on the CERN's real-time simulator. Then, it was experimentally validated on a real CERN cryoplant. The efficiency of the solution is experimentally assessed using a reasonable operating scenario of start and stop of compressors and cryogenic turbines. This work is partially supported through the European Fusion Development Agreement (EFDA) Goal Oriented Training Program, task agreement WP10-GOT-GIRO.

  16. System analysis study of space platform and station accommodations for life sciences research facilities. Volume 2: Study results, attachment 2. Phase A: Conceptual design and programmatics

    NASA Technical Reports Server (NTRS)

    Wiley, Lowell F.

    1985-01-01

    The study results from the conceptual design and programmatics segment of the Space Platform and Station Accommodation for Life Sciences Research Facilities. The results and significant findings of the conceptual design and programmatics were generated by these tasks: (1) the review and update engineering and science requirements; (2) analysis of life sciences mission transition scenario; (3) the review and update of key trade issues; (4) the development of conceptual definition and designs; and (5) the development of the work breakdown schedule and its dictionary, program schedule, and estimated costs.

  17. Bidirectional buck boost converter

    DOEpatents

    Esser, A.A.M.

    1998-03-31

    A bidirectional buck boost converter and method of operating the same allows regulation of power flow between first and second voltage sources in which the voltage level at each source is subject to change and power flow is independent of relative voltage levels. In one embodiment, the converter is designed for hard switching while another embodiment implements soft switching of the switching devices. In both embodiments, first and second switching devices are serially coupled between a relatively positive terminal and a relatively negative terminal of a first voltage source with third and fourth switching devices serially coupled between a relatively positive terminal and a relatively negative terminal of a second voltage source. A free-wheeling diode is coupled, respectively, in parallel opposition with respective ones of the switching devices. An inductor is coupled between a junction of the first and second switching devices and a junction of the third and fourth switching devices. Gating pulses supplied by a gating circuit selectively enable operation of the switching devices for transferring power between the voltage sources. In the second embodiment, each switching device is shunted by a capacitor and the switching devices are operated when voltage across the device is substantially zero. 20 figs.

  18. Bidirectional buck boost converter

    DOEpatents

    Esser, Albert Andreas Maria

    1998-03-31

    A bidirectional buck boost converter and method of operating the same allows regulation of power flow between first and second voltage sources in which the voltage level at each source is subject to change and power flow is independent of relative voltage levels. In one embodiment, the converter is designed for hard switching while another embodiment implements soft switching of the switching devices. In both embodiments, first and second switching devices are serially coupled between a relatively positive terminal and a relatively negative terminal of a first voltage source with third and fourth switching devices serially coupled between a relatively positive terminal and a relatively negative terminal of a second voltage source. A free-wheeling diode is coupled, respectively, in parallel opposition with respective ones of the switching devices. An inductor is coupled between a junction of the first and second switching devices and a junction of the third and fourth switching devices. Gating pulses supplied by a gating circuit selectively enable operation of the switching devices for transferring power between the voltage sources. In the second embodiment, each switching device is shunted by a capacitor and the switching devices are operated when voltage across the device is substantially zero.

  19. Technologies for converter topologies

    DOEpatents

    Zhou, Yan; Zhang, Haiyu

    2017-02-28

    In some embodiments of the disclosed inverter topologies, an inverter may include a full bridge LLC resonant converter, a first boost converter, and a second boost converter. In such embodiments, the first and second boost converters operate in an interleaved manner. In other disclosed embodiments, the inverter may include a half-bridge inverter circuit, a resonant circuit, a capacitor divider circuit, and a transformer.

  20. Conceptual design for a receiving station for the nondestructive assay of PuO/sub 2/ at the fuels and materials examination facility

    SciTech Connect

    Sampson, T.E.; Speir, L.G.; Ensslin, N.; Hsue, S.T.; Johnson, S.S.; Bourret, S.; Parker, J.L.

    1981-11-01

    We propose a conceptual design for a receiving station for input accountability measurements on PuO/sub 2/ received at the Fuels and Materials Examination Facility at the Hanford Engineering Development Laboratory. Nondestructive assay techniques are proposed, including neutron coincidence counting, calorimetry, and isotopic determination by gamma-ray spectroscopy, in a versatile data acquisition system to perform input accountability measurements with precisions better than 1% at throughputs of up to 2 M.T./yr of PuO/sub 2/.

  1. Performance of Power Converters at Cryogenic Temperatures

    NASA Technical Reports Server (NTRS)

    Elbuluk, Malik E.; Gerber, Scott; Hammoud, Ahmad; Patterson, Richard L.

