Single Stage Rocket Technology's real time data system
NASA Technical Reports Server (NTRS)
Voglewede, Steven D.
1994-01-01
The Single Stage Rocket Technology (SSRT) Delta Clipper Experimental (DC-X) Program is a United States Air Force Ballistic Missile Defense Organization (BMDO) rapid prototyping initiative that is currently demonstrating technology readiness for reusable suborbital rockets. The McDonnell Douglas DC-X rocket performed technology demonstrations at the U.S. Army White Sands Missile Range in New Mexico from April-October in 1993. The DC-X Flight Operations Control Center (FOCC) contains the ground control system that is used to monitor and control the DC-X vehicle and its Ground Support Systems (GSS). The FOCC is operated by a flight crew of three operators. Two operators manage the DC-X Flight Systems and one operator is the Ground Systems Manager. A group from McDonnell Douglas Aerospace at KSC developed the DC-X ground control system for the FOCC. This system is known as the Real Time Data System (RTDS). The RTDS is a distributed real time control and monitoring system that utilizes the latest available commercial off-the-shelf computer technology. The RTDS contains front end interfaces for the DC-X RF uplink/downlink and fiber optic interfaces to the GSS equipment. This paper describes the RTDS architecture and FOCC layout. The DC-X applications and ground operations are covered.
Initial flight qualification and operational maintenance of X-29A flight software
NASA Technical Reports Server (NTRS)
Earls, Michael R.; Sitz, Joel R.
1989-01-01
A discussion is presented of some significant aspects of the initial flight qualification and operational maintenance of the flight control system softward for the X-29A technology demonstrator. Flight qualification and maintenance of complex, embedded flight control system software poses unique problems. The X-29A technology demonstrator aircraft has a digital flight control system which incorporates functions generally considered too complex for analog systems. Organizational responsibilities, software assurance issues, tools, and facilities are discussed.
BMDS/SSA Integrated Sensing Demonstration (BISD)
NASA Astrophysics Data System (ADS)
Turner, T.; Springford, K.; Grimaldi, L.
2011-09-01
This demonstration is intended to provide a near-term prototype, leave-behind capability for integrating Ballistic Missile Defense System (BMDS) ground sensors for use in the Space Situational Awareness (SSA) mission. Closed-loop tasking and cueing capability will be implemented, and a demonstration of net-centric space data dissemination using the BMDS sensors will be undertaken using various SSA mission threads. The demonstration is designed to highlight the implications of modifying software and/or hardware at the BMDS command and control node so that cost, risk, and schedule for an operational implementation can be fully understood. Additionally, this demonstration is intended to assess the impacts to both mission areas as a multi-mission, non-traditional sensor capability is integrated into the SSA mission. A successful demonstration will have many leave-behind capabilities and first-of-its-kind achievements to include: a) an extensible SSA operational prototype configuration for BMDS X-Band radars such as AN/TPY-2 and Sea-Based X-Band (SBX) b) a prototype SSA tasking and cueing capability between the Joint Functional Component Command for Space (JFCC Space) Joint Space Operations Center (JSpOC) and the Command, Control, Battle Management, and Communications (C2BMC) Experimental Laboratory (X-Lab), extensible to the Combatant Commands (COCOMS), and out to BMDS sensors c) a capability for a twoway, net-centric, interface for JSpOC space operations, to include translation from net-centric communications to legacy systems and d) processing of BMDS X-Band Radar tracks in the Space Defense Operations Center (SPADOC).
Real-Time Control of Lean Blowout in a Turbine Engine for Minimizing No(x) Emissions
NASA Technical Reports Server (NTRS)
Zinn, Ben
2004-01-01
This report describes research on the development and demonstration of a controlled combustor operates with minimal NO, emissions, thus meeting one of NASA s UEET program goals. NO(x) emissions have been successfully minimized by operating a premixed, lean burning combustor (modeling a lean prevaporized, premixed LPP combustor) safely near its lean blowout (LBO) limit over a range of operating conditions. This was accomplished by integrating the combustor with an LBO precursor sensor and closed-loop, rule-based control system that allowed the combustor to operate far closer to the point of LBO than an uncontrolled combustor would be allowed to in a current engine. Since leaner operation generally leads to lower NO, emissions, engine NO, was reduced without loss of safety.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1991-12-31
It is the objective of the Coal Reburning for Cyclone Boiler NO{sub x} Control Project to fully establish that the cola reburning clean coal technology offers cost-effective alternatives to cyclone operating electric utilities for overall oxides of nitrogen control. The project will evaluate the applicability of the reburning technology for reducing NO{sub x} emissions in full scale cyclone-fired boilers which use coal as a primary fuel. The performance goals while burning coal are: (1) Greater than 50 percent reduction in NO{sub x} emissions, as referenced to the uncontrolled (baseline) conditions at full load. (2) No serious impact on cyclone combustormore » operation, boiler efficiency or boiler fireside performance (corrosion and deposition), or boiler ash removal system performance.« less
Coal reburning for cyclone boiler NO sub x control demonstration
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1991-01-01
It is the objective of the Coal Reburning for Cyclone Boiler NO{sub x} Control Project to fully establish that the cola reburning clean coal technology offers cost-effective alternatives to cyclone operating electric utilities for overall oxides of nitrogen control. The project will evaluate the applicability of the reburning technology for reducing NO{sub x} emissions in full scale cyclone-fired boilers which use coal as a primary fuel. The performance goals while burning coal are: (1) Greater than 50 percent reduction in NO{sub x} emissions, as referenced to the uncontrolled (baseline) conditions at full load. (2) No serious impact on cyclone combustormore » operation, boiler efficiency or boiler fireside performance (corrosion and deposition), or boiler ash removal system performance.« less
Control Synthesis for a Class of Hybrid Systems Subject to Configuration-Based Safety Constraints
NASA Technical Reports Server (NTRS)
Heymann, Michael; Lin, Feng; Meyer, George
1997-01-01
We examine a class of hybrid systems which we call Composite Hybrid Machines (CHM's) that consists of the concurrent (and partially synchronized) operation of Elementary Hybrid Machines (EHM's). Legal behavior, specified by a set of illegal configurations that the CHM may not enter, is to be achieved by the concurrent operation of the CHM with a suitably designed legal controller. In the present paper we focus on the problem of synthesizing a legal controller, whenever such a controller exists. More specifically, we address the problem of synthesizing the minimally restrictive legal controller. A controller is minimally restrictive if, when composed to operate concurrently with another legal controller, it will never interfere with the operation of the other controller and, therefore, can be composed to operate concurrently with any other controller that may be designed to achieve liveness specifications or optimality requirements without the need to reinvestigate or reverify legality of the composite controller. We confine our attention to a special class of CHM's where system dynamics is rate-limited and legal guards are conjunctions or disjunctions of atomic formulas in the dynamic variables (of the type x less than or equal to x(sub 0), or x greater than or equal to x(sub 0)). We present an algorithm for synthesis of the minimally restrictive legal controller. We demonstrate our approach by synthesizing a minimally restrictive controller for a steam boiler (the verification of which recently received a great deal of attention).
X-33 Reusable Launch Vehicle Demonstrator, Spaceport and Range
NASA Technical Reports Server (NTRS)
Letchworth, Gary F.
2011-01-01
The X-33 was a suborbital reusable spaceplane demonstrator, in development from 1996 to early 2001. The intent of the demonstrator was to lower the risk of building and operating a full-scale reusable vehicle fleet. Reusable spaceplanes offered the potential to lower the cost of access to space by an order of magnitude, compared with conventional expendable launch vehicles. Although a cryogenic tank failure during testing ultimately led to the end of the effort, the X-33 team celebrated many successes during the development. This paper summarizes some of the accomplishments and milestones of this X-vehicle program, from the perspective of an engineer who was a member of the team throughout the development. X-33 Program accomplishments include rapid, flight hardware design, subsystem testing and fabrication, aerospike engine development and testing, Flight Operations Center and Operations Control Center ground systems design and construction, rapid Environmental Impact Statement NEPA process approval, Range development and flight plan approval for test flights, and full-scale system concept design and refinement. Lessons from the X-33 Program may have potential application to new RLV and other aerospace systems being developed a decade later.
Technical challenges in the construction of the steady-state stellarator Wendelstein 7-X
NASA Astrophysics Data System (ADS)
Bosch, H.-S.; Wolf, R. C.; Andreeva, T.; Baldzuhn, J.; Birus, D.; Bluhm, T.; Bräuer, T.; Braune, H.; Bykov, V.; Cardella, A.; Durodié, F.; Endler, M.; Erckmann, V.; Gantenbein, G.; Hartmann, D.; Hathiramani, D.; Heimann, P.; Heinemann, B.; Hennig, C.; Hirsch, M.; Holtum, D.; Jagielski, J.; Jelonnek, J.; Kasparek, W.; Klinger, T.; König, R.; Kornejew, P.; Kroiss, H.; Krom, J. G.; Kühner, G.; Laqua, H.; Laqua, H. P.; Lechte, C.; Lewerentz, M.; Maier, J.; McNeely, P.; Messiaen, A.; Michel, G.; Ongena, J.; Peacock, A.; Pedersen, T. S.; Riedl, R.; Riemann, H.; Rong, P.; Rust, N.; Schacht, J.; Schauer, F.; Schroeder, R.; Schweer, B.; Spring, A.; Stäbler, A.; Thumm, M.; Turkin, Y.; Wegener, L.; Werner, A.; Zhang, D.; Zilker, M.; Akijama, T.; Alzbutas, R.; Ascasibar, E.; Balden, M.; Banduch, M.; Baylard, Ch.; Behr, W.; Beidler, C.; Benndorf, A.; Bergmann, T.; Biedermann, C.; Bieg, B.; Biel, W.; Borchardt, M.; Borowitz, G.; Borsuk, V.; Bozhenkov, S.; Brakel, R.; Brand, H.; Brown, T.; Brucker, B.; Burhenn, R.; Buscher, K.-P.; Caldwell-Nichols, C.; Cappa, A.; Cardella, A.; Carls, A.; Carvalho, P.; Ciupiński, Ł.; Cole, M.; Collienne, J.; Czarnecka, A.; Czymek, G.; Dammertz, G.; Dhard, C. P.; Davydenko, V. I.; Dinklage, A.; Drevlak, M.; Drotziger, S.; Dudek, A.; Dumortier, P.; Dundulis, G.; Eeten, P. v.; Egorov, K.; Estrada, T.; Faugel, H.; Fellinger, J.; Feng, Y.; Fernandes, H.; Fietz, W. H.; Figacz, W.; Fischer, F.; Fontdecaba, J.; Freund, A.; Funaba, T.; Fünfgelder, H.; Galkowski, A.; Gates, D.; Giannone, L.; García Regaña, J. M.; Geiger, J.; Geißler, S.; Greuner, H.; Grahl, M.; Groß, S.; Grosman, A.; Grote, H.; Grulke, O.; Haas, M.; Haiduk, L.; Hartfuß, H.-J.; Harris, J. H.; Haus, D.; Hein, B.; Heitzenroeder, P.; Helander, P.; Heller, R.; Hidalgo, C.; Hildebrandt, D.; Höhnle, H.; Holtz, A.; Holzhauer, E.; Holzthüm, R.; Huber, A.; Hunger, H.; Hurd, F.; Ihrke, M.; Illy, S.; Ivanov, A.; Jablonski, S.; Jaksic, N.; Jakubowski, M.; Jaspers, R.; Jensen, H.; Jenzsch, H.; Kacmarczyk, J.; Kaliatk, T.; Kallmeyer, J.; Kamionka, U.; Karaleviciu, R.; Kern, S.; Keunecke, M.; Kleiber, R.; Knauer, J.; Koch, R.; Kocsis, G.; Könies, A.; Köppen, M.; Koslowski, R.; Koshurinov, J.; Krämer-Flecken, A.; Krampitz, R.; Kravtsov, Y.; Krychowiak, M.; Krzesinski, G.; Ksiazek, I.; Kubkowska, M.; Kus, A.; Langish, S.; Laube, R.; Laux, M.; Lazerson, S.; Lennartz, M.; Li, C.; Lietzow, R.; Lohs, A.; Lorenz, A.; Louche, F.; Lubyako, L.; Lumsdaine, A.; Lyssoivan, A.; Maaßberg, H.; Marek, P.; Martens, C.; Marushchenko, N.; Mayer, M.; Mendelevitch, B.; Mertens, Ph.; Mikkelsen, D.; Mishchenko, A.; Missal, B.; Mizuuchi, T.; Modrow, H.; Mönnich, T.; Morizaki, T.; Murakami, S.; Musielok, F.; Nagel, M.; Naujoks, D.; Neilson, H.; Neubauer, O.; Neuner, U.; Nocentini, R.; Noterdaeme, J.-M.; Nührenberg, C.; Obermayer, S.; Offermanns, G.; Oosterbeek, H.; Otte, M.; Panin, A.; Pap, M.; Paquay, S.; Pasch, E.; Peng, X.; Petrov, S.; Pilopp, D.; Pirsch, H.; Plaum, B.; Pompon, F.; Povilaitis, M.; Preinhaelter, J.; Prinz, O.; Purps, F.; Rajna, T.; Récsei, S.; Reiman, A.; Reiter, D.; Remmel, J.; Renard, S.; Rhode, V.; Riemann, J.; Rimkevicius, S.; Riße, K.; Rodatos, A.; Rodin, I.; Romé, M.; Roscher, H.-J.; Rummel, K.; Rummel, Th.; Runov, A.; Ryc, L.; Sachtleben, J.; Samartsev, A.; Sanchez, M.; Sano, F.; Scarabosio, A.; Schmid, M.; Schmitz, H.; Schmitz, O.; Schneider, M.; Schneider, W.; Scheibl, L.; Scholz, M.; Schröder, G.; Schröder, M.; Schruff, J.; Schumacher, H.; Shikhovtsev, I. V.; Shoji, M.; Siegl, G.; Skodzik, J.; Smirnow, M.; Speth, E.; Spong, D. A.; Stadler, R.; Sulek, Z.; Szabó, V.; Szabolics, T.; Szetefi, T.; Szökefalvi-Nagy, Z.; Tereshchenko, A.; Thomsen, H.; Thumm, M.; Timmermann, D.; Tittes, H.; Toi, K.; Tournianski, M.; Toussaint, U. v.; Tretter, J.; Tulipán, S.; Turba, P.; Uhlemann, R.; Urban, J.; Urbonavicius, E.; Urlings, P.; Valet, S.; Van Eester, D.; Van Schoor, M.; Vervier, M.; Viebke, H.; Vilbrandt, R.; Vrancken, M.; Wauters, T.; Weissgerber, M.; Weiß, E.; Weller, A.; Wendorf, J.; Wenzel, U.; Windisch, T.; Winkler, E.; Winkler, M.; Wolowski, J.; Wolters, J.; Wrochna, G.; Xanthopoulos, P.; Yamada, H.; Yokoyama, M.; Zacharias, D.; Zajac, J.; Zangl, G.; Zarnstorff, M.; Zeplien, H.; Zoletnik, S.; Zuin, M.
2013-12-01
The next step in the Wendelstein stellarator line is the large superconducting device Wendelstein 7-X, currently under construction in Greifswald, Germany. Steady-state operation is an intrinsic feature of stellarators, and one key element of the Wendelstein 7-X mission is to demonstrate steady-state operation under plasma conditions relevant for a fusion power plant. Steady-state operation of a fusion device, on the one hand, requires the implementation of special technologies, giving rise to technical challenges during the design, fabrication and assembly of such a device. On the other hand, also the physics development of steady-state operation at high plasma performance poses a challenge and careful preparation. The electron cyclotron resonance heating system, diagnostics, experiment control and data acquisition are prepared for plasma operation lasting 30 min. This requires many new technological approaches for plasma heating and diagnostics as well as new concepts for experiment control and data acquisition.
Advanced electron cyclotron heating and current drive experiments on the stellarator Wendelstein 7-X
NASA Astrophysics Data System (ADS)
Stange, Torsten; Laqua, Heinrich Peter; Beurskens, Marc; Bosch, Hans-Stephan; Bozhenkov, Sergey; Brakel, Rudolf; Braune, Harald; Brunner, Kai Jakob; Cappa, Alvaro; Dinklage, Andreas; Erckmann, Volker; Fuchert, Golo; Gantenbein, Gerd; Gellert, Florian; Grulke, Olaf; Hartmann, Dirk; Hirsch, Matthias; Höfel, Udo; Kasparek, Walter; Knauer, Jens; Langenberg, Andreas; Marsen, Stefan; Marushchenko, Nikolai; Moseev, Dmitry; Pablant, Novomir; Pasch, Ekkehard; Rahbarnia, Kian; Mora, Humberto Trimino; Tsujimura, Toru; Turkin, Yuriy; Wauters, Tom; Wolf, Robert
2017-10-01
During the first operational phase (OP 1.1) of Wendelstein 7-X (W7-X) electron cyclotron resonance heating (ECRH) was the exclusive heating method and provided plasma start-up, wall conditioning, heating and current drive. Six gyrotrons were commissioned for OP1.1 and used in parallel for plasma operation with a power of up to 4.3 MW. During standard X2-heating the spatially localized power deposition with high power density allowed controlling the radial profiles of the electron temperature and the rotational transform. Even though W7-X was not fully equipped with first wall tiles and operated with a graphite limiter instead of a divertor, electron densities of n e > 3·1019 m-3 could be achieved at electron temperatures of several keV and ion temperatures above 2 keV. These plasma parameters allowed the first demonstration of a multipath O2-heating scenario, which is envisaged for safe operation near the X-cutoff-density of 1.2·1020 m-3 after full commissioning of the ECRH system in the next operation phase OP1.2.
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
AQUATECH Systems a business unit of Allied-Signal Inc., proposes to demonstrate the technical viability and cost effectiveness of the SOXAL process a combined SO{sub x}/NO{sub x} control process on a 3 MW equivalent flue gas slip stream from Niagara Mohawk Power Corporation, Dunkirk Steam Station Boiler No. 4, a coal fired boiler. The SOXAL process combines 90+% sulfur dioxide removal from the flue gas using a sodium based scrubbing solution and regeneration of the spent scrubbing liquor using AQUATECH Systems` proprietary bipolar membrane technology. This regeneration step recovers a stream of sulfur dioxide suitable for subsequent processing to salable sulfurmore » or sulfuric acid. Additionally 90+% control of NO{sub x} gases can be achieved in combination with conventional urea/methanol injection of NO{sub 2} gas into the duct. The SOXAL process is applicable to both utility and industrial scale boilers using either high or low sulfur coal. The SOXAL demonstration Program began September 10, 1991 and is approximately 22 months in duration. During the 6 months of scheduled operations period, expected to begin January 1992, data will be collected from the SOXAL system to define: SO{sub 2} and NO{sub x} control efficiencies; Current efficiency for the regeneration unit; Sulfate oxidation in the absorber; Make-up reagent rates; Product quality including concentrations and compositions; System integration and control philosophy; and Membrane stability and performance with respect to foulants.« less
2002-11-21
The second X-45A Unmanned Combat Air Vehicle (UCAV) technology demonstrator completed its first flight on November 21, 2002, after taking off from a dry lakebed at NASA's Dryden Flight Research Center, Edwards Air Force Base, California. X-45A vehicle two flew for approximately 30 minutes and reached an airspeed of 195 knots and an altitude of 7500 feet. This flight validated the functionality of the UCAV flight software on the second air vehicle. Dryden is supporting the DARPA/Boeing team in the design, development, integration, and demonstration of the critical technologies, processes, and system attributes leading to an operational UCAV system. Dryden support of the X-45A demonstrator system includes analysis, component development, simulations, ground and flight tests.
NASA Technical Reports Server (NTRS)
Stoliker, Patrick C.; Bosworth, John T.; Georgie, Jennifer
1997-01-01
The X-31A aircraft has a unique configuration that uses thrust-vector vanes and aerodynamic control effectors to provide an operating envelope to a maximum 70 deg angle of attack, an inherently nonlinear portion of the flight envelope. This report presents linearized versions of the X-31A longitudinal and lateral-directional control systems, with aerodynamic models sufficient to evaluate characteristics in the poststall envelope at 30 deg, 45 deg, and 60 deg angle of attack. The models are presented with detail sufficient to allow the reader to reproduce the linear results or perform independent control studies. Comparisons between the responses of the linear models and flight data are presented in the time and frequency domains to demonstrate the strengths and weaknesses of the ability to predict high-angle-of-attack flight dynamics using linear models. The X-31A six-degree-of-freedom simulation contains a program that calculates linear perturbation models throughout the X-31A flight envelope. The models include aerodynamics and flight control system dynamics that are used for stability, controllability, and handling qualities analysis. The models presented in this report demonstrate the ability to provide reasonable linear representations in the poststall flight regime.
X-48B Phase 1 Flight Maneuver Database and ICP Airspace Constraint Analysis
NASA Technical Reports Server (NTRS)
Fast, Peter Alan
2010-01-01
The work preformed during the Summer 2010 by Peter Fast. The main tasks assigned were to update and improve the X-48 Flight Maneuver Database and conduct an Airspace Constraint Analysis for the Remotely Operated Aircraft Area used to flight test Unmanned Arial Vehicles. The final task was to develop and demonstrate a working knowledge of flight control theory.
Integrated dry NO{sub x}/SO{sub 2} emissions control system performance summary
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hunt, T.; Muzio, L.J.; Smith, R.
1997-12-31
The Integrated Dry NO{sub x}/SO{sub 2} Emissions Control System was installed at Public Service Company of Colorado`s Arapahoe 4 generating station in 1992 in cooperation with the US Department of Energy (DOE) and the Electric Power Research Institute (EPRI). This full-scale 100 MWe demonstration combines low-NO{sub x} burners, overfire, air, and selective non-catalytic reduction (SNCR) for NO{sub x} control and dry sorbent injection (DSI) with or without humidification for SO{sub 2} control. Operation and testing of the Integrated Dry NO{sub x}/SO{sub 2} Emissions Control System began in August 1992 and will continue through 1996. Results of the NO{sub x} controlmore » technologies show that the original system goal of 70% NO{sub x} removal has been easily met and the combustion and SNCR systems can achieve NO{sub x} removals of up to 80% at full load. Duct injection of commercial calcium hydroxide has achieved a maximum SO{sub 2} removal of nearly 40% while humidifying the flue gas to a 20 F approach to saturation. Sodium-based dry sorbent injection has provided SO{sub 2} removal of over 70% without the occurrence of a visible NO{sub 2} plume. Recent test work has improved SNCR performance at low loads and has demonstrated that combined dry sodium injection and SNCR yields both lower NO{sub 2} levels and NH{sub 3} slip than either technology alone.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
AQUATECH Systems, a business unit of Allied-Signal Inc., proposes to demonstrate the technical viability and cost effectiveness of the SOXAL process a combined SO{sub x}/NO{sub x} control process on a 3 MW equivalent flue gas slip stream from Niagara Mohawk Power Corporation Dunkirk Steam Station Boiler No. 4, a coal fired boiler. The SOXAL process combines 90+% sulfur dioxide removal from the flue gas using a sodium based scrubbing solution and regeneration of the spent scrubbing liquor using AQUATECH Systems` proprietary bipolar membrane technology. This regeneration step recovers a stream of sulfur dioxide suitable for subsequent processing to salable sulfurmore » or sulfuric acid. Additionally 90+% control of NO{sub x} gases can be achieved in combination with conventional urea/methanol injection of NO{sub 2} gas into the duct. The SOXAL process is applicable to both utility and industrial scale boilers using either high or lower sulfur coal. The SOXAL demonstration Program began September 10, 1991 and is approximately 26 months in duration. During the 6 months of scheduled operations, between January and July of 1993, data was collected from the SOXAL system to define: SO{sub 2} and NO{sub x} control efficiencies; Current efficiency for the regeneration unit; Sulfate oxidation in the absorber; Make-up reagent rates; Product quality including concentrations and compositions; System integration and control philosophy; and Membrane stability and performance with respect to foulants. The program is expected to be concluded in November 1993.« less
NASA Technical Reports Server (NTRS)
Littlefield, Alan C.; Melton, Gregory S.
2000-01-01
The X-33 Advanced Technology Demonstrator is an un-piloted, vertical take-off, horizontal landing spacecraft. The purpose of the X-33 program is to demonstrate technologies that will dramatically lower the cost of access to space. The rocket-powered X-33 will reach an altitude of up to 100 km and speeds between Mach 13 and 15. Fifteen flight tests are planned, beginning in 2000. Some of the key technologies demonstrated will be the linear aerospike engine, improved thermal protection systems, composite fuel tanks and reduced operational timelines. The X-33 vehicle umbilical connections provide monitoring, power, cooling, purge, and fueling capability during horizontal processing and vertical launch operations. Two "rise-off" umbilicals for the X-33 have been developed, tested, and installed. The X-33 umbilical systems mechanisms incorporate several unique design features to simplify horizontal operations and provide reliable disconnect during launch.
NASA Technical Reports Server (NTRS)
Littlefield, Alan C.; Melton, Gregory S.
1999-01-01
The X-33 Advanced Technology Demonstrator is an un-piloted, vertical take-off, horizontal landing spacecraft. The purpose of the X-33 program is to demonstrate technologies that will dramatically lower the cost of access to space. The rocket-powered X-33 will reach an altitude of up to 100 km and speeds between Mach 13 and 15. Fifteen flight tests are planned, beginning in 2000. Some of the key technologies demonstrated will be the linear aerospike engine, improved thermal protection systems, composite fuel tanks and reduced operational timelines. The X-33 vehicle umbilical connections provide monitoring, power, cooling, purge, and fueling capability during horizontal processing and vertical launch operations. Two "rise-ofF' umbilicals for the X-33 have been developed, tested, and installed. The X-33 umbilical systems mechanisms incorporate several unique design features to simplify horizontal operations and provide reliable disconnect during launch.
A study of the durability of beryllium rocket engines. [space shuttle reaction control system
NASA Technical Reports Server (NTRS)
Paster, R. D.; French, G. C.
1974-01-01
An experimental test program was performed to demonstrate the durability of a beryllium INTEREGEN rocket engine when operating under conditions simulating the space shuttle reaction control system. A vibration simulator was exposed to the equivalent of 100 missions of X, Y, and Z axes random vibration to demonstrate the integrity of the recently developed injector-to-chamber braze joint. An off-limits engine was hot fired under extreme conditions of mixture ratio, chamber pressure, and orifice plugging. A durability engine was exposed to six environmental cycles interspersed with hot-fire tests without intermediate cleaning, service, or maintenance. Results from this program indicate the ability of the beryllium INTEREGEN engine concept to meet the operational requirements of the space shuttle reaction control system.
X-38 NASA/DLR/ESA-Dassault Aviation Integrated Aerodynamic and Aerothermodynamic Activities
NASA Technical Reports Server (NTRS)
Labbe, Steve G.; Perez, Leo F.; Fitzgerald, Steve; Longo, Jose; Rapuc, Marc; Molina, Rafael; Nicholson, Leonard S. (Technical Monitor)
1999-01-01
The characterization of the aeroshape selected for the X-38 [Crew Return Vehicle (CRV) demonstrator] is presently being performed as a cooperative endeavour between NASA, DLR (through its TETRA Program), and European Space Agency (ESA) with Dassault Aviation integrating the aerodynamic and aerothermodynamic activities. The methodologies selected for characterizing the aerodynamic and aerothermodynamic environment of the X-38 are presented. Also, the implications for related disciplines such as Guidance Navigation and Control (GN&C) with its corresponding Flight Control System (FCS), Structural, and Thermal Protection System (TPS) design are discussed. An attempt is made at defining the additional activities required to support the design of a derived operational CRV.
X-33, Demonstrating Revolutionary Operations for VentureStar(TM)
NASA Technical Reports Server (NTRS)
Austin, Robert E.; Ishmael, Stephen D.; Lacefield, Cleon
2000-01-01
The X-33, reusable space plane technology demonstrator is on course to begin the flights of the X-33 by the end of 2002 that will serve as a basis for industry and government decisions that could lead to VentureStar(Trademark). Lockheed Martin has placed the VentureStar LLC in it's Space Company and is now competing in an industry wide effort that will permit NASA to select a Second Generation RLV source by 2005. This move provides the focus for firm business planning needed to enable the decision by the time X-33 flies in mid 2002 and possibly with upgraded technologies a year or so later. The operations concept for the X-33 is an integration of launch vehicle and aircraft operations approaches. VentureStar is a Single Stage To Orbit (SSTO) and will therefore enable a new approach to Space Launch Operations that is more "aircraft like" and can produce substantially lower operating costs over current systems. NASA's initiatives over the past several years in Reusable Launch Vehicles (RLV) have had as a primary objective to demonstrate technologies that will result in significant reduction in costs of space access. Further, the end objective is to commercialize the development and operations of the next generation RLV. Hence, the X-33 and its operations demonstration is a major contributor to that next generation system.
Hyper-X Hot Structures Comparison of Thermal Analysis and Flight Data
NASA Technical Reports Server (NTRS)
Amundsen, Ruth M.; Leonard, Charles P.; Bruce, Walter E., III
2004-01-01
The Hyper-X (X-43A) program is a flight experiment to demonstrate scramjet performance and operability under controlled powered free-flight conditions at Mach 7 and 10. The Mach 7 flight was successfully completed on March 27, 2004. Thermocouple instrumentation in the hot structures (nose, horizontal tail, and vertical tail) recorded the flight thermal response of these components. Preflight thermal analysis was performed for design and risk assessment purposes. This paper will present a comparison of the preflight thermal analysis and the recorded flight data.
Demonstration of fuel switching on oceangoing vessels in the Gulf of Mexico.
Browning, Louis; Hartley, Seth; Bandemehr, Angela; Gathright, Kenneth; Miller, Wayne
2012-09-01
Switching fuels from high-sulfur heavy fuel oils (HFO) to lower sulfur marine gas oils (MGO) on an oceangoing vessel (OGV) can substantially reduce both PM and SO(x) ship stack emissions, potentially resulting in significant human health and environmental benefits in Gulf of Mexico port communities. The International Maritime Organization (IMO) established an emission control area (ECA) within 200 nautical miles of the US. and Canadian coastlines and French territories off the coast of Canada with lower fuel sulfur standards effective beginning August 2012, where OGVs will need to switch from HFO to MGO. However some operators and other stakeholders, particularly in the Gulf of Mexico, may be unfamiliar with the benefits and requirements and ship operators may be concerned over potential implications for cost and operations. This first-ever US. Environmental Protection Agency (EPA)-sponsored fuel switching demonstration in the Gulf of Mexico was initiated to showcase the environmental and health benefits of as well as operational issues associated with, fuel switching through the following activities: (1) Fuel switching was conducted on typical container ships operating the Gulf of Mexico, as routine fuel switching has been demonstrated in California in recent years. Two vessels were employed in the demonstration: the Maersk Roubaix, which switched fuels entering Port of Houston, TX, and the Port of Progreso, Mexico, and the Hamburg Süd vessel Cap San Lorenzo, which switched fuels entering the Port of Houston and the Mexican Ports of Veracruz and Altamira. Operational and cost aspects were also noted. (2) Emissions reductions were quantified through both a calculation approach based on fuel use of the Maersk Line vessel Roubaix and in-stack monitoring of emissions from the Hamburg Süd Cap San Lorenzo. Pollutant emissions including PM, SO(x), NO(x), and PM component speciation were sampled during use of both fuels. These observations showed reductions (1-6%) in NO(x) and substantial reductions in PM (50-70%) and SO(x) (> 99%) depending on engine and load. (3) Emission inventories at three ports were calculated. (4) Potential health and environmental benefits to communities and ecosystems in the Gulf of Mexico were estimated through screening-level modeling of air dispersion and atmospheric deposition of ship emissions at the Port of Veracruz to indicate the substantial reductions available through fuel switching. The United States and Canada have recently adopted a North American Emission Control Area that will require a shift from high-sulfur to low-sulfur fuels in the marine transportation sector. Cleaner fuels are expected to reduce sulfur and particulate emissions. This paper verifies the feasibility of such switching operations, the potential to reduce emissions if extended to the Gulf of Mexico, and the associated environmental impacts of these emission reductions inland and to sensitive ecosystems.
X-34 Technology Testbed Demonstrator being mated with the L-1011 mothership
1999-03-11
This is the X-34 Technology Testbed Demonstrator being mated with the L-1011 mothership. The X-34 will demonstrate key vehicle and operational technologies applicable to future low-cost resuable launch vehicles.
GNOCIS an update of the generic NO{sub x} control intelligent system
DOE Office of Scientific and Technical Information (OSTI.GOV)
Holmes, R.; Mayes, I.; Irons, R.
1996-01-01
GNOCIS is an on-line enhancement to existing power plant Digital Control Systems (DCS) designed to reduce NO{sub x} emissions while meeting other operational constraints, such as heat rate and CO emissions. It can also be used to minimize unburned carbon while meeting a specified NO{sub x} limit, or any combination of emissions/performance variables that can be quantified by a common metric and are affected by DCS - adjustable parameters. The core of the system is an adaptive neural network model of the NO{sub x} generation characteristics of the boiler. The software applies an optimizing procedure to identify the best setpointsmore » for the plant. The recommended setpoints can be either conveyed to the operator via the DCS in an advisory mode, or implemented automatically in a closed-loop mode. GNOCIS is designed to run on a stand-alone workstation connected to the DCS via the data highway. Sensor validation techniques have been incorporated. The goal for GNOSIS is to deliver 10-35% reductions in NO{sub x} from baseline conditions while maintaining or improving other operational constraints. Preliminary results are presented for demonstrations at two power plants: (1) 500-MW T-fired boiler at PowerGen`s Kingsnorth Station, (2) 250-MW Opposed-fired boiler at Alabama Power Company`s Gaston Station.« less
The Stability of Chandra Telescope Pointing and Spacial Resolution
NASA Astrophysics Data System (ADS)
Zhao, Ping
2018-01-01
Chandra X-ray Observatory revolutionized the X-ray astronomy as being the first, and so far the only, X-ray telescope achieving sub-arcsecond spacial resolution. Chandra is comprised of three principal elements: the High Resolution Mirror Assembly (HRMA), Pointing Control and Aspect Determination (PCAD) system, and the Science Instrument Module (SIM), which is where the X-ray detectors mounted and is connected to the HRMA by a 10-meter long Optical Bench Assembly. To achieve and retain the unprecedented imaging quality, it is critical that these three principal elements to stay rigid and stable for the entire life time of the Chandra operation. I will review the issues of telescope pointing stability, optical Axis, aimpoint and their impacts to the Chandra operation, and evaluate the integrity and stability of the telescope. I will show images taken from all four detectors since launch to demonstrate the quality and stability of the Chandra spacial resolution.
The Quality and Stability of Chandra Telescope Spacial Resolution
NASA Astrophysics Data System (ADS)
Zhao, Ping
2017-08-01
Chandra X-ray Observatory revolutionized the X-ray astronomy as being the first, and so far the only, X-ray telescope achieving sub-arcsecond spacial resolution. Chandra is comprised of three principal elements: the High Resolution Mirror Assembly (HRMA), Pointing Control and Aspect Determination (PCAD) system, and the Science Instrument Module (SIM), which is where the X-ray detectors mounted and is connected to the HRMA by a 10-meter long Optical Bench Assembly. To achieve and retain the unprecedented imaging quality, it is critical that these three principal elements to stay rigid and stable for the entire life time of the Chandra operation. I will review the issues of telescope pointing stability, optical Axis, aimpoint and their impacts to the Chandra operation, and evaluate the integrity and stability of the telescope. I will show images taken from all four detectors since launch to demonstrate the quality and stability of the Chandra spacial resolution.
X-34 Vehicle Aerodynamic Characteristics
NASA Technical Reports Server (NTRS)
Brauckmann, Gregory J.
1998-01-01
The X-34, being designed and built by the Orbital Sciences Corporation, is an unmanned sub-orbital vehicle designed to be used as a flying test bed to demonstrate key vehicle and operational technologies applicable to future reusable launch vehicles. The X-34 will be air-launched from an L-1011 carrier aircraft at approximately Mach 0.7 and 38,000 feet altitude, where an onboard engine will accelerate the vehicle to speeds above Mach 7 and altitudes to 250,000 feet. An unpowered entry will follow, including an autonomous landing. The X-34 will demonstrate the ability to fly through inclement weather, land horizontally at a designated site, and have a rapid turn-around capability. A series of wind tunnel tests on scaled models was conducted in four facilities at the NASA Langley Research Center to determine the aerodynamic characteristics of the X-34. Analysis of these test results revealed that longitudinal trim could be achieved throughout the design trajectory. The maximum elevon deflection required to trim was only half of that available, leaving a margin for gust alleviation and aerodynamic coefficient uncertainty. Directional control can be achieved aerodynamically except at combined high Mach numbers and high angles of attack, where reaction control jets must be used. The X-34 landing speed, between 184 and 206 knots, is within the capabilities of the gear and tires, and the vehicle has sufficient rudder authority to control the required 30-knot crosswind.
NASA Astrophysics Data System (ADS)
Kim, Seung-Tae; Cho, Won-Ju
2018-01-01
We fabricated a resistive random access memory (ReRAM) device on a Ti/AlO x /Pt structure with solution-processed AlO x switching layer using microwave irradiation (MWI), and demonstrated multi-level cell (MLC) operation. To investigate the effect of MWI power on the MLC characteristics, post-deposition annealing was performed at 600-3000 W after AlO x switching layer deposition, and the MLC operation was compared with as-deposited (as-dep) and conventional thermally annealing (CTA) treated devices. All solution-processed AlO x -based ReRAM devices exhibited bipolar resistive switching (BRS) behavior. We found that these devices have four-resistance states (2 bits) of MLC operation according to the modulation of the high-resistance state (HRSs) through reset voltage control. Particularly, compared to the as-dep and CTA ReRAM devices, the MWI-treated ReRAM devices showed a significant increase in the memory window and stable endurance for multi-level operation. Moreover, as the MWI power increased, excellent MLC characteristics were exhibited because the resistance ratio between each resistance state was increased. In addition, it exhibited reliable retention characteristics without deterioration at 25 °C and 85 °C for 10 000 s. Finally, the relationship between the chemical characteristics of the solution-processed AlO x switching layer and BRS-based multi-level operation according to the annealing method and MWI power was investigated using x-ray photoelectron spectroscopy.
Pathfinder Technologies Specialist, X-37
NASA Technical Reports Server (NTRS)
French, James R.
2001-01-01
The X-37 is a technology demonstrator sponsored by NASA. It includes a number of experiments both imbedded (i.e., essential aspects of the vehicle) and separate. The technologies demonstrated will be useful in future operational versions as well as having broad applications to other programs. Mr. James R. French, of JRF Engineering Services and as a consultant to SAIC, has provided technical support to the X-37 NASA Program office since the beginning of the program. In providing this service, Mr. French has maintained close contact with the Boeing Seal Beach and Rocketdyne technical teams via telephone, e-mail, and periodic visits. His interfaces were primarily with the working engineers in order to provide NASA sponsors with a different view than that achieved through management channels. Mr. French's periodic and highly detailed technical reports were submitted to NASA and SAIC (Science Applications International Corporation) on a weekly/monthly basis. These reports addressed a wide spectrum of programmatic and technical interests related to the X-37 Program including vehicle design, flight sciences, propulsion, thermal protection, Guidance Navigation & Control (GN&C), structures, and operations. This deliverable is presented as a consolidation of the twelve monthly reports submitted during the Contract's Option Year,
Lessons Learned from Engineering a Multi-Mission Satellite Operations Center
NASA Technical Reports Server (NTRS)
Madden, Maureen; Cary, Everett, Jr.; Esposito, Timothy; Parker, Jeffrey; Bradley, David
2006-01-01
NASA's Small Explorers (SMEX) satellites have surpassed their designed science-lifetimes and their flight operations teams are now facing the challenge of continuing operations with reduced funding. At present, these missions are being reengineered into a fleet-oriented ground system at Goddard Space Flight Center (GSFC). When completed, this ground system will provide command and control of four SMEX missions and will demonstrate fleet automation and control concepts. As a path-finder for future mission consolidation efforts, this ground system will also demonstrate new ground-based technologies that show promise of supporting longer mission lifecycles and simplifying component integration. One of the core technologies being demonstrated in the SMEiX Mission Operations Center is the GSFC Mission Services Evolution Center (GMSEC) architecture. The GMSEC architecture uses commercial Message Oriented Middleware with a common messaging standard to realize a higher level of component interoperability, allowing for interchangeable components in ground systems. Moreover, automation technologies utilizing the GMSEC architecture are being evaluated and implemented to provide extended lights-out operations. This mode of operation will provide routine monitoring and control of the heterogeneous spacecraft fleet. The operational concepts being developed will reduce the need for staffed contacts and is seen as a necessity for fleet management. This paper will describe the experiences of the integration team throughout the reengineering effort of the SMEX ground system. Additionally, lessons learned will be presented based on the team s experiences with integrating multiple missions into a fleet-based automated ground system.
Differences Between S/X and VLBI2010 Operation
NASA Technical Reports Server (NTRS)
Hase, Hayo; Himwich, Ed; Neidhardt, Alexander
2010-01-01
The intended VLBI2010 operation has some significant differences to the current S/X operation. The presentation focuses on the problem of extending the operation of a global VLBI network to continuous operation within the frame of the same given amount of human resources. Remote control operation is a suitable solution to minimize operational expenses. The implementation of remote control operation requires more site specific information. A concept of a distributed-centralized remote control of the operation and its implications is presented.
Subsystem Analysis/Optimization for the X-34 Main Propulsion System
NASA Technical Reports Server (NTRS)
McDonald, J. P.; Hedayat, A.; Brown, T. M.; Knight, K. C.; Champion, R. H., Jr.
1998-01-01
The Orbital Sciences Corporation X-34 vehicle demonstrates technologies and operations key to future reusable launch vehicles. The general flight performance goal of this unmanned rocket plane is Mach 8 flight at an altitude of 250,000 feet. The Main Propulsion System (MPS) supplies liquid propellants to the main engine, which provides the primary thrust for attaining mission goals. Major MPS design and operational goals are aircraft-like ground operations, quick turnaround between missions, and low initial/operational costs. Analyses related to optimal MPS subsystem design are reviewed in this paper. A pressurization system trade weighs maintenance/reliability concerns against those for safety in a comparison of designs using pressure regulators versus orifices to control pressurant flow. A propellant dump/feed system analysis weighs the issues of maximum allowable vehicle landing weight, trajectory, and MPS complexity to arrive at a final configuration for propellant dump/feed systems.
Fabrication Technologies of the High Gradient Accelerator Structures at 100MV/M Range
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Juwen; /SLAC; Lewandowski, James
A CERN-SLAC-KEK collaboration on high gradient X-band structure research has been established in order to demonstrate the feasibility of the CLIC baseline design for the main linac stably operating at more than 100 MV/m loaded accelerating gradient. Several prototype CLIC structures were successfully fabricated and high power tested. They operated at 105 MV/m with a breakdown rate that meets the CLIC linear collider specifications of < 5 x 10{sup -7}/pulse/m. This paper summarizes the fabrication technologies including the mechanical design, precision machining, chemical cleaning, diffusion bonding as well as vacuum baking and all related assembly technologies. Also, the tolerances control,more » tuning and RF characterization will be discussed.« less
Calibration of the Total and Static Pressure Transducers in the DSTO Transonic Wind Tunnel
2010-08-01
handled by the ActiveX control MSCOMM32.OCX which is not part of the Microsoft Windows operating system. It is, however, included as part of the...implemented new measures to register ActiveX controls in its Windows suite of operating systems, which has made the above file obsolete and it could no...longer be used if the Windows operating system were updated. If this is the case, then the new version of ActiveX control files can be installed using
The Astro-H High Resolution Soft X-Ray Spectrometer
NASA Technical Reports Server (NTRS)
Kelley, Richard L.; Akamatsu, Hiroki; Azzarell, Phillip; Bialas, Tom; Boyce, Kevin R.; Brown, Gregory V.; Canavan, Edgar; Chiao, Meng P.; Costantini, Elisa; DiPirro, Michael J.;
2016-01-01
We present the overall design and performance of the Astro-H (Hitomi) Soft X-Ray Spectrometer (SXS). The instrument uses a 36-pixel array of x-ray microcalorimeters at the focus of a grazing-incidence x-ray mirror Soft X-Ray Telescope (SXT) for high-resolution spectroscopy of celestial x-ray sources. The instrument was designed to achieve an energy resolution better than 7 eV over the 0.3-12 keV energy range and operate for more than 3 years in orbit. The actual energy resolution of the instrument is 4-5 eV as demonstrated during extensive ground testing prior to launch and in orbit. The measured mass flow rate of the liquid helium cryogen and initial fill level at launch predict a lifetime of more than 4 years assuming steady mechanical cooler performance. Cryogen-free operation was successfully demonstrated prior to launch. The successful operation of the SXS in orbit, including the first observations of the velocity structure of the Perseus cluster of galaxies, demonstrates the viability and power of this technology as a tool for astrophysics.
The Astro-H high resolution soft x-ray spectrometer
NASA Astrophysics Data System (ADS)
Kelley, Richard L.; Akamatsu, Hiroki; Azzarello, Phillipp; Bialas, Tom; Boyce, Kevin R.; Brown, Gregory V.; Canavan, Edgar; Chiao, Meng P.; Costantini, Elisa; DiPirro, Michael J.; Eckart, Megan E.; Ezoe, Yuichiro; Fujimoto, Ryuichi; Haas, Daniel; den Herder, Jan-Willem; Hoshino, Akio; Ishikawa, Kumi; Ishisaki, Yoshitaka; Iyomoto, Naoko; Kilbourne, Caroline A.; Kimball, Mark O.; Kitamoto, Shunji; Konami, Saori; Koyama, Shu; Leutenegger, Maurice A.; McCammon, Dan; Mitsuda, Kazuhisa; Mitsuishi, Ikuyuki; Moseley, Harvey; Murakami, Hiroshi; Murakami, Masahide; Noda, Hirofumi; Ogawa, Mina; Ohashi, Takaya; Okamoto, Atsushi; Ota, Naomi; Paltani, Stéphane; Porter, F. S.; Sakai, Kazuhiro; Sato, Kosuke; Sato, Yohichi; Sawada, Makoto; Seta, Hiromi; Shinozaki, Keisuke; Shirron, Peter J.; Sneiderman, Gary A.; Sugita, Hiroyuki; Szymkowiak, Andrew E.; Takei, Yoh; Tamagawa, Toru; Tashiro, Makoto; Terada, Yukikatsu; Tsujimoto, Masahiro; de Vries, Cor P.; Yamada, Shinya; Yamasaki, Noriko Y.; Yatsu, Yoichi
2016-07-01
We present the overall design and performance of the Astro-H (Hitomi) Soft X-Ray Spectrometer (SXS). The instrument uses a 36-pixel array of x-ray microcalorimeters at the focus of a grazing-incidence x-ray mirror Soft X-Ray Telescope (SXT) for high-resolution spectroscopy of celestial x-ray sources. The instrument was designed to achieve an energy resolution better than 7 eV over the 0.3-12 keV energy range and operate for more than 3 years in orbit. The actual energy resolution of the instrument is 4-5 eV as demonstrated during extensive ground testing prior to launch and in orbit. The measured mass flow rate of the liquid helium cryogen and initial fill level at launch predict a lifetime of more than 4 years assuming steady mechanical cooler performance. Cryogen-free operation was successfully demonstrated prior to launch. The successful operation of the SXS in orbit, including the first observations of the velocity structure of the Perseus cluster of galaxies, demonstrates the viability and power of this technology as a tool for astrophysics.
X-rays only when you want them: optimized pump–probe experiments using pseudo-single-bunch operation
Hertlein, M. P.; Scholl, A.; Cordones, A. A.; Lee, J. H.; Engelhorn, K.; Glover, T. E.; Barbrel, B.; Sun, C.; Steier, C.; Portmann, G.; Robin, D. S.
2015-01-01
Laser pump–X-ray probe experiments require control over the X-ray pulse pattern and timing. Here, the first use of pseudo-single-bunch mode at the Advanced Light Source in picosecond time-resolved X-ray absorption experiments on solutions and solids is reported. In this mode the X-ray repetition rate is fully adjustable from single shot to 500 kHz, allowing it to be matched to typical laser excitation pulse rates. Suppressing undesired X-ray pulses considerably reduces detector noise and improves signal to noise in time-resolved experiments. In addition, dose-induced sample damage is considerably reduced, easing experimental setup and allowing the investigation of less robust samples. Single-shot X-ray exposures of a streak camera detector using a conventional non-gated charge-coupled device (CCD) camera are also demonstrated. PMID:25931090
X-rays only when you want them: Optimized pump–probe experiments using pseudo-single-bunch operation
Hertlein, M. P.; Scholl, A.; Cordones, A. A.; ...
2015-04-02
Laser pump–X-ray probe experiments require control over the X-ray pulse pattern and timing. Here, the first use of pseudo-single-bunch mode at the Advanced Light Source in picosecond time-resolved X-ray absorption experiments on solutions and solids is reported. In this mode the X-ray repetition rate is fully adjustable from single shot to 500 kHz, allowing it to be matched to typical laser excitation pulse rates. Suppressing undesired X-ray pulses considerably reduces detector noise and improves signal to noise in time-resolved experiments. In addition, dose-induced sample damage is considerably reduced, easing experimental setup and allowing the investigation of less robust samples. Single-shotmore » X-ray exposures of a streak camera detector using a conventional non-gated charge-coupled device (CCD) camera are also demonstrated.« less
X-31 Unloading Returning from Paris Air Show
NASA Technical Reports Server (NTRS)
1995-01-01
After being flown in the Paris Air Show in June 1995, the X-31 Enhanced Fighter Maneuverability Technology Demonstrator Aircraft, based at the NASA Dryden Flight Research Center, Edwards Air Force Base, California, is off-loaded from an Air Force Reserve C-5 transport after the ferry flight back to Edwards. At the air show, the X-31 demonstrated the value of using thrust vectoring (directing engine exhaust flow) coupled with advanced flight control systems to provide controlled flight at very high angles of attack. The X-31 Enhanced Fighter Maneuverability (EFM) demonstrator flew at the Ames- Dryden Flight Research Facility, Edwards, California (redesignated the Dryden Flight Research Center in 1994) from February 1992 until 1995 and before that at the Air Force's Plant 42 in Palmdale, California. The goal of the project was to provide design information for the next generation of highly maneuverable fighter aircraft. This program demonstrated the value of using thrust vectoring (directing engine exhaust flow) coupled with an advanced flight control system to provide controlled flight to very high angles of attack. The result was a significant advantage over most conventional fighters in close-in combat situations. The X-31 flight program focused on agile flight within the post-stall regime, producing technical data to give aircraft designers a better understanding of aerodynamics, effectiveness of flight controls and thrust vectoring, and airflow phenomena at high angles of attack. Stall is a condition of an airplane or an airfoil in which lift decreases and drag increases due to the separation of airflow. Thrust vectoring compensates for the loss of control through normal aerodynamic surfaces that occurs during a stall. Post-stall refers to flying beyond the normal stall angle of attack, which in the X-31 was at a 30-degree angle of attack. During Dryden flight testing, the X-31 aircraft established several milestones. On November 6, 1992, the X-31 achieved controlled flight at a 70-degree angle of attack. On April 29, 1993, the second X-31 successfully executed a rapid minimum-radius, 180-degree turn using a post-stall maneuver, flying well beyond the aerodynamic limits of any conventional aircraft. This revolutionary maneuver has been called the 'Herbst Maneuver' after Wolfgang Herbst, a German proponent of using post-stall flight in air-to-air combat. It is also called a 'J Turn' when flown to an arbitrary heading change. The aircraft was flown in tactical maneuvers against an F/A-18 and other tactical aircraft as part of the test flight program. During November and December 1993, the X-31 reached a supersonic speed of Mach 1.28. In 1994, the X-31 program installed software to demonstrate quasi-tailless operation. The X-31 flight test program was conducted by an international test organization (ITO) managed by the Advanced Research Projects Office (ARPA), known as the Defense Advanced Research Projects Office (DARPA) before March 1993. The ITO included the U.S. Navy and U.S. Air Force, Rockwell Aerospace, the Federal Republic of Germany, Daimler-Benz (formerly Messerschmitt-Bolkow-Blohm and Deutsche Aerospace), and NASA. Gary Trippensee was the ITO director and NASA Project Manager. Pilots came from participating organizations. The X-31 was 43.33 feet long with a wingspan of 23.83 feet. It was powered by a single General Electric P404-GE-400 turbofan engine that produced 16,000 pounds of thrust in afterburner.
Operation Of The X-29A Digital Flight-Control System
NASA Technical Reports Server (NTRS)
Chacon, Vince; Mcbride, David
1990-01-01
Report reviews program of testing and evaluation of digital flight-control system for X-29A airplane, with emphasis on operation during tests. Topics include design of system, special electronic testing equipment designed to aid in daily operations, and aspects of testing, including detection of faults.
Experience with ActiveX control for simple channel access
DOE Office of Scientific and Technical Information (OSTI.GOV)
Timossi, C.; Nishimura, H.; McDonald, J.
2003-05-15
Accelerator control system applications at Berkeley Lab's Advanced Light Source (ALS) are typically deployed on operator consoles running Microsoft Windows 2000 and utilize EPICS[2]channel access for data access. In an effort to accommodate the wide variety of Windows based development tools and developers with little experience in network programming, ActiveX controls have been deployed on the operator stations. Use of ActiveX controls for use in the accelerator control environment has been presented previously[1]. Here we report on some of our experiences with the use and development of these controls.
NASA Technical Reports Server (NTRS)
Tacina, Robert R. (Technical Monitor); Rosfjord, T. J.; Padget, F. C.
2001-01-01
In support of Pratt & Whitney efforts to define the Rich burn/Quick mix/Lean burn (RQL) combustor for the High Speed Civil Transport (HSCT) aircraft engine, UTRC conducted a flametube-scale study of the RQL concept. Extensive combustor testing was performed at the Supersonic Cruise (SSC) condition of an HSCT engine cycle. Data obtained from probe traverses near the exit of the mixing section confirmed that the mixing section was the critical component in controlling combustor emissions. Circular-hole configurations, which produced rapidly-, highly-penetrating jets, were most effective in limiting NO(x). The spatial profiles of NO(x) and CO at the mixer exit were not directly interpretable using a simple flow model based on jet penetration, and a greater understanding of the flow and chemical processes in this section are required to optimize it. Neither the rich-combustor equivalence ratio nor its residence time was a direct contributor to the exit NO(x). Based on this study, it was also concluded that: (1) While NO(x) formation in both the mixing section and the lean combustor contribute to the overall emission, the NOx formation in the mixing section dominates. The gas composition exiting the rich combustor can be reasonably represented by the equilibrium composition corresponding to the rich combustor operating condition. Negligible NO(x) exits the rich combustor. (2) At the SSC condition, the oxidation processes occurring in the mixing section consume 99 percent of the CO exiting the rich combustor. Soot formed in the rich combustor is also highly oxidized, with combustor exit SAE Smoke Number <3. (3) Mixing section configurations which demonstrated enhanced emissions control at SSC also performed better at part-power conditions. Data from mixer exit traverses reflected the expected mixing behavior for off-design jet to crossflow momentum-flux ratios. (4) Low power operating conditions require that the RQL combustor operate as a lean-lean combustor to achieve low CO and high efficiency. (5) An RQL combustor can achieve the emissions goal of EINO(x) = 5 at the Supersonic Cruise operating condition for an HSCT engine.
Reusable Launch Vehicle Control in Multiple Time Scale Sliding Modes
NASA Technical Reports Server (NTRS)
Shtessel, Yuri
1999-01-01
A reusable launch vehicle control problem during ascent is addressed via multiple-time scaled continuous sliding mode control. The proposed sliding mode controller utilizes a two-loop structure and provides robust, de-coupled tracking of both orientation angle command profiles and angular rate command profiles in the presence of bounded external disturbances and plant uncertainties. Sliding mode control causes the angular rate and orientation angle tracking error dynamics to be constrained to linear, de-coupled, homogeneous, and vector valued differential equations with desired eigenvalues placement. The dual-time scale sliding mode controller was designed for the X-33 technology demonstration sub-orbital launch vehicle in the launch mode. 6DOF simulation results show that the designed controller provides robust, accurate, de-coupled tracking of the orientation angle command profiles in presence of external disturbances and vehicle inertia uncertainties. It creates possibility to operate the X-33 vehicle in an aircraft-like mode with reduced pre-launch adjustment of the control system.
An electric propulsion long term test facility
NASA Technical Reports Server (NTRS)
Trump, G.; James, E.; Vetrone, R.; Bechtel, R.
1979-01-01
An existing test facility was modified to provide for extended testing of multiple electric propulsion thruster subsystems. A program to document thruster subsystem characteristics as a function of time is currently in progress. The facility is capable of simultaneously operating three 2.7-kW, 30-cm mercury ion thrusters and their power processing units. Each thruster is installed via a separate air lock so that it can be extended into the 7m x 10m main chamber without violating vacuum integrity. The thrusters exhaust into a 3m x 5m frozen mercury target. An array of cryopanels collect sputtered target material. Power processor units are tested in an adjacent 1.5m x 2m vacuum chamber or accompanying forced convection enclosure. The thruster subsystems and the test facility are designed for automatic unattended operation with thruster operation computer controlled. Test data are recorded by a central data collection system scanning 200 channels of data a second every two minutes. Results of the Systems Demonstration Test, a short shakedown test of 500 hours, and facility performance during the first year of testing are presented.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Masuda, Takuya; PRESTO, Japan Science and Technology Agency; Yoshikawa, Hideki
In situ electrochemical X-ray photoelectron spectroscopy (XPS) apparatus, which allows XPS at solid/liquid interfaces under potential control, was constructed utilizing a microcell with an ultra-thin Si membrane, which separates vacuum and a solution. Hard X-rays from a synchrotron source penetrate into the Si membrane surface exposed to the solution. Electrons emitted at the Si/solution interface can pass through the membrane and be analyzed by an analyzer placed in vacuum. Its operation was demonstrated for potential-induced Si oxide growth in water. Effect of potential and time on the thickness of Si and Si oxide layers was quantitatively determined at sub-nanometer resolution.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kirby J. Baumgard; Richard E. Winsor
2009-12-31
The objectives of the reported work were: to apply the stoichiometric compression ignition (SCI) concept to a 9.0 liter diesel engine; to obtain engine-out NO{sub x} and PM exhaust emissions so that the engine can meet 2010 on-highway emission standards by applying a three-way catalyst for NO{sub x} control and a particulate filter for PM control; and to simulate an optimize the engine and air system to approach 50% thermal efficiency using variable valve actuation and electric turbo compounding. The work demonstrated that an advanced diesel engine can be operated at stoichiometric conditions with reasonable particulate and NOx emissions atmore » full power and peak torque conditions; calculated that the SCI engine will operate at 42% brake thermal efficiency without advanced hardware, turbocompounding, or waste heat recovery; and determined that EGR is not necessary for this advanced concept engine, and this greatly simplifies the concept.« less
SpaceX Falcon Heavy Demo Flight - Press Site Activities
2018-02-06
Members of the news media begin setting up at the NASA News Center to await liftoff of the SpaceX Falcon Heavy rocket from Launch Complex 39A at Kennedy Space Center in Florida. The iconic Vehicle Assembly Building and Launch Control Center are visible in the background. The Falcon Heavy demonstration flight will be a significant milestone for the world's premier multi-user spaceport. In 2014, NASA signed a property agreement with SpaceX for the use and operation of the center's pad 39A, where the company has launched Falcon 9 rockets and is preparing for the first Falcon Heavy. NASA also has Space Act Agreements in place with partners, such as SpaceX, to provide services needed to process and launch rockets and spacecraft.
The Ftx Noncoding Locus Controls X Chromosome Inactivation Independently of Its RNA Products.
Furlan, Giulia; Gutierrez Hernandez, Nancy; Huret, Christophe; Galupa, Rafael; van Bemmel, Joke Gerarda; Romito, Antonio; Heard, Edith; Morey, Céline; Rougeulle, Claire
2018-05-03
Accumulation of the Xist long noncoding RNA (lncRNA) on one X chromosome is the trigger for X chromosome inactivation (XCI) in female mammals. Xist expression, which needs to be tightly controlled, involves a cis-acting region, the X-inactivation center (Xic), containing many lncRNA genes that evolved concomitantly to Xist from protein-coding ancestors through pseudogeneization and loss of coding potential. Here, we uncover an essential role for the Xic-linked noncoding gene Ftx in the regulation of Xist expression. We show that Ftx is required in cis to promote Xist transcriptional activation and establishment of XCI. Importantly, we demonstrate that this function depends on Ftx transcription and not on the RNA products. Our findings illustrate the multiplicity of layers operating in the establishment of XCI and highlight the diversity in the modus operandi of the noncoding players. Copyright © 2018 Elsevier Inc. All rights reserved.
X-34 Main Propulsion System Design and Operation
NASA Technical Reports Server (NTRS)
Champion, R. J., Jr.; Darrow, R. J., Jr.
1998-01-01
The X-34 program is a joint industry/government program to develop, test, and operate a small, fully-reusable hypersonic flight vehicle, utilizing technologies and operating concepts applicable to future Reusable Launch Vehicle (RLV) systems. The vehicle will be capable of Mach 8 flight to 250,000 feet altitude and will demonstrate an all composite structure, composite RP-1 tank, the Marshall Space Flight Center (MSFC) developed Fastrac engine, and the operability of an advanced thermal protection systems. The vehicle will also be capable of carrying flight experiments. MSFC is supporting the X-34 program in three ways: Program Management, the Fastrac engine as Government Furnished Equipment (GFE), and the design of the Main Propulsion System (MPS). The MPS Product Development Team (PDT) at MSFC is responsible for supplying the MPS design, analysis, and drawings to Orbital. The MPS consists of the LOX and RP-1 Fill, Drain, Feed, Vent, & Dump systems and the Helium & Nitrogen Purge, Pressurization, and Pneumatics systems. The Reaction Control System (RCS) design was done by Orbital. Orbital is the prime contractor and has responsibility for integration, procurement, and construction of all subsystems. The paper also discusses the design, operation, management, requirements, trades studies, schedule, and lessons learning with the MPS and RCS designs.
Reusable Launch Vehicle Technology Program
NASA Technical Reports Server (NTRS)
Freeman, Delma C., Jr.; Talay, Theodore A.; Austin, R. Eugene
1996-01-01
Industry/NASA Reusable Launch Vehicle (RLV) Technology Program efforts are underway to design, test, and develop technologies and concepts for viable commercial launch systems that also satisfy national needs at acceptable recurring costs. Significant progress has been made in understanding the technical challenges of fully reusable launch systems and the accompanying management and operational approaches for achieving a low-cost program. This paper reviews the current status of the Reusable Launch Vehicle Technology Program including the DC-XA, X-33 and X-34 flight systems and associated technology programs. It addresses the specific technologies being tested that address the technical and operability challenges of reusable launch systems including reusable cryogenic propellant tanks, composite structures, thermal protection systems, improved propulsion, and subsystem operability enhancements. The recently concluded DC-XA test program demonstrated some of these technologies in ground and flight tests. Contracts were awarded recently for both the X-33 and X-34 flight demonstrator systems. The Orbital Sciences Corporation X-34 flight test vehicle will demonstrate an air-launched reusable vehicle capable of flight to speeds of Mach 8. The Lockheed-Martin X-33 flight test vehicle will expand the test envelope for critical technologies to flight speeds of Mach 15. A propulsion program to test the X-33 linear aerospike rocket engine using a NASA SR-71 high speed aircraft as a test bed is also discussed. The paper also describes the management and operational approaches that address the challenge of new cost-effective, reusable launch vehicle systems.
Resistive switching phenomena of tungsten nitride thin films with excellent CMOS compatibility
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hong, Seok Man; Kim, Hee-Dong; An, Ho-Myoung
2013-12-15
Graphical abstract: - Highlights: • The resistive switching characteristics of WN{sub x} thin films. • Excellent CMOS compatibility WN{sub x} films as a resistive switching material. • Resistive switching mechanism revealed trap-controlled space charge limited conduction. • Good endurance and retention properties over 10{sup 5} cycles, and 10{sup 5} s, respectively - Abstract: We report the resistive switching (RS) characteristics of tungsten nitride (WN{sub x}) thin films with excellent complementary metal-oxide-semiconductor (CMOS) compatibility. A Ti/WN{sub x}/Pt memory cell clearly shows bipolar RS behaviors at a low voltage of approximately ±2.2 V. The dominant conduction mechanisms at low and high resistancemore » states were verified by Ohmic behavior and trap-controlled space-charge-limited conduction, respectively. A conducting filament model by a redox reaction explains the RS behavior in WN{sub x} films. We also demonstrate the memory characteristics during pulse operation, including a high endurance over >10{sup 5} cycles and a long retention time of >10{sup 5} s.« less
Non-OEM experience with NOx reduction applications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Birchett, K.S.; Chung, L.; Caldwell, R.E.
1996-01-01
Heightened global environmental awareness and mandated deadlines for emission compliance required by the Clean Air Act, demand operators to increase controls on boiler emissions. For decades, the utility boiler industry has been dominated by the large OEM`s. In the past, boiler owners would approach the company that originally designed the boiler or burner system to design a burner system to reduce emissions. It was commonly believed that the boiler manufacturer had the greatest expertise in the area of NO{sub x} reduction. Current experience demonstrates that boiler owners are accepting new approaches to reducing NO{sub x} from non-OEM designers and suppliers.more » This paper outlines new approaches being applied by boiler operators to reduce NO{sub x} emissions. Several steps are imperative for a successful NO{sub x} reduction program and each step of this process will be described with examples presented. Concepts that will be examined are: (1) Practical designing concerns of theoretical Low NO{sub x} combustion, (2) Reviewing scope requirements required to reduce emissions, and (3) Teaming with the Customer to facilitate retrofit design and installation. The emphasis of this paper is not directed at the theory of how the components reduce NO{sub x}, but how to effectively apply proven technology that reduced NO{sub x} emissions.« less
Design and characterization of dielectric subwavelength focusing lens with polarization dependence
NASA Astrophysics Data System (ADS)
Kim, Sung W.; Pang, Lin; Fainman, Yeshaiahu
2016-03-01
We introduce and develop design, fabrication and characterization methodology for engineering the effective refractive index of a composite dielectric planar surface created by controlling the density of deeply subwavelength low index nanoholes (e.g., air) in a high index dielectric layer (e.g., Si). The nanoscale properties of a composite dielectric layer allows for full control of the optical wavefront phase by designing arbitrary space-variant refractive index profiles. We present the composite dielectric metasurface microlens exploiting symmetric design to achieve polarization invariant impulse response, and use asymmetric design to demonstrate polarization sensitive impulse response of the lens. This composite dielectric layers lenses were fabricated by patterning nanohole distributions on a dielectric surface and etching to submicron depths. Our dielectric microlens with asymmetric distribution of neff (neff x ≠ neff y) demonstrates a graded index lens with polarization dependent focusing with of 32um and 22 um for linearly x- and y-polarized light, respectively operating at a wavelength of λ = 1550nm. We also show numerically and demonstrate experimentally achromatic performance of the devices operating in the wavelength range of 1500nm - 1900nm with FWHM of the focal spots of about 4um. Namely, we have constructed a graded index lens that can overcome diffraction effects even when aperture/wavelength (D/λ) is smaller than 40. The demonstrated novel approach to engineer dielectric composite nanosurfaces has the potential to realize arbitrary phase functions with minimal insertion loss, submicron thickness and miniaturization to reduce element size and weight, and may have a significant impact on numerous miniature imaging systems applications.
Flight Control Laws for NASA's Hyper-X Research Vehicle
NASA Technical Reports Server (NTRS)
Davidson, J.; Lallman, F.; McMinn, J. D.; Martin, J.; Pahle, J.; Stephenson, M.; Selmon, J.; Bose, D.
1999-01-01
The goal of the Hyper-X program is to demonstrate and validate technology for design and performance predictions of hypersonic aircraft with an airframe-integrated supersonic-combustion ramjet propulsion system. Accomplishing this goal requires flight demonstration of a hydrogen-fueled scramjet powered hypersonic aircraft. A key enabling technology for this flight demonstration is flight controls. Closed-loop flight control is required to enable a successful stage separation, to achieve and maintain the design condition during the engine test, and to provide a controlled descent. Before the contract award, NASA developed preliminary flight control laws for the Hyper-X to evaluate the feasibility of the proposed scramjet test sequence and descent trajectory. After the contract award, a Boeing/NASA partnership worked to develop the current control laws. This paper presents a description of the Hyper-X Research Vehicle control law architectures with performance and robustness analyses. Assessments of simulated flight trajectories and stability margin analyses demonstrate that these control laws meet the flight test requirements.
NASA Astrophysics Data System (ADS)
Höhnle, H.; Stober, J.; Herrmann, A.; Kasparek, W.; Leuterer, F.; Monaco, F.; Neu, R.; Schmid-Lorch, D.; Schütz, H.; Schweinzer, J.; Stroth, U.; Wagner, D.; Vorbrugg, S.; Wolfrum, E.; ASDEX Upgrade Team
2011-08-01
ASDEX Upgrade has been operated with tungsten-coated plasma-facing components for several years. H-mode operation with good confinement has been demonstrated. Nevertheless, purely neutral beam injection-heated H-modes with reduced gas puff, moderate heating power or/and increased triangularity tend to accumulate tungsten, followed by a radiative collapse. Under these conditions, central electron heating with electron cyclotron resonance heating (ECRH), usually in X2 polarization, changes the impurity transport in the plasma centre, reducing the central tungsten concentration and, in many cases, stabilizing the plasma. In order to extend the applicability of central ECRH to a wider range of magnetic field and plasma current additional ECRH schemes with reduced single-pass absorption have been implemented: X3 heating allows us to reduce the magnetic field by 30%, such that the first H-modes with an ITER-like value of the safety factor of q95 = 3 could be run in the tungsten-coated device. O2 heating increases the cutoff density by a factor of 2 allowing higher currents and triangularities to be addressed. For both schemes, scenarios have been developed to cope with the associated reduced absorption. In the case of central X3 heating, the X2 resonance lies close to the pedestal top at the high-field side of the plasma, serving as a beam dump. For O2, holographic mirrors have been developed which guarantee a second pass through the plasma centre. The beam position on these reflectors is controlled by fast thermocouples. Stray-radiation protection has been implemented using sniffer probes.
Development and Operation of Arrays of TES x-ray Microcalorimeters Suitable for Constellation-X
NASA Technical Reports Server (NTRS)
Kilbourne, C. A.; Bandler, S. R.; Brown, A. D.; Chervenak, J. A.; Eckart, M. E.; Finkbeiner, F. M.; Iyomoto, N.; Kelley, R. L.; Porter, F. S.; Smith, S. J.;
2008-01-01
Having already developed a transition-edge-sensor (TES) microcalorimeter design that enables uniform and reproducible high spectral resolution (routinely better than 3 eV resolution at 6 keV) and is compatible with high fill-factor arrays, we are now working towards demonstrating this performance at high count rates and with the multiplexed read-out needed for instrumenting the Constellation-X X-ray Microcalorimeter Spectrometer (XMS) focal plane array. Design changes that increase the speed of the individual XMS pixels, such as lowering the heat capacity or increasing the thermal conductance of the link to the 50-mK heatsink, result in larger, faster signals, thus the coupling to the multiplexer and the overall bandwidth of the electronics must accommodate this increase in slew rate. In order to operate the array with high incident x-ray flux without unacceptable degradation of the spectral resolution, the magnitude of thermal and electrical crosstalk must be controlled. We will discuss recent progress in the thermal and electrical designs of our close-packed TES arrays, and we will present spectra acquired through the read-out chain from the multiplexer electronics, through the demultiplexer software, to real-time signal processing.
Development of Fe-based superconducting wires for liquid-hydrogen level sensors
NASA Astrophysics Data System (ADS)
Ishida, S.; Tsuchiya, Y.; Mawatari, Y.; Eisaki, H.; Nakano, A.; Yoshida, Y.
2017-07-01
We developed liquid-hydrogen (LH2) level sensors with Ba(Fe1-x Co x )2As2 superconducting wires (Co-Ba122 wires) as their detection elements. We fabricated Co-Ba122 wires with different Co concentrations x by using the powder-in-tube method. The superconducting transition temperatures of the wires were successfully controlled in the range of 20-25 K by changing x from 0.06 to 0.10. The resistance-temperature curves of the wires exhibited sharp superconducting transitions with widths of 0.5-1.0 K. In addition, we performed an operation test of the Co-Ba122 level sensors with LH2. Close correspondence between the output resistance and the actual LH2 level was observed for a sensor equipped with x = 0.09 wire, demonstrating that this sensor can accurately measure LH2 levels.
Forsberg, J; Englund, C-J; Duda, L-C
2009-08-01
We present the design and operation of a versatile soft X-ray transmission system for time resolved in situ microscopy with chemical contrast. The utility of the setup is demonstrated by results from following a corrosion process of iron in saline environment, subjected to a controlled humid atmosphere. The system includes a transmission flow-cell reactor that allows for in situ microscopic probing with soft X-rays. We employ a full field technique by using a nearly collimated X-ray beam that produces an unmagnified projection of the transmitted soft X-rays (below 1.1 keV) which is magnified and recorded by an optical CCD camera. Time lapse series with chemical contrast allow us to follow and interpret the chemical processes in detail. The obtainable lateral resolution is a few mum, sufficient to detect filiform corrosion on iron.
