WorldWideScience
1

Fluidic programmer for nuclear engine application  

International Nuclear Information System (INIS)

... fluidic control devices performance reactor control systems space propulsion

2

Twenty First Century Space Propulsion Study Addendum  

Science.gov (United States)

... Fuels", Paper AIAA-91-2451, 27th AIAA/SAE/ASME ... to-surface ballistic missiles than space-based space-to ... an effective hit-to-kill weapon without the ...

1991-06-01

3

notes4.htm - NASA's History Office  

Science.gov (United States)

Subcommittee of the Joint Committee on Atomic Energy of the United States, Outer Space Propulsion by Nuclear Energy, hearings, 85th Cong., 2d sess., 22, ...

4

Space Images - NASA Jet Propulsion Laboratory  

Science.gov (United States)

Jan 18, 2011 ... The Radiation Assessment Detector, shown prior to its September 2010 ... This 360-degree panorama shows the vista from the location where ...

5

Attendees - MEPAG - NASA  

Science.gov (United States)

Barlow, Nadine Northern Arizona University, Flagstaff, AZ. 10. Barker, Don NASA Johnson Space Center, TX. 11. Beaty, David NASA Jet Propulsion Laboratory, ...

6

AIAA 98-3403 Evaluation of Propulsion Options for Interstellar ...  

Science.gov (United States)

require a major space-based infrastructure consisting of ..... gas (5 ppm of the He, 1.3 kg/year) or from weapons (15 kg/year). Because of the difficulty of ...

7

12th Symposium on Space Nuclear Power and Propulsion. Conference on Alternative Power from Space (APFS),Conference on Accelerator-Driven Transmutation Technologies and Applications (A-DTTA)  

International Nuclear Information System (INIS)

These proceedings represent papers presented at the 12th symposium on Space Nuclear Power and Propulsion held in Albuquerque, New Mexico. The symposium theme was ''commercialization and technology transfer''. The topics discussed include: wireless power transmission, solar power from space next generation spacecraft, space power electronics and power management, flight testing of components, manufacturing and processing of materials, nuclear propulsion, reactors and shielding and many others of interest to the scientific community representing industry, government and academic institutions. There were 163 papers presented at the conference and 60 have been abstracted for the Energy Science and Technology database.

1995-01-08

8

STS-94 - Johnson Space Center - NASA  

Science.gov (United States)

spacecraft and aircraft propulsion, and hazardous waste disposal. .... called lockers and two larger, standardized compartments called drawers. ..... ductile refractory metal used chiefly in nuclear reactors and chemical processing ...

9

STS-83 - Johnson Space Center - NASA  

Science.gov (United States)

Radiation Measurement in Crew Compartment. DTO 805: .... spacecraft and aircraft propulsion, and hazardous waste disposal. ...... combustion reactions in a turbulent chemical kinetic flow reactor using laser induced fluorescence and ...

10

In-Space Propulsion Program Advanced Sensor Project - NASA  

Science.gov (United States)

Aug 25, 2004 ... Current Developments in Future Planetary Probe Sensors: .... Data: Outgoing and incoming EIA RS-422 interface for serial data transmission (for electrical purposes only, .... Milos, et. al, Journal of Spacecraft & Rockets 1999 ...

11

BEACON eSpace at Jet Propulsion Laboratory: Estimating the Cost of ...  

Science.gov (United States)

Jan 22, 2011 ... dc.subject.other, Cost cost estimating budgets budget estimating ... dc.title, Estimating the Cost of Doing a Cost Estimate, en_US ...

12

A nuclear powered pulsed inductive plasma accelerator as a viable propulsion concept for advanced OTV space applications  

International Nuclear Information System (INIS)

An electric propulsion concept suitable for delivering heavy payloads from low earth orbit (LEO) to high energy earth orbit is proposed. The system consists of a number of pulsed inductive plasma thrusters powered by a 100 kWe space nuclear power system. The pulsed plasma thruster is a relatively simple electrodeless device. It also exhibits adequate conversion to thrust power in the desired I sub sp regime of 1500 to 3000 seconds for optimal payload transfer from low earth to high earth orbit. Because of these features and the fact that the nuclear power unit will be capable of delivering sustained high power levels throughout the duration of any given mission, the system presented appears to be a very promising propulsion candidate for advanced orbital transfer vehicle (OTV) applications. An OTV, which makes use of this propulsion system and which has been designed to lift a 9000-lb payload into ...

13

Nuclear propulsion systems for orbit transfer based on the particle bed reactor  

International Nuclear Information System (INIS)

The technology of nuclear direct propulsion orbit transfer systems based on the Particle Bed Reactor (PBR) is described. A 200 megawatt illustrative design is presented for LEO to GEO and other high #DELTA#V missions. The PBR-NOTV can be used in a one-way mode with the shuttle or an expendable launch vehicle, e.g., the Titan 34D7, or as a two-way reusable space tug. In the one-way mode, payload capacity is almost three times greater than that of chemical OTV's. PBR technology status is described and development needs outlined.

1987-01-12

14

Intersociety energy conversion engineering conference, 20th, Miami Beach, FL, August 18-23, 1985, Proceedings. Volumes 1, 2, and 3  

International Nuclear Information System (INIS)

Topics related to aerospace power are discussed, taking into account trends and issues of military space power systems technology, space station power system advanced development, the application and use of nuclear power for future spacecraft, the current status of advanced solar array technology development, the application of a parabolic trough concentrator to space station power needs, life test results of the Intelsat-V nickel-cadmium battery, and metal hydride hydrogen storage in nickel hydrogen batteries. Other subjects explored are concerned with alternative fuels, biomass energy, biomedical power, coal gasification, electric power cycles, and electric propulsion. Attention is given to an advanced terrestrial vehicle electric propulsion systems assessment, fuel cells as electric propulsion power plants, a sinewave synthesis for high efficiency dc-ac ...

1985-08-18

15

CRC handbook of NASA future missions and payloads  

Energy Technology Data Exchange (ETDEWEB)

The author presents a detailed and quantitative description of all of the programs, systems, sensors and experiments associated with the next 30 years of space endeavors by the National Aeronautics and Space Administration. Derived from the fifth issue of the NASA Space Systems Technology Model, the missions and payloads are categorized by applications area: solar system exploration, astrophysics, earth sciences, communications, space transportation and utilization of the space environment. Far-term missions are described as opportunity missions and landmark missions, for the distant future. Technology requirements are collected by discipline: power, propulsion, materials, structures, information systems, navigation, guidance and control. Payload technology requirements are organized by instrument sensing range. This information defines in quantitative terms, ...

1986-01-01

16

Power systems for space exploration  

Energy Technology Data Exchange (ETDEWEB)

The Outreach Program was designed to solicit creative ideas from academia, research institutions, private enterprises, and the general public and is intended to be helpful in defining promising technical areas and program paths for more detailed study. To the Outreach Program, a number of power system concepts were proposed. In conclusion, there are a number of advanced concepts for space power and propulsion sources that deserve study if we want to expand our ability to not only explore space, but to utilize it. Advanced nuclear concepts and power beaming concepts are two areas worthy of detailed assessments.

1992-01-01

17

Visions of tomorrow: a focus on national space transportation issues; Proceedings of the Twenty-fifth Goddard Memorial Symposium, Greenbelt, MD, Mar. 18-20, 1987  

Science.gov (United States)

The present conference on U.S. space transportation systems development discusses opportunities for aerospace students in prospective military, civil, industrial, and scientific programs, current strategic conceptualization and program planning for future U.S. space transportation, the DOD space transportation plan, NASA space transportation plans, medium launch vehicle and commercial space launch services, the capabilities and availability of foreign launch vehicles, and the role of commercial space launch systems. Also discussed are available upper stage systems, future space transportation needs for space science and applications, the trajectory analysis of a low lift/drag-aeroassisted orbit transfer vehicle, possible replacements for the Space Shuttle, LEO to GEO with combined ...

1987-01-01

18

A magneto-electric quantum wheel  

CERN Document Server

Here we show that self-propulsion in quantum vacuum may be achieved by rotating or aggregating magneto-electric nano-particles. The back-action follows from changes in momentum of electro-magnetic zero-point fluctuations, generated in magneto-electric materials. This effect may provide new tools for investigation of the quantum nature of our world. It might also serve in the future as a "quantum wheel" to correct satellite orientation in space.

2009-01-01

19

The nuclear option  

Energy Technology Data Exchange (ETDEWEB)

A development history and current status evaluation are presented for nuclear-thermal rocket propulsion systems applicable to interplanetary flight. While the most advanced current chemical rocket engines, such as the SSMEs of the Space Shuttle, produce specific impulses of the order of 450 secs, a nuclear-thermal rocket engine tested at Los Alamos in 1969 generated 845 secs; such specific impulse improvements could represent weeks or months of interplanetary travel time. Attention is given to the achievements of the historical Nuclear Engine for Rocket Vehicle Application, Helios, and Orion design programs, as well as to the current Vehicle for Interplanetary Space Transportation Applications, which is fusion-based.

1992-03-01

20

From Earth to Mars in 15 days with an americium-propelled space ship; De la terre a mars en 15 jours avec un vaisseau spatial propulse a l'americium  

Energy Technology Data Exchange (ETDEWEB)

This digest paper presents the theoretical project of a fission engine for space ship as imagined by Y. Ronen from the Ben-Gourion Univ. (Israel). In this engine, the combustion chamber is covered with metastable {sup 242}Am thin sheets. The fission reaction is triggered with a bombardment of neutrons and the fission fragments ionize a gas (hydrogen, for instance) which is overheated and ejected through the engine nozzle. (J.S.)

2002-01-01

21

An americium-fueled gas core nuclear rocket  

Energy Technology Data Exchange (ETDEWEB)

A gas core fission reactor that utilizes americium in place of uranium is examined for potential utilization as a nuclear rocket for space propulsion. The isomer [sup 242m]Am with a half life of 141 years is obtained from an (n, [gamma]) capture reaction with [sup 241]Am, and has the highest known thermal fission cross section. We consider a 7500 MW reactor, whose propulsion characteristics with [sup 235]U have already been established, and re-examine it using americium. We find that the same performance can be achieved at a comparable fuel density, and a radial size reduction (of both core and moderator/reflector) of about 70%.

1993-01-10

22

SERAPHIM: A propulsion technology for fast trains  

Energy Technology Data Exchange (ETDEWEB)

The Segmented Rail Phased Induction Motor (SERAPHIM) is a compact, pulsed linear induction motor (LIM) offering a unique capability for very high speed train propulsion. It uses technology developed for the Sandia coilgun, an electromagnetic launcher designed to accelerate projectiles to several kilometers per second. Both aluminum cylinders and plates were accelerated to a kilometer per second (Mach 3) by passing through a sequence of coils which were energized at the appropriate time. Although this technology was developed for ultra-high velocity, it can be readily adapted to train propulsion for which, at sea level, the power required to overcome air resistance limits the operational speed to a more modest 300 mph. Here, the geometry is reversed. The coils are on the vehicle and the ``projectiles`` are fixed along the roadbed. SERAPHIM operates not by embedding flux in a conductor, but by excluding it. In this propulsion ...

1995-06-01

23

Radio Frequency Plasma Applications for Space Propulsion  

Energy Technology Data Exchange (ETDEWEB)

Recent developments in solid-state radio frequency (RF) power technologies allow for the practical consideration of RF heated plasmas for space propulsion. These technologies permit the use of any electrical power source, de-couple the power and propellant sources, and allow for the effcient use of both the propellant mass and power. Effcient use of the propellant is obtained by expelling the rocket exhaust at the highest possible velocity, which can be orders of magnitude higher than those achieved in chemical rockets. Handling the hot plasma exhaust requires the use of magnetic nozzles, and the basic physics of ion detachment from the magnetic eld is discussed. The plasma can be generated by RF using helicon waves to heat electrons. Further direct heating of the ions helps to reduce the line radiation losses, and the magnetic geometry is tailored to allow ion cyclotron resonance heating. RF eld and ion trajectory calculations are presented to ...

1999-09-13

24

An historical perspective of the NERVA nuclear rocket engine technology program. Final Report  

Energy Technology Data Exchange (ETDEWEB)

Nuclear rocket research and development was initiated in the United States in 1955 and is still being pursued to a limited extent. The major technology emphasis occurred in the decade of the 1960s and was primarily associated with the Rover/NERVA Program where the technology for a nuclear rocket engine system for space application was developed and demonstrated. The NERVA (Nuclear Engine for Rocket Vehicle Application) technology developed twenty years ago provides a comprehensive and viable propulsion technology base that can be applied and will prove to be valuable for application to the NASA Space Exploration Initiative (SEI). This paper, which is historical in scope, provides an overview of the conduct of the NERVA Engine Program, its organization and management, development philosophy, the engine configuration, and significant accomplishments.

1991-07-01

25

A combined cycle engine test facility  

Energy Technology Data Exchange (ETDEWEB)

Rocket-Based Combined-Cycle (RBCC) engines intended for missiles and/or space launch applications incorporate features of rocket propulsion systems operating in concert with airbreathing engine cycles. Performance evaluation of these types of engines, which are intended to operate from static sea level take-off to supersonic cruise or accerlerate to orbit, requires ground test capabilities which integrate rocket component testing with airbreathing engine testing. A combined cycle engine test facility has been constructed in the General Applied Science Laboratories, Inc. (GASL) Aeropropulsion Test Laboratory to meet this requirement. The facility was designed to support the development of an innovative combined cycle engine concept which features a rocket based ramjet combustor. The test requirements included the ability to conduct tests in which the propulsive force was generated by rocket only, the ramjet only and ...

1995-09-01

26

New York City Transit Hybrid and CNG Transit Buses: Final Evaluation Results  

Energy Technology Data Exchange (ETDEWEB)

This report describes the evaluation results for new Orion VII buses at NYCT with CNG propulsion and new hybrid propulsion.

2006-11-01

27

Planetary protection protecting earth and planets against alien microbes  

International Nuclear Information System (INIS)

Protecting Earth and planets against the invasion of 'alien life forms' is not military science fiction, but it is the peaceful daily job of engineers and scientists of space agencies. 'Planetary Protection' is preventing microbial contamination of both the target planet and the Earth when sending robots on interplanetary space mission. It is important to preserve the 'natural' conditions of other planets and to not bring with robots 'earthly microbes' (forward contamination) when looking for 'spores of extra terrestrial life'. The Earth and its biosphere must be protected from potential extraterrestrial biological contamination when returning samples of other planets to the Earth (backward contamination). The NASA-Caltech Laboratory for Planetary Protection of Dr. Kasthuri Venkateswaran at the Jet Propulsion Laboratory (JPL) (California, USA) routinely monitors and characterizes the microbes of NASA spacecraft assembly ...

2006-04-01

28

Energy and Water Conservation  

Science.gov (United States)

Jet Propulsion Laboratory. California Institute of Technology. Pasadena, California. Energy and Water Conservation. Steve Rigdon. Facilities Energy Manager ...

29

BIOMAGNETIC RESPONSE OF SIMPLE BIOLOGICAL ...  

Science.gov (United States)

... Examples include magnetic forming tools, magnetic shielding, magnetohydrodynamic propulsion systems, and various magnetic containment ...

1970-01-01

30

ASPECTS OF PERFORMANCE EVALUATION OF WATERJET ...  

Science.gov (United States)

... Propulsive efficiency is equivalent to the product of thrust efficiency and the hull/waterjet interaction efficiency. ... t'waterjet pump Ktorque repeated ...

1967-10-01

31

Method for forming a bladder for fluid storage vessels  

Energy Technology Data Exchange (ETDEWEB)

A lightweight, low permeability liner for graphite epoxy composite compressed gas storage vessels. The liner is composed of polymers that may or may not be coated with a thin layer of a low permeability material, such as silver, gold, or aluminum, deposited on a thin polymeric layer or substrate which is formed into a closed bladder using torispherical or near torispherical end caps, with or without bosses therein, about which a high strength to weight material, such as graphite epoxy composite shell, is formed to withstand the storage pressure forces. The polymeric substrate may be laminated on one or both sides with additional layers of polymeric film. The liner may be formed to a desired configuration using a dissolvable mandrel or by inflation techniques and the edges of the film seamed by heat sealing. The liner may be utilized in most any type of gas storage system, and is particularly applicable for hydrogen, gas mixtures, and oxygen used for vehicles, fuel cells or regenerative ...

2000-01-01

32

Lightweight bladder lined pressure vessels  

Energy Technology Data Exchange (ETDEWEB)

A lightweight, low permeability liner for graphite epoxy composite compressed gas storage vessels. The liner is composed of polymers that may or may not be coated with a thin layer of a low permeability material, such as silver, gold, or aluminum, deposited on a thin polymeric layer or substrate which is formed into a closed bladder using torispherical or near torispherical end caps, with or without bosses therein, about which a high strength to weight material, such as graphite epoxy composite shell, is formed to withstand the storage pressure forces. The polymeric substrate may be laminated on one or both sides with additional layers of polymeric film. The liner may be formed to a desired configuration using a dissolvable mandrel or by inflation techniques and the edges of the film seamed by heat sealing. The liner may be utilized in most any type of gas storage system, and is particularly applicable for hydrogen, gas mixtures, and oxygen used for vehicles, fuel cells or regenerative ...

1998-01-01

33

Optimization of the availability-safety pair for propulsion boilers; Optimisation du couple, disponibilite - surete pour les chaufferies de propulsion  

Energy Technology Data Exchange (ETDEWEB)

The relations between nuclear energy availability and nuclear plant safety are analyzed in the particular cases of naval propulsion nuclear boilers (aircraft carriers, submarines): safety objectives, present and potential risk analysis, optimization of the availability-safety couple, at the design stage and during operation (procedural rules related to the boiler state, real time decisions). 6 fig., 1 tab.

1994-12-31

34

Turbulence in Space Plasmas  

CERN Document Server

Turbulence in Space Plasmas

2009-01-01

35

space weather  

Wastenet

Title: space weather ... Subject: space weather ...Number 361 July 2010 Space Weather

36

Atmospheric environmental implications of propulsion systems  

Energy Technology Data Exchange (ETDEWEB)

Three independent studies have been conducted for assessing the impact of rocket launches on the earth`s environment. These studies have addressed issues of acid rain in the troposphere, ozone depletion in the stratosphere, toxicity of chemical rocket exhaust products, and the potential impact on global warming from carbon dioxide emissions from rocket launches. Local, regional, and global impact assessments were examined and compared with both natural sources and anthropogenic sources of known atmospheric pollutants with the following conclusions: (1) Neither solid nor liquid rocket launches have a significant impact on the earth`s global environment, and there is no real significant difference between the two. (2) Regional and local atmospheric impacts are more significant than global impacts, but quickly return to normal background conditions within a few hours after launch. And (3) vastly increased space launch activities equivalent to 50 U.S. ...

1995-03-01

37

View Record - NASA Jet Propulsion Laboratory  

Science.gov (United States)

Jan 13, 2011 ... This 360-degree mosaic of images from the navigation camera on ... The Radiation Assessment Detector, shown prior to its September 2010 ...

38

Propulsion and Power Rapid Response R&D Support ...  

Science.gov (United States)

... Results of the AXI5345-18 Motor, Jeti Spin 99 Controller and the APC 27 x 13 Propeller in use with a Linearized Fuel Cell Model Assuming Voc ...

2008-12-01

39

Profiles - NASA Jet Propulsion Laboratory  

Science.gov (United States)

Jun 30, 2003 ... He graduated from training with top honors and served as a parachute rigger and paratrooper for the 82nd airborne division at Fort Bragg, ...

40

NASAPerformance Report - NASA Technical Reports Server  

Science.gov (United States)

test bed (ADTT) tools technology. Glenn. Research. Center: Aircraft icing training video for regional and cor- porate pilots. Numerical propulsion ...

41

NASA Jet Propulsion Laboratory - Lecture series  

Science.gov (United States)

A Self-Powered Underwater Robot for Ocean Exploration and Beyond ... first unmanned underwater vehicle (UUV) that is completely powered by renewable energy . ...

42

NASA - Spitzer Sees Spider Web of Stars  

Science.gov (United States)

star formation. To either side of the center, a small bar of dust and gas is helping to fuel the new stars. NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the...

2011-07-20

43

NASA - A Cosmic Inkblot Test  

Science.gov (United States)

material may survive intact and mix back into interstellar gas clouds, helping to fuel the next generation of stars. NASA's Jet Propulsion Laboratory, Pasadena, Calif.,...

2011-08-10

44

Infrared Thermometer - NASA Spinoff  

Science.gov (United States)

May 1, 2011 ... Abstract: Diatek Corporation, San Diego, CA and the Jet Propulsion Lab developed the Diatek Model 7000 aural thermometer which weighs ...

45

E-11775 Cover set - Glenn Research Center - NASA  

Science.gov (United States)

be due to flow separation and reattachment, rather than transition. The analysis predicted a .... lations of Transonic Fan Performance," AGARD Propulsion ...

46

Bibliography of Papers on the WIND CFD Code  

Science.gov (United States)

Hamed, A. and A. Mohamed, "Assessment of Shock Induced Flow Separation and ...... AGARD Symposium on Combined Cycle Propulsion for Hypersonic Application, ...

47

Application of Synthetic Jets to Reduce Stator Flow Separation in a ...  

Science.gov (United States)

Surface pressure measurements at mid span indicate that flow separation begins near ..... Turbomachinery Flows, AGARD Propulsion Energetics Panel, 1998. ...

48

A Great Day to Go Flying  

Science.gov (United States)

but one test point on the flight cards was achieved before we hit our "bingo," or minimal fuel remaining, and we had to land. The radar was developed by NASA's Jet Propulsion...

2011-10-07

49

+ September 2006 - NASA Jet Propulsion Laboratory  

Science.gov (United States)

Post-drive imaging included 360-degree view by the navigation camera and .... Sol 938: Opportunity completed another assessment of the clarity of the sky. ...