    2001-01-01

    Power converters capable of operation at cryogenic temperatures are anticipated to play an important role in the power system architecture of future NASA deep space missions. Design of such converters to survive cryogenic temperatures will improve the power system performance and reduce development and launch costs. Aerospace power systems are mainly a DC distribution network. Therefore, DC/DC and DC/AC converters provide the outputs needed to different loads at various power levels. Recently, research efforts have been performed at the NASA Glenn Research Center (GRC) to design and evaluate DC/DC converters that are capable of operating at cryogenic temperatures. This paper presents a summary of the research performed to evaluate the low temperature performance of five DC/DC converters. Various parameters were investigated as a function of temperature in the range of 20 to -196 C. Data pertaining to the output voltage regulation and efficiency of the converters is presented and discussed.

  2. Space Station fluid management logistics

    NASA Technical Reports Server (NTRS)

    Dominick, Sam M.

    1990-01-01

    Viewgraphs and discussion on space station fluid management logistics are presented. Topics covered include: fluid management logistics - issues for Space Station Freedom evolution; current fluid logistics approach; evolution of Space Station Freedom fluid resupply; launch vehicle evolution; ELV logistics system approach; logistics carrier configuration; expendable fluid/propellant carrier description; fluid carrier design concept; logistics carrier orbital operations; carrier operations at space station; summary/status of orbital fluid transfer techniques; Soviet progress tanker system; and Soviet propellant resupply system observations.

  3. Space station

    NASA Technical Reports Server (NTRS)

    Stewart, Donald F.; Hayes, Judith

    1989-01-01

    The history of American space flight indicates that a space station is the next logical step in the scientific pursuit of greater knowledge of the universe. The Space Station and its complement of space vehicles, developed by NASA, will add new dimensions to an already extensive space program in the United States. The Space Station offers extraordinary benefits for a comparatively modest investment (currently estimated at one-ninth the cost of the Apollo Program). The station will provide a permanent multipurpose facility in orbit necessary for the expansion of space science and technology. It will enable significant advancements in life sciences research, satellite communications, astronomy, and materials processing. Eventually, the station will function in support of the commercialization and industrialization of space. Also, as a prerequisite to manned interplanetary exploration, the long-duration space flights typical of Space Station missions will provide the essential life sciences research to allow progressively longer human staytime in space.

  4. A novel design of combining the angiotensin converting enzyme (ACE) inhibitor captopril with the angiotensin receptor blocker (ARB) losartan using homo coupling via PEG diacid linker.

    PubMed

    Hashemzadeh, Mehrnoosh; Park, Shery; Ju, Hee; Movahed, Mohammad R

    2013-12-01

    Cardiovascular disease is the leading cause of death in American adults. Furthermore, the incidence of congestive heart failure is on the rise as a major cause of hospitalization and mortality in this population. Angiotensin Converting Enzyme (ACE) inhibitors prevent the production of angiotensin II, which has been shown to reduce mortality in patients with congestive heart failure. Angiotensin II receptor blockers (ARB) were developed as a direct inhibitor of angiotensin II. ARBs have been shown to be effective in the treatment of patients with systolic heart failure but do not cause chronic coughing which is a common side effect of ACE inhibitors. In theory, a compound that has the combined effect of an ACE inhibitor and an ARB should be more effective in treating heart failure patients than either agents alone. Therefore, the purpose of this manuscript is to design and discuss the benefits of a new molecule, which combines captopril, an ACE inhibitor, with losartan, an ARB. In this experiment Captopril and Losartan were modified and synthesized separately and combined by homo or mono coupling. This was achieved by taking advantage of PEG (Polyethylene glycol) as a linker. It is expected that this molecule will have the combined modes of action of both ACEs and ARBs. Benefits from combination therapy include; increased efficacy, reduced adverse effects, convenience, compliance, and prolonged duration. Consequently, this combined molecule is expected to block the production of angiotensin II more efficiently and effectively. Although captopril and losartan work in the same system by blocking the effect of angiotensin II they have different action sites and mechanisms some patents are also discussed. Losartan blocks the AT1 receptor which is expressed on the cell surface, while captopril inhibits ACE, preventing production of angiotensin II, which is present in both the plasma and on the cell surface, especially on endothelial and smooth muscle cells.

  5. Space Station

    NASA Technical Reports Server (NTRS)

    Anderton, D. A.