NASA Technical Reports Server (NTRS)
1995-01-01
The X-31 Enhanced Fighter Maneuverability Technology Demonstrator Aircraft, based at the NASA Dryden Flight Research Center, Edwards Air Force Base, California, is secured inside the fuselage of an Air Force Reserve C-5 transport. The C-5 was used to ferry the X-31 from Europe back to Edwards, after being flown in the Paris Air Show in June 1995. The X-31's right wing, removed so the aircraft could fit inside the C-5, is in the shipping container in the foreground. At the air show, the X-31 demonstrated the value of using thrust vectoring (directing engine exhaust flow) coupled with advanced flight control systems to provide controlled flight at very high angles of attack. The X-31 Enhanced Fighter Maneuverability (EFM) demonstrator flew at the Ames- Dryden Flight Research Facility, Edwards, California (redesignated the Dryden Flight Research Center in 1994) from February 1992 until 1995 and before that at the Air Force's Plant 42 in Palmdale, California. The goal of the project was to provide design information for the next generation of highly maneuverable fighter aircraft. This program demonstrated the value of using thrust vectoring (directing engine exhaust flow) coupled with an advanced flight control system to provide controlled flight to very high angles of attack. The result was a significant advantage over most conventional fighters in close-in combat situations. The X-31 flight program focused on agile flight within the post-stall regime, producing technical data to give aircraft designers a better understanding of aerodynamics, effectiveness of flight controls and thrust vectoring, and airflow phenomena at high angles of attack. Stall is a condition of an airplane or an airfoil in which lift decreases and drag increases due to the separation of airflow. Thrust vectoring compensates for the loss of control through normal aerodynamic surfaces that occurs during a stall. Post-stall refers to flying beyond the normal stall angle of attack, which in the X-31 was at a 30-degree angle of attack. During Dryden flight testing, the X-31 aircraft established several milestones. On November 6, 1992, the X-31 achieved controlled flight at a 70-degree angle of attack. On April 29, 1993, the second X-31 successfully executed a rapid minimum-radius, 180-degree turn using a post-stall maneuver, flying well beyond the aerodynamic limits of any conventional aircraft. This revolutionary maneuver has been called the 'Herbst Maneuver' after Wolfgang Herbst, a German proponent of using post-stall flight in air-to-air combat. It is also called a 'J Turn' when flown to an arbitrary heading change. The aircraft was flown in tactical maneuvers against an F/A-18 and other tactical aircraft as part of the test flight program. During November and December 1993, the X-31 reached a supersonic speed of Mach 1.28. In 1994, the X-31 program installed software to demonstrate quasi-tailless operation. The X-31 flight test program was conducted by an international test organization (ITO) managed by the Advanced Research Projects Office (ARPA), known as the Defense Advanced Research Projects Office (DARPA) before March 1993. The ITO included the U.S. Navy and U.S. Air Force, Rockwell Aerospace, the Federal Republic of Germany, Daimler-Benz (formerly Messerschmitt-Bolkow-Blohm and Deutsche Aerospace), and NASA. Gary Trippensee was the ITO director and NASA Project Manager. Pilots came from participating organizations. The X-31 was 43.33 feet long with a wingspan of 23.83 feet. It was powered by a single General Electric P404-GE-400 turbofan engine that produced 16,000 pounds of thrust in afterburner.
X-33 Ascent Flight Controller Design by Trajectory Linearization: A Singular Perturbational Approach
NASA Technical Reports Server (NTRS)
Zhu, J. Jim; Banker, Brad D.; Hall, Charles E.
2000-01-01
The flight control of X-33 poses a challenge to conventional gain-scheduled flight controllers due to its large attitude maneuvers from liftoff to orbit and reentry. In addition, a wide range of uncertainties in vehicle handling qualities and disturbances must be accommodated by the attitude control system. Nonlinear tracking and decoupling control by trajectory linearization can be viewed as the ideal gain-scheduling controller designed at every point on the flight trajectory. Therefore it provides robust stability and performance at all stages of flight without interpolation of controller gains and eliminates costly controller redesigns due to minor airframe alteration or mission reconfiguration. In this paper, a prototype trajectory linearization design for an X-33 ascent flight controller is presented along with 3-DOF and 6-DOF simulation results. It is noted that the 6-DOF results were obtained from the 3-DOF design with only a few hours of tuning, which demonstrates the inherent robustness of the design technique. It is this "plug-and-play" feature that is much needed by NASA for the development, test and routine operations of the RLV'S. Plans for further research are also presented, and refined 6-DOF simulation results will be presented in the final version of the paper.
Air Traffic Control and Combat Control Team Operations, AFS 272X0/D.
1980-12-01
LN4LASSIFXED DE 8.NuAD.___ UNITED STATES AIR FORCE A-’IR TRAFFIC CONTROL AND COMBAT/ . _ ) ~E: ;ONTROLIEAM OPERATIONS E’.. . --.ET E AFS 272xG/D,) O...Occupational Measurement Center, Randolph AFB, Texas 78148. Computer programs for analyzing the occupational data were designed by Dr. Raymond E...remained relatively the same in terms of numerical designation and tasks performed. Formal training for both 272X0 and 272XOD entry-level personnel consists
2004-01-24
Engineers and technicians in the control room at the Dryden Flight Research Center must constantly monitor critical operations and checks during research projects like NASA's hypersonic X-43A. Visible in the photo, taken two days before the X-43's captive carry flight in January 2004, are [foreground to background]; Tony Kawano (Range Safety Officer), Brad Neal (Mission Controller), and Griffin Corpening (Test Conductor).
NASA Astrophysics Data System (ADS)
Marukame, Takao; Nishi, Yoshifumi; Yasuda, Shin-ichi; Tanamoto, Tetsufumi
2018-04-01
The use of memristive devices for creating artificial neurons is promising for brain-inspired computing from the viewpoints of computation architecture and learning protocol. We present an energy-efficient multiplier accumulator based on a memristive array architecture incorporating both analog and digital circuitries. The analog circuitry is used to full advantage for neural networks, as demonstrated by the spike-timing-dependent plasticity (STDP) in fabricated AlO x /TiO x -based metal-oxide memristive devices. STDP protocols for controlling periodic analog resistance with long-range stability were experimentally verified using a variety of voltage amplitudes and spike timings.
The Set of Diagnostics for the First Operation Campaign of the Wendelstein 7-X Stellarator
NASA Astrophysics Data System (ADS)
König, Ralf; Baldzuhn, J.; Biel, W.; Biedermann, C.; Bosch, H. S.; Bozhenkov, S.; Bräuer, T.; Brotas de Carvalho, B.; Burhenn, R.; Buttenschön, B.; Cseh, G.; Czarnecka, A.; Endler, M.; Erckmann, V.; Estrada, T.; Geiger, J.; Grulke, O.; Hartmann, D.; Hathiramani, D.; Hirsch, M.; Jabłonski, S.; Jakubowski, M.; Kaczmarczyk, J.; Klinger, T.; Klose, S.; Kocsis, G.; Kornejew, P.; Krämer-Flecken, A.; Kremeyer, T.; Krychowiak, M.; Kubkowska, M.; Langenberg, A.; Laqua, H. P.; Laux, M.; Liang, Y.; Lorenz, A.; Marchuk, A. O.; Moncada, V.; Neubauer, O.; Neuner, U.; Oosterbeek, J. W.; Otte, M.; Pablant, N.; Pasch, E.; Pedersen, T. S.; Rahbarnia, K.; Ryc, L.; Schmitz, O.; Schneider, W.; Schuhmacher, H.; Schweer, B.; Stange, T.; Thomsen, H.; Travere, J.-M.; Szepesi, T.; Wenzel, U.; Werner, A.; Wiegel, B.; Windisch, T.; Wolf, R.; Wurden, G. A.; Zhang, D.; Zimbal, A.; Zoletnik, S.; the W7-X Team
2015-10-01
Wendelstein 7-X (W7-X) is a large optimized stellarator (B=2.5T, V=30m3) aiming at demonstrating the reactor relevance of the optimized stellarators. In 2015 W7-X will begin its first operation phase (OP1.1) with five inertially cooled inboard limiters made of graphite. Assuming the heat loads can be spread out evenly between the limiters, 1 second discharges at 2 MW of ECRH heating power could be run in OP1.1. The expected plasma parameters will be sufficient to demonstrate the readiness of the installed diagnostics and even to run a first physics program. The diagnostics available for this first operation phase, including some special limiter diagnostics, and their capabilities are being presented. A shorter version of this contribution is due to be published in PoS at: 1st EPS conference on Plasma Diagnostics
Two-bunch operation with ns temporal separation at the FERMI FEL facility
NASA Astrophysics Data System (ADS)
Penco, Giuseppe; Allaria, Enrico; Bassanese, Silvano; Cinquegrana, Paolo; Cleva, Stefano; Danailov, Miltcho B.; Demidovich, Alexander; Ferianis, Mario; Gaio, Giulio; Giannessi, Luca; Masciovecchio, Claudio; Predonzani, Mauro; Rossi, Fabio; Roussel, Eleonore; Spampinati, Simone; Trovò, Mauro
2018-05-01
In the last decade, a continuous effort has been dedicated to extending the capabilities of existing free-electron lasers (FELs) operating in the x-ray and vacuum ultraviolet regimes. In this framework, the generation of two-color (or multi-color) temporally separated FEL pulses, has paved the way to new x-ray pump and probe experiments and several two-color two-pulse schemes have been implemented at the main facilities, but with a generally limited time-separation between the pulses, from 0 to few hundreds of fs. This limitation may be overcome by generating light with two independent electron bunches, temporally separated by integral multiples of the radio-frequency period. This solution was investigated at FERMI, measurements and characterization of this two-bunch mode of operation are presented, including trajectory control, impact of longitudinal and transverse wakefields, manipulation of the longitudinal phase space and finally a demonstration of suitability of the scheme to provide extreme ultraviolet light by using both bunches.
Study of dynamics of X-14B VTOL aircraft
NASA Technical Reports Server (NTRS)
Loscutoff, W. V.; Mitchiner, J. L.; Roesener, R. A.; Seevers, J. A.
1973-01-01
Research was initiated to investigate certain facets of modern control theory and their integration with a digital computer to provide a tractable flight control system for a VTOL aircraft. Since the hover mode is the most demanding phase in the operation of a VTOL aircraft, the research efforts were concentrated in this mode of aircraft operation. Research work on three different aspects of the operation of the X-14B VTOL aircraft is discussed. A general theory for optimal, prespecified, closed-loop control is developed. The ultimate goal was optimal decoupling of the modes of the VTOL aircraft to simplify the pilot's task of handling the aircraft. Modern control theory is used to design deterministic state estimators which provide state variables not measured directly, but which are needed for state variable feedback control. The effect of atmospheric turbulence on the X-14B is investigated. A maximum magnitude gust envelope within which the aircraft could operate stably with the available control power is determined.
Operational viewpoint of the X-29A digital flight control system
NASA Technical Reports Server (NTRS)
Chacon, Vince; Mcbride, David
1988-01-01
In the past few years many flight control systems have been implemented as full-authority, full-time digital systems. The digital design has allowed flight control systems to make use of many enhanced elements that are generally considered too complex to implement in an analog system. Examples of these elements are redundant information exchanged between channels to allow for continued operation after multiple failures and multiple variable gain schedules to optimize control of the aircraft throughout its flight envelope and in all flight modes. The introduction of the digital system for flight control also created the problem of obtaining information from the system in an understandable and useful format. This paper presents how the X-29A was dealt with during its operations at NASA Ames-Dryden Flight Research Facility. A brief description of the X-29A control system, a discussion of the tools developed to aid in daily operations, and the troubleshooting of the aircraft are included.
Sextant X-Ray Pulsar Navigation Demonstration: Initial On-Orbit Results
NASA Technical Reports Server (NTRS)
Mitchell, Jason W.; Winternitz, Luke M.; Hassouneh, Munther A.; Price, Samuel R.; Semper, Sean R.; Yu, Wayne H.; Ray, Paul S.; Wolff, Michael T.; Kerr, Matthew; Wood, Kent S.;
2018-01-01
The Station Explorer for X-ray Timing and Navigation Technology (SEXTANT) is a technology demonstration enhancement to the Neutron-star Interior Composition Explorer (NICER) mission. SEXTANT will be a first demonstration of in-space, autonomous, X-ray pulsar navigation (XNAV). Navigating using millisecond X-ray pulsars which could provide a GPS-like navigation capability available throughout our Solar System and beyond. NICER is a NASA Astrophysics Explorer Mission of Opportunity to the International Space Station that was launched and installed in June of 2017. During NICER's nominal 18-month base mission, SEXTANT will perform a number of experiments to demonstrate XNAV and advance the technology on a number of fronts. In this work, we review the SEXTANT, its goals, and present early results from SEXTANT experiments conducted in the first six months of operation. With these results, SEXTANT has made significant progress toward meeting its primary and secondary mission goals. We also describe the SEXTANT flight operations, calibration activities, and initial results.
A compact electroencephalogram recording device with integrated audio stimulation system.
Paukkunen, Antti K O; Kurttio, Anttu A; Leminen, Miika M; Sepponen, Raimo E
2010-06-01
A compact (96 x 128 x 32 mm(3), 374 g), battery-powered, eight-channel electroencephalogram recording device with an integrated audio stimulation system and a wireless interface is presented. The recording device is capable of producing high-quality data, while the operating time is also reasonable for evoked potential studies. The effective measurement resolution is about 4 nV at 200 Hz sample rate, typical noise level is below 0.7 microV(rms) at 0.16-70 Hz, and the estimated operating time is 1.5 h. An embedded audio decoder circuit reads and plays wave sound files stored on a memory card. The activities are controlled by an 8 bit main control unit which allows accurate timing of the stimuli. The interstimulus interval jitter measured is less than 1 ms. Wireless communication is made through bluetooth and the data recorded are transmitted to an external personal computer (PC) interface in real time. The PC interface is implemented with LABVIEW and in addition to data acquisition it also allows online signal processing, data storage, and control of measurement activities such as contact impedance measurement, for example. The practical application of the device is demonstrated in mismatch negativity experiment with three test subjects.
Greenidge Multi-Pollutant Control Project
DOE Office of Scientific and Technical Information (OSTI.GOV)
Connell, Daniel
2008-10-18
The Greenidge Multi-Pollutant Control Project was conducted as part of the U.S. Department of Energy's Power Plant Improvement Initiative to demonstrate an innovative combination of air pollution control technologies that can cost-effectively reduce emissions of SO{sub 2}, NO{sub x}, Hg, acid gases (SO{sub 3}, HCl, and HF), and particulate matter from smaller coal-fired electric generating units (EGUs). There are about 400 units in the United States with capacities of 50-300 MW that currently are not equipped with selective catalytic reduction (SCR), flue gas desulfurization (FGD), or mercury control systems. Many of these units, which collectively represent more than 55 GWmore » of installed capacity, are difficult to retrofit for deep emission reductions because of space constraints and unfavorable economies of scale, making them increasingly vulnerable to retirement or fuel switching in the face of progressively more stringent environmental regulations. The Greenidge Project sought to confirm the commercial readiness of an emissions control system that is specifically designed to meet the environmental compliance requirements of these smaller coal-fired EGUs by offering a combination of deep emission reductions, low capital costs, small space requirements, applicability to high-sulfur coals, mechanical simplicity, and operational flexibility. The multi-pollutant control system includes a NO{sub x}OUT CASCADE{reg_sign} hybrid selective non-catalytic reduction (SNCR)/in-duct SCR system for NO{sub x} control and a Turbosorp{reg_sign} circulating fluidized bed dry scrubbing system (with a new baghouse) for SO{sub 2}, SO{sub 3}, HCl, HF, and particulate matter control. Mercury removal is provided as a co-benefit of the in-duct SCR, dry scrubber, and baghouse, and by injection of activated carbon upstream of the scrubber, if required. The multi-pollutant control system was installed and tested on the 107-MW{sub e}, 1953-vintage AES Greenidge Unit 4 by a team including CONSOL Energy Inc. as prime contractor, AES Greenidge LLC as host site owner, and Babcock Power Environmental Inc. as engineering, procurement, and construction contractor. About 44% of the funding for the project was provided by the U.S. Department of Energy, through its National Energy Technology Laboratory, and the remaining 56% was provided by AES Greenidge. Project goals included reducing high-load NO{sub x} emissions to {le} 0.10 lb/mmBtu; reducing SO{sub 2}, SO{sub 3}, HCl, and HF emissions by at least 95%; and reducing Hg emissions by at least 90% while the unit fired 2-4% sulfur eastern U.S. bituminous coal and co-fired up to 10% biomass. This report details the final results from the project. The multi-pollutant control system was constructed in 2006, with a total plant cost of $349/kW and a footprint of 0.4 acre - both substantially less than would have been required to retrofit AES Greenidge Unit 4 with a conventional SCR and wet scrubber. Start-up of the multi-pollutant control system was completed in March 2007, and the performance of the system was then evaluated over an approximately 18-month period of commercial operation. Guarantee tests conducted in March-June 2007 demonstrated attainment of all of the emission reduction goals listed above. Additional tests completed throughout the performance evaluation period showed 96% SO{sub 2} removal, 98% mercury removal (with no activated carbon injection), 95% SO{sub 3} removal, and 97% HCl removal during longer-term operation. Greater than 95% SO{sub 2} removal efficiency was observed even when the unit fired high-sulfur coals containing up to 4.8 lb SO{sub 2}/mmBtu. Particulate matter emissions were reduced by more than 98% relative to the emission rate observed prior to installation of the technology. The performance of the hybrid SNCR/SCR system was affected by problems with large particle ash, ammonia slip, and nonideal combustion characteristics, and high-load NO{sub x} emissions averaged 0.14 lb/mmBtu during long-term operation. Nevertheless, the system has reduced the unit's overall NO{sub x} emissions by 52% on a lb/mmBtu basis. The commercial viability of the multi-pollutant control system was demonstrated at AES Greenidge Unit 4. The system, which remains in service after the conclusion of the project, has enabled the unit to satisfy its permit requirements while continuing to operate profitably. As a result of the success at AES Greenidge Unit 4, three additional deployments of the Turbosorp{reg_sign} technology had been announced by the end of the project.« less
Zoom system without moving element by using two liquid crystal lenses with spherical electrode
NASA Astrophysics Data System (ADS)
Yang, Ren-Kai; Lin, Chia-Ping; Su, Guo-Dung J.
2017-08-01
A traditional zoom system is composed of several elements moving relatively toward other components to achieve zooming. Unlike tradition system, an electrically control zoom system with liquid crystal (LC) lenses is demonstrated in this paper. To achieve zooming, we apply two LC lenses whose optical power is controlled by voltage to replace two moving lenses in traditional zoom system. The mechanism of zoom system is to use two LC lenses to form a simple zoom system. We found that with such spherical electrodes, we could operate LC lens at voltage range from 31V to 53 V for 3X tunability in optical power. For each LC lens, we use concave spherical electrode which provide lower operating voltage and great tunability in optical power, respectively. For such operating voltage and compact size, this zoom system with zoom ratio approximate 3:1 could be applied to mobile phone, camera and other applications.
X-45A in flight with F-18 #846 chase aircraft, during first GPS-guided weapon demonstration flight
2002-12-19
The first X-45A Unmanned Combat Air Vehicle (UCAV) technology demonstrator completed its sixth flight on Dec. 19, 2002, raising its landing gear in flight for the first time. The X-45A flew for 40 minutes and reached an airspeed of 195 knots and an altitude of 7,500 feet. Dryden is supporting the DARPA/Boeing team in the design, development, integration, and demonstration of the critical technologies, processes, and system attributes leading to an operational UCAV system. Dryden support of the X-45A demonstrator system includes analysis, component development, simulations, ground and flight tests.
Computer graphic of Lockheed Martin X-33 Reusable Launch Vehicle (RLV) mounted on NASA 747 ferry air
NASA Technical Reports Server (NTRS)
1997-01-01
This is an artist's conception of the NASA/Lockheed Martin X-33 Advanced Technology Demonstrator being carried on the back of the 747 Shuttle Carrier Aircraft. This was a concept for moving the X-33 from its landing site back to NASA's Dryden Flight Research Center, Edwards, California. The X-33 was a technology demonstrator vehicle for the Reusable Launch Vehicle (RLV). The RLV technology program was a cooperative agreement between NASA and industry. The goal of the RLV technology program was to enable significant reductions in the cost of access to space, and to promote the creation and delivery of new space services and other activities that will improve U.S. economic competitiveness. NASA Headquarter's Office of Space Access and Technology oversaw the RLV program, which was being managed by the RLV Office at NASA's Marshall Space Flight Center, located in Huntsville, Alabama. Responsibilities of other NASA Centers included: Johnson Space Center, Houston, Texas, guidance navigation and control technology, manned space systems, and health technology; Ames Research Center, Mountain View, CA., thermal protection system testing; Langley Research Center, Langley, Virginia, wind tunnel testing and aerodynamic analysis; and Kennedy Space Center, Florida, RLV operations and health management. Lockheed Martin's industry partners in the X-33 program are: Astronautics, Inc., Denver, Colorado, and Huntsville, Alabama; Engineering & Science Services, Houston, Texas; Manned Space Systems, New Orleans, LA; Sanders, Nashua, NH; and Space Operations, Titusville, Florida. Other industry partners are: Rocketdyne, Canoga Park, California; Allied Signal Aerospace, Teterboro, NJ; Rohr, Inc., Chula Vista, California; and Sverdrup Inc., St. Louis, Missouri.
Evaluation of Various Navigation System Concepts
1982-03-01
Naigatimon aar01 N DAutomatic x xx Parallel 0fn x x x x x’ "OLeg t dung. n Mrankuhld M ni raia x N x to~g TAN is I OmuI,2 2mN 0 x "to - - -x...and must permit design of indicators and controls which can be directly interpreted or operated by the pilot at his normal station aboard the...the responsibility of control. The organization that controls the system can theoretically limit access to the system. Because VOVO/DME, Loran-C, and
[The study of DSX-I type microcomputer autometic control injector system].
Shi, M; Wu, G; Bai, G; Xue, J; Zhang, Y
1997-01-01
This paper studies the propulsive force of injector system controlled by 8031 single-chip microcomputer for Medical use By using one 8031 single-chip microcomputer as a microprocessor, the minimal autometic control system is constructed, which turns real-time control into reality. This product is a modern appliance used in diagnostic imaging medicine, in design of which the advanced instrument and electrical machinery are integrated into a unified structure. The clinic data demonstrate that the contrast medium can be injected to patients with rapidly and evenly. Dynamic CT Scanning can be intensified at any site of the body. x-ray dose exposed and lobour intensity to the operator can be decreased greatly, raise working efficiency.
Styles, Mark J; Rowles, Matthew R; Madsen, Ian C; McGregor, Katherine; Urban, Andrew J; Snook, Graeme A; Scarlett, Nicola V Y; Riley, Daniel P
2012-01-01
This paper describes the design, construction and implementation of a relatively large controlled-atmosphere cell and furnace arrangement. The purpose of this equipment is to facilitate the in situ characterization of materials used in molten salt electrowinning cells, using high-energy X-ray scattering techniques such as synchrotron-based energy-dispersive X-ray diffraction. The applicability of this equipment is demonstrated by quantitative measurements of the phase composition of a model inert anode material, which were taken during an in situ study of an operational Fray-Farthing-Chen Cambridge electrowinning cell, featuring molten CaCl(2) as the electrolyte. The feasibility of adapting the cell design to investigate materials in other high-temperature environments is also discussed.
X-31 in flight, Herbst maneuver
NASA Technical Reports Server (NTRS)
1990-01-01
Two X-31 Enhanced Fighter Maneuverability (EFM) demonstrators were flown at the Rockwell International Palmdale, California, facility and the NASA Dryden Flight Research Center, Edwards, California, to obtain data that may apply to the design of highly-maneuverable next-generation fighters. The program had its first flight on October 11, 1990, in Palmdale; it ended in June 1995. The X-31 program demonstrated the value of thrust vectoring (directing engine exhaust flow) coupled with advanced flight control systems, to provide controlled flight during close-in air combat at very high angles of attack. The result of this increased maneuverability is an aircraft with a significant advantage over conventional fighters. 'Angle-of-attack' (alpha) is an engineering term to describe the angle of an aircraft body and wings relative to its actual flight path. During maneuvers, pilots often fly at extreme angles of attack--with the nose pitched up while the aircraft continues in its original direction. This can lead to loss of control and result in the loss of the aircraft, or both. Three thrust-vectoring paddles made of graphite epoxy mounted on the X-31 aircraft exhaust nozzle directed the exhaust flow to provide control in pitch (up and down) and yaw (right and left) to improve control. The paddles can sustain heat of up to 1,500 degrees centigrade for extended periods of time. In addition the X-31 aircraft were configured with movable forward canards and fixed aft strakes. The canards were small wing-like structures set on the wing line between the nose and the leading edge of the wing. The strakes were set on the same line between the trailing edge of the wing and the engine exhaust. Both supplied additional control in tight maneuvering situations. The X-31 research program produced technical data at high angles of attack. This information is giving engineers and aircraft designers a better understanding of aerodynamics, effectiveness of flight controls and thrust vectoring, and airflow phenomena at high angles of attack. This is expected to lead to design methods that provide better maneuverability in future high performance aircraft and make them safer to fly. An international test organization of about 110 people, managed by the Advanced Research Projects Agency (ARPA), conducted the flight operations at NASA Dryden. The ARPA had requested flight research for the X-31 aircraft be moved there in February 1992. In addition to ARPA and NASA, the International Test Organization (ITO) included the U.S. Navy, the U.S. Air Force, Rockwell International, the Federal Republic of Germany, and Daimler-Benz Aerospace (formerly Messerschmitt-Bolkow-Blohm and Deutsche Aerospace). NASA was responsible for flight research operations, aircraft maintenance, and research engineering once the program moved to Dryden. The No. 1 X-31 aircraft was lost in an accident Jan. 19, 1995. The pilot, Karl Heinz-Lang, of the Federal Republic of Germany, ejected safely before the aircraft crashed in an unpopulated desert area just north of Edwards. The X-31 program logged an X-plane record of 580 flights during the program, including 555 research missions and 21 in Europe for the 1995 Paris Air Show. A total of 14 pilots representing all agencies of the ITO flew the aircraft. In this 40-second movie clip the X-31 aircraft is shown performing the 'Herbst maneuver,' which is a rapid, minimum-180-degree turn using a post-stall maneuver flying well beyond the aerodynamic limits of any conventional aircraft. Named after Wolfgang Herbst a proponent of using post-stall flight in air-to-air combat.
X-31 in flight - Double Reversal
NASA Technical Reports Server (NTRS)
1995-01-01
Two X-31 Enhanced Fighter Maneuverability (EFM) demonstrators were flown at the Rockwell International facility, Palmdale, California, and the NASA Dryden Flight Research Center, Edwards, California, to obtain data that may apply to the design of highly-maneuverable next-generation fighters. The program had its first flight on October 11, 1990, in Palmdale; it ended in June 1995. The X-31 program demonstrated the value of thrust vectoring (directing engine exhaust flow) coupled with advanced flight control systems, to provide controlled flight during close-in air combat at very high angles of attack. The result of this increased maneuverability is an airplane with a significant advantage over conventional fighters. 'Angle-of-attack' (alpha) is an engineering term to describe the angle of an aircraft body and wings relative to its actual flight path. During maneuvers, pilots often fly at extreme angles of attack -- with the nose pitched up while he aircraft continues in its original direction. This can lead to loss of control and result in the loss of the aircraft, pilot or both. Three thrust-vectoring paddles made of graphite epoxy mounted on the exhaust nozzle of the X-31 aircraft directed the exhaust flow to provide control in pitch (up and down) and yaw (right and left) to improve control. The paddles can sustain heat of up to 1,500 degrees centigrade for extended periods of time. In addition the X-31 aircraft were configured with movable forward canards and fixed aft strakes. The canards were small wing-like structures set on the wing line between the nose and the leading edge of the wing. The strakes were set on the same line between the trailing edge of the wing and the engine exhaust. Both supplied additional control in tight maneuvering situations. The X-31 research program produced technical data at high angles of attack. This information is giving engineers and aircraft designers a better understanding of aerodynamics, effectiveness of flight controls and thrust vectoring, and airflow phenomena at high angles of attack. This understanding is expected to lead to design methods that provide better maneuverability in future high performance aircraft and make them safer to fly. An international test organization of about 110 people, managed by the Advanced Research Projects Agency (ARPA), conducted the flight operations at NASA Dryden. The ARPA had requested flight research for the X-31 aircraft be moved there in February 1992. In addition to ARPA and NASA, the international test organization (ITO) included the U.S. Navy, the U.S. Air Force, Rockwell International, the Federal Republic of Germany, and Daimler-Benz Aerospace (formerly Messerschmitt-Bolkow-Blohm and Deutsche Aerospace). NASA was responsible for flight research operations, aircraft maintenance, and research engineering once the program moved to Dryden. The No. 1 X-31 aircraft was lost in an accident Jan. 19, 1995. The pilot, Karl Heinz-Lang, of the Federal Republic of Germany, ejected safely before the aircraft crashed in an unpopulated desert area just north of Edwards. The X-31 program logged an X-plane record of 580 flights during the program, including 555 research missions and 21 in Europe for the 1995 Paris Air Show. A total of 14 pilots representing all agencies of the ITO flew the aircraft. This 39-second clip begins as the X-31 performs a short loop at the top of a stall maneuver, then quickly reverses its course first left, then right by means of thrust vectoring -- thereby gaining a tactical advantage over a putative opponent in air-to-air combat.
NASA Technical Reports Server (NTRS)
1995-01-01
Two X-31 Enhanced Fighter Maneuverability (EFM) demonstrators were flown at the Rockwell International facility, Palmdale, California, and the NASA Dryden Flight Research Center, Edwards, California, to obtain data that may apply to the design of highly-maneuverable next-generation fighters. The program had its first flight on October 11, 1990, in Palmdale; it ended in June 1995. The X-31 program demonstrated the value of thrust vectoring (directing engine exhaust flow) coupled with advanced flight control systems, to provide controlled flight during close-in air combat at very high angles of attack. The result of this increased maneuverability is an airplane with a significant advantage over conventional fighters. 'Angle-of-attack' (alpha) is an engineering term to describe the angle of an aircraft's body and wings relative to its actual flight path. During maneuvers, pilots often fly at extreme angles of attack -- with the nose pitched up while the aircraft continues in its original direction. This can lead to loss of control and result in the loss of the aircraft, pilot or both. Three thrust vectoring paddles made of graphite epoxy mounted on the exhaust nozzle of the X-31 aircraft directed the exhaust flow to provide control in pitch (up and down) and yaw (right and left) to improve control. The paddles can sustain heat of up to 1,500 degrees centigrade for extended periods of time. In addition the X-31 aircraft were configured with movable forward canards and fixed aft strakes. The canards were small wing-like structures set on the wing line between the nose and the leading edge of the wing. The strakes were set on the same line between the trailing edge of the wing and the engine exhaust. Both supplied additional control in tight maneuvering situations. The X-31 research program produced technical data at high angles of attack. This information is giving engineers and aircraft designers a better understanding of aerodynamics, effectiveness of flight controls and thrust vectoring, and airflow phenomena at high angles of attack. This understanding is expected to lead to design methods that provide better maneuverability in future high performance aircraft and make them safer to fly. An international test organization of about 110 people, managed by the Advanced Research Projects Agency (ARPA), conducted the flight operations at NASA Dryden. The ARPA had requested flight research for the X-31 aircraft be moved there in February 1992. In addition to ARPA and NASA, the international test organization (ITO) included the U.S. Navy, the U.S. Air Force, Rockwell International, the Federal Republic of Germany, and Daimler-Benz Aerospace (formerly Messerschmitt-Bolkow-Blohm and Deutsche Aerospace). NASA was responsible for flight research operations, aircraft maintenance, and research engineering once the program moved to Dryden. The No. 1 X-31 aircraft was lost in an accident January 19, 1995. The pilot, Karl Heinz-Lang, of the Federal Republic of Germany, ejected safely before the aircraft crashed in an unpopulated desert area just north of Edwards. The X-31 program logged an X-plane record of 580 flights during the program, including 555 research missions and 21 in Europe for the 1995 Paris Air Show. A total of 14 pilots representing all agencies of the ITO flew the aircraft. The X-31 aircraft shown on approach with a high angle of attack, touches down with its speed brakes, which can be seen extended just above and behind the wing. The aircraft then begins to rotate the nosegear down to runway contact and deploys a braking parachute that assists in slowing the aircraft after landing.
X-45A Air Vehicle #1 during flight #13, with weapons bay door open
2003-02-21
The DARPA/U.S. Air Force X-45A Unmanned Combat Air Vehicle (UCAV) system demonstration program completed the first phase of demonstrations, known as Block I, on Feb. 28, 2003. The final Block I activities included two flights at Dryden, during which safe operation of the weapons bay door was verified at 35,000 feet and speeds of Mach 0.75, the maximum planned altitude and speed for the two X-45A demonstrator vehicles.
The X-15/HL-20 operations support comparison
NASA Technical Reports Server (NTRS)
Morris, W. Douglas
1993-01-01
During the 1960's, the United States X-15 rocket-plane research program successfully demonstrated the ability to support a reusable vehicle operating in a near-space environment. The similarity of the proposed HL-20 lifting body concept in general size, weight, and subsystem composition to that of the X-15 provided an opportunity for a comparison of the predicted support manpower and turnaround times with those experienced in the X-15 program. Information was drawn from both reports and discussions with X-15 program personnel to develop comparative operations and support data. Based on the assumption of comparability between the two systems, the predicted staffing levels, skill mix, and refurbishment times of an operational HL-20 appear to be similar to those experienced by the X-15 for ground support. However, safety, environmental, and support requirements have changed such that the HL-20 will face a different operating environment than existed at Edwards during the 1950's and 1960's. Today's operational standards may impose additional requirements on the HL-20 that will add to the maintenance and support burden estimate based on the X-15 analogy.
DOE Office of Scientific and Technical Information (OSTI.GOV)
K. Payette; D. Tillman
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 cofiringmore » 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.« less
Method and apparatus to selectively reduce NO.sub.x in an exhaust gas feedstream
Schmieg, Steven J [Troy, MI; Blint, Richard J [Shelby Township, MI; Den, Ling [Sterling Heights, MI; Viola, Michael B [Macomb Township, MI; Lee, Jong-Hwan [Rochester Hills, MI
2011-08-30
A method and apparatus are described to selectively reduce NO.sub.x emissions of an internal combustion engine. An exhaust aftertreatment system includes an injection device operative to dispense a hydrocarbon reductant upstream of a silver-alumina catalytic reactor device. A control system determines a NO.sub.x concentration and hydrocarbon/NOx ratio based upon selected parameters of the exhaust gas feedstream and dispenses hydrocarbon reductant during lean engine operation. Included is a method to control elements of the feedstream during lean operation. The hydrocarbon reductant may include engine fuel.
Design of dual multiple aperture devices for dynamical fluence field modulated CT.
Mathews, Aswin John; Tilley, Steven; Gang, Grace; Kawamoto, Satomi; Zbijewski, Wojciech; Siewerdsen, Jeffrey H; Levinson, Reuven; Webster Stayman, J
2016-07-01
A Multiple Aperture Device (MAD) is a novel x-ray beam modulator that uses binary filtration on a fine scale to spatially modulate an x-ray beam. Using two MADs in series enables a large variety of fluence profiles by shifting the MADS relative to each other. This work details the design and control of dual MADs for a specific class of desired fluence patterns. Specifically, models of MAD operation are integrated into a best fit objective followed by CMA-ES optimization. To illustrate this framework we demonstrate the design process for an abdominal phantom with the goal of uniform detected signal. Achievable fluence profiles show good agreement with target fluence profiles, and the ability to flatten projections when a phantom is scanned is demonstrated. Simulated data reconstruction using traditional tube current modulation (TCM) and MAD filtering with TCM are investigated with the dual MAD system demonstrating more uniformity in noise and illustrating the potential for dose reduction under a maximum noise level constraint.
2016-09-23
Acquisition and Data Analysis). EMI sensors, MetalMapper, man-portable Time-domain Electromagnetic Multi-sensor Towed Array Detection System (TEMTADS...California Department of Toxic Substances Control EM61 EM61-MK2 EMI electromagnetic induction ESTCP Environmental Security Technology Certification...SOP Standard Operating Procedure v TEMTADS Time-domain Electromagnetic Multi-sensor Towed Array Detection System man-portable 2x2 TOI target(s
NASA Technical Reports Server (NTRS)
Gunapala, Sarath D.; Bandara, Sumith V.; Liu, John K.; Hill, Cory J.; Rafol, S. B.; Mumolo, Jason M.; Trinh, Joseph T.; Tidrow, M. Z.; Le Van, P. D.
2005-01-01
Mid-wavelength infrared (MWIR) and long-wavelength infrared (LWIR) 1024x1024 pixel quantum well infrared photodetector (QWIP) focal planes have been demonstrated with excellent imaging performance. The MWIR QWIP detector array has demonstrated a noise equivalent differential temperature (NE(Delta)T) of 17 mK at a 95K operating temperature with f/2.5 optics at 300K background and the LWIR detector array has demonstrated a NE(Delta)T of 13 mK at a 70K operating temperature with the same optical and background conditions as the MWIR detector array after the subtraction of system noise. Both MWIR and LWIR focal planes have shown background limited performance (BLIP) at 90K and 70K operating-temperatures respectively, with similar optical and background conditions. In addition, we are in the process of developing MWIR and LWIR pixel collocated simultaneously readable dualband QWIP focal plane arrays.
Miao, Wang; Luo, Jun; Di Lucente, Stefano; Dorren, Harm; Calabretta, Nicola
2014-02-10
We propose and demonstrate an optical flat datacenter network based on scalable optical switch system with optical flow control. Modular structure with distributed control results in port-count independent optical switch reconfiguration time. RF tone in-band labeling technique allowing parallel processing of the label bits ensures the low latency operation regardless of the switch port-count. Hardware flow control is conducted at optical level by re-using the label wavelength without occupying extra bandwidth, space, and network resources which further improves the performance of latency within a simple structure. Dynamic switching including multicasting operation is validated for a 4 x 4 system. Error free operation of 40 Gb/s data packets has been achieved with only 1 dB penalty. The system could handle an input load up to 0.5 providing a packet loss lower that 10(-5) and an average latency less that 500 ns when a buffer size of 16 packets is employed. Investigation on scalability also indicates that the proposed system could potentially scale up to large port count with limited power penalty.
X-24B on Lakebed Showing Upper Body Shape
NASA Technical Reports Server (NTRS)
1972-01-01
The sleek, futuristic shape of the X-24B lifting body research vehicle can be clearly seen in this look-down view of the aircraft on Rogers Dry Lake, adjacent to the NASA Flight Research Center, Edwards, California. The X-24 was one of a group of lifting bodies flown by the NASA Flight Research Center (now Dryden Flight Research Center), Edwards, California, in a joint program with the U.S. Air Force at Edwards Air Force Base from 1963 to 1975. The lifting bodies were used to demonstrate the ability of pilots to maneuver and safely land wingless vehicles designed to fly back to Earth from space and be landed like an airplane at a predetermined site. Lifting bodies' aerodynamic lift, essential to flight in the atmosphere, was obtained from their shape. The addition of fins and control surfaces allowed the pilots to stabilize and control the vehicles and regulate their flight paths. Built by Martin Aircraft Company, Maryland, for the U.S. Air Force, the X-24A was a bulbous vehicle shaped like a teardrop with three vertical fins at the rear for directional control. It weighed 6,270 pounds, was 24.5 feet long and 11.5 feet wide (measuring just the fuselage, not the distance between the tips of the outboard fins). Its first unpowered glide flight was on April 17, 1969, with Air Force Maj. Jerauld Gentry at the controls. Gentry also piloted its first powered flight on March 19, 1970. The X-24A was flown 28 times in the program that, like the HL-10, validated the concept that a Space Shuttle vehicle could be landed unpowered. The fastest speed achieved by the X-24A was 1,036 miles per hour (mph-Mach 1.6). Its maximum altitude was 71,400 feet. It was powered by an XLR-11 rocket engine with a maximum theoretical vacuum thrust of 8,480 pounds. The X-24A was later modified into the X-24B. The bulbous shape of the X-24A was converted into a 'flying flatiron' shape with a rounded top, flat bottom, and double delta platform that ended in a pointed nose. The X-24B demonstrated that accurate unpowered reentry vehicle landings were operationally feasible. Top speed achieved by the X-24B was 1,164 mph and the highest altitude it reached was 74,130 feet. The vehicle is on display at the Air Force Museum, Wright-Patterson Air Force Base, Ohio. The pilot on the last powered flight of the X-24B was Bill Dana, who also flew the last X-15 flight about seven years earlier. The X-24A shape was later borrowed for the X-38 Crew Return Vehicle (CRV) technology demonstrator for the International Space Station. The X-24B is on public display at the Air Force Museum, Wright-Patterson AFB, Ohio.
A Control System and Streaming DAQ Platform with Image-Based Trigger for X-ray Imaging
NASA Astrophysics Data System (ADS)
Stevanovic, Uros; Caselle, Michele; Cecilia, Angelica; Chilingaryan, Suren; Farago, Tomas; Gasilov, Sergey; Herth, Armin; Kopmann, Andreas; Vogelgesang, Matthias; Balzer, Matthias; Baumbach, Tilo; Weber, Marc
2015-06-01
High-speed X-ray imaging applications play a crucial role for non-destructive investigations of the dynamics in material science and biology. On-line data analysis is necessary for quality assurance and data-driven feedback, leading to a more efficient use of a beam time and increased data quality. In this article we present a smart camera platform with embedded Field Programmable Gate Array (FPGA) processing that is able to stream and process data continuously in real-time. The setup consists of a Complementary Metal-Oxide-Semiconductor (CMOS) sensor, an FPGA readout card, and a readout computer. It is seamlessly integrated in a new custom experiment control system called Concert that provides a more efficient way of operating a beamline by integrating device control, experiment process control, and data analysis. The potential of the embedded processing is demonstrated by implementing an image-based trigger. It records the temporal evolution of physical events with increased speed while maintaining the full field of view. The complete data acquisition system, with Concert and the smart camera platform was successfully integrated and used for fast X-ray imaging experiments at KIT's synchrotron radiation facility ANKA.
NASA Technical Reports Server (NTRS)
Engelund, Walter C.; Holland, Scott D.; Cockrell, Charles E., Jr.; Bittner, Robert D.
1999-01-01
NASA's Hyper-X Research Vehicle will provide a unique opportunity to obtain data on an operational airframe integrated scramjet propulsion system at true flight conditions. The airframe integrated nature of the scramjet engine with the Hyper-X vehicle results in a strong coupling effect between the propulsion system operation and the airframe s basic aerodynamic characteristics. Comments on general airframe integrated scramjet propulsion system effects on vehicle aerodynamic performance, stability, and control are provided, followed by examples specific to the Hyper-X research vehicle. An overview is provided of the current activities associated with the development of the Hyper-X aerodynamic database, including wind tunnel test activities and parallel CFD analysis efforts. A brief summary of the Hyper-X aerodynamic characteristics is provided, including the direct and indirect effects of the airframe integrated scramjet propulsion system operation on the basic airframe stability and control characteristics.
Propellant Feed Subsystem for the X-34 Main Propulsion System
NASA Technical Reports Server (NTRS)
McDonald, J. P.; Minor, R. B.; Knight, K. C.; Champion, R. H., Jr.; Russell, F. J., Jr.
1998-01-01
The Orbital Sciences Corporation X-34 vehicle demonstrates technologies and operations key to future reusable launch vehicles. The general flight performance goal of this unmanned rocket plane is Mach 8 flight at an altitude of 250,000 feet. The Main Propulsion System supplies liquid propellants to the main engine, which provides the primary thrust for attaining mission goals. Major NMS design and operational goals are aircraft-like ground operations, quick turnaround between missions, and low initial/operational costs. This paper reviews major design and analysis aspects of the X-34 propellant feed subsystem of the X-34 Main Propulsion System. Topics include system requirements, system design, the integration of flight and feed system performance, propellant acquisition at engine start, and propellant tank terminal drain.
Wu, Kai-cheng; Wu, Peng; Shen, Yao-liang; Li, Yue-han; Wang, Han-fang; Xu, Yue-zhong
2015-11-01
Abstract: The last two compartments of the Anaerobic Baffled Readtor ( ABR) were altered into aeration tank and sedimentation tank respectively to get an integrated anaerobic-aerobic reactor, using anaerobic granular sludge in anaerobic zone and aerobic granular sludge in aerobic zone as seed sludge. The research explored the condition to cultivate nitritation granular sludge, under the condition of continuous flow. The C/N rate was decreased from 1 to 0.4 and the ammonia nitrogen volumetric loading rate was increased from 0.89 kg x ( m3 x d)(-1) to 2.23 kg x (m3 x d)(-1) while the setting time of 1 h was controlled in the aerobic zone. After the system was operated for 45 days, the mature nitritation granular sludge in aerobic zone showed a compact structure and yellow color while the nitrite accumulation rate was about 80% in the effluent. The associated inhibition of free ammonia (FA) and free nitrous acid (FNA) dominated the nitritation. Part of granules lost stability during the initial period of operation and flocs appeared in the aerobic zone. However, the flocs were transformed into newly generated small particles in the following reactor operation, demonstrating that organic carbon was benefit to granulation and the enrichment of slow-growing nitrifying played an important role in the stability of granules.
X-24A in Powered Flight after Drop from B-52 Mothership
NASA Technical Reports Server (NTRS)
1970-01-01
The X-24A lights its XLR-11 rocket engine and begins its powered flight after being drop launched from its B-52 mothership, seen here with high-altitude contrails streaming from its wings against a piercingly dark blue sky. The X-24 was one of a group of lifting bodies flown by the NASA Flight Research Center (now Dryden Flight Research Center), Edwards, California, in a joint program with the U.S. Air Force at Edwards Air Force Base from 1963 to 1975. The lifting bodies were used to demonstrate the ability of pilots to maneuver and safely land wingless vehicles designed to fly back to Earth from space and be landed like an airplane at a predetermined site. Lifting bodies' aerodynamic lift, essential to flight in the atmosphere, was obtained from their shape. The addition of fins and control surfaces allowed the pilots to stabilize and control the vehicles and regulate their flight paths. Built by Martin Aircraft Company, Maryland, for the U.S. Air Force, the X-24A was a bulbous vehicle shaped like a teardrop with three vertical fins at the rear for directional control. It weighed 6,270 pounds, was 24.5 feet long and 11.5 feet wide (measuring just the fuselage, not the distance between the tips of the outboard fins). Its first unpowered glide flight was on April 17, 1969, with Air Force Maj. Jerauld Gentry at the controls. Gentry also piloted its first powered flight on March 19, 1970. The X-24A was flown 28 times in the program that, like the HL-10, validated the concept that a Space Shuttle vehicle could be landed unpowered. The fastest speed achieved by the X-24A was 1,036 miles per hour (mph-Mach 1.6). Its maximum altitude was 71,400 feet. It was powered by an XLR-11 rocket engine with a maximum theoretical vacuum thrust of 8,480 pounds. The X-24A was later modified into the X-24B. The bulbous shape of the X-24A was converted into a 'flying flatiron' shape with a rounded top, flat bottom, and double delta platform that ended in a pointed nose. The X-24B demonstrated that accurate unpowered reentry vehicle landings were operationally feasible. Top speed achieved by the X-24B was 1,164 mph and the highest altitude it reached was 74,130 feet. The vehicle is on display at the Air Force Museum, Wright-Patterson Air Force Base, Ohio. The pilot on the last powered flight of the X-24B was Bill Dana, who also flew the last X-15 flight about seven years earlier. The X-24A shape was later borrowed for the X-38 Crew Return Vehicle (CRV) technology demonstrator for the International Space Station.
Demonstration of catalytic combustion with residual fuel
NASA Technical Reports Server (NTRS)
Dodds, W. J.; Ekstedt, E. E.
1981-01-01
An experimental program was conducted to demonstrate catalytic combustion of a residual fuel oil. Three catalytic reactors, including a baseline configuration and two backup configurations based on baseline test results, were operated on No. 6 fuel oil. All reactors were multielement configurations consisting of ceramic honeycomb catalyzed with palladium on stabilized alumina. Stable operation on residual oil was demonstrated with the baseline configuration at a reactor inlet temperature of about 825 K (1025 F). At low inlet temperature, operation was precluded by apparent plugging of the catalytic reactor with residual oil. Reduced plugging tendency was demonstrated in the backup reactors by increasing the size of the catalyst channels at the reactor inlet, but plugging still occurred at inlet temperature below 725 K (845 F). Operation at the original design inlet temperature of 589 K (600 F) could not be demonstrated. Combustion efficiency above 99.5% was obtained with less than 5% reactor pressure drop. Thermally formed NO sub x levels were very low (less than 0.5 g NO2/kg fuel) but nearly 100% conversion of fuel-bound nitrogen to NO sub x was observed.
NASA Technical Reports Server (NTRS)
1995-01-01
Two X-31 Enhanced Fighter Maneuverability (EFM) demonstrators were flown at the Rockwell International facility, Palmdale, California, and the NASA Dryden Flight Research Center, Edwards, California, to obtain data that may apply to the design of highly-maneuverable next-generation fighters. The program had its first flight on October 11, 1990, in Palmdale; it ended in June 1995. The X-31 program demonstrated the value of thrust vectoring (directing engine exhaust flow) coupled with advanced flight control systems, to provide controlled flight during close-in air combat at very high angles of attack. The result of this increased maneuverability is an airplane with a significant advantage over conventional fighters. 'Angle-of-attack' (alpha) is an engineering term to describe the angle of an aircraft body and wings relative to its actual flight path. During maneuvers, pilots often fly at extreme angles of attack -- with the nose pitched up while the aircraft continues in its original direction. This can lead to loss of control and result in the loss of the aircraft, pilot or both. Three thrust-vectoring paddles made of graphite epoxy mounted on the exhaust nozzle of the X-31 aircraft directed the exhaust flow to provide control in pitch (up and down) and yaw (right and left) to improve control. The paddles can sustain heat of up to 1,500 degrees centigrade for extended periods of time. In addition the X-31 aircraft were configured with movable forward canards and fixed aft strakes. The canards were small wing-like structures set on the wing line between the nose and the leading edge of the wing. The strakes were set on the same line between the trailing edge of the wing and the engine exhaust. Both supplied additional control in tight maneuvering situations. The X-31 research program produced technical data at high angles of attack. This information is giving engineers and aircraft designers a better understanding of aerodynamics, effectiveness of flight controls and thrust vectoring, and airflow phenomena at high angles of attack. This understanding is expected to lead to design methods that provide better maneuverability in future high performance aircraft and make them safer to fly. An international test organization of about 110 people, managed by the Advanced Research Projects Agency (ARPA), conducted the flight operations at NASA Dryden. The ARPA had requested flight research for the X-31 aircraft be moved there in February 1992. In addition to ARPA and NASA, the international test organization (ITO) included the U.S. Navy, the U.S. Air Force, Rockwell International, the Federal Republic of Germany, and Daimler-Benz Aerospace (formerly Messerschmitt-Bolkow-Blohm and Deutsche Aerospace). NASA was responsible for flight research operations, aircraft maintenance, and research engineering once the program moved to Dryden. The No. 1 X-31 aircraft was lost in an accident January 19, 1995. The pilot, Karl Heinz-Lang, of the Federal Republic of Germany, ejected safely before the aircraft crashed in an unpopulated desert area just north of Edwards. The X-31 program logged an X-plane record of 580 flights during the program, including 555 research missions and 21 in Europe for the 1995 Paris Air Show. A total of 14 pilots representing all agencies of the ITO flew the aircraft. This 32-second clip shows the aircraft at the top of a stall and then thrust vectoring itself around to attain a new heading, thereby allowing the aircraft to gain the advantage over a putative opponent in air-to-air combat. This maneuver is also known as a 'J turn.'
Radley, Ian [Glenmont, NY; Bievenue, Thomas J [Delmar, NY; Burdett, John H [Charlton, NY; Gallagher, Brian W [Guilderland, NY; Shakshober, Stuart M [Hudson, NY; Chen, Zewu [Schenectady, NY; Moore, Michael D [Alplaus, NY
2008-06-08
An x-ray source assembly and method of operation are provided having enhanced output stability. The assembly includes an anode having a source spot upon which electrons impinge and a control system for controlling position of the anode source spot relative to an output structure. The control system can maintain the anode source spot location relative to the output structure notwithstanding a change in one or more operating conditions of the x-ray source assembly. One aspect of the disclosed invention is most amenable to the analysis of sulfur in petroleum-based fuels.
2002-12-19
The first X-45A Unmanned Combat Air Vehicle (UCAV) technology demonstrator completed its sixth flight on Dec. 19, 2002, raising its landing gear in flight for the first time. The X-45A flew for 40 minutes and reached an airspeed of 195 knots and an altitude of 7,500 feet. Dryden is supporting the DARPA/Boeing team in the design, development, integration, and demonstration of the critical technologies, processes, and system attributes leading to an operational UCAV system. Dryden support of the X-45A demonstrator system includes analysis, component development, simulations, ground and flight tests.
Ares I-X Flight Test - The Future Begins Here
NASA Technical Reports Server (NTRS)
Davis, Stephan R.
2008-01-01
In less than two years, the National Aeronautics and Space Administration (NASA) will launch the Ares I-X mission. This will be the first flight of the Ares I crew launch vehicle, which, together with the Ares V cargo launch vehicle, will eventually send humans to the Moon, Mars, and beyond. As the countdown to this first Ares mission continues, personnel from across the Ares I-X Mission Management Office (MMO) are finalizing designs and fabricating vehicle hardware for an April 2009 launch. This paper will discuss the hardware and programmatic progress of the Ares I-X mission. Like the Apollo program, the Ares launch vehicles will rely upon extensive ground, flight, and orbital testing before sending the Orion crew exploration vehicle into space with humans on board. The first flight of Ares I, designated Ares I-X, will be a suborbital development flight test. Ares I-X gives NASA its first opportunity to gather critical data about the flight dynamics of the integrated launch vehicle stack; understand how to control its roll during flight; better characterize the severe stage separation environments that the upper stage engine will experience during future operational flights; and demonstrate the first stage recovery system. NASA also will begin modifying the launch infrastructure and fine-tuning ground and mission operations, as the agency makes the transition from the Space Shuttle to the Ares/Orion system.
The success of the X-33 depends on its technology—an overview
NASA Astrophysics Data System (ADS)
Bunting, Jackie O.; Sasso, Steven E.
1996-03-01
The success of the X-33, and therefore the Reusable Launch Vehicle (RLV) program, is highly dependent on the maturity of the components and subsystems selected and the ability to verify their performance, cost, and operability goals. The success of the technology that will be developed to support these components and subsystems will be critical to developing an operationally efficient X-33 that is traceable to a full-scale RLV system. This paper will delineate the key objectives of each technology demonstration area and provide an assessment of its ability to meet the X-33/RLV requirements. It is our intent to focus on these key technology areas to achieve the ambitious but achievable goals of the RLV and X-33 programs. Based on our assessment of the X-33 and RLV systems, we have focused on the performance verification and validation of the linear aerospike engine. This engine, first developed in the mid-1960s, shows promise in achieving the RLV objectives. Equally critical to the engine selection is the development of cryogenic composite tanks and the associated health management system required to meet the operability goals. We are also developing a highly reusable form of thermal protection system based on years of hypersonic research and Space Shuttle experience. To meet the mass fraction goals, reduction in engine component weights will also be developed. Due to the high degree of operability required, we will investigate the use of real-time integrated system health management and propulsion systems diagnostics, and mature the use of electromechanical actuators for highly reusable systems. The rapid turn-around requirements will require an adaptive guidance, navigation, and control algorithm toolset, which is well underway. We envision our X-33 and RLV to use mature, low-risk technologies that will allow truly low-cost access to space (Lockheed Martin Internal Document, 1995).
Propulsion Technology Demonstrator. [Demonstrating Novel CubeSat Technologies in Low Earth Orbit
NASA Technical Reports Server (NTRS)
Marmie, John; Martinez, Andres; Petro, Andrew
2015-01-01
NASA's Pathfinder Technology Demonstrator (PTD) project will test the operation of a variety of novel CubeSat technologies in low- Earth orbit, providing significant enhancements to the performance of these small and effective spacecraft. Each Pathfinder Technology Demonstrator mission consists of a 6-unit (6U) CubeSat weighing approximately 26 pounds (12 kilograms) and measuring 12 inches x 10 inches x 4 inches (30 centimeters x 25 centimeters x 10 centimeters), comparable in size to a common shoebox. CubeSats are a class of nanosatellites that use a standard size and form factor. The standard Cube- Sat size uses a "one unit" or "1U" measuring 4 inches x 4 inches x 4 inches (10x10x10 centimeters) and is extendable to larger sizes by "stacking" a number of the 1U blocks to form a larger spacecraft. Each PTD spacecraft will also be equipped with deployable solar arrays that provide an average of 44 watts of power while in orbit.
X-38 V201 Avionics Architecture
NASA Technical Reports Server (NTRS)
Bedos, Thierry; Anderson, Brian L.
1999-01-01
The X-38 is an experimental NASA project developing a core human capable spacecraft at a fraction of the cost of any previous human rated vehicle. The first operational derivative developed from the X-38 program will be the International Space Station (ISS) Crew Return Vehicle (CRV). Although the current X-38 vehicles are designed as re-entry vehicles only, the option exists to modify the vehicle for uses as an upward vehicle launched from an expendable launch vehicle or from the X-33 operational derivative. The Operational CRV, that will be derived from the X-38 spaceflight vehicle, will provide an emergency return capability from the International Space Station (ISS). The spacecraft can hold a crew of up to seven inside a pressurized cabin. The CRV is passively delivered to ISS, stays up to three year on-orbit attached to ISS in a passive mode with periodic functional checkout, before separation from ISS, de-orbit, entry and landing. The X-38 Vehicle 201 (V201) is being developed at NASA/JSC to demonstrate key technologies associated with the development of the CRV design. The X-38 flight test will validate the low cost development concept by demonstrating the entire station departure, re-entry, guidance and landing portions of the CRV mission. All new technologies and subsystems proposed for CRV will be validated during either the on orbit checkout or flight phases of the X-38 space flight test. The X-38 subsystems are required to be similar to those subsystems required for the CRV to the greatest extent possible. In many cases, the subsystems are identical to those that will be utilized on the Operational CRV.
X-31 in flight - Post Stall Maneuver
NASA Technical Reports Server (NTRS)
1995-01-01
Two X-31 Enhanced Fighter Maneuverability (EFM) demonstrators were flown at Rockwell International's Palmdale, Calif., facility and the NASA Dryden Flight Research Center, Edwards, Calif., to obtain data that may apply to the design of highly-maneuverable next-generation fighters. The program had its first flight on Oct. 11, 1990, in Palmdale; it ended in June 1995. The X-31 program demonstrated the value of thrust vectoring (directing engine exhaust flow) coupled with advanced flight control systems, to provide controlled flight during close-in air combat at very high angles of attack. The result of this increased maneuverability is a significant advantage over conventional fighters. 'Angle-of-attack' (alpha) is an engineering term to describe the angle of an aircraft's body and wings relative to its actual flight path. During maneuvers, pilots often fly at extreme angles of attack -- with the nose pitched up while the aircraft continues in its original direction. This can lead to loss of control and result in the loss of the aircraft, pilot or both. Three thrust vectoring paddles made of graphite epoxy mounted on the X-31's exhaust nozzle directed the exhaust flow to provide control in pitch (up and down) and yaw (right and left) to improve control. The paddles can sustain heat of up to 1,500 degrees centigrade for extended periods of time. In addition the X-31s were configured with movable forward canards and fixed aft strakes. The canards were small wing-like structures set on the wing line between the nose and the leading edge of the wing. The strakes were set on the same line between the trailing edge of the wing and the engine exhaust. Both supplyied additional control in tight maneuvering situations. The X-31 research program produced technical data at high angles of attack. This information is giving engineers and aircraft designers a better understanding of aerodynamics, effectiveness of flight controls and thrust vectoring, and airflow phenomena at high angles of attack. This is expected to lead to design methods providing better maneuverability in future high performance aircraft and make them safer to fly. An international test organization of about 110 people, managed by the Advanced Research Projects Agency (ARPA), conducted the flight operations at Dryden, to which flight research was moved in February 1992 at the request of the Advanced Research Projects Agency (ARPA). In addition to ARPA and NASA, the International Test Organization (ITO) included the U.S. Navy, the U.S. Air Force, Rockwell International, the Federal Republic of Germany, and Daimler-Benz Aerospace (formerly Messerschmitt-Bolkow-Blohm and Deutsche Aerospace). NASA was responsible for flight research operations, aircraft maintenance, and research engineering once the program moved to Dryden. The No. 1 X-31 aircraft was lost in an accident Jan. 19, 1995. The pilot, Karl Heinz-Lang, of the Federal Republic of Germany, ejected safely before the aircraft crashed in an unpopulated desert area just north of Edwards. The X-31 program logged an X-plane record of 580 flights during the program, including 555 research missions and 21 in Europe for the 1995 Paris Air Show. A total of 14 pilots representing all agencies of the ITO flew the aircraft. This 34-second movie clip shows the aircraft as it slides backwards, thrust vectoring the tail over the top, turning the stall into a loop in which the aircraft then reverses it's heading and resumes level flight.
X-33 Injector Ignition Single Cell Test
NASA Technical Reports Server (NTRS)
1997-01-01
The X-33 injector ignition single cell was tested at the Marshall Space Flight Center test stand 116. The X-33 was a sub-scale technology demonstrator prototype of a Reusable Launch Vehicle (RLV) manufactured and named by Lockheed Martin as the Venture Star. The goal of the program was to demonstrate the technologies needed for a full size, single-stage-to-orbit RLV, thus enabling private industry to build and operate the RLV in the first decade of the 21st century. The X-33 program was cancelled in 2001.
Radley, Ian; Bievenue, Thomas J.; Burdett Jr., John H.; Gallagher, Brian W.; Shakshober, Stuart M.; Chen, Zewu; Moore, Michael D.
2007-04-24
An x-ray source assembly (2700) and method of operation are provided having enhanced output stability. The assembly includes an anode (2125) having a source spot upon which electrons (2120) impinge and a control system (2715/2720) for controlling position of the anode source spot relative to an output structure. The control system can maintain the anode source spot location relative to the output structure (2710) notwithstanding a change in one or more operating conditions of the x-ray source assembly. One aspect of the disclosed invention is most amenable to the analysis of sulfur in petroleum-based fuels.
Operator Influence of Unexploded Ordnance Sensor Technologies
2007-03-01
chart display ActiveX control Mscomct2.dll – date/time display ActiveX control Pnpscr.dll – Systran SCRAMNet replicated shared memory device...response value database rgm_p2.dll – Phase 2 shared memory API and implementation Commercial components StripM.ocx – strip chart display ActiveX
Compact, closed-loop controlled waste incinerator
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schadow, K.C.; Seeker, W.R.
1999-07-01
Technologies for solid and liquid waste destruction in compact incinerators are being developed in collaboration between industry, universities, and a Government laboratory. This paper reviews progress on one technology, namely active combustion control to achieve efficient and controlled afterburning of air-starved reaction products. This technology which uses synchronized waste gas injection into acoustically stabilized air vortices was transitioned to a simplified afterburner design and practical operational conditions. The full-scale, simplified afterburner, which achieved CO and NO{sub x} emissions of about 30 ppm with a residence time of less than 50 msec, was integrated with a commercially available marine incinerator tomore » increase throughput and reduce emissions. Closed-loop active control with diode laser sensors and novel control strategies was demonstrated on a sub-scale afterburner.« less
X-43D Conceptual Design and Feasibility Study
NASA Technical Reports Server (NTRS)
Johnson, Donald B.; Robinson, Jeffrey S.
2005-01-01
NASA s Next Generation Launch Technology (NGLT) Program, in conjunction with the office of the Director of Defense Research and Engineering (DDR&E), developed an integrated hypersonic technology demonstration roadmap. This roadmap is an integral part of the National Aerospace Initiative (NAI), a multi-year, multi-agency cooperative effort to invest in and develop, among other things, hypersonic technologies. This roadmap contains key ground and flight demonstrations required along the path to developing a reusable hypersonic space access system. One of the key flight demonstrations required for systems that will operate in the high Mach number regime is the X-43D. As currently conceived, the X-43D is a Mach 15 flight test vehicle that incorporates a hydrogen-fueled scramjet engine. The purpose of the X-43D is to gather high Mach number flight environment and engine operability information which is difficult, if not impossible, to gather on the ground. During 2003, the NGLT Future Hypersonic Flight Demonstration Office initiated a feasibility study on the X-43D. The objective of the study was to develop a baseline conceptual design, assess its performance, and identify the key technical issues. The study also produced a baseline program plan, schedule, and cost, along with a list of key programmatic risks.
DAC-board based X-band EPR spectrometer with arbitrary waveform control
NASA Astrophysics Data System (ADS)
Kaufmann, Thomas; Keller, Timothy J.; Franck, John M.; Barnes, Ryan P.; Glaser, Steffen J.; Martinis, John M.; Han, Songi
2013-10-01
We present arbitrary control over a homogenous spin system, demonstrated on a simple, home-built, electron paramagnetic resonance (EPR) spectrometer operating at 8-10 GHz (X-band) and controlled by a 1 GHz arbitrary waveform generator (AWG) with 42 dB (i.e. 14-bit) of dynamic range. Such a spectrometer can be relatively easily built from a single DAC (digital to analog converter) board with a modest number of stock components and offers powerful capabilities for automated digital calibration and correction routines that allow it to generate shaped X-band pulses with precise amplitude and phase control. It can precisely tailor the excitation profiles "seen" by the spins in the microwave resonator, based on feedback calibration with experimental input. We demonstrate the capability to generate a variety of pulse shapes, including rectangular, triangular, Gaussian, sinc, and adiabatic rapid passage waveforms. We then show how one can precisely compensate for the distortion and broadening caused by transmission into the microwave cavity in order to optimize corrected waveforms that are distinctly different from the initial, uncorrected waveforms. Specifically, we exploit a narrow EPR signal whose width is finer than the features of any distortions in order to map out the response to a short pulse, which, in turn, yields the precise transfer function of the spectrometer system. This transfer function is found to be consistent for all pulse shapes in the linear response regime. In addition to allowing precise waveform shaping capabilities, the spectrometer presented here offers complete digital control and calibration of the spectrometer that allows one to phase cycle the pulse phase with 0.007° resolution and to specify the inter-pulse delays and pulse durations to ⩽250 ps resolution. The implications and potential applications of these capabilities will be discussed.
NASA Astrophysics Data System (ADS)
Black, Stephen T.; Eshleman, Wally
1997-01-01
This paper describes the VentureStar™ SSTO RLV and X-33 operations concepts. Applications of advanced technologies, automated ground support systems, advanced aircraft and launch vehicle lessons learned have been integrated to develop a streamlined vehicle and mission processing concept necessary to meet the goals of a commercial SSTO RLV. These concepts will be validated by the X-33 flight test program where financial and technical risk mitigation are required. The X-33 flight test program totally demonstrates the vehicle performance, technology, and efficient ground operations at the lowest possible cost. The Skunk Work's test program approach and test site proximity to the production plant are keys. The X-33 integrated flight and ground test program incrementally expands the knowledge base of the overall system allowing minimum risk progression to the next flight test program milestone. Subsequent X-33 turnaround processing flows will be performed with an aircraft operations philosophy. The differences will be based on research and development, component reliability and flight test requirements.
Multicolor megapixel QWIP focal plane arrays for remote sensing instruments
NASA Astrophysics Data System (ADS)
Gunapala, S. D.; Bandara, S. V.; Liu, J. K.; Hill, C. J.; Rafol, S. B.; Mumolo, J. M.; Trinh, J. T.; Tidrow, M. Z.; LeVan, P. D.
2006-08-01
Mid-wavelength infrared (MWIR) and long-wavelength infrared (LWIR) 1024x1024 pixel quantum well infrared photodetector (QWIP) focal planes have been demonstrated with excellent imaging performance. The MWIR QWIP detector array has demonstrated a noise equivalent differential temperature (NEΔT) of 17 mK at a 95K operating temperature with f/2.5 optics at 300K background and the LWIR detector array has demonstrated a NEΔT of 13 mK at a 70K operating temperature with the same optical and background conditions as the MWIR detector array after the subtraction of system noise. Both MWIR and LWIR focal planes have shown background limited performance (BLIP) at 90K and 70K operating temperatures respectively, with similar optical and background conditions. In addition, we have demonstrated MWIR and LWIR pixel co-registered simultaneously readable dualband QWIP focal plane arrays. In this paper, we will discuss the performance in terms of quantum efficiency, NEΔT, uniformity, operability, and modulation transfer functions of the 1024x1024 pixel arrays and the progress of dualband QWIP focal plane array development work.
Andalib, Mehran; Taher, Edris; Donohue, Joseph; Ledwell, Sam; Andersen, Mikkel H; Sangrey, Karla
2018-01-01
The reliability and accuracy of in-situ ion selective electrode and ultraviolet (NO x ) probes have been investigated at four different treatment plants with different operational conditions. This study shows that the mentioned probes tend to compromise their accuracy and trending stability at lower NO x of <1.0 mg N/L, which if used as a measuring variable for PI feedback controller for denitrification (biological reduction of nitrate to nitrogen gas), would cause overfeeding the external carbon source. In-situ Clark-type N 2 O sensors, recently introduced for industrial scale use (Unisense Environment) could potentially open a new horizon in the automation of biological processes and particularly denitrification. To demonstrate the applicability of such probes for automation, two in-situ N 2 O probes were used in two treatment plants in parallel with NO x -N probes. The effects of operational conditions such as COD/N ratios and the correlation between NO x and N 2 O were investigated at those plants. N 2 O production at non-detect dissolved oxygen concentrations and pH of 7-7.2 were found to be a function of influent nitrogen load or the ratio of COD/N INFLUENT . Finally, using an N 2 O probe as a proxy sensor for nitrates is proposed as a measured variable in the PI feedback in the automation of the denitrification process with a NO x set point of <1.2 mg N/L).
NASA X-34 Technology in Motion
NASA Technical Reports Server (NTRS)
Beech, Geoffrey; Chandler, Kristie
1997-01-01
The X-34 technology development program is a joint industry/government project to develop, test, and operate a small, fully-reusable hypersonic flight vehicle. The objective is to demonstrate key technologies and operating concepts applicable to future reusable launch vehicles. Integrated in the vehicle are various systems to assure successful completion of mission objectives, including the Main Propulsion System (MPS). NASA-Marshall Space Flight Center (MSFC) is responsible for developing the X-34's MPS including the design and complete build package for the propulsion system components. The X-34 will be powered by the Fastrac Engine, which is currently in design and development at NASA-MSFC. Fastrac is a single-stage main engine, which burns a mixture of liquid oxygen (LOX) and kerosene(RP-1). The interface between the MPS and Fastrac engine are critical for proper system operation and technologies applicable to future reusable launch vehicles. Deneb's IGRIP software package with the Dynamic analysis option provided a key tool for conducting studies critical to this interface as well as a mechanism to drive the design of the LOX and RP-1 feedlines. Kinematic models were created for the Fastrac Engine and the feedlines for various design concepts. Based on the kinematic simulation within Envision, design and joint limits were verified and system interference controlled. It was also critical to the program to evaluate the effect of dynamic loads visually, providing a verification tool for dynamic analysis and in some cases uncovering areas that had not been considered. Deneb's software put the X-34 technology in motion and has been a key factor in facilitating the strenuous design schedule.
ESF-X: a low-cost modular experiment computer for space flight experiments
NASA Astrophysics Data System (ADS)
Sell, Steven; Zapetis, Joseph; Littlefield, Jim; Vining, Joanne
2004-08-01
The high cost associated with spaceflight research often compels experimenters to scale back their research goals significantly purely for budgetary reasons; among experiment systems, control and data collection electronics are a major contributor to total project cost. ESF-X was developed as an architecture demonstration in response to this need: it is a highly capable, radiation-protected experiment support computer, designed to be configurable on demand to each investigator's particular experiment needs, and operational in LEO for missions lasting up to several years (e.g., ISS EXPRESS) without scheduled service or maintenance. ESF-X can accommodate up to 255 data channels (I/O, A/D, D/A, etc.), allocated per customer request, with data rates up to 40kHz. Additionally, ESF-X can be programmed using the graphical block-diagram based programming languages Simulink and MATLAB. This represents a major cost saving opportunity for future investigators, who can now obtain a customized, space-qualified experiment controller at steeply reduced cost compared to 'new' design, and without the performance compromises associated with using preexisting 'generic' systems. This paper documents the functional benchtop prototype, which utilizes a combination of COTS and space-qualified components, along with unit-gravity-specific provisions appropriate to laboratory environment evaluation of the ESF-X design concept and its physical implementation.
2000-12-08
The X-40 sub-scale technology demonstrator is suspended under a U.S. Army CH-47 Chinook cargo helicopter during a captive-carry test flight at NASA's Dryden Flight Research Center, Edwards, California. The captive carry flights are designed to verify the X-40's navigation and control systems, rigging angles for its sling, and stability and control of the helicopter while carrying the X-40 on a tether. Following a series of captive-carry flights, the X-40 made free flights from a launch altitude of about 15,000 feet above ground, gliding to a fully autonomous landing. The X-40 is an unpowered 82 percent scale version of the X-37, a Boeing-developed spaceplane designed to demonstrate various advanced technologies for development of future lower-cost access to space vehicles.
Controlling soot formation with filtered EGR for diesel and biodiesel fuelled engines.
Gill, S S; Turner, D; Tsolakis, A; York, A P E
2012-04-03
Although exhaust gas recirculation (EGR) is an effective strategy for controlling the levels of nitrogen oxides (NO(X)) emitted from a diesel engine, the full potential of EGR in NO(X)/PM trade-off and engine performance (i.e., fuel economy) has not fully been exploited. Significant work into the cause and control of particulate matter (PM) has been made over the past decade with new cleaner fuels and after-treatment devices emerging to comply with the current and forthcoming emission regulations. In earlier work, we demonstrated that engine operation with oxygenated fuels (e.g., biodiesel) reduces the PM emissions and extends the engine tolerance to EGR before it reaches smoke-limited conditions. The same result has also been reported when high cetane number fuels such as gas-to-liquid (GTL) are used. To further our understanding of the relationship between EGR and PM formation, a diesel particulate filter (DPF) was integrated into the EGR loop to filter the recirculated soot particulates. The control of the soot recirculation penalty through filtered EGR (FEGR) resulted in a 50% engine-out soot reduction, thus showing the possibility of extending the maximum EGR limit or being able to run at the same level of EGR with an improved NO(X)/soot trade-off.