50

Propulsion by tachyon beams  

Energy Technology Data Exchange (ETDEWEB)

A possibility of generating collimated beams of faster-than-light particles (tachyons) and using them for rocket propulsion is explored. The relativistic rocket equations are derived, and are solved for a single-stage rocket with constant mass flow rate, constant exhaust velocity and no coasting period. The features of these solutions for faster-than-light exhaust velocities are discussed. It is shown that a tachyon drive would not violate the first law of thermodynamics. However, as seen in the Galactic frame, it would violate the second law.

1989-07-01

51

Performance of catalysts for CO removal by methanation  

Energy Technology Data Exchange (ETDEWEB)

This report forms part of a joint study on a PEFC propulsion system for surface ships, summarized in a presentation to this Seminar, entitled {open_quotes}Study on a Polymer Electrolyte Fuel Cell (PEFC) Propulsion System for Surface Ships{close_quotes}, and which envisages application to a 1,500 DWT cargo vessel. The aspect treated here concerns an experiment in reducing by methanation to a level below 10 ppm the CO that is contained to around 1% in reformate gas.

1996-12-31

52

Nuclear Thermal Propulsion engine based on Particle Bed Reactor using light water steam as a propellant  

Energy Technology Data Exchange (ETDEWEB)

In this paper the possibility of configuring a water cooled Nuclear Thermal Propulsion (NTP) rocket, based on a Particle Bed Reactor (PBR) is investigated. This rocket will be used to operate on water obtained from near earth objects. The conclusions reached in this paper indicate that it is possible to configure a PBR based NTP rocket to operate on water and meet the mission requirements envisioned for it. No insurmountable technology issues have been identified.

1993-06-01

53

Independent effects of weight and mass on plantar flexor activity during walking: implications for their contributions to body support and forward propulsion  

UK PubMed Central (United Kingdom)

The ankle plantar flexor muscles, gastrocnemius (Gas) and soleus (Sol), have been shown to play important roles in providing body support and forward propulsion during human walking. However, there...Full Text Available

2008-08-01

54

In-Use Performance Comparison of Hybrid Electric, CNG, and Diesel Buses at New York City Transit  

Energy Technology Data Exchange (ETDEWEB)

The National Renewable Energy Laboratory (NREL) evaluated the performance of diesel, compressed natural gas (CNG), and hybrid electric (equipped with BAE Systems? HybriDrive propulsion system) transit buses at New York City Transit (NYCT). CNG, Gen I and Gen II hybrid electric propulsion systems were compared on fuel economy, maintenance and operating costs per mile, and reliability.

2008-06-01

55

On the Utility of Antiprotons as Drivers for Inertial Confinement Fusion  

Energy Technology Data Exchange (ETDEWEB)

By contrast to the large mass, complexity and recirculating power of conventional drivers for inertial confinement fusion (ICF), antiproton annihilation offers a specific energy of 90MJ/{micro}g and thus a unique form of energy packaging and delivery. In principle, antiproton drivers could provide a profound reduction in system mass for advanced space propulsion by ICF. We examine the physics underlying the use of antiprotons ({bar p}) to drive various classes of high-yield ICF targets by the methods of volumetric ignition, hotspot ignition and fast ignition. The useable fraction of annihilation deposition energy is determined for both {bar p}-driven ablative compression and {bar p}-driven fast ignition, in association with 0-D and 1-D target burn models. Thereby, we deduce scaling laws for the number of injected antiprotons required per capsule, together with timing and focal spot requirements. The kinetic energy of the injected antiproton ...

2003-10-20

56

Aerosol Properties Over the United Arab Emirates and Arabian Gulf from MISR Multi-angle Satellite Imaging  

Science.gov (United States)

The MISR instrument aboard NASA's Terra satellite participated in the UAE-2 campaign, August-October 2004. This campaign represented a unique opportunity to study the complex aerosol situation in the Arabian Gulf region, in the context of a first-rate collection of aircraft and surface-based instruments, giving us the opportunity to do some groundbreaking satellite aerosol validation work. We aimed (1) to validate MISR aerosol retrieval results for dust and pollution particles over dark and light surfaces, and (2) to contribute regional maps of aerosol optical thickness (AOT) and particle micro-physical properties, giving spatial context to the field-instrument measurements, and moving toward a satellite-based regional aerosol climatology. The validation effort benefited from the combination of an instrumented aircraft and a regional network of surface-based sun photometers. We obtained high-quality sub-orbital data coincident with MISR overpasses on three days: September 01, 10, and ...

2005-12-01

57

Fault detection and diagnosis of a gearbox in marine propulsion systems using bispectrum analysis and artificial neural networks  

British Library Electronic Table of Contents (United Kingdom)

A marine propulsion system is a very complicated system composed of many mechanical components. As a result, the vibration signal of a gearbox in the system is strongly coupled with the vibration signatures of other components including a diesel engine and main shaft. It is therefore imperative to assess the coupling effect on diagnostic reliability in the process of gear fault diagnosis. For this reason, a fault detection and diagnosis method based on bispectrum analysis and artificial neural networks (ANNs) was proposed for the gearbox with consideration given to the impact of the other components in marine propulsion systems. To monitor the gear conditions, the bispectrum analysis was first employed to detect gear faults. The amplitude-frequency plots containing gear characteristic sign...

2011-01-01

58

Crawling beneath the free surface: Water snail locomotion  

CERN Document Server

Land snails move via adhesive locomotion. Through muscular contraction and expansion of their foot, they transmit waves of shear stress through a thin layer of mucus onto a solid substrate. Since a free surface cannot support shear stress, adhesive locomotion is not a viable propulsion mechanism for water snails that travel inverted beneath the free surface. Nevertheless, the motion of the freshwater snail, Sorbeoconcha physidae, is reminiscent of that of its terrestrial counterparts, being generated by the undulation of the snail foot that is separated from the free surface by a thin layer of mucus. Here, a lubrication model is used to describe the mucus flow in the limit of small amplitude interfacial deformations. By assuming the shape of the snail foot to be a traveling sine wave and the mucus to be Newtonian, an evolution equation for the interface shape is obtained and the resulting propulsive force on the snail is calculated. This ...

2008-01-01

59

Publications related to the WIND ... - Glenn Research Center - NASA  

Science.gov (United States)

Dippold, V., S. Mohler , Validation of the Wind-US Unstructured Flow Solver .... Hamed, A. and A. Mohamed, Assessment of Shock Induced Flow Separation and ...... Nozzles for Hypersonic Propulsion, NASA CR 185197, AGARD Symposium ...

60

Power electronics in electrical propulsion  

Energy Technology Data Exchange (ETDEWEB)

Various energy sources and motors of divers types can be used in electric cars with operating modes subjected to a number of particular constraints. As a result, the possible structures of the converters, that are analysed in detail, are about a dozen in number. Also considered is the use of solid-state components - thyristors, power transistors and new components.

1982-12-01

61

Outboard Waterjet Propulsion Development.  

Science.gov (United States)

The project is currently on schedule. The design review meeting was held on 08/26/97 at the Coastal Systems Station in Panama City, Florida. The mechanical arrangement, performance analysis and design features were presented at the review meeting. A numbe...

1997-01-01

62

N A S A T'ECHNICAL, - NASA Technical Reports Server  

Science.gov (United States)

Four temperature sensors were provided instead of the previous two sensors. 4. ... Incoming signals from either one or two ground stations at a frequency of .... The propulsion subsystem consists of a single solid-propellant rocket motor. ...

63

Modulation of leg muscle function in response to altered demand for body support and forward propulsion during walking  

UK PubMed Central (United Kingdom)

A number of studies have examined the functional roles of individual muscles during normal walking, but few studies have examined which are the primary muscles that respond to changes in external...Full Text Available

2009-05-11

64

High Speed Cylindrical Roller Bearing Development.  

Science.gov (United States)

High speed experimental tests provided data on six parametric cylindrical roller bearings. Four bearing variables were evaluated and the results were correlated with the analytical model developed under Naval Air Propulsion Center Contract N00140-76-C-038...

1980-01-01

65

FS-1037C Appendix A  

Science.gov (United States)

Telecommunication Union IVDT integrated voice data terminal IXC interexchange carrier JANAP Joint Army-Navy-Air Force Publication(s) JCS Joint Chiefs of Staff JPL Jet Propulsion...

2007-05-31

66

Can treadmill walking be used to assess propulsion generation?  

UK PubMed Central (United Kingdom)

Instrumented treadmills offer significant advantages for analysis of human locomotion, including recording consecutive steady-state gait cycles, precisely controlling walking speed, and avoiding...Full Text Available

2008-01-01

67

Is spent nuclear fuel at the Kola coast a real danger?  

Energy Technology Data Exchange (ETDEWEB)

Norwegian authorities regard with some disquiet the possibility of a criticality accident in a ship propulsion reactor core at the Kola coast. Along this coast, in land storages, floating storages and in submarines taken out of service, the total number of spent fuel reactor cores amount to two hundred. The total Cs-137 radioactivity in spent ship propulsion reactor fuel at the Kola peninsula can be assessed to 600,000 TBq. A worst case release may amount to more than 5,000 TBq Cs-137, a quantity which under unfavourable conditions might cause serious contamination locally and even across the border to Norway.

1995-12-31

68

Germinating a New SEAD: The Implications of Executing the ...  

Science.gov (United States)

... Possessing the unique perspective of space, space-based weapons can immediately ... A weapon system with enough space-based platforms at ...

2001-06-01

70

Remarks of Obama on space exploration in 21st century  

Science.gov (United States)

Apr 22, 2010 ... I believe that space exploration is not a ... plan for space exploration, especially in .... space exploration beyond low Earth orbit. ...

72

BUBL LINK: Space observation  

Wastenet

...Observatory Edinburgh SkyView Virtual Observatory Solar System Simulator Space Telescope Science Institute Space Weather : A Research Perspective Subaru Telescope Project Two Micron All ...Universities for Research in Astronomy Subjects: space observation DeweyClass: 522 Resource type: index Space Weather : A Research Perspective Documents discussing space weather , the ...elements of near-Earth space, Earth-space meteorology and practical consequences of space weather . Glossary included. Author: National Academy of ...

73

Sociology and Space Development  

Science.gov (United States)

As the presence of humans in space expands in scope and duration, the quality of life in space as well as on Earth becomes pertinent. .... Military uses of space, such as the introduction of space-based laser or particle beam weapons, may have a major impact on the way people think and relate to .... AIAA Student Journal. ...

74

This certifies that the face of Flat Granny ... - Face in Space - NASA  

Science.gov (United States)

This certifies that the face of Flat Granny has flown in space aboard the Space Shuttle Discovery on mission STS-. 133 from February 24 - March 9, 2011. ...

75

Marshall Space Flight Center News Release 97-096 (6-9-97)  

Science.gov (United States)

The Bantam System Technology Project is one element of the Advanced Space Transportation Program -- a NASA initiative to reduce the cost of space launch and ...

76

Enhanced Reliability MEMS Deformable Mirrors for Space Imaging ...  

Science.gov (United States)

Sep 3, 2010 ... These higher-quality deformable mirrors will enable diffraction-limited performance for many space-based optical systems such as space-based ...

77

Bounding ingestion stream-tube determination via a CO tracer  

Energy Technology Data Exchange (ETDEWEB)

A gas tracer technique based on carbon monoxide and a commercial automotive exhaust gas analyser has been applied to wind tunnel models of waterjet propulsion systems intakes. The post-processing and interpretation of the carbon monoxide concentration signals has yielded high resolution measurements of the bounding ingestion stream-tubes. (orig.) With 3 figs., 1 tab., 8 refs.

1998-05-01

78

Assessment of the Compositional Variability of RP-1 and RP-2 with the Advanced Distillation Curve Approach.  

Science.gov (United States)

RP-1 is a long-established hydrocarbon fuel that continues to be widely used as the kerosene component in rocket propulsion systems. The desire in recent years to use rocket motors many times, rather than a single time, has led to reformulations of RP-1. ...

2010-01-01

80

Space Task Group Report, 1969 - NASA Headquarters  

Science.gov (United States)

The Space Task Group in its study of future directions in space, with ..... almost $6 billion and a peak civil service and contractor work force of 420000 people. ..... space organizations permitting assumptions of primary or joint responsibility for ...

82

IECEC '87; Proceedings of the Twenty-second Intersociety Energy Conversion Engineering Conference, Philadelphia, PA, Aug. 10-14, 1987. Volumes 1, 2, 3, and 4  

International Nuclear Information System (INIS)

Papers are presented on space power requirements and issues, space photovoltaic systems, space solar dynamic systems, space thermal systems, manned and unmanned space power systems, thermionics, and thermoelectrics. Also considered are high power devices for space power systems, high power conversion for space power systems, 1-10 kWe nuclear space power sources, 100-kW class nuclear power concepts, space reactor safety, and multimegawatt space nuclear power systems. Other topics include space power systems automation, space kilovolt technology, space power electronics, space lithium and nickel-cadmium batteries, lithium sodium storage, and space fuel cells. Papers are also ...

1987-08-10

85

SOVIET SPACE EXPLORATION AS VIEWED BY EAST ...  

Science.gov (United States)

... Accession Number : AD0624575. Title : SOVIET SPACE EXPLORATION AS VIEWED BY EAST GERMAN SPECIALISTS,. ...

1965-11-15

86

Release 01-93 - NASA Human Space Flight  

Science.gov (United States)

These cutting-edge developments will be used for future government and commercial launch systems and space transportation operations. ...

87

NASA/BAE SYSTEMS SpaceWire Effort  

Science.gov (United States)

This paper discusses the state of the NASA and BAE SYSTEMS developments of SpaceWire. NASA has

2003-01-01

88

Losing limits in space exploration  

Science.gov (United States)

JPL's Robert Ferraro explains how the Remote Exploration and Experimentation ( REE) project is addressing ongoing space-exploration needs. ...

89

25th Space Simulation Conference. Environmental Testing: The Earth-Space Connection  

Science.gov (United States)

Topics covered include: Methods of Helium Injection and Removal for Heat Transfer Augmentation; The

2008-01-01

90

Ultra-thin {sup 242m}Am fuel elements in nuclear reactors  

Energy Technology Data Exchange (ETDEWEB)

There is a growing interest in using {sup 242m}Am as a nuclear fuel. The advantages of {sup 242m}Am as a nuclear fuel derive from the fact that {sup 242m}Am has the highest thermal fission cross section. The thermal capture cross section is relatively low and the number of neutrons per thermal fission is high. These nuclear properties make it possible to obtain nuclear criticality with ultra-thin fuel elements. The possibility of having ultra-thin fuel elements enables the use of these fission products directly, without the necessity of converting their energy to heat, as is done in conventional reactors. There are three options of using such highly energetic and highly ionized fission products. - Using the fission products themselves for ionic propulsion. - Using the fission products in an MHD generator, in order to obtain electricity directly. - Using the fission products to heat a gas up to a high temperature for propulsion purposes. In this ...

2000-12-01

91

The ANL electric vehicle battery R&D program for DOE-EHP. Quarterly progress report, October--December 1990  

Energy Technology Data Exchange (ETDEWEB)

The Electrochemical Technology Program at Argonne National Laboratory (ANL) provides technical and programmatic support to DOE`s Electric and Hybrid Propulsion Division (DOE-EBP). The goal of DOE-EHP is to advance promising EV propulsion technologies to levels where industry will continue their commercial development and thereby significantly reduce petroleum consumption in the transportation sector of the US economy. In support of this goal, ANL provides research, development, testing/evaluation, post-test analysis, modeling, database management, and technical management of industrial R&D contracts on advanced battery and fuel cell technologies for DOE-EBP. This report summarizes the objectives, background, technical progress, and status of ANL electric vehicle battery R&D tasks for DOE-EHP during the period of October 1, 1990 through December 31, 1990. The work is organized into the following six task areas: 1.0 Project Management; ...

1990-12-31

92

The ANL electric vehicle battery R&D program for DOE-EHP. Progress report, October 1991--March 1992  

Energy Technology Data Exchange (ETDEWEB)

The Electrochemical Program at Argonne National Laboratory (ANL) provides technical and programmatic support to DOE`s Electric and Hybrid Propulsion Division (DOE-EHP). The goal of DOE-EHP is to advance promising electric-vehicle (EV) propulsion technologies to levels where industry will continue their commercial development and thereby. significantly reduce petroleum consumption in the transportation sector of the economy. In support of this goal, ANL provides research, development, testing/evaluation, post-test analysis, modeling, database management, and technical management of industrial R&D contracts on advanced battery and fuel cell technologies for DOE-EHP. This report summarizes the battery-related activities undertaken during the period of October 1, 1991 through March 31, 1992. In this report, the objective, background, technical progress, and status are described for each task. These tasks are structured into the following task ...

1992-12-31

93

The ANL electric vehicle battery R D program for DOE-EHP  

Energy Technology Data Exchange (ETDEWEB)

The Electrochemical Technology Program at Argonne National Laboratory (ANL) provides technical and programmatic support to DOE's Electric and Hybrid Propulsion Division (DOE-EBP). The goal of DOE-EHP is to advance promising EV propulsion technologies to levels where industry will continue their commercial development and thereby significantly reduce petroleum consumption in the transportation sector of the US economy. In support of this goal, ANL provides research, development, testing/evaluation, post-test analysis, modeling, database management, and technical management of industrial R D contracts on advanced battery and fuel cell technologies for DOE-EBP. This report summarizes the objectives, background, technical progress, and status of ANL electric vehicle battery R D tasks for DOE-EHP during the period of October 1, 1990 through December 31, 1990. The work is organized into the following six task areas: 1.0 Project Management; ...

1990-01-01

94

The ANL electric vehicle battery R D program for DOE-EHP  

Energy Technology Data Exchange (ETDEWEB)

The Electrochemical Program at Argonne National Laboratory (ANL) provides technical and programmatic support to DOE's Electric and Hybrid Propulsion Division (DOE-EHP). The goal of DOE-EHP is to advance promising electric-vehicle (EV) propulsion technologies to levels where industry will continue their commercial development and thereby. significantly reduce petroleum consumption in the transportation sector of the economy. In support of this goal, ANL provides research, development, testing/evaluation, post-test analysis, modeling, database management, and technical management of industrial R D contracts on advanced battery and fuel cell technologies for DOE-EHP. This report summarizes the battery-related activities undertaken during the period of October 1, 1991 through March 31, 1992. In this report, the objective, background, technical progress, and status are described for each task. These tasks are structured into the following ...

1992-01-01

95

The ANL Electrichemical Program for DOE on electric vehicle R&D. Progress report, July--September 1992  

Energy Technology Data Exchange (ETDEWEB)

The Electrochemical Technology Program at Argonne National Laboratory (ANL) provides technical and programmatic support to DOE`s Electric and Hybrid Propulsion Division (DOE-EHP). The goal of DOE-EHP is to advance promising electric-vehicle (EV) propulsion technologies to levels where industry will continue their commercial development and thereby significantly reduce petroleum consumption in the transportation sector of the economy. In support of this goal, ANL provides research, development, testing/evaluation, post-test analysis, modeling, database management, and technical management of industrial R&D contracts on advanced battery technologies for DOE-EHP. This report summarizes the battery-related activities undertaken during the period of July 1, 1992 through September 30, 1992. In this report, the objective, background, technical progress, and status are described for each task. The work is organized into the following task areas: ...

1992-12-31

96

The ANL Electrichemical Program for DOE on electric vehicle R D  

Energy Technology Data Exchange (ETDEWEB)

The Electrochemical Technology Program at Argonne National Laboratory (ANL) provides technical and programmatic support to DOE's Electric and Hybrid Propulsion Division (DOE-EHP). The goal of DOE-EHP is to advance promising electric-vehicle (EV) propulsion technologies to levels where industry will continue their commercial development and thereby significantly reduce petroleum consumption in the transportation sector of the economy. In support of this goal, ANL provides research, development, testing/evaluation, post-test analysis, modeling, database management, and technical management of industrial R D contracts on advanced battery technologies for DOE-EHP. This report summarizes the battery-related activities undertaken during the period of July 1, 1992 through September 30, 1992. In this report, the objective, background, technical progress, and status are described for each task. The work is organized into the following task ...

1992-01-01

97

Diesel fueled ship propulsion fuel cell demonstration project  

Energy Technology Data Exchange (ETDEWEB)

The paper describes the work underway to adapt a former US Navy diesel electric drive ship as a 2.4 Megawatt fuel cell powered, US Coast Guard operated, demonstrator. The Project will design the new configuration, and then remove the four 600 kW diesel electric generators and auxiliaries. It will design, build and install fourteen or more nominal 180 kW diesel fueled molten carbonate internal reforming direct fuel cells (DFCs). The USCG cutter VINDICATOR has been chosen. The adaptation will be carried out at the USCG shipyard at Curtis Bay, MD. A multi-agency (state and federal) cooperative project is now underway. The USCG prime contractor, AEL, is performing the work under a Phase III Small Business Innovation Research (SBIR) award. This follows their successful completion of Phases I and II under contract to the US Naval Sea Systems (NAVSEA) from 1989 through 1993 which successfully demonstrated the feasibility of diesel fueled DFCs. The demonstrated marine ...

1996-12-31

98

Air liquefaction and enrichment system propulsion in reusable launch vehicles  

Energy Technology Data Exchange (ETDEWEB)

A concept is shown for a fully reusable, Earth-to-orbit launch vehicle with horizontal takeoff and landing, employing an air-turborocket for low speed and a rocket for high-speed acceleration, both using liquid hydrogen for fuel. The turborocket employs a modified liquid air cycle to supply the oxidizer. The rocket uses 90% pure liquid oxygen as its oxidizer that is collected from the atmosphere, separated, and stored during operation of the turborocket from about Mach 2 to 5 or 6. The takeoff weight and the thrust required at takeoff are markedly reduced by collecting the rocket oxidizer in-flight. This article shows an approach and the corresponding technology needs for using air liquefaction and enrichment system propulsion in a single-stage-to-orbit (SSTO) vehicle. Reducing the trajectory altitude at the end of collection reduces the wing area and increases payload. The use of state-of-the-art materials, such as graphite polyimide, in a direct substitution for ...