    1985-01-01

    The official start of a bold new space program, essential to maintain the United States' leadership in space was signaled by a Presidential directive to move aggressively again into space by proceeding with the development of a space station. Development concepts for a permanently manned space station are discussed. Reasons for establishing an inhabited space station are given. Cost estimates and timetables are also cited.

  6. Design of a 2-Hour Prebreathe Protocol for Space Walks (EVAs) from the International Space Station (ISS)

    NASA Technical Reports Server (NTRS)

    Gernhardt, M. L.; Conkin, J.; Foster, P. P.; Pilmanis, A. A.; Butler, B. D.; Fife, C.; Vann, R. D.; Gerth, W. A.; Loftin, K. C.; Dervay, J.; Waligora, J. M.; Powell, M. R.; Homick, Jerry L. (Technical Monitor)

    2000-01-01

    The majority of extravehicular activities (EVAs) performed from the shuttle use a 10.2 psi staged decompression. The International Space Station (ISS) will operate at 14.7 psi, requiring crews to "campout" in the airlock at 10.2 psi. The constraints associated with campout (crew isolation, oxygen usage, and waste management), provided the rationale to develop a 2-hour prebreathe protocol from 14.7 psi. Previous studies on the affect of microgravity and exercise during prebreathe suggested the feasibility of this approach. Various combinations of adynamia (nonwalking subjects), prebreathe exercise doses, and space suit donning options (10.2 vs. 14.7 psi) were analyzed against timeline and consumable constraints. Prospective decompression sickness (DCS) and venous gas emboli (VGE) accept/reject criteria were defined from statistical analysis of historical DCS data, combined with risk management of DCS under ISS mission circumstances. Maximum operational DCS levels were defined based on protecting for EVA capability with two crew members at 95% confidence, throughout ISS lifetime (within the constraints of NASA DCS disposition policy JPG 1800.3). The accept / reject limits were adjusted for greater safety (including Grade IV VGE criteria) based on analysis of related medical factors. Monte-Carlo simulation was performed to design a closed sequential, multi-center laboratory trial, including the capability of rejecting the primary protocol and testing at least one alternate exercise dose, within the 2-hour prebreathe. The 2-hour protocol incorporates 0, breathing for 5 0 min at 14.7 psi, including 10 min dual cycle ergometry at 75%VO(2max). It requires an additional 30 minO2breathing during depress from 14.7 to 10.2 psi, followed by a 30-60 min suit donning break at 10.2 psi/26.5% O2. It concludes with a 40 min in-suit O2 prebreathe. The protocol would be accepted for operations, if the incidence of DCS was less than 15% and Grade IV VGE less than 20%, both at 95

  7. Rotorcraft convertible engine study

    NASA Technical Reports Server (NTRS)

    Gill, J. C.; Earle, R. V.; Mar, H. M.

    1982-01-01

    The objective of the Rotorcraft Convertible Engine Study was to define future research and technology effort required for commercial development by 1988 of convertible fan/shaft gas turbine engines for unconventional rotorcraft transports. Two rotorcraft and their respective missions were defined: a Fold Tilt Rotor aircraft and an Advancing Blade Concept (ABC) rotorcraft. Sensitivity studies were conducted with these rotorcraft to determine parametrically the influence of propulsion characteristics on aircraft size, mission fuel requirements, and direct operating costs (DOC). The two rotorcraft were flown with conventional propulsion systems (separate lift/cruise engines) and with convertible propulsion systems to determine the benefits to be derived from convertible engines. Trade-off studies were conducted to determine the optimum engine cycle and staging arrangement for a convertible engine. Advanced technology options applicable to convertible engines were studied. Research and technology programs were identified which would ensure technology readiness for commercial development of convertible engines by 1988.

  8. Manned remote work station development article. Volume 1, book 2, appendix B: Trade and design definition studies

    NASA Technical Reports Server (NTRS)

    1979-01-01

    System trades, evaluations, and selection were organized under the appropriate manned remote work station roles and subsystems. Those trades/evaluations that have an impact on simulator fidelity were given emphasis in terms of identifying alternate concepts, making a selection, and defining the system approach. Those trades that do not impact simulator fidelity have the issues delineated and future study requirements identified.

  9. Microbiological Tests Performed During the Design of the International Space Station ECLSS: Part 1, Bulk Phase Water and Wastewater

    NASA Technical Reports Server (NTRS)

    Roman, Monsi C.; Mittelman, Marc W.