NASA Technical Reports Server (NTRS)
Kamhawi, Hani; Dankanich, John; Martinez, Andres; Petro, Andrew
2015-01-01
The Iodine Satellite (iSat) spacecraft will be the first CubeSat to demonstrate high change in velocity from a primary propulsion system by using Hall thruster technology and iodine as a propellant. The mission will demonstrate CubeSat maneuverability, including plane change, altitude change and change in its closest approach to Earth to ensure atmospheric reentry in less than 90 days. The mission is planned for launch in fall 2017. Hall thruster technology is a type of electric propulsion. Electric propulsion uses electricity, typically from solar panels, to accelerate the propellant. Electric propulsion can accelerate propellant to 10 times higher velocities than traditional chemical propulsion systems, which significantly increases fuel efficiency. To enable the success of the propulsion subsystem, iSat will also demonstrate power management and thermal control capabilities well beyond the current state-of-the-art for spacecraft of its size. This technology is a viable primary propulsion system that can be used on small satellites ranging from about 22 pounds (10 kilograms) to more than 1,000 pounds (450 kilograms). iSat's fuel efficiency is ten times greater and its propulsion per volume is 100 times greater than current cold-gas systems and three times better than the same system operating on xenon. iSat's iodine propulsion system consists of a 200 watt (W) Hall thruster, a cathode, a tank to store solid iodine, a power processing unit (PPU) and the feed system to supply the iodine. This propulsion system is based on a 200 W Hall thruster developed by Busek Co. Inc., which was previously flown using xenon as the propellant. Several improvements have been made to the original system to include a compact PPU, targeting greater than 80 percent reduction in mass and volume of conventional PPU designs. The cathode technology is planned to enable heaterless cathode conditioning, significantly increasing total system efficiency. The feed system has been designed to include iodine compatible control valves with internal heaters and temperature sensors to coincide with the iodine-compatible thruster. A key advantage to using iodine as a propellant is that it may be stored in the tank as an unpressurized solid on the ground and before flight operations. During operations, the tank is heated to vaporize the propellant. Iodine vapor is then routed through custom flow control valves to control mass flow to the thruster and cathode assembly. The thruster then ionizes the vapor and accelerates it via magnetic and electrostatic fields, resulting in high specific impulse, characteristic of a highly efficient propulsion system. The iSat spacecraft is a 12-unit (12U) CubeSat with dimensions of about 8 inches x 8 inches x 12 inches (20 centimeters x 20 centimeters x 30 centimeters). The spacecraft frame will be constructed from aluminum with a finish to prevent iodine-driven corrosion. The iSat spacecraft includes full three-axis control and will leverage heat generated by spacecraft components and radiators for a passive thermal control system. After the CubeSat has successfully detached from its launch vehicle, it will deploy its solar panels, correct for tip-off and maintain attitude control before ground contact. An initial check-out period of two weeks is planned for testing all subsystems. The spacecraft will charge the power system while in sunlight, using momentum wheels and magnetic torque rods to rotate the vehicle to the required attitude.
A cross-platform GUI to control instruments compliant with SCPI through VISA
NASA Astrophysics Data System (ADS)
Roach, Eric; Liu, Jing
2015-10-01
In nuclear physics experiments, it is necessary and important to control instruments from a PC, which automates many tasks that require human operations otherwise. Not only does this make long term measurements possible, but it also makes repetitive operations less error-prone. We created a graphical user interface (GUI) to control instruments connected to a PC through RS232, USB, LAN, etc. The GUI is developed using Qt Creator, a cross-platform integrated development environment, which makes it portable to various operating systems, including those commonly used in mobile devices. NI-VISA library is used in the back end so that the GUI can be used to control instruments connected through various I/O interfaces without any modification. Commonly used SCPI commands can be sent to different instruments using buttons, sliders, knobs, and other various widgets provided by Qt Creator. As an example, we demonstrate how we set and fetch parameters and how to retrieve and display data from an Agilent Digital Storage Oscilloscope X3034A with the GUI. Our GUI can be easily used for other instruments compliant with SCPI and VISA with little or no modification.
X-Ray Pulse Selector With 2 ns Lock-in Phase Setting And Stability
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lindenau, B.; Raebiger, J.; Polachowski, S.
2004-05-12
Selector devices, which are based on magnetically suspended, high speed triangular shutter rotors, have been designed and built in cooperation with ESRF, APS, and recently Spring-8 for time resolved studies with isolated x-ray pulses at white beam lines. The x-ray pulse selection is accomplished by means of a beam channel along one of the edges of the triangular rotor, which opens once per revolution. Entrance and exit apertures of the channel can be designed wedge shaped for variable tuning of the channel height between 0.1 mm to 0.9 mm. At the 1 kHz maximum operation frequency of a 220 mmmore » diameter disk with 190 mm channel length, the practicable open times of the channel are demonstrated to range down to 200 ns. The selector drive electronics is directly coupled to the storage ring RF clock for rotational phase control. It allows for continuous selector operation in phase locked mode to the temporal pulse structure of the synchrotron at 2 ns RMS stability. The phase angle between the pulse transmission period and the synchrotron bunch sequence can be adjusted with similar precision for X-ray pulse selection according to the experimental needs. ID09, Michael Wulff ; BioCARS 14-BM, Reinhard Pahl; BL40-XU, Shin-ichi Adachi.« less
Ultralow power switching in a silicon-rich SiNy/SiNx double-layer resistive memory device.
Kim, Sungjun; Chang, Yao-Feng; Kim, Min-Hwi; Bang, Suhyun; Kim, Tae-Hyeon; Chen, Ying-Chen; Lee, Jong-Ho; Park, Byung-Gook
2017-07-26
Here we demonstrate low-power resistive switching in a Ni/SiN y /SiN x /p ++ -Si device by proposing a double-layered structure (SiN y /SiN x ), where the two SiN layers have different trap densities. The LRS was measured to be as low as 1 nA at a voltage of 1 V, because the SiN x layer maintains insulating properties for the LRS. The single-layered device suffers from uncontrollability of the conducting path, accompanied by the inherent randomness of switching parameters, weak immunity to breakdown during the reset process, and a high operating current. On the other hand, for a double-layered device, the effective conducting path in each layer, which can determine the operating current, can be well controlled by the I CC during the initial forming and set processes. A one-step forming and progressive reset process is observed for a low-power mode, which differs from the high-power switching mode that shows a two-step forming and reset process. Moreover, nonlinear behavior in the LRS, whose origin can be attributed to the P-F conduction and F-N tunneling driven by abundant traps in the silicon-rich SiN x layer, would be beneficial for next-generation nonvolatile memory applications by using a conventional passive SiN x layer as an active dielectric.
Propulsion simulator for magnetically-suspended wind tunnel models
NASA Technical Reports Server (NTRS)
Joshi, P. B.; Malonson, M. R.; Sacco, G. P.; Goldey, C. L.; Garbutt, Keith; Goodyer, M.
1992-01-01
In order to demonstrate the measurement of aerodynamic forces/moments, including the effects of exhaust jets in Magnetic Suspension and Balance System (MSBS) wind tunnels, two propulsion simulator models were developed at Physical Sciences Inc. (PSI). Both the small-scale model (1 in. diameter X 8 in. long) and the large-scale model (2.5 in. diameter X 15 in. long) employed compressed, liquefied carbon dioxide as a propellant. The small-scale simulator, made from a highly magnetizable iron alloy, was demonstrated in the 7 in. MSBS wind tunnel at the University of Southampton. It developed a maximum thrust of approximate 1.3 lbf with a 0.098 in. diameter nozzle and 0.7 lbf with a 0.295 in. diameter nozzle. The Southampton MSBS was able to control the simulator at angles-of attack up to 20 deg. The large-scale simulator was demonstrated to operate in both a steady-state and a pulse mode via a miniaturized solinoid valve. It developed a stable and repeatable thrust of 2.75 lbf over a period of 4s and a nozzle pressure ratio (NPR) of 5.
High-Performance LWIR Superlattice Detectors and FPA Based on CBIRD Design
NASA Technical Reports Server (NTRS)
Soibel, Alexander; Nguyen, Jean; Khoshakhlagh, Arezou; Rafol, Sir B.; Hoeglund, Linda; Keo, Sam A.; Mumolo, Jason M.; Liu, John; Liao, Anna; Ting, David Z.-Y.;
2012-01-01
We report our recent efforts on advancing of antimonide superlattice based infrared photodetectors and demonstration of Focal Plane Arrays (FPA) based on a complementary barrier infrared detector (CBIRD) design. By optimizing design and growth condition we succeeded to reduce the operational bias of CBIRD single pixel detector without increase of dark current or degradation of quantum efficiency. We demonstrated a 1024x1024 pixel long-wavelength infrared focal plane array utilizing CBIRD design. An 11.5 ?m cutoff FPA without anti-reflection coating has yielded noise equivalent differential temperature of 53 mK at operating temperature of 80 K, with 300 K background and cold-stop. In addition, we demonstrated 320x256 format FPA based on the n-CBIRD design. The resulting FPAs yielded noise equivalent differential temperature of 26 mK at operating temperature of 80 K, with 300 K background and cold-stop. These results advance state-of-the art of superlattice detectors and demonstrated advantages of CBIRD architecture for realization of FPA.
Zhang, Qiang; Pi, Jingbo; Woods, Courtney G; Andersen, Melvin E
2009-06-15
Hormetic responses to xenobiotic exposure likely occur as a result of overcompensation by the homeostatic control systems operating in biological organisms. However, the mechanisms underlying overcompensation that leads to hormesis are still unclear. A well-known homeostatic circuit in the cell is the gene induction network comprising phase I, II and III metabolizing enzymes, which are responsible for xenobiotic detoxification, and in many cases, bioactivation. By formulating a differential equation-based computational model, we investigated in this study whether hormesis can arise from the operation of this gene/enzyme network. The model consists of two feedback and one feedforward controls. With the phase I negative feedback control, xenobiotic X activates nuclear receptors to induce cytochrome P450 enzyme, which bioactivates X into a reactive metabolite X'. With the phase II negative feedback control, X' activates transcription factor Nrf2 to induce phase II enzymes such as glutathione S-transferase and glutamate cysteine ligase, etc., which participate in a set of reactions that lead to the metabolism of X' into a less toxic conjugate X''. The feedforward control involves phase I to II cross-induction, in which the parent chemical X can also induce phase II enzymes directly through the nuclear receptor and indirectly through transcriptionally upregulating Nrf2. As a result of the active feedforward control, a steady-state hormetic relationship readily arises between the concentrations of the reactive metabolite X' and the extracellular parent chemical X to which the cell is exposed. The shape of dose-response evolves over time from initially monotonically increasing to J-shaped at the final steady state-a temporal sequence consistent with adaptation-mediated hormesis. The magnitude of the hormetic response is enhanced by increases in the feedforward gain, but attenuated by increases in the bioactivation or phase II feedback loop gains. Our study suggests a possibly common mechanism for the hormetic responses observed with many mutagens/carcinogens whose activities require bioactivation by phase I enzymes. Feedforward control, often operating in combination with negative feedback regulation in a homeostatic system, may be a general control theme responsible for steady-state hormesis.
X-31 in flight - Mongoose Maneuver
NASA Technical Reports Server (NTRS)
1995-01-01
Two X-31 Enhanced Fighter Maneuverability (EFM) demonstrators were flown at the Rockwell International facility, Palmdale, California, and the NASA Dryden Flight Research Center, Edwards, California, to obtain data that may apply to the design of highly-maneuverable next-generation fighters. The program had its first flight on October 11, 1990, in Palmdale; it ended in June 1995. The X-31 program demonstrated the value of thrust vectoring (directing engine exhaust flow) coupled with advanced flight control systems, to provide controlled flight during close-in air combat at very high angles of attack. The result of this increased maneuverability is an aircraft with a significant advantage over conventional fighters. 'Angle-of-attack' (alpha) is an engineering term to describe the angle of an aircraft body and wings relative to its actual flight path. During maneuvers, pilots often fly at extreme angles of attack -- with the nose pitched up while the aircraft continues in its original direction. This can lead to loss of control and result in the loss of the aircraft, pilot or both. Three thrust-vectoring paddles made of graphite epoxy mounted on the exhaust nozzle of the X-31 aircraft directed the exhaust flow to provide control in pitch (up and down) and yaw (right and left) to improve control. The paddles can sustain heat of up to 1,500 degrees centigrade for extended periods of time. In addition the X-31 aircraft were configured with movable forward canards and fixed aft strakes. The canards were small wing-like structures set on the wing line between the nose and the leading edge of the wing. The strakes were set on the same line between the trailing edge of the wing and the engine exhaust. Both supplied additional control in tight maneuvering situations. The X-31 research program produced technical data at high angles of attack. This information is giving engineers and aircraft designers a better understanding of aerodynamics, effectiveness of flight controls and thrust vectoring, and airflow phenomena at high angles of attack. This understanding is expected to lead to design methods which provide better maneuverability in future high performance aircraft and make them safer to fly. An international test organization of about 110 people, managed by the Advanced Research Projects Agency (ARPA), conducted the flight operations at NASA Dryden. The ARPA had requested flight research for the X-31 aircraft be moved there in February 1992. In addition to ARPA and NASA, the international test organization (ITO) included the U.S. Navy, the U.S. Air Force, Rockwell International, the Federal Republic of Germany, and Daimler-Benz Aerospace (formerly Messerschmitt-Bolkow-Blohm and Deutsche Aerospace). NASA was responsible for flight research operations, aircraft maintenance, and research engineering once the program moved to Dryden. The No. 1 X-31 aircraft was lost in an accident January 19, 1995. The pilot, Karl Heinz-Lang, of the Federal Republic of Germany, ejected safely before the aircraft crashed in an unpopulated desert area just north of Edwards. The X-31 program logged an X-plane record of 580 flights during the program, including 555 research missions and 21 in Europe for the 1995 Paris Air Show. A total of 14 pilots representing all agencies of the ITO flew the aircraft. In this 36-second clip we see the X-31 performing the 'Mongoose maneuver,' beginning in a tight left hand turn, then pulling the aircraft into a high-angle-of-attack stall/tail-stand maneuver in which the aircraft remains in the vertical for several seconds, then pushes over to resume normal flight. This maneuver is in response to the Sukoi SU-27 'Flanker' test pilot Victor Georgievich Pugachev's 'Cobra maneuver' or 'Pugachev's cobra,' in which the aircraft, like the X-31, is stood on its tail to give the pilot a tactical advantage in air-to-air combat by essentially stopping and pointing the aircraft weapons toward the opponent.
Lee, Taewoo; Park, Junhong; Kwon, Sangil; Lee, Jongtae; Kim, Jeongsoo
2013-09-01
The objective of this study is to quantify the differences in NO(x) emissions between standard and non-standard driving and vehicle operating conditions, and to estimate by how much NO(x) emissions exceed the legislative emission limits under typical Korean road traffic conditions. Twelve Euro 3-5 light-duty diesel vehicles (LDDVs) manufactured in Korea were driven on a chassis dynamometer over the standard New European Driving Cycle (NEDC) and a representative Korean on-road driving cycle (KDC). NO(x) emissions, average speeds and accelerations were calculated for each 1-km trip segment, so called averaging windows. The results suggest that the NO(x) emissions of the tested vehicles are more susceptible to variations in the driving cycles than to those in the operating conditions. Even under comparable operating conditions, the NO(x) control capabilities of vehicles differ from each other, i.e., NO(x) control is weaker for the KDC than for the NEDC. The NO(x) emissions over the KDC for given vehicle operating conditions exceed those over the NEDC by more than a factor of 8. Consequently, on-road NO(x) emission factors are estimated here to exceed the Euro 5 emission limit by up to a factor of 8, 4 and 3 for typical Korean urban, rural, and motorway road traffic conditions, respectively. Our findings support the development of technical regulations for supplementary real-world emission tests for emission certification and the corresponding research actions taken by automotive industries. Copyright © 2013 Elsevier B.V. All rights reserved.
NASA's OCA Mirroring System: An Application of Multiagent Systems in Mission Control
NASA Technical Reports Server (NTRS)
Sierhuis, Maarten; Clancey, William J.; vanHoof, Ron J. J.; Seah, Chin H.; Scott, Michael S.; Nado, Robert A.; Blumenberg, Susan F.; Shafto, Michael G.; Anderson, Brian L.; Bruins, Anthony C.;
2009-01-01
Orbital Communications Adaptor (OCA) Flight Controllers, in NASA's International Space Station Mission Control Center, use different computer systems to uplink, downlink, mirror, archive, and deliver files to and from the International Space Station (ISS) in real time. The OCA Mirroring System (OCAMS) is a multiagent software system (MAS) that is operational in NASA's Mission Control Center. This paper presents OCAMS and its workings in an operational setting where flight controllers rely on the system 24x7. We also discuss the return on investment, based on a simulation baseline, six months of 24x7 operations at NASA Johnson Space Center in Houston, Texas, and a projection of future capabilities. This paper ends with a discussion of the value of MAS and future planned functionality and capabilities.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yi, Di; Flint, Charles L.; Balakrishnan, Purnima P.
Here, perpendicular magnetic anisotropy (PMA) plays a critical role in the development of spintronics, thereby demanding new strategies to control PMA. Here we demonstrate a conceptually new type of interface induced PMA that is controlled by oxygen octahedral rotation. In superlattices comprised of La 1–xSr xMnO 3 and SrIrO 3, we find that all superlattices (0 ≤ x ≤ 1) exhibit ferromagnetism despite the fact that La 1–xSr xMnO 3 is antiferromagnetic for x > 0.5. PMA as high as 4 × 10 6 erg/cm 3 is observed by increasing x and attributed to a decrease of oxygen octahedral rotationmore » at interfaces. We also demonstrate that oxygen octahedral deformation cannot explain the trend in PMA. These results reveal a new degree of freedom to control PMA, enabling discovery of emergent magnetic textures and topological phenomena.« less
Yi, Di; Flint, Charles L.; Balakrishnan, Purnima P.; ...
2017-08-14
Here, perpendicular magnetic anisotropy (PMA) plays a critical role in the development of spintronics, thereby demanding new strategies to control PMA. Here we demonstrate a conceptually new type of interface induced PMA that is controlled by oxygen octahedral rotation. In superlattices comprised of La 1–xSr xMnO 3 and SrIrO 3, we find that all superlattices (0 ≤ x ≤ 1) exhibit ferromagnetism despite the fact that La 1–xSr xMnO 3 is antiferromagnetic for x > 0.5. PMA as high as 4 × 10 6 erg/cm 3 is observed by increasing x and attributed to a decrease of oxygen octahedral rotationmore » at interfaces. We also demonstrate that oxygen octahedral deformation cannot explain the trend in PMA. These results reveal a new degree of freedom to control PMA, enabling discovery of emergent magnetic textures and topological phenomena.« less
Torque test measurement in segmental bone defects using porous calcium phosphate cement implants.
Kroese-Deutman, Henriette C; Wolke, Joop G C; Spauwen, Paul H M; Jansen, John A
2010-10-01
This study was performed to assess the bone healing supporting characteristics of porous calcium phosphate (Ca-P) cement when implanted in a rabbit segmental defect model as well as to determine the reliability of torque testing as a method to verify bone healing. The middiaphyseal radius was chosen as the area to create bilaterally increasing defect sizes (5, 10, and 15 mm), which were either filled with porous Ca-P cement or left open as a control. After 12 weeks of implantation, torque test measurements as well as histological and radiographic evaluation were performed. In two of the open 15 mm control defects, bone bridging was visible at the radiographic and histological evaluation. Bone was observed to be present in all porous Ca-P cement implants (5, 10, and 15 mm defects) after 12 weeks. No significant differences in torque measurements were observed between the 5 and 10 mm filled and open control defects using a t-test. In addition, the mechanical strength of all operated specimens was similar compared with nonoperated bone samples. The torsion data for the 15 mm open defect appeared to be lower compared with the filled 15 mm defect, but no significant difference could be proven. Within the limitation of the study design, porous Ca-P cement implants demonstrated osteoconductive properties and confirmed to be a suitable scaffold material in a weight-bearing situation. Further, the used torque testing method was found to be unreliable for testing the mechanical properties of the healed bone defect.
Deterministic Computer-Controlled Polishing Process for High-Energy X-Ray Optics
NASA Technical Reports Server (NTRS)
Khan, Gufran S.; Gubarev, Mikhail; Speegle, Chet; Ramsey, Brian
2010-01-01
A deterministic computer-controlled polishing process for large X-ray mirror mandrels is presented. Using tool s influence function and material removal rate extracted from polishing experiments, design considerations of polishing laps and optimized operating parameters are discussed
X-31 in flight - Post Stall Maneuver
NASA Technical Reports Server (NTRS)
1995-01-01
Two X-31 Enhanced Fighter Maneuverability (EFM) demonstrators were flown at the Rockwell International facility, Palmdale, California, and the NASA Dryden Flight Research Center, Edwards, California, to obtain data that may apply to the design of highly-maneuverable next-generation fighters. The program had its first flight on October 11, 1990, in Palmdale; it ended in June 1995. The X-31 program demonstrated the value of thrust vectoring (directing engine exhaust flow) coupled with advanced flight control systems, to provide controlled flight during close-in air combat at very high angles of attack. The result of this increased maneuverability is an aircraft with a significant advantage over conventional fighters. 'Angle-of-attack' (alpha) is an engineering term to describe the angle of an aircraft body and wings relative to its actual flight path. During maneuvers, pilots often fly at extreme angles of attack -- with the nose pitched up while the aircraft continues in its original direction. This can lead to loss of control and result in the loss of the aircraft, pilot or both. Three thrust vectoring paddles made of graphite epoxy mounted on the exhaust nozzle of the X-31 aircraft directed the exhaust flow to provide control in pitch (up and down) and yaw (right and left) to improve control. The paddles can sustain heat of up to 1,500 degrees centigrade for extended periods of time. In addition the X-31 aircraft were configured with movable forward canards and fixed aft strakes. The canards were small wing-like structures set on the wing line between the nose and the leading edge of the wing. The strakes were set on the same line between the trailing edge of the wing and the engine exhaust. Both supplied additional control in tight maneuvering situations. The X-31 research program produced technical data at high angles of attack. This information is giving engineers and aircraft designers a better understanding of aerodynamics, effectiveness of flight controls and thrust vectoring, and airflow phenomena at high angles of attack. This understanding is expected to lead to design methods that can provide better maneuverability in future high performance aircraft and make them safer to fly. An international test organization of about 110 people, managed by the Advanced Research Projects Agency (ARPA), conducted the flight operations at NASA Dryden. The ARPA had requested flight research for the X-31 aircraft be moved there in February 1992. In addition to ARPA and NASA, the international test organization (ITO) included the U.S. Navy, the U.S. Air Force, Rockwell International, the Federal Republic of Germany, and Daimler-Benz Aerospace (formerly Messerschmitt-Bolkow-Blohm and Deutsche Aerospace). NASA was responsible for flight research operations, aircraft maintenance, and research engineering once the program moved to Dryden. The No. 1 X-31 aircraft was lost in an accident January 19, 1995. The pilot, Karl Heinz-Lang, of the Federal Republic of Germany, ejected safely before the aircraft crashed in an unpopulated desert area just north of Edwards. The X-31 program logged an X-plane record of 580 flights during the program, including 555 research missions and 21 in Europe for the 1995 Paris Air Show. A total of 14 pilots representing all agencies of the ITO flew the aircraft. This movie clip runs 1 minute, 6 seconds in length and shows the X-31 rotating at takeoff and climbing into a stall maneuver. The aircraft then slides backwards thrust vectoring the tail over the top, turning the stall into a loop in which the aircraft then reverses its heading and resumes level flight.
Silicon based quantum dot hybrid qubits
NASA Astrophysics Data System (ADS)
Kim, Dohun
2015-03-01
The charge and spin degrees of freedom of an electron constitute natural bases for constructing quantum two level systems, or qubits, in semiconductor quantum dots. The quantum dot charge qubit offers a simple architecture and high-speed operation, but generally suffers from fast dephasing due to strong coupling of the environment to the electron's charge. On the other hand, quantum dot spin qubits have demonstrated long coherence times, but their manipulation is often slower than desired for important future applications. This talk will present experimental progress of a `hybrid' qubit, formed by three electrons in a Si/SiGe double quantum dot, which combines desirable characteristics (speed and coherence) in the past found separately in qubits based on either charge or spin degrees of freedom. Using resonant microwaves, we first discuss qubit operations near the `sweet spot' for charge qubit operation. Along with fast (>GHz) manipulation rates for any rotation axis on the Bloch sphere, we implement two independent tomographic characterization schemes in the charge qubit regime: traditional quantum process tomography (QPT) and gate set tomography (GST). We also present resonant qubit operations of the hybrid qubit performed on the same device, DC pulsed gate operations of which were recently demonstrated. We demonstrate three-axis control and the implementation of dynamic decoupling pulse sequences. Performing QPT on the hybrid qubit, we show that AC gating yields π rotation process fidelities higher than 93% for X-axis and 96% for Z-axis rotations, which demonstrates efficient quantum control of semiconductor qubits using resonant microwaves. We discuss a path forward for achieving fidelities better than the threshold for quantum error correction using surface codes. This work was supported in part by ARO (W911NF-12-0607), NSF (PHY-1104660), DOE (DE-FG02-03ER46028), and by the Laboratory Directed Research and Development program at Sandia National Laboratories under contract DE-AC04-94AL85000.
NASA Technical Reports Server (NTRS)
Finch, Thomas W.; Matranga, Gene J.
1959-01-01
The first flight of the North American X-15 research airplane was made on June 8, 1959. This was accomplished after completion of a series of captive flights with the X-15 attached to the B-52 carrier airplane to demonstrate the aerodynamic and systems compatibility of the X-15//B-52 combination and the X-15 subsystem operation. This flight was planned as a glide flight so that the pilot need not be concerned with the propulsion system. Discussions of the launch, low-speed maneuvering, and landing characteristics are presented, and the results are compared with predictions from preflight studies. The launch characteristics were generally satisfactory, and the X-15 vertical tail adequately cleared the B-52 wing cutout. The actual landing pattern and landing characteristics compared favorably with predictions, and the recommended landing technique of lowering the flaps and landing gear at a low altitude appears to be a satisfactory method of landing the X-15 airplane. There was a quantitative correlation between flight-measured and predicted lift-drag-ratio characteristics in the clean configuration and a qualitative correlation in the landing configuration. A longitudinal-controllability problem, which became severe in the landing configuration, was evident throughout the flight and, apparently, was aggravated by the sensitivity of the side-located control stick. In the low-to-moderate angle-of-attack range covered, the longitudinal and directional stability were indicated to be adequate.
Takamatsu, Daiko; Yoneyama, Akio; Asari, Yusuke; Hirano, Tatsumi
2018-02-07
A fundamental understanding of concentrations of salts in lithium-ion battery electrolytes during battery operation is important for optimal operation and design of lithium-ion batteries. However, there are few techniques that can be used to quantitatively characterize salt concentration distributions in the electrolytes during battery operation. In this paper, we demonstrate that in operando X-ray phase imaging can quantitatively visualize the salt concentration distributions that arise in electrolytes during battery operation. From quantitative evaluation of the concentration distributions at steady states, we obtained the salt diffusivities in electrolytes with different initial salt concentrations. Because of no restriction on samples and high temporal and spatial resolutions, X-ray phase imaging will be a versatile technique for evaluating electrolytes, both aqueous and nonaqueous, of many electrochemical systems.
Mission Manager Area of the Spacelab Payload Operations Control Center (SL POCC)
NASA Technical Reports Server (NTRS)
1990-01-01
The primary objective of the STS-35 mission was round the clock observation of the celestial sphere in ultraviolet and X-Ray astronomy with the Astro-1 observatory which consisted of four telescopes: the Hopkins Ultraviolet Telescope (HUT); the Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE); the Ultraviolet Imaging Telescope (UIT); and the Broad Band X-Ray Telescope (BBXRT). The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Teams of controllers and researchers directed on-orbit science operations, sent commands to the spacecraft, received data from experiments aboard the Space Shuttle, adjusted mission schedules to take advantage of unexpected science opportunities or unexpected results, and worked with crew members to resolve problems with their experiments. Pictured is Jack Jones in the Mission Manager Area.
Virtual Deformation Control of the X-56A Model with Simulated Fiber Optic Sensors
NASA Technical Reports Server (NTRS)
Suh, Peter M.; Chin, Alexander W.; Mavris, Dimitri N.
2014-01-01
A robust control law design methodology is presented to stabilize the X-56A model and command its wing shape. The X-56A was purposely designed to experience flutter modes in its flight envelope. The methodology introduces three phases: the controller design phase, the modal filter design phase, and the reference signal design phase. A mu-optimal controller is designed and made robust to speed and parameter variations. A conversion technique is presented for generating sensor strain modes from sensor deformation mode shapes. The sensor modes are utilized for modal filtering and simulating fiber optic sensors for feedback to the controller. To generate appropriate virtual deformation reference signals, rigid-body corrections are introduced to the deformation mode shapes. After successful completion of the phases, virtual deformation control is demonstrated. The wing is deformed and it is shown that angle-ofattack changes occur which could potentially be used to an advantage. The X-56A program must demonstrate active flutter suppression. It is shown that the virtual deformation controller can achieve active flutter suppression on the X-56A simulation model.
Virtual Deformation Control of the X-56A Model with Simulated Fiber Optic Sensors
NASA Technical Reports Server (NTRS)
Suh, Peter M.; Chin, Alexander Wong
2013-01-01
A robust control law design methodology is presented to stabilize the X-56A model and command its wing shape. The X-56A was purposely designed to experience flutter modes in its flight envelope. The methodology introduces three phases: the controller design phase, the modal filter design phase, and the reference signal design phase. A mu-optimal controller is designed and made robust to speed and parameter variations. A conversion technique is presented for generating sensor strain modes from sensor deformation mode shapes. The sensor modes are utilized for modal filtering and simulating fiber optic sensors for feedback to the controller. To generate appropriate virtual deformation reference signals, rigid-body corrections are introduced to the deformation mode shapes. After successful completion of the phases, virtual deformation control is demonstrated. The wing is deformed and it is shown that angle-of-attack changes occur which could potentially be used to an advantage. The X-56A program must demonstrate active flutter suppression. It is shown that the virtual deformation controller can achieve active flutter suppression on the X-56A simulation model.
Flywheel-Powered Mobile X-Ray Generator.
1983-03-18
38 Circuit Description .. . . . . . . . .. 40 0. Digital Tachometer Purpose . . . . . . . . . . . . . . . 47 Operation...47 Circuit Description . . . . . . . . o 47 E. High Tension Transfoner Purpose . . . . . . . . . . . . . . . 51 Operation... Circuit Purpose . . . . . . . . . . . . . . . 54 Operation . . . . . . . . . . . . . . 54 G. Tube Rotor Control Purpose ........ . 57 Operation of Timer
Heilmann, René; Gräfe, Markus; Nolte, Stefan; Szameit, Alexander
2014-01-01
Chip-based photonic quantum computing is an emerging technology that promises much speedup over conventional computers at small integration volumes. Particular interest is thereby given to polarisation-encoded photonic qubits, and many protocols have been developed for this encoding. However, arbitrary wave plate operation on chip are not available so far, preventing from the implementation of integrated universal quantum computing algorithms. In our work we close this gap and present Hadamard, Pauli-X, and rotation gates of high fidelity for photonic polarisation qubits on chip by employing a reorientation of the optical axis of birefringent waveguides. The optical axis of the birefringent waveguide is rotated due to the impact of an artificial stress field created by an additional modification close to the waveguide. By adjusting this length of the defect along the waveguide, the retardation between ordinary and extraordinary field components is precisely tunable including half-wave plate and quarter-wave plate operations. Our approach demonstrates the full range control of orientation and strength of the induced birefringence and thus allows arbitrary wave plate operations without affecting the degree of polarisation or introducing additional losses to the waveguides. The implemented gates are tested with classical and quantum light. PMID:24534893
2000-12-08
With a small stabilization parachute trailing behind, the X-40 sub-scale technology demonstrator is suspended under a U.S. Army CH-47 Chinook cargo helicopter during a captive-carry test flight at NASA's Dryden Flight Research Center, Edwards, California. The captive carry flights are designed to verify the X-40's navigation and control systems, rigging angles for its sling, and stability and control of the helicopter while carrying the X-40 on a tether. Following a series of captive-carry flights, the X-40 made free flights from a launch altitude of about 15,000 feet above ground, gliding to a fully autonomous landing. The X-40 is an unpowered 82 percent scale version of the X-37, a Boeing-developed spaceplane designed to demonstrate various advanced technologies for development of future lower-cost access to space vehicles.
2004-04-15
The wedge-shaped X-33 was a sub-scale technology demonstration prototype of a Reusable Launch Vehicle (RLV). Through demonstration flights and ground research, NASA's X-33 program was to provide the information needed for industry representatives such as Lockheed Martin (builder of the X-33 Venture Star) to decide by the year 2000 whether to proceed with the development of a full-scale, commercial RLV program. This program would dramatically increase reliability and lower the costs of putting a payload into space. This would in turn create new opportunities for space access and significantly improve U.S. economic competitiveness in the worldwide launch marketplace. NASA would be a customer, not the operator in the commercial RLV. The X-33 program was cancelled in 2001.
DOT National Transportation Integrated Search
2008-12-01
Programmable logic controllers (PLCs) were installed at several key ramps with the assistance of the City of Portland and used to capture additional data about ramp operations that are not otherwise logged. The data include the activation and deactiv...
Environmental monitoring for the DOE coolside and LIMB demonstration extension projects
DOE Office of Scientific and Technical Information (OSTI.GOV)
White, T.; Contos, L.; Adams, L.
1992-03-01
The purpose of this document is to present environmental monitoring data collected during the US Department of Energy Limestone Injection Multistage Burner (DOE LIMB) Demonstration Project Extension at the Ohio Edison Edgewater Generating Station in Lorain, Ohio. The DOE project is an extension of the US Environmental Protection Agency's (EPA's) original LIMB Demonstration. The program is operated nuclear DOE's Clean Coal Technology Program of emerging clean coal technologies'' under the categories of in boiler control of oxides of sulfur and nitrogen'' as well as post-combustion clean-up.'' The objective of the LIMB program is to demonstrate the sulfur dioxide (SO{sub 2})more » and nitrogen oxide (NO{sub x}) emission reduction capabilities of the LIMB system. The LIMB system is a retrofit technology to be used for existing coal-fired boilers equipped with electrostatic precipitators (ESPs).« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
White, T.; Contos, L.; Adams, L.
1992-03-01
The purpose of this document is to present environmental monitoring data collected during the US Department of Energy Limestone Injection Multistage Burner (DOE LIMB) Demonstration Project Extension at the Ohio Edison Edgewater Generating Station in Lorain, Ohio. The DOE project is an extension of the US Environmental Protection Agency`s (EPA`s) original LIMB Demonstration. The program is operated nuclear DOE`s Clean Coal Technology Program of ``emerging clean coal technologies`` under the categories of ``in boiler control of oxides of sulfur and nitrogen`` as well as ``post-combustion clean-up.`` The objective of the LIMB program is to demonstrate the sulfur dioxide (SO{sub 2})more » and nitrogen oxide (NO{sub x}) emission reduction capabilities of the LIMB system. The LIMB system is a retrofit technology to be used for existing coal-fired boilers equipped with electrostatic precipitators (ESPs).« less
Revolutionary Concepts for Helicopter Noise Reduction: SILENT Program
NASA Technical Reports Server (NTRS)
Edwards, Bryan; Cox, Charles; Booth, Earl R., Jr. (Technical Monitor)
2002-01-01
As part of a NASA initiative to reduce helicopter main rotor noise, a Phase 1 study has been performed of candidate noise reduction concepts. Both conventional and novel design technologies have been analyzed that reduce the community impact of helicopter operations. In this study the noise reduction potential and design implications are assessed for conventional means of noise reduction, e.g., tip speed reduction, tip shapes and airfoil tailoring, and for two innovative design concepts: modulated blade spacing and x-force control. Main rotor designs that incorporate modulated blade spacing are shown to have reduced peak noise levels in most flight operations. X-force control alters the helicopter's force balance whereby the miss distance between main rotor blades and shed vortices can be controlled. This control provides a high potential to mitigate BVI noise radiation. Each concept is evaluated using best practice design and analysis methods, achieving the study's aim to significantly reduce noise with minimal performance degradation and no vibration increase. It is concluded that a SILENT main rotor design, incorporating the modulated blade spacing concept, offers significantly reduced noise levels and the potential of a breakthrough in how a helicopter's sound is perceived and judged. The SILENT rotor represents a definite advancement in the state-of-the-art and is selected as the design concept for demonstration in Phase 2. A Phase 2 Implementation Plan is developed for whirl cage and wind tunnel evaluations of a scaled model SILENT rotor.
X-Band CubeSat Communication System Demonstration
NASA Technical Reports Server (NTRS)
Altunc, Serhat; Kegege, Obadiah; Bundick, Steve; Shaw, Harry; Schaire, Scott; Bussey, George; Crum, Gary; Burke, Jacob C.; Palo, Scott; O'Conor, Darren
2015-01-01
Today's CubeSats mostly operate their communications at UHF- and S-band frequencies. UHF band is presently crowded, thus downlink communications are at lower data rates due to bandwidth limitations and are unreliable due to interference. This research presents an end-to-end robust, innovative, compact, efficient and low cost S-band uplink and X-band downlink CubeSat communication system demonstration between a balloon and a Near Earth Network (NEN) ground system. Since communication systems serve as umbilical cords for space missions, demonstration of this X-band communication system is critical for successfully supporting current and future CubeSat communication needs. This research has three main objectives. The first objective is to design, simulate, and test a CubeSat S- and X-band communication system. Satellite Tool Kit (STK) dynamic link budget calculations and HFSS Simulations and modeling results have been used to trade the merit of various designs for small satellite applications. S- and X-band antennas have been tested in the compact antenna test range at Goddard Space Flight Center (GSFC) to gather radiation pattern data. The second objective is simulate and test a CubeSat compatible X-band communication system at 12.5Mbps including S-band antennas, X-band antennas, Laboratory for Atmospheric and Space Physics (LASP) /GSFC transmitter and an S-band receiver from TRL-5 to TRL-8 by the end of this effort. Different X-band communication system components (antennas, diplexers, etc.) from GSFC, other NASA centers, universities, and private companies have been investigated and traded, and a complete component list for the communication system baseline has been developed by performing analytical and numerical analysis. This objective also includes running simulations and performing trades between different X-band antenna systems to optimize communication system performance. The final objective is to perform an end-to-end X-band CubeSat communication system demonstration between a balloon and/or a sounding rocket and a Near Earth Network (NEN) ground system. This paper presents CubeSat communication systems simulation results, analysis of X-band and S-band antennas and RF front-end components, transceiver design, analysis and optimization of space-to-ground communication performance, subsystem development, as well as the test results for an end-to-end X-band CubeSat communication system demonstration. The outcome of this work will be used to pave the way for next generation NEN-compatible X-band CubeSat communication systems to support higher data rates with more advanced modulation and forward error correction (FEC) coding schemes, and to support and attract new science missions at lower cost. It also includes an abbreviated concept of operations for CubeSat users to utilize the NEN, starting from first contact with NASA's communication network and continuing through on-orbit operations.
X-33 Simulation Lab and Staff Engineers
NASA Technical Reports Server (NTRS)
1997-01-01
X-33 program engineers at NASA's Dryden Flight Research Center, Edwards, California, monitor a flight simulation of the X-33 Advanced Technology Demonstrator as a 'flight' unfolds. The simulation provided flight trajectory data while flight control laws were being designed and developed. It also provided information which assisted X-33 developer Lockheed Martin in aerodynamic design of the vehicle. The X-33 program was a government/industry effort to design, build and fly a half-scale prototype that was to demonstrate in flight the new technologies needed for Lockheed Martin's proposed full-scale VentureStar Reusable Launch Vehicle. The X-33 was a wedged-shaped subscale technology demonstrator prototype of a potential future Reusable Launch Vehicle (RLV) that Lockheed Martin had dubbed VentureStar. The company had hoped to develop VentureStar early this century. Through demonstration flight and ground research, NASA's X-33 program was intended to provide the information needed for industry representatives such as Lockheed Martin to decide whether to proceed with the development of a full-scale, commercial RLV program. A full-scale, single-stage-to-orbit RLV was intended to dramatically increase reliability and lower costs of putting a pound of payload into space, from the current figure of $10,000 to $1,000. Reducing the cost associated with transporting payloads in Low Earth Orbit (LEO) by using a commercial RLV was to create new opportunities for space access and significantly improve U.S. economic competitiveness in the world-wide launch marketplace. NASA expected to be a customer, not the operator, of the commercial RLV. The X-33 design was based on a lifting body shape with two revolutionary 'linear aerospike' rocket engines and a rugged metallic thermal protection system. The vehicle also had lightweight components and fuel tanks built to conform to the vehicle's outer shape. Time between X-33 flights was normally to have been seven days, but the program hoped to demonstrate a two-day turnaround between flights during the flight-test phase of the program. The X-33 was an unpiloted vehicle that took off vertically like a rocket and landed horizontally like an airplane. It was to reach altitudes of up to 50 miles and high hypersonic speeds. The X-33 program was managed by the Marshall Space Flight Center and was to be launched from a special launch site on Edwards Air Force Base. Due to technical problems with the liquid hydrogen fuel tank, and the resulting cost increase and time delay, the X-33 program was cancelled in February 2001.
Intelligent Command and Control Systems for Satellite Ground Operations
NASA Technical Reports Server (NTRS)
Mitchell, Christine M.
1999-01-01
This grant, Intelligent Command and Control Systems for Satellite Ground Operations, funded by NASA Goddard Space Flight Center, has spanned almost a decade. During this time, it has supported a broad range of research addressing the changing needs of NASA operations. It is important to note that many of NASA's evolving needs, for example, use of automation to drastically reduce (e.g., 70%) operations costs, are similar requirements in both government and private sectors. Initially the research addressed the appropriate use of emerging and inexpensive computational technologies, such as X Windows, graphics, and color, together with COTS (commercial-off-the-shelf) hardware and software such as standard Unix workstations to re-engineer satellite operations centers. The first phase of research supported by this grant explored the development of principled design methodologies to make effective use of emerging and inexpensive technologies. The ultimate performance measures for new designs were whether or not they increased system effectiveness while decreasing costs. GT-MOCA (The Georgia Tech Mission Operations Cooperative Associate) and GT-VITA (Georgia Tech Visual and Inspectable Tutor and Assistant), whose latter stages were supported by this research, explored model-based design of collaborative operations teams and the design of intelligent tutoring systems, respectively. Implemented in proof-of-concept form for satellite operations, empirical evaluations of both, using satellite operators for the former and personnel involved in satellite control operations for the latter, demonstrated unequivocally the feasibility and effectiveness of the proposed modeling and design strategy underlying both research efforts. The proof-of-concept implementation of GT-MOCA showed that the methodology could specify software requirements that enabled a human-computer operations team to perform without any significant performance differences from the standard two-person satellite operations team. GT-VITA, using the same underlying methodology, the operator function model (OFM), and its computational implementation, OFMspert, successfully taught satellite control knowledge required by flight operations team members. The tutor structured knowledge in three ways: declarative knowledge (e.g., What is this? What does it do?), procedural knowledge, and operational skill. Operational skill is essential in real-time operations. It combines the two former knowledge types, assisting a student to use them effectively in a dynamic, multi-tasking, real-time operations environment. A high-fidelity simulator of the operator interface to the ground control system, including an almost full replication of both the human-computer interface and human interaction with the dynamic system, was used in the GT-MOCA and GT-VITA evaluations. The GT-VITA empirical evaluation, conducted with a range of'novices' that included GSFC operations management, GSFC operations software developers, and new flight operations team members, demonstrated that GT-VITA effectively taught a wide range of knowledge in a succinct and engaging manner.
Study of Increasing Lead Times in Major Weapon Systems Acquisition.
1982-07-31
Conduit Covers X X X Connectors, Electrical X X X X X Control Systems (Auto- mated, Boiler) X Davit, Boat, Power- Opera.ted X Diodes X X X X A iX...tubes. Other end uses include washers in computer equipment, electrical insulators in motors and generators, and retardation plates in lasers . Supply...relays, electron tubes, printed circuits, and resistors. Platinum is also used in dentistry and for jewelry. Supply, A small amount of platinum (less
Micromirror-based manipulation of synchrotron x-ray beams
NASA Astrophysics Data System (ADS)
Walko, D. A.; Chen, Pice; Jung, I. W.; Lopez, D.; Schwartz, C. P.; Shenoy, G. K.; Wang, Jin
2017-08-01
Synchrotron beamlines typically use macroscopic, quasi-static optics to manipulate x-ray beams. We present the use of dynamic microelectromechanical systems-based optics (MEMS) to temporally modulate synchrotron x-ray beams. We demonstrate this concept using single-crystal torsional MEMS micromirrors oscillating at frequencies of 75 kHz. Such a MEMS micromirror, with lateral dimensions of a few hundred micrometers, can interact with x rays by operating in grazing-incidence reflection geometry; x rays are deflected only when an x-ray pulse is incident on the rotating micromirror under appropriate conditions, i.e., at an angle less than the critical angle for reflectivity. The time window for such deflections depends on the frequency and amplitude of the MEMS rotation. We demonstrate that reflection geometry can produce a time window of a few microseconds. We further demonstrate that MEMS optics can isolate x rays from a selected synchrotron bunch or group of bunches. With ray-trace simulations we explain the currently achievable time windows and suggest a path toward improvements.
2000-12-08
A U.S. Army CH-47 Chinook helicopter slowly lowers the X-40 sub-scale technology demonstrator to the ground under the watchful eyes of ground crew at the conclusion of a captive-carry test flight at NASA's Dryden Flight Research Center, Edwards, California. Several captive-carry flights were conducted to check out all operating systems and procedures before the X-40 made its first free flight at Edwards, gliding to a fully-autonomous approach and landing on the Edwards runway. The X-40 is an unpowered 82 percent scale version of the X-37, a Boeing-developed spaceplane designed to demonstrate various advanced technologies for development of future lower-cost access to space vehicles. Flight tests of the X-40 are designed to reduce the risks associated with research flights of the larger, more complex X-37.
Fast, Massively Parallel Data Processors
NASA Technical Reports Server (NTRS)
Heaton, Robert A.; Blevins, Donald W.; Davis, ED
1994-01-01
Proposed fast, massively parallel data processor contains 8x16 array of processing elements with efficient interconnection scheme and options for flexible local control. Processing elements communicate with each other on "X" interconnection grid with external memory via high-capacity input/output bus. This approach to conditional operation nearly doubles speed of various arithmetic operations.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yi, Di; Flint, Charles L.; Balakrishnan, Purnima P.
Perpendicular magnetic anisotropy (PMA) plays a critical role in the development of spintronics, thereby demanding new strategies to control PMA. Here we demonstrate a conceptually new type of interface induced PMA that is controlled by oxygen octahedral rotation. In superlattices comprised of La1-xSrxMnO3 and SrIrO3, we find that all superlattices (0<=x<=1) exhibit ferromagnetism despite the fact that La1-xSrxMnO3 is antiferromagnetic for x>0.5. PMA as high as 4×10^6 erg/cm^3 is observed by increasing x and attributed to a decrease of oxygen octahedral rotation at interfaces. We also demonstrate that oxygen octahedral deformation cannot explain the trend in PMA. These results revealmore » a new degree of freedom to control PMA, enabling discovery of emergent magnetic textures and topological phenomena.« less
NASA Technical Reports Server (NTRS)
Notardonato, William; Fesmire, James; Swanger, Adam; Jumper, Kevin; Johnson, Wesley; Tomsik, Thomas
2017-01-01
GODU-LH2 system has successfully met all test objectives at the 33%, 67%, and 100% tank fill level. Complete control over the state of the fluid has been demonstrated using Integrated Refrigeration and Storage (IRAS). Almost any desired point along the H2saturation curve can essentially be "dialed in" and maintained indefinitely. System can also be used to produce densified hydrogen in large quantities to the triple point. Exploring multiple technology infusion paths. Studying implementation of IRAS technology into new LH2sphere for EM-2 at LC39B. Technical interchange also occurring with STMD, LSP, ULA, DoE, KIST, Kawasaki, Shell Oil, SpaceX, US Coast Guard, and Virgin Galactic.
1990-12-04
The primary objective of the STS-35 mission was round the clock observation of the celestial sphere in ultraviolet and X-Ray astronomy with the Astro-1 observatory which consisted of four telescopes: the Hopkins Ultraviolet Telescope (HUT); the Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE); the Ultraviolet Imaging Telescope (UIT); and the Broad Band X-Ray Telescope (BBXRT). The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Teams of controllers and researchers directed on-orbit science operations, sent commands to the spacecraft, received data from experiments aboard the Space Shuttle, adjusted mission schedules to take advantage of unexpected science opportunities or unexpected results, and worked with crew members to resolve problems with their experiments. Due to loss of data used for pointing and operating the ultraviolet telescopes, MSFC ground teams were forced to aim the telescopes with fine tuning by the flight crew. This photo captures the activity of WUPPE (Wisconsin Ultraviolet Photo-Polarimeter Experiment) data review at the Science Operations Area during the mission. This image shows mission activities at the Broad Band X-Ray Telescope (BBXRT) Work Station in the Science Operations Area (SOA).
Novel x-ray silicon detector for 2D imaging and high-resolution spectroscopy
NASA Astrophysics Data System (ADS)
Castoldi, Andrea; Gatti, Emilio; Guazzoni, Chiara; Longoni, Antonio; Rehak, Pavel; Strueder, Lothar
1999-10-01
A novel x-ray silicon detector for 2D imaging has been recently proposed. The detector, called Controlled-Drift Detector, is operated in integrate-readout mode. Its basic feature is the fast transport of the integrated charge to the output electrode by means of a uniform drift field. The drift time of the charge packet identifies the pixel of incidence. A new architecture to implement the Controlled- Drift Detector concept will be presented. The potential wells for the integration of the signal charge are obtained by means of a suitable pattern of deep n-implants and deep p-implants. During the readout mode the signal electrons are transferred in the drift channel that flanks each column of potential wells where they drift towards the collecting electrode at constant velocity. The first experimental measurements demonstrate the successful integration, transfer and drift of the signal electrons. The low output capacitance of the readout electrode together with the on- chip front-end electronics allows high resolution spectroscopy of the detected photons.
Continuation of research into software for space operations support, volume 1
NASA Technical Reports Server (NTRS)
Collier, Mark D.; Killough, Ronnie; Martin, Nancy L.
1990-01-01
A prototype workstation executive called the Hardware Independent Software Development Environment (HISDE) was developed. Software technologies relevant to workstation executives were researched and evaluated and HISDE was used as a test bed for prototyping efforts. New X Windows software concepts and technology were introduced into workstation executives and related applications. The four research efforts performed included: (1) Research into the usability and efficiency of Motif (an X Windows based graphic user interface) which consisted of converting the existing Athena widget based HISDE user interface to Motif demonstrating the usability of Motif and providing insight into the level of effort required to translate an application from widget to another; (2) Prototype a real time data display widget which consisted of research methods for and prototyping the selected method of displaying textual values in an efficient manner; (3) X Windows performance evaluation which consisted of a series of performance measurements which demonstrated the ability of low level X Windows to display textural information; (4) Convert the Display Manager to X Window/Motif which is the application used by NASA for data display during operational mode.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-01-15
... Lightering Operations. Since there will be no new VOC controls for point sources, non-point source sector... equivalent to 1.52 x 1.74 = 2.64 tpd NO X reduction shortfall. Delaware has implemented numerous controls... achieved ``as expeditious as practicable.'' Control measures under RACT constitute a major group of RACM...
Ground crewmen help guide the alignment of the X-40A as the experimental craft is gently lowered to
NASA Technical Reports Server (NTRS)
2000-01-01
Ground crewmen help guide the alignment of the X-40 technology demonstrator as the experimental craft is gently lowered to the ground by a U.S. Army CH-47 Chinook cargo helicopter following a captive-carry test flight at NASA's Dryden Flight Research Center, Edwards, California. The X-40 is an unpowered 82 percent scale version of the X-37, a Boeing-developed spaceplane designed to demonstrate various advanced technologies for development of future lower-cost access to space vehicles. The X-37 will be carried into space aboard a space shuttle and then released to perform various maneuvers and a controlled re-entry through the Earth's atmosphere to an airplane-style landing on a runway, controlled entirely by pre-programmed computer software. Following a series of captive-carry flights, the X-40 made several free flights from a launch altitude of about 15,000 feet above ground, gliding to a fully autonomous landing. The captive carry flights helped verify the X-40's navigation and control systems, rigging angles for its sling, and stability and control of the helicopter while carrying the X-40 on a tether.
Digital optical interconnects for photonic computing
NASA Astrophysics Data System (ADS)
Guilfoyle, Peter S.; Stone, Richard V.; Zeise, Frederick F.
1994-05-01
A 32-bit digital optical computer (DOC II) has been implemented in hardware utilizing 8,192 free-space optical interconnects. The architecture exploits parallel interconnect technology by implementing microcode at the primitive level. A burst mode of 0.8192 X 1012 binary operations per sec has been reliably demonstrated. The prototype has been successful in demonstrating general purpose computation. In addition to emulating the RISC instruction set within the UNIX operating environment, relational database text search operations have been implemented on DOC II.
ERIC Educational Resources Information Center
Stefani, R. T.
This document describes the design of an automatic guidance and control system for a passenger car. A simulation of that system is presented. Analog outputs are provided which compare human operator control to automatic control. One human control possibility is to provide the operator with sufficient feedback information that resulting performance…
2009-10-26
Mission managers, from left, NASA Constellation Program manager Jeff Hanley, Ares I-X Launch Director Ed Mango, Ares I-X mission manager Bob Ess, Ground Operations Manager Philip "Pepper" Phillips, review the latest data in Firing Room One of the Launch Control Center (LCC) at the Kennedy Space Center during the launch countdown of the Ares I-X rocket in Cape Canaveral, Fla., Tuesday, Oct. 27, 2009. The flight test of Ares I-X will provide NASA with an early opportunity to test and prove flight characteristics, hardware, facilities and ground operations associated with the Ares I. Photo Credit: (NASA/Bill Ingalls)
2009-10-26
Mission managers, from left, NASA Ares I-X Assistant Launch Director Pete Nickolenko, Ground Operations Manager Philip "Pepper" Phillips, Ares I-X Launch Director Ed Mango, and Constellation Program manager Jeff Hanley review the latest weather radar from Firing Room One of the Launch Control Center (LCC) at the Kennedy Space Center during the launch countdown of the Ares I-X rocket in Cape Canaveral, Fla., Tuesday, Oct. 27, 2009. The flight test of Ares I-X will provide NASA with an early opportunity to test and prove flight characteristics, hardware, facilities and ground operations associated with the Ares I. Photo Credit: (NASA/Bill Ingalls)
Hot electron light emission in gallium arsenide/aluminium(x) gallium(1-x) arsenic heterostructures
NASA Astrophysics Data System (ADS)
Teke, Ali
In this thesis we have demonstrated the operation of a novel tunable wavelength surface light emitting device. The device is based on a p-GaAs, and n-Ga1- xAlxAs heterojunction containing an inversion layer on the p- side, and GaAs quantum wells on the n- side, and, is referred to as HELLISH-2 (Hot Electron Light Emitting and Lasing in Semiconductor Heterostructure-Type 2). The devices utilise hot electron longitudinal transport and, therefore, light emission is independent of the polarity of the applied voltage. The wavelength of the emitted light can be tuned with the applied bias from GaAs band-to-band transition in the inversion layer to e1-hh1 transition in the quantum wells. In this work tunable means that the device can be operated at either single or multiple wavelength emission. The operation of the device requires only two diffused in point contacts. In this project four HELLISH-2 samples coded as ES1, ES2, ES6 and QT919 have been studied. First three samples were grown by MBE and the last one was grown by MOVPE techniques. ES1 was designed for single and double wavelength operation. ES2 was a control sample used to compare our results with previous work on HELLISH-2 and ES6 was designed for single, double and triple wavelength operation. Theoretical modelling of the device operation was carried out and compared with the experimental results. HELLISH-2 structure was optimised for low threshold and high efficiency operation as based on our model calculations. The last sample QT919 has been designed as an optimised device for single and double wavelength operation like ES1. HELLISH-2 has a number of advantages over the conventional light emitters, resulting in some possible applications, such as light logic gates and wavelength division multiplexing in optoelectronic.
Qiu, Jingjing; Hajibabaei, Hamed; Nellist, Michael R.; ...
2017-08-17
Electrocatalysts improve the efficiency of light-absorbing semiconductor photoanodes driving the oxygen evolution reaction, but the precise function(s) of the electrocatalysts remains unclear. We directly measure, for the first time, the interface carrier transport properties of a prototypical visible-light-absorbing semiconductor, α-Fe 2O 3, in contact with one of the fastest known water oxidation catalysts, Ni 0.8Fe 0.2O x, by directly measuring/controlling the current and/or voltage at the Ni 0.8Fe 0.2O x catalyst layer using a second working electrode. The measurements demonstrate that the majority of photogenerated holes in α-Fe 2O 3 directly transfer to the catalyst film over a wide rangemore » of conditions and that the Ni 0.8Fe 0.2O x is oxidized by photoholes to an operating potential sufficient to drive water oxidation at rates that match the photocurrent generated by the α-Fe 2O 3. The Ni 0.8Fe 0.2O x therefore acts as both a hole-collecting contact and a catalyst for the photoelectrochemical water oxidation process. Separate measurements show that the illuminated junction photovoltage across the α-Fe 2O 3|Ni 0.8Fe 0.2O x interface is significantly decreased by the oxidation of Ni 2+ to Ni 3+ and the associated increase in the Ni 0.8Fe 0.2O x electrical conductivity. Finally, in sum, the results illustrate the underlying operative charge-transfer and photovoltage generation mechanisms of catalyzed photoelectrodes, thus guiding their continued improvement.« less
X-33 Simulation Flown by Steve Ishmael
NASA Technical Reports Server (NTRS)
1997-01-01
Steve Ishmael flies a simulation of the X-33 Advanced Technology Demonstrator at NASA's Dryden Flight Research Center, Edwards, California. This simulation was used to provide flight trajectory data while flight control laws were being designed and developed, as well as to provide aerodynamic design information to X-33 developer Lockheed Martin. The X-33 program was a government/industry effort to design, build and fly a half-scale prototype that was to have demonstrated in flight the new technologies needed for the proposed Lockheed Martin full-scale VentureStar Reusable Launch Vehicle. The X-33 was a wedged-shaped subscale technology demonstrator prototype of a potential future Reusable Launch Vehicle (RLV) that Lockheed Martin had dubbed VentureStar. The company had hoped to develop VentureStar early this century. Through demonstration flight and ground research, NASA's X-33 program was to provide the information needed for industry representatives such as Lockheed Martin to decide whether to proceed with the development of a full-scale, commercial RLV program. A full-scale, single-stage-to-orbit RLV was to have dramatically increased reliability and lowered the costs of putting a pound of payload into space, from the current figure of $10,000 to $1,000. Reducing the cost associated with transporting payloads in Low Earth Orbit (LEO) by using a commercial RLV was to have created new opportunities for space access and significantly improved U.S. economic competitiveness in the world-wide launch marketplace. NASA expected to be a customer, not the operator, of the commercial RLV. The X-33 design was based on a lifting body shape with two revolutionary 'linear aerospike' rocket engines and a rugged metallic thermal protection system. The vehicle also had lightweight components and fuel tanks built to conform to the vehicle's outer shape. Time between X-33 flights was normally to have been seven days, but the program hoped to demonstrate a two-day turnaround between flights during the flight-test phase of the program. The X-33 was to have been an unpiloted vehicle that took off vertically like a rocket and landed horizontally like an airplane. It was to have reached altitudes of up to 50 miles and high hypersonic speeds. The X-33 program was managed by the Marshall Space Flight Center and was to have been launched at a special launch site on Edwards Air Force Base. Due to technical problems with the liquid hydrogen tank and the resulting cost increase and time delay, the X-33 program was cancelled in February 2001.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
AQUATECH Systems, a business unit of Allied-Signal Inc., proposes to demonstrate the technical viability and cost effectiveness of the SOXAL process a combined SO{sub x}/NO{sub x} control process on a 3 MW equivalent flue gas slip stream from Niagara Mohawk Power Corporation, Dunkirk Steam Station Boiler No. 4, a coal fired boiler. The SOXAL process combines 90+% sulfur dioxide removal from the flue gas using a sodium based scrubbing solution and regeneration of the spent scrubbing liquor using AQUATECH Systems` proprietary bipolar membrane technology. This regeneration step recovers a stream of sulfur dioxide suitable for subsequent processing to salable sulfurmore » or sulfuric acid. Additionally 90+% control of NO{sub x} gases can be achieved in combination with conventional urea/methanol injection of NO{sub 2} gas into the duct. The SOXAL process is applicable to both utility and industrial scale boilers using either high or low sulfur coal. The SOXAL demonstration Program began September 10, 1991 and is approximately 22 months in duration.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
AQUATECH Systems a business unit of Allied-Signal Inc., proposes to demonstrate the technical viability and cost effectiveness of the SOXAL process a combined SO{sub x}/NO{sub x} control process on a 2--3 MW equivalent flue gas slip stream from Niagara Mohawk Power Corporation, Dunkirk Steam Station Boiler {number_sign}4, a coal fired boiler. The SOXAL process combines 90+% sulfur dioxide removal from the flue gas using a sodium based scrubbing solution and regeneration of the spent scrubbing liquor using AQUATECH Systems` proprietary bipolar membrane technology. This regeneration step recovers a stream of sulfur dioxide suitable for subsequent processing to salable sulfur ormore » sulfuric acid. Additionally 90+% control of NO{sub x} gases can be achieved in combination with conventional urea/methanol injection of NO{sub 2} gas into the duct. The SOXAL process is applicable to both utility and industrial scale boilers using either high or low sulfur coal. The SOXAL Demonstration Program began September 10, 1991 and is approximately 22 months in duration.« less
Liu, Zhihua; Ge, Yunshan; Johnson, Kent C; Shah, Asad Naeem; Tan, Jianwei; Wang, Chu; Yu, Linxiao
2011-03-15
On-road measurement is an effective method to investigate real-world emissions generated from vehicles and estimate the difference between engine certification cycles and real-world operating conditions. This study presents the results of on-road measurements collected from urban buses which propelled by diesel engine in Beijing city. Two widely used Euro III emission level buses and two Euro IV emission level buses were chosen to perform on-road emission measurements using portable emission measurement system (PEMS) for gaseous pollutant and Electric Low Pressure Impactor (ELPI) for particulate matter (PM) number emissions. The results indicate that considerable discrepancies of engine operating conditions between real-world driving cycles and engine certification cycles have been observed. Under real-world operating conditions, carbon monoxide (CO) and hydrocarbon (HC) emissions can easily meet their respective regulations limits, while brake specification nitrogen oxide (bsNO(x)) emissions present a significant deviation from its corresponding limit. Compared with standard limits, the real-world bsNO(x) emission of the two Euro III emission level buses approximately increased by 60% and 120% respectively, and bsNO(x) of two Euro IV buses nearly twice standard limits because Selective Catalytic Reduction (SCR) system not active under low exhaust temperature. Particle mass were estimated via particle size distribution with the assumption that particle density and diameter is liner. The results demonstrate that nanometer size particulate matter make significant contribution to total particle number but play a minor role to total particle mass. It is suggested that specific certified cycle should be developed to regulate bus engines emissions on the test bench or use PEMS to control the bus emissions under real-world operating conditions. Copyright © 2010 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1992-05-01
The objective of this project is to demonstrate and evaluate commercially available Selective Catalytic Reduction (SCR) catalysts from US, Japanese and European catalyst suppliers on a high-sulfur US coal-fired boiler. SCR is a post-combustion nitrogen oxide (NO{sub x}) control technology that involves injecting ammonia into the flue gas generated from coal combustion in an electric utility boiler. The flue gas containing ammonia is then passed through a reactor that contains a specialized catalyst. In the presence of the catalyst, the amonia reacts with NO{sub x} to convert it to nitrogen and water vapor. Although SCR is widely practiced in Japanmore » and Europe, there are numerous technical uncertainties associated with applying SCR to US coals. These uncertainties include: (1) potential catalyst deactivation due to poisoning by trace metal species present in US coals that are not present in other fuels. (2) performance of the technology and effects on the balance-of-plant equipment in the presence of high amounts of SO, and SO{sub 3}. (3) performance of a wide variety of SCR catalyst compositions, geometries and methods of manufacture under typical high-sulfur coal-fired utility operating conditions. These uncertainties will be explored by constructing a series of small-scale SCR reactors and simultaneously exposing different SCR catalysts to flue gas derived from the combustion of high sulfur US coal. The demonstration will be performed at Gulf Power Company's Plant Crist Unit No. 5 (75 MW capacity) near Pensacola, Florida. The project will be funded by the US Department of Energy (DOE), Southern Company Services, Inc. (SCS on behalf of the entire Southern electric system), and the Electric Power Research Institute.« less
NASA Astrophysics Data System (ADS)
Schimert, Thomas R.; Ratcliff, David D.; Brady, John F., III; Ropson, Steven J.; Gooch, Roland W.; Ritchey, Bobbi; McCardel, P.; Rachels, K.; Wand, Marty; Weinstein, M.; Wynn, John
1999-07-01
Low power and low cost are primary requirements for an imaging infrared camera used in unattended ground sensor arrays. In this paper, an amorphous silicon (a-Si) microbolometer-based uncooled infrared camera technology offering a low cost, low power solution to infrared surveillance for UGS applications is presented. A 15 X 31 micro infrared camera (MIRC) has been demonstrated which exhibits an f/1 noise equivalent temperature difference sensitivity approximately 67 mK. This sensitivity has been achieved without the use of a thermoelectric cooler for array temperature stabilization thereby significantly reducing the power requirements. The chopperless camera is capable of operating from snapshot mode (1 Hz) to video frame rate (30 Hz). Power consumption of 0.4 W without display, and 0.75 W with display, respectively, has been demonstrated at 30 Hz operation. The 15 X 31 camera demonstrated exhibits a 35 mm camera form factor employing a low cost f/1 singlet optic and LED display, as well as low cost vacuum packaging. A larger 120 X 160 version of the MIRC is also in development and will be discussed. The 120 X 160 MIRC exhibits a substantially smaller form factor and incorporates all the low cost, low power features demonstrated in the 15 X 31 MIRC prototype. In this paper, a-Si microbolometer technology for the MIRC will be presented. Also, the key features and performance parameters of the MIRC are presented.
X-33 Reusable Launch Vehicle (RLV) Liftoff
NASA Technical Reports Server (NTRS)
2004-01-01
The wedge-shaped X-33 was a sub-scale technology demonstration prototype of a Reusable Launch Vehicle (RLV). Through demonstration flights and ground research, NASA's X-33 program was to provide the information needed for industry representatives such as Lockheed Martin (builder of the X-33 Venture Star) to decide by the year 2000 whether to proceed with the development of a full-scale, commercial RLV program. This program would dramatically increase reliability and lower the costs of putting a payload into space. This would in turn create new opportunities for space access and significantly improve U.S. economic competitiveness in the worldwide launch marketplace. NASA would be a customer, not the operator in the commercial RLV. The X-33 program was cancelled in 2001.
Boriboonsomsin, Kanok; Durbin, Thomas; Scora, George; Johnson, Kent; Sandez, Daniel; Vu, Alexander; Jiang, Yu; Burnette, Andrew; Yoon, Seungju; Collins, John; Dai, Zhen; Fulper, Carl; Kishan, Sandeep; Sabisch, Michael; Jackson, Doug
2018-09-01
On-road heavy-duty diesel vehicles are a major contributor of oxides of nitrogen (NO x ) emissions. In the US, many heavy-duty diesel vehicles employ selective catalytic reduction (SCR) technology to meet the 2010 emission standard for NO x . Typically, SCR needs to be at least 200°C before a significant level of NO x reduction is achieved. However, this SCR temperature requirement may not be met under some real-world operating conditions, such as during cold starts, long idling, or low speed/low engine load driving activities. The frequency of vehicle operation with low SCR temperature varies partly by the vehicle's vocational use. In this study, detailed vehicle and engine activity data were collected from 90 heavy-duty vehicles involved in a range of vocations, including line haul, drayage, construction, agricultural, food distribution, beverage distribution, refuse, public work, and utility repair. The data were used to create real-world SCR temperature and engine load profiles and identify the fraction of vehicle operating time that SCR may not be as effective for NO x control. It is found that the vehicles participated in this study operate with SCR temperature lower than 200°C for 11-70% of the time depending on their vocation type. This implies that real-world NO x control efficiency could deviate from the control efficiency observed during engine certification. Copyright © 2018 Elsevier B.V. All rights reserved.
The X-33 range Operations Control Center
NASA Technical Reports Server (NTRS)
Shy, Karla S.; Norman, Cynthia L.
1998-01-01
This paper describes the capabilities and features of the X-33 Range Operations Center at NASA Dryden Flight Research Center. All the unprocessed data will be collected and transmitted over fiber optic lines to the Lockheed Operations Control Center for real-time flight monitoring of the X-33 vehicle. By using the existing capabilities of the Western Aeronautical Test Range, the Range Operations Center will provide the ability to monitor all down-range tracking sites for the Extended Test Range systems. In addition to radar tracking and aircraft telemetry data, the Telemetry and Radar Acquisition and Processing System is being enhanced to acquire vehicle command data, differential Global Positioning System corrections and telemetry receiver signal level status. The Telemetry and Radar Acquisition Processing System provides the flexibility to satisfy all X-33 data processing requirements quickly and efficiently. Additionally, the Telemetry and Radar Acquisition Processing System will run a real-time link margin analysis program. The results of this model will be compared in real-time with actual flight data. The hardware and software concepts presented in this paper describe a method of merging all types of data into a common database for real-time display in the Range Operations Center in support of the X-33 program. All types of data will be processed for real-time analysis and display of the range system status to ensure public safety.
NASA Technical Reports Server (NTRS)
Quast, Peter; Tung, Frank; West, Mark; Wider, John
2000-01-01
The Chandra X-ray Observatory (CXO, formerly AXAF) is the third of the four NASA great observatories. It was launched from Kennedy Space Flight Center on 23 July 1999 aboard the Space Shuttle Columbia and was successfully inserted in a 330 x 72,000 km orbit by the Inertial Upper Stage (IUS). Through a series of five Integral Propulsion System burns, CXO was placed in a 10,000 x 139,000 km orbit. After initial on-orbit checkout, Chandra's first light images were unveiled to the public on 26 August, 1999. The CXO Pointing Control and Aspect Determination (PCAD) subsystem is designed to perform attitude control and determination functions in support of transfer orbit operations and on-orbit science mission. After a brief description of the PCAD subsystem, the paper highlights the PCAD activities during the transfer orbit and initial on-orbit operations. These activities include: CXO/IUS separation, attitude and gyro bias estimation with earth sensor and sun sensor, attitude control and disturbance torque estimation for delta-v burns, momentum build-up due to gravity gradient and solar pressure, momentum unloading with thrusters, attitude initialization with star measurements, gyro alignment calibration, maneuvering and transition to normal pointing, and PCAD pointing and stability performance.
Electrolytic hydriding of LaFe(13-x)Si(x) alloys for energy efficient magnetic cooling.
Lyubina, Julia; Hannemann, Ullrich; Ryan, Mary P; Cohen, Lesley F
2012-04-17
An effective, low-temperature and readily available electrochemical method for tuning the operation temperature of LaFe(13-x)Si(x)-type alloys is demonstrated. Electrolytically hydrided materials have the same high level magnetic properties as in high temperature gas-phase processed materials and offer an advantage of higher hydrogen absorption rate in the ferromagnetic state. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
X-37 Space Vehicle: Starting a New Age in Space Control?
NASA Astrophysics Data System (ADS)
Jameson, Austin D.
2001-04-01
The U.S. can no longer rely on the "space as a sanctuary" policy, initiated by the Eisenhower Administration, to continue to exploit space for economic and military advantages. The X-37 space maneuvering vehicle demonstrator is an opportunity for the U.S. to begin to develop methods to more strategically defend and control the space environment. The X-37 is the first of NASA's x-vehicles intended to demonstrate leading edge technologies in orbit. This prototype space maneuvering vehicle co-sponsored by NASA, the Air Force and the Boeing Company is being designed to achieve the goals of reducing the cost to access space from 10,000 to 1000 per pound while improving reliability. The current project is funded to build an autonomous space maneuvering vehicle with on-orbit testing scheduled in 2002, The X-37 is an unmanned space plane that can carry a payload, and can conduct missions while orbiting, loitering, or rendezvousing with objects in space and then autonomously return to earth by landing on a conventional runway. If the Air Force develops the X-37 to its full potential the system could strategically support each of the Air Force's four space mission areas of force enhancement, space support, space control, and force application. Transition of the space maneuvering demonstrator into a space control platform will require a change in national policy. Capitalizing on the lessons from NASA's x-vehicles and partnering with the commercial sector can potentially save costs and shorten the development of a viable space platform that could be used for space control. Strategic development and funded evolution of the X-37 space vehicle is an immediate, tangible step the United States can take to actively pursue a more aggressive program to respond to threats in the space arena.
The Surge Capacity for People in Emergencies (SCOPE) study in Australasian hospitals.
Traub, Matthias; Bradt, David A; Joseph, Anthony P
2007-04-16
To measure physical assets in Australasian hospitals required for the management of mass casualties as a result of terrorism or natural disasters. A cross-sectional survey of Australian and New Zealand hospitals. All emergency department directors of Australasian College for Emergency Medicine (ACEM)-accredited hospitals, as well as private and non-ACEM accredited emergency departments staffed by ACEM Fellows in metropolitan Sydney. Numbers of operating theatres, intensive care unit (ICU) beds and x-ray machines; state of preparedness using benchmarks defined by the Centers for Disease Control and Prevention in the United States. We found that 61%-82% of critically injured patients would not have immediate access to operative care, 34%-70% would have delayed access to an ICU bed, and 42% of the less critically injured would have delayed access to x-ray facilities. Our study demonstrates that physical assets in Australasian public hospitals do not meet US hospital preparedness benchmarks for mass casualty incidents. We recommend national agreement on disaster preparedness benchmarks and periodic publication of hospital performance indicators to enhance disaster preparedness.