1994-07-01

99

Status Report of Simulated Space Radiation Environment Facility  

Energy Technology Data Exchange (ETDEWEB)

The technology for performance testing and improvement of materials which are durable at space environment is a military related technology and veiled and securely regulated in advanced countries such as US and Russia. This core technology cannot be easily transferred to other country too. Therefore, this technology is the most fundamental and necessary research area for the successful establishment of space environment system. Since the task for evaluating the effects of space materials and components by space radiation plays important role in satellite lifetime extension and running failure percentage decrease, it is necessary to establish simulated space radiation facility and systematic testing procedure. This report has dealt with the status of the technology to enable the simulation of space environment effects, including the effect of ...

2007-11-15

100

Viewpoint: Space System Negation in the Context of Space Policy and Law  

British Library Electronic Table of Contents (United Kingdom)

For 21st century warfare, space is the unquestioned new high ground for military operations. The United States (U.S.) has relied on satellites for significant support to military operations and activities since Desert Storm in 1991. Indeed, the U.S. enjoys an asymmetric advantage in modern warfare utilizing our space capabilities. States with interests hostile to the U.S. believe that the significant dependence on space assets by the U.S. military could become its "Achilles heel" in future combat operations. What are the legal and policy bases for the U.S. to respond to threats to space systems that provide support to our military forces? Should the U.S. rely on space arms control initiatives to ensure security in space? This Viewpoint analyzes the international space law regime and U.S. N...

2007-01-01

101

Study of Japanese electrodynamic-suspension maglev systems  

Energy Technology Data Exchange (ETDEWEB)

This report presents the results of a study of the Japanese MLU magnetic-levitation (maglev) system. The development of the MLU system is reviewed, and the dynamic circuit model then is introduced and applied to the figure-eight-shaped null-flux coil suspension system. Three different types of figure-eight-shaped null-flux suspension systems are discussed in detail: (1) the figure-eight-shaped null-flux coil suspension system without cross-connection; (2) the combined suspension and guidance system; and (3) the combined propulsion, levitation, and guidance system. The electrodynamic-suspension maglev systems developed in Japan seem to be very promising and could result in a commercial application in the near future.

1994-04-01

102

Performance testing of the Ford/GE Second Generation Single-Shaft Electric Propulsion (ETX-II) System  

Energy Technology Data Exchange (ETDEWEB)

System-level-operational testing of the ETX-II test-bed electric vehicle is described and the results discussed. Because the traction battery is a major factor in the performance of an electric vehicle, previously reported work on the sodium-sulfur battery designed for use with the ETX-II is reviewed in detail. Chassis dynamometer performance of the test-bed vehicle met or exceeded design goals and compared reasonably well with SIMPLEV computer modeling results. Areas are identified wherein further work is needed to establish a firmer basis for comparison of the simulation and the observed results.

1993-06-01

103

One-dimensional free boundary problem for actin-based propulsion of Listeria  

Science.gov (United States)

Some bacteria move inside cells by recruiting the actin filaments of the host cells. The filaments are polymerized at the back surface of the bacteria, and they move away, forming a "comet" tail behind the bacterium, which consists of gel network. We develop a one-dimensional mathematical model of the gel based on partial differential equations which involve the number of filaments, the density and velocity of the gel, and the pressure. The two end-points of the gel form two free boundaries. The resulting free boundary problem is rather non-standard. We prove local existence and uniqueness.

2007-04-01

104

Electric and Hybrid Vehicles Program. Sixteenth annual report to Congress for fiscal year 1992  

Energy Technology Data Exchange (ETDEWEB)

This report describes the progress achieved in developing electric and hybrid vehicle technologies, beginning with highlights of recent accomplishments in FY 1992. Detailed descriptions are provided of program activities during FY 1992 in the areas of battery, fuel cell, and propulsion system development, and testing and evaluation of new technology in fleet site operations and in laboratories. This Annual Report also contains a status report on incentives and use of foreign components, as well as a list of publications resulting from the DOE program.

1993-08-01

105

A comprehensive, numerical model of electro-thermal propulsion  

Science.gov (United States)

A computer model of an electrothermal accelerator has been developed which applies to the plasma generator as well as the gun barrel, and it for the first time allows study of the interdependent physical processes in both components simultaneously. The code comprises a 2D transient description of the plasma arc, a 2D, two-phase interior ballistics module, and a preprocessor delivering the required plasma physical data. Some results on the flow field, pressure and temperature in a typical accelerator are presented, and probable limitations on the performance of such a system are discussed. The code is to be applied to different concepts of electrothermal chemical guns.

1993-01-01

106

Fault detection and diagnosis of a gearbox in marine propulsion systems using bispectrum analysis and artificial neural networks  

Science.gov (United States)

A marine propulsion system is a very complicated system composed of many mechanical components. As a result, the vibration signal of a gearbox in the system is strongly coupled with the vibration signatures of other components including a diesel engine and main shaft. It is therefore imperative to assess the coupling effect on diagnostic reliability in the process of gear fault diagnosis. For this reason, a fault detection and diagnosis method based on bispectrum analysis and artificial neural networks (ANNs) was proposed for the gearbox with consideration given to the impact of the other components in marine propulsion systems. To monitor the gear conditions, the bispectrum analysis was first employed to detect gear faults. The amplitude-frequency plots containing gear characteristic signals were then attained based on the bispectrum technique, which could be regarded as an index actualizing forepart gear faults diagnosis. Both the back ...

2011-03-01

107

Design of a propulsion system with double-layer power capacitors and soft-switched converters for a hybrid automobile  

Energy Technology Data Exchange (ETDEWEB)

This thesis examines the design of a propulsion system for a series hybrid vehicle and includes the study of an energy storage unit using double-layer capacitors and a lightweight soft-switched converter system, and two new components in series hybrid vehicles. The development of environmentally sustainable vehicles is more urgent now given the fact that pollution levels are ever increasing. No electric vehicle has yet been developed that can compete with a normal vehicle based only on internal combustion engines. The dilemma lies in the difficulty of storing the amount of energy needed and supply it a high power levels. An attractive and viable option to reducing pollution and maintaining good performance may lie in hybrid electric-powered vehicles. The double-layer power capacitors are an interesting option because of their high power density and long lifetime. The devices are new and assembling large energy storage units must be thoroughly examined before using ...

2001-07-01

108

The phase space of tachyons  

International Nuclear Information System (INIS)

The phase space of quantized systems that contain tachyons has been investigated. Interpretation difficulties and unexpected divergences are found when it is considered the volume of Lorentz-invariant phase space. These problems can be overcome, however, at the expense of Lorentz invariance.

109

Phase space of tachyons  

Energy Technology Data Exchange (ETDEWEB)

The phase space of quantized systems that contain tachyons has been investigated. Interpretation difficulties and unexpected divergences are found when we consider the volume of Lorentz-invariant phase space. These problems can be overcome, however, at the expense of Lorentz invariance.

1983-12-21

110

On removing one point from a compact space  

CERN Document Server

If B is a compact space and B\\{pt} is Lindelof then B^k\\{pt} is star-Linedlof for every cardinality k. If B\\{pt} is compact then B^k\\{pt} is discretely star-Lindelof. In particular, this gives new examples of Tychonoff discretely star-Lindelof spaces with unlimited extent.

2004-01-01

111

In Their Own Words: Charlie Bolden  

National Aeronautics and Space Administration (NASA)

NASA Administrator Charles Bolden, who flew four space shuttle missions, talks about how space travel changed his life and how he applies his astronaut training to his work as the head of the space agency.

2011-10-19

112

GSFC Information Systems Technology Developments Supporting the Vision for Space Exploration.  

Science.gov (United States)

The Vision for Space Exploration will guide NASA's future human and robotic space activities. The broad range of human and robotic missions now being planned will require the development of new system-level capabilities enabled by emerging new technologie...

2005-01-01

113

Decompositions involving Anick's spaces  

CERN Document Server

Recently Stephen Theriault and I found an elementary construction of Anick's spaces and proved their main properties(arXiv:0710.1024).In this work the fundamental fibration is decomposed. This is useful in studying maps out of Anick's spaces and will be needed in order to determine it's universal properties.

2008-01-01

114

Space activities in the Bolivarian Republic of Venezuela  

British Library Electronic Table of Contents (United Kingdom)

This paper summarizes the establishment and current development of space activities in the Bolivarian Republic of Venezuela. Space activities in Venezuela are focused on the areas of telecommunications, Earth observation and research on the physical properties of the Earth, and have as a primary goal the satisfaction of social needs. Current development of space activities started in 1999 when the new National Constitution recognized the value of outer space as the common heritage of mankind, and the key role of science and technology in promoting human welfare. The Bolivarian Agency for Space Activities (ABAE) was created in 2007. Its legal framework recognizes three key elements that drive its policy: the participation of society, capacity building and human training, and international c...

2011-01-01

115

central sports - NASA  

Science.gov (United States)

11 matches ... 04.17.2002. International Space Station Sports a New Truss + More Details. 04.17 .2002. International Space Station Sports a New Truss ...

116

X-15 Research Results: Chapter 9  

Science.gov (United States)

... hypersonic aerodynamic force, or the space-equivalent region. Some of these experiments change the X-15 from a research airplane to a kind of space probe, ...

117

The NASA Ames Small Satellite Program - Goddard Engineering ...  

Science.gov (United States)

He commanded the 50th Space Wing, which is responsible for 60 satellites. ... to produce space systems and launchers capable of tailored military effects on ...

118

Technology for Large Space Systems - NASA Technical Reports Server  

Science.gov (United States)

(AIM PAPER 81-1628). Three different examples will be given to illustrate how a ...... Power System (PS), and a Science Applications and Space Platform ...

119

Space Shuttle Annotated Bibliography, CH14 - NASA's History Office  

Science.gov (United States)

"Report of the Ad Hoc Subpanel on Reusable Launch Vehicle Technology. ... The author comments that the United State's space transportation system is ...

120

Space Food and Nutrition pdf - Space Shuttle Experience - NASA  

Science.gov (United States)

Yellow cake with chocolate frosting. Dairy: Ice cream, chocolate. Ice cream, strawberry. Ice cream, vanilla. Yogurt, frozen ...

121

Phase of space of tachyons  

Energy Technology Data Exchange (ETDEWEB)

The aim of this paper is to present the phase-space properties of the systems that contain bradyons, luxons and tachyons. It is shown that particularly at low energy, these properties are quite different from the well-known properties of bradyons.

1983-03-12

122

On the connectedness of moduli spaces of Calabi-Yau manifolds  

CERN Document Server

We show that the moduli space of all Calabi-Yau manifolds that can be realized as hypersurfaces described by a transverse polynomial in a four dimensional weighted projective space, is connected. This is achieved by exploiting techniques of toric geometry and the construction of Batyrev that relate Calabi-Yau manifolds to reflexive polyhedra. Taken together with the previously known fact that the moduli space of all CICY's is connected, and is moreover connected to the moduli space of the present class of Calabi-Yau manifolds (since the quintic threefold P_4[5] is both CICY and a hypersurface in a weighted P_4), this strongly suggests that the moduli space of all simply connected Calabi-yau manifolds is connected. It is of interest that singular Calabi-Yau manifolds corresponding to the points in which the moduli spaces meet are often, for the present class, ...

1995-01-01

123

Observations of a Unique Type of ULF Waves by Low-Latitude Space Technology Five Mission  

Science.gov (United States)

We report a unique type of ULF waves observed by low-altitude Space Technology 5 (ST-5)

2011-01-01

124

NASA - NASA, National Academies Team On Space Exploration Vision  

Science.gov (United States)

Jul 15, 2004 ... Responding to the recommendations of the President's Commission on Implementation of United States Space Exploration Policy, NASA is teaming ...

125

Marshall Space Flight Center News Release 01-180 (05-17-01)  

Science.gov (United States)

These cutting-edge developments will be used for future government and commercial launch systems and space transportation operations. ...

126

Human Interfaces for Robotic Satellite Servicing  

Science.gov (United States)

... of China Lake Naval Weapons Center, California. ... Figure 4: The Space-Based Laser cleaning ... of Aeronautics and Astronautics (AIAA) Space 2001 ...

2011-05-13

127

Geo-Political Considerations to China's Rise in Space Power  

Science.gov (United States)

... to de-scope the weapon system. ... AIAA American Institute of Aeronautics and Astronomy ... Nations BASIC Broad Area Space-Based Imagery Collector ...

2009-04-01

128

Executive Summary-Department of Defense - NASA History Office  

Science.gov (United States)

Sep 5, 1996 ... In Haiti, the military deployed a space support team to advise the task force commander on the effective use of space assets, such as the Milstar ...

129

Diffusion in Brain Extracellular Space  

UK PubMed Central (United Kingdom)

Diffusion in the extracellular space (ECS) of the brain is constrained by the volume fraction and the tortuosity and a modified diffusion equation represents the transport behavior of many molecules...Full Text Available

2008-10-01

130

Chapter 9 - Columbia Accident Investigation Board - NASA  

Science.gov (United States)

our exploration of space, in a manner with improved safety. ... a new Space Transportation System. ... Columbia launches as STS-107 on January 16, 2003. ...

131

Automated Eddy Current Inspection of Space Shuttle APV ...  

Science.gov (United States)

... perform the inspection in the extremely limited space between adjacent blades and at the blade root, miniature eddy current probes were developed ...

132

Aircraft Survivability: Protecting and Integrating Air and Space ...  

Science.gov (United States)

... reliability of fiber optics in preference over space-based systems. ... STC web site at www.aiaa.org/tc ... and improve lethalities of US weapon systems 3 ...

2011-05-15

133

nasa_d_FEDMACSOILAIRTEMP.xml  

Science.gov (United States)

S.M. Goltz; NASA Goddard Space Flight Center, Forest Ecosystem Dynamics Project ...

134

The Origin of the Universe and the Arrow of Time  

ScienceCinema

...energy back into space model global warming the ? is the energy that ...

135

Synthetic Biology and Human Health: Potential Applications for Spaceflight  

Science.gov (United States)

Human space travelers experience a unique environment that affects homeostasis and physiologic

2011-01-01

136

Space Radiation Detector with Spherical Geometry  

Science.gov (United States)

A particle detector is provided, the particle detector including a spherical Cherenkov detector, and

2011-01-01

137

Space Biology and Medicine  

Science.gov (United States)

Volume IV is devoted to examining the medical and associated organizational measures used to

2004-01-01

140

Integrability and symmetric spaces  

Energy Technology Data Exchange (ETDEWEB)

It is shown that a sufficient condition for a model describing the motion of a particle on a coset space to possess a Fundamental Poisson bracket Relation, and consequently charges in involution, is that it must be a symmetric space. The conditions, a Hamiltonian, or any functions of the canonical variables, has to satisfy in order to commute with these charges, are studied. It is show that, for the case of the noncompact symmetric spaces, these conditions lead to an algebraic structure which lays an important role in the construction of conserved quantities.

1989-01-01

141

ISS Update - Oct. 19, 2011  

National Aeronautics and Space Administration (NASA)

The International Space Station video update for Oct. 19, 2011.

2011-10-19

142

ISS Update - Oct. 18, 2011  

National Aeronautics and Space Administration (NASA)

The International Space Station video update for Oct. 18, 2011.

2011-10-18

143

ISS Update - Oct. 17, 2011  

National Aeronautics and Space Administration (NASA)

The International Space Station video update for Oct. 17, 2011.

2011-10-17

144

ISS Update - Oct. 14, 2011  

National Aeronautics and Space Administration (NASA)

The International Space Station video update for Oct. 14, 2011.

2011-10-14

145

ISS Update - Oct. 13, 2011  

National Aeronautics and Space Administration (NASA)

The International Space Station video update for Oct. 13, 2011. n

2011-10-13

146

Biophotonics and Bone Biology  

Science.gov (United States)

One of the more-serious side effects of extended space flight is an accelerated bone loss

2004-01-01

147

An octonionic representation of the Poincare group  

International Nuclear Information System (INIS)

... energy levels hilbert space irreducible representations nonunitary

148

A lateral cephalometric study of the size of tongue and intermaxillary space in Korean  

International Nuclear Information System (INIS)

A study was performed to investigate the size of tongue area and intermaxillary space area, and compare the sexual differences between normal Korean children and adults by introducing planimetric and linear analysis of the lateral cephalograms. The cephalograms were composed of 41 child male aged 10.8, 40 child female aged 10.5, 38 adult male aged 21.3 , and 40 adult female aged 20.8 respectively. In order to study and measure the intermaxillary space area, the following were selected, as reference items: occlusal plane, anterior intermaxillary space height, posterior intermaxillary space height, length of intermaxillary space. Among those reference items anterior intermaxillary space height and posterior intermaxillary space height were perpendicular to the maxillary plane. An index, (Anterior intermaxillary space ...

1977-11-01

149

Pilot studies at industrial sources with an electrostatic precipitator having wide plate spacing. Pilotuntersuchungen an industriellen Quellen mit einem elektrischen Abscheider grosser Gassenweite  

Energy Technology Data Exchange (ETDEWEB)

With a pilot electrostatic precipitator having wider plate spacings than usual tests were performed under industrial conditions. In the two-section two-duct pilot precipitator with a precipitation area of 60 m/sup 2/ the plate spacing was increased up to 1,000 mm. As gas velocities values between 0.5 and 2.0 m/s were selected. The precipitator was tested with the flue gases of a coal-fired power station and in the room dedustion of an iron ore sintering plant. Starting with a plate spacing of 250 mm increasing the spacing results initially in a small increase of the precipitation rate. After reaching a maximum the rate decreases and finally with passing a critical spacing it goes below the initial value. Dedusting flue gases the spacing with the maximum and the critical spacing depend on the gas velocity. Cost analyses demonstrate that ...

1983-01-01

150

IECEC '91; Proceedings of the 26th Intersociety Energy Conversion Engineering Conference, Boston, MA, Aug. 4-9, 1991. Vol. 2 - Aerospace power systems, conversion technologies  

International Nuclear Information System (INIS)

The present volume on energy and the environment discusses space power requirements, space power systems, space power systems hardware, space radioisotope systems, space solar arrays, space solar cells, space station power, and terrestrial applications of aerospace technology. Attention is given to NASA future space power requirements and issues, the design of a battery charger for the NASA EOS Space Platform, in situ carbon dioxide fixation on Mars, and a preliminary design update of the CRAF/Cassini Power Subsystem. Topics addressed include concentrator testing using projected images, solar power satellites and demonstraton platforms from nonterrestrial materials, a mass sensitivity analysis of lunar orbiting beam power systems, and a power-beaming-based infrastructure for ...

1991-08-03

151

Multi-megawatt space power reactors  

Energy Technology Data Exchange (ETDEWEB)

In response to the need of the Strategic Defence Initiative (SDI) and long range space exploration and extra-terrestrial basing by the National Air and Space Administration (NASA), concepts for nuclear power systems in the multi-megawatt levels are being evaluated. The requirements for these power systems are being driven primarily by the need to minimize weight and maximize safety and reliability. This paper discusses the present requirements for space based advanced power systems, technological issues associated with the development of these advanced nuclear power systems, and some of the concepts proposed for generating large amounts of power in space. (author).

1990-01-01

152

Extended covariance under nonlinear canonical transformation in Weyl quantization  

CERN Document Server

A theory of nonunitary-invertible as well as unitary canonical transformations is formulated in the context of Weyl's phase space representations. Exact solutions of the transformation kernels and the phase space propagators are given for the three fundamental canonical maps as fractional-linear, gauge and contact (point) transformations. Under the nonlinear maps a phase space representation is mapped to another phase space representation thereby extending the standard concept of covariance. This extended covariance allows Dirac-Jordan transformation theory to naturally emerge from the Hilbert space representations in the Weyl quantization.

2000-01-01

153

Zinc/air battery R and D zinc/air engineering analysis for electrical vehicles: Tasks III, Final report  

Energy Technology Data Exchange (ETDEWEB)

This report is an examination and analysis of the zinc-air system as the motive power source for electric vehicle propulsion. Various versions of the zinc-air system and operating schemes along with their advantages and disadvantages are discussed. Baseline cost calculations are also presented in order to compare the cost effectiveness of each of the systems. The treatise is conceptual in nature and is not based on new experimental work. The information is based on published literature and investigations carried out at ERC in the past. The study also includes recommendations and suggestions in areas that require further research and development work to achieve a smooth transition from the conceptual stage to a practical, viable, and cost effective system.

1986-12-01

154

Unitized regenerative fuel cell systems  

Energy Technology Data Exchange (ETDEWEB)

Energy storage systems with extremely high specific energy (>400 Wh/kg) have been designed that use lightweight pressure vessels to contain the gases generated by reversible (unitized) regenerative fuel cells (URFCs).[1] URFC systems are being designed and developed for a variety of applications, including high altitude long endurance (HALE) solar rechargeable aircraft (SRA), zero emission vehicles (ZEVs), hybrid energy storage/propulsion systems for spacecraft, energy storage for remote (off-grid) power sources, and peak shaving for on-grid applications.[1-10] Energy storage for HALE SRA was the original application for this set of innovations, and a prototype solar powered aircraft (Pathfinder-Plus) recently set another altitude record for all propeller-driven aircraft on August 6, 1998, when it flew to 80,285 feet (24.47 km).[11

1998-09-10

155

The Xygra gun simulation tool.  