    2010-01-01

    This slide presentation summarizes the studies performed to assess the bulk phase microbial community during the Space Station Water Recover Tests (WRT) from 1990-1998. These tests show that it is possible to recycle water from different sources including urine, and produce water that can exceed the quality of municpally produced tap water.

  10. A preliminary human factors planning and design outline of parameters related to space station windows and CCTV monitoring

    NASA Technical Reports Server (NTRS)

    Haines, R. F.

    1985-01-01

    The question of the merits of placing windows on proposed future space stations is addressed. The use of windows for human visual capabilities is compared to using closed circuit television. Placement and field of view, as well as the number of windows is discussed.

  11. Enabler operator station

    NASA Astrophysics Data System (ADS)

    Bailey, Andrea; Keitzman, John; King, Shirlyn; Stover, Rae; Wegner, Torsten

    The objective of this project was to design an onboard operator station for the conceptual Lunar Work Vehicle (LWV). This LWV would be used in the colonization of a lunar outpost. The details that follow, however, are for an earth-bound model. Several recommendations are made in the appendix as to the changes needed in material selection for the lunar environment. The operator station is designed dimensionally correct for an astronaut wearing the current space shuttle EVA suit (which includes life support). The proposed operator station will support and restrain an astronaut as well as provide protection from the hazards of vehicle rollover. The threat of suit puncture is eliminated by rounding all corners and edges. A step-plate, located at the front of the vehicle, provides excellent ease of entry and exit. The operator station weight requirements are met by making efficient use of grid members, semi-rigid members and woven fabrics.

  12. Enabler operator station

    NASA Technical Reports Server (NTRS)

    Bailey, Andrea; Kietzman, John; King, Shirlyn; Stover, Rae; Wegner, Torsten

    1992-01-01

    The objective of this project was to design an onboard operator station for the conceptual Lunar Work Vehicle (LWV). The LWV would be used in the colonization of a lunar outpost. The details that follow, however, are for an Earth-bound model. The operator station is designed to be dimensionally correct for an astronaut wearing the current space shuttle EVA suit (which include life support). The proposed operator station will support and restrain an astronaut as well as to provide protection from the hazards of vehicle rollover. The threat of suit puncture is eliminated by rounding all corners and edges. A step-plate, located at the front of the vehicle, provides excellent ease of entry and exit. The operator station weight requirements are met by making efficient use of rigid members, semi-rigid members, and woven fabrics.

  13. Space station operations management

    NASA Technical Reports Server (NTRS)

    Cannon, Kathleen V.

    1989-01-01

    Space Station Freedom operations management concepts must be responsive to the unique challenges presented by the permanently manned international laboratory. Space Station Freedom will be assembled over a three year period where the operational environment will change as significant capability plateaus are reached. First Element Launch, Man-Tended Capability, and Permanent Manned Capability, represent milestones in operational capability that is increasing toward mature operations capability. Operations management concepts are being developed to accomodate the varying operational capabilities during assembly, as well as the mature operational environment. This paper describes operations management concepts designed to accomodate the uniqueness of Space Station Freedoom, utilizing tools and processes that seek to control operations costs.

  14. Combination solar photovoltaic heat engine energy converter

    NASA Technical Reports Server (NTRS)

    Chubb, Donald L.

    1987-01-01

    A combination solar photovoltaic heat engine converter is proposed. Such a system is suitable for either terrestrial or space power applications. The combination system has a higher efficiency than either the photovoltaic array or the heat engine alone can attain. Advantages in concentrator and radiator area and receiver mass of the photovoltaic heat engine system over a heat-engine-only system are estimated. A mass and area comparison between the proposed space station organic Rankine power system and a combination PV-heat engine system is made. The critical problem for the proposed converter is the necessity for high temperature photovoltaic array operation. Estimates of the required photovoltaic temperature are presented.

  15. The Princess Elisabeth Station

    NASA Technical Reports Server (NTRS)

    Berte, Johan

    2012-01-01

    Aware of the increasing impact of human activities on the Earth system, Belgian Science Policy Office (Belspo) launched in 1997 a research programme in support of a sustainable development policy. This umbrella programme included the Belgian Scientific Programme on Antarctic Research. The International Polar Foundation, an organization led by the civil engineer and explorer Alain Hubert, was commissioned by the Belgian Federal government in 2004 to design, construct and operate a new Belgian Antarctic Research Station as an element under this umbrella programme. The station was to be designed as a central location for investigating the characteristic sequence of Antarctic geographical regions (polynia, coast, ice shelf, ice sheet, marginal mountain area and dry valleys, inland plateau) within a radius of 200 kilometers (approx.124 miles) of a selected site. The station was also to be designed as "state of the art" with respect to sustainable development, energy consumption, and waste disposal, with a minimum lifetime of 25 years. The goal of the project was to build a station and enable science. So first we needed some basic requirements, which I have listed here; plus we had to finance the station ourselves. Our most important requirement was that we decided to make it a zero emissions station. This was both a philosophical choice as we thought it more consistent with Antarctic Treaty obligations and it was also a logistical advantage. If you are using renewable energy sources, you do not have to bring in all the fuel.