1990-12-07
The primary objective of the STS-35 mission was round the clock observation of the celestial sphere in ultraviolet and X-Ray astronomy with the Astro-1 observatory which consisted of four telescopes: the Hopkins Ultraviolet Telescope (HUT); the Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE); the Ultraviolet Imaging Telescope (UIT); and the Broad Band X-Ray Telescope (BBXRT). The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Teams of controllers and researchers directed on-orbit science operations, sent commands to the spacecraft, received data from experiments aboard the Space Shuttle, adjusted mission schedules to take advantage of unexpected science opportunities or unexpected results, and worked with crew members to resolve problems with their experiments. This photo is of Space classroom students in the Discovery Optics Lab at MSFC during STS-35, ASTRO-1 mission payload operations.
SpaceX Falcon Heavy Demo Flight - Ready for Launch
2018-02-06
A SpaceX Falcon Heavy stands at Launch Complex 39A, far right, at NASA's Kennedy Space Center in Florida awaiting liftoff on its demonstration flight. In the foreground is the center’s iconic Vehicle Assembly Building. The demonstration flight is a significant milestone for the world's premier multi-user spaceport. In 2014, NASA signed a property agreement with SpaceX for the use and operation of the center's pad 39A, where the company has launched Falcon 9 rockets and is preparing for the first Falcon Heavy. NASA also has Space Act Agreements in place with partners, such as SpaceX, to provide services needed to process and launch rockets and spacecraft.
Flight Testing the X-36: The Test Pilots Perspective
NASA Technical Reports Server (NTRS)
Walker, Laurence A.
1997-01-01
The X-36 is a 28% scale, remotely piloted research aircraft, designed to demonstrate tailless fighter agility. Powered by a modified Williams International F-112 jet engine, the X-36 uses thrust vectoring and a fly-by-wire control system. Although too small for an onboard pilot, a full-sized remote cockpit was designed to virtually place the test pilot into the aircraft using a variety of innovative techniques. To date, 22 flights have been flown, successfully completing the second phase of testing. Handling qualities have been matching predictions; the test operation is flown similarly to that for full sized manned aircraft. All takeoffs, test maneuvers and landings are flown by the test pilot, affording a greater degree of flexibility and the ability to handle the inevitable unknowns which may occur during highly experimental test programs. The cockpit environment, cues, and display techniques used in this effort have proven to enhance the 'virtual' test pilot's awareness and have helped ensure a successful RPV test program.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Whitten, B.T.; Kesler, J.K.
The report documents the procedures, events, and results of vehicle dynamic tests carried out on the ASEA-Brown Boveri (ABB) X2000 tilt body trainset in the US between October 1992 and January 1993. These tests, sponsored by Amtrak and supported by the FRA, were conducted to assess the suitability of the X2000 trainset for safe operation at elevated cant deficiencies and speeds in Amtrak's Northeast Corridor under existing track conditions in a revenue service demonstration. The report describes the safety criteria against which the performance of the X2000 test train was examined, the instrumentation used, the test locations, and the trackmore » conditions. Preliminary results are presented from tests conducted on Amtrak lines between Philadelphia and Harrisburg, PA, and between Washington DC and New York NY, in which cant deficiencies of 12.5 inches and speeds of 154 mph were reached in a safe and controlled manner. The significance of the results is discussed, and preliminary conclusions and recommendations are presented.« less
64 x 64 thresholding photodetector array for optical pattern recognition
NASA Astrophysics Data System (ADS)
Langenbacher, Harry; Chao, Tien-Hsin; Shaw, Timothy; Yu, Jeffrey W.
1993-10-01
A high performance 32 X 32 peak detector array is introduced. This detector consists of a 32 X 32 array of thresholding photo-transistor cells, manufactured with a standard MOSIS digital 2-micron CMOS process. A built-in thresholding function that is able to perform 1024 thresholding operations in parallel strongly distinguishes this chip from available CCD detectors. This high speed detector offers responses from one to 10 milliseconds that is much higher than the commercially available CCD detectors operating at a TV frame rate. The parallel multiple peaks thresholding detection capability makes it particularly suitable for optical correlator and optoelectronically implemented neural networks. The principle of operation, circuit design and the performance characteristics are described. Experimental demonstration of correlation peak detection is also provided. Recently, we have also designed and built an advanced version of a 64 X 64 thresholding photodetector array chip. Experimental investigation of using this chip for pattern recognition is ongoing.
1990-12-02
The primary objective of the STS-35 mission was round the clock observation of the celestial sphere in ultraviolet and X-Ray astronomy with the Astro-1 observatory which consisted of four telescopes: the Hopkins Ultraviolet Telescope (HUT); the Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE); the Ultraviolet Imaging Telescope (UIT); and the Broad Band X-Ray Telescope (BBXRT). The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Teams of controllers and researchers directed on-orbit science operations, sent commands to the spacecraft, received data from experiments aboard the Space Shuttle, adjusted mission schedules to take advantage of unexpected science opportunities or unexpected results, and worked with crew members to resolve problems with their experiments. Due to loss of data used for pointing and operating the ultraviolet telescopes, MSFC ground teams were forced to aim the telescopes with fine tuning by the flight crew. This photo captures the activity at the Operations Control Facility during the mission as Dr. Urban and Paul Whitehouse give a “thumbs up”.
X-31 quasi-tailless flight demonstration
NASA Technical Reports Server (NTRS)
Huber, Peter; Schellenger, Harvey G.
1994-01-01
The primary objective of the quasi-tailless flight demonstration is to demonstrate the feasibility of using thrust vectoring for directional control of an unstable aircraft. By using this low-cost, low-risk approach it is possible to get information about required thrust vector control power and deflection rates from an inflight experiment as well as insight in low-power thrust vectoring issues. The quasi-tailless flight demonstration series with the X-31 began in March 1994. The demonstration flight condition was Mach 1.2 at 37,500 feet. A series of basic flying quality maneuvers, doublets, bank to bank rolls, and wind-up-turns have been performed with a simulated 100% vertical tail reduction. Flight test and supporting simulation demonstrated that the quasi-tailless approach is effective in representing the reduced stability of tailless configurations. The flights also demonstrated that thrust vectoring could be effectively used to stabilize a directionally unstable configuration and provide control power for maneuver coordination.
The low intensity X-ray imaging scope /Lixiscope/
NASA Technical Reports Server (NTRS)
Yin, L. I.; Trombka, J. I.; Seltzer, S. M.; Webber, R. L.; Farr, M. R.; Rennie, J.
1978-01-01
A fully portable, small-format X-ray imaging system, Lixiscope (low intensity X-ray imaging scope) is described. In the prototype, which has been built to demonstrate the feasibility of the Lixiscope concept, only well-developed and available components have been used. Consideration is given to the principles of operation of the device, some of its performance characteristics as well as possible dental, medical and industrial applications.
NASA's ATM Technology Demonstration-1: Integrated Concept of Arrival Operations
NASA Technical Reports Server (NTRS)
Baxley, Brian T.; Swenson, Harry N.; Prevot, Thomas; Callantine, Todd J.
2012-01-01
This paper describes operations and procedures envisioned for NASA s Air Traffic Management (ATM) Technology Demonstration #1 (ATD-1). The ATD-1 Concept of Operations (ConOps) demonstration will integrate three NASA technologies to achieve high throughput, fuel-efficient arrival operations into busy terminal airspace. They are Traffic Management Advisor with Terminal Metering (TMA-TM) for precise time-based schedules to the runway and points within the terminal area, Controller-Managed Spacing (CMS) decision support tools for terminal controllers to better manage aircraft delay using speed control, and Flight deck Interval Management (FIM) avionics and flight crew procedures to conduct airborne spacing operations. The ATD-1 concept provides de-conflicted and efficient operations of multiple arrival streams of aircraft, passing through multiple merge points, from top-of-descent (TOD) to touchdown. It also enables aircraft to conduct Optimized Profile Descents (OPDs) from en route altitude to the runway, using primarily speed control to maintain separation and schedule. The ATD-1 project is currently addressing the challenges of integrating the three technologies, and implantation into an operational environment. Goals of the ATD-1 demonstration include increasing the throughput of high-density airports, reducing controller workload, increasing efficiency of arrival operations and the frequency of trajectory-based operations, and promoting aircraft ADS-B equipage.
Sex-specific gait adaptations prior to and up to six months after ACL reconstruction
Stasi, Stephanie L. Di; Hartigan, Erin H.; Snyder-Mackler, Lynn
2015-01-01
STUDY DESIGN Controlled longitudinal laboratory study. OBJECTIVES Compare sagittal plane gait mechanics of men and women before and up to 6 months after anterior cruciate ligament reconstruction (ACLR). BACKGROUND Aberrant gait patterns are ubiquitous after anterior cruciate ligament (ACL) rupture and persist after ACLR despite skilled physical therapy. Sex influences post-operative function and second ACL injury risk, but its influence on gait adaptations after injury have not been investigated. METHODS Sagittal plane knee and hip joint excursions during midstance and internal knee and hip extension moments at peak knee flexion were collected on 12 women and 27 men using 3-dimensional gait analysis before (Screen) and after pre-operative physical therapy (Pre-sx), and 6 months after ACLR (6mo). Repeated measures analysis of variance models were used to determine whether limb asymmetries changed differently over time in men and women. RESULTS Significant time x limb x sex interactions were identified for hip and knee excursions and internal knee extension moments (P≤.007). Both sexes demonstrated smaller knee excursions on the involved compared to the uninvolved knee at each time point (P≤.007), but only women demonstrated a decrease in the involved knee excursion from pre-sx to 6mo (P=.03). Women also demonstrated smaller hip excursions (P<.001) and internal knee extension moments (P=.005) on the involved limb compared to the uninvolved limb at 6mo. Men demonstrated smaller hip excursions and knee moments on the involved limb compared to the uninvolved limb (main effects, P<.001). CONCLUSION The persistence of limb asymmetries in men and women 6 months after ACLR indicates that current rehabilitation efforts are inadequate for some individuals following ACLR. PMID:25627155
Field evaluation of a prototype paper-based point-of-care fingerstick transaminase test.
Pollock, Nira R; McGray, Sarah; Colby, Donn J; Noubary, Farzad; Nguyen, Huyen; Nguyen, The Anh; Khormaee, Sariah; Jain, Sidhartha; Hawkins, Kenneth; Kumar, Shailendra; Rolland, Jason P; Beattie, Patrick D; Chau, Nguyen V; Quang, Vo M; Barfield, Cori; Tietje, Kathy; Steele, Matt; Weigl, Bernhard H
2013-01-01
Monitoring for drug-induced liver injury (DILI) via serial transaminase measurements in patients on potentially hepatotoxic medications (e.g., for HIV and tuberculosis) is routine in resource-rich nations, but often unavailable in resource-limited settings. Towards enabling universal access to affordable point-of-care (POC) screening for DILI, we have performed the first field evaluation of a paper-based, microfluidic fingerstick test for rapid, semi-quantitative, visual measurement of blood alanine aminotransferase (ALT). Our objectives were to assess operational feasibility, inter-operator variability, lot variability, device failure rate, and accuracy, to inform device modification for further field testing. The paper-based ALT test was performed at POC on fingerstick samples from 600 outpatients receiving HIV treatment in Vietnam. Results, read independently by two clinic nurses, were compared with gold-standard automated (Roche Cobas) results from venipuncture samples obtained in parallel. Two device lots were used sequentially. We demonstrated high inter-operator agreement, with 96.3% (95% C.I., 94.3-97.7%) agreement in placing visual results into clinically-defined "bins" (<3x, 3-5x, and >5x upper limit of normal), >90% agreement in validity determination, and intraclass correlation coefficient of 0.89 (95% C.I., 0.87-0.91). Lot variability was observed in % invalids due to hemolysis (21.1% for Lot 1, 1.6% for Lot 2) and correlated with lots of incorporated plasma separation membranes. Invalid rates <1% were observed for all other device controls. Overall bin placement accuracy for the two readers was 84% (84.3%/83.6%). Our findings of extremely high inter-operator agreement for visual reading-obtained in a target clinical environment, as performed by local practitioners-indicate that the device operation and reading process is feasible and reproducible. Bin placement accuracy and lot-to-lot variability data identified specific targets for device optimization and material quality control. This is the first field study performed with a patterned paper-based microfluidic device and opens the door to development of similar assays for other important analytes.
X-29 Research Pilot Rogers Smith
NASA Technical Reports Server (NTRS)
1988-01-01
Rogers Smith, a NASA research pilot, is seen here at the cockpit of the X-29 forward-swept-wing technology demonstrator at NASA's Ames-Dryden Flight Research Facility (later the Dryden Flight Research Center), Edwards, California, in 1988. The X-29 explored the use of advanced composites in aircraft construction; variable camber wing surfaces; the unique forward-swept-wing and its thin supercritical airfoil; strake flaps; and a computerized fly-by-wire flight control system that overcame the aircraft's instability. Grumman Aircraft Corporation built two X-29s. They were flight tested at Dryden from 1984 to 1992 in a joint NASA, DARPA (Defense Advanced Research Projects Agency) and U.S. Air Force program. Two X-29 aircraft, featuring one of the most unusual designs in aviation history, flew at the Ames-Dryden Flight Research Facility (now the Dryden Flight Research Center, Edwards, California) from 1984 to 1992. The fighter-sized X-29 technology demonstrators explored several concepts and technologies including: the use of advanced composites in aircraft construction; variable-camber wing surfaces; a unique forward- swept wing and its thin supercritical airfoil; strakes; close-coupled canards; and a computerized fly-by-wire flight control system used to maintain control of the otherwise unstable aircraft. Research results showed that the configuration of forward-swept wings, coupled with movable canards, gave pilots excellent control response at angles of attack of up to 45 degrees. During its flight history, the X-29 aircraft flew 422 research missions and a total of 436 missions. Sixty of the research flights were part of the X-29 follow-on 'vortex control' phase. The forward-swept wing of the X-29 resulted in reverse airflow, toward the fuselage rather than away from it, as occurs on the usual aft-swept wing. Consequently, on the forward-swept wing, the ailerons remained unstalled at high angles of attack. This provided better airflow over the ailerons and prevented stalling (loss of lift) at high angles of attack. Introduction of composite materials in the 1970s opened a new field of aircraft construction. It also made possible the construction of the X-29's thin supercritical wing. State-of-the-art composites allowed aeroelastic tailoring which, in turn, allowed the wing some bending but limited twisting and eliminated structural divergence within the flight envelope (i.e. deformation of the wing or the wing breaking off in flight). Additionally, composite materials allowed the wing to be sufficiently rigid for safe flight without adding an unacceptable weight penalty. The X-29 project consisted of two phases plus the follow-on vortex-control phase. Phase 1 demonstrated that the forward sweep of the X-29 wings kept the wing tips unstalled at the moderate angles of attack flown in that phase (a maximum of 21 degrees). Phase I also demonstrated that the aeroelastic tailored wing prevented structural divergence of the wing within the flight envelope, and that the control laws and control-surface effectiveness were adequate to provide artificial stability for an otherwise unstable aircraft. Phase 1 further demonstrated that the X-29 configuration could fly safely and reliably, even in tight turns. During Phase 2 of the project, the X-29, flying at an angle of attack of up to 67 degrees, demonstrated much better control and maneuvering qualities than computational methods and simulation models had predicted . During 120 research flights in this phase, NASA, Air Force, and Grumman project pilots reported the X-29 aircraft had excellent control response to an angle of attack of 45 degrees and still had limited controllability at a 67-degree angle of attack. This controllability at high angles of attack can be attributed to the aircraft's unique forward-swept wing- canard design. The NASA/Air Force-designed high-gain flight control laws also contributed to the good flying qualities. During the Air Force-initiated vortex-control phase, the X-29 successfully demonstrated vortex flow control (VFC). This VFC was more effective than expected in generating yaw forces, especially in high angles of attack where the rudder is less effective. VFC was less effective in providing control when sideslip (wind pushing on the side of the aircraft) was present, and it did little to decrease rocking oscillation of the aircraft. The X-29 vehicle was a single-engine aircraft, 48.1 feet long with a wing span of 27.2 feet. Each aircraft was powered by a General Electric F404-GE-400 engine producing 16,000 pounds of thrust. The program was a joint effort of the Department of Defense's Defense Advanced Research Projects Agency (DARPA), the U.S. Air Force, the Ames-Dryden Flight Research Facility, the Air Force Flight Test Center, and the Grumman Corporation. The program was managed by the Air Force's Wright Laboratory, Wright Patterson Air Force Base, Ohio.
Lockheed Martin Skunk Works Single Stage to Orbit/Reusable Launch Vehicle
NASA Technical Reports Server (NTRS)
1999-01-01
Lockheed Martin Skunk Works has compiled an Annual Performance Report of the X-33/RLV Program. This report consists of individual reports from all industry team members, as well as NASA team centers. This portion of the report is comprised of a status report of Lockheed Martin's contribution to the program. The following is a summary of the Lockheed Martin Centers involved and work reviewed under their portion of the agreement: (1) Lockheed Martin Skunk Works - Vehicle Development, Operations Development, X-33 and RLV Systems Engineering, Manufacturing, Ground Operations, Reliability, Maintainability/Testability, Supportability, & Special Analysis Team, and X-33 Flight Assurance; (2) Lockheed Martin Technical Operations - Launch Support Systems, Ground Support Equipment, Flight Test Operations, and RLV Operations Development Support; (3) Lockheed Martin Space Operations - TAEM and A/L Guidance and Flight Control Design, Evaluation of Vehicle Configuration, TAEM and A/L Dispersion Analysis, Modeling and Simulations, Frequency Domain Analysis, Verification and Validation Activities, and Ancillary Support; (4) Lockheed Martin Astronautics-Denver - Systems Engineering, X-33 Development; (5) Sanders - A Lockheed Martin Company - Vehicle Health Management Subsystem Progress, GSS Progress; and (6) Lockheed Martin Michoud Space Systems - X-33 Liquid Oxygen (LOX) Tank, Key Challenges, Lessons Learned, X-33/RLV Composite Technology, Reusable Cyrogenic Insulation (RCI) and Vehicle Health Monitoring, Main Propulsion Systems (MPS), Structural Testing, X-33 System Integration and Analysis, and Cyrogenic Systems Operations.
X-24B with Test Pilot Michael V. Love
NASA Technical Reports Server (NTRS)
1973-01-01
This photo shows Air Force Lieutenant Colonel Michael V. Love in front of the X-24B lifting-body research vehicle at Edwards Air Force Base in 1973. Love was assigned as a project pilot on the joint NASA-USAF X-24B Lifting Body flight test program at the NASA Flight Research Center. He made a total of 12 flights in the plane from October 4, 1973 until July 15, 1975. Love flew it to a speed of Mach 1.76 on October 25, 1974, a record for the X-24B. Love attended the USAF Test Pilot School and remained as an instructor there from 1969 through 1971. He was a test pilot at Edwards when assigned to fly to the X-24B. Love was a combat veteran of Vietnam and was awarded the Distinguished Flying Cross with two Oak Leaf clusters. Love perished while attempting an emergency landing in an RF-4C on March 1, 1976. The X-24B was the last aircraft to fly in the Dryden Flight Research Center's manned lifting body program. The X-24 was one of a group of lifting bodies flown by the NASA Flight Research Center (now Dryden Flight Research Center), Edwards, California, in a joint program with the U.S. Air Force at Edwards Air Force Base from 1963 to 1975. The lifting bodies were used to demonstrate the ability of pilots to maneuver and safely land wingless vehicles designed to fly back to Earth from space and be landed like an airplane at a predetermined site. Lifting bodies' aerodynamic lift, essential to flight in the atmosphere, was obtained from their shape. The addition of fins and control surfaces allowed the pilots to stabilize and control the vehicles and regulate their flight paths. Built by Martin Aircraft Company, Maryland, for the U.S. Air Force, the X-24A was a bulbous vehicle shaped like a teardrop with three vertical fins at the rear for directional control. It weighed 6,270 pounds, was 24.5 feet long and 11.5 feet wide (measuring just the fuselage, not the distance between the tips of the outboard fins). Its first unpowered glide flight was on April 17, 1969, with Air Force Maj. Jerauld Gentry at the controls. Gentry also piloted its first powered flight on March 19, 1970. The X-24A was flown 28 times in the program that, like the HL-10, validated the concept that a Space Shuttle vehicle could be landed unpowered. The fastest speed achieved by the X-24A was 1,036 miles per hour (mph--Mach 1.6). Its maximum altitude was 71,400 feet. It was powered by an XLR-11 rocket engine with a maximum theoretical vacuum thrust of 8,480 pounds. The X-24A was later modified into the X-24B. The bulbous shape of the X-24A was converted into a 'flying flatiron' shape with a rounded top, flat bottom, and double delta platform that ended in a pointed nose. The X-24B demonstrated that accurate unpowered reentry vehicle landings were operationally feasible. Top speed achieved by the X-24B was 1,164 mph and the highest altitude it reached was 74,130 feet. The vehicle is on display at the Air Force Museum, Wright-Patterson Air Force Base, Ohio. The pilot on the last powered flight of the X-24B was Bill Dana, who also flew the last X-15 flight about seven years earlier. The X-24A shape was later borrowed for the X-38 Crew Return Vehicle (CRV) technology demonstrator for the International Space Station. The X-24B is on public display at the Air Force Museum, Wright-Patterson AFB, Ohio.
X-24B with Test Pilot Lt. Col. Michael V. Love
NASA Technical Reports Server (NTRS)
1976-01-01
This photo shows Air Force Lieutenant Colonel Michael V. Love in front of the X-24B lifting body research vehicle at Edwards Air Force Base in 1976. Love was assigned as a project pilot on the joint NASA-USAF X-24B Lifting Body flight test program at the NASA Flight Research Center. He made a total of 12 flights in the plane from October 4, 1973 until July 15, 1975. Love flew it to a speed of Mach 1.76 on October 25, 1974, a record for the X-24B. Love attended the USAF Test Pilot School and remained as an instructor there from 1969 through 1971. He was a test pilot at Edwards when assigned to fly to the X-24B. Love was a combat veteran of Vietnam and was awarded the Distinguished Flying Cross with two Oak Leaf clusters. Love perished while attempting an emergency landing in an RF-4C on March 1, 1976 - less than a month after this photo was taken. The X-24B was the last aircraft to fly in the Dryden Flight Research Center's manned lifting body program. The X-24 was one of a group of lifting bodies flown by the NASA Flight Research Center (now Dryden Flight Research Center), Edwards, California, in a joint program with the U.S. Air Force at Edwards Air Force Base from 1963 to 1975. The lifting bodies were used to demonstrate the ability of pilots to maneuver and safely land wingless vehicles designed to fly back to Earth from space and be landed like an airplane at a predetermined site. Lifting bodies' aerodynamic lift, essential to flight in the atmosphere, was obtained from their shape. The addition of fins and control surfaces allowed the pilots to stabilize and control the vehicles and regulate their flight paths. Built by Martin Aircraft Company, Maryland, for the U.S. Air Force, the X-24A was a bulbous vehicle shaped like a teardrop with three vertical fins at the rear for directional control. It weighed 6,270 pounds, was 24.5 feet long and 11.5 feet wide (measuring just the fuselage, not the distance between the tips of the outboard fins). Its first unpowered glide flight was on April 17, 1969, with Air Force Maj. Jerauld Gentry at the controls. Gentry also piloted its first powered flight on March 19, 1970. The X-24A was flown 28 times in the program that, like the HL-10, validated the concept that a Space Shuttle vehicle could be landed unpowered. The fastest speed achieved by the X-24A was 1,036 miles per hour (mph--Mach 1.6). Its maximum altitude was 71,400 feet. It was powered by an XLR-11 rocket engine with a maximum theoretical vacuum thrust of 8,480 pounds. The X-24A was later modified into the X-24B. The bulbous shape of the X-24A was converted into a 'flying flatiron' shape with a rounded top, flat bottom, and double delta platform that ended in a pointed nose. The X-24B demonstrated that accurate unpowered reentry vehicle landings were operationally feasible. Top speed achieved by the X-24B was 1,164 mph and the highest altitude it reached was 74,130 feet. The vehicle is on display at the Air Force Museum, Wright-Patterson Air Force Base, Ohio. The pilot on the last powered flight of the X-24B was Bill Dana, who also flew the last X-15 flight about seven years earlier. The X-24A shape was later borrowed for the X-38 Crew Return Vehicle (CRV) technology demonstrator for the International Space Station. The X-24B is on public display at the Air Force Museum, Wright-Patterson AFB, Ohio.
2000-12-08
The X-40 sub-scale technology demonstrator and its U.S. Army CH-47 Chinook helicopter mothership fly over a dry lakebed runway during a captive-carry test flight from NASA's Dryden Flight Research Center, Edwards, California. The X-40 is attached to a sling which is suspended from the CH-47 by a 110-foot-long cable during the tests, while a small parachute trails behind to provide stability. The captive carry flights are designed to verify the X-40's navigation and control systems, rigging angles for its sling, and stability and control of the helicopter while carrying the X-40 on a tether. Following a series of captive-carry flights, the X-40 made free flights from a launch altitude of about 15,000 feet above ground, gliding to a fully autonomous landing. The X-40 is an unpowered 82 percent scale version of the X-37, a Boeing-developed spaceplane designed to demonstrate various advanced technologies for development of future lower-cost access to space vehicles.
2000-12-08
Ground crewmen help guide the alignment of the X-40 technology demonstrator as the experimental craft is gently lowered to the ground by a U.S. Army CH-47 Chinook cargo helicopter following a captive-carry test flight at NASA's Dryden Flight Research Center, Edwards, California. The X-40 is an unpowered 82 percent scale version of the X-37, a Boeing-developed spaceplane designed to demonstrate various advanced technologies for development of future lower-cost access to space vehicles. The X-37 will be carried into space aboard a space shuttle and then released to perform various maneuvers and a controlled re-entry through the Earth's atmosphere to an airplane-style landing on a runway, controlled entirely by pre-programmed computer software. Following a series of captive-carry flights, the X-40 made several free flights from a launch altitude of about 15,000 feet above ground, gliding to a fully autonomous landing. The captive carry flights helped verify the X-40's navigation and control systems, rigging angles for its sling, and stability and control of the helicopter while carrying the X-40 on a tether.
40 CFR 63.4951 - How do I demonstrate initial compliance with the emission limitations?
Code of Federal Regulations, 2010 CFR
2010-07-01
... without add-on controls option for any individual coating operation, for any group of coating operations in the affected source, or for all the coating operations in the affected source to demonstrate... emission rate with add-on controls option for any coating operation in the affected source for which you do...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Xu, Tengfang
2006-10-20
Lawrence Berkeley National Laboratory (LBNL) is now finalizing the Phase 2 Research and Demonstration Project on characterizing 2-foot x 4-foot (61-cm x 122-cm) fan-filter units in the market using the first-ever standard laboratory test method developed at LBNL.[1][2][3] Fan-filter units deliver re-circulated air and provide particle filtration control for clean environments. Much of the energy in cleanrooms (and minienvironments) is consumed by 2-foot x 4-foot (61-cm x 122-cm) or 4-foot x 4-foot (122-cm x 122-cm) fan-filter units that are typically located in the ceiling (25-100% coverage) of cleanroom controlled environments. Thanks to funding support by the California Energy Commission's Industrialmore » Program of the Public Interest Energy Research (PIER) Program, and significant participation from manufacturers and users of fan-filter units from around the world, LBNL has developed and performed a series of standard laboratory tests and reporting on a variety of 2-foot x 4-foot (61-cm x 122-cm) fan-filter units (FFUs). Standard laboratory testing reports have been completed and reported back to anonymous individual participants in this project. To date, such reports on standard testing of FFU performance have provided rigorous and useful data for suppliers and end users to better understand, and more importantly, to quantitatively characterize performance of FFU products under a variety of operating conditions.[1] In the course of the project, the standard laboratory method previously developed at LBNL has been under continuous evaluation and update.[2][3] Based upon the updated standard, it becomes feasible for users and suppliers to characterize and evaluate energy performance of FFUs in a consistent way.« less
SpaceX Recovery Trainer Egress and Handling Testing
2018-04-17
Pararescue specialists from the 304th Rescue Squadron, located in Portland, Oregon and supporting the 45th Operations Group’s Detachment 3, based out of Patrick Air Force Base, prepare equipment during an April astronaut rescue exercise with NASA’s Commercial Crew Program and SpaceX off of Florida’s eastern coast. The pararescue specialists, also known as “Guardian Angels,” jumped from military aircraft and simulated a rescue operation to demonstrate their ability to safely remove crew from the SpaceX Crew Dragon in the unlikely event of an emergency landing. The pararescue specialists are fully qualified paramedics able to perform field surgery, if necessary.
Control of a multidegree of freedom standing wave ultrasonic motor driven precise positioning system
NASA Astrophysics Data System (ADS)
Ferreira, Antoine; Minotti, Patrice
1997-04-01
A newly developed positioning system incorporating a multidegree of freedom standing wave ultrasonic motor (SWUM) is presented and its advantageous features, operating principles, and some experimental results are described. The principle of motorization is based on the conversion, through frictional contact, of a stationary bending vibration sustained in a slotted metallic resonator, into rigid body displacements. A small autonomous multidegree of freedom nanopositioner using a SWUM motor is presented for fine positioning in scanning tunneling microscopy. The positioning system is achieved via the simultaneous operation of two identical pulse width modulation servo-control systems, each having a laser vibrometer position feedback loop. The closed loop position schemes are theoretically considered and their results are demonstrated and evaluated in practice. Evaluations of experimental tests indicate that a positioning resolution less than 100 nm are successfully achieved for an unlimited X-Y travel range with linear speeds between 1 mm s-1 and few cm s-1.
Using Neural Networks in Decision Making for a Reconfigurable Electro Mechanical Actuator (EMA)
NASA Technical Reports Server (NTRS)
Latino, Carl D.
2001-01-01
The objectives of this project were to demonstrate applicability and advantages of a neural network approach for evaluating the performance of an electro-mechanical actuator (EMA). The EMA in question was intended for the X-37 Advanced Technology Vehicle. It will have redundant components for safety and reliability. The neural networks for this application are to monitor the operation of the redundant electronics that control the actuator in real time and decide on the operating configuration. The system we proposed consists of the actuator, sensors, control circuitry and dedicated (embedded) processors. The main purpose of the study was to develop suitable hardware and neural network capable of allowing real time reconfiguration decisions to be made. This approach was to be compared to other methods such as fuzzy logic and knowledge based systems considered for the same application. Over the course of the project a more general objective was the identification of the other neural network applications and the education of interested NASA personnel on the topic of Neural Networks.
A vacuum-sealed miniature X-ray tube based on carbon nanotube field emitters
NASA Astrophysics Data System (ADS)
Heo, Sung Hwan; Kim, Hyun Jin; Ha, Jun Mok; Cho, Sung Oh
2012-05-01
A vacuum-sealed miniature X-ray tube based on a carbon nanotube field-emission electron source has been demonstrated. The diameter of the X-ray tube is 10 mm; the total length of the tube is 50 mm, and no external vacuum pump is required for the operation. The maximum tube voltage reaches up to 70 kV, and the X-ray tube generates intense X-rays with the air kerma strength of 108 Gy·cm2 min-1. In addition, X-rays produced from the miniature X-ray tube have a comparatively uniform spatial dose distribution.
User Friendly Real Time Display
NASA Astrophysics Data System (ADS)
McCarthy, Denise M.; McCracken, Bill
1989-02-01
Real-time viewing of high resolution infrared line scan reconnaissance imagery is greatly facilitated using Honeywell's Real Time Display in conjunction with a D-500 Infrared Reconnaissance System. The Real-Time Display (RTD) provides the capability of on-board review of high resolution infrared imagery using the wide infrared dynamic range of the D-500 infrared receiver to maximum advantage. The scan converter accepts, processes, and displays imagery from four channels of the IR Receiver after formatting by a multiplexer. The scan converter interfaces with a standard RS-170 video monitor. Detailed review and on-board analysis of infrared reconnaissance imagery stored on a videotape is easily accomplished using the many user-friendly features of the RTD. Using a convenient joystick controller, on-screen mode menus, and a moveable cursor, the operator can examine scenes of interest at four different display magnifications using a four step bidirectional zoom. Imagery areas of interest are first noted using the scrolling wide field display mode at 8x reduced display resolution. On noting an area of interest, the imagery can be marked on the tape record for future recovery and a freeze frame mode can be initiated. The operator can then move the cursor to the area of interest and zoom to higher display magnification for 4x, 2x, and lx display resolutions so that the full 4096 x 4096 pixel infrared frame can be matched to the 512 x 512 pixel display frame. At 8x wide field display magnification the full line scanner field of view is displayed at 8x reduced resolution. There are two selectable modes of obtaining this reduced resolution. The operator can use the default method, which averages the signal from an 8 x 8 pixel group, or it is also possible to select the peak signal of the 8 x 8 pixel block to represent the entire block on the display. In this alternate peak-signal display the wide field can be effectively scanned for hot objects which are more likely to be candidate targets. The intermediate 4x and 2x zoom steps are very useful in maintaining operator orientation in examining target clusters and industrial complexes. The four operating modes of the RTD are described and their use to the operator on a typical mission is outlined. Some installation details are given. The RTD as part of a complete D-500 Infrared Linescan Reconnaissance System is now being installed on a Beech 1900 Environmental Control Aircraft to monitor pollution in very sensitive and commercially important marine ecologies. Its application on military reconnaissance missions will allow the normal review of recorded videotape imagery at a ground station immediately after return of the aircraft to base. The areas of highest interest will have been previously marked during the airborne real-time review by the operator. The RTD packages into only two Line Replaceable Units (LRUs), a Scan Converter, and a Control Unit which includes a joystick hand controller. The CRT display is assumed to be part of the aircraft.
NASA Astrophysics Data System (ADS)
Keefe, Laurence
2016-11-01
Parabolized acoustic propagation in transversely inhomogeneous media is described by the operator update equation U (x , y , z + Δz) =eik0 (- 1 +√{ 1 + Z }) U (x , y , z) for evolution of the envelope of a wavetrain solution to the original Helmholtz equation. Here the operator, Z =∇T2 + (n2 - 1) , involves the transverse Laplacian and the refractive index distribution. Standard expansion techniques (on the assumption Z << 1)) produce pdes that approximate, to greater or lesser extent, the full dispersion relation of the original Helmholtz equation, except that none of them describe evanescent/damped waves without special modifications to the expansion coefficients. Alternatively, a discretization of both the envelope and the operator converts the operator update equation into a matrix multiply, and existing theorems on matrix functions demonstrate that the complete (discrete) Helmholtz dispersion relation, including evanescent/damped waves, is preserved by this discretization. Propagation-constant/damping-rates contour comparisons for the operator equation and various approximations demonstrate this point, and how poorly the lowest-order, textbook, parabolized equation describes propagation in lined ducts.
Thermal Management Design for the X-33 Lifting Body
NASA Technical Reports Server (NTRS)
Bouslog, S.; Mammano, J.; Strauss, B.
1998-01-01
The X-33 Advantage Technology Demonstrator offers a rare and exciting opportunity in Thermal Protection System development. The experimental program incorporates the latest design innovation in re-useable, low life cycle cost, and highly dependable Thermal Protection materials and constructions into both ground based and flight test vehicle validations. The unique attributes of the X-33 demonstrator for design application validation for the full scale Reusable Launch Vehicle, (RLV), are represented by both the configuration of the stand-off aeroshell, and the extreme exposures of sub-orbital hypersonic re-entry simulation. There are several challenges of producing a sub-orbital prototype demonstrator of Single Stage to Orbit/Reusable Launch Vehicle (SSTO/RLV) operations. An aggressive schedule with budgetary constraints precludes the opportunity for an extensive verification and qualification program of vehicle flight hardware. However, taking advantage of off the shelf components with proven technologies reduces some of the requirements for additional testing. The effects of scale on thermal heating rates must also be taken into account during trajectory design and analysis. Described in this document are the unique Thermal Protection System (TPS) design opportunities that are available with the lifting body configuration of the X-33. The two principal objectives for the TPS are to shield the primary airframe structure from excessive thermal loads and to provide an aerodynamic mold line surface. With the relatively benign aeroheating capability of the lifting body, an integrated stand-off aeroshell design with minimal weight and reduced procurement and operational costs is allowed. This paper summarizes the design objectives of the X-33 TPS, the flight test requirements driven configuration, and design benefits. Comparisons are made of the X-33 flight profiles and Space Shuttle Orbiter, and lifting body Reusable Launch Vehicle aerothermal environments. The X-33 TPS is based on a design to cost configuration concept. Only RLV critical technologies are verified to conform to cost and schedule restrictions. The one-off prototype vehicle configuration has evolved to minimize the tooling costs by reducing the number of unique components. Low cost approaches such as a composite/blanket leeward aeroshell and the use of Shuttle technology are implemented where applicable. The success of the X-33 will overcome the ballistic re-entry TPS mindset. The X-33 TPS is tailored to an aircraft type mission while maintaining sufficient operational margins. The flight test program for the X-33 will demonstrate that TPS for the RLV is not simply a surface insulation but rather an integrated aeroshell system.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hinton, W.S.; Maxwell, J.D.; Healy, E.C.
1997-12-31
This paper describes the completed Innovative Clean Coal Technology project which demonstrated SCR technology for reduction of flue gas NO{sub x} emissions from a utility boiler burning US high-sulfur coal. The project was sponsored by the US Department of Energy, managed and co-funded by Southern Company Services, Inc. on behalf of the Southern Company, and also co-funded by the Electric Power Research Institute and Ontario Hydro. The project was located at Gulf Power Company`s Plant Crist Unit 5 (a 75 MW tangentially-fired boiler burning US coals that had a sulfur content ranging from 2.5--2.9%), near Pensacola, Florida. The test programmore » was conducted for approximately two years to evaluate catalyst deactivation and other SCR operational effects. The SCR test facility had nine reactors: three 2.5 MW (5,000 scfm), and operated on low-dust flue gas. The reactors operated in parallel with commercially available SCR catalysts obtained from suppliers throughout the world. Long-term performance testing began in July 1993 and was completed in July 1995. A brief test facility description and the results of the project are presented in this paper.« less
2018-02-28
On February 28, SpaceX completed a demonstration of their ability to recover the crew and capsule after a nominal water splashdown. This marks an important recovery milestone and joint test. The timeline requirement from splashdown to crew egress onboard the ship is one hour, and the recovery team demonstrated that they can accomplish this operation under worst-case conditions in under 45 minutes. Further improvements are planned to shorten the recovery time even more as the team works to build a process that is safe, repeatable, and efficient.
NASA Astrophysics Data System (ADS)
Mu, Xiaodong; Crain, William; Nguyen, Can; Ionov, Pavel; Steinvurzel, Paul; Dotan, Yaniv; Karuza, Petras; Lotshaw, William; Rose, Todd; Beck, Steven; Anderson, F. Scott
2018-02-01
A 1064 nm, 1 mJ pulsed fiber MOPA module, housed in 16"x14"x2.5" package for application in a lunar and planetary in-situ surface dating instrument is demonstrated. The module is based on a three-stage MOPA with a 60 μm core tapered fiber terminal amplifier. The master oscillator and first two preamplifier stages, which generate 20 μJ pulses, are all contained on a 13"x11"x1" board. Several improvements to the electronic signal control were instrumental to the laser development, including bipolar drive of the phase modulator for SBS suppression, shaping of the seed pulse to compensate pulse steepening, and pulsed operation of the power amplifier pump to reduce spontaneous emission at low pulse repetition frequency. The packaged laser runs at a repetition rate of 10 kHz and generates 10 ns pulses at 1 mJ with a 40 GHz linewidth, an M2 1.2 beam quality, and an 18 dB polarization extinction ratio. The modular design enables seven independent lasers to be stacked in a 20"x18"x16.25" enclosure, supporting a path towards a fiber laser based LARIMS for advanced materials characterization and chronological dating in harsh and remote environments.
Robust Modal Filtering and Control of the X-56A Model with Simulated Fiber Optic Sensor Failures
NASA Technical Reports Server (NTRS)
Suh, Peter M.; Chin, Alexander W.; Marvis, Dimitri N.
2014-01-01
The X-56A aircraft is a remotely-piloted aircraft with flutter modes intentionally designed into the flight envelope. The X-56A program must demonstrate flight control while suppressing all unstable modes. A previous X-56A model study demonstrated a distributed-sensing-based active shape and active flutter suppression controller. The controller relies on an estimator which is sensitive to bias. This estimator is improved herein, and a real-time robust estimator is derived and demonstrated on 1530 fiber optic sensors. It is shown in simulation that the estimator can simultaneously reject 230 worst-case fiber optic sensor failures automatically. These sensor failures include locations with high leverage (or importance). To reduce the impact of leverage outliers, concentration based on a Mahalanobis trim criterion is introduced. A redescending M-estimator with Tukey bisquare weights is used to improve location and dispersion estimates within each concentration step in the presence of asymmetry (or leverage). A dynamic simulation is used to compare the concentrated robust estimator to a state-of-the-art real-time robust multivariate estimator. The estimators support a previously-derived mu-optimal shape controller. It is found that during the failure scenario, the concentrated modal estimator keeps the system stable.
Robust Modal Filtering and Control of the X-56A Model with Simulated Fiber Optic Sensor Failures
NASA Technical Reports Server (NTRS)
Suh, Peter M.; Chin, Alexander W.; Mavris, Dimitri N.
2016-01-01
The X-56A aircraft is a remotely-piloted aircraft with flutter modes intentionally designed into the flight envelope. The X-56A program must demonstrate flight control while suppressing all unstable modes. A previous X-56A model study demonstrated a distributed-sensing-based active shape and active flutter suppression controller. The controller relies on an estimator which is sensitive to bias. This estimator is improved herein, and a real-time robust estimator is derived and demonstrated on 1530 fiber optic sensors. It is shown in simulation that the estimator can simultaneously reject 230 worst-case fiber optic sensor failures automatically. These sensor failures include locations with high leverage (or importance). To reduce the impact of leverage outliers, concentration based on a Mahalanobis trim criterion is introduced. A redescending M-estimator with Tukey bisquare weights is used to improve location and dispersion estimates within each concentration step in the presence of asymmetry (or leverage). A dynamic simulation is used to compare the concentrated robust estimator to a state-of-the-art real-time robust multivariate estimator. The estimators support a previously-derived mu-optimal shape controller. It is found that during the failure scenario, the concentrated modal estimator keeps the system stable.
NASA Technical Reports Server (NTRS)
Roberts, Floyd E., III
1994-01-01
Software provides for control and acquisition of data from optical pyrometer. There are six individual programs in PYROLASER package. Provides quick and easy way to set up, control, and program standard Pyrolaser. Temperature and emisivity measurements either collected as if Pyrolaser in manual operating mode or displayed on real-time strip charts and stored in standard spreadsheet format for posttest analysis. Shell supplied to allow macros, which are test-specific, added to system easily. Written using Labview software for use on Macintosh-series computers running System 6.0.3 or later, Sun Sparc-series computers running Open-Windows 3.0 or MIT's X Window System (X11R4 or X11R5), and IBM PC or compatible computers running Microsoft Windows 3.1 or later.
1999-08-23
Construction is under way for the X-33/X-34 hangar complex near the Shuttle Landing Facility at KSC. The Reusable Launch Vehicle (RLV) complex will include facilities for related ground support equipment and administrative/ technical support. It will be available to accommodate the Space Shuttle; the X-34 RLV technology demonstrator; the L-1011 carrier aircraft for Pegasus and X-34; and other RLV and X-vehicle programs. The complex is jointly funded by the Spaceport Florida Authority, NASA's Space Shuttle Program and KSC. The facility will be operational in early 2000
2004-04-15
This is an artist's concept of the completely operational International Space Station being approached by an X-33 Reusable Launch Vehicle (RLV). The X-33 program was designed to pave the way to a full-scale, commercially developed RLV as the flagship technology demonstrator for technologies that would lower the cost of access to space. It is unpiloted, taking off vertically like a rocket, reaching an altitude of up to 60 miles and speeds between Mach 13 and 15, and landing horizontally like an airplane. The X-33 program was cancelled in 2001.
A hard X-ray nanoprobe beamline for nanoscale microscopy.
Winarski, Robert P; Holt, Martin V; Rose, Volker; Fuesz, Peter; Carbaugh, Dean; Benson, Christa; Shu, Deming; Kline, David; Stephenson, G Brian; McNulty, Ian; Maser, Jörg
2012-11-01
The Hard X-ray Nanoprobe Beamline (or Nanoprobe Beamline) is an X-ray microscopy facility incorporating diffraction, fluorescence and full-field imaging capabilities designed and operated by the Center for Nanoscale Materials and the Advanced Photon Source at Sector 26 of the Advanced Photon Source at Argonne National Laboratory. This facility was constructed to probe the nanoscale structure of biological, environmental and material sciences samples. The beamline provides intense focused X-rays to the Hard X-ray Nanoprobe (or Nanoprobe) which incorporates Fresnel zone plate optics and a precision laser sensing and control system. The beamline operates over X-ray energies from 3 to 30 keV, enabling studies of most elements in the periodic table, with a particular emphasis on imaging transition metals.
Best, Stephen P; Levina, Aviva; Glover, Chris; Johannessen, Bernt; Kappen, Peter; Lay, Peter A
2016-05-01
The design and operation of a low-volume spectroelectrochemical cell for X-ray absorption spectroscopy (XAS) of solutions at room temperature is described. Fluorescence XAS measurements are obtained from samples contained in the void space of a 50 µL reticulated vitreous carbon (sponge) working electrode. Both rapid electrosynthesis and control of the effects of photoreduction are achieved by control over the flow properties of the solution through the working electrode, where a good balance between the rate of consumption of sample and the minimization of decomposition was obtained by pulsing the flow of the solution by 1-2 µL with duty cycle of ∼3 s while maintaining a small net flow rate (26-100 µL h(-1)). The performance of the cell in terms of control of the redox state of the sample and minimization of the effects of photoreduction was demonstrated by XAS measurements of aqueous solutions of the photosensitive Fe(III) species, [Fe(C2O4)3](3-), together with that of the electrogenerated [Fe(C2O4)3](4-) product. The current response from the cell during the collection of XAS spectra provides an independent measure of the stability of the sample of the measurement. The suitability of the approach for the study of small volumes of mM concentrations of protein samples was demonstrated by the measurement of the oxidized and electrochemically reduced forms of cytochrome c.
DOT National Transportation Integrated Search
2008-12-01
Programmable logic controllers (PLCs) were installed at several key ramps with the assistance of the City of Portland and used to capture additional data about ramp operations that are not otherwise logged. The data include include the activation and...
Enhanced networks operations using the X Window System
NASA Technical Reports Server (NTRS)
Linares, Irving
1993-01-01
We propose an X Window Graphical User Interface (GUI) which is tailored to the operations of NASA GSFC's Network Control Center (NCC), the NASA Ground Terminal (NGT), the White Sands Ground Terminal (WSGT), and the Second Tracking and Data Relay Satellite System (TDRSS) Ground Terminal (STGT). The proposed GUI can also be easily extended to other Ground Network (GN) Tracking Stations due to its standardized nature.
Host-Nation Operations: Soldier Training on Governance (HOST-G) Training Support Package
2011-07-01
restricted this webpage from running scripts or ActiveX controls that could access your computer. Click here for options…” • If this occurs, select that...scripts and ActiveX controls can be useful, but active content might also harm your computer. Are you sure you want to let this file run active
Dietrich, Markus; Hagen, Gunter; Reitmeier, Willibald; Burger, Katharina; Hien, Markus; Grass, Philippe; Kubinski, David; Visser, Jaco; Moos, Ralf
2017-11-28
Current developments in exhaust gas aftertreatment led to a huge mistrust in diesel driven passenger cars due to their NO x emissions being too high. The selective catalytic reduction (SCR) with ammonia (NH₃) as reducing agent is the only approach today with the capability to meet upcoming emission limits. Therefore, the radio-frequency-based (RF) catalyst state determination to monitor the NH₃ loading on SCR catalysts has a huge potential in emission reduction. Recent work on this topic proved the basic capability of this technique under realistic conditions on an engine test bench. In these studies, an RF system calibration for the serial type SCR catalyst Cu-SSZ-13 was developed and different approaches for a temperature dependent NH₃ storage were determined. This paper continues this work and uses a fully calibrated RF-SCR system under transient conditions to compare different directly measured and controlled NH₃ storage levels, and NH₃ target curves. It could be clearly demonstrated that the right NH₃ target curve, together with a direct control on the desired level by the RF system, is able to operate the SCR system with the maximum possible NO x conversion efficiency and without NH₃ slip.
NASA Astrophysics Data System (ADS)
Moralis-Pegios, M.; Terzenidis, N.; Vagionas, C.; Pitris, S.; Chatzianagnostou, E.; Brimont, A.; Zanzi, A.; Sanchis, P.; Marti, J.; Kraft, J.; Rochracher, K.; Dorrestein, S.; Bogdan, M.; Tekin, T.; Syrivelis, D.; Tassiulas, L.; Miliou, A.; Pleros, N.; Vyrsokinos, K.
2017-02-01
Programmable switching nodes supporting Software-Defined Networking (SDN) over optical interconnecting technologies arise as a key enabling technology for future disaggregated Data Center (DC) environments. The SDNenabling roadmap of intra-DC optical solutions is already a reality for rack-to-rack interconnects, with recent research reporting on interesting applications of programmable silicon photonic switching fabrics addressing board-to-board and even on-board applications. In this perspective, simplified information addressing schemes like Bloom filter (BF)-based labels emerge as a highly promising solution for ensuring rapid switch reconfiguration, following quickly the changes enforced in network size, network topology or even in content location. The benefits of BF-based forwarding have been so far successfully demonstrated in the Information-Centric Network (ICN) paradigm, while theoretical studies have also revealed the energy consumption and speed advantages when applied in DCs. In this paper we present for the first time a programmable 4x4 Silicon Photonic switch that supports SDN through the use of BF-labeled router ports. Our scheme significantly simplifies packet forwarding as it negates the need for large forwarding tables, allowing for its remote control through modifications in the assigned BF labels. We demonstrate 1x4 switch operation controlling the Si-Pho switch by a Stratix V FPGA module, which is responsible for processing the packet ID and correlating its destination with the appropriate BF-labeled outgoing port. DAC- and amplifier-less control of the carrier-injection Si-Pho switches is demonstrated, revealing successful switching of 10Gb/s data packets with BF-based forwarding information changes taking place at a time-scale that equals the duration of four consecutive packets.
NASA integrated vehicle health management technology experiment for X-37
NASA Astrophysics Data System (ADS)
Schwabacher, Mark; Samuels, Jeff; Brownston, Lee
2002-07-01
The NASA Integrated Vehicle Health Management (IVHM) Technology Experiment for X-37 was intended to run IVHM software on board the X-37 spacecraft. The X-37 is an unpiloted vehicle designed to orbit the Earth for up to 21 days before landing on a runway. The objectives of the experiment were to demonstrate the benefits of in-flight IVHM to the operation of a Reusable Launch Vehicle, to advance the Technology Readiness Level of this IVHM technology within a flight environment, and to demonstrate that the IVHM software could operate on the Vehicle Management Computer. The scope of the experiment was to perform real-time fault detection and isolation for X-37's electrical power system and electro-mechanical actuators. The experiment used Livingstone, a software system that performs diagnosis using a qualitative, model-based reasoning approach that searches system-wide interactions to detect and isolate failures. Two of the challenges we faced were to make this research software more efficient so that it would fit within the limited computational resources that were available to us on the X-37 spacecraft, and to modify it so that it satisfied the X-37's software safety requirements. Although the experiment is currently unfunded, the development effort resulted in major improvements in Livingstone's efficiency and safety. This paper reviews some of the details of the modeling and integration efforts, and some of the lessons that were learned.
Moftakhar, Parham; Lillaney, Prasheel; Losey, Aaron D; Cooke, Daniel L; Martin, Alastair J; Thorne, Bradford R H; Arenson, Ronald L; Saeed, Maythem; Wilson, Mark W; Hetts, Steven W
2015-12-01
To assess the feasibility of multiplanar vascular navigation with a new magnetically assisted remote-controlled (MARC) catheter with real-time magnetic resonance (MR) imaging at 1.5 T and 3 T and to compare it with standard x-ray guidance in simulated endovascular catheterization procedures. A 1.6-mm-diameter custom clinical-grade microcatheter prototype with lithographed double-saddle coils at the distal tip was deflected with real-time MR imaging. Two inexperienced operators and two experienced operators catheterized anteroposterior (celiac, superior mesenteric, and inferior mesenteric arteries) and mediolateral (renal arteries) branch vessels in a cryogel abdominal aortic phantom. This was repeated with conventional x-ray fluoroscopy by using clinical catheters and guidewires. Mean procedure times and percentage success data were analyzed with linear mixed-effects regression. The MARC catheter tip was visible at 1.5 T and 3 T. Among inexperienced operators, MARC MR imaging guidance was not statistically different from x-ray guidance at 1.5 T (67% successful vessel selection turns with MR imaging vs 76% with x-ray guidance, P = .157) and at 3 T (75% successful turns with MR imaging vs 76% with x-ray guidance, P = .869). Experienced operators were more successful in catheterizing vessels with x-ray guidance (98% success within 60 seconds) than with 1.5-T (65%, P < .001) or 3-T (75%) MR imaging. Among inexperienced operators, mean procedure time was nearly equivalent by using MR imaging (31 seconds) and x-ray guidance (34 seconds, P = .436). Among experienced operators, catheterization was faster with x-ray guidance (20 seconds) compared with 1.5-T MR imaging (42 seconds, P < .001), but MARC guidance improved at 3 T (31 seconds). MARC MR imaging guidance at 3 T was not significantly different from x-ray guidance for the celiac (P = .755), superior mesenteric (P = .358), and inferior mesenteric (P = .065) arteries. Multiplanar navigation with a new MARC catheter with real-time MR imaging at 1.5 T and 3 T is feasible and comparable to x-ray guidance for anteroposterior vessels at 3 T in a vascular phantom.
Moftakhar, Parham; Lillaney, Prasheel; Losey, Aaron D.; Cooke, Daniel L.; Martin, Alastair J.; Thorne, Bradford R. H.; Arenson, Ronald L.; Saeed, Maythem; Wilson, Mark W.
2015-01-01
Purpose To assess the feasibility of multiplanar vascular navigation with a new magnetically assisted remote-controlled (MARC) catheter with real-time magnetic resonance (MR) imaging at 1.5 T and 3 T and to compare it with standard x-ray guidance in simulated endovascular catheterization procedures. Materials and Methods A 1.6-mm–diameter custom clinical-grade microcatheter prototype with lithographed double-saddle coils at the distal tip was deflected with real-time MR imaging. Two inexperienced operators and two experienced operators catheterized anteroposterior (celiac, superior mesenteric, and inferior mesenteric arteries) and mediolateral (renal arteries) branch vessels in a cryogel abdominal aortic phantom. This was repeated with conventional x-ray fluoroscopy by using clinical catheters and guidewires. Mean procedure times and percentage success data were analyzed with linear mixed-effects regression. Results The MARC catheter tip was visible at 1.5 T and 3 T. Among inexperienced operators, MARC MR imaging guidance was not statistically different from x-ray guidance at 1.5 T (67% successful vessel selection turns with MR imaging vs 76% with x-ray guidance, P = .157) and at 3 T (75% successful turns with MR imaging vs 76% with x-ray guidance, P = .869). Experienced operators were more successful in catheterizing vessels with x-ray guidance (98% success within 60 seconds) than with 1.5-T (65%, P < .001) or 3-T (75%) MR imaging. Among inexperienced operators, mean procedure time was nearly equivalent by using MR imaging (31 seconds) and x-ray guidance (34 seconds, P = .436). Among experienced operators, catheterization was faster with x-ray guidance (20 seconds) compared with 1.5-T MR imaging (42 seconds, P < .001), but MARC guidance improved at 3 T (31 seconds). MARC MR imaging guidance at 3 T was not significantly different from x-ray guidance for the celiac (P = .755), superior mesenteric (P = .358), and inferior mesenteric (P = .065) arteries. Conclusion Multiplanar navigation with a new MARC catheter with real-time MR imaging at 1.5 T and 3 T is feasible and comparable to x-ray guidance for anteroposterior vessels at 3 T in a vascular phantom. © RSNA, 2015 Online supplemental material is available for this article. PMID:26030659
Dielectric loaded surface plasmon waveguides for datacom applications
NASA Astrophysics Data System (ADS)
Weeber, J.-C.; Hassan, K.; Nielsen, M. G.; Pitilakis, A.; Tsilipakos, O.; Kriezis, E. E.; Fatome, J.; Finot, C.; Markey, L.; Albrektsen, O.; Bozhevolnyi, S. I.; Dereux, A.
2012-04-01
We rst report on design, fabrication and characterizations of thermally-controlled plasmonic routers relying on the interference of a plasmonic and a photonic mode supported by wide enough dielectric loaded waveguides. We show that, by owing a current through the gold lm on which the dielectric waveguides are deposited, the length of the beating created by the interference of the two modes can be controlled accurately. By operating such a plasmonic dual-mode interferometer switch, symmetric extinction ratio of 7dB are obtained at the output ports of a 2x2 router. Next, we demonstrate ber-to-ber characterizations of stand-alone dielectric loaded surface plasmon waveguide (DLSPPW) devices by using grating couplers. The couplers are comprised of dielectric loaded gratings with carefully chosen periods and duty-cycles close to 0.5. We show that insertion loss below 10dB per coupler can be achieved with optimized gratings. This coupling scheme is used to operate Bit-Error-Rate (BER) measurements for the transmission of a 10Gbits/s signal along a stand-alone straight DLSPPW. We show in particular that these waveguides introduce a rather small BER power penalty (below 1dB) demonstrating the suitability of this plasmonic waveguiding platform for high-bit rate transmission.
X-Ray Testing Constellation-X Optics at MSFC's 100-m Facility
NASA Technical Reports Server (NTRS)
O'Dell, Stephen; Baker, Markus; Content, David; Freeman, Mark; Glenn, Paul; Gubarev, Mikhail; Hair, Jason; Jones, William; Joy, Marshall
2003-01-01
In addition to the 530-m-long X-Ray Calibration Facility (XRCF), NASA's Marshall Space Flight Center (MSFC) operates a 104-m-long (source-to-detector) X-ray-test facility. Originally developed and still occasionally used for stray-light testing of visible-fight optical systems, the so-called "Stray-Light Facility" now serves primarily as a convenient and inexpensive facility for performance evaluation and calibration of X-ray optics and detectors. The facility can accommodate X-ray optics up to about 1-m diameter and 12-m focal length. Currently available electron-impact sources at the facility span the approximate energy range 0.2 to 100 keV, thus supporting testing of soft- and hard-X-ray optics and detectors. Available MSFC detectors are a front-illuminated CCD (charge-coupled device) and a scanning CZT (cadmium--zinc--telluride) detector, with low-energy cut-offs of about 0.8 and 3 keV, respectively. In order to test developmental optics for the Constellation-X Project, led by NASA's Goddard Space Flight Center (GSFC), MSFC undertook several enhancements to the facility. Foremost among these was development and fabrication of a five-degree-of-freedom (5-DoF) optics mount and control system, which translates and tilts the user-provided mirror assembly suspended from its interface plate. Initial Constellation-X tests characterize the performance of the Optical Alignment Pathfinder Two (OAP2) for the large Spectroscopy X-ray Telescope (SXT) and of demonstration mirror assemblies for the Hard X-ray Telescope (HXT). With the Centroid Detector Assembly (CDA), used for precision alignment of the Chandra (nee AXAF) mirrors, the Constellation-X SXT Team optically aligned the individual mirrors of the OAPZ at GSFC. The team then developed set-up and alignment procedures, including transfer of the alignment from the optical alignment facility at GSFC to the X-ray test facility at MSFC, using a reference flat and fiducials. The OAPZ incorporates additional ancillary features --- fixed aperture mask and movable sub-aperture mask --- to facilitate X-ray characterization of the optics. Although the OAPZ was designed to- have low sensitivity to temperature offsets and gradients, analyses showed the necessity of active temperature control for the X-ray performance testing. Thus, the Smithsonian Astrophysical Observatory (SAO) implemented a thermal control and monitoring system, designed to hold the OAP2 close to its assembly.
Integrated Ground Operations Demonstration Units Testing Plans and Status
NASA Technical Reports Server (NTRS)
Johnson, Robert G.; Notardonato, William U.; Currin, Kelly M.; Orozco-Smith, Evelyn M.
2012-01-01
Cryogenic propellant loading operations with their associated flight and ground systems are some of the most complex, critical activities in launch operations. Consequently, these systems and operations account for a sizeable portion of the life cycle costs of any launch program. NASA operations for handling cryogens in ground support equipment have not changed substantially in 50 years, despite advances in cryogenics, system health management and command and control technologies. This project was developed to mature, integrate and demonstrate advancement in the current state of the art in these areas using two distinct integrated ground operations demonstration units (GODU): GODU Integrated Refrigeration and Storage (IRAS) and GODU Autonomous Control
A CMOS current-mode log(x) and log(1/x) functions generator
NASA Astrophysics Data System (ADS)
Al-Absi, Munir A.; Al-Tamimi, Karama M.
2014-08-01
A novel Complementary Metal Oxide Semiconductor (CMOS) current-mode low-voltage and low-power controllable logarithmic function circuit is presented. The proposed design utilises one Operational Transconductance Amplifier (OTA) and two PMOS transistors biased in weak inversion region. The proposed design provides high dynamic range, controllable amplitude, high accuracy and is insensitive to temperature variations. The circuit operates on a ±0.6 V power supply and consumes 0.3 μW. The functionality of the proposed circuit was verified using HSPICE with 0.35 μm 2P4M CMOS process technology.
Interactive intelligent remote operations: application to space robotics
NASA Astrophysics Data System (ADS)
Dupuis, Erick; Gillett, G. R.; Boulanger, Pierre; Edwards, Eric; Lipsett, Michael G.
1999-11-01
A set of tolls addressing the problems specific to the control and monitoring of remote robotic systems from extreme distances has been developed. The tools include the capability to model and visualize the remote environment, to generate and edit complex task scripts, to execute the scripts to supervisory control mode and to monitor and diagnostic equipment from multiple remote locations. Two prototype systems are implemented for demonstration. The first demonstration, using a prototype joint design called Dexter, shows the applicability of the approach to space robotic operation in low Earth orbit. The second demonstration uses a remotely controlled excavator in an operational open-pit tar sand mine. This demonstrates that the tools developed can also be used for planetary exploration operations as well as for terrestrial mining applications.
NASA Astrophysics Data System (ADS)
Wang, I.-Ting; Chang, Chih-Cheng; Chiu, Li-Wen; Chou, Teyuh; Hou, Tuo-Hung
2016-09-01
The implementation of highly anticipated hardware neural networks (HNNs) hinges largely on the successful development of a low-power, high-density, and reliable analog electronic synaptic array. In this study, we demonstrate a two-layer Ta/TaO x /TiO2/Ti cross-point synaptic array that emulates the high-density three-dimensional network architecture of human brains. Excellent uniformity and reproducibility among intralayer and interlayer cells were realized. Moreover, at least 50 analog synaptic weight states could be precisely controlled with minimal drifting during a cycling endurance test of 5000 training pulses at an operating voltage of 3 V. We also propose a new state-independent bipolar-pulse-training scheme to improve the linearity of weight updates. The improved linearity considerably enhances the fault tolerance of HNNs, thus improving the training accuracy.
TADIR: ElOp's high-resolution second-generation 480 x 4 TDI thermal imager
NASA Astrophysics Data System (ADS)
Sarusi, Gabby; Ziv, Natan; Zioni, O.; Gaber, J.; Shechterman, Mark S.; Wiess, I.; Friedland, Igor V.; Lerner, M.; Friedenberg, Abraham
1998-10-01
'TADIR' is a new high-end thermal imager, developed in El-Op under contract with the Israeli MOD during the last three years. This new second generation thermal imager is based on 480 X 4 TDI MCT detector operated in the 8 - 12 micrometer spectral range. Although the prototype configuration of TADIR was design for the highly demanded light weight low volume and low power air applications, TADIR can be considered as a generic modular technology of which the future El-Op's FLIR applications such as ground fire control system and surveillance systems will be derived from. Besides the detector, what puts the system in the high-end category are the state of the art features implemented in each system's components. This paper describes the system concept and design considerations as well as the anticipated performances. TADIRs fist prototype was demonstrated at the beginning of 1998 and is currently under evaluation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
N /A
This Environmental Assessment (EA) evaluates environmental issues associated with constructing and operating an integrated emissions control system proposed by We Energies and its project partners with cost-shared funding support by DOE. The proposed project would be demonstrated at the existing 90-MW Units 7, 8, and 9 of We Energies' coal-fired Presque Isle Power Plant in Marquette, Michigan. The commercial-scale demonstrate would allow utilities to make decisions regarding the integrated emissions control system as a viable commercial option. DOE's share of the funding for the 5-year demonstration project would be about $25 million, while $25 million would also be provided bymore » We Energies and its project partners. This project was selected by DOE under the Clean Coal Power Initiative (CCPI) for negotiation of a cooperative agreement to demonstrate the integration of technologies to reduce emissions of mercury (Hg) and particulate matter, as well as potentially control sulfur dioxide (SO{sub 2}), oxides of nitrogen (NO{sub x}) and hydrochloric acid (HCl) emissions. DOE's decision is whether or not to fund the project. The EA evaluates the principal environmental issues, including air quality, waste management, and traffic, that could result from construction and operation of the proposed project. The EA also considers two reasonably foreseeable scenarios that could result from the no-action alternative in which DOE would not provide cost-shared funding for the proposed project. Key findings include that potential air quality impacts resulting from the proposed project would generally be beneficial because plantwide air emissions would decrease or continue at the same level. The decrease in stack exit temperature would decrease the plume rise, which could result in increased downwind ground-level concentrations of those air pollutants experience little or no decrease in stack emissions. However, results of air dispersion modeling indicated that no major impacts would be expected relative to Prevention of Significant Deterioration increments and National Ambient Air Quality Standards.« less
xLuna - D emonstrator on ESA Mars Rover
NASA Astrophysics Data System (ADS)
Braga, P.; Henriques, L.; Carvalho, B.; Chevalley, P.; Zulianello, M.
2008-08-01
There is a significant gap between the services offered by existing space qualified Real-Time Operating Systems (RTOS) and those required by the most demanding future space applications. New requirements for autonomy, terrain mapping and navigation, Simultaneous Location and Mapping (SLAM), improvement of the throughput of science tasks, all demand high level services such as file systems or POSIX compliant interfaces. xLuna is an operating system that aims fulfilling these new requirements. Besides providing the typical services that of an RTOS (tasks and interrupts management, timers, message queues, etc), it also includes most of the features available in modern general-purpose operating systems, such as Linux. This paper describes a case study that proposes to demonstrate the usage of xLuna on board a rover currently in use for the development of algorithms in preparation of a mission to Mars.
1990-12-03
The primary objective of the STS-35 mission was round the clock observation of the celestial sphere in ultraviolet and X-Ray astronomy with the Astro-1 observatory which consisted of four telescopes: the Hopkins Ultraviolet Telescope (HUT); the Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE); the Ultraviolet Imaging Telescope (UIT); and the Broad Band X-Ray Telescope (BBXRT). The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Teams of controllers and researchers directed on-orbit science operations, sent commands to the spacecraft, received data from experiments aboard the Space Shuttle, adjusted mission schedules to take advantage of unexpected science opportunities or unexpected results, and worked with crew members to resolve problems with their experiments. Due to loss of data used for pointing and operating the ultraviolet telescopes, MSFC ground teams were forced to aim the telescopes with fine tuning by the flight crew. This photo is an overview of the MSFC Payload Control Room (PCR).
1990-12-02
The primary objective of the STS-35 mission was round the clock observation of the celestial sphere in ultraviolet and X-Ray astronomy with the Astro-1 observatory which consisted of four telescopes: the Hopkins Ultraviolet Telescope (HUT); the Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE); the Ultraviolet Imaging Telescope (UIT); and the Broad Band X-Ray Telescope (BBXRT). The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Teams of controllers and researchers directed on-orbit science operations, sent commands to the spacecraft, received data from experiments aboard the Space Shuttle, adjusted mission schedules to take advantage of unexpected science opportunities or unexpected results, and worked with crew members to resolve problems with their experiments. Due to loss of data used for pointing and operating the ultraviolet telescopes, MSFC ground teams were forced to aim the telescopes with fine tuning by the flight crew. Pictured onboard the shuttle is astronaut Robert Parker using a Manual Pointing Controller (MPC) for the ASTRO-1 mission Instrument Pointing System (IPS).
Space Students Visit MSFC During STS-35 Astro-1 Mission
NASA Technical Reports Server (NTRS)
1990-01-01
The primary objective of the STS-35 mission was round the clock observation of the celestial sphere in ultraviolet and X-Ray astronomy with the Astro-1 observatory which consisted of four telescopes: the Hopkins Ultraviolet Telescope (HUT); the Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE); the Ultraviolet Imaging Telescope (UIT); and the Broad Band X-Ray Telescope (BBXRT). The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Teams of controllers and researchers directed on-orbit science operations, sent commands to the spacecraft, received data from experiments aboard the Space Shuttle, adjusted mission schedules to take advantage of unexpected science opportunities or unexpected results, and worked with crew members to resolve problems with their experiments. This photo is of Space classroom students in the Discovery Optics Lab at MSFC during STS-35, ASTRO-1 mission payload operations.
Low NO/x/ heavy fuel combustor program
NASA Technical Reports Server (NTRS)
Lister, E.; Niedzwiecki, R. W.; Nichols, L.
1980-01-01
The paper deals with the 'Low NO/x/ Heavy Fuel Combustor Program'. Main program objectives are to generate and demonstrate the technology required to develop durable gas turbine combustors for utility and industrial applications, which are capable of sustained, environmentally acceptable operation with minimally processed petroleum residual fuels. The program will focus on 'dry' reductions of oxides of nitrogen (NO/x/), improved combustor durability and satisfactory combustion of minimally processed petroleum residual fuels. Other technology advancements sought include: fuel flexibility for operation with petroleum distillates, blends of petroleum distillates and residual fuels, and synfuels (fuel oils derived from coal or shale); acceptable exhaust emissions of carbon monoxide, unburned hydrocarbons, sulfur oxides and smoke; and retrofit capability to existing engines.
Single-stage-to-orbit: Meeting the challenge
NASA Astrophysics Data System (ADS)
Freeman, Delma C., Jr.; Talay, Theodore A.; Austin, Robert Eugene
1995-10-01
There has been and continues to be significant discussion about the viability of fully reusable, single-stage-to-orbit (SSTO) concepts for delivery of payloads to orbit. Often, these discussions have focused in detail on performance and technology requirements relating to the technical feasibility of the concept, with only broad generalizations on how the SSTO will achieve its economic goals of greatly reduced vehicle ground and flight operations costs. With the current industry and NASA Reusable Launch Vehicle Technology Program efforts underway to mature and demonstrate technologies leading to a viable commercial launch system that also satisfies national needs, achieving acceptable recurring costs becomes a significant challenge. This paper reviews the current status of the Reusable Launch Vehicle Technology Program including the DC-XA, X-33, and X-34 flight systems and associated technology programs. The paper also examines lessons learned from the recently completed DC-X reusable rocket demonstrator program. It examines how these technologies and flight systems address the technical and operability challenges of SSTO whose solutions are necessary to reduce costs. The paper also discusses the management and operational approaches that address the challenge of a new cost-effective, reusable launch vehicle system.
Single-stage-to-orbit — Meeting the challenge
NASA Astrophysics Data System (ADS)
Freeman, Delma C.; Talay, Theodore A.; Austin, Robert Eugene
1996-02-01
There has been and continues to be significant discussion about the viability of fully reusable, single-stage-to-orbit (SSTO) concepts for delivery of payloads to orbit. Often, these discussions have focused in detail on performance and technology requirements relating to the technical feasibility of the concept, with only broad generalizations on how the SSTO will achieve its economic goals of greatly reduced vehicle ground and flight operations costs. With the current industry and NASA Reusable Launch Vehicle Technology Program efforts underway to mature and demonstrate technologies leading to a viable commercial launch system that also satisfies national needs, achieving acceptable recurring costs becomes a significant challenge. This paper reviews the current status of the Reusable Launch Vehicle Technology Program including the DC-XA, X-33, X-34 flight systems and associated technology programs. The paper also examines lessons learned from the recently completed DC-X reusable rocket demonstrator program. It examines how these technologies and flight systems address the technical and operability challenges of SSTO whose solutions are necessary to reduce costs. The paper also discusses the management and operational approaches that address the challenge of a new cost-effective, reusable launch vehicle system.
Effect of Nitrogen Oxides on Elemental Mercury Removal by Nanosized Mineral Sulfide.
Li, Hailong; Zhu, Lei; Wang, Jun; Li, Liqing; Lee, Po-Heng; Feng, Yong; Shih, Kaimin
2017-08-01
Because of its large surface area, nanosized zinc sulfide (Nano-ZnS) has been demonstrated in a previous study to be efficient for removal of elemental mercury (Hg 0 ) from coal combustion flue gas. The excellent mercury adsorption performance of Nano-ZnS was found to be insusceptible to water vapor, sulfur dioxide, and hydrogen chloride. However, nitrogen oxides (NO X ) apparently inhibited mercury removal by Nano-ZnS; this finding was unlike those of many studies on the promotional effect of NO X on Hg 0 removal by other sorbents. The negative effect of NO X on Hg 0 adsorption over Nano-ZnS was systematically investigated in this study. Two mechanisms were identified as primarily responsible for the inhibitive effect of NO X on Hg 0 adsorption over Nano-ZnS: (1) active sulfur sites on Nano-ZnS were oxidized to inactive sulfate by NO X ; and (2) the chemisorbed mercury, i.e., HgS, was reduced to Hg 0 by NO X . This new insight into the role of NO X in Hg 0 adsorption over Nano-ZnS can help to optimize operating conditions, maximize Hg 0 adsorption, and facilitate the application of Nano-ZnS as a superior alternative to activated carbon for Hg 0 removal using existing particulate matter control devices in power plants.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Preynas, M.; Laqua, H. P.; Marsen, S.