Energy Technology Data Exchange (ETDEWEB)

Inductive electromagnetic launchers, or coilguns, use discrete solenoidal coils to accelerate a coaxial conductive armature. To date, Sandia has been using an internally developed code, SLINGSHOT, as a point-mass lumped circuit element simulation tool for modeling coilgun behavior for design and verification purposes. This code has shortcomings in terms of accurately modeling gun performance under stressful electromagnetic propulsion environments. To correct for these limitations, it was decided to attempt to closely couple two Sandia simulation codes, Xyce and ALEGRA, to develop a more rigorous simulation capability for demanding launch applications. This report summarizes the modifications made to each respective code and the path forward to completing interfacing between them.

2008-12-01

156

Sulzer RTA dual-fuel engine - natural gas instead of diesel oil  

Energy Technology Data Exchange (ETDEWEB)

Testbed trials of the Sulzer RTA84 dual-fuel engine were successfully completed at the IHI Aioi engine works (Japan) in April 1986. This newly-developed engine, output range 15 to 40 MW, can be operated with both diesel or heavy oil and methane gas at comparable thermal efficiency and unchanged output. The RTA dual-fuel engine was developed in close collaboration between Sulzer Brothers Limited, Switzerland and its Japanese licensees Ishikawajima-Harima Heavy Industries Co. Ltd. (IHI), Nippon Kokan KK (NKK) and Sumitomo Heavy Industries Ltd. (SHI). Intended for the propulsion of LNG carriers, where the boil-off gas from the ship's cargo is exploited or for the generation of electricity in stationary plants, the RTA dual-fuel engine is an economic and reliable alternative to the steam or gas turbines.

1987-06-01

157

Some preliminary views of plasma interaction: electromagnetic-launch systems  

Energy Technology Data Exchange (ETDEWEB)

This discussion outlines a few areas of fundamental research which appear vital for progress in developing advanced propulsion concepts using dc railgun thrusters. We have placed emphasis on the following: (1) dense plasma and high current density influences on changes in microstructure and properties of conventional rail conductors such as Cu, Al, and W alloys or composites; (2) the influences described in (1) on more advanced high temperature, microstrain resistant, materials such as amorphous tungsten; (3) location, description and temporal evolution of current, magnetic field, and losses during intense plasma-current field interactions with conductors; and (4) composite materials and sequentially sectioned structures for more efficient EM dc launcher configuration.

1982-07-14

158

Solar thermal aircraft  

Energy Technology Data Exchange (ETDEWEB)

A solar thermal powered aircraft powered by heat energy from the sun. A heat engine, such as a Stirling engine, is carried by the aircraft body for producing power for a propulsion mechanism, such as a propeller. The heat engine has a thermal battery in thermal contact with it so that heat is supplied from the thermal battery. A solar concentrator, such as reflective parabolic trough, is movably connected to an optically transparent section of the aircraft body for receiving and concentrating solar energy from within the aircraft. Concentrated solar energy is collected by a heat collection and transport conduit, and heat transported to the thermal battery. A solar tracker includes a heliostat for determining optimal alignment with the sun, and a drive motor actuating the solar concentrator into optimal alignment with the sun based on a determination by the heliostat.

2007-09-18

159

Small propulsion reactor design based on particle bed reactor concept  

Science.gov (United States)

In this paper Particle Bed Reactor (PBR) designs are discussed which use /sup 233/U and /sup 242m/Am as fissile materials. A constant total power of 100MW is assumed for all reactors in this study. Three broad aspects of these reactors is discussed. First, possible reactor designs are developed, second physics calculations are outlined and discussed and third mass estimates of the various candidates reactors are made. It is concluded that reactors with a specific mass of 1 kg/MW can be envisioned of /sup 233/U is used and approximately a quarter of this value can be achieved if /sup 242m/Am is used. If this power level is increased by increasing the power density lower specific mass values are achievable. The limit will be determined by uncertainties in the thermal-hydraulic analysis. 5 refs., 5 figs., 6 tabs.

1989-01-01

160

Rankine-Brayton engine powered solar thermal aircraft  

Energy Technology Data Exchange (ETDEWEB)

A solar thermal powered aircraft powered by heat energy from the sun. A Rankine-Brayton hybrid cycle heat engine is carried by the aircraft body for producing power for a propulsion mechanism, such as a propeller or other mechanism for enabling sustained free flight. The Rankine-Brayton engine has a thermal battery, preferably containing a lithium-hydride and lithium mixture, operably connected to it so that heat is supplied from the thermal battery to a working fluid. A solar concentrator, such as reflective parabolic trough, is movably connected to an optically transparent section of the aircraft body for receiving and concentrating solar energy from within the aircraft. Concentrated solar energy is collected by a heat collection and transport conduit, and heat transported to the thermal battery. A solar tracker includes a heliostat for determining optimal alignment with the sun, and a drive motor actuating the solar concentrator into optimal alignment with the ...

2009-12-29

161

RTA dual-fuel engine - natural gas instead of diesel oil  

Energy Technology Data Exchange (ETDEWEB)

Test bed trials of the Sulzer RTA84 dual-fuel engine were successfully completed at the IHI Aioi engine works (Japan) in April 1986. This newly-developed engine-type, output range 15 to 40 MW, can be operated with both diesel or heavy oil and methane gas at comparable thermal efficiency and unchanged output. The RTA dual-fuel engine was developed in close collaboration between Sulzer Brothers Limited and its Japanese licenses. Intended for the propulsion of LNG carriers, where the boil-off gas from the ship's cargo is exploited for the generation of electricity in stationary plants, the RTA dual-fuel engines is an economic and reliable alternative to the steam or gas turbine. The performance of the engine is discussed.

1987-01-01

162

New developments in the Electric Fuel Ltd. zinc/air system  

Energy Technology Data Exchange (ETDEWEB)

Electric Fuel Ltd. is engaged in the design, development and commercialization of its proprietary zinc/air battery technology for electric vehicles, consumer electronic products and defence applications. To meet the challenging requirements for propelling an all-electric bus, the Vehicle Division sought a unique solution: an all electric battery-battery hybrid propulsion system. The high energy zinc/air battery is coupled with a high-power auxiliary battery. The combined system offers zero emission, high power and long range in an economically viable package. The consumer battery group has developed a high power primary zinc/air cell aimed at cellular phone users, offering extended use, convenience and low cost. (orig.)

1999-07-01

163

Compression molded energy storage flywheels  

Energy Technology Data Exchange (ETDEWEB)

Flywheels containing fiber-reinforced composite materials have attributes suitable for vehicular propulsion, indicating the need for rotor designs which are easily manufactured and low in cost. This development goal was pursued in a cooperative effort between Owens-Corning Fiberglas and Lawrence Livermore Laboratory which investigated flywheels made from compression-molded sheet molding compound (SMC). The design resulted from a Lawrence Livermore analysis, with successful fabrication achieved using a procedure developed by Owens-Corning. Details concerning materials selection, rotor fabrication, and testing are discussed. Owens-Corning subsequently initiated a technical/marketing survey to determine current industrial interests in a low-cost flywheel design; precursory information, pertaining to composite flywheels in particular, is described.

1982-08-01

164

Airbags to Martian Landers: Analyses at Sandia National Laboratories  

Energy Technology Data Exchange (ETDEWEB)

A new direction for the national laboratories is to assist US business with research and development, primarily through cooperative research and development agreements (CRADAs). Technology transfer to the private sector has been very successful as over 200 CRADAs are in place at Sandia. Because of these cooperative efforts, technology has evolved into some new areas not commonly associated with the former mission of the national laboratories. An example of this is the analysis of fabric structures. Explicit analyses and expertise in constructing parachutes led to the development of a next generation automobile airbag; which led to the construction, testing, and analysis of the Jet Propulsion Laboratory Mars Environmental Survey Lander; and finally led to the development of CAD based custom garment designs using 3D scanned images of the human body. The structural analysis of these fabric structures is described as well as a more traditional example Sandia with the ...

1994-03-01

165

Aerodynamic and structural design of a solar-powered micro unmanned air vehicle  

Energy Technology Data Exchange (ETDEWEB)

The field of micro unmanned aerial vehicles ({mu}UAVs) has advanced rapidly in recent years. This paper studies the design and construction of a small solar-powered aircraft near the size range of current {theta}UAVs. A number of aspects of their design were analysed, including structural, aerodynamic and propulsion system considerations. The effect of small-scale, low Reynolds number aerodynamics was investigated, and the performance of a range of candidate aerofoils was compared. The integration of a solar power source into the aircraft system was considered a key design issue. Consequently, a number of aircraft configurations were examined, with the intention of optimising the application of solar power in a miniature aircraft. Investigation of improved system components suggests that a practical solar-powered aircraft in the size range below 500 mm maximum linear dimension should be viable given modest technological improvements. (Author)

2000-04-01

166

A study of solar-powered, high-altitude unmanned aerial vehicles  

British Library Electronic Table of Contents (United Kingdom)

Purpose ? Aims to present a methodology for analysing a solar-electric, high-altitude, long-endurance, unmanned aircraft. Design/methodology/approach ? The study focuses on the aerodynamics, flight performance and power requirements of a heavier-than-air, solar-electric, HALE UAV. The methodology is founded on using an analytical approach to determine the power required to undertake various flight manoeuvres. An analytical approach is also undertaken in determining the intensity of the solar radiation available to the aircraft. Finally to demonstrate the methodology, a HALE concept was generated and evaluated. Findings ? When using estimates of current solar-electric propulsion and energy conversion efficiencies, the HALE concept was only able to sustain year round, level flight up to lati...

2006-01-01

167

A fluid structure coupling of the Ariane-5 nozzle section during start phase by detached eddy simulation  

British Library Electronic Table of Contents (United Kingdom)

Concerning the requirements of future rocket technologies, providing a cost-efficient access to orbit as well as an increase in system reliability, a deeper insight into the unsteady phenomena during ascent of modern launchers is essential. Unsteady interactions and resonances of the turbulent separated launcher wake and the nozzle structure play an important role for the design of future main stage propulsion systems. The so-called buffeting coupling phenomenon is one of the main challenges during ascent. In the present study, a coupled simulation of the afterbody of the Ariane-5 launcher with a realistic structural and aerodynamic representation of different nozzle configurations is carried out. On the computational fluid dynamics side, unsteady detached eddy simulations are coupled with...

2011-01-01

168

The SOS-LUX-TOXICITY-Test on the International Space Station  

British Library Electronic Table of Contents (United Kingdom)

For the safety of astronauts and to ensure the stability and integrity of the genome of microorganisms and plants used in bioregenerative life support systems, it is important to improve our knowledge of the combined action of (space) radiation and microgravity. The SOS-LUX-TOXICITY test, as part of the TRIPLE-LUX project (accepted for flight at Biolab in Columbus on the International Space Station, (ISS)), will provide an estimation of the health risk resulting from exposure of astronauts to the radiation environment of space in microgravity. The project will: (i) increase our knowledge of biological/health threatening action of space radiation and enzymatic DNA repair; (ii) uncover cellular mechanisms of synergistic interaction of microgravity and space radiation; (iii) provide specified...

2006-01-01

169

From quaternions to cosmology: spaces of constant curvature, ca. 1873-1925  

CERN Document Server

After mathematicians and physicists had learned that the structure of physical space was not necessarily Euclidean, it became conceivable that the global topological structure of space was non-trivial. In the context of the late 19th century debates on physical space this speculation gave rise to the problem of classifying spaces of constant curvature from a topological point of view. William Kingdon Clifford, Felix Klein and Wilhelm Killing, the latter of whom devoted a substantial amount of work to the topic in the early 1890s, clearly perceived this problem as relevant for both mathematics and natural philosophy (i.e., physics or cosmology). To some extent, a cosmological interest may even be found among those authors who restated the space form problem in more modern terms in the early 20th century, such as Heinz Hopf.

2003-01-01

170

High power battery test methods for hybrid vehicle applications  

Energy Technology Data Exchange (ETDEWEB)

Commonly used EV battery tests are not very suitable for testing hybrid vehicle batteries, which may be primarily intended to supply vehicle acceleration power. The capacity of hybrid vehicle batteries will be relatively small, they will typically operate over a restricted range of states-of-charge, and they may seldom if ever be fully recharged. Further, hybrid propulsion system designs will commonly impose a higher regeneration content than is typical for electric vehicles. New test methods have been developed for use in characterizing battery performance and life for hybrid vehicle use. The procedures described in this paper were developed from the requirements of the government-industry cooperative Partnership for A New Generation of Vehicles (PNGV) program; however, they are expected to have broad application to the testing of energy storage devices for hybrid vehicles. The most important performance measure for a high power battery is its pulse power ...

1997-11-01

171

i " GeorgeC. Marshall Space Flight Center _i. Marshall SpaceFlight ...  

Science.gov (United States)

learning curve values as observed from data taken to plot a trend .... Log QF = Log F1 + Log F2 + Log F3 + Log F4 ffi 2.98227 . ...

172

Virtual adult ears reveal the roles of acoustical factors and experience in auditory space map development  

UK PubMed Central (United Kingdom)

Auditory neurons in the superior colliculus (SC) respond preferentially to sounds from restricted directions to form a map of auditory space. The development of this representation is shaped...Full Text Available

2008-11-05

173

Unified kinematics of bradyons and tachyons in six-dimensional space-time  

International Nuclear Information System (INIS)

An explicit form of the transformation matrix in sin-dimensional space-time is given both for subluminal and superluminal cases, and it is shown how a single formalism can be used for both bradyons and tachyons. (author).

174

Surgicopathological classification of hepatic space-occupying lesions: A single-center experience with literature review  

UK PubMed Central (United Kingdom)

Accompanying rapid developments in hepatic surgery, the number of surgeries and identifications of histological types of primary hepatic space-occupying lesions (PHSOLs) have increased dramatically....Full Text Available

2011-05-21

175

Successful Launches to Orbit on U.S. Launch Vehicles  

Science.gov (United States)

Milstar 2. (USA 115). 60A. Titan IV. Nov. 12, 1995. Install Docking Module on the Mir space. 396 km. Second of 9 planned flights. Space Shuttle Atlantis ...

176

Robotic Waterjet System.  

Science.gov (United States)

NASA needed a way to safely strip old paint and thermal protection material from reusable components from the Space Shuttle; to meet this requirement, Marshall Space Flight Center teamed with United Technologies' USBI Company and developed a stripping sys...

1996-01-01

177

Quasi-metrics, Similarities and Searches: aspects of geometry of protein datasets  

CERN Document Server

A quasi-metric is a distance function which satisfies the triangle inequality but is not symmetric: it can be thought of as an asymmetric metric. The central result of this thesis, developed in Chapter 3, is that a natural correspondence exists between similarity measures between biological (nucleotide or protein) sequences and quasi-metrics. Chapter 2 presents basic concepts of the theory of quasi-metric spaces and introduces a new examples of them: the universal countable rational quasi-metric space and its bicompletion, the universal bicomplete separable quasi-metric space. Chapter 4 is dedicated to development of a notion of the quasi-metric space with Borel probability measure, or pq-space. The main result of this chapter indicates that `a high dimensional quasi-metric space is close to being a metric space'. Chapter 5 investigates the ...

2008-01-01

178

Onboard Systems Record Unique Videos of Space Missions - NASA  

Science.gov (United States)

May 1, 2011 ... Onboard Systems Record Unique Videos of Space Missions ... Corporation, An artist's rendering of LCROSS launching toward the Moon .... Station (ISS) as part of the Commercial Orbital Transportation Services program. ...

179

Numerical optimization of spherical variable-line-spacing grating X-ray spectrometers  

UK PubMed Central (United Kingdom)

Operation of an X-ray spectrometer based on a spherical variable-line-spacing (VLS) grating is analyzed using dedicated ray-tracing software allowing fast optimization of the grating parameters and...Full Text Available

2011-03-01

180

NASA reopens space station job notices - Johnson Space Center  

Science.gov (United States)

Oct 11, 1993 ... Lease: Meadowgreen,3-2.5-2, 2 storyon cuI- ..... also will have the Lunar Landing Training Vehicle elevated over the center of the ...

181

LUNAR RESOURCES. J. Edmunson, BAE Systems/NASA Marshall Space ...  

Science.gov (United States)

J. Edmunson, BAE Systems/NASA Marshall Space Flight Center (320 Sparkman Drive. VP61, Huntsville AL 35805, Jennifer.E.Edmunson@nasa.gov). ...

182

Expedition crew rotation highlights upcoming shuttle mission  

Science.gov (United States)

Feb 23, 2001 ... Florida, as an F-16 weapons separation engineer with .... new era of space-based research aboard the International Space. Station. ..... the Web at: http://www. aiaa.org/calen- dar/index.hfm?cal=1&cfp=1 ...

183

Enhanced tube inner surface heat transfer device and method  

Science.gov (United States)

An inner surface substrate of metal tubes is provided with a single layer of randomly distributed metal bodies bonded to the substrate, spaced from each other, and substantially surrounded by the substrate to form body void space.

1979-05-15

184

Development of a coal fired pulse combustor for residential space heating. Technical progress report, October--December 1986  

Energy Technology Data Exchange (ETDEWEB)

This progress report presents a detailed description of the background, technology and application, and Statement of Work for the development of a coal-fired pulse combustor for residential space heating.

1986-12-31

185

Astronaut Jeff Williams Answers Your Questions  

National Aeronautics and Space Administration (NASA)

Expedition 22 Commander Jeff Williams, aboard the International Space Station 220 miles above Earth, responds to questions posted on YouTube concerning the station's orientation, life in space and the recent butterfly experiment.

2010-03-10

186

A relativistic semigroup, the Lorentz group and tachyons  

International Nuclear Information System (INIS)

The construction of the linear isomorphous and relativistic semigroup, of the Lorentz group and of tachyons was done using a dual pair of space-times, where the sought realization of the parametric semigroup is the semigroup of relativist endomorphisms. The obtained relativistic semigroup of dual space-time transformations possesses certain theoretical-probability properties.

187

Weekly ISS Recap - Oct. 10-14, 2011  

National Aeronautics and Space Administration (NASA)

The weekly International Space Station video recap for Oct. 10-14, 2011.

2011-10-14

188

Transformational Satellite (TSAT) Communications Systems. ...  

Science.gov (United States)

... The seven existing space/airborne programs are the Defense Satellite Com- munications System (DSCS), Milstar, communications re- lay ...

2007-07-01

189

Tolerance analysis of a phase space beam analyzer  

Science.gov (United States)

The phase space beam analyzer is a measurement instrument that is applied in laser technology to perform analyses of the spatial and angular distribution of rays. We are interested in this instrument as a means to characterize non-coherent light sources. In this context, a closer look at the tolerances of this optical instrument was considered useful. Having a so-called quadrupole lens as a key element, the phase space beam analyzer is a device that features anamorphic optical properties. To describe these anamorphic properties, recurrence was made to a description by extended ray-transfer matrices. This formalism allows for an analysis of the alignment tolerances of the phase space beam analyzer and facilitates a study of the sensitivities of the instrument. The analysis is complemented using numerical ray tracing.

2007-09-01

190

Station Crew Wishes Buzz Aldrin Luck On 'Dancing'  

National Aeronautics and Space Administration (NASA)

International Space Station astronauts Jeff Williams and T.J. Creamer wish Buzz Aldrin luck on

2010-03-17

191

Simultaneity: A Question of Time, Space, Resources and ...  

Science.gov (United States)

... even divisions. ... hours on 25 October.62 The 82nd Airborne Division and a Marine Amphibious Unit followed the Rangers. ...

2001-05-01

192

SPACE FLIGHT 1999 - NASA  

Science.gov (United States)

Mission losses were incurred by an early warning satellite and a Milstar-2 communications satellite when their launch vehicles malfunctioned, the first, ...

193

Power Beaming, Orbital Debris Removal, and Other Space ...  

Science.gov (United States)

... transition to couple the emitted spontaneous radiation with the ammonia molecules and thus provide more amplification [2]. ...

2010-03-01

194

Photodiode Scintillation Detector for Anti-Coincidence Shielding  

Science.gov (United States)

Photodiode Scintillation Detector for Anticoincidence Shielding An important goal of space research is to understand the physics involved in the activity of ...

195

Operating Manual for Single-Shot Autocorrelator  

Science.gov (United States)

... pulses by a 50/50 beamsplitter and recombined in space and in time inside a wafer of KDP crystal which generates a second harmonic of the ...

1993-01-01

196

Neutrino viscosity in Bianchi type IX universes  

International Nuclear Information System (INIS)

The authors investigate the isotropization of anisotropic closed spaces and the entropy production due to neutrino viscosity. (Auth.).

197

Mike Dickerson - NASA Quest  

Science.gov (United States)

Before working at JPL he was the Chief Engineer for the Milstar Satellite Avionics and several Military space programs. His technical background is in ...

198

Laser-Based Method for Docking an Unmanned Underwater ...  

Science.gov (United States)

... space vehicles, robot and machine guidance systems, and in various types of autonomous UUV docking situations. Page 3. ...

2010-02-08

200

High performance AlGaN/GaN HEMTs with 2.4 #mu#m source-drain spacing  

International Nuclear Information System (INIS)

This paper describes the performance of AlGaN/GaN HEMTs with 2.4 #mu#m source-drain spacing. So far these are the smallest source-drain spacing AlGaN/GaN HEMTs which have been implemented with a domestic wafer and domestic process. This paper also compares their performance with that of 4 #mu#m source-drain spacing devices. The former exhibit higher drain current, higher gain, and higher efficiency. It is especially significant that the maximum frequency of oscillation noticeably increased. (semiconductor integrated circuits)

2010-03-01

201

Generalized Tonnetze  

British Library Electronic Table of Contents (United Kingdom)

We study a generalization of the classical Riemannian Tonnetz to N-tone equally tempered scales (for all N) and arbitrary triads. We classify all the spaces that result. The torus turns out to be the most common possibility, especially as N grows. Other spaces include 2-simplices, tetrahedra boundaries, and the harmonic strip (in both its cylinder and Mobius band variants). The final and most exotic space we find is something we call a 'circle of tetrahedra boundaries'. These are the Tonnetze for spaces of triads which contain a tritone. They are closely related to Peck's Klein bottle Tonnetz.