  16. Interleaved power converter

    DOEpatents

    Zhu, Lizhi

    2007-11-13

    A power converter architecture interleaves full bridge converters to alleviate thermal management problems in high current applications, and may, for example, double the output power capability while reducing parts count and costs. For example, one phase of a three phase inverter is shared between two transformers, which provide power to a rectifier such as a current doubler rectifier to provide two full bridge DC/DC converters with three rather than four high voltage inverter legs.

  17. The photoelectric displacement converter

    NASA Astrophysics Data System (ADS)

    Dragoner, Valeriu V.

    2005-02-01

    In the article are examined questions of constructing photoelectric displacement converter satisfying demands that are stated above. Converter has channels of approximate and precise readings. The approximate reading may be accomplished either by the method of reading from a code mask or by the method of the consecutive calculation of optical scale gaps number. Phase interpolator of mouar strips" gaps is determined as a precise measuring. It is shown mathematical model of converter that allow evaluating errors and operating speed of conversion.

  18. Design Study Conducted of a Stirred and Perfused Specimen Chamber for Culturing Suspended Cells on the International Space Station

    NASA Technical Reports Server (NTRS)

    Nelson, Emily S.; Kizito, John P.

    2003-01-01

    A tightly knit numerical/experimental collaboration among the NASA Ames Research Center, NASA Glenn Research Center, and Payload Systems, Inc., was formed to analyze cell culturing systems for the International Space Station. The Cell Culture Unit is a facility scheduled for deployment on the space station by the Cell Culture Unit team at Ames. The facility houses multiple cell specimen chambers (CSCs), all of which have inlets and outlets to allow for replenishment of nutrients and for waste removal. For improved uniformity of nutrient and waste concentrations, each chamber has a pair of counterrotating stir bars as well. Although the CSC can be used to grow a wide variety of organic cells, the current study uses yeast as a model cell. Previous work identified groundbased protocols for perfusion and stirring to achieve yeast growth within the CSC that is comparable to that for yeast cultures grown in a shaken Ehrlenmeyer flask.

  19. Compressor noise control begins with design--Part 2. [Noise pollution control for natural gas pipeline compressor stations

    SciTech Connect

    Frank, L. )

    1993-09-01

    Reduction of noise pollution at gas compressor stations associated with natural gas pipelines and distribution systems, has long been a complex problem. Specified noise levels of individual components tell nothing of the overall system when it is installed and placed in a site-specific setting. Further, testing for compliance performance guarantees is virtually impossible to conduct at a distant location because one cannot distinguish among various contributing noise sources. This paper develops a plan for calculating an estimate of sound generation from a compressor station and the methods for controlling and measuring sounds of individual components. It also classifies the types of noise and gives various methods of dealing with each noise type.

  20. PWM converter topologies

    NASA Astrophysics Data System (ADS)

    Meerman, E. R. W.; Spruyt, H. J. N.

    1989-08-01

    Dc to dc converters using an electrical switch to control power flow between a dc source and a dc load are discussed. Only Pulse Width Modulation (PWM) type converter topologies are considered. A basic three element, three terminal converter topology is defined followed by two universal rules allowing for derivation of a wide variety of different topologies. A summary of different topology types is provided with steady state and small signal relations given for each. The survey shows 46 converter topologies of which 18 are known and 28 are new (under, patent application). The number of topologies could be increased to 68 if negative input voltages are considered.

  1. THERMIONIC CONVERTER SURFACE CONDITIONS.

    DTIC Science & Technology

    THERMIONIC CONVERTERS , *THERMIONIC EMISSION, SURFACE PROPERTIES, MATERIALS, CESIUM, VAPORS, NIOBIUM COMPOUNDS, CARBIDES, MOLYBDENUM, TANTALUM, TUNGSTEN, NICKEL, RHENIUM, ELECTRODES, VOLTAGE, PERFORMANCE(ENGINEERING).