The Wendelstein 7-X stellarator is a large nuclear fusion device based at Max-Planck-Institut für Plasmaphysik in Greifswald in Germany. The main plasma heating system for steady state operation in W7-X is electron cyclotron resonance heating (ECRH). During operation, part of plama facing components will be directly heated by the non-absorbed power of 1 MW rf beams of ECRH. In order to avoid damages of such components made of graphite tiles during the first operational phase, a near infra-red video system has been developed as a protective diagnostic for safe and secure ECRH operation. Both the mechanical design housing the cameramore » and the optical system are very flexible and respect the requirements of steady state operation. The full system including data acquisition and control system has been successfully tested in the vacuum vessel, including on-line visualization and data storage of the four cameras equipping the ECRH equatorial launchers of W7-X.« less
Ares I-X Flight Test - On the Fast Track to the Future
NASA Technical Reports Server (NTRS)
Davis, Stephan R.; Robinson, Kimberly F.
2008-01-01
In less than two years, the National Aeronautics and Space Administration (NASA) will launch the Ares I-X mission. This will be the first flight of the Ares I crew launch vehicle, which, together with the Ares V cargo launch vehicle, will send humans to the Moon and beyond. Personnel from the Ares I-X Mission Management Office (MMO) are finalizing designs and fabricating vehicle hardware for an April 2009 launch. Ares I-X will be a suborbital development flight test that will gather critical data about the flight dynamics of the integrated launch vehicle stack; understand how to control its roll during flight; better characterize the severe stage separation environments that the upper stage engine will experience during future flights; and demonstrate the first stage recovery system. NASA also will modify the launch infrastructure and ground and mission operations. The Ares I-X Flight Test Vehicle (FTV) will incorporate flight and mockup hardware similar in mass and weight to the operational vehicle. It will be powered by a four-segment Solid Rocket Booster (SRB), which is currently in Shuttle inventory, and will include a fifth spacer segment and new forward structures to make the booster approximately the same size and weight as the five-segment SRB. The Ares I-X flight profile will closely approximate the flight conditions that the Ares I will experience through Mach 4.5, up to approximately130,OOO feet and through maximum dynamic pressure ("Max Q") of approximately 800 pounds per square foot. Data from the Ares I-X flight will support the Ares I Critical Design Review (CDR), scheduled for 2010. Work continues on Ares I-X design and hardware fabrication. All of the individual elements are undergoing CDRs, followed by an integrated vehicle CDR in March 2008. The various hardware elements are on schedule to begin deliveries to Kennedy Space Center (KSC) in early September 2008.
Proposed Solar Probe telecommunications system concept
NASA Astrophysics Data System (ADS)
Kellogg, K.; Devereaux, A.; Vacchione, J.; Kapoor, V.; Crist, R.
1992-01-01
A proposed telecommunications system concept for NASA's Solar Probe mission is described. Key system requirements include 70 kbps data rate at perihelion and operation at X-band (uplink/downlink) and Ka-band (downlink). A design control table is presented to demonstrate design compliance with telecommunication needs. The Ka-band feed is to be a hexagonal array of 37 active elements, each containing 1/4W HEMT amplifiers. The array is located at the Cassegrain point of a 0.75-m reflector. When compared to the TWTA-based system, the Ka-band active array feed provides advantages of reduced mass, increased dc power efficiency, enhanced reliability, graceful degradation, and reduced volume requirements.
NASA Technical Reports Server (NTRS)
Whiting, Matthew Robert
1996-01-01
The feasibility of augmenting the available yaw control power on the X-31 through differential deflection of the canard surfaces was studied as well as the possibility of using differential canard control to stabilize the X-31 with its vertical tail removed. Wind-tunnel tests and the results of departure criteria and linear analysis showed the destabilizing effect of the reduction of the vertical tail on the X-31. Wind-tunnel testing also showed that differential canard deflection was capable of generating yawing moments of roughly the same magnitude as the thrust vectoring vanes currently in place on the X-31 in the post-stall regime. Analysis showed that the X-31 has sufficient aileron roll control power that with the addition of differential canard as a yaw controller, the wind-axis roll accelerations will remain limited by yaw control authority. It was demonstrated, however, that pitch authority may actually limit the maximum roll rate which can be sustained. A drop model flight test demonstrated that coordinated, wind axis rolls could be performed with roll rates as high as 50 deg/sec (full scale equivalent) at 50 deg angle of attack. Another drop model test was conducted to assess the effect of vertical tail reduction, and an analysis of using differential canard deflection to stabilize the tailless X-31 was performed. The results of six-degree-of-freedom, non-linear simulation tests were correlated with the drop model flights. Simulation studies then showed that the tailless X-31 could be controlled at angles of attack at or above 20 deg using differential canard as the only yaw controller.
29 CFR 1910.306 - Specific purpose equipment and installations.
Code of Federal Regulations, 2010 CFR
2010-07-01
... means required by paragraph (e)(1) of this section. (f) X-Ray equipment. This paragraph applies to X-ray... disconnecting means shall be operable from a location readily accessible from the X-ray control. For equipment... suitable nonmetallic raceways or cable trays; or (C) Wire or cable in suitable metal raceways or metal...
29 CFR 1910.306 - Specific purpose equipment and installations.
Code of Federal Regulations, 2011 CFR
2011-07-01
... means required by paragraph (e)(1) of this section. (f) X-Ray equipment. This paragraph applies to X-ray... disconnecting means shall be operable from a location readily accessible from the X-ray control. For equipment... suitable nonmetallic raceways or cable trays; or (C) Wire or cable in suitable metal raceways or metal...
Optoelectronic frequency discriminated phase tuning technology and its applications
NASA Astrophysics Data System (ADS)
Lin, Gong-Ru; Chang, Yung-Cheng
2000-07-01
By using a phase-tunable optoelectronic phase-locked loop, we are able to continuously change the phase as well as the delay-time of optically distributed microwave clock signals or optical pulse train. The advantages of the proposed technique include such as wide-band operation up to 20GHz, wide-range tuning up to 640 degrees, high tuning resolution of <6x10-2 degree/mV, ultra-low short-term phase fluctuation and drive of 4.7x10-2 degree and 3.4x10- 3 degree/min, good linearity with acceptable deviations, and frequency-independent transferred function with slope of nearly 90 degrees/volt, etc. The novel optoelectronic phase shifter is performed by using a DC-voltage controlled, optoelectronic-mixer-based, frequency-down-converted digital phase-locked-loop. The maximum delay-time is continuously tunable up to 3.9 ns for optical pulses repeated at 500 MHz from a gain-switched laser diode. This corresponds to a delay responsivity of about 0.54 ps/mV. The using of the OEPS as being an optoelectronic delay-time controller for optical pulses is demonstrated with temporal resolution of <0.2 ps. Electro-optic sampling of high-frequency microwave signals by using the in-situ delay-time-tunable pulsed laser as a novel optical probe is primarily reported.
1990-12-12
The primary objective of the STS-35 mission was round the clock observation of the celestial sphere in ultraviolet and X-Ray astronomy with the Astro-1 observatory which consisted of four telescopes: the Hopkins Ultraviolet Telescope (HUT); the Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE); the Ultraviolet Imaging Telescope (UIT); and the Broad Band X-Ray Telescope (BBXRT). The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Teams of controllers and researchers directed on-orbit science operations, sent commands to the spacecraft, received data from experiments aboard the Space Shuttle, adjusted mission schedules to take advantage of unexpected science opportunities or unexpected results, and worked with crew members to resolve problems with their experiments. Due to loss of data used for pointing and operating the ultraviolet telescopes, MSFC ground teams were forced to aim the telescopes with fine tuning by the flight crew. This photo captures the activity of WUPPE data review at the Science Operations Area during the mission.
1990-12-02
The primary objective of the STS-35 mission was round the clock observation of the celestial sphere in ultraviolet and X-Ray astronomy with the Astro-1 observatory which consisted of four telescopes: the Hopkins Ultraviolet Telescope (HUT); the Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE); the Ultraviolet Imaging Telescope (UIT); and the Broad Band X-Ray Telescope (BBXRT). The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Teams of controllers and researchers directed on-orbit science operations, sent commands to the spacecraft, received data from experiments aboard the Space Shuttle, adjusted mission schedules to take advantage of unexpected science opportunities or unexpected results, and worked with crew members to resolve problems with their experiments. Due to loss of data used for pointing and operating the ultraviolet telescopes, MSFC ground teams were forced to aim the telescopes with fine tuning by the flight crew. This photo captures the activity of BBKRT data review in the Science Operations Area during the mission.
Multisource inverse-geometry CT. Part II. X-ray source design and prototype
Neculaes, V. Bogdan; Caiafa, Antonio; Cao, Yang; De Man, Bruno; Edic, Peter M.; Frutschy, Kristopher; Gunturi, Satish; Inzinna, Lou; Reynolds, Joseph; Vermilyea, Mark; Wagner, David; Zhang, Xi; Zou, Yun; Pelc, Norbert J.; Lounsberry, Brian
2016-01-01
Purpose: This paper summarizes the development of a high-power distributed x-ray source, or “multisource,” designed for inverse-geometry computed tomography (CT) applications [see B. De Man et al., “Multisource inverse-geometry CT. Part I. System concept and development,” Med. Phys. 43, 4607–4616 (2016)]. The paper presents the evolution of the source architecture, component design (anode, emitter, beam optics, control electronics, high voltage insulator), and experimental validation. Methods: Dispenser cathode emitters were chosen as electron sources. A modular design was adopted, with eight electron emitters (two rows of four emitters) per module, wherein tungsten targets were brazed onto copper anode blocks—one anode block per module. A specialized ceramic connector provided high voltage standoff capability and cooling oil flow to the anode. A matrix topology and low-noise electronic controls provided switching of the emitters. Results: Four modules (32 x-ray sources in two rows of 16) have been successfully integrated into a single vacuum vessel and operated on an inverse-geometry computed tomography system. Dispenser cathodes provided high beam current (>1000 mA) in pulse mode, and the electrostatic lenses focused the current beam to a small optical focal spot size (0.5 × 1.4 mm). Controlled emitter grid voltage allowed the beam current to be varied for each source, providing the ability to modulate beam current across the fan of the x-ray beam, denoted as a virtual bowtie filter. The custom designed controls achieved x-ray source switching in <1 μs. The cathode-grounded source was operated successfully up to 120 kV. Conclusions: A high-power, distributed x-ray source for inverse-geometry CT applications was successfully designed, fabricated, and operated. Future embodiments may increase the number of spots and utilize fast read out detectors to increase the x-ray flux magnitude further, while still staying within the stationary target inherent thermal limitations. PMID:27487878
Multisource inverse-geometry CT. Part II. X-ray source design and prototype
DOE Office of Scientific and Technical Information (OSTI.GOV)
Neculaes, V. Bogdan, E-mail: neculaes@ge.com; Caia
2016-08-15
Purpose: This paper summarizes the development of a high-power distributed x-ray source, or “multisource,” designed for inverse-geometry computed tomography (CT) applications [see B. De Man et al., “Multisource inverse-geometry CT. Part I. System concept and development,” Med. Phys. 43, 4607–4616 (2016)]. The paper presents the evolution of the source architecture, component design (anode, emitter, beam optics, control electronics, high voltage insulator), and experimental validation. Methods: Dispenser cathode emitters were chosen as electron sources. A modular design was adopted, with eight electron emitters (two rows of four emitters) per module, wherein tungsten targets were brazed onto copper anode blocks—one anode blockmore » per module. A specialized ceramic connector provided high voltage standoff capability and cooling oil flow to the anode. A matrix topology and low-noise electronic controls provided switching of the emitters. Results: Four modules (32 x-ray sources in two rows of 16) have been successfully integrated into a single vacuum vessel and operated on an inverse-geometry computed tomography system. Dispenser cathodes provided high beam current (>1000 mA) in pulse mode, and the electrostatic lenses focused the current beam to a small optical focal spot size (0.5 × 1.4 mm). Controlled emitter grid voltage allowed the beam current to be varied for each source, providing the ability to modulate beam current across the fan of the x-ray beam, denoted as a virtual bowtie filter. The custom designed controls achieved x-ray source switching in <1 μs. The cathode-grounded source was operated successfully up to 120 kV. Conclusions: A high-power, distributed x-ray source for inverse-geometry CT applications was successfully designed, fabricated, and operated. Future embodiments may increase the number of spots and utilize fast read out detectors to increase the x-ray flux magnitude further, while still staying within the stationary target inherent thermal limitations.« less
Lin, Ta-Hui; Huang, Shih-Chien
2012-01-01
HtpX is an integral cytoplasmic membrane metalloprotease well conserved in numerous bacteria. A recent study showed that expression of the Bacillus subtilis htpX gene is under dual negative control by Rok and a novel type of transcriptional regulator, YkrK. Here we report that expression of the B. subtilis htpX gene is strongly heat inducible. Contrary to the previous prediction, ykrK expression has been found to be not subject to autoregulation. We have identified the htpX promoter and the authentic ykrK promoter, which is also distinct from the previously predicted one. We have redefined a conserved inverted repeat sequence to be the YkrK operator, which is somewhat different from the previously proposed one. We provide evidence that YkrK is not a substrate of HtpX and that heat induction of htpX is not YkrK mediated. We have also found that the absence of FtsH or HtpX alone did not impair B. subtilis cell viability on LB agar plates at high temperature, whereas the absence of both FtsH and HtpX caused a severe growth defect under heat stress. This finding supports the notion that FtsH and HtpX may have partially overlapping functions in heat resistance. Finally, we show that htpX expression is subject to transient negative control by sigB under heat stress in a Rok- and YkrK-independent manner. Triple negative control of htpX expression at high temperature by rok, sigB, and ykrK may help cells to prevent uncontrolled and detrimental oversynthesis of the HtpX protease. PMID:23042994
The Galactic Center View with Simbol-X
NASA Astrophysics Data System (ADS)
Raimondi, L.; Malaguti, G.; Angelini, L.; Cappi, M.; Grandi, P.; Palumbo, G. G. C.; Puccetti, S.
2009-05-01
The nature of the hard X-ray emission above 3 keV of the Galactic Centre (GC) is still source of controversy. Recent observations with Chandra are consistent with either a population of discrete sources or with a diffuse non thermal emission or, most likely, a combination of the two. The Simbol-X mission will be equipped with a grazing incident telescope imaging up to ~80 keV, providing an improvement of three orders of magnitude in sensitivity and angular resolution compared with the instruments that have operated so far above 10 keV. This capability will enable to directly disentangle between the discrete source versus the diffuse emission scenarios. This is demonstrated by the Simbol-X simulations of the GC shown here, where the input model includes a list of both diffuse and point sources (both resolved and unresolved) using the input spectrum observed with presently operating X-ray telescopes.
1988-07-29
NOTICE OF RADAR S EIlS OR STATU5 vIA COIdWNICATIONS STATUS CHAINC-ES AI.I.2.5 I ICT AS S y F - RECEIVE NOTICE CC• COM ’-NICAT ION STATUS NECESSARY TO...R Ii i I 1 ,I.2.2.2 REVIEW POTENTIAl. CONFLICT SITUATION FOR RES0,UTION X X X , i 2.1.8 DETERMINE APPROPRIATE ACTION ID RESOLVE CUNFLICf I IX XNXx X...SELECTION OF THE SELLCT AUTOMA1IC HANDOFF FUNrIION. A1.4.13 ESTABLISHING, N/A MAINTAINING. AND TERMINATING RADIO COM •LNICATIONS 41.4.13.1 RECEIVE REQUES1 TO
1990-12-03
The primary objective of the STS-35 mission was round the clock observation of the celestial sphere in ultraviolet and X-Ray astronomy with the Astro-1 observatory which consisted of four telescopes: the Hopkins Ultraviolet Telescope (HUT); the Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE); the Ultraviolet Imaging Telescope (UIT); and the Broad Band X-Ray Telescope (BBXRT). The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Teams of controllers and researchers directed on-orbit science operations, sent commands to the spacecraft, received data from experiments aboard the Space Shuttle, adjusted mission schedules to take advantage of unexpected science opportunities or unexpected results, and worked with crew members to resolve problems with their experiments. Pictured is Jack Jones in the Mission Manager Area.
1990-12-03
The primary objective of the STS-35 mission was round the clock observation of the celestial sphere in ultraviolet and X-Ray astronomy with the Astro-1 observatory which consisted of four telescopes: the Hopkins Ultraviolet Telescope (HUT); the Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE); the Ultraviolet Imaging Telescope (UIT); and the Broad Band X-Ray Telescope (BBXRT). The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Teams of controllers and researchers directed on-orbit science operations, sent commands to the spacecraft, received data from experiments aboard the Space Shuttle, adjusted mission schedules to take advantage of unexpected science opportunities or unexpected results, and worked with crew members to resolve problems with their experiments. Pictured is the TV OPS area of the SL POCC.
A hard X-ray nanoprobe beamline for nanoscale microscopy
Winarski, Robert P.; Holt, Martin V.; Rose, Volker; Fuesz, Peter; Carbaugh, Dean; Benson, Christa; Shu, Deming; Kline, David; Stephenson, G. Brian; McNulty, Ian; Maser, Jörg
2012-01-01
The Hard X-ray Nanoprobe Beamline (or Nanoprobe Beamline) is an X-ray microscopy facility incorporating diffraction, fluorescence and full-field imaging capabilities designed and operated by the Center for Nanoscale Materials and the Advanced Photon Source at Sector 26 of the Advanced Photon Source at Argonne National Laboratory. This facility was constructed to probe the nanoscale structure of biological, environmental and material sciences samples. The beamline provides intense focused X-rays to the Hard X-ray Nanoprobe (or Nanoprobe) which incorporates Fresnel zone plate optics and a precision laser sensing and control system. The beamline operates over X-ray energies from 3 to 30 keV, enabling studies of most elements in the periodic table, with a particular emphasis on imaging transition metals. PMID:23093770
Kreller, Cortney R.; Spernjak, Dusan; Li, Wenxia; ...
2014-08-12
Meeting EPA Tier 3 emissions reduction requirements while simultaneously increasing fuel economy to meet new CAFE standards will require optimization of advanced combustion strategies and emissions control technologies. There is an immediate need for suitable exhaust gas sensor technologies to monitor internal combustion engine tailpipe emissions and to control and maintain efficient operation of the engine and exhaust after treatment systems. NH 3, NO x, and HC sensors could enable onboard diagnostics and combustion control in lean-burn engines, analogous to the role of O 2 sensors in stoichiometric burn engines. Commercial manufacturing methods have been used to fabricate self-heated mixed-potentialmore » sensors in a planar automotive configuration. By altering materials composition and operating conditions, we are able to obtain sensitivity/selectivity to each NH 3, NO x and HCs. In addition, these devices exhibit stable performance over months of testing as a result of the stable morphology of the electrode/electrolyte/gas three-phase interface.« less
NASA Technical Reports Server (NTRS)
2005-01-01
An operational change made recently in the drive motor system for the 8- by 6-Foot Supersonic Wind Tunnel (8x6 SWT)/9- by 15-Foot Low-Speed Wind Tunnel (9x15 LSWT) complex resulted in dramatic power savings and expanded operating range. The 8x6 SWT/9x15 LSWT complex offers a unique combination of wind tunnel conditions for both high- and low-speed testing. Prior to the work discussed in this article, the 8- by 6-ft test section offered airflows ranging from Mach 0.36 to 2.0. Subsonic testing was done in the 9-ft high, 15-ft wide test area in the return leg of the facility. The air speed in this test section can range from 0 to 175 mph (Mach 0.23). In the past, we varied the air speed by using a combination of the compressor speed and the position of the tunnel flow-control doors. When very slow speeds were required in the 9x15 LSWT, these large tunnel flow control doors might be very nearly full open, bleeding off large quantities of air, even with the drive system operating at its previous minimum speed of about 510 rpm. Power drawn during this mode of operation varied between 15 and 18 MW/hr, but clearly much of this power was not being used to provide air that would be used for testing in the test section. The air exiting these large doors represented wasted power. Early this year, the facility's tunnel drive system was run on one motor instead of three to see if lower drive speeds could be achieved that would, in turn, result in large power savings because unnecessary air would not be blown out of the flow-control doors unnecessarily. In addition, if the drive could be run slower, then slower speeds would also be possible in the 8x6 SWT test section as an added benefit. Results of the first tests performed early last year showed that in fact the drive, when operating on only one motor, actually reached a steady-state speed of only 337 rpm and drew an amazingly small 6 MW/hr of electrical power. During daytime operation of the drive, this meant that it would be possible to save as much as 10 MW/hr, or nearly $600 per hour of operation, for many of the 9x15 LSWT's testing regimes. An added benefit of this power-saving venture was that since the 8x6 SWT and 9x15 LSWT are indeed on a common loop, if the compressor is slowed down to benefit the 9x15 LSWT, then the air moving through the 8x6 SWT is also moving slower than ever before. In fact, testing has proven that the 8x6 SWT can now achieve Mach 0.25, whereas its previous lower limit was Mach 0.36. This added benefit has attracted additional customers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Smith, L.L.; Hooper, M.
This report summarizes the activities and results for the second testing phase (Phase 2) of an Innovative Clean Coal Technology (ICCT) demonstration of advanced tangentially fired combustion techniques for the reduction of nitrogen oxide (NOx) emissions from coal-fired boilers. All three levels of Asea Brown Boveri Combustion Engineering Service`s (ABB CE`s) Low-NO{sub x} Concentric Firing System (LNCFS) are being demonstrated during this project. The primary goal of this project is to demonstrate the NO{sub x} emissions characteristics of these technologies when operated under normal load dispatched conditions. The equipment is being tested at Gulf Power Company`s Plant Lansing Smith Unitmore » 2 in Lynn Haven, Florida. The long-term NO{sub x} emission trends were documented while the unit was operating under normal load dispatch conditions with the LNCFS Level II equipment. Fifty-five days of long-term data were collected. The data included the effects of mill patterns, unit load, mill outages, weather, fuel variability, and load swings. Test results indicated full-load (180 MW) NO{sub x} emissions of 0.39 lb/MBtu, which is about equal to the short-term test results. At 110 MW, long-term NO{sub x} emissions increased to 0.42 lb/MBtu, which are slightly higher than the short-term data. At 75 MW, NO{sub x} emissions were 0.51 lb/MBtu, which is significantly higher than the short-term data. The annual and 30-day average achievable NOx emissions were determined to be 0.41 and 0.45 lb/MBtu, respectively, for long-term testing load scenarios. NO{sub x} emissions were reduced by a maximum of 40 percent when compared to the baseline data collected in the previous phase. The long-term NO{sub x} reduction at full load (180 MW) was 37 percent while NO{sub x} reduction at low load was minimal.« less
Performance Test of the Next Generation X-Ray Beam Position Monitor System for The APS Upgrade
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yang, B.; Lee, S.; Westferro, F.
The Advanced Photon Source is developing its next major upgrade (APS-U) based on the multi-bend achromat lattice. Improved beam stability is critical for the upgrade and will require keeping short-time beam angle change below 0.25 µrad and long-term angle drift below 0.6 µrad. A reliable white x-ray beam diagnostic system in the front end will be a key part of the planned beam stabilization system. This system includes an x-ray beam position monitor (XBPM) based on x-ray fluorescence (XRF) from two specially designed GlidCop A-15 absorbers, a second XBPM using XRF photons from the Exit Mask, and two white beammore » intensity monitors using XRF from the photon shutter and Compton-scattered photons from the front end beryllium window or a retractable diamond film in windowless front ends. We present orbit stability data for the first XBPM used in the feedback control during user operations, as well as test data from the second XBPM and the intensity monitors. They demonstrate that the XBPM system meets APS-U beam stability requirements.« less
Proceedings of the 20th International Symposium on Space Flight Dynamics
NASA Technical Reports Server (NTRS)
Woodard, Mark (Editor); Stengle, Tom (Editor)
2007-01-01
Topics include: Measuring Image Navigation and Registration Performance at the 3-Sigma Level Using Platinum Quality Landmarks; Flight Dynamics Performances of the MetOp A Satellite during the First Months of Operations; Visual Navigation - SARE Mission; Determining a Method of Enabling and Disabling the Integral Torque in the SDO Science and Inertial Mode Controllers; Guaranteeing Pointing Performance of the SDO Sun-Pointing Controllers in Light of Nonlinear Effects; SDO Delta H Mode Design and Analysis; Observing Mode Attitude Controller for the Lunar Reconnaissance Orbiter; Broken-Plane Maneuver Applications for Earth to Mars Trajectories; ExoMars Mission Analysis and Design - Launch, Cruise and Arrival Analyses; Mars Reconnaissance Orbiter Aerobraking Daily Operations and Collision Avoidance; Mars Reconnaissance Orbiter Interplanetary Cruise Navigation; Motion Parameters Determination of the SC and Phobos in the Project Phobos-Grunt; GRAS NRT Precise Orbit Determination: Operational Experience; Orbit Determination of LEO Satellites for a Single Pass through a Radar: Comparison of Methods; Orbit Determination System for Low Earth Orbit Satellites; Precise Orbit Determination for ALOS; Anti-Collision Function Design and Performances of the CNES Formation Flying Experiment on the PRISMA Mission; CNES Approaching Guidance Experiment within FFIORD; Maneuver Recovery Analysis for the Magnetospheric Multiscale Mission; SIMBOL-X: A Formation Flying Mission on HEO for Exploring the Universe; Spaceborne Autonomous and Ground Based Relative Orbit Control for the TerraSAR-X/TanDEM-X Formation; First In-Orbit Experience of TerraSAR-X Flight Dynamics Operations; Automated Target Planning for FUSE Using the SOVA Algorithm; Space Technology 5 Post-Launch Ground Attitude Estimation Experience; Standardizing Navigation Data: A Status Update; and A Study into the Method of Precise Orbit Determination of a HEO Orbiter by GPS and Accelerometer.
2007-11-01
KENNEDY SPACE CENTER, FLA. -- At ground-breaking ceremonies for SpaceX's new Falcon 9 rocket launch facilities at Space Launch Complex 40 at Cape Canaveral, Elon Musk, founder and CEO of Space Exploration Technologies, talks about opportunity for both SpaceX and the 45th Space Wing that the new facility will provide. As part of NASA’s Commercial Orbital Transportation Services, or COTS, competition, SpaceX will launch a Falcon 9 with a cargo-carrying payload on a series of three demonstration missions from Cape Canaveral to the International Space Station, culminating with the delivery of supplies to the $100 billion dollar orbiting laboratory. SpaceX intends to demonstrate its launch, maneuvering, berthing and return abilities by 2009 – a year before NASA has scheduled the conclusion of Space Shuttle operations. Photo credit: NASA/George Shelton
Round, A. R.; Franke, D.; Moritz, S.; Huchler, R.; Fritsche, M.; Malthan, D.; Klaering, R.; Svergun, D. I.; Roessle, M.
2008-01-01
There is a rapidly increasing interest in the use of synchrotron small-angle X-ray scattering (SAXS) for large-scale studies of biological macromolecules in solution, and this requires an adequate means of automating the experiment. A prototype has been developed of an automated sample changer for solution SAXS, where the solutions are kept in thermostatically controlled well plates allowing for operation with up to 192 samples. The measuring protocol involves controlled loading of protein solutions and matching buffers, followed by cleaning and drying of the cell between measurements. The system was installed and tested at the X33 beamline of the EMBL, at the storage ring DORIS-III (DESY, Hamburg), where it was used by over 50 external groups during 2007. At X33, a throughput of approximately 12 samples per hour, with a failure rate of sample loading of less than 0.5%, was observed. The feedback from users indicates that the ease of use and reliability of the user operation at the beamline were greatly improved compared with the manual filling mode. The changer is controlled by a client–server-based network protocol, locally and remotely. During the testing phase, the changer was operated in an attended mode to assess its reliability and convenience. Full integration with the beamline control software, allowing for automated data collection of all samples loaded into the machine with remote control from the user, is presently being implemented. The approach reported is not limited to synchrotron-based SAXS but can also be used on laboratory and neutron sources. PMID:25484841
Utility gas turbine combustor viewing system: Volume 2, Engine operating envelope test: Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Morey, W.W.
1988-12-01
This report summarizes the development and field testing of a combustor viewing probe (CVP) as a flame diagnostic monitor for utility gas turbine engines. The prototype system is capable of providing a visual record of combustor flame images, recording flame spectral data, analyzing image and spectral data, and diagnosing certain engine malfunctions. The system should provide useful diagnostic information to utility plant operators, and reduced maintenance costs. The field tests demonstrated the ability of the CVP to monitor combustor flame condition and to relate changes in the engine operation with variations in the flame signature. Engine light off, run upmore » to full speed, the addition of load, and the effect of water injection for NO/sub x/ control could easily be identified on the video monitor. The viewing probe was also valuable in identifying hard startups and shutdowns, as well as transient effects that can seriously harm the engine.« less
Construction continues on the RLV complex at the Shuttle Landing Facility
NASA Technical Reports Server (NTRS)
1999-01-01
Construction is under way for the X-33/X-34 hangar complex near the Shuttle Landing Facility at KSC. The Reusable Launch Vehicle (RLV) complex will include facilities for related ground support equipment and administrative/ technical support. It will be available to accommodate the Space Shuttle; the X-34 RLV technology demonstrator; the L-1011 carrier aircraft for Pegasus and X-34; and other RLV and X-vehicle programs. The complex is jointly funded by the Spaceport Florida Authority, NASA's Space Shuttle Program and KSC. The facility will be operational in early 2000.
MEMS phase former kit for high-resolution wavefront control
NASA Astrophysics Data System (ADS)
Gehner, Andreas; Wildenhain, Michael; Neumann, Hannes; Elgner, Andreas; Schenk, Harald
2005-08-01
The MEMS Phase Former Kit developed by the Fraunhofer IPMS is a complete Spatial Light Modulator system based on a piston-type Micro Mirror Array (MMA) for the use in high-resolution, high-speed optical phase control. It has been designed for an easy system integration into an user-specific environment to offer a platform for first practical investigations to open up new applications in Adaptive Optics. The key component is a fine segmented 240 x 200 array of 40 μm piston-type mirror elements capable of 400 nm analog deflection for a 2pi phase modulation in the visible. Each mirror can be addressed and deflected independently by means of an integrated CMOS backplane address circuitry at an 8bit height resolution. Full user programmability and control is provided by a newly developed comfortable driver software for Windows XP based PCs supporting both a Graphical User Interface (GUI) for stand-alone operation with pre-defined data patterns as well as an open ActiveX programming interface for a closed-loop operation with real-time data from an external source. An IEEE1394a FireWire interface is used for high-speed data communication with an electronic driving board performing the actual MMA programming and control allowing for an overall frame rate of up to 500 Hz. Successful proof-of-concept demonstrations already have been given for eye aberration correction in ophthalmology, for error compensation of leightweight primary mirrors of future space telescopes and for ultra-short laser pulse shaping. Besides a presentation of the basic device concept and system architecture the paper will give an overview of the obtained results from these applications.
Band-Gap Engineering at a Semiconductor-Crystalline Oxide Interface
Jahangir-Moghadam, Mohammadreza; Ahmadi-Majlan, Kamyar; Shen, Xuan; ...
2015-02-09
The epitaxial growth of crystalline oxides on semiconductors provides a pathway to introduce new functionalities to semiconductor devices. Key to integrating the functionalities of oxides onto semiconductors is controlling the band alignment at interfaces between the two materials. Here we apply principles of band gap engineering traditionally used at heterojunctions between conventional semiconductors to control the band offset between a single crystalline oxide and a semiconductor. Reactive molecular beam epitaxy is used to realize atomically abrupt and structurally coherent interfaces between SrZr xTi 1-xO₃ and Ge, in which the band gap of the former is enhanced with Zr content x.more » We present structural and electrical characterization of SrZr xTi 1-xO₃-Ge heterojunctions and demonstrate a type-I band offset can be achieved. These results demonstrate that band gap engineering can be exploited to realize functional semiconductor crystalline oxide heterojunctions.« less
Norton, Peter G; Murray, Michael; Doupe, Malcolm B; Cummings, Greta G; Poss, Jeff W; Squires, Janet E; Teare, Gary F; Estabrooks, Carole A
2014-01-01
Objectives To demonstrate the benefit of defining operational management units in nursing homes and computing quality indicators on these units as well as on the whole facility. Design Calculation of adjusted Resident Assessment Instrument – Minimum Data Set 2.0 (RAI–MDS 2.0) quality indicators for: PRU05 (prevalence of residents with a stage 2–4 pressure ulcer), PAI0X (prevalence of residents with pain) and DRG01 (prevalence of residents receiving an antipsychotic with no diagnosis of psychosis), for quarterly assessments between 2007 and 2011 at unit and facility levels. Comparisons of these risk-adjusted quality indicators using statistical process control (control charts). Setting A representative sample of 30 urban nursing homes in the three Canadian Prairie Provinces. Measurements Explicit decision rules were developed and tested to determine whether the control charts demonstrated improving, worsening, unchanging or unclassifiable trends over the time period. Unit and facility performance were compared. Results In 48.9% of the units studied, unit control chart performance indicated different changes in quality over the reporting period than did the facility chart. Examples are provided to illustrate that these differences lead to quite different quality interventions. Conclusions Our results demonstrate the necessity of considering facility-level and unit-level measurement when calculating quality indicators derived from the RAI–MDS 2.0 data, and quite probably from any RAI measures. PMID:24523428
Reconfigurable Flight Control Designs With Application to the X-33 Vehicle
NASA Technical Reports Server (NTRS)
Burken, John J.; Lu, Ping; Wu, Zhenglu
1999-01-01
Two methods for control system reconfiguration have been investigated. The first method is a robust servomechanism control approach (optimal tracking problem) that is a generalization of the classical proportional-plus-integral control to multiple input-multiple output systems. The second method is a control-allocation approach based on a quadratic programming formulation. A globally convergent fixed-point iteration algorithm has been developed to make onboard implementation of this method feasible. These methods have been applied to reconfigurable entry flight control design for the X-33 vehicle. Examples presented demonstrate simultaneous tracking of angle-of-attack and roll angle commands during failures of the right body flap actuator. Although simulations demonstrate success of the first method in most cases, the control-allocation method appears to provide uniformly better performance in all cases.
40 CFR 63.4291 - What are my options for meeting the emission limits?
Code of Federal Regulations, 2010 CFR
2010-07-01
... emission capture systems and add-on controls, the organic HAP emission rate for the web coating/printing... demonstrate that all capture systems and control devices for the web coating/printing operation(s) meet the... capture systems and control devices for the web coating/printing operation(s) meet the operating limits...
High duty cycle inverse Compton scattering X-ray source
Ovodenko, A.; Agustsson, R.; Babzien, M.; ...
2016-12-22
Inverse Compton Scattering (ICS) is an emerging compact X-ray source technology, where the small source size and high spectral brightness are of interest for multitude of applications. However, to satisfy the practical flux requirements, a high-repetition-rate ICS system needs to be developed. To this end, this article reports the experimental demonstration of a high peak brightness ICS source operating in a burst mode at 40 MHz. A pulse train interaction has been achieved by recirculating a picosecond CO 2 laser pulse inside an active optical cavity synchronized to the electron beam. The pulse train ICS performance has been characterized atmore » 5- and 15- pulses per train and compared to a single pulse operation under the same operating conditions. Lastly, with the observed near-linear X-ray photon yield gain due to recirculation, as well as noticeably higher operational reliability, the burst-mode ICS offers a great potential for practical scalability towards high duty cycles.« less
Magnetoelectric confinement and stabilization of Z pinch in a soft-x-ray Ar(+8) laser.
Szasz, J; Kiss, M; Santa, I; Szatmari, S; Kukhlevsky, S V
2013-05-03
Magnetoelectric confinement and stabilization of the plasma column in a soft-x-ray Ar(+8) laser, which is excited by a capillary Z pinch, via the combined magnetic and electric fields of the gliding surface discharge is experimentally demonstrated. Unlike soft-x-ray lasers excited by the conventional capillary Z pinches, the magnetoelectric confinement and stabilization of plasma do provide the laser operation without using any external preionization circuit.
X-29 in Protective Cover Being Transported by Truck to Dryden
NASA Technical Reports Server (NTRS)
1988-01-01
In a stark juxtaposition of nature and technology, the second X-29 forward-swept-wing research aircraft is shown here passing by one of the classic, spiny Joshua trees that populate the Mojave desert while being transported by truck to NASA's Ames-Dryden Flight Research Facility (later the Dryden Flight Research Center), Edwards, California, on November 7, 1988. The aircraft, with its protective covering, traveled by ship from the manufacturer's plant on Long Island through the Panama Canal to Port Hueneme and then was trucked to Dryden. X-29 No. 2 was used in a high angle-of-attack research program which began in spring 1989. Two X-29 aircraft, featuring one of the most unusual designs in aviation history, flew at the Ames-Dryden Flight Research Facility (now the Dryden Flight Research Center, Edwards, California) from 1984 to 1992. The fighter-sized X-29 technology demonstrators explored several concepts and technologies including: the use of advanced composites in aircraft construction; variable-camber wing surfaces; a unique forward- swept wing and its thin supercritical airfoil; strakes; close-coupled canards; and a computerized fly-by-wire flight control system used to maintain control of the otherwise unstable aircraft. Research results showed that the configuration of forward-swept wings, coupled with movable canards, gave pilots excellent control response at angles of attack of up to 45 degrees. During its flight history, the X-29 aircraft flew 422 research missions and a total of 436 missions. Sixty of the research flights were part of the X-29 follow-on 'vortex control' phase. The forward-swept wing of the X-29 resulted in reverse airflow, toward the fuselage rather than away from it, as occurs on the usual aft-swept wing. Consequently, on the forward-swept wing, the ailerons remained unstalled at high angles of attack. This provided better airflow over the ailerons and prevented stalling (loss of lift) at high angles of attack. Introduction of composite materials in the 1970s opened a new field of aircraft construction. It also made possible the construction of the X-29's thin supercritical wing. State-of-the-art composites allowed aeroelastic tailoring which, in turn, allowed the wing some bending but limited twisting and eliminated structural divergence within the flight envelope (i.e. deformation of the wing or the wing breaking off in flight). Additionally, composite materials allowed the wing to be sufficiently rigid for safe flight without adding an unacceptable weight penalty. The X-29 project consisted of two phases plus the follow-on vortex-control phase. Phase 1 demonstrated that the forward sweep of the X-29 wings kept the wing tips unstalled at the moderate angles of attack flown in that phase (a maximum of 21 degrees). Phase I also demonstrated that the aeroelastic tailored wing prevented structural divergence of the wing within the flight envelope, and that the control laws and control-surface effectiveness were adequate to provide artificial stability for an otherwise unstable aircraft. Phase 1 further demonstrated that the X-29 configuration could fly safely and reliably, even in tight turns. During Phase 2 of the project, the X-29, flying at an angle of attack of up to 67 degrees, demonstrated much better control and maneuvering qualities than computational methods and simulation models had predicted . During 120 research flights in this phase, NASA, Air Force, and Grumman project pilots reported the X-29 aircraft had excellent control response to an angle of attack of 45 degrees and still had limited controllability at a 67-degree angle of attack. This controllability at high angles of attack can be attributed to the aircraft's unique forward-swept wing- canard design. The NASA/Air Force-designed high-gain flight control laws also contributed to the good flying qualities. During the Air Force-initiated vortex-control phase, the X-29 successfully demonstrated vortex flow control (VFC). This VFC was more effective than expected in generating yaw forces, especially in high angles of attack where the rudder is less effective. VFC was less effective in providing control when sideslip (wind pushing on the side of the aircraft) was present, and it did little to decrease rocking oscillation of the aircraft. The X-29 vehicle was a single-engine aircraft, 48.1 feet long with a wing span of 27.2 feet. Each aircraft was powered by a General Electric F404-GE-400 engine producing 16,000 pounds of thrust. The program was a joint effort of the Department of Defense's Defense Advanced Research Projects Agency (DARPA), the U.S. Air Force, the Ames-Dryden Flight Research Facility, the Air Force Flight Test Center, and the Grumman Corporation. The program was managed by the Air Force's Wright Laboratory, Wright Patterson Air Force Base, Ohio.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Carnegie Mellon University
2008-09-30
Carnegie Mellon University (CMU) under contract from Department of Energy/National Energy Technology Laboratory (DoE/NETL) and co-funding from the Northeast Gas Association (NGA), has completed the overall system design, field-trial and Magnetic Flux Leakage (MFL) sensor evaluation program for the next-generation Explorer-II (X-II) live gas main Non-destructive Evaluation (NDE) and visual inspection robot platform. The design is based on the Explorer-I prototype which was built and field-tested under a prior (also DoE- and NGA co-funded) program, and served as the validation that self-powered robots under wireless control could access and navigate live natural gas distribution mains. The X-II system design ({approx}8more » ft. and 66 lbs.) was heavily based on the X-I design, yet was substantially expanded to allow the addition of NDE sensor systems (while retaining its visual inspection capability), making it a modular system, and expanding its ability to operate at pressures up to 750 psig (high-pressure and unpiggable steel-pipe distribution mains). A new electronics architecture and on-board software kernel were added to again improve system performance. A locating sonde system was integrated to allow for absolute position-referencing during inspection (coupled with external differential GPS) and emergency-locating. The power system was upgraded to utilize lithium-based battery-cells for an increase in mission-time. The resulting robot-train system with CAD renderings of the individual modules. The system architecture now relies on a dual set of end camera-modules to house the 32-bit processors (Single-Board Computer or SBC) as well as the imaging and wireless (off-board) and CAN-based (on-board) communication hardware and software systems (as well as the sonde-coil and -electronics). The drive-module (2 ea.) are still responsible for bracing (and centering) to drive in push/pull fashion the robot train into and through the pipes and obstacles. The steering modules and their arrangement, still allow the robot to configure itself to perform any-angle (up to 90 deg) turns in any orientation (incl. vertical), and enable the live launching and recovery of the system using custom fittings and a (to be developed) launch-chamber/-tube. The battery modules are used to power the system, by providing power to the robot's bus. The support modules perform the functions of centration for the rest of the train as well as odometry pickups using incremental encoding schemes. The electronics architecture is based on a distributed (8-bit) microprocessor architecture (at least 1 in ea. module) communicating to a (one of two) 32-bit SBC, which manages all video-processing, posture and motion control as well as CAN and wireless communications. The operator controls the entire system from an off-board (laptop) controller, which is in constant wireless communication with the robot train in the pipe. The sensor modules collect data and forward it to the robot operator computer (via the CAN-wireless communications chain), who then transfers it to a dedicated NDE data-storage and post-processing computer for further (real-time or off-line) analysis. The prototype robot system was built and tested indoors and outdoors, outfitted with a Remote-Field Eddy Current (RFEC) sensor integrated as its main NDE sensor modality. An angled launcher, allowing for live launching and retrieval, was also built to suit custom angled launch-fittings from TDW. The prototype vehicle and launcher systems are shown. The complete system, including the in-pipe robot train, launcher, integrated NDE-sensor and real-time video and control console and NDE-data collection and -processing and real-time display, were demonstrated to all sponsors prior to proceeding into final field-trials--the individual components and setting for said acceptance demonstration are shown. The launcher-tube was also used to verify that the vehicle system is capable of operating in high-pressure environments, and is safely deployable using proper evacuating/purging techniques for operation in the potentially explosive natural gas environment. The test-setting and environment for safety-certification of the X-II robot platform and the launch and recovery procedures, is shown. Field-trials were successfully carried out in a live steel pipeline in Northwestern Pennsylvania. The robot was launched and recovered multiple times, travelling thousands of feet and communicating in real time with video and command-and-control (C&C) data under remote operator control from a laptop, with NDE sensor-data streaming to a second computer for storage, display and post-processing. Representative images of the activities and systems used in the week-long field-trial are shown. CMU also evaluated the ability of the X-II design to be able to integrate an MFL sensor, by adding additional drive-/battery-/steering- and support-modules to extend the X-II train.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
1996-07-01
This Public Design Report presents the design criteria of a DOE Innovative Clean Coal Technology (ICCT) project demonstrating advanced wall-fired combustion techniques for the reduction of NO{sub x} emissions from coal-fired boilers. The project is being conducted at Georgia Power Company`s Plant Hammond Unit 4 (500 MW) near Rome, Georgia. The technologies being demonstrated at this site include Foster Wheeler Energy Corporation`s advanced overfire air system and Controlled Flow/Split Flame low NO{sub x} burner. This report provides documentation on the design criteria used in the performance of this project as it pertains to the scope involved with the low NO{submore » x} burners, advanced overfire systems, and digital control system.« less
1995-05-18
U.S. and German personnel of the X-31 Enhanced Fighter Maneuverability Technology Demonstrator aircraft program removing the right wing of the aircraft, which was ferried from Edwards Air Force Base, California, to Europe on May 22, 1995 aboard an Air Force Reserve C-5 transport. The X-31, based at the NASA Dryden Flight Research Center was ferried to Europe and flown in the Paris Air Show in June. The wing of the X-31 was removed on May 18, 1995, to allow the aircraft to fit inside the C-5 fuselage. Officials of the X-31 project used Manching, Germany, as a staging base to prepare the aircraft for the flight demonstration. At the air show, the X-31 demonstrated the value of using thrust vectoring (directing engine exhaust flow) coupled with advanced flight control systems to provide controlled flight at very high angles of attack. The aircraft arrived back at Edwards in a Air Force Reserve C-5 on June 25, 1995 and off loaded at Dryden June 27. The X-31 aircraft was developed jointly by Rockwell International's North American Aircraft Division (now part of Boeing) and Daimler-Benz Aerospace (formerly Messerschmitt-Bolkow-Blohm), under sponsorship by the U.S. Department of Defense and the German Federal Ministry of Defense.
Quantum one-way permutation over the finite field of two elements
NASA Astrophysics Data System (ADS)
de Castro, Alexandre
2017-06-01
In quantum cryptography, a one-way permutation is a bounded unitary operator U:{H} → {H} on a Hilbert space {H} that is easy to compute on every input, but hard to invert given the image of a random input. Levin (Probl Inf Transm 39(1):92-103, 2003) has conjectured that the unitary transformation g(a,x)=(a,f(x)+ax), where f is any length-preserving function and a,x \\in {GF}_{{2}^{\\Vert x\\Vert }}, is an information-theoretically secure operator within a polynomial factor. Here, we show that Levin's one-way permutation is provably secure because its output values are four maximally entangled two-qubit states, and whose probability of factoring them approaches zero faster than the multiplicative inverse of any positive polynomial poly( x) over the Boolean ring of all subsets of x. Our results demonstrate through well-known theorems that existence of classical one-way functions implies existence of a universal quantum one-way permutation that cannot be inverted in subexponential time in the worst case.
NASA Astrophysics Data System (ADS)
Bautz, Mark W.; Kissel, S. E.; Ryu, K.; Suntharalingam, V.
2014-01-01
Silicon X-ray detectors require optical blocking filters to prevent out-of-band (UV, visible and near-IR) radiation from corrupting the X-ray signal. Traditionally, blocking filters have been deposited on thin, free-standing membranes suspended over the detector. Free-standing filters are fragile, however, and in past instruments have required heavy and complex vacuum housings to protect them from acoustic loads during ground operations and launch. A directly-deposited blocking filter greatly simplifies the instrument and in principle permits better soft X-ray detection efficiency than a traditional free-standing filter. Directly-deposited filters have flown in previous generation instruments (e.g. the XMM/Newton Reflection Grating Spectrometer) but none has yet been demonstrated on a modern, high-performance back-illuminated X-ray CCD. We report here on the status of our NASA-funded Strategic Astrophysics Technology program to demonstrate such filters.
Boeing's STAR-FODB test results
NASA Astrophysics Data System (ADS)
Fritz, Martin E.; de la Chapelle, Michael; Van Ausdal, Arthur W.
1995-05-01
Boeing has successfully concluded a 2 1/2 year, two phase developmental contract for the STAR-Fiber Optic Data Bus (FODB) that is intended for future space-based applications. The first phase included system analysis, trade studies, behavior modeling, and architecture and protocal selection. During this phase we selected AS4074 Linear Token Passing Bus (LTPB) protocol operating at 200 Mbps, along with the passive, star-coupled fiber media. The second phase involved design, build, integration, and performance and environmental test of brassboard hardware. The resulting brassboard hardware successfully passed performance testing, providing 200 Mbps operation with a 32 X 32 star-coupled medium. This hardware is suitable for a spaceflight experiment to validate ground testing and analysis and to demonstrate performace in the intended environment. The fiber bus interface unit (FBIU) is a multichip module containing transceiver, protocol, and data formatting chips, buffer memory, and a station management controller. The FBIU has been designed for low power, high reliability, and radiation tolerance. Nine FBIUs were built and integrated with the fiber optic physical layer consisting of the fiber cable plant (FCP) and star coupler assembly (SCA). Performance and environmental testing, including radiation exposure, was performed on selected FBIUs and the physical layer. The integrated system was demonstrated with a full motion color video image transfer across the bus while simultaneously performing utility functions with a fiber bus control module (FBCM) over a telemetry and control (T&C) bus, in this case AS1773.
Graphene oxide windows for in situ environmental cell photoelectron spectroscopy.
Kolmakov, Andrei; Dikin, Dmitriy A; Cote, Laura J; Huang, Jiaxing; Abyaneh, Majid Kazemian; Amati, Matteo; Gregoratti, Luca; Günther, Sebastian; Kiskinova, Maya
2011-08-28
The performance of new materials and devices often depends on processes taking place at the interface between an active solid element and the environment (such as air, water or other fluids). Understanding and controlling such interfacial processes require surface-specific spectroscopic information acquired under real-world operating conditions, which can be challenging because standard approaches such as X-ray photoelectron spectroscopy generally require high-vacuum conditions. The state-of-the-art approach to this problem relies on unique and expensive apparatus including electron analysers coupled with sophisticated differentially pumped lenses. Here, we develop a simple environmental cell with graphene oxide windows that are transparent to low-energy electrons (down to 400 eV), and demonstrate the feasibility of X-ray photoelectron spectroscopy measurements on model samples such as gold nanoparticles and aqueous salt solution placed on the back side of a window. These proof-of-principle results show the potential of using graphene oxide, graphene and other emerging ultrathin membrane windows for the fabrication of low-cost, single-use environmental cells compatible with commercial X-ray and Auger microprobes as well as scanning or transmission electron microscopes.
Triantafyllopoulos, Georgios; Katsaounis, Dimitrios; Karamitros, Dimitrios; Ntziachristos, Leonidas; Samaras, Zissis
2018-03-15
The objective of this study was to test the potential for NO x emissions improvements on a typical Euro 6 diesel vehicle, following modifications to its emissions control system, under Real Drive Emissions (RDE) testing conditions. A commercially available car was selected and was first measured in its original configuration according to RDE on the road and an initial conformity factor (CF) of 5.4 was determined. Subsequent engine calibration and installation of a Selective Catalytic Reduction (SCR) device were conducted and tested on a fully transient engine dyno setup, which precisely reproduced the engine operation under the on-road RDE test. The NO x reduction achieved with those upgrades was 90%, leading to a CF of 0.53, with no CO 2 or fuel consumption penalty. These findings demonstrate that diesel vehicles can reach low NO x levels under real world driving conditions, when well-designed modern exhaust aftertreatment components are installed and properly calibrated. Copyright © 2017 Elsevier B.V. All rights reserved.
Sprint: The first flight demonstration of the external work system robots
NASA Technical Reports Server (NTRS)
Price, Charles R.; Grimm, Keith
1995-01-01
The External Works Systems (EWS) 'X Program' is a new NASA initiative that will, in the next ten years, develop a new generation of space robots for active and participative support of zero g external operations. The robotic development will center on three areas: the assistant robot, the associate robot, and the surrogate robot that will support external vehicular activities (EVA) prior to and after, during, and instead of space-suited human external activities respectively. The EWS robotics program will be a combination of technology developments and flight demonstrations for operational proof of concept. The first EWS flight will be a flying camera called 'Sprint' that will seek to demonstrate operationally flexible, remote viewing capability for EVA operations, inspections, and contingencies for the space shuttle and space station. This paper describes the need for Sprint and its characteristics.
Telescience Resource Kit (TReK)
NASA Technical Reports Server (NTRS)
Lippincott, Jeff
2015-01-01
Telescience Resource Kit (TReK) is one of the Huntsville Operations Support Center (HOSC) remote operations solutions. It can be used to monitor and control International Space Station (ISS) payloads from anywhere in the world. It is comprised of a suite of software applications and libraries that provide generic data system capabilities and access to HOSC services. The TReK Software has been operational since 2000. A new cross-platform version of TReK is under development. The new software is being released in phases during the 2014-2016 timeframe. The TReK Release 3.x series of software is the original TReK software that has been operational since 2000. This software runs on Windows. It contains capabilities to support traditional telemetry and commanding using CCSDS (Consultative Committee for Space Data Systems) packets. The TReK Release 4.x series of software is the new cross platform software. It runs on Windows and Linux. The new TReK software will support communication using standard IP protocols and traditional telemetry and commanding. All the software listed above is compatible and can be installed and run together on Windows. The new TReK software contains a suite of software that can be used by payload developers on the ground and onboard (TReK Toolkit). TReK Toolkit is a suite of lightweight libraries and utility applications for use onboard and on the ground. TReK Desktop is the full suite of TReK software -most useful on the ground. When TReK Desktop is released, the TReK installation program will provide the option to choose just the TReK Toolkit portion of the software or the full TReK Desktop suite. The ISS program is providing the TReK Toolkit software as a generic flight software capability offered as a standard service to payloads. TReK Software Verification was conducted during the April/May 2015 timeframe. Payload teams using the TReK software onboard can reference the TReK software verification. TReK will be demonstrated on-orbit running on an ISS provided T61p laptop. Target Timeframe: September 2015 -2016. The on-orbit demonstration will collect benchmark metrics, and will be used in the future to provide live demonstrations during ISS Payload Conferences. Benchmark metrics and demonstrations will address the protocols described in SSP 52050-0047 Ku Forward section 3.3.7. (Associated term: CCSDS File Delivery Protocol (CFDP)).
The NASA Integrated Vehicle Health Management Technology Experiment for X-37
NASA Technical Reports Server (NTRS)
Schwabacher, Mark; Samuels, Jeff; Brownston, Lee; Clancy, Daniel (Technical Monitor)
2002-01-01
The NASA Integrated Vehicle Health Management (IVHM) Technology Experiment for X-37 was intended to run IVHM software on-board the X-37 spacecraft. The X-37 is intended to be an unpiloted vehicle that would orbit the Earth for up to 21 days before landing on a runway. The objectives of the experiment were to demonstrate the benefits of in-flight IVHM to the operation of a Reusable Launch Vehicle, to advance the Technology Readiness Level of this IVHM technology within a flight environment, and to demonstrate that the IVHM software could operate on the Vehicle Management Computer. The scope of the experiment was to perform real-time fault detection and isolation for X-37's electrical power system and electro-mechanical actuators. The experiment used Livingstone, a software system that performs diagnosis using a qualitative, model-based reasoning approach that searches system-wide interactions to detect and isolate failures. Two of the challenges we faced were to make this research software more efficient so that it would fit within the limited computational resources that were available to us on the X-37 spacecraft, and to modify it so that it satisfied the X-37's software safety requirements. Although the experiment is currently unfunded, the development effort had value in that it resulted in major improvements in Livingstone's efficiency and safety. This paper reviews some of the details of the modeling and integration efforts, and some of the lessons that were learned.
NASA Technical Reports Server (NTRS)
Thomas, R. L.; Richards, T. R.
1977-01-01
The ERDA/NASA 100 kW Mod-0 wind turbine is operating at the NASA Plum Brook Station near Sandusky, Ohio. The operation of the wind turbine has been fully demonstrated and includes start-up, synchronization to the utility network, blade pitch control for control of power and speed, and shut-down. Also, fully automatic operation has been demonstrated by use of a remote control panel, 50 miles from the site, similar to what a utility dispatcher might use. The operation systems and experience with the wind turbine loads, electrical power and aerodynamic performance obtained from testing are described.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1992-05-01
The objective of this project is to demonstrate and evaluate commercially available Selective Catalytic Reduction (SCR) catalysts from US, Japanese and European catalyst suppliers on a high-sulfur US coal-fired boiler. SCR is a post-combustion nitrogen oxide (NO{sub x}) control technology that involves injecting ammonia into the flue gas generated from coal combustion in an electric utility boiler. The flue gas containing ammonia is then passed through a reactor that contains a specialized catalyst. In the presence of the catalyst, the amonia reacts with NO{sub x} to convert it to nitrogen and water vapor. Although SCR is widely practiced in Japanmore » and Europe, there are numerous technical uncertainties associated with applying SCR to US coals. These uncertainties include: (1) potential catalyst deactivation due to poisoning by trace metal species present in US coals that are not present in other fuels. (2) performance of the technology and effects on the balance-of-plant equipment in the presence of high amounts of SO, and SO{sub 3}. (3) performance of a wide variety of SCR catalyst compositions, geometries and methods of manufacture under typical high-sulfur coal-fired utility operating conditions. These uncertainties will be explored by constructing a series of small-scale SCR reactors and simultaneously exposing different SCR catalysts to flue gas derived from the combustion of high sulfur US coal. The demonstration will be performed at Gulf Power Company`s Plant Crist Unit No. 5 (75 MW capacity) near Pensacola, Florida. The project will be funded by the US Department of Energy (DOE), Southern Company Services, Inc. (SCS on behalf of the entire Southern electric system), and the Electric Power Research Institute.« less
NASA Astrophysics Data System (ADS)
Missous, M.; Mitchell, C.; Sly, J.; Lai, K. T.; Gupta, R.; Haywood, S. K.
2004-01-01
Highly strained quantum cascade laser (QCL) and quantum well infrared photodetector (QWIPs) structures based on InxGa(1-x)As-InyAl(1-y)As (x>0.8,y<0.3) layers have been grown by molecular beam epitaxy. Conditions of exact stoichiometric growth were used at a temperature of ∼420°C to produce structures that are suitable for both emission and detection in the 2- 5 μm mid-infrared regime. High structural integrity, as assessed by double crystal X-ray diffraction, room temperature photoluminescence and electrical characteristics were observed. Strong room temperature intersubband absorption in highly tensile strained and strain-compensated In 0.84Ga 0.16As/AlAs/In 0.52Al 0.48As double barrier quantum wells grown on InP substrates is demonstrated. Γ- Γ intersubband transitions have been observed across a wide range of the mid-infrared spectrum (2- 7 μm) in three structures of differing In 0.84Ga 0.16As well width (30, 45, and 80 Å). We demonstrate short-wavelength IR, intersubband operation in both detection and emission for application in QC and QWIP structures. By pushing the InGaAs-InAlAs system to its ultimate limit, we have obtained the highest band offsets that are theoretically possible in this system both for the Γ- Γ bands and the Γ-X bands, thereby opening up the way for both high power and high efficiency coupled with short-wavelength operation at room temperature. The versatility of this material system and technique in covering a wide range of the infrared spectrum is thus demonstrated.
New developments in flash radiography
NASA Astrophysics Data System (ADS)
Mattsson, Arne
2007-01-01
The paper will review some of the latest developments in flash radiography. A series of multi anode tubes has been developed. These are tubes with several x-ray sources within the same vacuum enclosure. The x-ray sources are closely spaced, to come as close as possible to a single source. The x-ray sources are sequentially pulsed, at times that can be independently chosen. Tubes for voltages in the range 150 - 500 kV, with up to eight x-ray sources, will be described. Combining a multi anode tube with an intensified CCD camera, will make it possible to generate short "x-ray movies". A new flash x-ray control system has been developed. The system is operated from a PC or Laptop. All parameters of a multi channel flash x-ray system can be remotely set and monitored. The system will automatically store important operation parameters.
Western Aeronautical Test Range (WATR) Mission Control Gold Room During X-29 Flight
NASA Technical Reports Server (NTRS)
1989-01-01
The mission control Gold room is seen here during a research flight of the X-29 at the Dryden Flight Research Center, Edwards, California. All aspects of a research mission are monitored from one of two of these control rooms at Dryden. Dryden and its control rooms are part of the Western Aeronautical Test Range (WATR). The WATR consists of a highly automated complex of computer controlled tracking, telemetry, and communications systems and control room complexes that are capable of supporting any type of mission ranging from system and component testing, to sub-scale and full-scale flight tests of new aircraft and reentry systems. Designated areas are assigned for spin/dive tests; corridors are provided for low, medium, and high-altitude supersonic flight; and special STOL/VSTOL facilities are available at Ames Moffett and Crows Landing. Special use airspace, available at Edwards, covers approximately twelve thousand square miles of mostly desert area. The southern boundary lies to the south of Rogers Dry Lake, the western boundary lies midway between Mojave and Bakersfield, the northern boundary passes just south of Bishop, and the eastern boundary follows about 25 miles west of the Nevada border except in the northern areas where it crosses into Nevada. Two X-29 aircraft, featuring one of the most unusual designs in aviation history, flew at the Ames-Dryden Flight Research Facility (now the Dryden Flight Research Center, Edwards, California) from 1984 to 1992. The fighter-sized X-29 technology demonstrators explored several concepts and technologies including: the use of advanced composites in aircraft construction; variable-camber wing surfaces; a unique forward- swept wing and its thin supercritical airfoil; strakes; close-coupled canards; and a computerized fly-by-wire flight control system used to maintain control of the otherwise unstable aircraft. Research results showed that the configuration of forward-swept wings, coupled with movable canards, gave pilots excellent control response at angles of attack of up to 45 degrees. During its flight history, the X-29 aircraft flew 422 research missions and a total of 436 missions. Sixty of the research flights were part of the X-29 follow-on 'vortex control' phase. The forward-swept wing of the X-29 resulted in reverse airflow, toward the fuselage rather than away from it, as occurs on the usual aft-swept wing. Consequently, on the forward-swept wing, the ailerons remained unstalled at high angles of attack. This provided better airflow over the ailerons and prevented stalling (loss of lift) at high angles of attack. Introduction of composite materials in the 1970s opened a new field of aircraft construction. It also made possible the construction of the X-29's thin supercritical wing. State-of-the-art composites allowed aeroelastic tailoring which, in turn, allowed the wing some bending but limited twisting and eliminated structural divergence within the flight envelope (i.e. deformation of the wing or the wing breaking off in flight). Additionally, composite materials allowed the wing to be sufficiently rigid for safe flight without adding an unacceptable weight penalty. The X-29 project consisted of two phases plus the follow-on vortex-control phase. Phase 1 demonstrated that the forward sweep of the X-29 wings kept the wing tips unstalled at the moderate angles of attack flown in that phase (a maximum of 21 degrees). Phase I also demonstrated that the aeroelastic tailored wing prevented structural divergence of the wing within the flight envelope, and that the control laws and control-surface effectiveness were adequate to provide artificial stability for an otherwise unstable aircraft. Phase 1 further demonstrated that the X-29 configuration could fly safely and reliably, even in tight turns. During Phase 2 of the project, the X-29, flying at an angle of attack of up to 67 degrees, demonstrated much better control and maneuvering qualities than computational methods and simulation models had predicted . During 120 research flights in this phase, NASA, Air Force, and Grumman project pilots reported the X-29 aircraft had excellent control response to an angle of attack of 45 degrees and still had limited controllability at a 67-degree angle of attack. This controllability at high angles of attack can be attributed to the aircraft's unique forward-swept wing- canard design. The NASA/Air Force-designed high-gain flight control laws also contributed to the good flying qualities. During the Air Force-initiated vortex-control phase, the X-29 successfully demonstrated vortex flow control (VFC). This VFC was more effective than expected in generating yaw forces, especially in high angles of attack where the rudder is less effective. VFC was less effective in providing control when sideslip (wind pushing on the side of the aircraft) was present, and it did little to decrease rocking oscillation of the aircraft. The X-29 vehicle was a single-engine aircraft, 48.1 feet long with a wing span of 27.2 feet. Each aircraft was powered by a General Electric F404-GE-400 engine producing 16,000 pounds of thrust. The program was a joint effort of the Department of Defense's Defense Advanced Research Projects Agency (DARPA), the U.S. Air Force, the Ames-Dryden Flight Research Facility, the Air Force Flight Test Center, and the Grumman Corporation. The program was managed by the Air Force's Wright Laboratory, Wright Patterson Air Force Base, Ohio.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Prikhodko, Vitaly Y.; Parks, James E.; Pihl, Josh A.
Lean gasoline engines offer greater fuel economy than common stoichiometric gasoline engines. However, excess oxygen prevents the use of the current three-way catalyst (TWC) to control nitrogen oxide (NO X) emissions in lean exhaust. A passive SCR concept, introduced by General Motors Global R&D, makes use of a TWC that is already onboard to generate NH 3 under slightly rich conditions, which is stored on the downstream SCR. The stored NH 3 is then used to reduce NO X emissions when the engine switches to lean operation. In this work, the effect of engine parameters, such as air-fuel equivalence ratiomore » and spark timing, on NH 3 generation over a commercial Pd-only TWC with no dedicated oxygen storage component was evaluated on a 2.0-liter BMW lean burn gasoline direct injection engine. NO X reduction, NH 3 formation, and reductant utilization processes were evaluated, and fuel efficiency was assessed and compared to the stoichiometric engine operation case. We found air-fuel equivalence ratio to be one of the most important parameters in controlling the NH 3 production; however, the rich operation necessary for NH 3 production results in a fuel consumption penalty. The fuel penalty can be minimized by adjusting spark timing to increase rich-phase engine out NO X emissions and, thereby, NH 3 levels. Additionally, higher engine out NO X during engine load increase to simulate acceleration resulted in additional fuel savings. Ultimately, a 10% fuel consumption benefit was achieved with the passive SCR approach by optimizing rich air-fuel equivalence ratio and spark timing while also utilizing acceleration load conditions.« less
Prikhodko, Vitaly Y.; Parks, James E.; Pihl, Josh A.; ...
2016-02-18
Lean gasoline engines offer greater fuel economy than common stoichiometric gasoline engines. However, excess oxygen prevents the use of the current three-way catalyst (TWC) to control nitrogen oxide (NO X) emissions in lean exhaust. A passive SCR concept, introduced by General Motors Global R&D, makes use of a TWC that is already onboard to generate NH 3 under slightly rich conditions, which is stored on the downstream SCR. The stored NH 3 is then used to reduce NO X emissions when the engine switches to lean operation. In this work, the effect of engine parameters, such as air-fuel equivalence ratiomore » and spark timing, on NH 3 generation over a commercial Pd-only TWC with no dedicated oxygen storage component was evaluated on a 2.0-liter BMW lean burn gasoline direct injection engine. NO X reduction, NH 3 formation, and reductant utilization processes were evaluated, and fuel efficiency was assessed and compared to the stoichiometric engine operation case. We found air-fuel equivalence ratio to be one of the most important parameters in controlling the NH 3 production; however, the rich operation necessary for NH 3 production results in a fuel consumption penalty. The fuel penalty can be minimized by adjusting spark timing to increase rich-phase engine out NO X emissions and, thereby, NH 3 levels. Additionally, higher engine out NO X during engine load increase to simulate acceleration resulted in additional fuel savings. Ultimately, a 10% fuel consumption benefit was achieved with the passive SCR approach by optimizing rich air-fuel equivalence ratio and spark timing while also utilizing acceleration load conditions.« less
Integrated Computer Controlled Glow Discharge Tube
NASA Astrophysics Data System (ADS)
Kaiser, Erik; Post-Zwicker, Andrew
2002-11-01
An "Interactive Plasma Display" was created for the Princeton Plasma Physics Laboratory to demonstrate the characteristics of plasma to various science education outreach programs. From high school students and teachers, to undergraduate students and visitors to the lab, the plasma device will be a key component in advancing the public's basic knowledge of plasma physics. The device is fully computer controlled using LabVIEW, a touchscreen Graphical User Interface [GUI], and a GPIB interface. Utilizing a feedback loop, the display is fully autonomous in controlling pressure, as well as in monitoring the safety aspects of the apparatus. With a digital convectron gauge continuously monitoring pressure, the computer interface analyzes the input signals, while making changes to a digital flow controller. This function works independently of the GUI, allowing the user to simply input and receive a desired pressure; quickly, easily, and intuitively. The discharge tube is a 36" x 4"id glass cylinder with 3" side port. A 3000 volt, 10mA power supply, is used to breakdown the plasma. A 300 turn solenoid was created to demonstrate the magnetic pinching of a plasma. All primary functions of the device are controlled through the GUI digital controllers. This configuration allows for operators to safely control the pressure (100mTorr-1Torr), magnetic field (0-90Gauss, 7amps, 10volts), and finally, the voltage applied across the electrodes (0-3000v, 10mA).
Dense and Sparse Matrix Operations on the Cell Processor
DOE Office of Scientific and Technical Information (OSTI.GOV)
Williams, Samuel W.; Shalf, John; Oliker, Leonid
2005-05-01
The slowing pace of commodity microprocessor performance improvements combined with ever-increasing chip power demands has become of utmost concern to computational scientists. Therefore, the high performance computing community is examining alternative architectures that address the limitations of modern superscalar designs. In this work, we examine STI's forthcoming Cell processor: a novel, low-power architecture that combines a PowerPC core with eight independent SIMD processing units coupled with a software-controlled memory to offer high FLOP/s/Watt. Since neither Cell hardware nor cycle-accurate simulators are currently publicly available, we develop an analytic framework to predict Cell performance on dense and sparse matrix operations, usingmore » a variety of algorithmic approaches. Results demonstrate Cell's potential to deliver more than an order of magnitude better GFLOP/s per watt performance, when compared with the Intel Itanium2 and Cray X1 processors.« less
The JPL telerobot operator control station. Part 1: Hardware
NASA Technical Reports Server (NTRS)
Kan, Edwin P.; Tower, John T.; Hunka, George W.; Vansant, Glenn J.
1989-01-01
The Operator Control Station of the Jet Propulsion Laboratory (JPL)/NASA Telerobot Demonstrator System provides the man-machine interface between the operator and the system. It provides all the hardware and software for accepting human input for the direct and indirect (supervised) manipulation of the robot arms and tools for task execution. Hardware and software are also provided for the display and feedback of information and control data for the operator's consumption and interaction with the task being executed. The hardware design, system architecture, and its integration and interface with the rest of the Telerobot Demonstrator System are discussed.
NASA Astrophysics Data System (ADS)
Hsu, Fang-Yuh; Hsu, Shih-Ming; Chao, Jiunn-Hsing
2017-11-01
The subject of this study is the on-site visits and inspections of facilities commissioned by the Atomic Energy Council (AEC) in Taiwan. This research was conducted to evaluate the possible dose and dose rate of cabinet-type X-ray equipment with nominal voltages of 30-150 kV and open-beam (portable or handheld) equipment, taking both normal operation and possibly abnormal operation conditions into account. Doses and dose rates were measured using a plastic scintillation survey meter and an electronic personal dosimeter. In total, 401 X-ray machines were inspected, including 139 units with nominal voltages of 30-50 kV X-ray equipment, 140 units with nominal voltages of 50-150 kV, and 122 open-beam (portable or handheld) X-ray equipment. The investigated doses for radiation workers and non-radiation workers operating cabinet-type X-ray equipment under normal safety conditions were all at the background dose level. Several investigated dose rates at the position of 10 cm away from the surface of open-beam (portable or handheld) X-ray equipment were very high, such X-ray machines are used by aeronautical police for the detection of suspected explosives, radiation workers are far away (at least 10 m away) from the X-ray machine during its operation. The doses per operation in X-ray equipment with a 30-50 kV nominal voltage were less than 1 mSv in all cases of abnormal use. Some doses were higher than 1 mSv per operation for X-ray equipment of 50-150 kV nominal voltage X-ray. The maximum dose rates at the beam exit have a very wide range, mostly less than 100 μSv/s and the largest value is about 3.92 mSv/s for open-beam (portable or handheld) X-ray devices. The risk induced by operating X-ray devices with nominal voltages of 30-50 kV is extremely low. The 11.5 mSv dose due to one operation at nominal voltage of 50-150 kV X-ray device is equivalent to the exposure of taking 575 chest X-rays. In the abnormal use of open-beam (portable or handheld) X-ray equipment, the effective dose of 3.92 mSv/s is equivalent to taking 196 chest radiographs within 1 s. This work assessed the annual doses (equivalent and effective doses) and risks of X-ray operator staff as reasonably as possible. The results of this research are helpful to the AEC (competent authority of ionization radiation) to improve the management and perform the safe control of X-ray equipment.
Improved charge injection device and a focal plane interface electronics board for stellar tracking
NASA Technical Reports Server (NTRS)
Michon, G. J.; Burke, H. K.
1984-01-01
An improved Charge Injection Device (CID) stellar tracking sensor and an operating sensor in a control/readout electronics board were developed. The sensor consists of a shift register scanned, 256x256 CID array organized for readout of 4x4 subarrays. The 4x4 subarrays can be positioned anywhere within the 256x256 array with a 2 pixel resolution. This allows continuous tracking of a number of stars simultaneously since nine pixels (3x3) centered on any star can always be read out. Organization and operation of this sensor and the improvements in design and semiconductor processing are described. A hermetic package incorporating an internal thermoelectric cooler assembled using low temperature solders was developed. The electronics board, which contains the sensor drivers, amplifiers, sample hold circuits, multiplexer, analog to digital converter, and the sensor temperature control circuits, is also described. Packaged sensors were evaluated for readout efficiency, spectral quantum efficiency, temporal noise, fixed pattern noise, and dark current. Eight sensors along with two tracker electronics boards were completed, evaluated, and delivered.
Theory and Applications of Elliptically Contoured and Related Distributions
1990-09-01
is invariant under n x n orthogonal transfor- mations. When the parent distribution is more generally ECp(pA, X, 4), the c.f. of X is n E(eitrTIX...those properties to some wider class than that of SD? 18 A largest characterization of SD is a demonstration that there is no generating vector Y...Takemura’s Generalizations of Cochran’s Theorem," George P.H. Styan, September 1982. 3. " Some Further Applications of Finite Difference Operators," Kai
Integrated Flight Path Planning System and Flight Control System for Unmanned Helicopters
Jan, Shau Shiun; Lin, Yu Hsiang
2011-01-01
This paper focuses on the design of an integrated navigation and guidance system for unmanned helicopters. The integrated navigation system comprises two systems: the Flight Path Planning System (FPPS) and the Flight Control System (FCS). The FPPS finds the shortest flight path by the A-Star (A*) algorithm in an adaptive manner for different flight conditions, and the FPPS can add a forbidden zone to stop the unmanned helicopter from crossing over into dangerous areas. In this paper, the FPPS computation time is reduced by the multi-resolution scheme, and the flight path quality is improved by the path smoothing methods. Meanwhile, the FCS includes the fuzzy inference systems (FISs) based on the fuzzy logic. By using expert knowledge and experience to train the FIS, the controller can operate the unmanned helicopter without dynamic models. The integrated system of the FPPS and the FCS is aimed at providing navigation and guidance to the mission destination and it is implemented by coupling the flight simulation software, X-Plane, and the computing software, MATLAB. Simulations are performed and shown in real time three-dimensional animations. Finally, the integrated system is demonstrated to work successfully in controlling the unmanned helicopter to operate in various terrains of a digital elevation model (DEM). PMID:22164029
Integrated flight path planning system and flight control system for unmanned helicopters.