2011-01-01

202

Forging Space Warriors  

Science.gov (United States)

... These three roles are critical to de- fending the Nation through the control Milstar satellite on Titan IV at Cape Canaveral. ...

2011-05-15

203

Evaluation of the Reformation of Navy Personally Procured ...  

Science.gov (United States)

... POVs) overseas when space was available. ... information management system launched in 2004. ... Personally Procured Transportation (PPT) system ...

2010-12-01

204

ECONOMICS OF RELIABILITY IMPROVEMENT FOR SPACE ...  

Science.gov (United States)

... Pagination or Media Count : 205. Abstract : Present methods for planning reliability improvement of launch vehicles are reviewed. ...

1968-06-01

205

Arms Control and Nonproliferation Activities: A Catalog of ...  

Science.gov (United States)

... testing and deployment of space-based, sea-based ... recognized as nuclear weapon possessors by ... possess significant nuclear weapons capabilities ...

2005-01-07

206

APOD: 2009 May 25 - Hubble Floats Free  

Science.gov (United States)

Space Telescope is currently planned for launch in 2014. Tomorrow's picture: galactic whirlpool ...

2011-10-07

207

3rd GOES Users' Conference  

Science.gov (United States)

with the support and cooperation of the American Meteorological Society, the Marine Technology Society, the National Aeronautics and Space Administration, the National Institute...

2011-10-08

208

27 - NASA  

Science.gov (United States)

02.10.10 - NASA and Texas Instruments are using the theme of human space exploration to develop digital libraries of math and science problems for high ...

209

165.37 22,_  

Science.gov (United States)

Aluminum electrolytic capacitors have a long history of reliable operation in unattended field sites. However, their use in the expected space applications ...

210

Voronoi distance based prospective space-time scans for point data sets: a dengue fever cluster analysis in a southeast Brazilian town  

UK PubMed Central (United Kingdom)

BackgroundThe Prospective Space-Time scan statistic (PST) is widely used for the evaluation of space-time clusters of point event data. Usually a window of cylindrical shape is employed,...Full Text Available

211

Time travel in Goedel's space  

International Nuclear Information System (INIS)

An analysis is presented of the motion of test particles in Goedel's universe. Both geodesical and nongeodesical motions are considered; the accelerations for nongeodesical motions are given. Examples for closed timelike world lines are shown and the dynamical conditions for time travel in Goedel's space-time are discussed. It is shown that these conditions alone do not suffice to exclude time travel in Goedel's space-time. (author).

1981-01-01

212

Third SEI Technical Interchange: Proceedings. [Space Exploration Initiative  

Science.gov (United States)

Given here are the proceedings of the 3rd Space Exploration Initiative (SEI) Technical Interchange. Topics covered include the First Lunar Outpost (FLO), the Lunar Resource Mapper, lunar rovers, lunar habitat concepts, lunar shelter construction analysis, thermoelectric nuclear power systems for SEI, cryogenic storage, a space network for lunar communications, the moon as a solar power satellite, and off-the-shelf avionics for future SEI missions.

1992-01-01

213

Thermal stresses in the space shuttle orbiter: Analysis versus test  

International Nuclear Information System (INIS)

Significant temperature differences occur between the internal structure and the outer skin of the Space Shuttle Orbiter as it returns from space. These temperature differences cause important thermal stresses. A finite element model containing thousands of degrees of freedom is used to predict these stresses. A ground test was performed to verify the prediction method. The analysis and test results compare favorably. (orig.).

214

Target space duality II: applications  

Energy Technology Data Exchange (ETDEWEB)

We apply the framework developed in Target space duality I: general theory. We show that both nonabelian duality and Poisson-Lie duality are examples of the general theory. We propose how the formalism leads to a systematic study of duality by studying few scenarios that lead to open questions in the theory of Lie algebras. We present evidence that there are probably new examples of irreducible target space duality.

2000-09-25

215

Simplified solar fraction estimation for space and water heating at DOD installations. appendix b. space heating nomographs. Final report  

Energy Technology Data Exchange (ETDEWEB)

A set of nomographs is presented which can be used to estimate the average annual solar fraction for solar space and water heating at a large number of DOD facilities. The solar fraction estimated from the nomograph is in close agreement with F-Chart 3.0 and allows for variation of the following parameters: annual load, collector area, collector transmittance-absorptance coefficient, and collector overall loss coefficient.

1982-09-01

216

Scalar fields in the dimensional reduction scheme for symmetric spaces  

Energy Technology Data Exchange (ETDEWEB)

The authors study the general features of the dimensional reduction scheme for multi-dimensional spaces of the type M/sup 4/ x S/R, S/R being a symmetric coset space. The properties of the scalar potentials of the reduced theories are investigated and an effective method of explicit calculation of these potentials is elaborated. They consider also a wide class of embeddings of Lie subalgebras into simple Lie algebras resulting in reduced theories of physical interest.

1989-01-01

217

Representations of the conformal Lie algebra in the space of tensor densities on the sphere  

CERN Document Server

Let ${\\mathcal F}_\\lambda(\\mathbb{S}^n)$ be the space of tensor densities on $\\mathbb{S}^n$ of degree $\\lambda$. We consider this space as an induced module of the nonunitary spherical series of the group $\\mathrm{SO}_0(n+1,1)$ and classify $(\\mathrm{so}(n+1,1),\\mathrm{SO}(n+1))$-sim$unitary submodules of ${\\mathcal F}_\\lambda(\\mathbb{S}^n)$ as a function of $\\lambda$.

2003-01-01

218

Perspectives on energy storage wheels for space station application  

Energy Technology Data Exchange (ETDEWEB)

Several of the issues of the workshop are addressed from the perspective of a potential Space Station developer and energy wheel user. Systems considerations are emphasized rather than component technology. The potential of energy storage wheel (ESW) concept is discussed. The current status of the technology base is described. Justification for advanced technology development is also discussed. The study concludes that energy storage in wheels is an attractive concept for immediate technology development and future Space Station application.

1984-11-01

219

Handling boundary constraints for numerical optimization by particle swarm flying in periodic search space  

CERN Document Server

The periodic mode is analyzed together with two conventional boundary handling modes for particle swarm. By providing an infinite space that comprises periodic copies of original search space, it avoids possible disorganizing of particle swarm that is induced by the undesired mutations at the boundary. The results on benchmark functions show that particle swarm with periodic mode is capable of improving the search performance significantly, by compared with that of conventional modes and other algorithms.

2005-01-01

220

Energy spectra and electromagnetic properties in lithium isotopes  

International Nuclear Information System (INIS)

Li shell-model calculation has been made in the isospin formalism in the complete (0 + n)#Planck constant##omega# model space with the assumption of a closed core "4He. The calculation could probably be improved by use of a better effective interaction and increasing shell model space. With the use of faster computer with large memories, the authors are in hope of calculation in spsd shell-model space

221

Direct interband dipole-transition selection rules for the O/sub h//sup 3/ space-group compounds  

Energy Technology Data Exchange (ETDEWEB)

The irreducible representations associated with states of dipole symmetry have been calculated for the space groups O/sub h//sup 3/, the space group with the correct symmetry for A-15 phase compounds. Also assembled are the character tables of the O/sub h/3 group. Thus all thedirect interband dipole-transition selection rules for A-15 compounds can easily be determined.

1983-07-01

222

Development and evaluation for passive dosimeter using several solid dosimeters  

International Nuclear Information System (INIS)

Passive dosimeters for personal and area radiation monitor in space have been developed mainly for dosimetry in low-earth-orbit (LEO) radiation environments of Space Shuttles and the International Space Station. The responses of several dosimeters have been evaluated by heavy ions and also its variation for individual dosimeter element. (author)

2005-05-01

223

Dendrite spacings in directionally solidified superalloy PWA-1480  

Energy Technology Data Exchange (ETDEWEB)

Primary dendrite spacings and side-branch coarsening kinetics were examined in specimens of the single-crystal multicomponent commercial superalloy PWA-1480, which were directionally solidified in a psoitive thermal gradient. The experimentally observed dependence of primary dendrite spacings and side-branch coarsening kinetics on growth rate and thermal gradient were in agreement with the behavior predicted by analytical models developed for binary alloys. (orig.).

1991-02-01

224

An S-brane solution with acceleration and small enough variation of G  

CERN Document Server

An S-brane solution with two non-composite electric branes and a set of l scalar fields is considered. The intersection rule for branes corresponds to the Lie algebra A_2. The solution contains five factor spaces with the fifth one interpreted as ``our'' 3-dimensional space. It is shown that there exists a time interval where accelerating expansion of ``our'' 3-dimensional space is compatible with small enough value of effective gravitational ``constant'' variation.

2007-01-01

225

Space power systems prelaunch integration  

International Nuclear Information System (INIS)

The sequence of events from the assembly of a space nuclear power system to its integration in the Space Shuttle Transportation System (STS) is considered. First, the sequence followed for SNAP-10A, the only free world space reactor electric power system ever launched and operated in space, is reviewed. Before shipment, the SNAP-10A reactor was raised to operating temperature using electrically supplied heat and operated at low power for control calibration. Next we discuss shipment to the launch site, a phase that is critical because of the potential for various accidents. Once the power system arrives at the launch site, the processing sequence is performed. This sequence includes checkout, mating with the payload or upper stage launch vehicle, and integration into the STS.

226

Quantum probabilities: an information-theoretic interpretation  

CERN Document Server

This Chapter develops a realist information-theoretic interpretation of the nonclassical features of quantum probabilities. On this view, what is fundamental in the transition from classical to quantum physics is the recognition that \\emph{information in the physical sense has new structural features}, just as the transition from classical to relativistic physics rests on the recognition that space-time is structurally different than we thought. Hilbert space, the event space of quantum systems, is interpreted as a kinematic (i.e., pre-dynamic) framework for an indeterministic physics, in the sense that the geometric structure of Hilbert space imposes objective probabilistic or information-theoretic constraints on correlations between events, just as the geometric structure of Minkowski space in special relativity imposes spatio-temporal kinematic constraints on events. The ...

2010-01-01

227

Automatic Extraction of Open Space Area from High Resolution Urban Satellite Imagery  

CERN Document Server

In the 21st century, Aerial and satellite images are information rich. They are also complex to analyze. For GIS systems, many features require fast and reliable extraction of open space area from high resolution satellite imagery. In this paper we will study efficient and reliable automatic extraction algorithm to find out the open space area from the high resolution urban satellite imagery. This automatic extraction algorithm uses some filters and segmentations and grouping is applying on satellite images. And the result images may use to calculate the total available open space area and the built up area. It may also use to compare the difference between present and past open space area using historical urban satellite images of that same projection

2011-01-01

228

FY2007 Oak Ridge National Laboratory Annual Progress Report for the Power Electronics and Electric Machinery Program  

Energy Technology Data Exchange (ETDEWEB)

The U.S. Department of Energy (DOE) and the U.S. Council for Automotive Research (composed of automakers Ford, General Motors, and Chrysler) announced in January 2002 a new cooperative research effort. Known as 'FreedomCAR' (derived from 'Freedom' and 'Cooperative Automotive Research'), it represents DOE's commitment to developing public/private partnerships to fund high-risk, high-payoff research into advanced automotive technologies. Efficient fuel cell technology, which uses hydrogen to power automobiles without air pollution, is a very promising pathway to achieving the ultimate vision. The new partnership replaces and builds upon the Partnership for a New Generation of Vehicles initiative that ran from 1993 through 2001. The Advanced Power Electronics and Electric Machines (APEEM) subprogram within the FreedomCAR and Vehicle Technologies Program provides support and guidance for many cutting-edge automotive ...

2007-10-01

229

Zinc air battery development for electric vehicles  

Energy Technology Data Exchange (ETDEWEB)

This document reports the progress and accomplishments of a 16 month program to develop a rechargeable zinc-air battery for electric vehicle propulsion, from October 1988 through January 1990. The program was the first stage in the transition of alkaline zinc electrode technology, invented at Lawrence Berkeley Laboratory, to private industry. The LBL invention teaches the use of a copper metal foam substrate for the zinc electrode, in combination with forced convection of electrolyte through the foam during battery operation. Research at LBL showed promise that this approach would avoid shape change (densification and dendrite growth), the primary failure mode of this electrode. The program comprised five tasks; (1) cell design, (2) capacity maximization, (3) cycle testing, (4) materials qualification, and (5) a cost/design study. The cell design contemplates a plate and frame stack, with alternating zinc and oxygen electrode frame assemblies between rigid end ...

1990-05-01

230

Transhipment operations at Huizhou oil field by FPSO Munin; Overslag operaties op Huizhou olieveld met FPSO Munin  

Energy Technology Data Exchange (ETDEWEB)

At the Huizhou oil field in China the FPSO Munin of Bluewater completely relies on five computer controlled propulsion screws to position itself, a so-called Dynamic Positioning (DP) system. In this article report is given of training given to the crew of the FPSO Munin. A floating production, storage and offloading (FPSO) unit is a floating vessel used by the offshore industry for the processing and storage of oil and gas. [Dutch] Op het Huizhou oileveld in China vertrouwt de FPSO (floating production, storage and offloading unit) Munin van Bluewater uitsluitend op een vijftal computergestuurde voorstuwingsschroeven om zichzelf in positie te houden, een zogenaamd Dynamisch Positionering (DP) systeem. In dit artikel wordt verslag gedaan van en uitleg gegeven over trainingen die zijn gegeven aan de bemanning van de FPSO Munin.

2010-07-15

231

Trade studies on Integrated Solar Upper Stage (ISUS) systems  

Energy Technology Data Exchange (ETDEWEB)

The Integrated Solar Upper Stage (ISUS) Program at the USAF Phillips Laboratory is directed at demonstrating a solar bimodal power and propulsion system for military applications. Trades were performed to examine the potential performance of the ISUS stage combined with the proposed LLV-3 launch vehicle. Variation in ISUS thermal power directly affects the trip time from LEO to GEO. These variations can be altered by changing average propellant temperature raising or lowering the average specific impulse. If the ISUS system is sized for the spacecraft`s electrical power requirements, this can result in long trip times for high mass satellites with low electrical power requirements. The ISUS can be sized, however, for a suitable thermal power to allow more rapid trip times with minimum impact on delivered mass. Such a system can place significantly more payload in GEO than a solid chemical stage. The mass advantages of the ISUS increase as electrical power ...

1995-12-31

232

MAN B&W Diesel extends dual-fuel engine range up to 16 MW  

Energy Technology Data Exchange (ETDEWEB)

In 1995, MAN B&W Diesel launched a dual-fuel version of the successful L + V (in-line and vee) configurations of the 32/40 diesel engine series, covering a power range between 2.4 and 7.2 MW. In 1996, the company is launching a dual-fuel version of the L + V 48/60 engine series, moving the power range of dual-fuel engines to 16.2 MW. With its new dual fuel type 32/40 DG and 48/60 DG engines, MAN B&W Diesel has designed prime movers offering a high efficiency at low operating costs, while simultaneously meeting the most stringent NO{sub x} emission limits without any exhaust gas after-treatment. These engines are based on the successful HFO-operated four-stroke diesel engines. They offer environment-friendly and, operating at high mean effective pressures, simultaneously cost effective propulsion alternatives, especially if natural gas is used as a fuel. Extension of the compatibility to permit further kinds of gas such as sewage gas to be used is being ...

1996-04-01

233

Load calculation and system evaluation for electric vehicle climate control  

Energy Technology Data Exchange (ETDEWEB)

This paper presents an analysis of the applicability of alternative systems for electric vehicle (EV) heating and air conditioning (HVAC). The paper consists of two parts. The first part is a cooling and heating load calculation for electric vehicles. The second part is an evaluation of several systems that can provide the desired cooling and heating in EVs. These systems are ranked according to their overall weight The overall weight is calculated by adding the system weight and the weight of the battery necessary to provide energy for system operation. The system with the minimum overall weight is considered to be the best, because minimum vehicle weight decreases the energy required for propulsion, and therefore increases the vehicle range. Three systems are considered as the best choices for EV HVAC. These are, vapor compression, ice storage and adsorption systems. These systems are evaluated, including calculations of system weight, system volume, and COP. The ...

1994-09-12

234

Harmonics in power systems of ships with electrical propulsion drives. Comparison between different converters  

Energy Technology Data Exchange (ETDEWEB)

In this report the effects of harmonics in marine power systems is discussed and a comparison is given between the most typical converter types, including pulse width modulated drives, load commutated inverters and cycloconverters. The effect of harmonic distortion on the power system equipment and loads is first briefly discussed. Special attention is given to the circumstances in the low voltage distribution system, where general load equipment is connected. In addition to the total harmonic distortion the effect of voltage deviation to the supply quality is also considered. The origin of harmonics in the load currents of the three converter types is then considered. The differences between the converters are outlined, and the most typical spectra are presented. The possible means for reducing the harmonic distortion are also studied. The solutions considered are the increasing of the short circuit level, the use of harmonic filters and the increasing of the pulse number. In the case ...

1996-11-01

235

HISTORICAL AMERICAN ENGINEERING RECORD - IDAHO NATIONAL ENGINEERING AND ENVIRONMENTAL LABORATORY, TEST AREA NORTH, HAER NO. ID-33-E  

Energy Technology Data Exchange (ETDEWEB)

Test Area North (TAN) was a site of the Aircraft Nuclear Propulsion (ANP) Project of the U.S. Air Force and the Atomic Energy Commission. Its Cold War mission was to develop a turbojet bomber propelled by nuclear power. The project was part of an arms race. Test activities took place in five areas at TAN. The Assembly & Maintenance area was a shop and hot cell complex. Nuclear tests ran at the Initial Engine Test area. Low-power test reactors operated at a third cluster. The fourth area was for Administration. A Flight Engine Test facility (hangar) was built to house the anticipated nuclear-powered aircraft. Experiments between 1955-1961 proved that a nuclear reactor could power a jet engine, but President John F. Kennedy canceled the project in March 1961. ANP facilities were adapted for new reactor projects, the most important of which were Loss of Fluid Tests (LOFT), part of an international safety program for commercial power reactors. Other projects ...

2005-02-01

236

GeoSAR program: IFSAR validation and terrain classification from polarimetry  

Science.gov (United States)

The GeoSAR (geographic synthetic aperture radar) program is a Defense Advanced Research Projects Agency (DARPA) sponsored program organized in cooperation with the Jet Propulsion Laboratory (JPL) and the California Department of Conservation. Some aspects of the program have been existent for almost two years. The technical goal of the program has been the development of rapid-mapping radar technologies, and has now, as its principal challenge, the development of a capability for terrain mapping under foliage. In this paper, we discuss validation of current technology and examine the utility of data products currently produced by the Environmental Research Institute of MIchigan's (ERIM) IFSARE, JPL's TOPSAR, and JPL's AIRSAR. We find that ERIM's X-band IFSARE system produces elevation maps to better than 2-m accuracy. Based on this we determine that TOPSAR elevation maps are accurate to at least 5 m. We also demonstrate the utility of JPL's AIRSAR's L-band radar ...

1996-06-01

237

Fly on the wings of the sun - a study of solar-powered aircraft  

Energy Technology Data Exchange (ETDEWEB)

Solar High Altitude Powered Platform (Solar HAPP) aircraft are unmanned remote sensing vehicles designed for cruises lasting up to one year at 20-km altitude, while carrying up to 250 pounds of cameras and electrooptic sensors in an underslung payload pod. It is anticipated that real time IR and UV images of earth features may be more inexpensively and accurately obtained by this means than by the conventional geosynchronous earth resources satellites. Solar HAPPs, with wing spans of over 300 ft and weights of only 2000 lb, require ultralight composite structures with external wire bracing. Solar cells will cover both sides of the vertical wing stabilizers and wing tips, which hinge up in daytime to capture the maximum amount of sunlight. A 15-hp electric propulsion unit drives a low-rpm, large diameter propeller; power will be derived from the solar cells diurnally, and from hydrogen-oxygen fuel cells nocturnally. The fuel gases will be generated in a water ...

1985-06-01

238

Feasibility of an antiproton catalyzed fission fragment rocket  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this project was to investigate the feasibility of an antiproton catalyzed fission fragment rocket (FFR). The FFR is characterized by the extraction of fission fragments from the fissile fuel, and the utilization of their kinetic energy for thrust generation. A significant drawback to previous FFR designs was the requirement to maintain a critical nuclear pile as the fission fragment source. The author examined the possibility of replacing the critical pile with a sub-critical pile driven by antiprotons. Recent experiments have revealed that antiprotons stimulate highly energetic fissions in {sup 238}U, with a neutron multiplicity of 13.7 neutrons per fission. This interaction was used as a throttled neutron source. The pile consisted of layers of fissile coated fibers which are designed to allow fission fragments to escape them, where the fragments collide with a fluid. The heated fluid is then ejected from the rocket to provide thrust. The calculations performed ...

1992-03-01

239

Experimental electrochemical capacitor test results  

Energy Technology Data Exchange (ETDEWEB)

Various electrochemical capacitors (ultracapacitors) are being developed for hybrid vehicles as candidate power assist devices for the fast response engine. The primary functions of the ultracapacitor are to level the dynamic power loads on the primary propulsion device and recover available energy from regenerative breaking during off-peak power periods. Ultracapacitors show promise toward being able to accept high regenerative pulses while exhibiting very high cycle life. This paper will present test data from selected US Department of Energy (DOE) supported ultracapacitor projects designed to meet the fast response engine requirements. Devices containing carbon, conducting polymers, and metal oxide electrode materials in combination with aqueous or organic electrolytes are being supported by the DOE. This paper will present and discuss testing data obtained from recent prototype capacitors supplied by Maxwell Energy Products, Inc., SAFT America, Inc., Federal ...