  2. HEAT DIODE CONVERTER

    DTIC Science & Technology

    DIODES, * ELECTRIC POWER PRODUCTION, *REFRACTORY MATERIALS, *THERMIONIC EMISSION, CESIUM, COPPER, DISCHARGE TUBES, ELECTRONS, EVAPORATION, MOLYBDENUM...PLASMAS(PHYSICS), POWER SUPPLIES, REFLECTION, THERMAL CONDUCTIVITY, THERMIONIC CONVERTERS , VAPORS.

  3. FISSION HEAT DIODE CONVERTER

    DTIC Science & Technology

    CESIUM, *DIODES, * ELECTRIC POWER PRODUCTION, ADSORPTION, AUXILIARY POWER PLANTS, ELECTRONS, OSCILLATION, PLASMAS(PHYSICS), POWER SUPPLIES...SCATTERING, SOURCES, SPACECRAFT, THERMAL CONDUCTIVITY, THERMIONIC CONVERTERS , THERMIONIC EMISSION, TUNGSTEN, VAPORS

  4. Design of a Free and Open Source Data Processing, Archiving, and Distribution Subsystem for the Ground Receiving Station of the Philippine Scientific Earth Observation Micro-Satellite

    NASA Astrophysics Data System (ADS)

    Aranas, R. K. D.; Jiao, B. J. D.; Magallon, B. J. P.; Ramos, M. K. F.; Amado, J. A.; Tamondong, A. M.; Tupas, M. E. A.

    2016-06-01

    The Philippines's PHL-Microsat program aims to launch its first earth observation satellite, DIWATA, on the first quarter of 2016. DIWATA's payload consists of a high-precision telescope (HPT), spaceborne multispectral imager (SMI) with liquid crystal tunable filter (LCTF), and a wide field camera (WFC). Once launched, it will provide information about the Philippines, both for disaster and environmental applications. Depending on the need, different remote sensing products will be generated from the microsatellite sensors. This necessitates data processing capability on the ground control segment. Rather than rely on commercial turnkey solutions, the PHL-Microsat team, specifically Project 3:DPAD, opted to design its own ground receiving station data subsystems. This paper describes the design of the data subsystems of the ground receiving station (GRS) for DIWATA. The data subsystems include: data processing subsystem for automatic calibration and georeferencing of raw images as well as the generation of higher level processed data products; data archiving subsystem for storage and backups of both raw and processed data products; and data distribution subsystem for providing a web-based interface and product download facility for the user community. The design covers the conceptual design of the abovementioned subsystems, the free and open source software (FOSS) packages used to implement them, and the challenges encountered in adapting the existing FOSS packages to DIWATA GRS requirements.

  5. Proposal and design of a natural gas liquefaction process recovering the energy obtained from the pressure reducing stations of high-pressure pipelines

    NASA Astrophysics Data System (ADS)

    Tan, Hongbo; Zhao, Qingxuan; Sun, Nannan; Li, Yanzhong

    2016-12-01

    Taking advantage of the refrigerating effect in the expansion at an appropriate temperature, a fraction of high-pressure natural gas transported by pipelines could be liquefied in a city gate station through a well-organized pressure reducing process without consuming any extra energy. The authors proposed such a new process, which mainly consists of a turbo-expander driven booster, throttle valves, multi-stream heat exchangers and separators, to yield liquefied natural gas (LNG) and liquid light hydrocarbons (LLHs) utilizing the high-pressure of the pipelines. Based on the assessment of the effects of several key parameters on the system performance by a steady-state simulation in Aspen HYSYS, an optimal design condition of the proposed process was determined. The results showed that the new process is more appropriate to be applied in a pressure reducing station (PRS) for the pipelines with higher pressure. For the feed gas at the pressure of 10 MPa, the maximum total liquefaction rate (ytot) of 15.4% and the maximum exergy utilizing rate (EUR) of 21.7% could be reached at the optimal condition. The present process could be used as a small-scale natural gas liquefying and peak-shaving plant at a city gate station.

  6. 47 CFR 73.1820 - Station log.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Station log. 73.1820 Section 73.1820... Rules Applicable to All Broadcast Stations § 73.1820 Station log. (a) Entries must be made in the station log either manually by a person designated by the licensee who is in actual charge of...

  7. 47 CFR 73.1820 - Station log.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 4 2014-10-01 2014-10-01 false Station log. 73.1820 Section 73.1820... Rules Applicable to All Broadcast Stations § 73.1820 Station log. (a) Entries must be made in the station log either manually by a person designated by the licensee who is in actual charge of...