Jan, Shau Shiun; Lin, Yu Hsiang
2011-01-01
This paper focuses on the design of an integrated navigation and guidance system for unmanned helicopters. The integrated navigation system comprises two systems: the Flight Path Planning System (FPPS) and the Flight Control System (FCS). The FPPS finds the shortest flight path by the A-Star (A*) algorithm in an adaptive manner for different flight conditions, and the FPPS can add a forbidden zone to stop the unmanned helicopter from crossing over into dangerous areas. In this paper, the FPPS computation time is reduced by the multi-resolution scheme, and the flight path quality is improved by the path smoothing methods. Meanwhile, the FCS includes the fuzzy inference systems (FISs) based on the fuzzy logic. By using expert knowledge and experience to train the FIS, the controller can operate the unmanned helicopter without dynamic models. The integrated system of the FPPS and the FCS is aimed at providing navigation and guidance to the mission destination and it is implemented by coupling the flight simulation software, X-Plane, and the computing software, MATLAB. Simulations are performed and shown in real time three-dimensional animations. Finally, the integrated system is demonstrated to work successfully in controlling the unmanned helicopter to operate in various terrains of a digital elevation model (DEM).
DOE Office of Scientific and Technical Information (OSTI.GOV)
DOE; ORNL; NREL
1999-10-15
The Diesel Emission Control-Sulfur Effects (DECSE) is a joint government/industry program to determine the impact of diesel fuel sulfur levels on emission control systems whose use could lower emissions of nitrogen oxides (NOx) and particulate matter (PM) from on-highway trucks in the 2002--2004 model years. Phase 1 of the program was developed with the following objectives in mind: (1) evaluate the effects of varying the level of sulfur content in the fuel on the emission reduction performance of four emission control technologies; and (2) measure and compare the effects of up to 250 hours of aging on selected devices formore » multiple levels of fuel sulfur content. This interim report discusses the results of the DECSE test program that demonstrates the potential of NOx adsorber catalyst technology across the range of diesel engine operation with a fuel economy penalty less than 4%.« less
1. VIEW OF THE CONTROL ROOM FOR THE XY RETRIEVER. ...
1. VIEW OF THE CONTROL ROOM FOR THE X-Y RETRIEVER. USING THE X-Y RETRIEVER, OPERATORS RETRIEVED PLUTONIUM METAL FROM THE PLUTONIUM STORAGE VAULTS (IN MODULE K) AND CONVEYED IT TO THE X-Y SHUTTLE AREA WHERE IT WAS CUT AND WEIGHED. FROM THE SHUTTLE AREA THE PLUTONIUM WAS CONVEYED TO MODULES A, J OR K FOR CASTING, OR MODULE B FOR ROLLING AND FORMING. (5/17/71) - Rocky Flats Plant, Plutonium Manufacturing Facility, North-central section of Plant, just south of Building 776/777, Golden, Jefferson County, CO
High-flux soft x-ray harmonic generation from ionization-shaped few-cycle laser pulses
Brahms, Christian; Gregory, Andrew; Tisch, John W. G.; Marangos, Jon P.
2018-01-01
Laser-driven high-harmonic generation provides the only demonstrated route to generating stable, tabletop attosecond x-ray pulses but has low flux compared to other x-ray technologies. We show that high-harmonic generation can produce higher photon energies and flux by using higher laser intensities than are typical, strongly ionizing the medium and creating plasma that reshapes the driving laser field. We obtain high harmonics capable of supporting attosecond pulses up to photon energies of 600 eV and a photon flux inside the water window (284 to 540 eV) 10 times higher than previous attosecond sources. We demonstrate that operating in this regime is key for attosecond pulse generation in the x-ray range and will become increasingly important as harmonic generation moves to fields that drive even longer wavelengths. PMID:29756033
[The testing system for OCP of the digital X-ray machine].
Wang, Yan; Mo, Guoming; Wang, Juru; Zhou, Tao; Yu, Jianguo
2011-09-01
In this paper, we designed a testing system for operator control panel of a high-voltage and high-frequency X-ray machine, and an online testing software for functional components, in order to help the testing engineers to improve their work efficiency.
Multiport backside-illuminated CCD imagers for high-frame-rate camera applications
NASA Astrophysics Data System (ADS)
Levine, Peter A.; Sauer, Donald J.; Hseuh, Fu-Lung; Shallcross, Frank V.; Taylor, Gordon C.; Meray, Grazyna M.; Tower, John R.; Harrison, Lorna J.; Lawler, William B.
1994-05-01
Two multiport, second-generation CCD imager designs have been fabricated and successfully tested. They are a 16-port 512 X 512 array and a 32-port 1024 X 1024 array. Both designs are back illuminated, have on-chip CDS, lateral blooming control, and use a split vertical frame transfer architecture with full frame storage. The 512 X 512 device has been operated at rates over 800 frames per second. The 1024 X 1024 device has been operated at rates over 300 frames per second. The major changes incorporated in the second-generation design are, reduction in gate length in the output area to give improved high-clock-rate performance, modified on-chip CDS circuitry for reduced noise, and optimized implants to improve performance of blooming control at lower clock amplitude. This paper discusses the imager design improvements and presents measured performance results at high and moderate frame rates. The design and performance of three moderate frame rate cameras are discussed.
X-43C Flight Demonstrator Project Overview
NASA Technical Reports Server (NTRS)
Moses, Paul L.
2003-01-01
The X-43C Flight Demonstrator Project is a joint NASA-USAF hypersonic propulsion technology flight demonstration project that will expand the hypersonic flight envelope for air-breathing engines. The Project will demonstrate sustained accelerating flight through three flights of expendable X-43C Demonstrator Vehicles (DVs). The approximately 16-foot long X-43C DV will be boosted to the starting test conditions, separate from the booster, and accelerate from Mach 5 to Mach 7 under its own power and autonomous control. The DVs will be powered by a liquid hydrocarbon-fueled, fuel-cooled, dual-mode, airframe integrated scramjet engine system developed under the USAF HyTech Program. The Project is managed by NASA Langley Research Center as part of NASA's Next Generation Launch Technology Program. Flight tests will be conducted by NASA Dryden Flight Research Center off the coast of California over water in the Pacific Test Range. The NASA/USAF/industry project is a natural extension of the Hyper-X Program (X-43A), which will demonstrate short duration (approximately 10 seconds) gaseous hydrogen-fueled scramjet powered flight at Mach 7 and Mach 10 using a heavy-weight, largely heat sink construction, experimental engine. The X-43C Project will demonstrate sustained accelerating flight from Mach 5 to Mach 7 (approximately 4 minutes) using a flight-weight, fuel-cooled, scramjet engine powered by much denser liquid hydrocarbon fuel. The X-43C DV design flows from integrating USAF HyTech developed engine technologies with a NASA Air-Breathing Launch Vehicle accelerator-class configuration and Hyper-X heritage vehicle systems designs. This paper describes the X-43C Project and provides the background for NASA's current hypersonic flight demonstration efforts.
1990-12-04
The primary objective of the STS-35 mission was round the clock observation of the celestial sphere in ultraviolet and X-Ray astronomy with the Astro-1 observatory which consisted of four telescopes: the Hopkins Ultraviolet Telescope (HUT); the Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE); the Ultraviolet Imaging Telescope (UIT); and the Broad Band X-Ray Telescope (BBXRT). The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Teams of controllers and researchers directed on-orbit science operations, sent commands to the spacecraft, received data from experiments aboard the Space Shuttle, adjusted mission schedules to take advantage of unexpected science opportunities or unexpected results, and worked with crew members to resolve problems with their experiments. Due to loss of data used for pointing and operating the ultraviolet telescopes, MSFC ground teams were forced to aim the telescopes with fine tuning by the flight crew. This photo captures a press briefing at MSFC during STS-35, ASTRO-1 Mission.
1990-12-02
The primary objective of the STS-35 mission was round the clock observation of the celestial sphere in ultraviolet and X-Ray astronomy with the Astro-1 observatory which consisted of four telescopes: the Hopkins Ultraviolet Telescope (HUT); the Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE); the Ultraviolet Imaging Telescope (UIT); and the Broad Band X-Ray Telescope (BBXRT). The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Teams of controllers and researchers directed on-orbit science operations, sent commands to the spacecraft, received data from experiments aboard the Space Shuttle, adjusted mission schedules to take advantage of unexpected science opportunities or unexpected results, and worked with crew members to resolve problems with their experiments. Due to loss of data used for pointing and operating the ultraviolet telescopes, MSFC ground teams were forced to aim the telescopes with fine tuning by the flight crew. This photo captures the activity of viewing HUT data in the Mission Manager Actions Room during the mission.
1990-12-02
The primary objective of the STS-35 mission was round the clock observation of the celestial sphere in ultraviolet and X-Ray astronomy with the Astro-1 observatory which consisted of four telescopes: the Hopkins Ultraviolet Telescope (HUT); the Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE); the Ultraviolet Imaging Telescope (UIT); and the Broad Band X-Ray Telescope (BBXRT). The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Teams of controllers and researchers directed on-orbit science operations, sent commands to the spacecraft, received data from experiments aboard the Space Shuttle, adjusted mission schedules to take advantage of unexpected science opportunities or unexpected results, and worked with crew members to resolve problems with their experiments. Due to loss of data used for pointing and operating the ultraviolet telescopes, MSFC ground teams were forced to aim the telescopes with fine tuning by the flight crew. This photo captures the activities at the Mission Manager Actions Room during the mission.
Lemke, John; Sardariani, Edmond; Phipps, Joseph Bradley; Patel, Niki; Itri, Loretta M; Caravelli, James; Viscusi, Eugene R
2016-09-01
Fentanyl iontophoretic transdermal system (fentanyl ITS, IONSYS(®)) is a patient-controlled analgesia system used for the management of acute postoperative pain, designed to be utilized in a hospital setting. The objective of the two studies was to determine if fentanyl ITS could be safely used with X-rays, computerized tomography (CT) scans and radiofrequency identification (RFID) devices. The ITS system has two components: controller and drug unit; the studies utilized ITS systems without fentanyl, referred to as the ITS Placebo system. The first study evaluated the effect of X-radiation on the operation of an ITS Placebo system. Five ITS Placebo systems were exposed to X-rays (20 and 200 mSv total radiation dose-the 200 mSv radiation dose represents a tenfold higher exposure than in clinical practice) while operating in the Ready Mode and five were exposed while operating in the Dose Mode. The second study evaluated the effect of RFID (worst-case scenario of direct contact with an RFID transmitter) on the operation of an ITS Placebo system. During these tests, observations of the user interface and measurements of output voltage confirmed proper function throughout all operational modes (Ready Mode, Dose Mode, End-of-Use Mode, and End-of-Life Mode). The ITS Placebo system met all specifications and no functional anomalies were observed during and following X-ray exposure at two radiation dose levels or exposure at six different combinations of RFID frequencies and field strengths. The performance of the ITS system was unaffected by X-ray exposure levels well beyond those associated with diagnostic X-rays and CT scans, and by exposure to radiofrequency field strengths typically generated by RFID devices. These results provide added confidence to clinicians that the fentanyl ITS system does not need to be removed during diagnostic X-rays and CT scans and can also be utilized in close proximity to RFID devices. The studies and writing of this manuscript were supported financially by The Medicines Company.
STS-35 Mission Manager Actions Room at the Marshall Space Flight Center Spacelab Payload Operations
NASA Technical Reports Server (NTRS)
1990-01-01
The primary objective of the STS-35 mission was round the clock observation of the celestial sphere in ultraviolet and X-Ray astronomy with the Astro-1 observatory which consisted of four telescopes: the Hopkins Ultraviolet Telescope (HUT); the Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE); the Ultraviolet Imaging Telescope (UIT); and the Broad Band X-Ray Telescope (BBXRT). The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Teams of controllers and researchers directed on-orbit science operations, sent commands to the spacecraft, received data from experiments aboard the Space Shuttle, adjusted mission schedules to take advantage of unexpected science opportunities or unexpected results, and worked with crew members to resolve problems with their experiments. Due to loss of data used for pointing and operating the ultraviolet telescopes, MSFC ground teams were forced to aim the telescopes with fine tuning by the flight crew. This photo captures the activities at the Mission Manager Actions Room during the mission.
International Space Station Payload Operations Integration Center (POIC) Overview
NASA Technical Reports Server (NTRS)
Ijames, Gayleen N.
2012-01-01
Objectives and Goals: Maintain and operate the POIC and support integrated Space Station command and control functions. Provide software and hardware systems to support ISS payloads and Shuttle for the POIF cadre, Payload Developers and International Partners. Provide design, development, independent verification &validation, configuration, operational product/system deliveries and maintenance of those systems for telemetry, commanding, database and planning. Provide Backup Control Center for MCC-H in case of shutdown. Provide certified personnel and systems to support 24x7 facility operations per ISS Program. Payloads CoFR Implementation Plan (SSP 52054) and MSFC Payload Operations CoFR Implementation Plan (POIF-1006).
Decision Space Operations: Campaign Design Aimed at an Adversary’s Decision Making
2003-01-01
14 Figure 3: Reflexive control, Initial situation (physical reality ...20 Figure 4: Reflexive control, reality as X imagines it to be...20 Figure 5: Reflexive control, reality as Y imagines it to be .......................................................21 Figure 6: Reflexive
Development of mercuric iodide uncooled x ray detectors and spectrometers
NASA Technical Reports Server (NTRS)
Iwanczyk, Jan S.
1990-01-01
The results obtained in the development of miniature, lowpower, light weight mercuric iodide, HgI2, x ray spectrometers for future space missions are summarized. It was demonstrated that HgI2 detectors can be employed in a high resolution x ray spectrometer, operating in a scanning electron microscope. Also, the development of HgI2 x ray detectors to augment alpha backscattering spectrometers is discussed. These combination instruments allow for the identification of all chemical elements, with the possible exception of hydrogen, and their respective concentrations. Additionally, further investigations of questions regarding radiation damage effects in the HgI2 x ray detectors are reported.
Two dimensional recursive digital filters for near real time image processing
NASA Technical Reports Server (NTRS)
Olson, D.; Sherrod, E.
1980-01-01
A program was designed toward the demonstration of the feasibility of using two dimensional recursive digital filters for subjective image processing applications that require rapid turn around. The concept of the use of a dedicated minicomputer for the processor for this application was demonstrated. The minicomputer used was the HP1000 series E with a RTE 2 disc operating system and 32K words of memory. A Grinnel 256 x 512 x 8 bit display system was used to display the images. Sample images were provided by NASA Goddard on a 800 BPI, 9 track tape. Four 512 x 512 images representing 4 spectral regions of the same scene were provided. These images were filtered with enhancement filters developed during this effort.
TADIR-production version: El-Op's high-resolution 480x4 TDI thermal imaging system
NASA Astrophysics Data System (ADS)
Sarusi, Gabby; Ziv, Natan; Zioni, O.; Gaber, J.; Shechterman, Mark S.; Lerner, M.
1999-07-01
Efforts invested at El-Op during the last four years have led to the development of TADIR - engineering model thermal imager, demonstrated in 1998, and eventually to the final production version of TADIR to be demonstrated in full operation during 1999. Both versions take advantage of the high resolution and high sensitivity obtained by the 480 X 4 TDI MCT detector as well as many more features implemented in the system to obtain a state of the art high- end thermal imager. The production version of TADIR uses a 480 X 6 TDI HgCdTe detector made by the SCD Israeli company. In this paper, we will present the main features of the production version of TADIR.
The X-15 airplane - Lessons learned
NASA Technical Reports Server (NTRS)
Dana, William H.
1993-01-01
The X-15 rocket research airplane flew to an altitude of 354,000 ft and reached Mach 6.70. In almost 200 flights, this airplane was used to gather aerodynamic-heating, structural loads, stability and control, and atmospheric-reentry data. This paper describes the origins, design, and operation of the X-15 airplane. In addition, lessons learned from the X-15 airplane that are applicable to designing and testing the National Aero-Space Plane are discussed.
A CMOS Compatible, Forming Free TaO x ReRAM
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lohn, A. J.; Stevens, J. E.; Mickel, P. R.
2013-08-31
Resistive random access memory (ReRAM) has become a promising candidate for next-generation high-performance non-volatile memory that operates by electrically tuning resistance states via modulating vacancy concentrations. Here, we demonstrate a wafer-scale process for resistive switching in tantalum oxide that is completely CMOS compatible. The resulting devices are forming-free and with greater than 1x10 5 cycle endurance.
Increased Curie Temperature Induced by Orbital Ordering in La0.67Sr0.33MnO3/BaTiO3 Superlattices.
Zhang, Fei; Wu, Biao; Zhou, Guowei; Quan, Zhi-Yong; Xu, Xiao-Hong
2018-01-17
Recent theoretical studies indicated that the Curie temperature of perovskite manganite thin films can be increased by more than an order of magnitude by applying appropriate interfacial strain to control orbital ordering. In this work, we demonstrate that the regular intercalation of BaTiO 3 layers between La 0.67 Sr 0.33 MnO 3 layers effectively enhances ferromagnetic order and increases the Curie temperature of La 0.67 Sr 0.33 MnO 3 /BaTiO 3 superlattices. The preferential orbital occupancy of e g (x 2 -y 2 ) in La 0.67 Sr 0.33 MnO 3 layers induced by the tensile strain of BaTiO 3 layers is identified by X-ray linear dichroism measurements. Our results reveal that controlling orbital ordering can effectively improve the Curie temperature of La 0.67 Sr 0.33 MnO 3 films and that in-plane orbital occupancy is beneficial to the double exchange ferromagnetic coupling of thin-film samples. These findings create new opportunities for the design and control of magnetism in artificial structures and pave the way to a variety of novel magnetoelectronic applications that operate far above room temperature.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gorentla Venkata, Manjunath; Shamis, Pavel; Graham, Richard L
2013-01-01
Many scientific simulations, using the Message Passing Interface (MPI) programming model, are sensitive to the performance and scalability of reduction collective operations such as MPI Allreduce and MPI Reduce. These operations are the most widely used abstractions to perform mathematical operations over all processes that are part of the simulation. In this work, we propose a hierarchical design to implement the reduction operations on multicore systems. This design aims to improve the efficiency of reductions by 1) tailoring the algorithms and customizing the implementations for various communication mechanisms in the system 2) providing the ability to configure the depth ofmore » hierarchy to match the system architecture, and 3) providing the ability to independently progress each of this hierarchy. Using this design, we implement MPI Allreduce and MPI Reduce operations (and its nonblocking variants MPI Iallreduce and MPI Ireduce) for all message sizes, and evaluate on multiple architectures including InfiniBand and Cray XT5. We leverage and enhance our existing infrastructure, Cheetah, which is a framework for implementing hierarchical collective operations to implement these reductions. The experimental results show that the Cheetah reduction operations outperform the production-grade MPI implementations such as Open MPI default, Cray MPI, and MVAPICH2, demonstrating its efficiency, flexibility and portability. On Infini- Band systems, with a microbenchmark, a 512-process Cheetah nonblocking Allreduce and Reduce achieves a speedup of 23x and 10x, respectively, compared to the default Open MPI reductions. The blocking variants of the reduction operations also show similar performance benefits. A 512-process nonblocking Cheetah Allreduce achieves a speedup of 3x, compared to the default MVAPICH2 Allreduce implementation. On a Cray XT5 system, a 6144-process Cheetah Allreduce outperforms the Cray MPI by 145%. The evaluation with an application kernel, Conjugate Gradient solver, shows that the Cheetah reductions speeds up total time to solution by 195%, demonstrating the potential benefits for scientific simulations.« less
Development Of A Dynamic Radiographic Capability Using High-Speed Video
NASA Astrophysics Data System (ADS)
Bryant, Lawrence E.
1985-02-01
High-speed video equipment can be used to optically image up to 2,000 full frames per second or 12,000 partial frames per second. X-ray image intensifiers have historically been used to image radiographic images at 30 frames per second. By combining these two types of equipment, it is possible to perform dynamic x-ray imaging of up to 2,000 full frames per second. The technique has been demonstrated using conventional, industrial x-ray sources such as 150 Kv and 300 Kv constant potential x-ray generators, 2.5 MeV Van de Graaffs, and linear accelerators. A crude form of this high-speed radiographic imaging has been shown to be possible with a cobalt 60 source. Use of a maximum aperture lens makes best use of the available light output from the image intensifier. The x-ray image intensifier input and output fluors decay rapidly enough to allow the high frame rate imaging. Data are presented on the maximum possible video frame rates versus x-ray penetration of various thicknesses of aluminum and steel. Photographs illustrate typical radiographic setups using the high speed imaging method. Video recordings show several demonstrations of this technique with the played-back x-ray images slowed down up to 100 times as compared to the actual event speed. Typical applications include boiling type action of liquids in metal containers, compressor operation with visualization of crankshaft, connecting rod and piston movement and thermal battery operation. An interesting aspect of this technique combines both the optical and x-ray capabilities to observe an object or event with both external and internal details with one camera in a visual mode and the other camera in an x-ray mode. This allows both kinds of video images to appear side by side in a synchronized presentation.
Fourier transform wavefront control with adaptive prediction of the atmosphere.
Poyneer, Lisa A; Macintosh, Bruce A; Véran, Jean-Pierre
2007-09-01
Predictive Fourier control is a temporal power spectral density-based adaptive method for adaptive optics that predicts the atmosphere under the assumption of frozen flow. The predictive controller is based on Kalman filtering and a Fourier decomposition of atmospheric turbulence using the Fourier transform reconstructor. It provides a stable way to compensate for arbitrary numbers of atmospheric layers. For each Fourier mode, efficient and accurate algorithms estimate the necessary atmospheric parameters from closed-loop telemetry and determine the predictive filter, adjusting as conditions change. This prediction improves atmospheric rejection, leading to significant improvements in system performance. For a 48x48 actuator system operating at 2 kHz, five-layer prediction for all modes is achievable in under 2x10(9) floating-point operations/s.
Active control of fan noise from a turbofan engine
NASA Technical Reports Server (NTRS)
Thomas, Russell H.; Burdisso, Ricardo A.; Fuller, Christopher R.; O'Brien, Walter F.
1993-01-01
A three channel active control system is applied to an operational turbofan engine in order to reduce tonal noise produced by both the fan and high pressure compressor. The control approach is the feedforward filtered-x least-mean-square algorithm implemented on a digital signal processing board. Reference transducers mounted on the engine case provides blade passing and harmonics frequency information to the controller. Error information is provided by large area microphones placed in the acoustic far field. In order to minimize the error signal, the controller actuates loudspeakers mounted on the inlet to produce destructive interference. The sound pressure level of the fundamental tone of the fan was reduced using the three channel controller by up to 16 dB over a 60 deg angle about the engine axis. A single channel controller could produce reduction over a 30 deg angle. The experimental results show the control to be robust. Simultaneous control of two tones is done with parallel controllers. The fundamental and the first harmonic tones of the fan were controlled simultaneously with reductions of 12 dBA and 5 dBA, respectively, measured on the engine axis. Simultaneous control was also demonstrated for the fan fundamental and the high pressure compressor fundamental tones.
An Advanced Trajectory-Based Operations Prototype Tool and Focus Group Evaluation
NASA Technical Reports Server (NTRS)
Guerreiro, Nelson M.; Jones, Denise R.; Barmore, Bryan E.; Butler, Ricky W.; Hagen, George E.; Maddalon, Jeffrey M.; Ahmad, Nash'at N.; Rogers, Laura J.; Underwood, Matthew C.; Johnson, Sally C.
2017-01-01
Trajectory-based operations (TBO) is a key concept in the Next Generation Air Transportation System transformation of the National Airspace System (NAS) that will increase the predictability and stability of traffic flows, support a common operational picture through the use of digital data sharing, facilitate more effective collaborative decision making between airspace users and air navigation service providers, and enable increased levels of integrated automation across the NAS. The National Aeronautics and Space Administration (NASA) has been developing trajectory-based systems to improve the efficiency of the NAS during specific phases of flight and is now also exploring Advanced 4-Dimensional Trajectory (4DT) operational concepts that will integrate these technologies and incorporate new technology where needed to create both automation and procedures to support gate-to-gate TBO. A TBO Prototype simulation toolkit has been developed that demonstrates initial functionality that may reside in an Advanced 4DT TBO concept. Pilot and controller subject matter experts (SMEs) were brought to the Air Traffic Operations Laboratory at NASA Langley Research Center for discussions on an Advanced 4DT operational concept and were provided an interactive demonstration of the TBO Prototype using four example scenarios. The SMEs provided feedback on potential operational, technological, and procedural opportunities and concerns. After viewing the interactive demonstration scenarios, the SMEs felt the operational capabilities demonstrated would be useful for performing TBO while maintaining situation awareness and low mental workload. The TBO concept demonstrated produced defined routings around weather which resulted in a more organized, consistent flow of traffic where it was clear to both the controller and pilot what route the aircraft was to follow. In general, the controller SMEs felt that traffic flow management should be responsible for generating and negotiating the operational constraints demonstrated, in cooperation with the Air Traffic Control System Command Center, while air traffic control should be responsible for the implementation of those constraints. The SMEs also indicated that digital data communications would be very beneficial for TBO operations and would result in less workload due to reduced communications, would eliminate issues due to language barriers and frequency problems, and would make receiving, loading, accepting, and executing clearances easier, less ambiguous, and more expeditious. This paper describes an Advanced 4DT operational concept, the TBO Prototype, the demonstration scenarios and methods used, and the feedback obtained from the pilot and controller SMEs in this focus group evaluation.
Approximate controllability of a system of parabolic equations with delay
NASA Astrophysics Data System (ADS)
Carrasco, Alexander; Leiva, Hugo
2008-09-01
In this paper we give necessary and sufficient conditions for the approximate controllability of the following system of parabolic equations with delay: where [Omega] is a bounded domain in , D is an n×n nondiagonal matrix whose eigenvalues are semi-simple with nonnegative real part, the control and B[set membership, variant]L(U,Z) with , . The standard notation zt(x) defines a function from [-[tau],0] to (with x fixed) by zt(x)(s)=z(t+s,x), -[tau][less-than-or-equals, slant]s[less-than-or-equals, slant]0. Here [tau][greater-or-equal, slanted]0 is the maximum delay, which is supposed to be finite. We assume that the operator is linear and bounded, and [phi]0[set membership, variant]Z, [phi][set membership, variant]L2([-[tau],0];Z). To this end: First, we reformulate this system into a standard first-order delay equation. Secondly, the semigroup associated with the first-order delay equation on an appropriate product space is expressed as a series of strongly continuous semigroups and orthogonal projections related with the eigenvalues of the Laplacian operator (); this representation allows us to reduce the controllability of this partial differential equation with delay to a family of ordinary delay equations. Finally, we use the well-known result on the rank condition for the approximate controllability of delay system to derive our main result.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Steiner, Myles A; Perl, Emmett; Simon, John D
We demonstrate dual junction (Al)GaInP/GaAs solar cells that are designed to operate at 400 degrees C and 1000X concentration in a hybrid photovoltaic-solar thermal concentrator system. The cells have a front metallization and anti-reflection coating that are stable under 400 degrees C operation. We show how the cell performance degrades with increasing aluminum compositions in the top cell. Our best cell is a GaInP/GaAs tandem that demonstrated 15+/-1% efficiency at 400 degrees C over a concentration range of 300-1000 suns, with several pathways to improved performance.
Vakarin, Vladyslav; Ramírez, Joan Manel; Frigerio, Jacopo; Ballabio, Andrea; Le Roux, Xavier; Liu, Qiankun; Bouville, David; Vivien, Laurent; Isella, Giovanni; Marris-Morini, Delphine
2017-09-01
This Letter explores the use of Ge-rich Si 0.2 Ge 0.8 waveguides on graded Si 1-x Ge x substrate for the demonstration of ultra-wideband photonic integrated circuits in the mid-infrared (mid-IR) wavelength range. We designed, fabricated, and characterized broadband Mach-Zehnder interferometers fully covering a range of 3 μm in the mid-IR band. The fabricated devices operate indistinctly in quasi-TE and quasi-TM polarizations, and have an extinction ratio higher than 10 dB over the entire operating wavelength range. The obtained results are in good correlation with theoretical predictions, while numerical simulations indicate that the device bandwidth can reach one octave with low additional losses. This Letter paves the way for further realization of mid-IR integrated spectrometers using low-index-contrast Si 1-x Ge x waveguides with high germanium concentration.
Code of Federal Regulations, 2013 CFR
2013-01-01
... flight safety analysis must demonstrate that a launch operator will, for each launch, control the risk to... isolation of the hazards, to demonstrate control of the risk to the public. (1) Risk assessment. When demonstrating control of risk through risk assessment, the analysis must demonstrate that any risk to the public...
Code of Federal Regulations, 2012 CFR
2012-01-01
... flight safety analysis must demonstrate that a launch operator will, for each launch, control the risk to... isolation of the hazards, to demonstrate control of the risk to the public. (1) Risk assessment. When demonstrating control of risk through risk assessment, the analysis must demonstrate that any risk to the public...
Code of Federal Regulations, 2011 CFR
2011-01-01
... flight safety analysis must demonstrate that a launch operator will, for each launch, control the risk to... isolation of the hazards, to demonstrate control of the risk to the public. (1) Risk assessment. When demonstrating control of risk through risk assessment, the analysis must demonstrate that any risk to the public...
Code of Federal Regulations, 2014 CFR
2014-01-01
... flight safety analysis must demonstrate that a launch operator will, for each launch, control the risk to... isolation of the hazards, to demonstrate control of the risk to the public. (1) Risk assessment. When demonstrating control of risk through risk assessment, the analysis must demonstrate that any risk to the public...
Spaceborne Autonomous and Ground Based Relative Orbit Control for the TerraSAR-X/TanDEM-X Formation
NASA Technical Reports Server (NTRS)
Ardaens, J. S.; D'Amico, S.; Kazeminejad, B.; Montenbruck, O.; Gill, E.
2007-01-01
TerraSAR-X (TSX) and TanDEM-X (TDX) are two advanced synthetic aperture radar (SAR) satellites flying in formation. SAR interferometry allows a high resolution imaging of the Earth by processing SAR images obtained from two slightly different orbits. TSX operates as a repeat-pass interferometer in the first phase of its lifetime and will be supplemented after two years by TDX in order to produce digital elevation models (DEM) with unprecedented accuracy. Such a flying formation makes indeed possible a simultaneous interferometric data acquisition characterized by highly flexible baselines with range of variations between a few hundreds meters and several kilometers [1]. TSX has been successfully launched on the 15th of June, 2007. TDX is expected to be launched on the 31st of May, 2009. A safe and robust maintenance of the formation is based on the concept of relative eccentricity/inclination (e/i) vector separation whose efficiency has already been demonstrated during the Gravity Recovery and Climate Experiment (GRACE) [2]. Here, the satellite relative motion is parameterized by mean of relative orbit elements and the key idea is to align the relative eccentricity and inclination vectors to minimize the hazard of a collision. Previous studies have already shown the pertinence of this concept and have described the way of controlling the formation using an impulsive deterministic control law [3]. Despite the completely different relative orbit control requirements, the same approach can be applied to the TSX/TDX formation. The task of TDX is to maintain the close formation configuration by actively controlling its relative motion with respect to TSX, the leader of the formation. TDX must replicate the absolute orbit keeping maneuvers executed by TSX and also compensate the natural deviation of the relative e/i vectors. In fact the relative orbital elements of the formation tend to drift because of the secular non-keplerian perturbations acting on both satellites. The goal of the ground segment is thus to regularly correct this configuration by performing small orbit correction maneuvers on TDX. The ground station contacts are limited due to the geographic position of the station and the costs for contact time. Only with a polar ground station a contact visibility is possible every orbit for LEO satellites. TSX and TDX use only the Weilheim ground station (in the southern part of Germany) during routine operations. This station allows two scheduled contact per day for the nominal orbit configuration, meaning that the satellite conditions can be checked with an interval of 12 hours. While this limitation is usually not critical for single satellite operations, the visibility constraints drive the achievable orbit control accuracy for a LEO formation if a ground based approach is chosen. Along-track position uncertainties and maneuver execution errors affect the relative motion and can be compensated only after a ground station contact.
Demonstration of the feasibility of automated silicon solar cell fabrication
NASA Technical Reports Server (NTRS)
Thornhill, J. W.; Taylor, W. E.
1976-01-01
An analysis of estimated costs indicate that for an annual output of 4,747,000 hexagonal cells (38 mm. on a side) a total factory cost of $0.866 per cell could be achieved. For cells with 14% efficiency at AMO intensity (1353 watts per square meter), this annual production rate is equivalent to 3,373 kilowatts and a manufacturing cost of $1.22 per watt of electrical output. A laboratory model of such a facility was operated to produce a series of demonstration runs, producing hexagonal cells, 2 x 2 cm cells and 2 x 4 cm cells.
NASA Technical Reports Server (NTRS)
Hogenson, P. A.; Lu, Tina
1995-01-01
The objective is to develop the advanced thermal seals to a technology readiness level (TRL) of 6 to support the rapid turnaround time and low maintenance requirements of the X-33 and the future reusable launch vehicle (RLV). This program is divided into three subtasks: (1) orbiter thermal seals operation history review; (2) material, process, and design improvement; and (3) fabrication and evaluation of the advanced thermal seals.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-09-17
..., consented to the indirect transfer of control of the above facility from its current owner, Autoliv to X-Ray Industries, Inc. (X- Ray), (together, the applicants), pursuant to 10 CFR 50.80. By its terms, the Order of...
SpaceX Falcon Heavy Demo Flight - Liftoff
2018-02-06
A SpaceX Falcon Heavy rocket begins its demonstration flight with liftoff at 3:45 p.m. EST from from Launch Complex 39A at NASA's Kennedy Space Center in Florida. This is a significant milestone for the world's premier multi-user spaceport. In 2014, NASA signed a property agreement with SpaceX for the use and operation of the center's pad 39A, where the company has launched Falcon 9 rockets and prepared for the first Falcon Heavy. NASA also has Space Act Agreements in place with partners, such as SpaceX, to provide services needed to process and launch rockets and spacecraft.
Density gradient free electron collisionally excited x-ray laser
Campbell, E.M.; Rosen, M.D.
1984-11-29
An operational x-ray laser is provided that amplifies 3p-3s transition x-ray radiation along an approximately linear path. The x-ray laser is driven by a high power optical laser. The driving line focused optical laser beam illuminates a free-standing thin foil that may be associated with a substrate for improved structural integrity. This illumination produces a generally cylindrically shaped plasma having an essentially uniform electron density and temperature, that exists over a long period of time, and provides the x-ray laser gain medium. The x-ray laser may be driven by more than one optical laser beam. The x-ray laser has been successfully demonstrated to function in a series of experimental tests.
Björklund, K; Kimaro, M; Urassa, E; Lindmark, G
2000-02-01
To determine whether the Misgav Ladach caesarean section technique can offer benefits compared with conventional caesarean section technique in the prevailing conditions of a busy African tertiary centre. A randomised controlled trial. A tertiary African obstetric unit with 18,000 deliveries annually. Three hundred and thirty-nine women undergoing caesarean section. Eight residents and registrars were instructed in the Misgav Ladach technique for caesarean section during one week, after which the study commenced. The course participants instructed their colleagues; in total, 16 doctors participated. Women requiring caesarean section were randomised to Misgav Ladach or to the conventional lower midline incision procedure, excluding those with a previous scar. During 11 weeks 339 randomised procedures (328 of which were emergency procedures) were carried out. Mean operating time was 25 x 3 minutes for Misgav Ladach and 32 x 6 minutes for the lower midline incision procedure (95% CI -8 x 3; -6 x 3). Mean blood loss was 354 mL and 447 mL (-133; -53), and the number of sutures 3 x 1 and 6 x 1 (-3 x 1; -2 x 9), respectively. No significant difference was found in Apgar scores. Mobilisation was earlier with the Misgav Ladach procedure. No difference was found in overall post-operative infection rates i.e. wound infection or febrile illness, but the combination of wound infection and fever was more common in the Misgav Ladach group. The Misgav Ladach caesarean section confers benefits such as reduced blood loss, conservation of time and suture material, and rapid mobilisation, but more studies are needed to explore modifications aimed at reducing post-operative infections in settings with limited resources.
NASA Technical Reports Server (NTRS)
Lee, L. F.; Cooper, L. P.
1993-01-01
This article describes the approach, results, and lessons learned from an applied research project demonstrating how artificial intelligence (AI) technology can be used to improve Deep Space Network operations. Configuring antenna and associated equipment necessary to support a communications link is a time-consuming process. The time spent configuring the equipment is essentially overhead and results in reduced time for actual mission support operations. The NASA Office of Space Communications (Code O) and the NASA Office of Advanced Concepts and Technology (Code C) jointly funded an applied research project to investigate technologies which can be used to reduce configuration time. This resulted in the development and application of AI-based automated operations technology in a prototype system, the Link Monitor and Control Operator Assistant (LMC OA). The LMC OA was tested over the course of three months in a parallel experimental mode on very long baseline interferometry (VLBI) operations at the Goldstone Deep Space Communications Center. The tests demonstrated a 44 percent reduction in pre-calibration time for a VLBI pass on the 70-m antenna. Currently, this technology is being developed further under Research and Technology Operating Plan (RTOP)-72 to demonstrate the applicability of the technology to operations in the entire Deep Space Network.
Conceptual design of the X-IFU Instrument Control Unit on board the ESA Athena mission
NASA Astrophysics Data System (ADS)
Corcione, L.; Ligori, S.; Capobianco, V.; Bonino, D.; Valenziano, L.; Guizzo, G. P.
2016-07-01
Athena is one of L-class missions selected in the ESA Cosmic Vision 2015-2025 program for the science theme of the Hot and Energetic Universe. The Athena model payload includes the X-ray Integral Field Unit (X-IFU), an advanced actively shielded X-ray microcalorimeter spectrometer for high spectral resolution imaging, utilizing cooled Transition Edge Sensors. This paper describes the preliminary architecture of Instrument Control Unit (ICU), which is aimed at operating all XIFU's subsystems, as well as at implementing the main functional interfaces of the instrument with the S/C control unit. The ICU functions include the TC/TM management with S/C, science data formatting and transmission to S/C Mass Memory, housekeeping data handling, time distribution for synchronous operations and the management of the X-IFU components (i.e. CryoCoolers, Filter Wheel, Detector Readout Electronics Event Processor, Power Distribution Unit). ICU functions baseline implementation for the phase-A study foresees the usage of standard and Space-qualified components from the heritage of past and current space missions (e.g. Gaia, Euclid), which currently encompasses Leon2/Leon3 based CPU board and standard Space-qualified interfaces for the exchange commands and data between ICU and X-IFU subsystems. Alternative architecture, arranged around a powerful PowerPC-based CPU, is also briefly presented, with the aim of endowing the system with enhanced hardware resources and processing power capability, for the handling of control and science data processing tasks not defined yet at this stage of the mission study.
NASA Technical Reports Server (NTRS)
Bailey, M. C.
1985-01-01
A 6X6 array of fan-dipoles was designed to operate in the 510 to 660 MHz frequency range for aircraft flight test and evaluation of a UHF radiometer system. A broad-band dipole design operating near the first resonance is detailed. Measured VSWR and radiation patterns for the dipole array demonstrate achievable bandwidths in the 35 percent to 40 percent range.
PLANT-SCALE DEMONSTRATION OF SLUDGE INCINERATOR FUEL REDUCTION
A plant-scale demonstration was conducted on 8 sewage sludge incinerators at Indianapolis, Indiana to reduce fuel consumption. More efficient operating mode of operation was developed, instrumentation and controls were added and an operator training program was conducted to reduc...
NASA Technical Reports Server (NTRS)
Mercer, Joey; Gomez, Ashley; Gabets, Cynthia; Bienert, Nancy; Edwards, Tamsyn; Martin, Lynne; Gujral, Vimmy; Homola, Jeffrey
2016-01-01
To determine the capabilities and limitations of human operators and automation in separation assurance roles, the second of three Human-in-the-Loop (HITL) part-task studies investigated air traffic controllers ability to detect and resolve conflicts under varying task sets, traffic densities, and run lengths. Operations remained within a single sector, staffed by a single controller, and explored, among other things, the controllers responsibility for conflict resolution with or without their involvement in the conflict detection task. Furthermore, these conditions were examined across two different traffic densities; 1x (current-day traffic) and a 20 increase above current-day traffic levels (1.2x). Analyses herein offer an examination of the conflict resolution strategies employed by controllers. In particular, data in the form of elapsed time between conflict detection and conflict resolution are used to assess if, and how, the controllers involvement in the conflict detection task affected the way in which they resolved traffic conflicts.
NASA Technical Reports Server (NTRS)
Bogdan, V. M.
1981-01-01
A proof is given of the existence and uniqueness of the solution to the automatic control problem with a nonlinear state equation of the form y' = f(t,y,u) and nonlinear operator controls u = U(y) acting onto the state function y which satisfies the initial condition y(t) = x(t) for t or = 0.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-05-06
... curing ovens used in wet-laid non-woven fiber mat manufacturing operations when nitrogen containing resins or other additives are used. These two actions affect NO X sources operating in the Dallas Fort...
Remote Observations in the Near Infrared
NASA Astrophysics Data System (ADS)
Gavryusev, V.; Baffa, C.; Giani, E.
We present our experiences in remote observations in Near Infrared bands operating a bidimensional instrument ARNICA. ARNICA, an infrared CCD detector operating at a telescope (TIRGO, Gornergrat, Switzerland) was controlled by an observer from Firenze, Italy. Despite the rather slow Internet link available, we were able to perform the observations in quite an acceptable way. The user interface process (a widget based X11 client) was executed locally on a Sun workstation. All processes responsible for hardware support (initialization of devices and their dynamic control and data acquisition itself) were executed remotely under DESQview/X on a PC dedicated to the control of ARNICA. The traffic was reduced to a minimum due to the truly distributed software used. In normal conditions this is just an exchange of short primitives which describe the task to be performed and of informative messages. There is also the possibility of a continuous display of the obtained images, with flexible control of display parameters.
Adding control to arbitrary unknown quantum operations
Zhou, Xiao-Qi; Ralph, Timothy C.; Kalasuwan, Pruet; Zhang, Mian; Peruzzo, Alberto; Lanyon, Benjamin P.; O'Brien, Jeremy L.
2011-01-01
Although quantum computers promise significant advantages, the complexity of quantum algorithms remains a major technological obstacle. We have developed and demonstrated an architecture-independent technique that simplifies adding control qubits to arbitrary quantum operations—a requirement in many quantum algorithms, simulations and metrology. The technique, which is independent of how the operation is done, does not require knowledge of what the operation is, and largely separates the problems of how to implement a quantum operation in the laboratory and how to add a control. Here, we demonstrate an entanglement-based version in a photonic system, realizing a range of different two-qubit gates with high fidelity. PMID:21811242
2017-12-11
provides ultra-low energy search operations. To improve throughput, the in-array pipeline scheme has been developed, allowing the MeTCAM to operate at a...controlled magnetic tunnel junction (VC-MTJ), which not only reduces cell area (thus achieving higher density) but also eliminates standby energy . This...Variations of the cell design are presented and evaluated. The results indicated a potential 90x improvement in the energy efficiency and a 50x
A study of X-divertor in NSTX-U with SOLPS simulations
NASA Astrophysics Data System (ADS)
Chen, Zhong-Ping; Kotschenreuther, Mike; Mahajan, Swadesh; Gerhardt, Stefan
2018-03-01
The X-divertor (XD) geometry in NSTX-U is demonstrated, via SOLPS simulations, to perform better than the standard divertor (SD); in particular, it allows detachment at a lower upstream density and stabilizes the detachment front near the target, away from the main X-point. Consequently a stable detached operation becomes possible—the localization near the plate allows a vast reduction of heat fluxes without degrading the core plasma. Indeed, it is confirmed by our simulation that at similar states of detachment the XD outperforms the SD by reducing the heat fluxes to the target and maintaining higher upstream temperatures, resulting in scrape-off layers that are more favorable for advanced tokamak operation. These advantages are attributed to the unique geometric characteristics of XD—poloidal flaring near the target.
Enhanced broadband (11-15 µm) QWIP FPAs for space applications
NASA Astrophysics Data System (ADS)
Nedelcu, Alexandru; de l'Isle, Nadia B.; Truffer, Jean-Patrick; Belhaire, Eric; Costard, Eric; Bois, Philippe; Merken, Patrick; Saint-Pé, Olivier
2017-11-01
A thirty months ESA project started in March 2008, whose purpose is to expand and assess the performance of broadband (11-15μm) quantum detectors for spectro-imaging applications: Fourier Transform Spectrometers and Dispersive Spectrometers. We present here the technical requirements, the development approach chosen as well as preliminary signal to noise ratio (SNR) calculations. Our approach is fully compatible with the final array format (1024x256, pitch 50-60μm). We expect the requested uniformity, operability and SNR levels to be achieved at the goal temperatures (60K for FTS applications and 50K for DS applications). The performance level will be demonstrated on 256x256, 50μm pitch arrays. Also, operability and uniformity issues will be addressed on large mechanical 1024x256 hybrid arrays.
Qian, Xin; Tucker, Andrew; Gidcumb, Emily; Shan, Jing; Yang, Guang; Calderon-Colon, Xiomara; Sultana, Shabana; Lu, Jianping; Zhou, Otto; Spronk, Derrek; Sprenger, Frank; Zhang, Yiheng; Kennedy, Don; Farbizio, Tom; Jing, Zhenxue
2012-04-01
The purpose of this study is to investigate the feasibility of increasing the system spatial resolution and scanning speed of Hologic Selenia Dimensions digital breast tomosynthesis (DBT) scanner by replacing the rotating mammography x-ray tube with a specially designed carbon nanotube (CNT) x-ray source array, which generates all the projection images needed for tomosynthesis reconstruction by electronically activating individual x-ray sources without any mechanical motion. The stationary digital breast tomosynthesis (s-DBT) design aims to (i) increase the system spatial resolution by eliminating image blurring due to x-ray tube motion and (ii) reduce the scanning time. Low spatial resolution and long scanning time are the two main technical limitations of current DBT technology. A CNT x-ray source array was designed and evaluated against a set of targeted system performance parameters. Simulations were performed to determine the maximum anode heat load at the desired focal spot size and to design the electron focusing optics. Field emission current from CNT cathode was measured for an extended period of time to determine the stable life time of CNT cathode for an expected clinical operation scenario. The source array was manufactured, tested, and integrated with a Selenia scanner. An electronic control unit was developed to interface the source array with the detection system and to scan and regulate x-ray beams. The performance of the s-DBT system was evaluated using physical phantoms. The spatially distributed CNT x-ray source array comprised 31 individually addressable x-ray sources covering a 30 angular span with 1 pitch and an isotropic focal spot size of 0.6 mm at full width at half-maximum. Stable operation at 28 kV(peak) anode voltage and 38 mA tube current was demonstrated with extended lifetime and good source-to-source consistency. For the standard imaging protocol of 15 views over 14, 100 mAs dose, and 2 × 2 detector binning, the projection resolution along the scanning direction increased from 4.0 cycles/mm [at 10% modulation-transfer-function (MTF)] in DBT to 5.1 cycles/mm in s-DBT at magnification factor of 1.08. The improvement is more pronounced for faster scanning speeds, wider angular coverage, and smaller detector pixel sizes. The scanning speed depends on the detector, the number of views, and the imaging dose. With 240 ms detector readout time, the s-DBT system scanning time is 6.3 s for a 15-view, 100 mAs scan regardless of the angular coverage. The scanning speed can be reduced to less than 4 s when detectors become faster. Initial phantom studies showed good quality reconstructed images. A prototype s-DBT scanner has been developed and evaluated by retrofitting the Selenia rotating gantry DBT scanner with a spatially distributed CNT x-ray source array. Preliminary results show that it improves system spatial resolution substantially by eliminating image blur due to x-ray focal spot motion. The scanner speed of s-DBT system is independent of angular coverage and can be increased with faster detector without image degration. The accelerated lifetime measurement demonstrated the long term stability of CNT x-ray source array with typical clinical operation lifetime over 3 years.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Becker, W.; Stalcup, T.; Schild, V.
1992-01-01
The Neil Simpson Unit is a 220,000 lb/hr pulverized coal boiler that was designed to fire a local Wyoming subbituminous coal. During the late 1980s, the Wyoming Department of Air Quality imposed emission limits on the Black Hills Power and Light Co., Neil Simpson Station. The new limits required Black Hills power to control not only particulate and sulfur dioxide (SO{sub 2}) emissions, but also nitrogen oxide (NO{sub x}) emissions. At the same time, Black Hills Power initiated an efficiency improvement study at Neil Simpson Station to investigate methods for reducing net electrical generation costs. This paper addresses the plantmore » efficiency and emissions studies, startup activities, the operating problems and successful operating solutions for NO{sub x} control when firing a Wyoming subbituminous coal. Also included is a summary of the post-0retrofit boiler performance data.« less
NASA Technical Reports Server (NTRS)
Paik, Ho J.; Canavan, Edgar R.; Kong, Qin; Moody, M. V.
1992-01-01
The paper describes the superconducting gravity gradiometers (SGGs) and superconducting accelerometers being developed at the University of Maryland, which take advantage of many exotic properties of superconductivity to obtain the required low noise, high stability, and large dynamic range. Results of laboratory demonstrations of some of these instruments are presented together with the design and operating principles. Particular attention is given to the three-axis Model II SGG and a six-axis superconducting accelerometer model (Model I SSA). Model II SGG, after a residual common-mode balance, exhibited a noise level of 0.05/sq rt Hz above 0.1 Hz and a 1/f-squared noise below 0.1 Hz. All six channels of Model I SSA operated simultaneously with linear and angular acceleration noise levels of 3 x 10 exp -10 g(E)/sq rt Hz and 5 x 10 exp -8 rad/sec per sec per sq rt Hz, respectively.
An Improved X-Band Maser System for Deep Space Network Applications
NASA Astrophysics Data System (ADS)
Britcliffe, M.; Hanson, T.; Fernandez, J.
2000-01-01
An 8450-MHz (X-band) maser system utilizing a commercial Gifford--McMahon (GM) closed-cycle cryocooler (CCR) was designed, fabricated, and demonstrated. The CCR system was used to cool a maser operating at 8450 MHz. The prototype GM CCR system meets or exceeds all Deep Space Network requirements for maser performance. The two-stage GM CCR operates at 4.2 K; for comparison, the DSN's current three-stage cryocooler, which uses a Joule--Thompson cooling stage in addition to GM cooling, operates at 4.5 K. The new CCR withstands heat loads of 1.5 W at 4.2 K as compared to 1 W at 4.5 K for the existing DSN cryocooler used for cooling masers. The measured noise temperature, T_e, of the maser used for these tests is defined at the ambient connection to the antenna feed system. The T_e measured 5.0 K at a CCR temperature of 4.5 K, about 1.5 K higher than the noise temperature of a typical DSN Block II-A X-band traveling-wave maser (TWM). Reducing the temperature of the CCR significantly lowers the maser noise temperature and increases maser gain and bandwidth. The new GM CCR gives future maser systems significant operational advantages, including reduced maintenance time and logistics requirements. The results of a demonstration of this new system are presented. Advantages of using a GM-cooled maser and the effects of the reduced CCR temperature on maser performance are discussed.
40 CFR 63.4151 - How do I demonstrate initial compliance with the emission limitations?
Code of Federal Regulations, 2010 CFR
2010-07-01
... without add-on controls option for any individual coating operation, for any group of coating operations in the affected source, or for all of the coating operations in the affected source. You must use... operation(s) in the affected source for which you do not use this option. To demonstrate initial compliance...
Wee, Young-Jung; Yun, Jong-Sun; Kang, Kui-Hyun; Ryu, Hwa-Won
2002-01-01
Enterococcus faecalis RKY1, a fumarate-reducing bacterium, was immobilized in an asymmetric hollow-fiber bioreactor (HFBR) for the continuous production of succinic acid. The cells were inoculated into the shell side of the HFBR, which was operated in transverse mode. Since the pH values in the HFBR declined during continuous operation to about 5.7, it was necessary to change the feed pH from 7.0 to 8.0 after 24 h of operation in order to enhance production of succinic acid. During continuous operation with a medium containing fumarate and glycerol, the productivity of succinate was 3.0-10.9 g/(L x h) with an initial concentration of 30 g/L of fumarate, 4.9-14.9 g/(L x h) with 50 g/L of fumarate, and 7.2-17.1 g/(L x h) with 80 g/L of fumarate for dilution rates between 0.1 and 0.4 h(-1). The maximum productivity of succinate obtained by the HFBR (17.1 g of succinate/[L x h]) was 1.7 times higher than that of the batch bioconversions (9.9 g of succinate/ [L x h]) with 80 g/L of fumarate. Furthermore, the long-term stability of the HFBR was demonstrated with a continuously efficient production of succinate for more than 15 d (360 h).
29 CFR 1926.406 - Specific purpose equipment and installations.
Code of Federal Regulations, 2011 CFR
2011-07-01
... disconnecting means shall not be less than the supply conductor ampacity. (d) X-Ray equipment—(1) Disconnecting... means shall be operable from a location readily accessible from the X-ray control. For equipment... provide equivalent access. (4) Grounding. All exposed metal parts of cranes, monorail hoists, hoists and...
29 CFR 1926.406 - Specific purpose equipment and installations.
Code of Federal Regulations, 2010 CFR
2010-07-01
... disconnecting means shall not be less than the supply conductor ampacity. (d) X-Ray equipment—(1) Disconnecting... means shall be operable from a location readily accessible from the X-ray control. For equipment... provide equivalent access. (4) Grounding. All exposed metal parts of cranes, monorail hoists, hoists and...
The Iodine Satellite (iSat) Propellant Feed System - Design and Demonstration
NASA Technical Reports Server (NTRS)
Polzin, Kurt A.; Seixal, Joao F.; Mauro, Stephanie; Burt, Adam O.; Martinez, Armando; Peeples, Steven R.
2017-01-01
CUBESATS are relatively new spacecraft platforms that are typically deployed from a launch vehicle as a secondary payload, providing low-cost access to space for a wide range of end-users. These satellites are comprised of building blocks having dimensions of 10x10x10 cm3 and a mass of 1.33 kg (a 1-U size). While providing low-cost access to space, a major operational limitation is the lack of a propulsion system that can fit within a CubeSat and is capable of executing high Delta V maneuvers. This makes it difficult to use CubeSats on missions requiring certain types of maneuvers (i.e. formation flying, spacecraft rendezvous). Work has been performed investigating the use of iodine as a propellant for Hall-effect thrusters (HETs) that could subsequently be used to provide a high specific impulse path to CubeSat propulsion. One of the systems under development to support such a technology is the propellant feed system, which must be capable of storing solid iodine propellant, applying heat to sublime the stored solid into the vapor phase, and then control the flow of low-pressure gaseous iodine to both the thruster and cathode. In a test conducted in 2016, a first-generation iodine propellant feed system was integrated with a cathode and Hall thruster. While this test had to be terminated, the feed system in this first test was able to support both cathode and integrated cathode and thruster operation prior to the termination of the test. In the present paper, we describe work performed since that initial integrated test. The effort uses lessons learned from the previous integrated test, retiring risk associated with the iodine propellant feed system, answering open design-space questions, and demonstrating iodine flow control in an integrated system. The work is undertaken at both the component level and then at the integrated subsystem level to systematically improve the feed system design, improving the hardware fidelity so the appearance and operation of the system are as flight-like as possible. At the component level, the work focuses on the propellant tank, the feed system tubing, the valves used to control the flow to the cathode and thruster, and the heaters that maintain the temperature of the flowpaths and keep iodine from redepositing and clogging the system. Work on the propellant reservoir focuses on fabricating a tank that matches the geometry of the flight design, which allows for the identification of flight tank fabrication issues that may arise and permits thermal testing of a tank possessing the same size and thermal mass as the flight design, which can be used to anchor thermal modeling of the component. This is critical for finalizing the tank heater power requirements that feed into the heater design. All metallic materials in the feed system are hastelloy or Inconel, as these materials are resistant to chemical attack by the highly-reactive iodine vapor. The tubing in the iodine feed system must possess ports to permit a neutral gas purge of the system that clear impurities after iodine is loaded into the propellant tank. A procedure is discussed whereby these ports are crimped and sealed after the purge process is completed so as to not re-expose the iodine system to air. The valves are a critical component for control of the flow to the thruster and the cathode. Significant effort has gone into upgrading the materials of the valves to make them more resistant to chemical attack and into developing an understanding of the use of these valves during the startup and operation of the cathode and thruster. The heaters that line the entire feed system are designed to draw minimal power from the power processing unit (PPU) while still having the capacity to maintain all the feed system components at the temperatures required to discourage iodine deposition inside components downstream of the propellant tank exit. The heaters possess two separate resistive traces, giving the design redundancy should a failure occur in the primary heater circuit of one of the heater zones. The task of operating a feed system in conjunction with a thruster and cathode is undertaken in a series of sub-steps. The system is first assembled and operated on xenon gas, using the valves for cathode startup and thruster control based on measurement of the discharge current. After startup and control on xenon are demonstrated, the thruster will be transitioned to iodine operation, demonstrating thruster startup and feed system control while using a xenon-fed cathode. Finally, the last step is to integrate an iodine-compatible cathode with the system, demonstrate autonomous cathode start-up with open-loop control and thruster start-up with closed-loop control for multiple cycles.
RF Phase Stability and Electron Beam Characterization for the PLEIADES Thomson X-Ray Source
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brown, W J; Hartemann, F V; Tremaine, A M
2002-10-16
We report on the performance of an S-band RF photocathode electron gun and accelerator for operation with the PLEIADES Thomson x-ray source at LLNL. To produce picosecond, high brightness x-ray pulses, picosecond timing, terahertz bandwidth diagnostics, and RF phase control are required. Planned optical, RF, x-ray and electron beam measurements to characterize the dependence of electron beam parameters and synchronization on RF phase stability are presented.
Dennis E. Ferguson; John C. Byrne; William R. Wykoff; Brian Kummet; Ted Hensold
2011-01-01
Stands of dense, natural ponderosa pine (Pinus ponderosa var. ponderosa) regeneration were operationally, precommercially thinned at seven sites - four on Nez Perce Tribal lands in northern Idaho and three on Spokane Tribal lands in eastern Washington. Five spacing treatments were studied - control (no thinning), 5x5 ft, 7x7 ft, 10x10 ft, and 14x14 ft. Sample trees...
[Plasma metabonomics study of ischemic cerebral apoplexy rats treated with Tongsaimai pellets].
Tu, Jiayu; A, Jiye; Wang, Guangji; Wen, Hongmei; Wang, Aiyun; Di, Liuqing; Cao, Bei; Liu, Linsheng
2012-04-01
To observe abnormal metabolic changes caused by ischemic cerebral apoplexy and the regulating action of Tongsaimai pellets on abnormal metabolism by analyzing the change of small molecules in plasma of ischemic cerebral apoplexy rat. To find the potential biomarkers, and to explore metabolic mechanisms of Tongsaimai pellets. Rat models of middle cerebral artery occlusion was established with electric coagulation, and rats were divided into 4 groups, model group, sham-operation group, Tongsaimai pellets group and positive control group. Tongsaimai pellets and positive control group were orally administrated by 13.2 g x kg(-1) x d(-1) of crude drugs and 32 mg x kg(-1) x d(-1) of Nimodipine respectively, m odel and sham-operation group by equal volume of distilled water for a week. Plasma of model and sham-operation group were collected, and plasma of Tongsaimai pellets and positive control group were collected on the 1st, 3rd , 7th day after administration. Endogenous metabolites of four groups were determined with GC-MS. Partial least squares discriminant analysis (PLS-DA) was applied to analyze multivariate data and set up model, and T-test was used in significant statistical analysis. Compared with sham-operation group rats, pyruvic acid, taurine and hydroxyproline obviously increased in model group rats, while lactic acid, glyceric acid, aminomalonic acid, fructose, tryptophan and leucine significantly decreased, so these metabolites were potential metabolic biomarkers. These endogenous metabolites except taurine got restoration in Tongsaimai group rats. Abnormal metabolite level in plasma can be certainly recovered by Tongsaimai pellets, and the treatment of Tongsaimai pellets can be connected with the regulation of related metabolic pathways.
Relativistic plasma control for single attosecond x-ray burst generation
NASA Astrophysics Data System (ADS)
Baeva, T.; Gordienko, S.; Pukhov, A.
2006-12-01
We show that managing time-dependent polarization of the relativistically intense laser pulse incident on a plasma surface allows us to gate a single (sub)attosecond x-ray burst even when a multicycle driver is used. The single x-ray burst is emitted when the tangential component of the vector potential at the plasma surface vanishes. This relativistic plasma control is based on the theory of relativistic spikes [T. Baeva, S. Gordienko, and A. Pukhov, Phys. Rev. E 74, 046404 (2006)]. The relativistic plasma control is demonstrated here numerically by particle-in-cell simulations.
X-29A flight control system performance during flight test
NASA Technical Reports Server (NTRS)
Chin, J.; Chacon, V.; Gera, J.
1987-01-01
An account is given of flight control system performance results for the X-29A forward-swept wing 'Advanced Technology Demonstrator' fighter aircraft, with attention to its software and hardware components' achievement of the requisite levels of system stability and desirable aircraft handling qualities. The Automatic Camber Control Logic is found to be well integrated with the stability loop of the aircraft. A number of flight test support software programs developed by NASA facilitated monitoring of the X-29A's stability in real time, and allowed the test team to clear the envelope with confidence.
Photodynamic synchrotron x-ray therapy in Glioma cell using superparamagnetic iron nanoparticle
NASA Astrophysics Data System (ADS)
Kim, Hong-Tae; Kim, Ki-Hong; Choi, Gi-Hwan; Jheon, Sanghoon; Park, Sung-Hwan; Kim, Bong-Il; Hyodo, Kazuyuki; Ando, Masami; Kim, Jong-Ki
2009-06-01
In order to evaluate cytotoxic effects of secondary Auger electron emission(Photon Activation Therapy:PAT) from alginate-coated iron nanoparticles(Alg-SNP), Alg-SNP-uptaken C6 glioma cell lines were irradiated with 6.89/7.2 Kev synchrotron X-ray. 0-125 Gy were irradiated on three experimental groups including No-SNP group incubating without SNP as control group, 6hr-SNP group incubating with SNP for 6hr and ON-SNP group incubating with SNP overnight. Irradiated cells were stained with Acridine Orange(AO) and Edithium Bromide(EB) to count their viability with fluorescent microscopy in comparison with control groups. AO stained in damaged DNA, giving FL color change in X-ray plus SNP group. EB did not or less enter inside the cell nucleus of control group. In contrast, EB entered inside the cell nucleus of Alg-SNP group which means more damage compared with Control groups. The results of MTT assay demonstrated a X-ray dose-dependent reduction generally in cell viability in the experimental groups. 3 or 9 times increase in cell survival loss rate was observed at 6hr-SNP and ON-SNP groups, respectively compared to No-SNP control group in first experiment that was done to test cell survival rate at relatively lower dose, from 0 to 50 Gy. In second experiment X-ray dose was increased to 125 Gy. Survival loss was sharply decreased in a relatively lower dose from 5 to 25 Gy, and then demonstrated an exponentially decreasing behavior with a convergence until 125 Gy for each group. This observation suggests PAT effects on the cell directly by X-ray in the presence of Alg-SNP occurs within lower X-ray dose, and conventional X-ray radiation effect becomes dominant in higher X-ray dose. The cell viability loss of ON-SNP group was three times higher compared with that of 6hr-SNP group. In conclusion, it is possible to design photodynamic X-ray therapy study using a monochromatic x-ray energy and metal nanoparticle as x-ray sensitizer, which may enable new X-ray PDT to disseminated tumors without side effects to normal surrounding tissue.
Fast, optically controlled Kerr phase shifter for digital signal processing.
Li, R B; Deng, L; Hagley, E W; Payne, M G; Bienfang, J C; Levine, Z H
2013-05-01
We demonstrate an optically controlled Kerr phase shifter using a room-temperature 85Rb vapor operating in a Raman gain scheme. Phase shifts from zero to π relative to an unshifted reference wave are observed, and gated operations are demonstrated. We further demonstrate the versatile digital manipulation of encoded signal light with an encoded phase-control light field using an unbalanced Mach-Zehnder interferometer. Generalizations of this scheme should be capable of full manipulation of a digitized signal field at high speed, opening the door to future applications.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Franklin, M.L.; Kittelson, D.B.; Leuer, R.H.
1996-10-01
A two-dimensional optimization process, which simultaneously adjusts the spark timing and equivalence ratio of a lean-burn, natural gas, Hercules G1600 engine, has been demonstrated. First, the three-dimensional surface of thermal efficiency was mapped versus spark timing and equivalence ratio at a single speed and load combination. Then the ability of the control system to find and hold the combination of timing and equivalence ratio that gives the highest thermal efficiency was explored. NO{sub x}, CO, and HC maps were also constructed from the experimental data to determine the tradeoffs between efficiency and emissions. The optimization process adds small synchronous disturbancesmore » to the spark timing and air flow while the fuel injected per cycle is held constant for four cycles. The engine speed response to these disturbances is used to determine the corrections for spark timing and equivalence ratio. The control process, in effect, uses the engine itself as the primary sensor. The control system can adapt to changes in fuel composition, operating conditions, engine wear, or other factors that may not be easily measured. Although this strategy was previously demonstrated in a Volkswagen 1.7 liter light duty engine (Frankling et al., 1994b), until now it has not been demonstrated in a heavy-duty engine. This paper covers the application of the approach to a Hercules G1600 engine.« less
High-performance large-area AMLCD avionic display module
NASA Astrophysics Data System (ADS)
Syroid, Daniel D.; Hansen, Glenn A.
1995-06-01
There is a need for a reliable source of high performance large area sunlight readable active matrix liquid crystal displays (AMLCDs) for avionic and military land vehicle applications. Image Quest has developed an avionic display module (ADM) to demonstrate the capability to produce high performance avionic displays to satisfy this need. The ADM is a large area (6.24 X 8.32 inch) display with VGA compatible interface, 640 X 480 color pixels and 64 gray shades per primary color. The display features excellent color discrimination in full sunlight due to a saturated color gamut, very low specular reflectance (< 1%) and high output white luminance (200 fL). The ADM is designed from the glass up to fully meet the avionic and military application and environment. Control over all the display performance parameters including contrast, transmission, chroma, resolution, active size and packaging configuration is ensured because Image Quest produces all of the critical elements of the display. These elements include the a-Si TFT AMLCD glass, RGB color filter matrix, bonding of folded back driver TABs, anti-reflective cover glass, LC heater and integration of high luminance hot cathode backlight with thermal controls. The display features rugged compact packaging, 2000:1 luminance dimming range and wide operating temperature range (-40 to +71 $DRGC). In the immediate future Image Quest plans to expand the development efforts to other similar custom high resolution and high performance avionic display module configurations including 4 X 4 inch delta triad, 6.7 X 6.7 inch delta triad and 16.5 inch diagonal with 1280 X 1024 pixels. Image Quest can deliver up to 10,000 displays per year on a timely basis at a reasonable cost.
Fast Fuzzy Arithmetic Operations
NASA Technical Reports Server (NTRS)
Hampton, Michael; Kosheleva, Olga
1997-01-01
In engineering applications of fuzzy logic, the main goal is not to simulate the way the experts really think, but to come up with a good engineering solution that would (ideally) be better than the expert's control, In such applications, it makes perfect sense to restrict ourselves to simplified approximate expressions for membership functions. If we need to perform arithmetic operations with the resulting fuzzy numbers, then we can use simple and fast algorithms that are known for operations with simple membership functions. In other applications, especially the ones that are related to humanities, simulating experts is one of the main goals. In such applications, we must use membership functions that capture every nuance of the expert's opinion; these functions are therefore complicated, and fuzzy arithmetic operations with the corresponding fuzzy numbers become a computational problem. In this paper, we design a new algorithm for performing such operations. This algorithm is applicable in the case when negative logarithms - log(u(x)) of membership functions u(x) are convex, and reduces computation time from O(n(exp 2))to O(n log(n)) (where n is the number of points x at which we know the membership functions u(x)).
PFM2: a 32 × 32 processor for X-ray diffraction imaging at FELs
NASA Astrophysics Data System (ADS)
Manghisoni, M.; Fabris, L.; Re, V.; Traversi, G.; Ratti, L.; Grassi, M.; Lodola, L.; Malcovati, P.; Vacchi, C.; Pancheri, L.; Benkechcache, M. E. A.; Dalla Betta, G.-F.; Xu, H.; Verzellesi, G.; Ronchin, S.; Boscardin, M.; Batignani, G.; Bettarini, S.; Casarosa, G.; Forti, F.; Giorgi, M.; Paladino, A.; Paoloni, E.; Rizzo, G.; Morsani, F.
2016-11-01
This work is concerned with the design of a readout chip for application to experiments at the next generation X-ray Free Electron Lasers (FEL). The ASIC, named PixFEL Matrix (PFM2), has been designed in a 65 nm CMOS technology and consists of 32 × 32 pixels. Each cell covers an area of 110 × 110 μm2 and includes a low-noise charge sensitive amplifier (CSA) with dynamic signal compression, a time-variant shaper used to process the preamplifier output signal, a 10-bit successive approximation register (SAR) analog-to-digital converter (ADC) and digital circuitry for channel control and data readout. Two different solutions for the readout channel, based on different versions of the time-variant filter, have been integrated in the chip. Both solutions can be operated in such a way to cope with the high frame rate (exceeding 1 MHz) foreseen for future X-ray FEL machines. The ASIC will be bump bonded to a slim/active edge pixel sensor to form the first demonstrator for the PixFEL X-ray imager. This work has been carried out in the frame of the PixFEL project funded by Istituto Nazionale di Fisica Nucleare (INFN), Italy.
Grain engineering: How nanoscale inhomogeneities can control charge collection in solar cells
DOE Office of Scientific and Technical Information (OSTI.GOV)
West, Bradley M.; Stuckelberger, Michael; Guthrey, Harvey
Statistical and correlative analysis are increasingly important in the design and study of new materials, from semiconductors to metals. Non-destructive measurement techniques, with high spatial resolution, capable of correlating composition and/or structure with device properties, are few and far between. For the case of polycrystalline and inhomogeneous materials, the added challenge is that nanoscale resolution is in general not compatible with the large sampling areas necessary to have a statistical representation of the specimen under study. For the study of grain cores and grain boundaries in polycrystalline solar absorbers this is of particular importance since their dissimilar behavior and variabilitymore » throughout the samples makes it difficult to draw conclusions and ultimately optimize the material. In this study, we present a nanoscale in-operando approach based on the multimodal utilization of synchrotron nano x-ray fluorescence and x-ray beam induced current collected for grain core and grain boundary areas and correlated pixel-by-pixel in fully operational Cu(In(1-x)Gax)Se2Cu(In(1-x)Gax)Se2 solar cells. We observe that low gallium cells have grain boundaries that over perform compared to the grain cores and high gallium cells have boundaries that under perform. These results demonstrate how nanoscale correlative X-ray microscopy can guide research pathways towards grain engineering low cost, high efficiency solar cells.« less
Grain engineering: How nanoscale inhomogeneities can control charge collection in solar cells
West, Bradley M.; Stuckelberger, Michael; Guthrey, Harvey; ...
2016-12-16
We present that statistical and correlative analysis are increasingly important in the design and study of new materials, from semiconductors to metals. Non-destructive measurement techniques, with high spatial resolution, capable of correlating composition and/or structure with device properties, are few and far between. For the case of polycrystalline and inhomogeneous materials, the added challenge is that nanoscale resolution is in general not compatible with the large sampling areas necessary to have a statistical representation of the specimen under study. For the study of grain cores and grain boundaries in polycrystalline solar absorbers this is of particular importance since their dissimilarmore » behavior and variability throughout the samples makes it difficult to draw conclusions and ultimately optimize the material. In this study, we present a nanoscale in-operando approach based on the multimodal utilization of synchrotron nano x-ray fluorescence and x-ray beam induced current collected for grain core and grain boundary areas and correlated pixel-by-pixel in fully operational Cu(In (1-x)Ga x)Se 2 solar cells. We observe that low gallium cells have grain boundaries that over perform compared to the grain cores and high gallium cells have boundaries that under perform. In conclusion, these results demonstrate how nanoscale correlative X-ray microscopy can guide research pathways towards grain engineering low cost, high efficiency solar cells.« less
Quantum-well-base heterojunction bipolar light-emitting transistor
NASA Astrophysics Data System (ADS)
Feng, M.; Holonyak, N.; Chan, R.
2004-03-01
This letter reports the enhanced radiative recombination realized by incorporating InGaAs quantum wells in the base layer of light-emitting InGaP/GaAs heterojunction bipolar transistors (LETs) operating in the common-emitter configuration. Two 50 Å In1-xGaxAs (x=85%) quantum wells (QWs) acting, in effect, as electron capture centers ("traps") are imbedded in the 300 Å GaAs base layer, thus improving (as a "collector" and recombination center) the light emission intensity compared to a similar LET structure without QWs in the base. Gigahertz operation of the QW LET with simultaneously amplified electrical output and an optical output with signal modulation is demonstrated.