1997-11-01

240

Development of a 1200 KW/CYL low pressure dual fuel engine for LNG carriers  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the design and feasibility tests of a 570 mm bore 4 stroke low pressure (L.P.) dual fuel engine rated at 20.9 bar BMEP meant for the propulsion of LNG carriers. The basic design features which are to be in accordance with classification societies safety rules are described: individual electro hydraulic valves located in the air manifold ducts, pilot injection, monitoring system etc. The engine capability to burn variable liquid/gas fuel proportions have been investigated with diesel oil and heavy fuel and possible running zones are defined. This ensures the possibility of the engine to cope with the different boil off gas quantity emanating from the ship`s tank during her loaded - and ballast - journeys. With the very lean setting of this engine, no adverse influence of the high ash lube-oil additives were found during the tests. Further tests are necessary to confirm that possible more significant fouling of the combustion chamber is still ...

1998-12-31

241

Consideration of some fundamental erosion processes encountered in hypervelocity electromagnetic propulsion  

Energy Technology Data Exchange (ETDEWEB)

Experimental and theoretical research has been conducted jointly at the Livermore and Los Alamos National laboratories on dc electromagnetic railgun Lorentz accelerators. Pellets weighing a few grams to tens of grams have been launched at velocities up to better than 11 km/s. The research is addressed to attaining repeated launches of samples at hypervelocity in target impact experiments. In these experiments, shock-induced pressures in the tens of megabars range are obtained for high pressure equation-of-state research. Primary energy sources of the order of several hundred kJ to a MJ and induction currents of the order of 1 or more MA are necessary for these launches. Erosion and deformation of the conductor rails and the accelerated sample material are continuing problems. The heating, stress, and erosion resulting from simultaneous imposition of rail induction current, dense plasma (armature) interaction, current distribution, magnetic field stresses and projectile/rail contact ...

1982-09-30

242

A dynamic model of a locomotive diesel engine and electrohydraulic governor  

Energy Technology Data Exchange (ETDEWEB)

As part of a comprehensive simulation of a prototype locomotive propulsion system, a detailed model has been developed which predicts the dynamic response of an experimental 2-stroke, turbocharged and intercooled diesel engine. Engine fueling and brake torque are computed from regression equations derived from an extensive data base. Corrections are applied to the calculated steady-state torque to account for dynamic deviations of in-cylinder trapped air-fuel ratio from the steady-state value. The engine simulation accurately represents the operation of the turbo-charger, which is gear-driven at low turbocharger speeds, and freewheels through an overrunning clutch when exhaust energy accelerates the turbocharger beyond its geared speed. Engine fueling level, ie, rack, is determined from a dynamic simulation of an electrohydraulic governor which responds to the difference between the desired and the actual engine speeds. The governor representation includes (1) ...

1988-01-01

243

MHV diagrams in twistor space and the twistor action  

CERN Document Server

MHV diagrams give an efficient Feynman diagram-like formalism for calculating gauge theory scattering amplitudes on momentum space. Although they arise as the Feynman diagrams from an action on twistor space in an axial gauge, the main ingredients were previously expressed only in momentum space and momentum twistor space. Here we show how the formalism can be elegantly derived and expressed entirely in twistor space. This brings out the underlying superconformal invariance of the framework (up to the choice of a reference twistor used to define the axial gauge) and makes the twistor support transparent. Our treatment is largely independent of signature, although we focus on Lorentz signature. Starting from the N=4 super-Yang-Mills twistor action, we obtain the propagator for the anti-holomorphic Dolbeault-operator as a delta function imposing collinear support with the reference ...

2011-01-01

244

Estimation of parameters affecting the uptake of sup(99m)Tc-methylenediphosphonate in rat femur with model simulation  

Energy Technology Data Exchange (ETDEWEB)

The uptake of sup(99m)Tc-methylenediphosphonate (MDP) in different parts of rat femur was simulated using a local three-space model for tracer transfer. The model consisted of bone blood, bone ECF-space and space for tracer deposition. The measured sup(99m)Tc-MDP concentration in the systemic blood and the local bone blood flow measured by /sup 131/I-macroaggregated albumin microspheres were used as input parameters. The measured blood flow values were 6.3, 3.1 and 15.3 ml/100 g/min for proximal, middle and distal femur, respectively. the model parameters that gave the best fit to measured sup(99m)Tc-MDP uptake curves in computer simulation showed that bone blood flow, volume of ECF-space, permeability surface area product and accretion constant from ECF-space to space for tracer deposition were highest in distal and lowest in middle femur. The values ...

1985-01-01

245

Estimation of parameters affecting the uptake of sup(99m)Tc-methylenediphosphonate in rat femur with model simulation  

International Nuclear Information System (INIS)

The uptake of sup(99m)Tc-methylenediphosphonate (MDP) in different parts of rat femur was simulated using a local three-space model for tracer transfer. The model consisted of bone blood, bone ECF-space and space for tracer deposition. The measured sup(99m)Tc-MDP concentration in the systemic blood and the local bone blood flow measured by "1"3"1I-macroaggregated albumin microspheres were used as input parameters. The measured blood flow values were 6.3, 3.1 and 15.3 ml/100 g/min for proximal, middle and distal femur, respectively. the model parameters that gave the best fit to measured sup(99m)Tc-MDP uptake curves in computer simulation showed that bone blood flow, volume of ECF-space, permeability surface area product and accretion constant from ECF-space to space for tracer deposition were highest in distal and lowest in middle femur. The values corresponded ...

246

Dissipation and entropy production in open quantum systems  

Energy Technology Data Exchange (ETDEWEB)

A microscopic description of an open system is generally expressed by the Hamiltonian of the form: H{sub tot} = H{sub sys} + H{sub environ} + H{sub sys-environ}. We developed a microscopic theory of entropy and derived a general formula, so-called 'entropy-Hamiltonian relation' (EHR), that connects the entropy of the system to the interaction Hamiltonian represented by H{sub sys-environ} for a nonequilibrium open quantum system. To derive the EHR formula, we mapped the open quantum system to the representation space of the Liouville-space formulation or thermo field dynamics (TFD), and thus worked on the representation space L := H x H-tilde, where H denotes the ordinary Hilbert space while H-tilde the tilde Hilbert space conjugates to H. We show that the natural transformation (mapping) of nonequilibrium open quantum systems is accomplished within the theoretical ...

2010-11-01

247

The entropic boundary law in BF theory  

International Nuclear Information System (INIS)

We compute the entropy of a closed bounded region of space for pure 3d Riemannian gravity formulated as a topological BF theory for the gauge group SU(2) and show its holographic behavior. More precisely, we consider a fixed graph embedded in space and study the flat connection spin network state without and with particle-like topological defects. We regularize and compute exactly the entanglement for a bipartite splitting of the graph and show it scales at leading order with the number of vertices on the boundary (or equivalently with the number of loops crossing the boundary). More generally these results apply to BF theory with any compact gauge group in any space-time dimension.

2009-01-11

248

The Geometry of Stable Quotients in Genus One  

CERN Document Server

Stable quotient spaces provide an alternative to stable maps for compactifying spaces of maps. When the target is projective space and the domain curve has genus 1, these are smooth proper Deligne-Mumford stacks. In this paper we study the associated coarse moduli schemes. We show these schemes are projective, rationally connected and have Picard number 2. Then we give generators for the Picard group, compute the canonical divisor, and the cones of ample and effective divisors. In certain cases, we also give a closed formula for the Poincar\\'{e} polynomial.

2011-01-01

249

Simplifying Schmidt number witnesses via higher-dimensional embeddings  

CERN Document Server

We apply the generalised concept of witness operators to arbitrary convex sets, and review the criteria for the optimisation of these general witnesses. We then define an embedding of state vectors and operators into a higher-dimensional Hilbert space. This embedding leads to a connection between any Schmidt number witness in the original Hilbert space and a witness for Schmidt number two (i.e. the most general entanglement witness) in the appropriate enlarged Hilbert space. Using this relation we arrive at a conceptually simple method for the construction of Schmidt number witnesses in bipartite systems.

2004-01-01

250

Scalar field cosmology in three-dimensions  

Energy Technology Data Exchange (ETDEWEB)

We study an analytical solution to the Einstein's equations in 2 + 1-dimensions. The space-time is dynamical and has a line symmetry. The matter content is a minimally coupled, massless, scalar field. Depending on the value of certain parameters, this solution represents three distinct space-times. The first one is at space-time. Then, we have a big bang model with a negative curvature scalar and a real scalar field. The last case is a big bang model with event horizons where the curvature scalar vanishes and the scalar field changes from real to purely imaginary. (author)

2001-09-01

251

Group classification of the Sachs equations for a radiating axisymmetric, non-rotating, vacuum space-time  

CERN Document Server

We carry out a Lie group analysis of the Sachs equations for a time-dependent axisymmetric non-rotating space-time in which the Ricci tensor vanishes. These equations, which are the first two members of the set of Newman-Penrose equations, define the characteristic initial-value problem for the space-time. We find a particular form for the initial data such that these equations admit a Lie symmetry, and so defines a geometrically special class of such spacetimes. These should additionally be of particular physical interest because of this special geometric feature.

2006-01-01

252

Electromagnetic form factors of nucleons with QCD constraints: Systematic study of space- and time-like regions  

Science.gov (United States)

Elastic electromagnetic form factors of nucleons are investigated for both the time-like and the space-like momenta by using the unsubtracted dispersion relation with QCD constraints. It is shown that the calculated form factors reproduce the experimental data reasonably well; they agree with recent experimental data for the neutron magnetic form factors for the space-like data obtained by the CLAS Collaboration and are compatible with the ratio of the electric and magnetic form factors for the time-like momentum obtained by the BABAR Collaboration.

2010-04-15

253

Discrete Euclidian Spaces: a starting point toward the discretization of mathematics  

CERN Document Server

Discrete Euclidian Spaces (DESs) are the beginning of a journey without return towards the discretization of mathematics. Important mathematical concepts- such as the idea of number or the systems of numeration, whose formal definition is currently independent of Euclidean spaces -have in the Isodimensional Discrete Mathematics (IDM) their roots in the DESs. This mathematics, which arises largely from the discretization of traditional mathematics, presents its foundations and concepts differently from the orthodox way, so at first glance it may seem that the IDM could be an exotic tool, or perhaps just "a simple curiosity." However, the IDM dis-crete approaches have a great theoretical repercussion on traditional mathematics.

2011-01-01

254

An assessment of the building sector efficiency resource for the Town of Handlova  

Energy Technology Data Exchange (ETDEWEB)

Purpose of this assessment for this town in the Slovak Republic is to develop information on the building sector energy efficiency and improvement potential for use by town management to support decisions on providing energy services to Handlova citizens. Objectives were to characterize baseline space and water heat energy use and efficiency improvement potential in the residential and nonresidential building sectors. Intention was to identify major areas of efficiency improvement potential and cost-effectiveness. Four levels of energy and fuel prices were used. A significant efficiency resource exists in the space and water heating end uses in these building sectors; it amounts to 42% of the total building sector space and water heat energy consumption.

1995-10-01

255

APSIS - an Artificial Planetary System in Space to probe extra-dimensional gravity and MOND  

CERN Document Server

A proposal is made to test Newton's inverse-square law using the perihelion shift of test masses (planets) in free fall within a spacecraft located at the Earth-Sun L2 point. Such an Artificial Planetary System In Space (APSIS) will operate in a drag-free environment with controlled experimental conditions and minimal interference from terrestrial sources of contamination. We demonstrate that such a space experiment can probe the presence of a "hidden" fifth dimension on the scale of a micron, if the perihelion shift of a "planet" can be measured to sub-arc-second accuracy. Some suggestions for spacecraft design are made.

2006-01-01

256

A viable model of locally anisotropic space-time and the Finslerian generalization of the relativity theory  

Energy Technology Data Exchange (ETDEWEB)

The work is devoted to the construction of a viable of locally anisotropic, i.e. Finslerian, space-time and to the generalization, on this basis, of the relativistic theory of gravitation. Arguments in favour of this model are considered. From physical considerations the concrete form of the Finslerian metric has been reconstructed and within the framework of the correspondence principle a formalism of the theory has been developed. The approach suggested is aimed at developing unified gauge theories of all fundamental interactions. Much attention is given to the nontrivial physical manifestations of local space anisotropy and to the possibility of its experimental detection. (orig.)

1994-01-01

257

this issue NASA Cloud Computing Platform: Nebula  

Science.gov (United States)

National Aeronautics and Space Administration. Issue 2. June 2010 this issue. Nebula: Cloud Computing p.1. Better Business with EA p.2 ...

258

resignas - Johnson Space Center - NASA  

Science.gov (United States)

Feb 14, 1992 ... Almond Magic Chef elec cooktop, 30" x 21",. Woodworking tools, chisels, clamps, worm. '89 Toyota PU chrome bumper, $75; Neiman ...

259

chapter 5 - NASA's History Office  

Science.gov (United States)

Ever-present water vapor and dust distort or block incoming radiations. ... were among the first scientific sensors to be attached to the earliest space rockets. ...

260

Why the United States Must Deploy a National Missile ...  

Science.gov (United States)

... transItion to more capable space-based interceptors as ... ten wtth bmlogtcal, and thirty with chemical weapons. ... are becoming the weapon of choice ...

2011-05-14

261

What are $E_{\\infty}$ ring spaces good for?  

CERN Document Server

Infinite loop space theory, both additive and multiplicative, arose largely from two basic motivations. One was to solve calculational questions in geometric topology. The other was to better understand algebraic K-theory. The Adams conjecture is intrinsic to the first motivation, and Quillen's proof of that led directly to his original, calculationally accessible, definition of algebraic K-theory. In turn, the infinite loop understanding of algebraic K-theory feeds back into the calculational questions in geometric topology. For example, use of infinite loop space theory leads to a method for determining the characteristic classes for topological bundles (at odd primes) in terms of the cohomology of finite groups. We explain just a little about how all that works, focusing on the central role played by E infinity ring spaces.

2009-01-01

262

Welcome The National Aeronautics and Space Administration (NASA) is  

Science.gov (United States)

Mar 8, 2006 ... Some examples of leave options are annual leave, sick leave, .... (FERS). This three-tier system combines social security, a basic annuity ...

263

Volume IIr - NASA Technical Report Server (NTRS)  

Science.gov (United States)

f4. HRS. 65. 119 HRS. Figure 2-39. Space Processing Shared Flows ..... Learning Curve: An 80 percent learning curve will be used to extrap ...

264

United States Space Activities - NASA  

Science.gov (United States)

Mission losses were incurred by an early warning satellite and a Milstar-2 communications satellite when their launch vehicles malfunctioned, the first, ...

265

Travel of Pollen in Experimental Raceways in the Endangered Texas Wild Rice (Zizania texana)  

Science.gov (United States)

... including exotic species such as Hydrilla verticellata (hydrilla), Hygrophila polysperma (hygrophila), Cryptocoryne beckettii (water trumpet), leaving little space ... ...

266

Transforming Clinic Environments into Information Workspaces for Patients  

UK PubMed Central (United Kingdom)

Although clinic environments are a primary location for exchanging information with clinicians, patients experience these spaces as harsh environments to access, use, exchange, and manage information....Full Text Available

2010-01-01

267

Tours of NOAA Boulder and ESRL  

Science.gov (United States)

Research Center last approximately 1.5 hours and include stops at the Space Weather Prediction Center, ESRL Global Monitoring Division for information on the carbon dioxide...

2011-08-26

268

The Shifty Nature of Grains  

Science.gov (United States)

... Astronomy & Space Biology Chemistry & Materials Computing Earth & Environment Education ... Materials Research Center at the University of Chicago, one of nearly 30 NSF-supported Materials ...

269

The Natural Statistics of Audiovisual Speech  

UK PubMed Central (United Kingdom)

Humans, like other animals, are exposed to a continuous stream of signals, which are dynamic, multimodal, extended, and time varying in nature. This complex input space must be transduced and sampled...Full Text Available

2009-07-01

270

The Limits of Spacepower  

Science.gov (United States)

... to light-light a laser or directed energy weapon would ... space-based components... .the most likely threats are direct ascent anti-satellite weapons; ...

2001-05-18

271

The Deep Space Network Progress Report 42-39 - NASA Technical ...  

Science.gov (United States)

C. Learning Curve. The learning curve concept has long been recognized and ...... F4. TERMIA. S - STATION EQUIPMENT. V - VLBI VALIDATION EQUIPMENT ...

272

Tensors, spinors, and functions on the unit sphere  

International Nuclear Information System (INIS)

A representation of tensors and spinors at a point of space-time as spin and conformally weighted functions on the unit sphere is derived. Methods for performing algebraic operations on tensors and spinors in this representation are discussed. (author).

273

Target space duality I: general theory  

Energy Technology Data Exchange (ETDEWEB)

We develop a systematic framework for studying target space duality at the classical level. We show that target space duality between manifolds M and M-tilde arises because of the existence of a very special symplectic manifold. This manifold locally looks like MxM-tilde and admits a double fibration. We analyze the local geometric requirements necessary for target space duality and prove that both manifolds must admit flat orthogonal connections. We show how abelian duality, nonabelian duality and Poisson-Lie duality are all special cases of a more general framework. As an example we exhibit new (nonlinear) dualities in the case M=M-tilde=R{sup n}.

2000-09-25

274

TAQL: A Problem Space Tool for Expert System Development.  

Science.gov (United States)

... Missionaries and cannibals [MaC] (Newell, McDermott and Forgy, 1977, p. 63): Three missionaries and three cannibals must cross a river in a two ...

1992-05-01

275

System performance of a solar thermophotovoltaic system for space and terrestrial application  

Energy Technology Data Exchange (ETDEWEB)

Solar thermophotovoltaics (STPV) potentially have high system power efficiency together with other attractive attributes for both space and terrestrial applications. This paper presents a summary of work that has been conducted by NASA Lewis Research Center (LeRC) and McDonnell Douglas Aerospace (MDA). The paper discusses analytical modeling and subsystem testing, laboratory, and field testing that has been conducted. The features which make solar thermophotovoltaics attractive for both space and terrestrial applications are discussed. Based upon these investigations and the work of others, a conceptual design has been formulated, and an estimate of system performance is presented. This estimate indicates a solar thermophotovoltaics system can result in competitive energy costs for the utility electrical market applications and a high power-to-mass ratio for space power applications.

1995-12-31

276

Sun rises on station era - Johnson Space Center - NASA  

Science.gov (United States)

Dec 4, 1998 ... throwing a single switch to as complex as the Spartan deploy and retrieve. ...... The camera, called the Acousto-Optic ...

277

State Space Partitioning Methods for Solving a Class of ...  

Science.gov (United States)

... LIFO queue descipline outperforms FIFO in ... We consider here the stochastic network system ... All-terminal Undirected Rational Network Reliability ...

1993-05-01

278

Space shuttle Discovery scheduled to launch Aug. 25 from Kennedy ...  

Science.gov (United States)

Aug 20, 2009 ... gratings, used to precisely determine the energies of incoming ..... The rocket is wired throughout with more than 700 sensors ...

279

Space Weather Prediction Center Education and Outreach  

Science.gov (United States)

Education resources dealing with solar-terrestrial physics, solar effects, solar radiation, etc. Includes links to short reference papers on subjects ... ...

280

Space Science - NASA Headquarters  

Science.gov (United States)

Canada will provide telescope baffles and fine error sensor assemblies. ..... ( Ongoing) Flight tests aboard sounding rockets and balloon planned for FY 1995. .... the effects of incoming energetic particles and solar radiation on the ...

281

STS067-703D-090 Kinshasa ... - Earth from Space - Image Information  

Science.gov (United States)

... rivers of the world, the Zaire is not an efficient transportation link because of many rapids and falls to negotiate between Kinshasa and the port city of Matadi. ...

282

SPACE STATION INTEGRATED WALL DESIGN AND PENETRATION  

Science.gov (United States)

screens of fine wire was placed between the gun barrel and the panel to determine whether the gun performance was repeatable. The transducers were placed ...

283

SPACE ACT AGREEMENT FOR COTS - NASA  

Science.gov (United States)

F4. Totai Cost by System. Two K-l's will be built to assure successful COTS Demos. ...... has started that learning curve.with the Falcon 1 first stage. ...

284

SECURITY FOR MULTIMEDIA SPACE DATA ... - NASA Technical Reports Server  

Science.gov (United States)

Recently SSBRP network security planning was formalized with the production of several .... The SSBRP Network Security. Policy was written ...

285

Robonaut 2 Makes First Motions on Station  

National Aeronautics and Space Administration (NASA)

Robonaut 2 goes through a series of tests aboard the International Space Station, including its first motions on the orbital outpost. n

2011-10-14

286

Remote Sensing Tutorial ... - The Remote Sensing Tutorial - NASA  

Science.gov (United States)

The first space photographs were obtained from V-2 rockets fired upwards from the ..... Some fraction of the incoming solar radiation is reflected towards a sensor ...

288

ROUNDUP NAsA - Johnson Space Center - NASA  

Science.gov (United States)

Jul 3, 1975 ... Elect cooktop, GE, coppertone, xlnt. Used flute, Lyle, 2831. The Roundup is an official publication of the National. Aeronautics ...

289

ROUNDUP - Johnson Space Center - NASA  

Science.gov (United States)

Sep 12, 1975 ... POCKET CALCULATORS. Jose P. Olivares 35, Robert B. Clowns and ... of pocket calculators and has an- Washington to arrive by Nov. 20. ...

290

Publication Year - NASA Technical Reports Server  

Science.gov (United States)

Abstract: Inertial navigation error analysis of space vehicle during reentry. NASA Center: Ames Research Center Publication Year: 1963 ...