  8. 47 CFR 73.1820 - Station log.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 4 2013-10-01 2013-10-01 false Station log. 73.1820 Section 73.1820... Rules Applicable to All Broadcast Stations § 73.1820 Station log. (a) Entries must be made in the station log either manually by a person designated by the licensee who is in actual charge of...

  9. 47 CFR 73.1820 - Station log.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 4 2012-10-01 2012-10-01 false Station log. 73.1820 Section 73.1820... Rules Applicable to All Broadcast Stations § 73.1820 Station log. (a) Entries must be made in the station log either manually by a person designated by the licensee who is in actual charge of...

  10. 47 CFR 73.1820 - Station log.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 4 2011-10-01 2011-10-01 false Station log. 73.1820 Section 73.1820... Rules Applicable to All Broadcast Stations § 73.1820 Station log. (a) Entries must be made in the station log either manually by a person designated by the licensee who is in actual charge of...

  11. Space station accommodations for life sciences research facilities. Phase 1: Conceptual design and programmatics studies for Missions SAAX0307, SAAX0302 and the transition from SAAX0307 to SAAX0302. Volume 2: Study results

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Lockheed Missiles and Space Company's conceptual designs and programmatics for a Space Station Nonhuman Life Sciences Research Facility (LSRF) are presented. Conceptual designs and programmatics encompass an Initial Orbital Capability (IOC) LSRF, a growth or follow-on Orbital Capability (FOC), and the transitional process required to modify the IOC LSFR to the FOC LSFR. The IOC and FOC LSFRs correspond to missions SAAX0307 and SAAX0302 of the Space Station Mission Requirements Database, respectively.

  12. Stations Outdoors

    ERIC Educational Resources Information Center

    Madison, John P.; And Others

    1976-01-01

    Described is a program of outdoor education utilizing activity-oriented learning stations. Described are 13 activities including: a pond study, orienteering, nature crafts, outdoor mathematics, linear distance measurement, and area measurement. (SL)

  13. Photocapacitive image converter

    NASA Astrophysics Data System (ADS)

    Miller, W. E.; Sher, A.; Tsuo, Y. H.

    1982-05-01

    An apparatus for converting a radiant energy image into corresponding electrical signals including an image converter is described. The image converter includes a substrate of semiconductor material, an insulating layer on the front surface of the substrate, and an electrical contact on the back surface of the substrate. A first series of parallel transparent conductive stripes is on the insulating layer with a processing circuit connected to each of the conductive stripes for detecting the modulated voltages generated thereon. In a first embodiment of the invention, a modulated light stripe perpendicular to the conductive stripes scans the image converter. In a second embodiment a second insulating layer is deposited over the conductive stripes and a second series of parallel transparent conductive stripes perpendicular to the first series is on the second insulating layer. A different frequency current signal is applied to each of the second series of conductive stripes and a modulated image is applied to the image converter.

  14. Cascaded resonant bridge converters

    NASA Technical Reports Server (NTRS)

    Stuart, Thomas A. (Inventor)

    1989-01-01

    A converter for converting a low voltage direct current power source to a higher voltage, high frequency alternating current output for use in an electrical system where it is desired to use low weight cables and other circuit elements. The converter has a first stage series resonant (Schwarz) converter which converts the direct current power source to an alternating current by means of switching elements that are operated by a variable frequency voltage regulator, a transformer to step up the voltage of the alternating current, and a rectifier bridge to convert the alternating current to a direct current first stage output. The converter further has a second stage series resonant (Schwarz) converter which is connected in series to the first stage converter to receive its direct current output and convert it to a second stage high frequency alternating current output by means of switching elements that are operated by a fixed frequency oscillator. The voltage of the second stage output is controlled at a relatively constant value by controlling the first stage output voltage, which is accomplished by controlling the frequency of the first stage variable frequency voltage controller in response to second stage voltage. Fault tolerance in the event of a load short circuit is provided by making the operation of the first stage variable frequency voltage controller responsive to first and second stage current limiting devices. The second stage output is connected to a rectifier bridge whose output is connected to the input of the second stage to provide good regulation of output voltage wave form at low system loads.

  15. Space station structures development

    NASA Technical Reports Server (NTRS)

    Teller, V. B.