Results of prototype software development for automation of shuttle proximity operations
NASA Technical Reports Server (NTRS)
Hiers, Hal; Olszweski, Oscar
1991-01-01
The effort involves demonstration of expert system technology application to Shuttle rendezvous operations in a high-fidelity, real-time simulation environment. The JSC Systems Engineering Simulator (SES) served as the test bed for the demonstration. Rendezvous applications were focused on crew procedures and monitoring of sensor health and trajectory status. Proximity operations applications were focused on monitoring, crew advisory, and control of the approach trajectory. Guidance, Navigation, and Control areas of emphasis included the approach, transition and stationkeeping guidance, and laser docking sensor navigation. Operator interface displays for monitor and control functions were developed. A rule-based expert system was developed to manage the relative navigation system/sensors for nominal operations and simple failure contingencies. Testing resulted in the following findings; (1) the developed guidance is applicable for operations with LVLH stabilized targets; (2) closing rates less than 0.05 feet per second are difficult to maintain due to the Shuttle translational/rotational cross-coupling; (3) automated operations result in reduced propellant consumption and plume impingement effects on the target as compared to manual operations; and (4) braking gates are beneficial for trajectory management. A versatile guidance design was demonstrated. An accurate proximity operations sensor/navigation system to provide relative attitude information within 30 feet is required and redesign of the existing Shuttle digital autopilot should be considered to reduce the cross-coupling effects. This activity has demonstrated the feasibility of automated Shuttle proximity operations with the Space Station Freedom. Indications are that berthing operations as well as docking can be supported.
Status of the Superconducting Insertion Device Control at TLS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hu, K. H.; Wang, C. J.; Lee, Demi
2007-01-19
Superconducting insertion devices are installed at Taiwan Light Source to meet the rapidly growing demand of X-ray users. A control system supports the operation of all these superconducting insertion devices. Control system coordinates the operation of the main power supply and the trimming power supply to charge/discharge the magnet and provide essential interlock protection for the coils and vacuum ducts. Quench protection and various cryogenic interlocks are designed to prevent damage to the magnet. A friendly user interface supports routine operation. Various applications are also developed to aid the operation of these insertion devices. Design consideration and details of themore » implementation will be summarized in this report.« less
A COTS-Based Replacement Strategy for Aging Avionics Computers
2001-12-01
Communication Control Unit. A COTS-Based Replacement Strategy for Aging Avionics Computers COTS Microprocessor Real Time Operating System New Native Code...Native Code Objec ts Native Code Thread Real - Time Operating System Legacy Function x Virtual Component Environment Context Switch Thunk Add-in Replace
SU(3)_C× SU(2)_L× U(1)_Y( × U(1)_X ) as a symmetry of division algebraic ladder operators
NASA Astrophysics Data System (ADS)
Furey, C.
2018-05-01
We demonstrate a model which captures certain attractive features of SU(5) theory, while providing a possible escape from proton decay. In this paper we show how ladder operators arise from the division algebras R, C, H, and O. From the SU( n) symmetry of these ladder operators, we then demonstrate a model which has much structural similarity to Georgi and Glashow's SU(5) grand unified theory. However, in this case, the transitions leading to proton decay are expected to be blocked, given that they coincide with presumably forbidden transformations which would incorrectly mix distinct algebraic actions. As a result, we find that we are left with G_{sm} = SU(3)_C× SU(2)_L× U(1)_Y / Z_6. Finally, we point out that if U( n) ladder symmetries are used in place of SU( n), it may then be possible to find this same G_{sm}=SU(3)_C× SU(2)_L× U(1)_Y / Z_6, together with an extra U(1)_X symmetry, related to B-L.
The Alaska SAR processor - Operations and control
NASA Technical Reports Server (NTRS)
Carande, Richard E.
1989-01-01
The Alaska SAR (synthetic-aperture radar) Facility (ASF) will be capable of receiving, processing, archiving, and producing a variety of SAR image products from three satellite-borne SARs: E-ERS-1 (ESA), J-ERS-1 (NASDA) and Radarsat (Canada). Crucial to the success of the ASF is the Alaska SAR processor (ASP), which will be capable of processing over 200 100-km x 100-km (Seasat-like) frames per day from the raw SAR data, at a ground resolution of about 30 m x 30 m. The processed imagery is of high geometric and radiometric accuracy, and is geolocated to within 500 m. Special-purpose hardware has been designed to execute a SAR processing algorithm to achieve this performance. This hardware is currently undergoing acceptance testing for delivery to the University of Alaska. Particular attention has been devoted to making the operations semi-automated and to providing a friendly operator interface via a computer workstation. The operations and control of the Alaska SAR processor are described.
NASA Astrophysics Data System (ADS)
Knipe, Kevin; Manero, Albert; Siddiqui, Sanna F.; Meid, Carla; Wischek, Janine; Okasinski, John; Almer, Jonathan; Karlsson, Anette M.; Bartsch, Marion; Raghavan, Seetha
2014-07-01
The mechanical behaviour of thermal barrier coatings in operation holds the key to understanding durability of jet engine turbine blades. Here we report the results from experiments that monitor strains in the layers of a coating subjected to thermal gradients and mechanical loads representing extreme engine environments. Hollow cylindrical specimens, with electron beam physical vapour deposited coatings, were tested with internal cooling and external heating under various controlled conditions. High-energy synchrotron X-ray measurements captured the in situ strain response through the depth of each layer, revealing the link between these conditions and the evolution of local strains. Results of this study demonstrate that variations in these conditions create corresponding trends in depth-resolved strains with the largest effects displayed at or near the interface with the bond coat. With larger temperature drops across the coating, significant strain gradients are seen, which can contribute to failure modes occurring within the layer adjacent to the interface.
NASA Astrophysics Data System (ADS)
Conder, Joanna; Bouchet, Renaud; Trabesinger, Sigita; Marino, Cyril; Gubler, Lorenz; Villevieille, Claire
2017-06-01
In the on going quest towards lithium-battery chemistries beyond the lithium-ion technology, the lithium-sulfur system is emerging as one of the most promising candidates. The major outstanding challenge on the route to commercialization is controlling the so-called polysulfide shuttle, which is responsible for the poor cycling efficiency of the current generation of lithium-sulfur batteries. However, the mechanistic understanding of the reactions underlying the polysulfide shuttle is still incomplete. Here we report the direct observation of lithium polysulfides in a lithium-sulfur cell during operation by means of operando X-ray diffraction. We identify signatures of polysulfides adsorbed on the surface of a glass-fibre separator and monitor their evolution during cycling. Furthermore, we demonstrate that the adsorption of the polysulfides onto SiO2 can be harnessed for buffering the polysulfide redox shuttle. The use of fumed silica as an electrolyte additive therefore significantly improves the specific charge and Coulombic efficiency of lithium-sulfur batteries.
Memristor and selector devices fabricated from HfO2-xNx
NASA Astrophysics Data System (ADS)
Murdoch, B. J.; McCulloch, D. G.; Ganesan, R.; McKenzie, D. R.; Bilek, M. M. M.; Partridge, J. G.
2016-04-01
Monoclinic HfO2-xNx has been incorporated into two-terminal devices exhibiting either memristor or selector operation depending on the controlled inclusion/suppression of mobile oxygen vacancies. In HfO2 memristors containing oxygen vacancies, gradual conductance modulation, short-term plasticity, and long-term potentiation were observed using appropriate voltage-spike stimulation, suggesting suitability for artificial neural networks. Passivation of oxygen vacancies, confirmed by X-ray absorption spectroscopy, was achieved in HfO2-xNx films by the addition of nitrogen during growth. Selector devices formed on these films exhibited threshold switching and current controlled negative differential resistance consistent with thermally driven insulator to metal transitions.
Synergistic effects of food and predators on annual reproductive success in song sparrows.
Zanette, Liana; Smith, James N M; van Oort, Harry; Clinchy, Michael
2003-04-22
The behaviour literature is full of studies showing that animals in every taxon balance the probability of acquiring food with the risk of being preyed upon. While interactions between food and predators clearly operate at an individual scale, population-scale studies have tended to focus on only one factor at a time. Consequently, interactive (or 'synergistic') effects of food and predators on whole populations have only twice before been experimentally demonstrated in mammals. We conducted a 2 x 2 experiment to examine the joint effects of food supply and predator pressure on the annual reproductive success of song sparrows (Melospiza melodia). Our results show that these two factors do not operate in an additive way, but instead have a synergistic effect on reproduction. Relative to controls, sparrows reared 1.1 more young when food was added and 1.3 more when predator pressure was low. When these treatments were combined 4.0 extra young were produced, almost twice as many as expected from an additive model. These results are a cause for optimism for avian conservation because they demonstrate that remedial actions, aimed at simultaneously augmenting food and reducing predators, can produce dramatic increases in reproductive success.
1999-08-23
A worker takes a measurement for construction of the Reusable Launch Vehicle (RLV) complex at KSC. Located near the Shuttle Landing Facility, the complex will include facilities for related ground support equipment and administrative/ technical support. It will be available to accommodate the Space Shuttle; the X-34 RLV technology demonstrator; the L-1011 carrier aircraft for Pegasus and X-34; and other RLV and X-vehicle programs. The complex is jointly funded by the Spaceport Florida Authority, NASA's Space Shuttle Program and KSC. The facility will be operational in early 2000
1999-08-23
At the construction site of the Reusable Launch Vehicle (RLV) complex at KSC, workers take measurements for one of the buildings. Located near the Shuttle Landing Facility, the complex will include facilities for related ground support equipment and administrative/ technical support. It will be available to accommodate the Space Shuttle; the X-34 RLV technology demonstrator; the L-1011 carrier aircraft for Pegasus and X-34; and other RLV and X-vehicle programs. The complex is jointly funded by the Spaceport Florida Authority, NASA's Space Shuttle Program and KSC. The facility will be operational in early 2000
1999-10-29
The support building at the $8 million Reusable Launch Vehicle (RLV) Support Complex at Kennedy Space Center takes form. It will house related ground support equipment and administrative/technical support. The RLV complex includes a multi-purpose hangar that will be available to accommodate the Space Shuttle; the X-34 RLV technology demonstrator; the L-1011 carrier aircraft for Pegasus and X-34; and other RLV and X-vehicle programs. The complex is jointly funded by the Spaceport Florida Authority, NASA's Space Shuttle Program and KSC. The facility will be operational in early 2000
1999-08-23
At the construction site of the Reusable Launch Vehicle (RLV) complex at KSC, a worker takes a measurement. Located near the Shuttle Landing Facility, the complex will include facilities for related ground support equipment and administrative/ technical support. It will be available to accommodate the Space Shuttle; the X-34 RLV technology demonstrator; the L-1011 carrier aircraft for Pegasus and X-34; and other RLV and X-vehicle programs. The complex is jointly funded by the Spaceport Florida Authority, NASA's Space Shuttle Program and KSC. The facility will be operational in early 2000
Three-dimensional x-ray inspection of food products
NASA Astrophysics Data System (ADS)
Graves, Mark; Batchelor, Bruce G.; Palmer, Stephen C.
1994-09-01
Modern food production techniques operate at high speed and sometimes fill several containers simultaneously; individual containers never become available for inspection by conventional x- ray systems. There is a constant demand for improved methods for detecting foreign bodies, such as glass, plastic, wood, stone, animal remains, etc. These requirements lead to significant problems with existing inspection techniques, which are susceptible to noise and are unable to detect long thin contaminants reliably. Experimental results demonstrate these points. The paper proposes the use of two x-ray inspection systems, with orthogonal beams to overcome these difficulties.
Active vibration control of a full scale aircraft wing using a reconfigurable controller
NASA Astrophysics Data System (ADS)
Prakash, Shashikala; Renjith Kumar, T. G.; Raja, S.; Dwarakanathan, D.; Subramani, H.; Karthikeyan, C.
2016-01-01
This work highlights the design of a Reconfigurable Active Vibration Control (AVC) System for aircraft structures using adaptive techniques. The AVC system with a multichannel capability is realized using Filtered-X Least Mean Square algorithm (FxLMS) on Xilinx Virtex-4 Field Programmable Gate Array (FPGA) platform in Very High Speed Integrated Circuits Hardware Description Language, (VHDL). The HDL design is made based on Finite State Machine (FSM) model with Floating point Intellectual Property (IP) cores for arithmetic operations. The use of FPGA facilitates to modify the system parameters even during runtime depending on the changes in user's requirements. The locations of the control actuators are optimized based on dynamic modal strain approach using genetic algorithm (GA). The developed system has been successfully deployed for the AVC testing of the full-scale wing of an all composite two seater transport aircraft. Several closed loop configurations like single channel and multi-channel control have been tested. The experimental results from the studies presented here are very encouraging. They demonstrate the usefulness of the system's reconfigurability for real time applications.
Koppa, P; Chavel, P; Oudar, J L; Kuszelewicz, R; Schnell, J P; Pocholle, J P
1997-08-10
We present experimental results on a 1-to-64-channel free-space photonic switching demonstration system based on GaAs/GaAlAs multiple-quantum-well active device arrays. Two control schemes are demonstrated: data transparent optical self-routing usable in a packet-switching environment and direct optical control with potential signal amplification for circuit switching. The self-routing operation relies on the optical recognition of the binary destination address coded in each packet header. Address decoding is implemented with elementary optical bistable devices and modulator pixels as all-optical latches and electro-optical and gates, respectively. All 60 defect-free channels of the system could be operated one by one, but the simultaneous operation of only three channels could be achieved mainly because of the spatial nonhomogeneities of the devices. Direct-control operation is based on directly setting the bistable device reflectivity with a variable-control beam power. This working mode turned out to be much more tolerant of spatial noises: 37 channels of the system could be operated simultaneously. Further development of the system to a crossbar of N inputs and M outputs and system miniaturization are also considered.
NASA Technical Reports Server (NTRS)
Tang, M. H.; Pearson, G. P. E.
1973-01-01
Control-surface hinge-moment measurements obtained in the X-24A lifting body flight-test program are compared with results from wind-tunnel tests. The effects of variations in angle of attack, angle of sideslip, rudder bias, rudder deflection, upper-flap deflection, lower-flap deflection, Mach number, and rocket-engine operation on the control-surface hinge moments are presented. In-flight motion pictures of tufts attached to the inboard side of the right fin and the rudder and upper-flap surfaces are discussed.
40 CFR 63.5725 - What are the requirements for monitoring and demonstrating continuous compliance?
Code of Federal Regulations, 2014 CFR
2014-07-01
... Pollutants for Boat Manufacturing Demonstrating Compliance for Open Molding Operations Controlled by Add-on... successive cycles of operation to have a valid hour of data. (2) You must have valid data from at least 90... parameter monitoring system and collect emission capture system and add-on control device parameter data at...
40 CFR 63.5725 - What are the requirements for monitoring and demonstrating continuous compliance?
Code of Federal Regulations, 2013 CFR
2013-07-01
... Pollutants for Boat Manufacturing Demonstrating Compliance for Open Molding Operations Controlled by Add-on... successive cycles of operation to have a valid hour of data. (2) You must have valid data from at least 90... parameter monitoring system and collect emission capture system and add-on control device parameter data at...
Air Force Support of Army Ground Operations Lessons Learned during World War II, Korea, and Vietnam
1989-03-06
Th ;e 8epre--cdin this paper .rv thoe. of ’:ceauhor IDep 2rtmt-nt of Diefense rayo t gr: s hsPcC % FOC, O P 0- C GOUND OP!-txA’TONS ’A NS tTAI.D 11...NOTE S T edder, Wi.th Preudice: The War Memoirs . - y Air Force. Lord Tedaer. rr- 40-43. 2.".~ : X :"~ , M~.c, ’ = A r Power in Three Wars WW 7:, Kora...that FEAF assume operational control over land based Marine air units and over carri.er bjdsed aviation operating over Korea effective as soon as X
A Mobile Satellite Experiment (MSAT-X) network definition
NASA Technical Reports Server (NTRS)
Wang, Charles C.; Yan, Tsun-Yee
1990-01-01
The network architecture development of the Mobile Satellite Experiment (MSAT-X) project for the past few years is described. The results and findings of the network research activities carried out under the MSAT-X project are summarized. A framework is presented upon which the Mobile Satellite Systems (MSSs) operator can design a commercial network. A sample network configuration and its capability are also included under the projected scenario. The Communication Interconnection aspect of the MSAT-X network is discussed. In the MSAT-X network structure two basic protocols are presented: the channel access protocol, and the link connection protocol. The error-control techniques used in the MSAT-X project and the packet structure are also discussed. A description of two testbeds developed for experimentally simulating the channel access protocol and link control protocol, respectively, is presented. A sample network configuration and some future network activities of the MSAT-X project are also presented.
Dual-lasing channel quantum cascade laser based on scattering-assisted injection design.
Wen, Boyu; Xu, Chao; Wang, Siyi; Wang, Kaixi; Tam, Man Chun; Wasilewski, Zbig; Ban, Dayan
2018-04-02
A dual lasing channel Terahertz Quantum Cascade laser (THz QCL) based on GaAs/Al 0.17 Ga 0.83 As material system is demonstrated. The device shows the lowest reported threshold current density (550A/cm 2 at 50K) of GaAs/Al x Ga 1-x As material system based scattering-assisted (SA) structures and operates up to a maximum lasing temperature of 144K. Dual lasing channel operation is investigated theoretically and experimentally. The combination of low frequency emission, dual lasing channel operation, low lasing threshold current density and high temperature performance make such devices ideal candidates for low frequency applications, and initiates the design strategy for achieving high-temperature performance terahertz quantum cascade laser with wide frequency coverage at low frequency.
Highly mobile ferroelastic domain walls in compositionally graded ferroelectric thin films
Damodaran, Anoop; Okatan, M. B.; Kacher, J.; ...
2016-02-15
Domains and domain walls are critical in determining the response of ferroelectrics, and the ability to controllably create, annihilate, or move domains is essential to enable a range of next-generation devices. Whereas electric-field control has been demonstrated for ferroelectric 180° domain walls, similar control of ferroelastic domains has not been achieved. Here, using controlled composition and strain gradients, we demonstrate deterministic control of ferroelastic domains that are rendered highly mobile in a controlled and reversible manner. Through a combination of thin-film growth, transmission-electron-microscopy-based nanobeam diffraction and nanoscale band-excitation switching spectroscopy, we show that strain gradients in compositionally graded PbZr 1-xTimore » xO 3 heterostructures stabilize needle-like ferroelastic domains that terminate inside the film. These needle-like domains are highly labile in the out-of-plane direction under applied electric fields, producing a locally enhanced piezoresponse. This work demonstrates the efficacy of novel modes of epitaxy in providing new modalities of domain engineering and potential for as-yet-unrealized nanoscale functional devices.« less
Highly mobile ferroelastic domain walls in compositionally graded ferroelectric thin films
DOE Office of Scientific and Technical Information (OSTI.GOV)
Damodaran, Anoop; Okatan, M. B.; Kacher, J.
Domains and domain walls are critical in determining the response of ferroelectrics, and the ability to controllably create, annihilate, or move domains is essential to enable a range of next-generation devices. Whereas electric-field control has been demonstrated for ferroelectric 180° domain walls, similar control of ferroelastic domains has not been achieved. Here, using controlled composition and strain gradients, we demonstrate deterministic control of ferroelastic domains that are rendered highly mobile in a controlled and reversible manner. Through a combination of thin-film growth, transmission-electron-microscopy-based nanobeam diffraction and nanoscale band-excitation switching spectroscopy, we show that strain gradients in compositionally graded PbZr 1-xTimore » xO 3 heterostructures stabilize needle-like ferroelastic domains that terminate inside the film. These needle-like domains are highly labile in the out-of-plane direction under applied electric fields, producing a locally enhanced piezoresponse. This work demonstrates the efficacy of novel modes of epitaxy in providing new modalities of domain engineering and potential for as-yet-unrealized nanoscale functional devices.« less
Multiple-degree-of-freedom vehicle
Borenstein, Johann
1995-01-01
A multi-degree-of-freedom vehicle employs a compliant linkage to accommodate the need for a variation in the distance between drive wheels or drive systems which are independently steerable and drivable. The subject vehicle is provided with rotary encodes to provide signals representative of the orientation of the steering pivot associated with each such drive wheel or system, and a linear encoder which issues a signal representative of the fluctuations in the distance between the drive elements. The wheels of the vehicle are steered and driven in response to the linear encoder signal, there being provided a controller system for minimizing the fluctuations in the distance. The controller system is a software implementation of a plurality of controllers, operating at the chassis level and at the vehicle level. A trajectory interpolator receives x-displacement, y-displacement, and .theta.-displacement signals and produces to the vehicle level controller trajectory signals corresponding to interpolated control signals. The x-displacement, y-displacement, and .theta.-displacement signals are received from a human operator, via a manipulable joy stick.
Ultrafast X-Ray Coherent Control
DOE Office of Scientific and Technical Information (OSTI.GOV)
Reis, David
2009-05-01
This main purpose of this grant was to develop the nascent eld of ultrafast x-ray science using accelerator-based sources, and originally developed from an idea that a laser could modulate the di racting properties of a x-ray di racting crystal on a fast enough time scale to switch out in time a shorter slice from the already short x-ray pulses from a synchrotron. The research was carried out primarily at the Advanced Photon Source (APS) sector 7 at Argonne National Laboratory and the Sub-Picosecond Pulse Source (SPPS) at SLAC; in anticipation of the Linac Coherent Light Source (LCLS) x-ray freemore » electron laser that became operational in 2009 at SLAC (all National User Facilities operated by BES). The research centered on the generation, control and measurement of atomic-scale dynamics in atomic, molecular optical and condensed matter systems with temporal and spatial resolution . It helped develop the ultrafast physics, techniques and scienti c case for using the unprecedented characteristics of the LCLS. The project has been very successful with results have been disseminated widely and in top journals, have been well cited in the eld, and have laid the foundation for many experiments being performed on the LCLS, the world's rst hard x-ray free electron laser.« less
Design Description of the X-33 Avionics Architecture
NASA Technical Reports Server (NTRS)
Reichenfeld, Curtis J.; Jones, Paul G.
1999-01-01
In this paper, we provide a design description of the X-33 avionics architecture. The X-33 is an autonomous Single Stage to Orbit (SSTO) launch vehicle currently being developed by Lockheed Martin for NASA as a technology demonstrator for the VentureStar Reusable Launch Vehicle (RLV). The X-33 avionics provides autonomous control of die vehicle throughout takeoff, ascent, descent, approach, landing, rollout, and vehicle safing. During flight the avionics provides communication to the range through uplinked commands and downlinked telemetry. During pre-launch and post-safing activities, the avionics provides interfaces to ground support consoles that perform vehicle flight preparations and maintenance. The X-33 Avionics is a hybrid of centralized and distributed processing elements connected by three dual redundant Mil-Std 1553 data buses. These data buses are controlled by a central processing suite located in the avionics bay and composed of triplex redundant Vehicle Mission Computers (VMCs). The VMCs integrate mission management, guidance, navigation, flight control, subsystem control and redundancy management functions. The vehicle sensors, effectors and subsystems are interfaced directly to the centralized VMCs as remote terminals or through dual redundant Data Interface Units (DIUs). The DIUs are located forward and aft of the avionics bay and provide signal conditioning, health monitoring, low level subsystem control and data interface functions. Each VMC is connected to all three redundant 1553 data buses for monitoring and provides a complete identical data set to the processing algorithms. This enables bus faults to be detected and reconfigured through a voted bus control configuration. Data is also shared between VMCs though a cross channel data link that is implemented in hardware and controlled by AlliedSignal's Fault Tolerant Executive (FTE). The FTE synchronizes processors within the VMC and synchronizes redundant VMCs to each other. The FTE provides an output-voting plane to detect, isolate and contain faults due to internal hardware or software faults and reconfigures the VMCs to accommodate these faults. Critical data in the 1553 messages are scheduled and synchronized to specific processing frames in order to minimize data latency. In order to achieve an open architecture, military and commercial off-the-shelf equipment is incorporated using common processors, standard VME backplanes and chassis, the VxWorks operating system, and MartixX for automatic code generation. The use of off-the-shelf tools and equipment helps reduce development time and enables software reuse. The open architecture allows for technology insertion, while the distributed modular elements allow for expansion to increased redundancy levels to meet the higher reliability goals of future RLVs.
NASA Astrophysics Data System (ADS)
Soppa, Uwe; Görlach, Thomas; Roenneke, Axel Justus
2002-01-01
As a solution to meet a safety requirement to the future full scale space station infrastructure, the Crew Return/Rescue Vehicle (CRV) was supposed to supply the return capability for the complete ISS crew of 7 astronauts back to earth in case of an emergency. A prototype of such a vehicle named X-38 has been developed and built by NASA with European partnership (ESA, DLR). An series of aerial demonstrators (V13x) for tests of the subsonic TAEM phase and the parafoil descent and landing system has been flown by NASA from 1998 to 2001. A full scale unmanned space flight demonstrator (V201) has been built at JSC Houston and although the project has been stopped for budgetary reasons in 2002, it will hopefully still be flown in near future. The X-38 is a lifting body with hypersonic lift to drag ratio about 0.9. In comparison to the Space Shuttle Orbiter, this design provides less aerodynamic maneuvrability and a different actuator layout (divided body flap and winglet rudders instead as combined aileron and elevon in addition to thrust- ers for the early re-entry phase). Hence, the guidance and control concepts used onboard the shuttle orbiter had to be adapted and further developed for the application on the new vehicle. In the frame of the European share of the X-38 project and also of the German TETRA (TEchnol- ogy for future space TRAnsportation) project different GNC related contributions have been made: First, the primary flight control software for the autonomous guidance and control of the X-38 para- foil descent and landing phase has been developed, integrated and successfully flown on multiple vehicles and missions during the aerial drop test campaign conducted by NASA. Second, a real time X-38 vehicle simulator was provided to NASA which has also been used for the validation of a European re-entry guidance and control software (see below). According to the NASA verification and validation plan this simulator is supposed to be used as an independent vali- dation tool for the X-38 re-entry simulation and onboard software. Third, alternate guidance and control algorithms for the re-entry flight phase of X-38, using onboard flight path optimization for the guidance task and dynamic inversion control methods for attitude control have been developed. The resulting alternate guidance and control software shall be flown as a flight experiment onboard the V201 spaceflight test vehicle. Fourth, a fault tolerant computer similar to the one used onboard the ISS is planned to be integrated into the V201 spaceflight test vehicle as a host of the re-entry GNC software mentioned above. This paper will summarize the development and test phases of European guidance and control soft- ware and avionics elements for the different phases of the X-38 mission. Flight test results from the X38 aerial drop test campaigns will be presented and discussed. In addition, the flight experiment of the fault tolerant computer will be described.
Operation and Maintenance of Clarks Hill Lake, Savannah River, Georgia, and South Carolina.
1981-10-01
gramineus Vesper Sparrow C/W X *Aimophila aestivalis Bachman’s Sparrow U/P X Junco hyemalis Slate-colored Junco C/W X X Spizella passerina Chipping...Results are analyzed to determine levels of prey and predatory fishes to aid in determining stocking rates of additional predators such as hybrid bass. e...be to have a management system controlled to some degree by the Corps of Engineers. The design could be a comprehensive wildlife management program
Robust Controller Design: A Bounded-Input-Bounded-Output Worst-Case Approach
1992-03-01
show that 2 implies 1, suppose 1 does not hold, i.e., that p(M) > 1. The Perron - Frobenius theory for nonnegative matrices states that p(M) is itself an...Pz denote the positive cones inside X, Z consisting of elements with nonnegative pointwise components. Define the operator .4 : X -* Z, decomposed...topology.) The dual cone P! again consists of the nonnegative elements in Z*. The Lagrangian can be defined as L(x,z ’) {< x,c" > + < Ax - b,z
2009-10-26
NASA Ares I-X Launch Director Ed Mango monitors the launch countdown from Firing Room One of the Launch Control Center (LCC) at the Kennedy Space Center during the planned launch of the Ares I-X rocket from pad 39b at the Kennedy Space Center in Cape Canaveral, Fla., Tuesday, Oct. 27, 2009. The flight test of Ares I-X will provide NASA with an early opportunity to test and prove flight characteristics, hardware, facilities and ground operations associated with the Ares I. Photo Credit: (NASA/Bill Ingalls)
2009-10-27
NASA Ares I-X Launch Director Ed Mango, 3rd from left, along with other mission managers watches the launch of the Ares I-X rocket from Firing Room One of the Launch Control Center (LCC) at the Kennedy Space Center in Cape Canaveral, Fla., Wednesday, Oct. 28, 2009. The flight test of Ares I-X will provide NASA with an early opportunity to test and prove flight characteristics, hardware, facilities and ground operations associated with the Ares I. Photo Credit: (NASA/Bill Ingalls)
Density gradient free electron collisionally excited X-ray laser
Campbell, Edward M.; Rosen, Mordecai D.
1989-01-01
An operational X-ray laser (30) is provided that amplifies 3p-3s transition X-ray radiation along an approximately linear path. The X-ray laser (30) is driven by a high power optical laser. The driving line focused optical laser beam (32) illuminates a free-standing thin foil (34) that may be associated with a substrate (36) for improved structural integrity. This illumination produces a generally cylindrically shaped plasma having an essentially uniform electron density and temperature, that exists over a long period of time, and provides the X-ray laser gain medium. The X-ray laser (30) may be driven by more than one optical laser beam (32, 44). The X-ray laser (30) has been successfully demonstrated to function in a series of experimental tests.
High-power, format-flexible, 885-nm vertical-cavity surface-emitting laser arrays
NASA Astrophysics Data System (ADS)
Wang, Chad; Talantov, Fedor; Garrett, Henry; Berdin, Glen; Cardellino, Terri; Millenheft, David; Geske, Jonathan
2013-03-01
High-power, format flexible, 885 nm vertical-cavity surface-emitting laser (VCSEL) arrays have been developed for solid-state pumping and illumination applications. In this approach, a common VCSEL size format was designed to enable tiling into flexible formats and operating configurations. The fabrication of a common chip size on ceramic submount enables low-cost volume manufacturing of high-power VCSEL arrays. This base VCSEL chip was designed to be 5x3.33 mm2, and produced up to 50 Watts of peak continuous wave (CW) power. To scale to higher powers, multiple chips can be tiled into a combination of series or parallel configurations tailored to the application driver conditions. In actively cooled CW operation, the VCSEL array chips were packaged onto a single water channel cooler, and we have demonstrated 0.5x1, 1x1, and 1x3 cm2 formats, producing 150, 250, and 500 Watts of peak power, respectively, in under 130 A operating current. In QCW operation, the 1x3 cm2 VCSEL module, which contains 18 VCSEL array chips packaged on a single water cooler, produced over 1.3 kW of peak power. In passively cooled packages, multiple chip configurations have been developed for illumination applications, producing over 300 Watts of peak power in QCW operating conditions. These VCSEL chips use a substrate-removed structure to allow for efficient thermal heatsinking to enable high-power operation. This scalable, format flexible VCSEL architecture can be applied to wavelengths ranging from 800 to 1100 nm, and can be used to tailor emission spectral widths and build high-power hyperspectral sources.
NASA Technical Reports Server (NTRS)
Moses, Paul L.
2003-01-01
X-43C Project is a hypersonic flight demonstration being executed as a collaboration between the National Aeronautics and Space Administration (NASA) and the United States Air Force (USAF). X-43C will expand the hypersonic flight envelope for air breathing engines beyond the history making efforts of the Hyper-X Program (X-43A). X-43C will demonstrate sustained accelerating flight during three flight tests of expendable X-43C Demonstrator Vehicles (DVs). The approximately 16-foot long X-43C DV will be boosted to the starting test conditions, separate from the booster, and accelerate from Mach 5 to Mach 7 under its own power and autonomous control. The DVs are to be powered by a liquid hydrocarbon-fueled, fuel-cooled, dual-mode, airframe integrated scramjet engine system developed under the USAF HyTech Program. The Project is managed by NASA Langley Research Center as part of NASA s Next Generation Launch Technology Program. Flight tests will be conducted by NASA Dryden Flight Research Center over water off the coast of California in the Pacific Test Range. The NASA/USAF/industry project is a natural extension of the Hyper-X Program (X-43A), which will demonstrate short duration ( 10 seconds) gaseous hydrogen-fueled scramjet powered flight at Mach 7 and Mach 10 using a heavyweight, largely heat sink construction, experimental engine. The X-43C Project will demonstrate sustained accelerating flight from Mach 5 to Mach 7 ( 4 minutes) using a flight-weight, fuel-cooled, scramjet engine powered by much denser liquid hydrocarbon fuel. The X-43C DV design flows from integrating USAF HyTech developed engine technologies with a NASA Air Breathing Launch Vehicle accelerator-class configuration and Hyper-X heritage vehicle systems designs. This paper describes the X-43C Project and provides background for NASA s current hypersonic flight demonstration efforts.
Ultrafast time scale X-rotation of cold atom storage qubit using Rubidium clock states
NASA Astrophysics Data System (ADS)
Song, Yunheung; Lee, Han-Gyeol; Kim, Hyosub; Jo, Hanlae; Ahn, Jaewook
2017-04-01
Ultrafast-time-scale optical interaction is a local operation on the electronic subspace of an atom, thus leaving its nuclear state intact. However, because atomic clock states are maximally entangled states of the electronic and nuclear degrees of freedom, their entire Hilbert space should be accessible only with local operations and classical communications (LOCC). Therefore, it may be possible to achieve hyperfine qubit gates only with electronic transitions. Here we show an experimental implementation of ultrafast X-rotation of atomic hyperfine qubits, in which an optical Rabi oscillation induces a geometric phase between the constituent fine-structure states, thus bringing about the X-rotation between the two ground hyperfine levels. In experiments, cold atoms in a magneto-optical trap were controlled with a femtosecond laser pulse from a Ti:sapphire laser amplifier. Absorption imaging of the as-controlled atoms initially in the ground hyperfine state manifested polarization dependence, strongly agreeing with the theory. The result indicates that single laser pulse implementations of THz clock speed qubit controls are feasible for atomic storage qubits. Samsung Science and Technology Foundation [SSTF-BA1301-12].
NASA Astrophysics Data System (ADS)
Gaffney, Monique Suzanne
1998-11-01
Metalorganic chemical vapor deposition (MOCVD) is a process used to manufacture electronic and optoelectronic devices that has traditionally lacked real-time growth monitoring and control. Controlling the growth rate and composition using the existing sensors, as well as advanced monitoring systems developed in-house, is shown to improve device quality. Specific MOCVD growth objectives are transformed into controller performance goals. Group III bubbler concentration variations, which perturb both growth rate and composition precision, are identified to be the primary disturbances. First a feed forward control system was investigated, which used an ultrasonic concentration monitor, located upstream in the process. This control strategy resulted in improved regulation of the gallium delivery rate by cancelling the sensed gallium bubbler concentration disturbances via the injection mass flow controller. The controller performance is investigated by growing GaInAs/InP superlattices. Results of growths performed under normal operating conditions and also under large perturbations include X-ray diffraction from the samples as well as real-time sensor signal data. High quality superlattices that display up to eight orders of satellite peaks are obtained under the feed forward compensation scheme, demonstrating improved layer-to-layer reproducibility of thickness and composition. The success of the feed forward control demonstration led to the development of a more complex downstream feedback control system. An ultraviolet absorption monitor was fabricated and retrofitted as a feedback control signal. A control-oriented model of the downstream process was developed for the feedback controller synthesis. Although challenged with both the photolysis and multi-gas detection issues common to UV absorption monitors, closed loop control with the UV sensor was performed and proved to be an effective method of disturbance rejection. An InP/GaInAs test structure was grown under both open and closed loop conditions. During the growth of a bulk GaInAs layer, an indium concentration disturbance was injected by way of the bubbler pressure control valve. The controller goal was to reject this concentration disturbance. The UV absorption real-time data, as well as both X-ray diffraction and photoluminescence post-growth sample measurements were used to evaluate the controller performance. All results indicate that the closed loop control system greatly improved the quality of the perturbed growth.
Human Spaceflight Recent Conjunctions of Interest
NASA Technical Reports Server (NTRS)
Browns, Ansley C.
2010-01-01
I. During each nine-hour shift (or upon request), the Orbital Safety Analyst (OSA) at JSpOC updates the entire tracked catalog with the latest tracking data from the SSN and screens this catalog against NASA s assets. a) For ISS operations, a 72-hour advance screening is performed. b) For Shuttle orbit operations, a 36-hour advance screening is performed. c) If a vehicle is performing a maneuver during the screening period, OSA uses post-reboost-trajectory data supplied by Mission Control Center-Houston (MCC-H) for screening. II. An automated process is used to detect any conjunctions within 10 x 40 x 40 km box (centered on the vehicle) using Special Perturbation (SP) processing: a) Box dimensions are Radial x Downtrack x Crosstrack. b) Any object found within this box has the tracking tasking level increased to improve (hopefully) its uncertainty in its current and predicted orbital trajectory. c) OSA informs NASA if any object is found inside a 2 x 25 x 25 km box then creates and sends an Orbital Conjunction Message (OCM) to NASA which contains detailed information about the conjunction. d) For Shuttle, the box size used for screening and reporting is altered for special operations (day of rendezvous, launch screening, etc.).
SpaceX Falcon Heavy Demo Flight - Press Site Activities
2018-02-06
The NASA News Center at Kennedy Space Center in Florida is filled with members of the news media awaiting liftoff of the SpaceX Falcon Heavy rocket from Launch Complex 39A. The demonstration flight will be a significant milestone for the world's premier multi-user spaceport. In 2014, NASA signed a property agreement with SpaceX for the use and operation of the center's pad 39A, where the company has launched Falcon 9 rockets and is preparing for the first Falcon Heavy. NASA also has Space Act Agreements in place with partners, such as SpaceX, to provide services needed to process and launch rockets and spacecraft.
SpaceX Falcon Heavy Demo Flight - Press Site Activities
2018-02-06
Employees, invited guests and members of the news media await liftoff of the SpaceX Falcon Heavy rocket from Launch Complex 39A at NASA’s Kennedy Space Center in Florida. The demonstration flight is a significant milestone for the world's premier multi-user spaceport. In 2014, NASA signed a property agreement with SpaceX for the use and operation of the center's pad 39A, where the company has launched Falcon 9 rockets and is preparing for the first Falcon Heavy. NASA also has Space Act Agreements in place with partners, such as SpaceX, to provide services needed to process and launch rockets and spacecraft.
Table-top soft x-ray microscope using laser-induced plasma from a pulsed gas jet.
Müller, Matthias; Mey, Tobias; Niemeyer, Jürgen; Mann, Klaus
2014-09-22
An extremely compact soft x-ray microscope operating in the "water window" region at the wavelength λ = 2.88 nm is presented, making use of a long-term stable and nearly debris-free laser-induced plasma from a pulsed nitrogen gas jet target. The well characterized soft x-ray radiation is focused by an ellipsoidal grazing incidence condenser mirror. Imaging of a sample onto a CCD camera is achieved with a Fresnel zone plate using magnifications up to 500x. The spatial resolution of the recorded microscopic images is about 100 nm as demonstrated for a Siemens star test pattern.
14 CFR Section 22 - General Reporting Instructions
Code of Federal Regulations, 2014 CFR
2014-01-01
... aircraft engines A X X X P-1.1 Statement of operations SA (2) NA NA P-1.2 Statement of operations Q (1) X X P-1(a) Interim operations report M X X X P-2 Notes to RSPA Form 41 report Q (1) X X P-5.1 Aircraft operating expenses Q(1), SA(2) X NA NA P-5.2 Aircraft operating expenses Q NA X X P-6 Operating expenses by...
14 CFR Section 22 - General Reporting Instructions
Code of Federal Regulations, 2011 CFR
2011-01-01
... aircraft engines A X X X P-1.1 Statement of operations SA (2) NA NA P-1.2 Statement of operations Q (1) X X P-1(a) Interim operations report M X X X P-2 Notes to RSPA Form 41 report Q (1) X X P-5.1 Aircraft operating expenses Q(1), SA(2) X NA NA P-5.2 Aircraft operating expenses Q NA X X P-6 Operating expenses by...
14 CFR Section 22 - General Reporting Instructions
Code of Federal Regulations, 2013 CFR
2013-01-01
... aircraft engines A X X X P-1.1 Statement of operations SA (2) NA NA P-1.2 Statement of operations Q (1) X X P-1(a) Interim operations report M X X X P-2 Notes to RSPA Form 41 report Q (1) X X P-5.1 Aircraft operating expenses Q(1), SA(2) X NA NA P-5.2 Aircraft operating expenses Q NA X X P-6 Operating expenses by...
14 CFR 22 - General Reporting Instructions
Code of Federal Regulations, 2012 CFR
2012-01-01
... aircraft engines A X X X P-1.1 Statement of operations SA (2) NA NA P-1.2 Statement of operations Q (1) X X P-1(a) Interim operations report M X X X P-2 Notes to RSPA Form 41 report Q (1) X X P-5.1 Aircraft operating expenses Q(1), SA(2) X NA NA P-5.2 Aircraft operating expenses Q NA X X P-6 Operating expenses by...
HUT Data Inspected at Marshall Space Flight Center During the STS-35 Mission
NASA Technical Reports Server (NTRS)
1990-01-01
The primary objective of the STS-35 mission was round the clock observation of the celestial sphere in ultraviolet and X-Ray astronomy with the Astro-1 observatory which consisted of four telescopes: the Hopkins Ultraviolet Telescope (HUT); the Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE); the Ultraviolet Imaging Telescope (UIT); and the Broad Band X-Ray Telescope (BBXRT). The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Teams of controllers and researchers directed on-orbit science operations, sent commands to the spacecraft, received data from experiments aboard the Space Shuttle, adjusted mission schedules to take advantage of unexpected science opportunities or unexpected results, and worked with crew members to resolve problems with their experiments. Due to loss of data used for pointing and operating the ultraviolet telescopes, MSFC ground teams were forced to aim the telescopes with fine tuning by the flight crew. This photo captures the activity of viewing HUT data in the Mission Manager Actions Room during the mission.
Montiel-Jarillo, Gabriela; Carrera, Julián; Suárez-Ojeda, María Eugenia
2017-04-01
Polyhydroxyalkanoates (PHA) are biopolymers that can be an alternative against conventional plastics. The study reported herein evaluated the enrichment of a mixed microbial culture (MMC) operated under feast/famine regime and different pHs in a sequencing batch reactor (SBR) using acetate as sole carbon source to produce polyhydroxyalkanoates (PHAs). The enrichment step was evaluated at controlled pH of 7.5 and also without pH control (averaged value of 9.0). The acetate uptake rate (-q S ) of both enrichments at the end of the experimental period exhibited similar behaviour being about 0.18CmolAcCmolX -1 h -1 and 0.19CmolAcCmolX -1 h -1 for SBR-A and SBR-B, respectively. However, the PHA-storing capacity of the biomass enriched without pH control was better, exhibiting a maximum PHA content of 36% (gPHAg -1 VSS) with a PHA production rate (q PHA ) of 0.16CmolPHACmolX -1 h -1 . Batch experiments were performed to evaluate PHA-storing capacity of the enriched culture at different pHs and nutrients concentrations. In the pH experiments (without nutrient limitation), it was found that in the absence of controlled pH, the enriched biomass exhibited a PHA content of 44% gPHAg -1 VSS with -q S and PHA to substrate yield (Y PHA/Ac ) of 0.57CmolAcCmolX -1 h -1 and 0.33CmolPHACmolAc -1 , respectively. Regarding the experiments at variable nutrients concentration (pH ranging 8.8 to 9.2), the results indicate that the PHA content in the enriched biomass is significantly higher being around 51% gPHAg -1 VSS under nitrogen limitation. This work demonstrated the feasibility of the enrichment of a MMC with PHA storage ability without pH control. Results also suggest that better PHAs contents and substrate uptake rates are obtained without controlling the pH in the accumulation step. Finally, this work also highlights the importance of understanding the role of nutrients concentration during the accumulation step. Copyright © 2017 Elsevier B.V. All rights reserved.
40 CFR 63.4751 - How do I demonstrate initial compliance with the emission limitations?
Code of Federal Regulations, 2010 CFR
2010-07-01
... emission rate without add-on controls option for any individual coating operation, for any group of coating operations in the affected source, or for all the coating operations in the affected source. You must use... operation in the affected source for which you do not use this option. To demonstrate initial compliance...
The X-43A Hyper-X Mach 7 Flight 2 Guidance, Navigation, and Control Overview and Flight Test Results
NASA Technical Reports Server (NTRS)
Bahm, Catherine; Baumann, Ethan; Martin, John; Bose, David; Beck, Roger E.; Strovers, Brian
2005-01-01
The objective of the Hyper-X program was to flight demonstrate an airframe-integrated hypersonic vehicle. On March 27, 2004, the Hyper-X program team successfully conducted flight 2 and achieved all of the research objectives. The Hyper-X research vehicle successfully separated from the Hyper-X launch vehicle and achieved the desired engine test conditions before the experiment began. The research vehicle rejected the disturbances caused by the cowl door opening and the fuel turning on and off and maintained the engine test conditions throughout the experiment. After the engine test was complete, the vehicle recovered and descended along a trajectory while performing research maneuvers. The last data acquired showed that the vehicle maintained control to the water. This report will provide an overview of the research vehicle guidance and control systems and the performance of the vehicle during the separation event and engine test. The research maneuvers were performed to collect data for aerodynamics and flight controls research. This report also will provide an overview of the flight controls related research and results.
NASA Technical Reports Server (NTRS)
Athale, R. A.; Lee, S. H.
1978-01-01
The paper describes the fabrication and operation of an optical parallel logic (OPAL) device which performs Boolean algebraic operations on binary images. Several logic operations on two input binary images were demonstrated using an 8 x 8 device with a CdS photoconductor and a twisted nematic liquid crystal. Two such OPAL devices can be interconnected to form a half-adder circuit which is one of the essential components of a CPU in a digital signal processor.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yu, Xiaobai; Wang, Xiaoxin; Zhang, Qinglin
Here, cermet solar thermal selective absorber coatings are an important component of high-efficiency concentrated solar power (CSP) receivers. The oxidation of the metal nanoparticles in cermet solar absorbers is a great challenge for vacuum-free operation. Recently, we have demonstrated that oxidation is kinetically retarded in solution processed, high-optical-performance Ni nanochain-SiO x cermet system compared to conventional Ni-Al 2O 3 system when annealed in air at 450–600 °C for several hours. However, for long-term, high-temperature applications in CSP systems, thermodynamically stable antioxidation behavior is highly desirable, which requires new mechanisms beyond kinetically reducing the oxidation rate. Towards this goal, in thismore » paper, we demonstrate that pre-operation annealing of Ni nanochain-SiO x cermets at 900 °C in N 2 forms the thermodynamically stable orthorhombic phase of NiSi at the Ni/SiO x interfaces, leading to self-terminated oxidation at 550 °C in air due to this interfacial engineering. In contrast, pre-operation annealing at a lower temperature of 750 °C in N 2 (as conducted in our previous work) cannot achieve interfacial NiSi formation directly, and further annealing in air at 450–600 °C for >4 h only leads to the formation of the less stable (metastable) hexagonal phase of NiSi. Therefore, the high-temperature pre-operation annealing is critical to form the desirable orthorhombic phase of NiSi at Ni/SiO x interfaces towards thermodynamically stable antioxidation behavior. Remarkably, with this improved interfacial engineering, the oxidation of 80-nm-diameter Ni nanochain-SiO x saturates after annealing at 550 °C in air for 12 h. Additional annealing at 550 °C in air for as long as 20 h (i.e., 32 h air annealing at >550 °C in total) has almost no further impact on the structural or optical properties of the coatings, the latter being very sensitive to any interfacial changes due to the localized surface plasmon resonances of the metal nanostructures. This phenomenon holds true for Ni nanoparticle diameter down to 40 nm in Ni-SiO x system, where the optical response remains stable for 53 h at 550 °C in air. The oxidation vs. time curve also shows saturation behavior deviating from the kinetic Deal-Grove oxidation model. These results strongly suggest a promising approach to thermodynamically stable, anti-oxidation Ni/SiO x cermet absorbers via interfacial engineering.« less
Yu, Xiaobai; Wang, Xiaoxin; Zhang, Qinglin; ...
2016-04-01
Here, cermet solar thermal selective absorber coatings are an important component of high-efficiency concentrated solar power (CSP) receivers. The oxidation of the metal nanoparticles in cermet solar absorbers is a great challenge for vacuum-free operation. Recently, we have demonstrated that oxidation is kinetically retarded in solution processed, high-optical-performance Ni nanochain-SiO x cermet system compared to conventional Ni-Al 2O 3 system when annealed in air at 450–600 °C for several hours. However, for long-term, high-temperature applications in CSP systems, thermodynamically stable antioxidation behavior is highly desirable, which requires new mechanisms beyond kinetically reducing the oxidation rate. Towards this goal, in thismore » paper, we demonstrate that pre-operation annealing of Ni nanochain-SiO x cermets at 900 °C in N 2 forms the thermodynamically stable orthorhombic phase of NiSi at the Ni/SiO x interfaces, leading to self-terminated oxidation at 550 °C in air due to this interfacial engineering. In contrast, pre-operation annealing at a lower temperature of 750 °C in N 2 (as conducted in our previous work) cannot achieve interfacial NiSi formation directly, and further annealing in air at 450–600 °C for >4 h only leads to the formation of the less stable (metastable) hexagonal phase of NiSi. Therefore, the high-temperature pre-operation annealing is critical to form the desirable orthorhombic phase of NiSi at Ni/SiO x interfaces towards thermodynamically stable antioxidation behavior. Remarkably, with this improved interfacial engineering, the oxidation of 80-nm-diameter Ni nanochain-SiO x saturates after annealing at 550 °C in air for 12 h. Additional annealing at 550 °C in air for as long as 20 h (i.e., 32 h air annealing at >550 °C in total) has almost no further impact on the structural or optical properties of the coatings, the latter being very sensitive to any interfacial changes due to the localized surface plasmon resonances of the metal nanostructures. This phenomenon holds true for Ni nanoparticle diameter down to 40 nm in Ni-SiO x system, where the optical response remains stable for 53 h at 550 °C in air. The oxidation vs. time curve also shows saturation behavior deviating from the kinetic Deal-Grove oxidation model. These results strongly suggest a promising approach to thermodynamically stable, anti-oxidation Ni/SiO x cermet absorbers via interfacial engineering.« less
Chen, Binbin; Chen, Pingfan; Xu, Haoran; Jin, Feng; Guo, Zhuang; Lan, Da; Wan, Siyuan; Gao, Guanyin; Chen, Feng; Wu, Wenbin
2016-12-21
Controlling functionalities in oxide heterostructures remains challenging for the rather complex interfacial interactions. Here, by modifying the interface properties with chemical doping, we achieve a nontrivial control over the ferromagnetism in ultrathin La 0.67 Ca 0.33 MnO 3 (LCMO) layer sandwiched between CaRu 1-x Ti x O 3 [CRTO(x)] epilayers. The Ti doping suppresses the interfacial electron transfer from CRTO(x) to LCMO side; as a result, a steadily decreased Curie temperature with increasing x, from 262 K at x = 0 to 186 K at x = 0.8, is observed for the structures with LCMO fixed at 3.2 nm. Moreover, for more insulating CRTO(x ≥ 0.5), the electron confinement induces an interfacial Mn-e g (x 2 -y 2 ) orbital order in LCMO which further attenuates the ferromagnetism. Also, in order to characterize the heterointerfaces, for the first time the doping- and thickness-dependent metal-insulator transitions in CRTO(x) films are examined. Our results demonstrate that the LCMO/CRTO(x) heterostructure could be a model system for investigating the interfacial multiple interactions in correlated oxides.
In-line localized monitoring of catalyst activity in selective catalytic NO.sub.x reduction systems
Muzio, Lawrence J [Laguna Niguel, CA; Smith, Randall A [Huntington Beach, CA
2009-12-22
Localized catalyst activity in an SCR unit for controlling emissions from a boiler, power plant, or any facility that generates NO.sub.x-containing flue gases is monitored by one or more modules that operate on-line without disrupting the normal operation of the facility. Each module is positioned over a designated lateral area of one of the catalyst beds in the SCR unit, and supplies ammonia, urea, or other suitable reductant to the catalyst in the designated area at a rate that produces an excess of the reductant over NO.sub.x on a molar basis through the designated area. Sampling probes upstream and downstream of the designated area draw samples of the gas stream for NO.sub.x analysis, and the catalyst activity is determined from the difference in NO.sub.x levels between the two probes.
2012-08-03
CAPE CANAVERAL, Fla. -- This is an artist's conception of Space Exploration Technologies', or SpaceX, crewed Dragon capsule atop the company's Falcon 9 rocket under development for NASA's Commercial Crew Program, or CCP. The integrated system was selected for CCP's Commercial Crew Integrated Capability, or CCiCap, initiative to propel America's next human space transportation system to low Earth orbit forward. Operating under a funded Space Act Agreement, or SAA, SpaceX will spend the next 21 months completing its design, conducting critical risk reduction testing on its spacecraft and launch vehicle, and showcasing how it would operate and manage missions from launch through orbit and landing, setting the stage for a future demonstration mission. To learn more about CCP, which is based at NASA's Kennedy Space Center in Florida and supported by NASA's Johnson Space Center in Houston, visit www.nasa.gov/commercialcrew. Image credit: SpaceX
F-15 Intelligent Flight Control System and Aeronautics Research at NASA Dryden
NASA Technical Reports Server (NTRS)
Brown, Nelson A.
2009-01-01
This viewgraph presentation reviews the F-15 Intelligent Flight Control System and Aeronautics including Autonomous Aerial Refueling Demonstrations, X-48B Blended Wing Body, F-15 Quiet Spike, and NF-15 Intelligent Flight Controls.
Commercial Crew Vehicle Ascent Abort Simulation and Analysis
NASA Technical Reports Server (NTRS)
Gnam, Christopher
2017-01-01
SpaceX and Boeing have been selected to develop and operate crew vehicles to transport astronauts to and from the International Space Station. Their design work is to be analyzed to ensure that they are meeting all of the safety and operational requirements put forth by NASA. Throughout my time here, I worked familiarized myself with the SpaceX Dragon Abort system, as well as the NASA Human-Systems Integration Requirements (HSIR). This included understanding the different abort scenarios, and how each one could potentially impact the astronaut crew. In addition, I familiarized myself with the simulation developed my NASA to test and analyze the Guidance Navigation and Control (GN&C) systems developed by SpaceX and Boeing.
X33 Reusable Launch Vehicle Control on Sliding Modes: Concepts for a Control System Development
NASA Technical Reports Server (NTRS)
Shtessel, Yuri B.
1998-01-01
Control of the X33 reusable launch vehicle is considered. The launch control problem consists of automatic tracking of the launch trajectory which is assumed to be optimally precalculated. It requires development of a reliable, robust control algorithm that can automatically adjust to some changes in mission specifications (mass of payload, target orbit) and the operating environment (atmospheric perturbations, interconnection perturbations from the other subsystems of the vehicle, thrust deficiencies, failure scenarios). One of the effective control strategies successfully applied in nonlinear systems is the Sliding Mode Control. The main advantage of the Sliding Mode Control is that the system's state response in the sliding surface remains insensitive to certain parameter variations, nonlinearities and disturbances. Employing the time scaling concept, a new two (three)-loop structure of the control system for the X33 launch vehicle was developed. Smoothed sliding mode controllers were designed to robustly enforce the given closed-loop dynamics. Simulations of the 3-DOF model of the X33 launch vehicle with the table-look-up models for Euler angle reference profiles and disturbance torque profiles showed a very accurate, robust tracking performance.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Momeni Hasan Abadi, Seyed Mohamad Amin, E-mail: momenihasana@wisc.edu; Booske, John H., E-mail: jhbooske@wisc.edu; Behdad, Nader, E-mail: behdad@wisc.edu
2016-08-07
We present a new approach to perform beam steering in reflecting type apertures such as reflectarray antennas. The proposed technique exploits macro-scale mechanical movements of parts of the structure to achieve two-dimensional microwave beam steering without using any solid-state devices or phase shifters integrated within the aperture of the antenna. The principles of operation of this microwave beam steering technique are demonstrated in an aperture occupied by ground-plane-backed, sub-wavelength capacitive patches with identical dimensions. We demonstrate that by tilting the ground plane underneath the entire patch array layer, a phase shift gradient can be created over the aperture of themore » reflectarray that determines the direction of the radiated beam. Changing the direction and slope of this phase shift gradient on the aperture allows for performing beam steering in two dimensions using only one control parameter (i.e., tilt vector of the ground plane). A proof-of-concept prototype of the structure operating at X-band is designed, fabricated, and experimentally characterized. Experiments demonstrate that small mechanical movements of the ground plane (in the order of 0.05λ{sub 0}) can be used to steer the beam direction in the ±10° in two dimensions. It is also demonstrated that this beam scanning range can be greatly enhanced to ±30° by applying this concept to the same structure when its ground plane is segmented.« less
NASA Astrophysics Data System (ADS)
Sinha, V.; Srivastava, A.; Lee, H. K.; Liu, X.
2013-05-01
The successful creation and operation of a neutron and X-ray combined computed tomography (NXCT) system has been demonstrated by researchers at the Missouri University of Science and Technology. The NXCT system has numerous applications in the field of material characterization and object identification in materials with a mixture of atomic numbers represented. Presently, the feasibility studies have been performed for explosive detection and homeland security applications, particularly in concealed material detection and determination of the light atomic number materials. These materials cannot be detected using traditional X-ray imaging. The new system has the capability to provide complete structural and compositional information due to the complementary nature of X-ray and neutron interactions with materials. The design of the NXCT system facilitates simultaneous and instantaneous imaging operation, promising enhanced detection capabilities of explosive materials, low atomic number materials and illicit materials for homeland security applications. In addition, a sample positioning system allowing the user to remotely and automatically manipulate the sample makes the system viable for commercial applications. Several explosives and weapon simulants have been imaged and the results are provided. The fusion algorithms which combine the data from the neutron and X-ray imaging produce superior images. This paper is a compete overview of the NXCT system for feasibility studies of explosive detection and homeland security applications. The design of the system, operation, algorithm development, and detection schemes are provided. This is the first combined neutron and X-ray computed tomography system in operation. Furthermore, the method of fusing neutron and X-ray images together is a new approach which provides high contrast images of the desired object. The system could serve as a standardized tool in nondestructive testing of many applications, especially in explosives detection and homeland security research.
[Eutrophication control in local area by physic-ecological engineering].
Li, Qiu-Hua; Xia, Pin-Hua; Wu, Hong; Lin, Tao; Zhang, You-Chun; Li, Cun-Xiong; Chen, Li-Li; Yang, Fan
2012-07-01
An integrated physical and ecological engineering experiment for ecological remediation was performed at the Maixi River bay in Baihua Reservoir Guizhou Province, China. The results show that eutrophic parameters, such as total nitrogen, total phosphorus, chlorophyll a and chemical oxygen demand from the experimental site (enclosed water) were significantly lower than those of the reference site. The largest differences between the sites were 0.61 mg x L(-1), 0.041 mg x L(-1), 23.06 microg x L(-1), 8.4 mg x L(-1) respectively; experimental site transparency was > 1.50 m which was significantly higher than that of the reference site. The eutrophic index of the experimental site was oligo-trophic and mid-trophic, while the control site was mid-trophic state and eutrophic state. Phytoplankton abundance was 2 125.5 x 10(4) cells x L(-1) in June, 2011 at the control site,but phytoplankton abundance was lower at the experimental site with 33 x 10(4) cells x L(-1). Cyanobacteria dominated phytoplankton biomass at both sites, however the experimental site consisted of a higher proportion of diatoms and dinoflagellates. After more than one year of operation, the ecological engineering technology effectively controlled the occurrence of algae blooms, changed phytoplankton community structure, and controlled the negative impacts of eutrophication. Integrating physical and ecological engineering technology could improve water quality for reservoirs on the Guizhou plateau.
Inverse kinematic-based robot control
NASA Technical Reports Server (NTRS)
Wolovich, W. A.; Flueckiger, K. F.
1987-01-01
A fundamental problem which must be resolved in virtually all non-trivial robotic operations is the well-known inverse kinematic question. More specifically, most of the tasks which robots are called upon to perform are specified in Cartesian (x,y,z) space, such as simple tracking along one or more straight line paths or following a specified surfacer with compliant force sensors and/or visual feedback. In all cases, control is actually implemented through coordinated motion of the various links which comprise the manipulator; i.e., in link space. As a consequence, the control computer of every sophisticated anthropomorphic robot must contain provisions for solving the inverse kinematic problem which, in the case of simple, non-redundant position control, involves the determination of the first three link angles, theta sub 1, theta sub 2, and theta sub 3, which produce a desired wrist origin position P sub xw, P sub yw, and P sub zw at the end of link 3 relative to some fixed base frame. Researchers outline a new inverse kinematic solution and demonstrate its potential via some recent computer simulations. They also compare it to current inverse kinematic methods and outline some of the remaining problems which will be addressed in order to render it fully operational. Also discussed are a number of practical consequences of this technique beyond its obvious use in solving the inverse kinematic question.
75 FR 81417 - Airworthiness Directives; Piper Aircraft, Inc. Model PA-28-161 Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-28
... authority digital engine control (FADEC) backup battery, replacing the supplement pilot's operating handbook... installation of a FADEC backup battery, replacement of the supplement pilot's operating handbook and FAA... backup battery 7 work-hours x $85 per $780 $1,375 Not hour = $595. applicable. Authority for This...
NASA Technical Reports Server (NTRS)
Colozza, Anthony J.; Scheiman, David A.; Bailey, Sheila (Technical Monitor)
2000-01-01
A system was constructed to demonstrate the power system operation of a solar powered aircraft. The system consists of a photovoltaic (PV) array, a charge controller, a battery, an electric motor and propeller. The system collects energy from the PV array and either utilizes this energy to operate an electric motor or stores it in a rechargeable battery for future use. The system has a control panel which displays the output of the array and battery as well as the total current going to the electric motor. The control panel also has a means for adjusting the output to the motor to control its speed. The entire system is regulated around 12 VDC.
Simulation Evaluation of Controller-Managed Spacing Tools under Realistic Operational Conditions
NASA Technical Reports Server (NTRS)
Callantine, Todd J.; Hunt, Sarah M.; Prevot, Thomas
2014-01-01
Controller-Managed Spacing (CMS) tools have been developed to aid air traffic controllers in managing high volumes of arriving aircraft according to a schedule while enabling them to fly efficient descent profiles. The CMS tools are undergoing refinement in preparation for field demonstration as part of NASA's Air Traffic Management (ATM) Technology Demonstration-1 (ATD-1). System-level ATD-1 simulations have been conducted to quantify expected efficiency and capacity gains under realistic operational conditions. This paper presents simulation results with a focus on CMS-tool human factors. The results suggest experienced controllers new to the tools find them acceptable and can use them effectively in ATD-1 operations.
[Experimental investigation of laser plasma soft X-ray source with gas target].
Ni, Qi-liang; Gong, Yan; Lin, Jing-quan; Chen, Bo; Cao, Jian-lin
2003-02-01
This paper describes a debris-free laser plasma soft X-ray source with a gas target, which has high operating frequency and can produce strong soft X-ray radiation. The valve of this light source is drived by a piezoelectrical ceramic whose operating frequency is up to 400 Hz. In comparison with laser plasma soft X-ray sources using metal target, the light source is debris-free. And it has higher operating frequency than gas target soft X-ray sources whose nozzle is controlled by a solenoid valve. A channel electron multiplier (CEM) operating in analog mode is used to detect the soft X-ray generated by the laser plasma source, and the CEM's output is fed to to a charge-sensitive preamplifier for further amplification purpose. Output charges from the CEM are proportional to the amplitude of the preamplifier's output voltage. Spectra of CO2, Xe and Kr at 8-14 nm wavelength which can be used for soft X-ray projection lithography are measured. The spectrum for CO2 consists of separate spectral lines originate mainly from the transitions in Li-like and Be-like ions. The Xe spectrum originating mainly from 4d-5f, 4d-4f, 4d-6p and 4d-5p transitions in multiply charged xenon ions. The spectrum for Kr consists of separate spectral lines and continuous broad spectra originating mainly from the transitions in Cu-, Ni-, Co- and Fe-like ions.
Observation of Electron Bernstein Wave Heating in the RFP
NASA Astrophysics Data System (ADS)
Seltzman, Andrew; Anderson, Jay; Goetz, John; Forest, Cary
2017-10-01
The first observation of RF heating in a reversed field pinch (RFP) using the electron Bernstein wave (EBW) has been demonstrated on MST. Efficient mode conversion of an outboard-launched X mode wave at 5.5 GHz leads to Doppler-shifted resonant absorption (ωrf = nωce-k||v||) for a broad range (n =1-7) of harmonics. The dynamics of EBW-heated electrons are measured using a spatial distribution of solid targets with diametrically opposed x-ray detectors. EBW heating produces a clear supra-thermal electron tail in MST. Radial deposition of the EBW is controlled with |B|and is measured using the HXR flux emitted from an insertable probe. In the thick-shelled MST RFP, the radial accessibility of EBW is limited to r/a >0.8 ( 10cm) by magnetic field error induced by the porthole necessary for the antenna. Experimental measurements show EBW propagation inward through a stochastic magnetic field. EBW-heated test electrons are used as a direct probe of edge (r/a >0.9) radial transport, showing a modest transition from `standard' to reduced-tearing RFP operation. Electron loss is too fast for collisional effects and implies a large non-collisional radial diffusivity. EBW heating has been demonstrated in reduced magnetic stochasticity plasmas with β = 15-20%. Work supported by USDOE.
Low-power resistive random access memory by confining the formation of conducting filaments
DOE Office of Scientific and Technical Information (OSTI.GOV)
Huang, Yi-Jen; Lee, Si-Chen, E-mail: sclee@ntu.edu.tw; Shen, Tzu-Hsien
2016-06-15
Owing to their small physical size and low power consumption, resistive random access memory (RRAM) devices are potential for future memory and logic applications in microelectronics. In this study, a new resistive switching material structure, TiO{sub x}/silver nanoparticles/TiO{sub x}/AlTiO{sub x}, fabricated between the fluorine-doped tin oxide bottom electrode and the indium tin oxide top electrode is demonstrated. The device exhibits excellent memory performances, such as low operation voltage (<±1 V), low operation power, small variation in resistance, reliable data retention, and a large memory window. The current-voltage measurement shows that the conducting mechanism in the device at the high resistancemore » state is via electron hopping between oxygen vacancies in the resistive switching material. When the device is switched to the low resistance state, conducting filaments are formed in the resistive switching material as a result of accumulation of oxygen vacancies. The bottom AlTiO{sub x} layer in the device structure limits the formation of conducting filaments; therefore, the current and power consumption of device operation are significantly reduced.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
1996-10-01
The objective of this project is to demonstrate and evaluate commercially available Selective Catalytic Reduction (SCR) catalysts from U.S., Japanese and European catalyst suppliers on a high-sulfur U.S. coal-fired boiler. SCR is a post-combustion nitrogen oxide (NO.) control technology that involves injecting ammonia into the flue gas generated from coal combustion in an electric utility boiler. The flue gas containing ammonia is then passed through a reactor that contains a specialized catalyst. In the presence of the catalyst, the ammonia reacts with NO. to convert it to nitrogen and water vapor. Although SCR is widely practiced in Japan and Europemore » on gas-, oil-, and low-sulfur coal- fired boilers, there are several technical uncertainties associated with applying SCR to U.S. coals. These uncertainties include: 1) potential catalyst deactivation due to poisoning by trace metal species present in U.S. coals that are not present in other fuels. 2) performance of the technology and effects on the balance-of- plant equipment in the presence of high amounts of SO{sub 2} and SO{sub 3}. 3) performance of a wide variety of SCR catalyst compositions, geometries and methods of manufacturer under typical high-sulfur coal-fired utility operating conditions. These uncertainties were explored by operating nine small-scale SCR reactors and simultaneously exposing different SCR catalysts to flue gas derived from the combustion of high sulfur U.S. coal. In addition, the test facility operating experience provided a basis for an economic study investigating the implementation of SCR technology.« less
Spin Coherence at the Nanoscale: Polymer Surfaces and Interfaces
DOE Office of Scientific and Technical Information (OSTI.GOV)
Epstein, Arthur J.
2013-09-10
Breakthrough results were achieved during the reporting period in the areas of organic spintronics. (A) For the first time the giant magnetic resistance (GMR) was observed in spin valve with an organic spacer. Thus we demonstrated the ability of organic semiconductors to transport spin in GMR devices using rubrene as a prototype for organic semiconductors. (B) We discovered the electrical bistability and spin valve effect in a ferromagnet /organic semiconductor/ ferromagnet heterojunction. The mechanism of switching between conducting phases and its potential applications were suggested. (C) The ability of V(TCNE)x to inject spin into organic semiconductors such as rubrene wasmore » demonstrated for the first time. The mechanisms of spin injection and transport from and into organic magnets as well through organic semiconductors were elucidated. (D) In collaboration with the group of OSU Prof. Johnston-Halperin we reported the successful extraction of spin polarized current from a thin film of the organic-based room temperature ferrimagnetic semiconductor V[TCNE]x and its subsequent injection into a GaAs/AlGaAs light-emitting diode (LED). Thus all basic steps for fabrication of room temperature, light weight, flexible all organic spintronic devices were successfully performed. (E) A new synthesis/processing route for preparation of V(TCNE)x enabling control of interface and film thicknesses at the nanoscale was developed at OSU. Preliminary results show these films are higher quality and what is extremely important they are substantially more air stable than earlier prepared V(TCNE)x. In sum the breakthrough results we achieved in the past two years form the basis of a promising new technology, Multifunctional Flexible Organic-based Spintronics (MFOBS). MFOBS technology enables us fabrication of full function flexible spintronic devices that operate at room temperature.« less
Management of Munitions Constituents in Soil Using Alkaline Hydrolysis: A Guide for Practitioners
2011-10-01
Jan -05 Feb-05 Mar-05 Apr-05 R D X (m g) Control Treated distance in meters distance...soil RDX concentration by bay during the field demonstration (PL = post-lime). 0 2 4 6 8 10 12 Dec Dec (PL) Jan Mar Apr Apr (PL) Jul Oct (PL) Jan ... Jan (PL) Mar Jun Jun (PL) 2005 2006 2007 R D X C on ce nt ra tio n (m g/ kg ) Bay 2 (control) Bay 4 (limed) Study Date R D X C on ce nt ra tio
Joint Center for Operational Analysis Journal. Volume 12, Issue 2, Summer 2010
2010-01-01
Peixoto. In 19X7. then-Major Keen attended Bra- zil’s Command and General Staff Course in Rio de Janeiro . Bra- zil. In 1988, then Captain Floriano...controlling DoD office). • DISTRIBUTION STATEMENT E . Distribution authorized to DoD Components only (fill in reason) (date of determination). Other... basic joint functions that integrate, synchronize, and direct joint operations, which arc: command and control, intelligence, fires, movement and
Solar electric propulsion thrust subsystem development
NASA Technical Reports Server (NTRS)
Masek, T. D.
1973-01-01
The Solar Electric Propulsion System developed under this program was designed to demonstrate all the thrust subsystem functions needed on an unmanned planetary vehicle. The demonstration included operation of the basic elements, power matching input and output voltage regulation, three-axis thrust vector control, subsystem automatic control including failure detection and correction capability (using a PDP-11 computer), operation of critical elements in thermal-vacuum-, zero-gravity-type propellant storage, and data outputs from all subsystem elements. The subsystem elements, functions, unique features, and test setup are described. General features and capabilities of the test-support data system are also presented. The test program culminated in a 1500-h computer-controlled, system-functional demonstration. This included simultaneous operation of two thruster/power conditioner sets. The results of this testing phase satisfied all the program goals.
Cholinergic Dysfunction in Fragile X Syndrome and Potential Intervention
Kesler, Shelli R; Lightbody, Amy A; Reiss, Allan L
2009-01-01
Males with fragile X syndrome are at risk for significant cognitive and behavioral deficits, particularly those involving executive prefrontal systems. Disruption of the cholinergic system secondary to fragile X mental retardation protein deficiency may contribute to the cognitive-behavioral impairments associated with fragile X. We measured choline in the dorsolateral prefrontal cortex of 9 males with fragile X syndrome and 9 age-matched typically developing controls using 1H magnetic resonance spectroscopy. Right choline/creatine was significantly reduced in the fragile X group compared to controls. In controls, both left and right choline was significantly positively correlated with intelligence and age was significantly negatively correlated with left choline. There were no correlations in the fragile X group. Subjects with fragile X syndrome participating in a pilot open-label trial of donepezil, an acetylcholinesterase inhibitor, demonstrated significantly improved cognitive-behavioral function. Studies utilizing biochemical neuroimaging techniques such as these have the potential to significantly impact the design of treatment strategies for fragile X syndrome and other genetic disorders by helping identify neurochemical targets for intervention as well as serving as metrics for treatment efficacy. PMID:19215057
DOD Role in Counterdrug Operations -- Can We Achieve Better Results?
1999-04-01
narcotics with high energy X - ray technologies. The DOD and the U.S. Customs Service are procuring X - ray systems with higher energy level, mobile X - ray ...flow of illegal drugs from source countries and a 20 percent reduction in domestic marijuana cultivation and methamphetamine production by the year 2002...cultivation and methamphetamine production by 2007.1 1 White House, The. National Drug Control Strategy: 1998. Washington D.C., U.S. Government Printing
NASA Astrophysics Data System (ADS)
Gong, Ren Hui; Jenkins, Brad; Sze, Raymond W.; Yaniv, Ziv
2014-03-01
The skills required for obtaining informative x-ray fluoroscopy images are currently acquired while trainees provide clinical care. As a consequence, trainees and patients are exposed to higher doses of radiation. Use of simulation has the potential to reduce this radiation exposure by enabling trainees to improve their skills in a safe environment prior to treating patients. We describe a low cost, high fidelity, fluoroscopy simulation system. Our system enables operators to practice their skills using the clinical device and simulated x-rays of a virtual patient. The patient is represented using a set of temporal Computed Tomography (CT) images, corresponding to the underlying dynamic processes. Simulated x-ray images, digitally reconstructed radiographs (DRRs), are generated from the CTs using ray-casting with customizable machine specific imaging parameters. To establish the spatial relationship between the CT and the fluoroscopy device, the CT is virtually attached to a patient phantom and a web camera is used to track the phantom's pose. The camera is mounted on the fluoroscope's intensifier and the relationship between it and the x-ray source is obtained via calibration. To control image acquisition the operator moves the fluoroscope as in normal operation mode. Control of zoom, collimation and image save is done using a keypad mounted alongside the device's control panel. Implementation is based on the Image-Guided Surgery Toolkit (IGSTK), and the use of the graphics processing unit (GPU) for accelerated image generation. Our system was evaluated by 11 clinicians and was found to be sufficiently realistic for training purposes.