291

Printed product downloads - NASA Space Place  

Science.gov (United States)

Aug 26, 2011 ... The main article on the back of the poster explains star evolution in very simple terms (including the fate of our own Sun), and how a planetary ...

292

PolyRAD Space Radiation Shield for Commercial-Off-The  

Science.gov (United States)

Defense satellites, including the next generation GPS and MILSTAR, continue to require TID well above that of most COTS silicon. ...

293

Particle-Gas Dynamics and Primary Accretion - Space Science and ...  

Science.gov (United States)

the revealed stage of T Tauri star evolution, is only a mere shadow of its former self. Once primary accretion starts, one has the (poorly quantified) ...

294

National Military Strategy to Combat Weapons of Mass ...  

Science.gov (United States)

... and regional land, sea, air, and space-based systems, and ... means of delivery of weapons where such ... a separable and divisible part of the weapon. ...

2006-02-13

295

NRAO: Press Releases  

Science.gov (United States)

Evolution in Space Radio Telescopes Reveal Youngest Stellar Corpse Gas Clouds in Whirlpool Galaxy Yield Important Clues Supporting Theory on Spiral Arms Starbust-driven Winds...

2011-10-09

296

NASA/Marshall Space Flight Center Cooperative Education Program  

Science.gov (United States)

Co-op students hired since December 3, 1983 will be covered under FERS. ... amount of sick leave that can be accumulated for use in succeeding years. 11. ...

297

NASA's Next Major Space Observatory - Flight Projects - NASA  

Science.gov (United States)

of Earth Science data and information management capabilities. Dale Schulz/400 . For your exceptional achievement in leading the joint LaRC/GSFC team in ...

298

NASA partners with teacher institute NASA strives to improve computers  

Science.gov (United States)

of the digital hearing aid technology that led to the cochlear implant. Former. Marshall Space Flight Center engineers. John Richardson and Joseph Howard ...

299

NASA Waterjet ... - Technology Transfer Program - Success Stories  

Science.gov (United States)

A waterjet coating-removal system was developed at NASA's Marshall Space Flight Center in Huntsville, Ala., to remove thermal protective coatings from the ...

300

NASA Sets Launch Dates for Remaining Space Shuttle Missions  

Science.gov (United States)

Jul 7, 2008 ... HOUSTON -- Following a detailed, integrated assessment, NASA selected ... in the center that provides a 360-degree view around the station. ...

301

NASA Project Inducted Into Space Technology Hall of  

Science.gov (United States)

Apr 9, 2003 ... Adam Kissiah Jr., a retired KSC engineer, will be honored for his development of the digital hearing aid technology that led to the cochlear ...

302

NASA Direct! - Kennedy Space Center - Home - NASA  

Science.gov (United States)

Aug 21, 2003 ... Her research interests have included hot stars, colliding stellar winds, binary star evolution and evolved stellar companions. ...

303

NASA - Pico-Satellite Solar Cell Experiment (PSSC)  

Science.gov (United States)

Jun 10, 2011 ... The PSSC is a picosatellite designed to test the space environment by providing a testbed to gather data on new solar cell technologies.

304

NASA - Archive  

Science.gov (United States)

equipping the trio of SPHERES on the space station with a Nexus(tm) S handset made by Samsung Electronics and powered by Google's Android(tm) platform. graphic for the NASA mobile...

2011-08-19

305

Molecular spectroscopy and planetary atmospheres  

Energy Technology Data Exchange (ETDEWEB)

With the improvements accomplished during the past 15 years in detection techniques and instrumentation and with the opening of space exploration, molecular spectroscopy has become a very efficient way to probe planetary atmospheres.

1984-01-01

306

Metronome to Coordinate the Breaths and Cardiac Compressions Delivered by Minimally-Trained Caregivers During Two-Person CPR  

Science.gov (United States)

Astronaut crew medical officers (CMO) aboard the International Space Station (ISS) receive 40 hours

2005-01-01

307

Long-term storage of solar heat  

Energy Technology Data Exchange (ETDEWEB)

Stochastic models for the simulation of global radiation are discussed. Thermal transients in the ground are analyzed. The performance of buried-pipe storage and a space heating system with long-term storage is described.

1981-06-01

308

Liquid Nitrogen Dewar Loading at KSC for STS-71 Flight  

Science.gov (United States)

Liquid nitrogen dewar loading at Kennedy Space Center for STS-71 flight with Stan Koszelak (right),

1995-01-01

309

LBA Calibrator Survey - NASA  

Science.gov (United States)

Group deal delay solution has fit 42 psec with 2.4% outliers. Group delay ambiguities with spacing 3.9 ns (another world record!) were successfully resolved. ...

310

Johnson News - NASA  

Science.gov (United States)

Nov 21, 2003... for the European Space Agency's Automated Transport Vehicle, a new, uncrewed station cargo vehicle targeted for launch late next year. ...

311

Impact of Ionospheric Scintillations on Space-Based ...  

Science.gov (United States)

... Zinn, J., Hoerlin, H., and Petschek, AG, "The Motion of Bomb Debris Follow- ing the Starfish Test," Radiation Trapped in the Earth's Magnetic Field ...

1991-06-01

312

INTERVIEW TRANSCRIPT - Johnson Space Center - NASA  

Science.gov (United States)

Nov 13, 2000 ... built to support the Milstar Program. That was pretty interesting, and I'll tell you, that was about the easiest job I ever had. ...

313

GLAST Project Status - NASA  

Science.gov (United States)

Space Network Ku-band service. ... Completed GLAST mission schedule and budget assessment .... Utilize Ku band SN link (TDRSS) for science data return ...

314

Fire Safety Concerns in Space Operations - NASA Technical Reports ...  

Science.gov (United States)

familiarity fire triangle (i.e., fuel, oxidant, and ignition source) are excluded. It Is obvious that for the baseline safety goal for spacecraft this ...

315

Feynman path integral representations for wave scattering by anisotropic perturbations  

Energy Technology Data Exchange (ETDEWEB)

We write a space-time Feynman Path Integral representation for scattered wave fields from a weakly/compact supported anisotropic non-homogeneity. (author)

2007-07-01

316

Fermion-boson symmetry through superluminal transformations  

Energy Technology Data Exchange (ETDEWEB)

We consider the Pauli theorem on the spin-statistics connection for faster-than-light particles. As the consequence of the unlocalizability of tachyons in space we conclude that their spin-statistics correlations are inverted.

1985-08-01

317

Far-out Pathways to Space: Great Guns? - ISTP  

Science.gov (United States)

The SHARP cannon. Hydrogen is compressed in the tube on top, the gun barrel is on bottom. When Jules Verne wrote in 1865 "From Earth to the Moon" he ...

318

Far-out Pathways to Space: Great Guns?  

Science.gov (United States)

Turbine Afterword The SHARP cannon. Hydrogen is compressed in the tube on top, the gun barrel is on bottom. When Jules Verne wrote in 1865 "From Earth to the Moon" he envisioned...

2011-09-03

319

Extended cognition and the space of social interaction  

British Library Electronic Table of Contents (United Kingdom)

The extended mind thesis (EM) asserts that some cognitive processes are (partially) composed of actions consisting of the manipulation and exploitation of environmental structures. Might some processes at the root of social cognition have a similarly extended structure? In this paper, I argue that social cognition is fundamentally an interactive form of space management-the negotiation and management of "we-space"-and that some of the expressive actions involved in the negotiation and management of we-space (gesture, touch, facial and whole-body expressions) drive basic processes of interpersonal understanding and thus do genuine social-cognitive work. Social interaction is a kind of extended social cognition, driven and at least partially constituted by environmental (non-neural) scaffold...

2011-01-01

320

Enhanced Aircraft Design Capability for the Automated ...  

Science.gov (United States)

... The third series used a correlated parameter covariance matrix derived from a generic database of modeling uncertainty for space structures [5-1 ...

1996-01-31

321

Effect of spacing and nitrogen fertilization on the establishment and biomass production of short rotation Poplar in Finland  

Energy Technology Data Exchange (ETDEWEB)

Short rotation trials using cuttings poplar (Populus x rasumowskyana) in Southern Finland investigated the establishment of poplar plantations and the effects of spacing and application of nitrogen fertilizer on biomass production over a period of 6 years. Thicker cuttings grew better whilst those of less than 1 cm diameter grew only moderately. Nitrogen fertilization improved height and diameter growth and above-ground dry mass yield. Woody biomass production was 4.2 dry tons/ha per year, at 300 kg/ha nitrogen. A spacing of 15 000 stems/ha gave the best yield after 4 years, but 5000 stems/ha was more productive spacing in the next 2 years. (author).

1989-01-01

322

EUROPEAN SPACE AGENCY Extension of the SOHO Mission  

Science.gov (United States)

closure of the BISON network, GOLF and VIRGO will remain the only instruments ...... Faraday Cup solar wind instrument as described in Ipavich et al (1998). ...

323

Dynamic Weapon-Target Assignment Problems with ...  

Science.gov (United States)

... defense's weapons are Space-based kinetic-kill vehicles ... I ti I obtained by dividing the weapons as ... of the optimal weapon-arge assigntments and ...

1988-06-01

324

Direct Detection Optical Intersatelllte Link at 220 Mbps Using ...  

Science.gov (United States)

on this technology has beenproposedas a payload on SpaceStation Freedom to be launched in the near future [1]. Direct detection 4-ary pulse position modula- ...

326

Defense Horizons. Number 18, October 2002. High-Energy ...  

Science.gov (United States)

... assets, particularly against ballistic missiles with weapons of mass ... more con- ventional missile and gun weapon systems. ... Similarly, space-based ...

2002-10-01

327

Deep Space Probe Science Experiment  

Science.gov (United States)

Briefly, 48 MOS microparticle sensors (essentially the same as those flown on .... at the Naval Research Lab to interpret the polarization of the incoming radio .... Adapter Satellite, to be published in Journal of Spacecraft and Rockets, 1994. ...

328

Dark star? - Johnson Space Center - NASA  

Science.gov (United States)

Jun 25, 1982 ... stove cooktop, great for camp or cot- ment for rent by day, week or month. $4, 000 neg. Call Mike, 483-4231 ...

329

DEFORESTATION - Earth from Space - Search Results  

Science.gov (United States)

Features: FOREST, DEFORESTATION, RIO JAMARI Geographic Region: BRAZIL .... Features: DEFORESTATION, TIERRAS BAJAS DEFORESTATION Geographic Region: BOLIVIA ...

330

D-branes in a big bang/big crunch universe: Misner space  

Energy Technology Data Exchange (ETDEWEB)

We study D-branes in a two-dimensional lorentzian orbifold R{sup 1,1}/{gamma} with a discrete boost {gamma}. This space is known as Misner or Milne space, and includes big crunch/big bang singularity. In this space, there are D0-branes in spiral orbits and D1-branes with or without flux on them. In particular, we observe imaginary parts of partition functions, and interpret them as the rates of open string pair creation for D0-branes and emission of winding closed strings for D1-branes. These phenomena occur due to the time-dependence of the background. Open string 2{yields}2 scattering amplitude on a D1-brane is also computed and found to be less singular than closed string case.

2005-09-01

331

Confidence-Based Performance Assessments for the BMDO ...  

Science.gov (United States)

... Notes Papers from the Proceedings AIAA 2nd Biennial ... Based (GB) Lower Tier Weapon System clearly ... are too short for space-based cueing to be ...

2001-03-27

332

Best Practices: Better Support of Weapon System Program ...  

Science.gov (United States)

... acquisition process has produced weapons that are ... F/A-22 Raptor, Space-Based Infrared System ... occur because DOD's weapon programs do ...

2005-11-01

333

Annual inside final - NASA  

Science.gov (United States)

The attendees this year included partic- ipants from space agencies, industry, and academia from Canada, the Czech Republic, France, Germany, Italy, Japan, ...

334

AeroSpace Information for a Changing World - NASA Technical ...  

Science.gov (United States)

Mar 1, 2011 ... Currently there is no compact, portable and real time neutron detector instrumentation available for use inside spacecraft or on planetary ...

335

AeroSpace Information for a Changing World - NASA Technical ...  

Science.gov (United States)

Mar 1, 2011 ... thermal behavior and structural changes of composite sandwich panels with a honeycomb core subjected to a variety of environmental effects. ...

336

A VIEW FROM FEW - Kennedy Space Center - Home - NASA  

Science.gov (United States)

credited for unused sick leave when they retire.) The FERS Sick Leave Credit would provide the exact same benefit to FERS ...

337

A Search for Core-Collapse Supernova Progenitors in Hubbk Space - NASA  

Science.gov (United States)

for massive star evolution, or they could all be very blue super- giant stars experiencing A , = 1-1.5 mag. The fact that the en- ...

338

A Methodology for Developing Timing Constraints for the ...  

Science.gov (United States)

... pursued for a similar space-based system, ... determine the most capable and opportunistic weapon ... Haim Baruch, Battle Management, AIAA, 2000, p ...

2003-12-01

339

7 1 Will Technology, Incorporated X - Marshall Space Flight Center ...  

Science.gov (United States)

reemployment, retirement (CSRS and FERS) severance pay, benefits, ... Advance Sick Leave Program, Military Leave, leave for blood donation, Sick Leave for ...

340

0100127 - Liquid nitrogen dewar for protein crystal growth - NASA  

Science.gov (United States)

Gaseous Nitrogen Dewar apparatus developed by Dr. Alex McPherson of the University of California, Irvine for use aboard Mir and the International Space ...

341

/l//IIl/ Kennedy Space Center, Florida 12899  

Science.gov (United States)

inhi bi Led ethylene glycol-water solutions for Apol lo spacecraft en- vironmental control systems (I), the concentration of sodium sulfi te ...

342

/g7?7"',d&k  

Science.gov (United States)

R. J. Schwinghamer: Magnetic Forming in Space,. Astronautics, September 1962, pp . 63-67. Burkhalter & White: New Tools for the Inquisitive ...

343

The PAMELA space mission  

Energy Technology Data Exchange (ETDEWEB)

The PAMELA (a Payload for Antimatter-Matter Exploration and Light-nuclei Astrophysics) space mission has been launched on-board the Resurs-DK1 satellite on June 15{sup th} 2006 from the Baikonur cosmodrome, in Kazakhstan. PAMELA is a particle spectrometer designed to study charged particles in the cosmic radiation with special focus on the investigation of the nature of dark matter, by mean of the measure of the cosmic-ray antiproton and positron spectra over the largest energy range ever achieved.

2009-03-15

344

Tachyons in compact spaces  

Energy Technology Data Exchange (ETDEWEB)

We discuss condensations of closed string tachyons localized in compact spaces. Time evolution of an on-shell condensation is naturally related to the worldsheet RG flow. Some explicit tachyonic compactifications of Type II string theory is considered, and some of them are shown to decay into supersymmetric theories known as the little string theories.

2005-05-01

345

Soviet military strategy in space  

Energy Technology Data Exchange (ETDEWEB)

This book examines the Soviet military space effort from its infancy in the 1950s to the spy craft and anti-satellite systems of today. It describes in detail the Soviet equivalents of the U.S. Star Wars program and explains technical and political issues in laymen's terms. A full text of major arms control agreements completes the volume.

1987-01-01

346

Simplified solar fraction estimation for space and water heating at dod installations. appendix c. water heating nomographs. Final report  

Energy Technology Data Exchange (ETDEWEB)

This report contains a set of nomographs which can be used to estimate the average annual solar fraction for solar space and water heating at a large number of DOD facilities. The solar fraction estimated from the nomograph is in close agreement with F-Chart 3.0 and allows for variation of the following parameters: annual load, collector area, collector transmittance-absorptance coefficient, and collector overall loss coefficient.

1982-09-01

347

Simplified solar fraction estimation for space and water heating at DOD installations. Final report  

Energy Technology Data Exchange (ETDEWEB)

A set of nomographs is provided which can be used to estimate the average annual solar fraction for solar space and water heating at a large number of DOD facilities. The solar fraction estimated from the nomograph is in close agreement with F-Chart 3.0 and allows for variation of the following parameters: annual load, collector area, collector transmittance-absorption coefficient, and collector overall loss coefficient.

1982-09-01

348

Regulation about the technical environment of buildings: boiler-rooms / ventilation systems; RETA: chaufferies / ventilation  

Energy Technology Data Exchange (ETDEWEB)

This CD-Rom edited by the French scientific and technical committee of the space heating, ventilation and air-conditioning industry (CoSTIC) presents a series of technical files about ventilation and space heating systems with several references to the current regulatory texts. Modifications of the original legislative texts have been integrated to the original texts for a more comfortable reading. Search is performed using diagrams and key-words. (J.S.)

2000-06-01

349

Realistic level density calculation for heavy nuclei  

Energy Technology Data Exchange (ETDEWEB)

A microscopic calculation of the level density is performed, based on a combinatorial evaluation using a realistic single-particle level scheme. This calculation relies on a fast Monte Carlo algorithm, allowing to consider heavy nuclei (i.e., large shell model spaces) which could not be treated previously in combinatorial approaches. An exhaustive comparison of the predicted neutron s-wave resonance spacings with experimental data for a wide range of nuclei is presented.

1994-12-31

350

Quantum tachyons in Schwarzschild space-time  

Energy Technology Data Exchange (ETDEWEB)

The wave equation of a spinless tachyon is studied in Schwarzschild space-time. In contrast to earlier approaches to the problem, it is shown that tachyonic static solutions satisfy a simple second-order linear differential equation regardless of the mass of the black hole and the mass parameter of the tachyon. Physical implication of the present approach is discussed. Using Langer modification of the WKB (Wentzel-Kramers-Brillouin) boundary condition an expression similar to the Bohr-Sommerfeld quantization condition is derived.

1981-02-01

351

Pseudostate description of breakup in the coupled-reaction-channel method: Numerical study of nonorthogonality effects  

Energy Technology Data Exchange (ETDEWEB)

To simulate the effects of the breakup channel on rearrangement amplitudes, the conventional coupled-reaction-channel (CRC) expansion is augmented by pseudoreaction channels. The construction of the projector for the extended CRC space is discussed, and transition-operator equations on this space are given. By solving the full and post-approximation forms of the CRC equations for a model three-particle problem, the crucial role played by the nonorthogonality terms is demonstrated.

1991-03-01

352

Pseudostate description of breakup in the coupled-reaction-channel method: Numerical study of nonorthogonality effects  

International Nuclear Information System (INIS)

To simulate the effects of the breakup channel on rearrangement amplitudes, the conventional coupled-reaction-channel (CRC) expansion is augmented by pseudoreaction channels. The construction of the projector for the extended CRC space is discussed, and transition-operator equations on this space are given. By solving the full and post-approximation forms of the CRC equations for a model three-particle problem, the crucial role played by the nonorthogonality terms is demonstrated.

353

Metastasis Detection in Sentinel Lymph Nodes: Comparison of a Limited Widely Spaced (NSABP protocol B-32) and a Comprehensive Narrowly Spaced Paraffin Block Sectioning Strategy  

UK PubMed Central (United Kingdom)

The NSABP B-32 trial is examining whether patients with initially negative sentinel lymph nodes (SLNs) who have occult metastases detected on deeper levels and cytokeratin immunohistochemistry...Full Text Available

2009-11-01

354

Laser weapons. II - Strategic laser weapons  

Science.gov (United States)

Potential strategic missions for laser weapons, particularly those involving space-based lasers, are discussed. The functions of space-based lasers and the history of their conceptual development are summarized, and the problems of implementing such systems, including the building of a suitable laser and power source, and resolving the problem of optics, are discussed. Ongoing development programs are described, and the contrasting views of the necessity and usefulness of strategic laser systems are set forth.

1982-07-01

355

Lagrange-Function Approach to Real-Space Order-N Electronic-Structure Calculations  

Energy Technology Data Exchange (ETDEWEB)

The Lagrange functions are a family of analytical, complete, and orthonormal basis sets that are suitable for efficient, accurate, real-space, order-N electronic-structure calculations. Convergence is controlled by a single monotonic parameter, the dimension of the basis set, and computational complexity is lower than that of conventional approaches. In this paper we review their construction and applications in linearscaling electronic-structure calculations.

2006-04-01

356

Gravitational fields with space-times of Binachi type IX  

International Nuclear Information System (INIS)

Spatially homogeneous space-times of Bianchi type IX are considered. A general scheme for the derivation of exact solutions of Einstein's equations corresponding to perfect fluid plus pure radiation fields is outlined. Some simple rotating Bianchi type IX cosmological models are presented. The details of these solutions are also discussed. 9 refs. (author).

357

Global existence for the Euler-Maxwell system  

CERN Document Server

The Euler-Maxwell system describes the evolution of a plasma when the collisions are important enough that each species is in a hydrodynamic equilibrium. In this paper we prove global existence of small solutions to this system set in the whole three-dimensional space, by combining the space-time resonance method, dispersive estimates, localization estimates and energy estimates. An important novelty is that we can prove a very slow growth of high derivatives even with a nonintegrable decay by reiterating the energy estimate.

2011-01-01

358

Fission fragment rockets: A new frontier  

Energy Technology Data Exchange (ETDEWEB)

A new reactor concept is described which would enable fission fragments to be continuously extracted from the reactor. Such a reactor has the potential of enabling extremely energetic and ambitious deep space missions. In this talk the basic physics issues involved in the operation of this type of reactor are outlined, and some possible applications to space exploration are described. 3 refs., 2 figs., 3 tabs.

1989-04-01

359

Fibre coupled dual-mode waveguide interferometer with $\\lambda $/130 fringe spacing  

CERN Document Server

Predictions and measurements of a multimode waveguide interferometer operating in a fibre coupled, ``dual-mode'' regime are reported. With a 1.32 micrometer source, a complete switching cycle of the output beam is produced by a 10.0 nanometer incremental change in the 8.0 micrometer width of the hollow planar mirror waveguide. This equates to a fringe spacing of $\\sim\\lambda /130$. This is an order of magnitude smaller than previously reported results for this form of interferometer.