    1986-01-01

    A study of three interrelated tasks focusing on deployable Space Station truss structures is discussed. Task 1, the development of an alternate deployment system for linear truss, resulted in the preliminary design of an in-space reloadable linear motor deployer. Task 2, advanced composites deployable truss development, resulted in the testing and evaluation of composite materials for struts used in a deployable linear truss. Task 3, assembly of structures in space/erectable structures, resulted in the preliminary design of Space Station pressurized module support structures. An independent, redundant support system was developed for the common United States modules.

  16. Design considerations for a Space Station radiation shield for protection from both man-made and natural sources

    NASA Technical Reports Server (NTRS)

    Bolch, Wesley E.; Peddicord, K. Lee; Felsher, Harry; Smith, Simon

    1994-01-01

    This study was conducted to analyze scenarios involving the use of nuclear-power vehicles in the vicinity of a manned Space Station (SS) in low-earth-orbit (LEO) to quantify their radiological impact to the station crew. In limiting the radiant dose to crew members, mission planners may (1) shut the reactor down prior to reentry, (2) position the vehicle at a prescribed parking distance, and (3) deploy radiation shield about the shutdown reactor. The current report focuses on the third option in which point-kernel gamma-ray shielding calculations were performed for a variety of shield configurations for both nuclear electric propulsion (NEP) and nuclear thermal rocket (NTR) vehicles. For a returning NTR vehicle, calculations indicate that a 14.9 MT shield would be needed to limit the integrated crew exposure to no more than 0.05 Sv over a period of six months (25 percent of the allowable exposure to man-made radiation sources). During periods of low vehicular activity in LEO, the shield may be redeployed about the SS habitation module in order to decrease crew exposures to trapped proton radiations by approximately a factor of 10. The corresponding shield mass required for deployment at a returning NEP vehicle is 2.21 MT. Additional scenarios examined include the radioactivation of various metals as might be found in tools used in EVA activities.

  17. International Space Station US. GN&C Momentum Manager Controller Design for Shuttle Thermal Protection System Repair

    NASA Technical Reports Server (NTRS)

    Sims, Christopher R.

    2005-01-01

    This paper describes the design of the ISS Momentum Manager controllers for the Orbiter Repair Maneuver (ORM) and Orbiter Tile Repair operations. Momentum Manager Controllers provide non-propulsive attitude control via CMGs. Non-propulsive control is required at the beginning and the middle of the ORM and at the tile repair position. This paper first reviews the design issues and requirements, then presents the design methodology, and concludes with analysis results that verify the design.

  18. Space station group activities habitability module study

    NASA Technical Reports Server (NTRS)

    Nixon, David

    1986-01-01

    This study explores and analyzes architectural design approaches for the interior of the Space Station Habitability Module (originally defined as Habitability Module 1 in Space Station Reference Configuration Decription, JSC-19989, August 1984). In the Research Phase, architectural program and habitability design guidelines are specified. In the Schematic Design Phase, a range of alternative concepts is described and illustrated with drawings, scale-model photographs and design analysis evaluations. Recommendations are presented on the internal architectural, configuration of the Space Station Habitability Module for such functions as the wardroom, galley, exercise facility, library and station control work station. The models show full design configurations for on-orbit performance.

  19. About the Smart Weather Station

    NASA Astrophysics Data System (ADS)

    Bogdan, Mihai

    2016-12-01

    Until recently, the Romanian weather stations utilized ordinary transducers that acquire useful information related to the desired physical inputs. These inputs will be converted into electrical signals easy to be processed by analog to digital converters. This paper proposed a new approach based on smart sensors system that change the interior behavior in order to optimize data acquirements from the environment. The smart sensor characteristics are stored into himself in a transducer electronic data sheet form (TEDS). The intelligent transducer generat together with the measured analogic signal also a digital interface. Through this interface the transducer's catalog data can be read from the transducer.

  20. Advanced thermionic converter development

    NASA Technical Reports Server (NTRS)

    Huffman, F. N.; Lieb, D.; Briere, T. R.; Sommer, A. H.; Rufeh, F.

    1976-01-01

    Recent progress at Thermo Electron in developing advanced thermionic converters is summarized with particular attention paid to the development of electrodes, diodes, and triodes. It is found that one class of materials (ZnO, BaO and SrO) provides interesting cesiated work functions (1.3-1.4 eV) without additional oxygen. The second class of materials studied (rare earth oxides and hexaborides) gives cesiated/oxygenated work functions of less than 1.2 eV. Five techniques of oxygen addition to thermionic converters are discussed. Vapor deposited tungsten oxide collector diodes and the reflux converter are considered.