X-43A Fluid and Environmental Systems: Ground and Flight Operation and Lessons Learned
NASA Technical Reports Server (NTRS)
Vachon, Michael Jacob; Grindle, Thomas J.; St.John, Clinton W.; Dowdell, David B.
2005-01-01
The X-43A Hyper-X program demonstrated the first successful flights of an airframe integrated scramjet powered hypersonic vehicle. The X-43A vehicles established successive world records for jet-powered vehicles at speeds of Mach 7 and Mach 10. The X-43A vehicle is a subscale version of proposed hypersonic reconnaissance strike aircraft. Scaled down to a length of 12 ft (3.66 m), the lifting body design with high fineness ratio resulted in very small internal space available for fluid systems and their corresponding environmental conditioning systems. Safe testing and operation of the X-43A fluid and environmental systems was critical for mission success, not only for the safety of the flight crew in the NASA B-52B carrier aircraft, but also to maintain the reliability of vehicle systems while exposed to dynamics and hostile conditions encountered during the boost trajectory. The X-43A fluid and environmental systems successfully managed explosive, pyrophoric, inert, and very high pressure gases without incident. This report presents a summary of the checkout and flight validation of the X-43A fluid systems. The testing used for mission assurance is summarized. System performance during captive carry and launch flights is presented. The lessons learned are also discussed.
Zhan, Wen-hua; Jiang, Zhu-ming; Tang, Yun; Wu, Yi-ping; Liu, Jin-wen; Zhang, Yan-jun; Chen, Wei; Liu, Tie; Yao, Chen
2007-07-03
To evaluate the impact of hypocaloric and hypo-nitrogen parenteral nutrition (PN) on infective complication rate, postoperative hospital stay and treatment cost in postoperative period. 120 patients with gastrointestinal tumors with the Nutrition Risk Screening (NRS) score of 3 or 4 undergoing radical gastrectomy in 5 hospitals were randomly assigned into 2 equal groups: control group, receiving PN with 30 (28 - 32) kcal x kg(-1) x d(-1) and nitrogen 0.20 (0.19 - 0.21) g x kg(-1) x d(-1) in regular "3 liter bag", and study group receiving calorie of 18 (range 16 - 20) kcal x kg(-1) x d(-1) and nitrogen of 0.10 (0.09 - 0.11) g x kg(-1) x d(-1) with triple chamber bag. PN support was infused continuously for at least six postoperative days through peripheral vein or peripherally inserted central catheter. The differences between these two groups in blood glucose level, infectious complication, phlebitis, systemic inflammatory response syndrome (SIRS), and duration of hospital stay after operation, and treatment cost. All data were evaluated by both intention to treat (ITT) analysis and per protocol (PP) analysis. There were no significant differences in the clinical baseline and operative types between the two groups. ITT analysis showed that the occurrence of hyperglycemia in postoperative period in the control group was 43.3%, significantly much higher than that in the study group (6.6%, P = 0.000). The infectious complication rate of the study group was 3.3%, significantly lower than that of the control group (16.6%, P = 0.0149), the phlebitis rate of the study group was 0.0%, significantly lower than that of the control group (18.3%, P = 0.0005). The SIRS rate of the study group was 25.0%, significantly lower than that of the control group (45.0%, P = 0.0216). PP analysis showed that the postoperative duration of hospital stay of the control group was 14.1 days +/- 5.8 days, significantly longer than that of the study group (12.4 days +/- 4.0 days, P = 0.047), the total PN cost of the study group was 3411.6 +/- 181.1 Yuan RMB, significantly higher than that of the control group (2945 +/- 162 Yuan RMB, P = 0.000); but the total post-operative cost of treatment of the control group was 13156 +/- 3282 Yuan RMB, significantly higher than that of the study group (11 642 +/- 3019 Yuan RMB, P = 0.010); and the time for compounding of the study group was 5.0 min +/- 1.7 min, significantly shorter than that of the control group (15.4 min +/- 3.7 min, P = 0.000). Hypocaloric and hypo-nitrogen PN in postoperative days 1 - 6 in patients with scores 3 or 4 decreases the rates of hyperglycemia, infectious complications, phlebitis, and SIRS, shortens the postoperative hospital stay, and lowers the cost of treatment comparing with conventional PN. The use of triple chamber bag shortens the compounding time of PN.
NASA Astrophysics Data System (ADS)
Gann, Eliot; Watson, Anne; Tumbleston, John R.; Cochran, Justin; Yan, Hongping; Wang, Cheng; Seok, Jaewook; Chabinyc, Michael; Ade, Harald
2014-12-01
The internal structures of thin films, particularly interfaces between different materials, are critical to system properties and performance across many disciplines, but characterization of buried interface topography is often unfeasible. In this work, we demonstrate that grazing resonant soft x-ray scattering (GRSoXS), a technique measuring diffusely scattered soft x rays from grazing incidence, can reveal the statistical topography of buried thin-film interfaces. By controlling and predicting the x-ray electric field intensity throughout the depth of the film and simultaneously the scattering contrast between materials, we are able to unambiguously identify the microstructure at different interfaces of a model polymer bilayer system. We additionally demonstrate the use of GRSoXS to selectively measure the topography of the surface and buried polymer-polymer interface in an organic thin-film transistor, revealing different microstructure and markedly differing evolution upon annealing. In such systems, where only indirect control of interface topography is possible, accurate measurement of the structure of interfaces for feedback is critically important. While we demonstrate the method here using organic materials, we also show that the technique is readily extendable to any thin-film system with elemental or chemical contrasts exploitable at absorption edges.
Lillaney, Prasheel; Shin, Mihye; Hinshaw, Waldo; Bennett, N. Robert; Pelc, Norbert; Fahrig, Rebecca
2013-01-01
Purpose: Using hybrid x-ray/MR (XMR) systems for image guidance during interventional procedures could enhance the diagnosis and treatment of neurologic, oncologic, cardiovascular, and other disorders. The authors propose a close proximity hybrid system design in which a C-arm fluoroscopy unit is placed immediately adjacent to the solenoid magnet of a MR system with a minimum distance of 1.2 m between the x-ray and MR imaging fields of view. Existing rotating anode x-ray tube designs fail within MR fringe field environments because the magnetic fields alter the electron trajectories in the x-ray tube and act as a brake on the induction motor, reducing the rotation speed of the anode. In this study the authors propose a novel motor design that avoids the anode rotation speed reduction. Methods: The proposed design replaces the permanent magnet stator found in brushed dc motors with the radial component of the MR fringe field. The x-ray tube is oriented such that the radial component of the MR fringe field is orthogonal to the cathode-anode axis. Using a feedback position sensor and the support bearings as electrical slip rings, the authors use electrical commutation to eliminate the need for mechanical brushes and commutators. A vacuum compatible prototype of the proposed motor design was assembled, and its performance was evaluated at various operating conditions. The prototype consisted of a 3.1 in. diameter anode rated at 300 kHU with a ceramic rotor that was 5.6 in. in length and had a 2.9 in. diameter. The material chosen for all ceramic components was MACOR, a machineable glass ceramic developed by Corning Inc. The approximate weight of the entire assembly was 1750 g. The maximum rotation speed, angular acceleration, and acceleration time of the motor design were investigated, as well as the dependence of these parameters on rotor angular offset, magnetic field strength, and field orientation. The resonance properties of the authors’ assembly were also evaluated to determine its stability during acceleration, and a pulse width modulation algorithm was implemented to control the rotation speed of the motor. Results: At a magnetic flux density of 41 mT orthogonal to the axis of rotation (on the lower end of the expected flux density in the MR suite) the maximum speed of the motor was found to be 5150 revolutions per minute (rpm). The acceleration time necessary to reach 3000 rpm was found to be approximately 10 s at 59 mT. The resonance frequency of the assembly with the anode attached was 1310 rpm (21.8 Hz) which is far below the desired operating speeds. Pulse width modulation provides an effective method to control the speed of the motor with a resolution of 100 rpm. Conclusions: The proposed design can serve as a direct replacement to the conventional induction motor used in rotating anode x-ray tubes. It does not suffer from a reduced rotation speed when operating in a MR environment. The presence of chromic steel bearings in the prototype prevented testing at the higher field strengths, and future iterations of the design could eliminate this shortcoming. The prototype assembly demonstrates proof of concept of the authors’ design and overcomes one of the major obstacles for a MR compatible rotating anode x-ray tube. PMID:23387764
Lillaney, Prasheel; Shin, Mihye; Hinshaw, Waldo; Bennett, N Robert; Pelc, Norbert; Fahrig, Rebecca
2013-02-01
Using hybrid x-ray∕MR (XMR) systems for image guidance during interventional procedures could enhance the diagnosis and treatment of neurologic, oncologic, cardiovascular, and other disorders. The authors propose a close proximity hybrid system design in which a C-arm fluoroscopy unit is placed immediately adjacent to the solenoid magnet of a MR system with a minimum distance of 1.2 m between the x-ray and MR imaging fields of view. Existing rotating anode x-ray tube designs fail within MR fringe field environments because the magnetic fields alter the electron trajectories in the x-ray tube and act as a brake on the induction motor, reducing the rotation speed of the anode. In this study the authors propose a novel motor design that avoids the anode rotation speed reduction. The proposed design replaces the permanent magnet stator found in brushed dc motors with the radial component of the MR fringe field. The x-ray tube is oriented such that the radial component of the MR fringe field is orthogonal to the cathode-anode axis. Using a feedback position sensor and the support bearings as electrical slip rings, the authors use electrical commutation to eliminate the need for mechanical brushes and commutators. A vacuum compatible prototype of the proposed motor design was assembled, and its performance was evaluated at various operating conditions. The prototype consisted of a 3.1 in. diameter anode rated at 300 kHU with a ceramic rotor that was 5.6 in. in length and had a 2.9 in. diameter. The material chosen for all ceramic components was MACOR, a machineable glass ceramic developed by Corning Inc. The approximate weight of the entire assembly was 1750 g. The maximum rotation speed, angular acceleration, and acceleration time of the motor design were investigated, as well as the dependence of these parameters on rotor angular offset, magnetic field strength, and field orientation. The resonance properties of the authors' assembly were also evaluated to determine its stability during acceleration, and a pulse width modulation algorithm was implemented to control the rotation speed of the motor. At a magnetic flux density of 41 mT orthogonal to the axis of rotation (on the lower end of the expected flux density in the MR suite) the maximum speed of the motor was found to be 5150 revolutions per minute (rpm). The acceleration time necessary to reach 3000 rpm was found to be approximately 10 s at 59 mT. The resonance frequency of the assembly with the anode attached was 1310 rpm (21.8 Hz) which is far below the desired operating speeds. Pulse width modulation provides an effective method to control the speed of the motor with a resolution of 100 rpm. The proposed design can serve as a direct replacement to the conventional induction motor used in rotating anode x-ray tubes. It does not suffer from a reduced rotation speed when operating in a MR environment. The presence of chromic steel bearings in the prototype prevented testing at the higher field strengths, and future iterations of the design could eliminate this shortcoming. The prototype assembly demonstrates proof of concept of the authors' design and overcomes one of the major obstacles for a MR compatible rotating anode x-ray tube.
Combustion interaction with radiation-cooled chambers
NASA Technical Reports Server (NTRS)
Rosenberg, S. D.; Jassowski, D. M.; Barlow, R.; Lucht, R.; Mccarty, K.
1990-01-01
Over 15 hours of thruster operation at temperatures between 1916 and 2246 C without failure or erosion has been demonstrated using iridium-coated rhenium chamber materials with nitrogen tetroxide/monomethylhydrazine propellants operating over a mixture ratio range of 1.60-2.05. Research is now under way to provide a basic understanding of the mechanisms which make high-temperature operation possible and to extend the capability to a wider range of conditions, including other propellant combinations and chamber materials. Techniques have been demonstrated for studying surface fracture phenomena. These include surface Raman and Auger for study of oxide formation, surface Raman and X-ray diffraction to determine the oxide phase, Auger to study oxide stoichiometry, and sputter Auger to study interdiffusion of alloy species.
Choi, Sihyuk; Yoo, Seonyoung; Kim, Jiyoun; Park, Seonhye; Jun, Areum; Sengodan, Sivaprakash; Kim, Junyoung; Shin, Jeeyoung; Jeong, Hu Young; Choi, YongMan; Kim, Guntae; Liu, Meilin
2013-01-01
Solid oxide fuel cells (SOFC) are the cleanest, most efficient, and cost-effective option for direct conversion to electricity of a wide variety of fuels. While significant progress has been made in anode materials with enhanced tolerance to coking and contaminant poisoning, cathodic polarization still contributes considerably to energy loss, more so at lower operating temperatures. Here we report a synergistic effect of co-doping in a cation-ordered double-perovskite material, PrBa0.5Sr0.5Co(2-x)Fe(x)O(5+δ), which has created pore channels that dramatically enhance oxygen ion diffusion and surface oxygen exchange while maintaining excellent compatibility and stability under operating conditions. Test cells based on these cathode materials demonstrate peak power densities ~2.2 W cm(-2) at 600°C, representing an important step toward commercially viable SOFC technologies.
Curved diamond-crystal spectrographs for x-ray free-electron laser noninvasive diagnostics.
Terentyev, Sergey; Blank, Vladimir; Kolodziej, Tomasz; Shvyd'ko, Yuri
2016-12-01
We report on the manufacturing and X-ray tests of bent diamond-crystal X-ray spectrographs, designed for noninvasive diagnostics of the X-ray free-electron laser (XFEL) spectra in the spectral range from 5 to 15 keV. The key component is a curved, 20-μm thin, single crystalline diamond triangular plate in the (110) orientation. The radius of curvature can be varied between R = 0.6 m and R = 0.1 m in a controlled fashion, ensuring imaging in a spectral window of up to 60 eV for ≃8 keV X-rays. All of the components of the bending mechanism (about 10 parts) are manufactured from diamond, thus ensuring safe operations in intense XFEL beams. The spectrograph is transparent to 88% for 5-keV photons and to 98% for 15-keV photons. Therefore, it can be used for noninvasive diagnostics of the X-ray spectra during XFEL operations.
Curved diamond-crystal spectrographs for x-ray free-electron laser noninvasive diagnostics
Terentyev, Sergey; Blank, Vladimir; Kolodziej, Tomasz; ...
2016-12-29
Here, we report on the manufacturing and X-ray tests of bent diamond-crystal X-ray spectrographs, designed for noninvasive diagnostics of the X-ray free-electron laser (XFEL) spectra in the spectral range from 5 to 15 keV. The key component is a curved, 20-µm thin, single crystalline diamond triangular plate in the (110) orientation. The radius of curvature can be varied between R = 0.6 m and R = 0.1 m in a controlled fashion, ensuring imaging in a spectral window of up to 60 eV for ' 8 keV X-rays. All of the components of the bending mechanism (about 10 parts) aremore » manufactured from diamond, thus ensuring safe operations in intense XFEL beams. The spectrograph is transparent to 88% for 5-keV photons, and to 98% for 15-keV photons. Therefore, it can be used for noninvasive diagnostics of the X-ray spectra during XFEL operations.« less
Curved diamond-crystal spectrographs for x-ray free-electron laser noninvasive diagnostics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Terentyev, Sergey; Blank, Vladimir; Kolodziej, Tomasz
Here, we report on the manufacturing and X-ray tests of bent diamond-crystal X-ray spectrographs, designed for noninvasive diagnostics of the X-ray free-electron laser (XFEL) spectra in the spectral range from 5 to 15 keV. The key component is a curved, 20-µm thin, single crystalline diamond triangular plate in the (110) orientation. The radius of curvature can be varied between R = 0.6 m and R = 0.1 m in a controlled fashion, ensuring imaging in a spectral window of up to 60 eV for ' 8 keV X-rays. All of the components of the bending mechanism (about 10 parts) aremore » manufactured from diamond, thus ensuring safe operations in intense XFEL beams. The spectrograph is transparent to 88% for 5-keV photons, and to 98% for 15-keV photons. Therefore, it can be used for noninvasive diagnostics of the X-ray spectra during XFEL operations.« less
Tutorial on X-ray photon counting detector characterization.
Ren, Liqiang; Zheng, Bin; Liu, Hong
2018-01-01
Recent advances in photon counting detection technology have led to significant research interest in X-ray imaging. As a tutorial level review, this paper covers a wide range of aspects related to X-ray photon counting detector characterization. The tutorial begins with a detailed description of the working principle and operating modes of a pixelated X-ray photon counting detector with basic architecture and detection mechanism. Currently available methods and techniques for charactering major aspects including energy response, noise floor, energy resolution, count rate performance (detector efficiency), and charge sharing effect of photon counting detectors are comprehensively reviewed. Other characterization aspects such as point spread function (PSF), line spread function (LSF), contrast transfer function (CTF), modulation transfer function (MTF), noise power spectrum (NPS), detective quantum efficiency (DQE), bias voltage, radiation damage, and polarization effect are also remarked. A cadmium telluride (CdTe) pixelated photon counting detector is employed for part of the characterization demonstration and the results are presented. This review can serve as a tutorial for X-ray imaging researchers and investigators to understand, operate, characterize, and optimize photon counting detectors for a variety of applications.
CheMin Instrument Performance and Calibration on Mars
NASA Technical Reports Server (NTRS)
Vaniman, D. T.; Blake, D. F.; Morookian, J. M.; Yen, A. S.; Ming, D. W.; Morris, R. V.; Achilles, C. N.; Bish, D. L.; Chipera, S. J.; Morrison, S. M.;
2013-01-01
The CheMin (Chemistry and Mineralogy) instrument on the Mars Science Laboratory rover Curiosity uses a CCD detector and a Co-anode X-ray tube source to acquire both mineralogy (from the pattern of Co diffraction) and chemical information (from energies of fluoresced X-rays). A key component of the CheMin instrument is the ability to move grains within sample cells during analysis, providing multiple, random grain orientations that disperse diffracted X-ray photons along Debye rings rather than producing discrete Laue spots. This movement is accomplished by piezoelectric vibration of the sample cells. A cryocooler is used to maintain the CCD at a temperature at about -50 C in order to obtain energy resolution better than 250 eV, allowing discrimination of diffracted Co K X-rays from Fe K and other fluorescent X-rays. A detailed description of CheMin is provided in [1]. The CheMin flight model (FM) is mounted within the body of Curiosity and has been operating on Mars since August 6, 2012. An essentially identical sister instrument, the CheMin demonstration model (DM), is operated in a Mars environment chamber at JPL.
Exposure of hospital operating room personnel to potentially harmful environmental agents
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sass-Kortsak, A.M.; Purdham, J.T.; Bozek, P.R.
1992-03-01
Epidemiologic studies of risk to reproductive health arising from the operating room environment have been inconclusive and lack quantitative exposure information. This study was undertaken to quantify exposure of operating room (OR) personnel to anesthetic agents, x-radiation, methyl methacrylate, and ethylene oxide and to determine how exposure varies with different operating room factors. Exposures of anesthetists and nurses to these agents were determined in selected operating rooms over three consecutive days. Each subject was asked to wear an x-radiation dosimeter for 1 month. Exposure to anesthetic agents was found to be influenced by the age of the OR facility, typemore » of surgical service, number of procedures carried out during the day, type of anesthetic circuitry, and method of anesthesia delivery. Anesthetists were found to have significantly greater exposures than OR nurses. Exposure of OR personnel to ethylene oxide, methyl methacrylate, and x-radiation were well within existing standards. Exposure of anesthetists and nurses to anesthetic agents, at times, was in excess of Ontario exposure guidelines, despite improvements in the control of anesthetic pollution.« less
NASA Technical Reports Server (NTRS)
Cosentino, Gary B.
2008-01-01
The Joint Unmanned Combat Air Systems (J-UCAS) program is a collaborative effort between the Defense Advanced Research Project Agency (DARPA), the US Air Force (USAF) and the US Navy (USN). Together they have reviewed X-45A flight test site processes and personnel as part of a system demonstration program for the UCAV-ATD Flight Test Program. The goal was to provide a disciplined controlled process for system integration and testing and demonstration flight tests. NASA's Dryden Flight Research Center (DFRC) acted as the project manager during this effort and was tasked with the responsibilities of range and ground safety, the provision of flight test support and infrastructure and the monitoring of technical and engineering tasks. DFRC also contributed their engineering knowledge through their contributions in the areas of autonomous ground taxi control development, structural dynamics testing and analysis and the provision of other flight test support including telemetry data, tracking radars, and communications and control support equipment. The Air Force Flight Test Center acted at the Deputy Project Manager in this effort and was responsible for the provision of system safety support and airfield management and air traffic control services, among other supporting roles. The T-33 served as a J-UCAS surrogate aircraft and demonstrated flight characteristics similar to that of the the X-45A. The surrogate served as a significant risk reduction resource providing mission planning verification, range safety mission assessment and team training, among other contributions.
Solon, K; Flores-Alsina, X; Kazadi Mbamba, C; Ikumi, D; Volcke, E I P; Vaneeckhaute, C; Ekama, G; Vanrolleghem, P A; Batstone, D J; Gernaey, K V; Jeppsson, U
2017-04-15
The objective of this paper is to report the effects that control/operational strategies may have on plant-wide phosphorus (P) transformations in wastewater treatment plants (WWTP). The development of a new set of biological (activated sludge, anaerobic digestion), physico-chemical (aqueous phase, precipitation, mass transfer) process models and model interfaces (between water and sludge line) were required to describe the required tri-phasic (gas, liquid, solid) compound transformations and the close interlinks between the P and the sulfur (S) and iron (Fe) cycles. A modified version of the Benchmark Simulation Model No. 2 (BSM2) (open loop) is used as test platform upon which three different operational alternatives (A 1 , A 2 , A 3 ) are evaluated. Rigorous sensor and actuator models are also included in order to reproduce realistic control actions. Model-based analysis shows that the combination of an ammonium ( [Formula: see text] ) and total suspended solids (X TSS ) control strategy (A 1 ) better adapts the system to influent dynamics, improves phosphate [Formula: see text] accumulation by phosphorus accumulating organisms (X PAO ) (41%), increases nitrification/denitrification efficiency (18%) and reduces aeration energy (E aeration ) (21%). The addition of iron ( [Formula: see text] ) for chemical P removal (A 2 ) promotes the formation of ferric oxides (X HFO-H , X HFO-L ), phosphate adsorption (X HFO-H,P , X HFO-L,P ), co-precipitation (X HFO-H,P,old , X HFO-L,P,old ) and consequently reduces the P levels in the effluent (from 2.8 to 0.9 g P.m -3 ). This also has an impact on the sludge line, with hydrogen sulfide production ( [Formula: see text] ) reduced (36%) due to iron sulfide (X FeS ) precipitation. As a consequence, there is also a slightly higher energy production (E production ) from biogas. Lastly, the inclusion of a stripping and crystallization unit (A 3 ) for P recovery reduces the quantity of P in the anaerobic digester supernatant returning to the water line and allows potential struvite ( [Formula: see text] ) recovery ranging from 69 to 227 kg.day -1 depending on: (1) airflow (Q stripping ); and, (2) magnesium ( [Formula: see text] ) addition. All the proposed alternatives are evaluated from an environmental and economical point of view using appropriate performance indices. Finally, some deficiencies and opportunities of the proposed approach when performing (plant-wide) wastewater treatment modelling/engineering projects are discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.
Two X-38 Ship Demonstrators in Development at NASA Johnson Space Flight Center
NASA Technical Reports Server (NTRS)
1999-01-01
This photo shows two X-38 Crew Return Vehicle technology demonstrators under development at NASA's Johnson Space Flight Center, Houston, Texas. The X-38 Crew Return Vehicle (CRV) research project is designed to develop the technology for a prototype emergency crew return vehicle, or lifeboat, for the International Space Station. The project is also intended to develop a crew return vehicle design that could be modified for other uses, such as a joint U.S. and international human spacecraft that could be launched on the French Ariane-5 Booster. The X-38 project is using available technology and off-the-shelf equipment to significantly decrease development costs. Original estimates to develop a capsule-type crew return vehicle were estimated at more than $2 billion. X-38 project officials have estimated that development costs for the X-38 concept will be approximately one quarter of the original estimate. Off-the-shelf technology is not necessarily 'old' technology. Many of the technologies being used in the X-38 project have never before been applied to a human-flight spacecraft. For example, the X-38 flight computer is commercial equipment currently used in aircraft and the flight software operating system is a commercial system already in use in many aerospace applications. The video equipment for the X-38 is existing equipment, some of which has already flown on the space shuttle for previous NASA experiments. The X-38's primary navigational equipment, the Inertial Navigation System/Global Positioning System, is a unit already in use on Navy fighters. The X-38 electromechanical actuators come from previous joint NASA, U.S. Air Force, and U.S. Navy research and development projects. Finally, an existing special coating developed by NASA will be used on the X-38 thermal tiles to make them more durable than those used on the space shuttles. The X-38 itself was an unpiloted lifting body designed at 80 percent of the size of a projected emergency crew return vehicle for the International Space Station, although two later versions were planned at 100 percent of the CRV size. The X-38 and the actual CRV are patterned after a lifting-body shape first employed in the Air Force-NASA X-24 lifting-body project in the early to mid-1970s. The current vehicle design is base lined with life support supplies for about nine hours of orbital free flight from the space station. It's landing will be fully automated with backup systems which allow the crew to control orientation in orbit, select a deorbit site, and steer the parafoil, if necessary. The X-38 vehicles (designated V131, V132, and V-131R) are 28.5 feet long, 14.5 feet wide, and weigh approximately 16,000 pounds on average. The vehicles have a nitrogen-gas-operated attitude control system and a bank of batteries for internal power. The actual CRV to be flown in space was expected to be 30 feet long. The X-38 project is a joint effort between the Johnson Space Center, Houston, Texas (JSC), Langley Research Center, Hampton, Virginia (LaRC) and Dryden Flight Research Center, Edwards, California (DFRC) with the program office located at JSC. A contract was awarded to Scaled Composites, Inc., Mojave, California, for construction of the X-38 test airframes. The first vehicle was delivered to the JSC in September 1996. The vehicle was fitted with avionics, computer systems and other hardware at Johnson. A second vehicle was delivered to JSC in December 1996. Flight research with the X-38 at Dryden began with an unpiloted captive-carry flight in which the vehicle remained attached to its future launch vehicle, Dryden's B-52 008. There were four captive flights in 1997 and three in 1998, plus the first drop test on March 12, 1998, using the parachutes and parafoil. Further captive and drop tests occurred in 1999. In March 2000 Vehicle 132 completed its third and final free flight in the highest, fastest, and longest X-38 flight to date. It was released at an altitude of 39,000 feet and flew freely for 45 seconds, reaching a speed of over 500 miles per hour before deploying its parachutes for a landing on Rogers Dry Lakebed. In the drop tests, the X-38 vehicles have been autonomous after airlaunch from the B-52. After they deploy the parafoil, they have remained autonomous, but there is also a manual mode with controls from the ground.
The First X-38 Technology Demonstrator (V-131) Shown with Modifications to the Rear to Conform More
NASA Technical Reports Server (NTRS)
1999-01-01
The first X-38 technology demonstrator (V-131) is seen here undergoing modifications to the rear to conform more to the shape of the future Crew Return Vehicle (CRV) The X-38 Crew Return Vehicle (CRV) research project is designed to develop the technology for a prototype emergency crew return vehicle, or lifeboat, for the International Space Station. The project is also intended to develop a crew return vehicle design that could be modified for other uses, such as a joint U.S. and international human spacecraft that could be launched on the French Ariane-5 Booster. The X-38 project is using available technology and off-the-shelf equipment to significantly decrease development costs. Original estimates to develop a capsule-type crew return vehicle were estimated at more than $2 billion. X-38 project officials have estimated that development costs for the X-38 concept will be approximately one quarter of the original estimate. Off-the-shelf technology is not necessarily 'old' technology. Many of the technologies being used in the X-38 project have never before been applied to a human-flight spacecraft. For example, the X-38 flight computer is commercial equipment currently used in aircraft and the flight software operating system is a commercial system already in use in many aerospace applications. The video equipment for the X-38 is existing equipment, some of which has already flown on the space shuttle for previous NASA experiments. The X-38's primary navigational equipment, the Inertial Navigation System/Global Positioning System, is a unit already in use on Navy fighters. The X-38 electromechanical actuators come from previous joint NASA, U.S. Air Force, and U.S. Navy research and development projects. Finally, an existing special coating developed by NASA will be used on the X-38 thermal tiles to make them more durable than those used on the space shuttles. The X-38 itself was an unpiloted lifting body designed at 80 percent of the size of a projected emergency crew return vehicle for the International Space Station, although two later versions were planned at 100 percent of the CRV size. The X-38 and the actual CRV are patterned after a lifting-body shape first employed in the Air Force-NASA X-24 lifting-body project in the early to mid-1970s. The current vehicle design is base lined with life support supplies for about nine hours of orbital free flight from the space station. It's landing will be fully automated with backup systems which allow the crew to control orientation in orbit, select a deorbit site, and steer the parafoil, if necessary. The X-38 vehicles (designated V131, V132, and V-131R) are 28.5 feet long, 14.5 feet wide, and weigh approximately 16,000 pounds on average. The vehicles have a nitrogen-gas-operated attitude control system and a bank of batteries for internal power. The actual CRV to be flown in space was expected to be 30 feet long. The X-38 project is a joint effort between the Johnson Space Center, Houston, Texas (JSC), Langley Research Center, Hampton, Virginia (LaRC) and Dryden Flight Research Center, Edwards, California (DFRC) with the program office located at JSC. A contract was awarded to Scaled Composites, Inc., Mojave, California, for construction of the X-38 test airframes. The first vehicle was delivered to the JSC in September 1996. The vehicle was fitted with avionics, computer systems and other hardware at Johnson. A second vehicle was delivered to JSC in December 1996. Flight research with the X-38 at Dryden began with an unpiloted captive-carry flight in which the vehicle remained attached to its future launch vehicle, Dryden's B-52 008. There were four captive flights in 1997 and three in 1998, plus the first drop test on March 12, 1998, using the parachutes and parafoil. Further captive and drop tests occurred in 1999. In March 2000 Vehicle 132 completed its third and final free flight in the highest, fastest, and longest X-38 flight to date. It was released at an altitude of 39,000 feet and flew freely for 45 seconds, reaching a speed of over 500 miles per hour before deploying its parachutes for a landing on Rogers Dry Lakebed. In the drop tests, the X-38 vehicles have been autonomous after airlaunch from the B-52. After they deploy the parafoil, they have remained autonomous, but there is also a manual mode with controls from the ground.
X-38 Prototype Technology Demonstrator for the Crew Return Vehicle (CRV) and Project Managers Bob Ba
NASA Technical Reports Server (NTRS)
1999-01-01
Bob Baron of the Dryden Flight Research Center (left) and Brian Anderson of the Johnson Space Flight Center (right) flank an X-38 prototype Crew Return Vehicle technology demonstrator under construction at the Johnson Space Center, Houston, Texas. The X-38 Crew Return Vehicle (CRV) research project is designed to develop the technology for a prototype emergency crew return vehicle, or lifeboat, for the International Space Station. The project is also intended to develop a crew return vehicle design that could be modified for other uses, such as a joint U.S. and international human spacecraft that could be launched on the French Ariane-5 Booster. The X-38 project is using available technology and off-the-shelf equipment to significantly decrease development costs. Original estimates to develop a capsule-type crew return vehicle were estimated at more than $2 billion. X-38 project officials have estimated that development costs for the X-38 concept will be approximately one quarter of the original estimate. Off-the-shelf technology is not necessarily 'old' technology. Many of the technologies being used in the X-38 project have never before been applied to a human-flight spacecraft. For example, the X-38 flight computer is commercial equipment currently used in aircraft and the flight software operating system is a commercial system already in use in many aerospace applications. The video equipment for the X-38 is existing equipment, some of which has already flown on the space shuttle for previous NASA experiments. The X-38's primary navigational equipment, the Inertial Navigation System/Global Positioning System, is a unit already in use on Navy fighters. The X-38 electromechanical actuators come from previous joint NASA, U.S. Air Force, and U.S. Navy research and development projects. Finally, an existing special coating developed by NASA will be used on the X-38 thermal tiles to make them more durable than those used on the space shuttles. The X-38 itself was an unpiloted lifting body designed at 80 percent of the size of a projected emergency crew return vehicle for the International Space Station, although two later versions were planned at 100 percent of the CRV size. The X-38 and the actual CRV are patterned after a lifting-body shape first employed in the Air Force-NASA X-24 lifting-body project in the early to mid-1970s. The current vehicle design is base lined with life support supplies for about nine hours of orbital free flight from the space station. It's landing will be fully automated with backup systems which allow the crew to control orientation in orbit, select a deorbit site, and steer the parafoil, if necessary. The X-38 vehicles (designated V131, V132, and V-131R) are 28.5 feet long, 14.5 feet wide, and weigh approximately 16,000 pounds on average. The vehicles have a nitrogen-gas-operated attitude control system and a bank of batteries for internal power. The actual CRV to be flown in space was expected to be 30 feet long. The X-38 project is a joint effort between the Johnson Space Center, Houston, Texas (JSC), Langley Research Center, Hampton, Virginia (LaRC) and Dryden Flight Research Center, Edwards, California (DFRC) with the program office located at JSC. A contract was awarded to Scaled Composites, Inc., Mojave, California, for construction of the X-38 test airframes. The first vehicle was delivered to the JSC in September 1996. The vehicle was fitted with avionics, computer systems and other hardware at Johnson. A second vehicle was delivered to JSC in December 1996. Flight research with the X-38 at Dryden began with an unpiloted captive-carry flight in which the vehicle remained attached to its future launch vehicle, Dryden's B-52 008. There were four captive flights in 1997 and three in 1998, plus the first drop test on March 12, 1998, using the parachutes and parafoil. Further captive and drop tests occurred in 1999. In March 2000 Vehicle 132 completed its third and final free flight in the highest, fastest, and longest X-38 flight to date. It was released at an altitude of 39,000 feet and flew freely for 45 seconds, reaching a speed of over 500 miles per hour before deploying its parachutes for a landing on Rogers Dry Lakebed. In the drop tests, the X-38 vehicles have been autonomous after airlaunch from the B-52. After they deploy the parafoil, they have remained autonomous, but there is also a manual mode with controls from the ground.
O'Keefe, Joan A; Robertson-Dick, Erin; Dunn, Emily J; Li, Yan; Deng, Youping; Fiutko, Amber N; Berry-Kravis, Elizabeth; Hall, Deborah A
2015-12-01
Fragile X-associated tremor/ataxia syndrome (FXTAS) results from a "premutation" size 55-200 CGG repeat expansion in the fragile X mental retardation 1 (FMR1) gene. Core motor features include cerebellar gait ataxia and kinetic tremor, resulting in progressive mobility disability. There are no published studies characterizing balance deficits in FMR1 premutation carriers with and without FXTAS using a battery of quantitative measures to test the sensory integration underlying postural control, automatic postural reflexes, and dynamic postural stability limits. Computerized dynamic posturography (CDP) and two performance-based balance measures were administered in 44 premutation carriers, 21 with FXTAS and 23 without FXTAS, and 42 healthy controls to compare balance and functional mobility between these groups. Relationships between FMR1 molecular variables, age, and sex and CDP scores were explored. FXTAS subjects demonstrated significantly lower scores on the sensory organization test (with greatest reductions in the vestibular control of balance), longer response latencies to balance perturbations, and reduced stability limits compared to controls. Premutation carriers without FXTAS also demonstrated significantly delayed response latencies and disrupted sensory weighting for balance control. Advancing age, male sex, increased CGG repeat size, and reduced X activation of the normal allele in premutation carrier women predicted balance dysfunction. These postural control deficits in carriers with and without FXTAS implicate dysfunctional cerebellar neural networks and may provide valuable outcome markers for tailored rehabilitative interventions. Our findings suggest that CDP may provide sensitive measures for early detection of postural control impairments in at-risk carriers and better characterize balance dysfunction and progression in FXTAS.
Phase control of Mn-based spinel films via pulsed laser deposition
Feng, Zhenxing; Chen, Xiao; Fister, Timothy T.; ...
2016-07-06
Phase transformations in battery cathode materials during electrochemical-insertion reactions lead to capacity fading and low cycle life. One solution is to keep the same phase of cathode materials during cation insertion-extraction processes. Here, we demonstrate a novel strategy to control the phase and composition of Mn-based spinel oxides for magnesium-ion battery applications through the growth of thin films on lattice-matched substrates using pulsed laser deposition. Materials at two extreme conditions are considered: fully discharged cathode MgMn 2O 4 and fully charged cathode Mn 2O 4. The tetragonal MgMn 2O 4 (MMO) phase is obtained on MgAl 2O 4 substrates, whilemore » the cubic MMO phase is obtained on MgO substrates. Similarly, growth of the empty Mn 2O 4 spinel in the cubic phase is obtained on an MgO substrate. These results demonstrate the ability to control separately the phase of spinel thin films (e.g., tetragonal vs. cubic MMO) at nominally fixed composition, and to maintain a fixed (cubic) phase while varying its composition (MgxMn 2O 4, for x = 0, 1). As a result, this capability provides a novel route to gain insights into the operation of battery electrodes for energy storage applications.« less
Phase control of Mn-based spinel films via pulsed laser deposition
DOE Office of Scientific and Technical Information (OSTI.GOV)
Feng, Zhenxing; Chen, Xiao; Fister, Timothy T.
Phase transformations in battery cathode materials during electrochemical-insertion reactions lead to capacity fading and low cycle life. One solution is to keep the same phase of cathode materials during cation insertion-extraction processes. Here, we demonstrate a novel strategy to control the phase and composition of Mn-based spinel oxides for magnesium-ion battery applications through the growth of thin films on lattice-matched substrates using pulsed laser deposition. Materials at two extreme conditions are considered: fully discharged cathode MgMn 2O 4 and fully charged cathode Mn 2O 4. The tetragonal MgMn 2O 4 (MMO) phase is obtained on MgAl 2O 4 substrates, whilemore » the cubic MMO phase is obtained on MgO substrates. Similarly, growth of the empty Mn 2O 4 spinel in the cubic phase is obtained on an MgO substrate. These results demonstrate the ability to control separately the phase of spinel thin films (e.g., tetragonal vs. cubic MMO) at nominally fixed composition, and to maintain a fixed (cubic) phase while varying its composition (MgxMn 2O 4, for x = 0, 1). As a result, this capability provides a novel route to gain insights into the operation of battery electrodes for energy storage applications.« less
1990-05-01
L0341 K ISOLATE MALFUNCTIONS TO DIRECTIONAL COUPLERS - 6 L0436 A REMOVE OR REPLACE TWTS - 6 M0443 A ALIGN DELAY EQUALIZER COMPONENTS - 6 M0447 A ALIGN...CONTROLS - 6 L0390 A PERFORM OPERATIONAL TESTS ON RECEIVER TRANSMITTER CONTROLS - 6 LO0O1 A PERFORM PHIS ON TWT SHF TRANSMITTERS - 6 L0410 A REMOVE OR...REPLACE DIRECTIONAL COUPLERS - 6 L0420 A REMOVE OR REPLACE LINE VOLTAGE REGULATORS - 6 L0435 A REMOVE OR REPLACE TWT SHF TRANSMITTERS - 6 L0436 A
Programming in a proposed 9X distributed Ada
NASA Technical Reports Server (NTRS)
Waldrop, Raymond S.; Volz, Richard A.; Goldsack, Stephen J.
1990-01-01
The proposed Ada 9X constructs for distribution was studied. The goal was to select suitable test cases to help in the evaluation of the proposed constructs. The examples were to be considered according to the following requirements: real time operation; fault tolerance at several different levels; demonstration of both distributed and massively parallel operation; reflection of realistic NASA programs; illustration of the issues of configuration, compilation, linking, and loading; indications of the consequences of using the proposed revisions for large scale programs; and coverage of the spectrum of communication patterns such as predictable, bursty, small and large messages. The first month was spent identifying possible examples and judging their suitability for the project.
The JPL telerobot operator control station. Part 2: Software
NASA Technical Reports Server (NTRS)
Kan, Edwin P.; Landell, B. Patrick; Oxenberg, Sheldon; Morimoto, Carl
1989-01-01
The Operator Control Station of the Jet Propulsion Laboratory (JPL)/NASA Telerobot Demonstrator System provides the man-machine interface between the operator and the system. It provides all the hardware and software for accepting human input for the direct and indirect (supervised) manipulation of the robot arms and tools for task execution. Hardware and software are also provided for the display and feedback of information and control data for the operator's consumption and interaction with the task being executed. The software design of the operator control system is discussed.
NASA Technical Reports Server (NTRS)
Ivancic, William; Stewart, Dave; Shell, Dan; Wood, Lloyd; Paulsen, Phil; Jackson, Chris; Hodgson, Dave; Notham, James; Bean, Neville; Miller, Eric
2005-01-01
This report documents the design of network infrastructure to support operations demonstrating the concept of network-centric operations and command and control of space-based assets. These demonstrations showcase major elements of the Transformal Communication Architecture (TCA), using Internet Protocol (IP) technology. These demonstrations also rely on IP technology to perform the functions outlined in the Consultative Committee for Space Data Systems (CCSDS) Space Link Extension (SLE) document. A key element of these demonstrations was the ability to securely use networks and infrastructure owned and/or controlled by various parties. This is a sanitized technical report for public release. There is a companion report available to a limited audience. The companion report contains detailed networking addresses and other sensitive material and is available directly from William Ivancic at Glenn Research Center.
NASA Technical Reports Server (NTRS)
Callantine, Todd J.; Cabrall, Christopher; Kupfer, Michael; Omar, Faisal G.; Prevot, Thomas
2012-01-01
NASA?s Air Traffic Management Demonstration-1 (ATD-1) is a multi-year effort to demonstrate high-throughput, fuel-efficient arrivals at a major U.S. airport using NASA-developed scheduling automation, controller decision-support tools, and ADS-B-enabled Flight-Deck Interval Management (FIM) avionics. First-year accomplishments include the development of a concept of operations for managing scheduled arrivals flying Optimized Profile Descents with equipped aircraft conducting FIM operations, and the integration of laboratory prototypes of the core ATD-1 technologies. Following each integration phase, a human-in-the-loop simulation was conducted to evaluate and refine controller tools, procedures, and clearance phraseology. From a ground-side perspective, the results indicate the concept is viable and the operations are safe and acceptable. Additional training is required for smooth operations that yield notable benefits, particularly in the areas of FIM operations and clearance phraseology.
ASTERIA: Arcsecond Space Telescope Enabling Research in Astrophysics
NASA Astrophysics Data System (ADS)
Knapp, M.; Seager, S.; Smith, M. W.; Pong, C. M.
2017-12-01
ASTERIA (Arcsecond Space Telescope Enabling Research in Astrophysics) is a technology demonstration and opportunistic science mission to advance the state of the art in CubeSat capabilities for astrophysical measurements. The goal of ASTERIA is to achieve arcsecond-level line of sight pointing error and highly stable focal plane temperature control. These technologies will enable precision photometry, i.e. the careful measurement of stellar brightness over time. This in turn provides a way to study stellar activity, transiting exoplanets, and other astrophysical phenomena, both during the ASTERIA mission and in future CubeSat constellations. ASTERIA is a 6U CubeSat (roughly 10 x 20 x 30 cm, 12 kg) that will operate in low-Earth orbit. The payload consists of a lens and baffle assembly, a CMOS imager, and a two-axis piezoelectric positioning stage on which the focal plane is mounted. A set of commercial reaction wheels provides coarse attitude control. Fine pointing control is achieved by tracking a set of guide stars on the CMOS sensor and moving the piezoelectric stage to compensate for residual pointing errors. Precision thermal control is achieved by isolating the payload from the spacecraft bus, passively cooling the detector, and using trim heaters to perform small temperature corrections over the course of an observation. The ASTERIA project is a collaboration with MIT and is funded at JPL through the Phaeton Program for training early career employees. Flight hardware was delivered in June 2017, with launch expected in August 2017 and deployment targeted for October 2017.
MEMS analog light processing: an enabling technology for adaptive optical phase control
NASA Astrophysics Data System (ADS)
Gehner, Andreas; Wildenhain, Michael; Neumann, Hannes; Knobbe, Jens; Komenda, Ondrej
2006-01-01
Various applications in modern optics are demanding for Spatial Light Modulators (SLM) with a true analog light processing capability, e.g. the generation of arbitrary analog phase patterns for an adaptive optical phase control. For that purpose the Fraunhofer IPMS has developed a high-resolution MEMS Micro Mirror Array (MMA) with an integrated active-matrix CMOS address circuitry. The device provides 240 x 200 piston-type mirror elements with 40 μm pixel size, where each of them can be addressed and deflected independently at an 8bit height resolution with a vertical analog deflection range of up to 400 nm suitable for a 2pi phase modulation in the visible. Full user programmability and control is provided by a newly developed comfortable driver software for Windows XP based PCs supporting both a Graphical User Interface (GUI) for stand-alone operation with pre-defined data patterns as well as an open ActiveX programming interface for a direct data feed-through within a closed-loop environment. High-speed data communication is established by an IEEE1394a FireWire interface together with an electronic driving board performing the actual MMA programming and control at a maximum frame rate of up to 500 Hz. Successful application demonstrations have been given in eye aberration correction, coupling efficiency optimization into a monomode fiber, ultra-short laser pulse modulation and diffractive beam shaping. Besides a presentation of the basic device concept the paper will give an overview of the obtained results from these applications.
Pulse intensity characterization of the LCLS nanosecond double-bunch mode of operation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sun, Yanwen; Decker, Franz-Josef; Turner, James
The recent demonstration of the 'nanosecond double-bunch' operation mode,i.e.two X-ray pulses separated in time between 0.35 and hundreds of nanoseconds and by increments of 0.35 ns, offers new opportunities to investigate ultrafast dynamics in diverse systems of interest. However, in order to reach its full potential, this mode of operation requires the precise characterization of the intensity of each X-ray pulse within each pulse pair for any time separation. Here, a transmissive single-shot diagnostic that achieves this goal for time separations larger than 0.7 ns with a precision better than 5% is presented. Lastly, it also provides real-time monitoring feedbackmore » to help tune the accelerator parameters to deliver double pulse intensity distributions optimized for specific experimental goals.« less
Pulse intensity characterization of the LCLS nanosecond double-bunch mode of operation
Sun, Yanwen; Decker, Franz-Josef; Turner, James; ...
2018-03-27
The recent demonstration of the 'nanosecond double-bunch' operation mode,i.e.two X-ray pulses separated in time between 0.35 and hundreds of nanoseconds and by increments of 0.35 ns, offers new opportunities to investigate ultrafast dynamics in diverse systems of interest. However, in order to reach its full potential, this mode of operation requires the precise characterization of the intensity of each X-ray pulse within each pulse pair for any time separation. Here, a transmissive single-shot diagnostic that achieves this goal for time separations larger than 0.7 ns with a precision better than 5% is presented. Lastly, it also provides real-time monitoring feedbackmore » to help tune the accelerator parameters to deliver double pulse intensity distributions optimized for specific experimental goals.« less
Hu, Yong; Ju, Shao-Hua; Zhang, Yin-Jie; Xiong, Min; Xu, Shi-Jun; Ma, Yun-Tong; Zhong, Zhen-Dong
2014-05-01
To study the effect of Tongluo Xingnao effervescent tablets on learning and memory capacity and expression of Na(+)-K(+)-ATPase in hippocampus of rats with chronic cerebral ischemia-induced learning and memory dysfunction model. The 2-VO method was used to establish sd rat model learning and memory dysfunction induced by chronic cerebral ischemia. The 50 rats in the successfully established model were randomly divided into the model control group, the Dihydroergotoxine Mesylate tablets group (0.7 mg x kg(-1), Tongluo Xingnao effervescent tablets high dose (7.56 g x kg(-1)), middle dose (3.78 g x kg(-1)) and low dose (1.59 g x kg(-1)) groups and the sham operation group (n = 10) as the control group. The groups were orally given 10 ml x kg(-1) x d(-1) drugs for consecutively 90 days. On the 86th day, Morris water maze was adopted for them. On the 90th day, a leaning and memory capacity test was held. The brain tissues were fixed with 10% formaldehyde and observed for pathomorphism after routine slide preparation and staining. The expression of hippocampal Na(+)-K(+)-ATPase was detected with immunohistochemistry and image quantitative analysis. Compared with the model group, all of Tongluo Xingnao effervescent tablets groups showed significant decrease in the escape latency at the 5th day in the Morris water maze, and notable increase in the frequency of the first quadrant dwell, the frequency passing the escape platform and the frequency entering effective area (p < 0.05). According to the pathomorphological detection, the control group showed a significantly higher pathological score than the sham operation group (p < 0.01), the middle dose group showed a significantly lower pathological score than the model group (p < 0.05). According to the immunohistochemistical detection, the model control group showed a remarkably lower mean OD value of Na(+)-K(+)-ATPase than the sham operation group (p < 0.05), high and middle dose groups showed a significantly higher mean od value than the model control group (p < 0.01). Tongluo Xingnao effervescent tablets can improve the learning and memory capacity, reduce pathological changes of hippocampal tissues of rats with chronic cerebral ischemia-induced learning and memory dysfunction model, and promote the expression of Na(+)-K(+)-ATPase in hippocampus.
Flight control system design factors for applying automated testing techniques
NASA Technical Reports Server (NTRS)
Sitz, Joel R.; Vernon, Todd H.
1990-01-01
Automated validation of flight-critical embedded systems is being done at ARC Dryden Flight Research Facility. The automated testing techniques are being used to perform closed-loop validation of man-rated flight control systems. The principal design features and operational experiences of the X-29 forward-swept-wing aircraft and F-18 High Alpha Research Vehicle (HARV) automated test systems are discussed. Operationally applying automated testing techniques has accentuated flight control system features that either help or hinder the application of these techniques. The paper also discusses flight control system features which foster the use of automated testing techniques.
Millimeter scale robots for the nanofactory
NASA Astrophysics Data System (ADS)
Murthy, Rakesh
The top down approach is a commonly employed miniaturization pathway into micro and nanomanufacturing. Its popularity is due to the fact that it adapts traditionally engineered macro scale positioning, manipulation and processing technology with micro and nano scale precision and part sizes. However, state of the art top down systems such as the Atomic Force Microscope (AFM) span four to five orders of magnitude larger than the parts being handled. This dissertation addresses the need for creating millimeter size robotic positioning technology that closes the size gap between equipment and part sizes. Such microrobot manufacturing methodology comprising of micro component-level design, fabrication and high yield assembly, system-level packaging, modeling, precision evaluation and control is presented and exemplified using two classes of microrobots. Both microrobots incorporate Micro Electro Mechanical Systems (MEMS) to combine high precision and low foot-print. The first microrobot type, the "ARRIpede" is a multi legged autonomous crawler, and is designed to operate as a mobile unit enabling parts transfer in a nanoassembly environment. An embodiment of this microrobot is demonstrated for planar motions with three degrees of freedom (XYtheta). The microrobot consists of a MEMS die "belly" spanning 10mm x 10mm x 1mm with in-plane electrothermal actuators and vertically assembled legs, and an electronic "backpack" spanning 15mmx15mmx10mm to generate a leg gait sequence. By incorporating bulk micromachined parts and precise epoxy dispensing at the assembled leg joint, the microrobot has a high payload bearing capacity (at least 9g). Simulations with a nonholonomic robot predict microcrawler velocities of a few mm/s under realistic assumptions. The open loop crawling velocity is experimentally characterized for various actuator frequencies and a close match with simulations is observed. A Linear Quadratic Regulator (LQR) based controller consisting of a high magnification camera and a laser displacement sensor for feedback is implemented. The open/closed loop positioning repeatabilities are evaluated and compared. The second micro robot called the "AFAM" (Articulated Four Axes Micro Robot) is a fixed base articulated design targeting micro and nano scale manipulation and probing applications. An embodiment of this microrobot is constructed incorporating four degrees of freedom (X, Y, Pitch and Yaw), occupying a total volume of 3mm x 2mm x 1mm, and operating within a workspace envelope of 50mum x 50mum x 75mum. This is by far the largest operating envelope of any other independent MEMS positioner with non-planar dexterity. A cable based transmission and motion amplification mechanism is designed to achieve the pitch and yaw degrees of freedom. The de-coupled motion of the microrobot is achieved by kinematic identification of the Jacobian and using a 3D flexure based kinematic model of the microrobot. By using the derived kinematics, the microrobot is driven to create nanoindents on a polymer surface. The end-effector positioning accuracy, repeatability and resolution are characterized using the nanoindents.
40 CFR 63.5715 - What operating limits must I meet?
Code of Federal Regulations, 2010 CFR
2010-07-01
... (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES National Emission Standards for Hazardous Air Pollutants for Boat Manufacturing Demonstrating Compliance for Open Molding Operations Controlled by Add-on Control Devices § 63.5715 What operating limits must I meet? (a) For open...
Ares I-X Flight Test Development Challenges and Success Factors
NASA Technical Reports Server (NTRS)
Askins, Bruce; Davis, Steve; Olsen, Ronald; Taylor, James
2010-01-01
The NASA Constellation Program's Ares I-X rocket launched successfully on October 28, 2009 collecting valuable data and providing risk reduction for the Ares I project. The Ares I-X mission was formulated and implemented in less than four years commencing with the Exploration Systems Architecture Study in 2005. The test configuration was founded upon assets and processes from other rocket programs including Space Shuttle, Atlas, and Peacekeeper. For example, the test vehicle's propulsion element was a Shuttle Solid Rocket Motor. The Ares I-X rocket comprised a motor assembly, mass and outer mold line simulators of the Ares I Upper Stage, Orion Spacecraft and Launch Abort System, a roll control system, avionics, and other miscellaneous components. The vehicle was 327 feet tall and weighed approximately 1,800,000 pounds. During flight the rocket reached a maximum speed of Mach 4.8 and an altitude of 150,000 feet. The vehicle demonstrated staging at 130,000 feet, tested parachutes for recovery of the motor, and utilized approximately 900 sensors for data collection. Developing a new launch system and preparing for a safe flight presented many challenges. Specific challenges included designing a system to withstand the environments, manufacturing large structures, and re-qualifying heritage hardware. These and other challenges, if not mitigated, may have resulted in test cancellation. Ares I-X succeeded because the mission was founded on carefully derived objectives, led by decisive and flexible management, implemented by an exceptionally talented and dedicated workforce, and supported by a thorough independent review team. Other major success factors include the use of proven heritage hardware, a robust System Integration Laboratory, multi-NASA center and contractor team, concurrent operations, efficient vehicle assembly, effective risk management, and decentralized element development with a centralized control board. Ares I-X was a technically complex test that required creative thinking, risk taking, and a passion to succeed.
2009-10-26
NASA Ares I-X Assistant Launch Director Pete Nickolenko, left, and NASA Ares I-X Launch Director Ed Mango monitor the launch countdown from Firing Room One of the Launch Control Center (LCC) at the Kennedy Space Center during the planned launch of the Ares I-X rocket from pad 39b at the Kennedy Space Center in Cape Canaveral, Fla., Tuesday, Oct. 27, 2009. The flight test of Ares I-X will provide NASA with an early opportunity to test and prove flight characteristics, hardware, facilities and ground operations associated with the Ares I. Photo Credit: (NASA/Bill Ingalls)
2009-10-27
NASA Ares I-X Launch Director Ed Mango, left, laughs as NASA Ares I-X Assistant Launch Director Pete Nickolenko looks out the window of Firing Room One of the Launch Control Center (LCC) at the Kennedy Space Center prior to the launch of the Ares I-X rocket from pad 39b at the Kennedy Space Center in Cape Canaveral, Fla., Wednesday, Oct. 28, 2009. The flight test of Ares I-X will provide NASA with an early opportunity to test and prove flight characteristics, hardware, facilities and ground operations associated with the Ares I. Photo Credit: (NASA/Bill Ingalls)
NASA Astrophysics Data System (ADS)
Lee, Junghyun; Kim, Heewon; Chung, Hyun; Kim, Haedong; Choi, Sujin; Jung, Okchul; Chung, Daewon; Ko, Kwanghee
2018-04-01
In this paper, we propose a method that uses a genetic algorithm for the dynamic schedule optimization of imaging missions for multiple satellites and ground systems. In particular, the visibility conflicts of communication and mission operation using satellite resources (electric power and onboard memory) are integrated in sequence. Resource consumption and restoration are considered in the optimization process. Image acquisition is an essential part of satellite missions and is performed via a series of subtasks such as command uplink, image capturing, image storing, and image downlink. An objective function for optimization is designed to maximize the usability by considering the following components: user-assigned priority, resource consumption, and image-acquisition time. For the simulation, a series of hypothetical imaging missions are allocated to a multi-satellite control system comprising five satellites and three ground stations having S- and X-band antennas. To demonstrate the performance of the proposed method, simulations are performed via three operation modes: general, commercial, and tactical.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Morey, W.W.
1988-12-01
This report summarizes the development and field testing of a combustor viewing probe (CVP) as a flame diagnostic monitor for utility gas turbine engines. The prototype system is capable of providing a visual record of combustor flame images, recording flame spectral data, analyzing image and spectral data, and diagnosing certain engine malfunctions. The system should provide useful diagnostic information to utility plant operators, and reduce maintenance costs. The field tests demonstrated the ability of the CVP to monitor combustor flame condition and to relate changes in the engine operation with variations in the flame signature. Engine light off, run upmore » to full speed, the addition of load, and the effect of water injection for NO/sub x/ control could easily be identified on the video monitor. The viewing probe was also valuable in identifying hard startups and shutdowns, as well as transient effects that can seriously harm the engine. 11 refs.« less
Air Traffic Management Technology Demonstration-1 Concept of Operations (ATD-1 ConOps), Version 2.0
NASA Technical Reports Server (NTRS)
Baxley, Brian T.; Johnson, William C.; Swenson, Harry N.; Robinson, John E.; Prevot, Tom; Callantine, Todd J.; Scardina, John; Greene, Michael
2013-01-01
This document is an update to the operations and procedures envisioned for NASA s Air Traffic Management (ATM) Technology Demonstration #1 (ATD-1). The ATD-1 Concept of Operations (ConOps) integrates three NASA technologies to achieve high throughput, fuel-efficient arrival operations into busy terminal airspace. They are Traffic Management Advisor with Terminal Metering (TMA-TM) for precise time-based schedules to the runway and points within the terminal area, Controller-Managed Spacing (CMS) decision support tools for terminal controllers to better manage aircraft delay using speed control, and Flight deck Interval Management (FIM) avionics and flight crew procedures to conduct airborne spacing operations. The ATD-1 concept provides de-conflicted and efficient operations of multiple arrival streams of aircraft, passing through multiple merge points, from top-of-descent (TOD) to the Final Approach Fix. These arrival streams are Optimized Profile Descents (OPDs) from en route altitude to the runway, using primarily speed control to maintain separation and schedule. The ATD-1 project is currently addressing the challenges of integrating the three technologies, and their implantation into an operational environment. The ATD-1 goals include increasing the throughput of high-density airports, reducing controller workload, increasing efficiency of arrival operations and the frequency of trajectory-based operations, and promoting aircraft ADS-B equipage.
Pompidor, Guillaume; Dworkowski, Florian S. N.; Thominet, Vincent; Schulze-Briese, Clemens; Fuchs, Martin R.
2013-01-01
The combination of X-ray diffraction experiments with optical methods such as Raman, UV/Vis absorption and fluorescence spectroscopy greatly enhances and complements the specificity of the obtained information. The upgraded version of the in situ on-axis micro-spectrophotometer, MS2, at the macromolecular crystallography beamline X10SA of the Swiss Light Source is presented. The instrument newly supports Raman and resonance Raman spectroscopy, in addition to the previously available UV/Vis absorption and fluorescence modes. With the recent upgrades of the spectral bandwidth, instrument stability, detection efficiency and control software, the application range of the instrument and its ease of operation were greatly improved. Its on-axis geometry with collinear X-ray and optical axes to ensure optimal control of the overlap of sample volumes probed by each technique is still unique amongst comparable facilities worldwide and the instrument has now been in general user operation for over two years. PMID:23955041
Pompidor, Guillaume; Dworkowski, Florian S N; Thominet, Vincent; Schulze-Briese, Clemens; Fuchs, Martin R
2013-09-01
The combination of X-ray diffraction experiments with optical methods such as Raman, UV/Vis absorption and fluorescence spectroscopy greatly enhances and complements the specificity of the obtained information. The upgraded version of the in situ on-axis micro-spectrophotometer, MS2, at the macromolecular crystallography beamline X10SA of the Swiss Light Source is presented. The instrument newly supports Raman and resonance Raman spectroscopy, in addition to the previously available UV/Vis absorption and fluorescence modes. With the recent upgrades of the spectral bandwidth, instrument stability, detection efficiency and control software, the application range of the instrument and its ease of operation were greatly improved. Its on-axis geometry with collinear X-ray and optical axes to ensure optimal control of the overlap of sample volumes probed by each technique is still unique amongst comparable facilities worldwide and the instrument has now been in general user operation for over two years.
Construction continues on the RLV complex at the Shuttle Landing Facility
NASA Technical Reports Server (NTRS)
1999-01-01
At the construction site of the Reusable Launch Vehicle (RLV) complex at KSC, workers take measurements for one of the buildings. Located near the Shuttle Landing Facility, the complex will include facilities for related ground support equipment and administrative/ technical support. It will be available to accommodate the Space Shuttle; the X-34 RLV technology demonstrator; the L-1011 carrier aircraft for Pegasus and X-34; and other RLV and X-vehicle programs. The complex is jointly funded by the Spaceport Florida Authority, NASA's Space Shuttle Program and KSC. The facility will be operational in early 2000.
Construction continues on the RLV complex at the Shuttle Landing Facility
NASA Technical Reports Server (NTRS)
1999-01-01
At the construction site of the Reusable Launch Vehicle (RLV) complex at KSC, a worker takes a measurement. Located near the Shuttle Landing Facility, the complex will include facilities for related ground support equipment and administrative/ technical support. It will be available to accommodate the Space Shuttle; the X-34 RLV technology demonstrator; the L-1011 carrier aircraft for Pegasus and X-34; and other RLV and X-vehicle programs. The complex is jointly funded by the Spaceport Florida Authority, NASA's Space Shuttle Program and KSC. The facility will be operational in early 2000.
1999-10-29
The first roof panels are placed on the multi-purpose hangar at the site of the $8 million Reusable Launch Vehicle (RLV) Support Complex at Kennedy Space Center. The RLV complex, which includes the hangar and a building for related ground support equipment and administrative/technical support, will be available to accommodate the Space Shuttle; the X-34 RLV technology demonstrator; the L-1011 carrier aircraft for Pegasus and X-34; and other RLV and X-vehicle programs. The complex is jointly funded by the Spaceport Florida Authority, NASA's Space Shuttle Program and KSC. The facility will be operational in early 2000
1999-10-29
Work continues on construction of the multi-purpose hangar at the site of the $8 million Reusable Launch Vehicle (RLV) Support Complex at Kennedy Space Center. In the background can be seen the new construction for the building that will house related ground support equipment and administrative/technical support. The RLV complex will be available to accommodate the Space Shuttle; the X-34 RLV technology demonstrator; the L-1011 carrier aircraft for Pegasus and X-34; and other RLV and X-vehicle programs. The complex is jointly funded by the Spaceport Florida Authority, NASA's Space Shuttle Program and KSC. The facility will be operational in early 2000
1999-10-29
Workers place the first roof panels on the multi-purpose hangar at the site of the $8 million Reusable Launch Vehicle (RLV) Support Complex at Kennedy Space Center. The RLV complex, which includes the hangar and a building for related ground support equipment and administrative/technical support, will be available to accommodate the Space Shuttle; the X-34 RLV technology demonstrator; the L-1011 carrier aircraft for Pegasus and X-34; and other RLV and X-vehicle programs. The complex is jointly funded by the Spaceport Florida Authority, NASA's Space Shuttle Program and KSC. The facility will be operational in early 2000
Soufli, Regina; Fernandez-Perea, Monica; Baker, Sherry L.; ...
2012-04-18
This article discusses the development and calibration of the x-ray reflective and diffractive elements for the Soft X-ray Materials Science (SXR) beamline of the Linac Coherent Light Source (LCLS) free-electron laser (FEL), designed for operation in the 500 – 2000 eV region. The surface topography of three Si mirror substrates and two Si diffraction grating substrates was examined by atomic force microscopy (AFM) and optical profilometry. The figure of the mirror substrates was also verified via surface slope measurements with a long trace profiler. A boron carbide (B 4C) coating especially optimized for the LCLS FEL conditions was deposited onmore » all SXR mirrors and gratings. Coating thickness uniformity of 0.14 nm root mean square (rms) across clear apertures extending to 205 mm length was demonstrated for all elements, as required to preserve the coherent wavefront of the LCLS source. The reflective performance of the mirrors and the diffraction efficiency of the gratings were calibrated at beamline 6.3.2 at the Advanced Light Source synchrotron. To verify the integrity of the nanometer-scale grating structure, the grating topography was examined by AFM before and after coating. This is to our knowledge the first time B 4C-coated diffraction gratings are demonstrated for operation in the soft x-ray region.« less
Long-wavelength infrared (LWIR) quantum-dot infrared photodetector (QDIP) focal plane array
NASA Astrophysics Data System (ADS)
Gunapala, S. D.; Bandara, S. V.; Hill, C. J.; Ting, D. Z.; Liu, J. K.; Rafol, S. B.; Blazejewski, E. R.; Mumolo, J. M.; Keo, S. A.; Krishna, S.; Chang, Y. C.; Shott, C. A.
2006-05-01
We have exploited the artificial atomlike properties of epitaxially self-assembled quantum dots for the development of high operating temperature long wavelength infrared (LWIR) focal plane arrays. Quantum dots are nanometer-scale islands that form spontaneously on a semiconductor substrate due to lattice mismatch. QDIPs are expected to outperform quantum well infrared detectors (QWIPs) and are expected to offer significant advantages over II-VI material based focal plane arrays. QDIPs are fabricated using robust wide bandgap III-V materials which are well suited to the production of highly uniform LWIR arrays. We have used molecular beam epitaxy (MBE) technology to grow multi-layer LWIR quantum dot structures based on the InAs/InGaAs/GaAs material system. JPL is building on its significant QWIP experience and is basically building a Dot-in-the-Well (DWELL) device design by embedding InAs quantum dots in a QWIP structure. This hybrid quantum dot/quantum well device offers additional control in wavelength tuning via control of dot-size and/or quantum well sizes. In addition the quantum wells can trap electrons and aide in ground state refilling. Recent measurements have shown a 10 times higher photoconductive gain than the typical QWIP device, which indirectly confirms the lower relaxation rate of excited electrons (photon bottleneck) in QDIPs. Subsequent material and device improvements have demonstrated an absorption quantum efficiency (QE) of ~ 3%. Dot-in-the-well (DWELL) QDIPs were also experimentally shown to absorb both 45o and normally incident light. Thus we have employed a reflection grating structure to further enhance the quantum efficiency. JPL has demonstrated wavelength control by progressively growing material and fabricating devices structures that have continuously increased in LWIR response. The most recent devices exhibit peak responsivity out to 8.1 microns. Peak detectivity of the 8.1μm devices has reached ~ 1 x 1010 Jones at 77 K. Furthermore, we have fabricated the first long-wavelength 640x512 pixels QDIP focal plane array. This QDIP focal plane array has produced excellent infrared imagery with noise equivalent temperature difference of 40 mK at 60K operating temperature. In addition, we have managed to increase the quantum efficiency of these devices from 0.1% (according to the data published in literature) to 20% in discrete devices. This is a factor of 200 increase in quantum efficiency. With these excellent results, for the first time QDIP performance has surpassed the QWIP performance. Our goal is to operate these long-wavelength detectors at much higher operating temperature than 77K, which can be passively achieved in space. This will be a huge leap in high performance infrared detectors specifically applicable to space science instruments.
Long-Wavelength Infrared (LWIR) Quantum Dot Infrared Photodetector (QDIP) Focal Plane Array
NASA Technical Reports Server (NTRS)
Gunapala, Sarath D.; Bandara, S. V.; Liu, J. K.; Hill, C. J.; Rafol, S. B.; Mumolo, J. M.; Shott, C. A.
2006-01-01
We have exploited the artificial atomlike properties of epitaxially self-assembled quantum dots for the development of high operating temperature long wavelength infrared (LWIR) focal plane arrays. Quantum dots are nanometer-scale islands that form spontaneously on a semiconductor substrate due to lattice mismatch. QDIPs are expected to outperform quantum well infrared detectors (QWIPs) and are expected to offer significant advantages over II-VI material based focal plane arrays. QDIPs are fabricated using robust wide bandgap III-V materials which are well suited to the production of highly uniform LWIR arrays. We have used molecular beam epitaxy (MBE) technology to grow multi-layer LWIR quantum dot structures based on the InAs/InGaAs/GaAs material system. JPL is building on its significant QWIP experience and is basically building a Dot-in-the-Well (DWELL) device design by embedding InAs quantum dots in a QWIP structure. This hybrid quantum dot/quantum well device offers additional control in wavelength tuning via control of dot-size and/or quantum well sizes. In addition the quantum wells can trap electrons and aide in ground state refilling. Recent measurements have shown a 10 times higher photoconductive gain than the typical QWIP device, which indirectly confirms the lower relaxation rate of excited electrons (photon bottleneck) in QDPs. Subsequent material and device improvements have demonstrated an absorption quantum efficiency (QE) of approx. 3%. Dot-in-the-well (DWELL) QDIPs were also experimentally shown to absorb both 45 deg. and normally incident light. Thus we have employed a reflection grating structure to further enhance the quantum efficiency. JPL has demonstrated wavelength control by progressively growing material and fabricating devices structures that have continuously increased in LWIR response. The most recent devices exhibit peak responsivity out to 8.1 microns. Peak detectivity of the 8.1 micrometer devices has reached approx. 1 x 10(exp 10) Jones at 77 K. Furthermore, we have fabricated the first long-wavelength 640x512 pixels QDP focal plane array. This QDIP focal plane may has produced excellent infrared imagery with noise equivalent temperature difference of 40 mK at 60K operating temperature. In addition, we have managed to increase the quantum efficiency of these devices from 0.1% (according to the data published in literature) to 20% in discrete devices. This is a factor of 200 increase in quantum efficiency. With these excellent results, for the first time QDIP performance has surpassed the QWIP performance. Our goal is to operate these long-wavelength detectors at much higher operating temperature than 77K which can be passively achieved in space. This will be a huge leap in high performance infrared detectors specifically applicable to space science instruments.
Cryogen-free operation of the Soft X-ray Spectrometer instrument
NASA Astrophysics Data System (ADS)
Sneiderman, Gary A.; Shirron, Peter J.; Fujimoto, Ryuichi; Bialas, Thomas G.; Boyce, Kevin R.; Chiao, Meng P.; DiPirro, Michael J.; Eckart, Megan E.; Hartz, Leslie; Ishisaki, Yoshitaka; Kelley, Richard L.; Kilbourne, Caroline A.; Masters, Candace; McCammon, Dan; Mitsuda, Kazuhisa; Noda, Hirofumi; Porter, Frederick S.; Szymkowiak, Andrew E.; Takei, Yoh; Tsujimoto, Masahiro; Yoshida, Seiji
2016-07-01
The Soft X-ray Spectrometer (SXS) is the first space-based instrument to implement redundancy in the operation of a sub-Kelvin refrigerator. The SXS cryogenic system consists of a superfluid helium tank and a combination of Stirling and Joule-Thompson (JT) cryocoolers that support the operation of a 3-stage adiabatic demagnetization refrigerator (ADR). When liquid helium is present, the x-ray microcalorimeter detectors are cooled to their 50 mK operating temperature by two ADR stages, which reject their heat directly to the liquid at 1.1 K. When the helium is depleted, all three ADR stages are used to accomplish detector cooling while rejecting heat to the JT cooler operating at 4.5 K. Compared to the simpler helium mode operation, the cryogen-free mode achieves the same instrument performance by controlling the active cooling devices within the cooling system differently. These include the three ADR stages and four active heat switches, provided by NASA, and five cryocoolers, provided by JAXA. Development and verification details of this capability are presented within this paper and offer valuable insights into the challenges, successes, and lessons that can benefit other missions, particularly those employing cryogen-free cooling systems.
SEXTANT - Station Explorer for X-ray Timing and Navigation Technology
NASA Technical Reports Server (NTRS)
Mitchell, Jason W.; Hasouneh, Munther Abdel Hamid; Winternitz, Luke M. B.; Valdez, Jennifer E.; Price, Samuel R.; Semper, Sean R.; Yu, Wayne H.; Arzoumanian, Zaven; Ray, Paul S.; Wood, Kent S.;
2015-01-01
The Station Explorer for X-ray Timing and Navigation Technology (SEXTANT) is a technology demonstration enhancement to the Neutron-star Interior Composition Explorer (NICER) mission, which is scheduled to launch in late 2016 and will be hosted as an externally attached payload on the International Space Station (ISS) via the ExPRESS Logistics Carrier (ELC). During NICER's 18-month baseline science mission to understand ultra-dense matter though observations of neutron stars in the soft X-ray band, SEXTANT will, for the first-time, demonstrate real-time, on-board X-ray pulsar navigation, which is a significant milestone in the quest to establish a GPS-like navigation capability that will be available throughout our Solar System and beyond. Along with NICER, SEXTANT has proceeded through Phase B, Mission Definition, and received numerous refinements in concept of operation, algorithms, flight software, ground system, and ground test capability. NICER/SEXTANT's Phase B work culminated in NASA's confirmation of NICER to Phase C, Design and Development, in March 2014. Recently, NICER/SEXTANT successfully passed its Critical Design Review and SEXTANT received continuation approval in September 2014. In this paper, we describe the X-ray pulsar navigation concept and provide a brief history of previous work, and then summarize the SEXTANT technology demonstration objective, hardware and software components, and development to date.
2001-11-13
North and West-facing facades of the 8x6 Supersonic Wind Tunnel in the early morning light. Caption: In the early morning light, the strong geometric lines behind the soft pine trees caught the eye of a photographer at Glenn Research Center. Behind the commanding facade lies the 8- by 6-Foot Supersonic Wind Tunnel (8x6 SWT), an atmospheric tunnel with perforated stainless steel walls that provide boundary control during transonic operations. It is NASA's only transonic propulsion wind tunnel. http://facilities.grc.nasa.gov/8x6/8x6_quick.html