2008-01-01

360

Experience with Aerosol Generation During Rotary Mode Core Sampling in the Hanford Single Shell Waste Tanks  

Energy Technology Data Exchange (ETDEWEB)

This document provides data on aerosol concentrations in tank head spaces, total mass of aerosols in the tank head space and mass of aerosols sent to the exhauster during Rotary Mode Core Sampling from November 1994 through June 1999. A decontamination factor for the RMCS exhauster filter housing is calculated based on operation data.

2000-01-24

361

Environmental interactions working group report  

Energy Technology Data Exchange (ETDEWEB)

Interactions between spacecraft systems and the space charged particle environment are reviewed and recommendations are presented for both near-term and far-term research considerations. Transient environment models, large space structures, solar and nuclear power systems/environment interactions, single event upsets, material degradation, and planetary missions are addressed.

1984-04-01

362

Covariant quantum equations in curved space-time, Lorentz covariance and tachyons  

International Nuclear Information System (INIS)

The author presents his views on the interrelation of quantum theory, space-time, Lorentz covariance and tachyons. He makes general observations on the nature of these topics and in particular on the nature of the mathematics used for their description and, without reaching any definite conclusions, points out some areas which require further critical examination. (W.D.L.).

363

Collective acceleration of electrons and ions in a high current relativistic electron beam. Final report  

International Nuclear Information System (INIS)

The original purpose of this research was an investigation into the use of slow space charge waves on weakly relativistic electron beams for ion acceleration. The work had three main objectives namely, the development of a suitable ion injector, the growth and study of the properties of slow space charge waves on an electron beam, and a combination of the two components parts into a suitable proof of principle demonstration of the wave accelerator. This work focusses on the first two of these objectives.

364

Attractors for nonlinear reaction-diffusion systems in unbounded domains via the method of short trajectories  

CERN Document Server

We consider a nonlinear reaction-diffusion equation settled on the whole euclidean space. We prove the well-posedness of the corresponding Cauchy problem in a general functional setting, namely, when the initial datum is uniformly locally bounded in L^2. Then we adapt the short trajectory method to establish the existence of the global attractor and, if the space dimension is at most 3, we also find an upper bound of its Kolmogorov's entropy.

2009-01-01

365

A_2 Toda theory in reduced WZNW framework and the representations of the W-algebra  

International Nuclear Information System (INIS)

Using the reduced WZNW formulation we analyse the classical W-orbit content of the space of classical solutions of the A_2 Toda theory. We define the quantized Toda field as a periodic primary field of the W-algebra satisfying the quantized equations of motion. We show that this local operator can be constructed consistently only in Hilbert space consisting of the representation corresponding to the minimal models of the W-algebra. (orig.).

1992-10-01

366

A submillimeter wavelength space-based imaging radar  

Science.gov (United States)

This report considers the use of a submillimeter wavelength space-based imaging radar. The main application envisioned is midcourse decoy discrimination for strategic defense, for which it would have the capability of producing a series of images, in real time, at strategic ranges, with less than meter scale resolution and with modest power requirements. Undoubtedly, there are other applications. The requirements for a SAR and ISAR imaging radar at submillimeter wavelength are determined, and the prospect for the development of RF sources to power the radar is examined.

1988-05-01

367

A multiply-connected space-time, black holes, and tachyons  

International Nuclear Information System (INIS)

The standard postulates of general relativity are modified by allowing changes of topologies in space-time, i.e. considering a multiply-connected manifold. This allows, for instance, a different description of black holes and, in particular, a more rigorous approach to previous work studying the connections between black holes and tachyons. (author).

368

A multigroup multiparticle formalism for multiplying systems Kolmogorov equations in the space-independent low-power model  

International Nuclear Information System (INIS)

The time-dependent probability distribution of neutrons, precursors and detectrons in a space-independent, low-power, multiplying assembly with a source is developed in the multigroup approximation as forward and backward Kolmogorov equations. The relationship between these as adjoint equations is made explicit in a tensor notation and the equations developed in the generating-function formalism. (author).

1982-01-01

369

Two-phase flow regime management for in-space power rejection management -- Feasibility study  

Energy Technology Data Exchange (ETDEWEB)

A novel two-phase flow management process useful for active thermal power rejection in space is introduced. The process serves as a condenser in a Rankine cycle and is applicable for thermal energy management needs in low gravity environments. Benefit is derived from the ability to utilize the high specific energy transport capability of two-phase flow, while not requiring mass-intensive solutions nor complex control strategies to maintain design energy balance integrity. Initial design calculations for a hypothetical space vapor cycle demonstration experiment were done and a steady-state computer model of the novel condensing process was created and used to evaluate its potential to maintain the design energy balance of the experiment. The experiment (approximately 28 kg) was a supercritical organic thermal loop operating between 500 and 400 Kelvin at a mass flow of 1 grain per second; using R-113 as the working fluid and rejecting all of its ...

1995-12-31

370

Two dimensional gyrokinetic turbulence  

CERN Document Server

Two dimensional gyrokinetics is a simple paradigm for the study of kinetic turbulence. We study the inertial range dual cascade, assuming a homogeneous and isotropic random forcing. This cascade occurs in phase-space (two dimensions in position-space plus one dimension in velocity-space) via the nonlinear phase-mixing process, at scales smaller than the Larmor radius. At these scales, we show that the turbulence is self-similar and exhibits power law spectra in position and velocity-space. The velocity-space spectrum is treated via a Hankel transform which fits naturally with the mathematical framework of gyrokinetics. We derive the exact relations for third order structure functions, in analogy to Kolmogorov's four-fifths law. For scales larger than the Larmor radius, the two dimensional gyrokinetic system may be reduced to the well-studied Charney--Hasegawa--Mima equation or the ...

2009-01-01

371

Towards an accurate model of the redshift space clustering of halos in the quasilinear regime  

CERN Document Server

Observations of redshift-space distortions in spectroscopic galaxy surveys offer an attractive method for measuring the build-up of cosmological structure, which depends both on the expansion rate of the Universe and our theory of gravity. Galaxies occupy dark matter halos, whose redshift space clustering has a complex dependence on bias that cannot be inferred from the behavior of matter. We identify two distinct corrections on quasilinear scales (~ 30-80 Mpc/h): the non-linear mapping between real and redshift space positions, and the non-linear suppression of power in the velocity divergence field. We model the first non-perturbatively using the scale-dependent Gaussian streaming model, which we show is accurate at the 10 (s>25) Mpc/h for the monopole (quadrupole) halo correlation functions. We use perturbation theory to predict the real space pairwise halo velocity statistics. Our fully analytic ...

2011-01-01

372

Stochastic Finsler D-particle Space-Time Foam Enhances Dark Matter Relics  

CERN Document Server

Within the context of space-time (D-particle) foam in string/brane-theory it is demonstrated that it is possible to generate non-extensive statistics. The D-particle foam model involves point-like brane defects (D-particles), which provide the topologically non-trivial foamy structures of space-time. The D-particles can capture and emit stringy matter and this leads to a recoil of D-particles. It is indicated how one effect of such a recoil of D-particles is a back reaction on the space-time metric of Finsler type which is stochastic. We show that such a type of stochastic space-time foam can lead to cosmological effects similar to those induced by modifications of particle distributions within the framework of Tsallis entropies. The restrictions placed on the free parameters of the Finsler type metric are obtained from solving the Boltzmann equation in this background for relic abundances of a Lightest ...

2010-01-01

373

Requirements for modeling and simulation of space RSTA assets  

Science.gov (United States)

The Department of Defense (DoD) has long depended on military support functions enabled by space reconnaissance, surveillance, and target acquisition (RSTA) assets. Future generation satellite capabilities will further push technologies in space - if the right technologies are deployed in the right numbers and with the right payloads. Modeling and simulation play major parts in developing and deploying such assets: 1) system and operational requirements determination, and 2) assessment of military utility of such assets. Each area is critical in a system"s life cycle. Requirements determination cuts across the issues of doctrine, organizations, training, materiel, leader development, personnel, and facilities (DOTMLPF). Military utility assessments are necessary to explore and quantify the military worth/benefit of space RSTA assets to operational commanders. Each of these areas requires relevant modeling/simulation tools ...

2004-09-01

374

High-efficiency GaAs solar cells  

Energy Technology Data Exchange (ETDEWEB)

An updated review of the state of the art in the development of GaAs solar cells is provided, with emphasis on AlGaAs-GaAs cells suitable for space applications. A set of theoretically derived characteristics is given for this type of solar cell. Comparison of measured performance with theory shows excellent agreement. Data on the effects of radiation damage (high-energy electrons, protons, and neutrons) is also integrated into a form useful for evaluation purposes. Techniques for fabricating (AlGa)As-GaAs solar cells in quantities large enough for practical applications are discussed and are shown to have been demonstrated. The possibility of extending these techniques to the fabrication of very thin low-weight cells for space applications is also considered. Finally, the results obtained to date in the development of GaAs solar cells for applications requiring concentrated sunlight are reviewed, for terrestrial as well as for ...

1984-05-01

375

Desorption of polycyclic aromatic hydrocarbons from carbon nanomaterials in water  

Energy Technology Data Exchange (ETDEWEB)

Desorption behavior of pyrene, phenanthrene and naphthalene from fullerene, single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs) was examined. Available adsorption space of carbon nanotubes (CNTs) was found to be the cylindrical external surface, neither the inner cavities nor inter-wall spaces due to impurities in the CNTs and restricted spaces (0.335 nm) of the MWCNTs, respectively. Desorption hysteresis was observed for fullerene but not for CNTs. Deformation-rearrangement was proposed to explain the hysteresis of polycyclic aromatic hydrocarbons (PAHs) for fullerene, due to the formation of closed interstitial spaces in spherical fullerene aggregates. However, long, cylindrical carbon nanotubes could not form such closed interstitial spaces in their aggregates due to their length, thus showing no significant hysteresis. High adsorption capacity and ...

2007-01-15

376

Asymptotic numbers and wave packets  

International Nuclear Information System (INIS)

An attempt is made to generalize the spaces of numbers and functions in order to consider certain problems in quantum mechanics, especially in the cases, where wave functions appear which do not belong to the Hilbert space L"2. Often the Soboljev - Schwartz distributions are used but they are not always the appropriate tool because they cannot be multiplied. A modification of the definition of generalized functions PSI(x vector) is proposed by particular conditions. Such conditions imposed on the wave function of a free particle seems to be the most natural by means of physics. It appears, however, that for all spaces with a real norm these conditions are contradictory. This implies together with the extension of the space of functions, an extension of the space of numbers with so called asymptotic numbers A. The four algebraic operations - addition, subtraction, multiplication and ...

1976-01-26

377

A design study of reactor core optimization for direct nuclear heat-to-electricity conversion in a space power reactor  

Energy Technology Data Exchange (ETDEWEB)

To propose a new design concept of a nuclear reactor used in the space, research has been conducted on the conceptual design of a new nuclear reactor on the basis of the following three main concepts: (1) Thermionic generation by thermionic fuel elements (TFE), (2) reactivity control by rotary reflector, and (3) reactor cooling by liquid metal. The outcomes of the research are: (1) A calculation algorithm was derived for obtaining convergent conditions by repeating nuclear characteristic calculation and thermal flow characteristic calculation for the space nuclear reactor. (2) Use of this algorithm and the parametric study established that a space nuclear reactor using 97% enriched uranium nitride as the fuel and lithium as the coolant and having a core with a radius of about 25 cm, a height of about 50 cm and a generation efficiency of about 7% can probably be operated continuously for at least more than ten years at 100 ...

1998-01-01

378

Recent Korean R&D in Satellite Communications  

Science.gov (United States)

The R&D in satellite communications in Korea has been driven mainly by KCC (Korea Communications Commission) but in a small scale compared to Korea space development program organized by MEST (Ministry of Education, Science and Technology). Public and civilian satcom sector R&D has been led mainly by ETRI with small/medium companies contrary to rare investment in private sector while military sector R&D has been orchestrated by ADD with defense industry. By the COMS (Communication, Ocean and Meteorological Satellite) experimental Ka-band payload, Korea pursues a space qualification of own technology for national infrastructure evolution as well as industrialization of space R&D results. Once COMS launched and space qualified in 2009, subsequent application experiments and new technology R&D like UHDTV will entail service and industry promotion. The payload technology is expected for ...

2009-01-01

379

Experimental investigation of mixed convection heat transfer from longitudinal fins in a horizontal rectangular channel: In natural convection dominated flow regimes  

Energy Technology Data Exchange (ETDEWEB)

Mixed convection heat transfer from longitudinal fins inside a horizontal channel has been investigated in the natural convection dominated region for a wide range of Rayleigh numbers and different fin heights and spacings. An experimental parametric study was made to investigate effects of fin spacing, fin height and magnitude of heat flux on mixed convection heat transfer from rectangular fin arrays heated from below in a horizontal channel. The optimum fin spacing to obtain maximum heat transfer has also been investigated. During the experiments constant heat flux boundary condition was realized and air was used as the working fluid. The velocity of fluid entering channel was kept nearly constant (0.02 {<=} w{sub in} {<=} 0.025 m/s) using a flow rate control valve so that Reynolds number was always about Re = 250. Experiments were conducted for modified Rayleigh numbers 3 x 10{sup 7} < Ra{sup *} ...

2009-10-15

380

Adaptation of the low-cost and low-power tactical split Stirling cryogenic cooler for aerospace applications  

Science.gov (United States)

Cryogenic coolers are often used in modern spacecraft in conjunction with sensitive electronics and sensors of military, commercial and scientific instrumentation. The typical space requirements are: power efficiency, low vibration export, proven reliability, ability to survive launch vibration/shock and long-term exposure to space radiation. A long-standing paradigm of exclusively using "space heritage" equipment has become the standard practice for delivering high reliability components. Unfortunately, this conservative "space heritage" practice can result in using outdated, oversized, overweight and overpriced cryogenic coolers and is becoming increasingly unacceptable for space agencies now operating within tough monetary and time constraints. The recent trend in developing mini and micro satellites for relatively inexpensive missions has prompted attempts to adapt leading-edge ...

2011-05-01

381

[The contribution of the Military Medical Academy to space exploration].  

Science.gov (United States)

The article examines the contribution of the Military Medical Academy as an educational, research and medical institutions in the establishment and development of the national Russian manned spaceflight. Lists the names of the Academy's scientists, working in laboratories and in the Cosmonaut Training Center. In 1958 the academy was formed Department of Aviation Medicine from the research laboratories of aviation medicine, psychophysiology, and encephalography, a division of pressure chambers and furnaces. Direct contribution to the preparation of the first manned space flight made by graduates of the academy, E.A. Karpov (the first chief of Cosmonauts Training Center. Yuri Gagarin) and I.A. Kolosov. Over the half century history of the Russian Space Military Medical Academy, prepared and sent to the CPC Gagarin more than 110 of its graduates. PMID:21770320

2011-04-01

382

Wave extrapolation in the spatial wavelet domain with application to poststack reverse-time migration  

Energy Technology Data Exchange (ETDEWEB)

A wavelet transformation is performed over each of the spatial coordinates of the scalar wave equation. This transformed equation is solved directly with a finite-difference scheme for both homogeneous and smooth inhomogeneous media. Wavefield extrapolation is performed completely in the spatial wavelet domain without transforming back into the space domain at each time step. The wavelet coefficients are extrapolated, rather than the wavefield itself. The numerical solution of the scalar wave equation in the spatial wavelet domain is closely related to the finite-difference method because of the compact support of the wavelet bases. Poststack reverse-time migration is implemented as an application. The resolution spaces of the wavelet transform provide a natural framework for multigrid analysis. Migrated images are constructed from various resolution spaces.

1998-03-01

383

The forward modeling and reverse time migration of seismic wave field in complex medium  

Energy Technology Data Exchange (ETDEWEB)

The space derivation term of a wave equation is accurately calculated using Fourier transform method, and the wave equation only relating to time derivative in time-space domain is derived. Solving this equation with the aid of central difference method brings the numerical recursion formula for forward modeling or reverse time migration of seismic wave field in the medium in which seismic velocity varies. The key to this method lies in introducing two auxiliary wave fields relating to velocity and spacial frequency of Fourier transform respectively after multi-dimensional Fourier transform respectively after multi-dimensional Fourier transform of space vector is made. Theoretically, this method is suitable to the forward modeling and migration of seismic wave field in complex area where seismic velocity and structure shape vary arbitrarily. Theoretical results proved this method satisfactory.

1988-01-01

384

Supergravity solutions without triholomorphic U(1) isometries  

International Nuclear Information System (INIS)

We investigate the construction of five-dimensional supergravity solutions that do not have any triholomorphic U(1) isometries. We construct a class of solutions that in various limits of parameters reduces to many of previously constructed five-dimensional supergravity solutions based on both hyper-Kaehler base spaces that can be put into a Gibbons-Hawking form and hyper-Kaehler base spaces that cannot be put into a Gibbons-Hawking form. We find a new solution which is over triaxial Bianchi type IX Einstein-hyper-Kaehler base space with no triholomorphic U(1) symmetry. One special case of this solution corresponds to a five-dimensional solution based on Eguchi-Hanson type II geometry.

2008-12-15

385

Subspace estimation and prediction methods for hidden Markov models  

CERN Document Server

Hidden Markov models (HMMs) are probabilistic functions of finite Markov chains, or, put in other words, state space models with finite state space. In this paper we examine subspace estimation methods for HMMs whose output lies a finite set as well. In particular we study the geometric structure arising from the non-minimality of the linear state space representation of HMMs, and consistency of a subspace algorithm arising from a certain factorisation of the singular value decomposition of the estimated linear prediction matrix. For this algorithm we show that the estimates of the transition and emission probability matrices are consistent up to a similarity transformation, and that the m-step linear predictor computed from the estimated system matrices is consistent, i.e. converges to the true optimal linear m-step predictor.

2009-01-01

386

Simulating the operation of photosensor-based lighting controls  

International Nuclear Information System (INIS)

Energy savings from the use of daylighting in commercial buildings are realized through implementation of photoelectric lighting controls that dim electric lights when sufficient daylight is available to provide adequate workplane illumination. The dimming level of electric lighting is based on the signal of a photosensor. Current simulation approaches for such systems are based on the questionable assumption that the signal of the photosensor is proportional to the task illuminance. This paper presents a method that simulates the performance of photosensor controls considering the acceptance angle, angular sensitivity, placement of the photosensor within a space, and color correction filter. The method is based on the multiplication of two fisheye images: one generated from the angular sensitivity of the photosensor and the other from a 180- or 360-degree fisheye image of the space as ''seen'' by the photosensor. The paper includes a detailed ...

387

Servicing a world elsewhere? Examining everyday work practices in the emerging economic spaces of Malaysia's business process outsourcing industry  

British Library Electronic Table of Contents (United Kingdom)

The paper seeks to illuminate everyday work practices in the economic spaces of Malaysia's business process outsourcing (BPO) industry. It draws upon empirical evidence from call centre staff and promotes analytical sensitivity to the experience of labour and spatiotemporal relations within the offshore back offices of multinational corporations located in Cyberjaya, Malaysia. The analysis provides an empirical snapshot of how IT-facilitated work practices in the global information economy are embedded and socially reproduced in everyday settings. To this end, the paper engages anthropologically with BPO labour, and critiques -globalist- representations of economic and social transformation frequently articulated through an abstract, dehumanized space of networks and flows often seen to wa...

2011-01-01

388

RECENT ACTIVITIES AT THE CENTER FOR SPACE NUCLEAR RESEARCH FOR DEVELOPING NUCLEAR THERMAL ROCKETS  

Energy Technology Data Exchange (ETDEWEB)

Nuclear power has been considered for space applications since the 1960s. Between 1955 and 1972 the US built and tested over twenty nuclear reactors/ rocket-engines in the Rover/NERVA programs. However, changes in environmental laws may make the redevelopment of the nuclear rocket more difficult. Recent advances in fuel fabrication and testing options indicate that a nuclear rocket with a fuel form significantly different from NERVA may be needed to ensure public support. The Center for Space Nuclear Research (CSNR) is pursuing development of tungsten based fuels for use in a NTR, for a surface power reactor, and to encapsulate radioisotope power sources. The CSNR Summer Fellows program has investigated the feasibility of several missions enabled by the NTR. The potential mission benefits of a nuclear rocket, historical achievements of the previous programs, and recent investigations into alternatives in design and materials for future systems ...

2001-09-01

389

Propagators and Matrix Basis on Noncommutative Minkowski Space  

CERN Document Server

We describe an analytic continuation of the Euclidean Grosse-Wulkenhaar and LSZ models which defines a one-parameter family of duality covariant noncommutative field theories interpolating between Euclidean and Minkowski space versions of these models, and provides an alternative regularization to the usual Feynman prescription. This regularization allows for a matrix model representation of the field theories in terms of a complex generalization of the usual basis of Landau wavefunctions. The corresponding propagators are calculated and identified with the Feynman propagators of the field theories. The regulated quantum field theories are shown to be UV/IR-duality covariant. We study the asymptotics of the regularized propagators in position and matrix space representations, and confirm that they generically possess a comparably good decay behaviour as in the Euclidean case.

2011-01-01

390

On the Nature of the Cosmological Constant Problem  

CERN Document Server

General relativity postulates the Minkowski space-time to be the standard flat geometry against which we compare all curved space-times and the gravitational ground state where particles, quantum fields and their vacuum states are primarily conceived. On the other hand, experimental evidences show that there exists a non-zero cosmological constant, which implies in a deSitter space-time, not compatible with the assumed Minkowski structure. Such inconsistency is shown to be a consequence of the lack of a application independent curvature standard in Riemann's geometry, leading eventually to the cosmological constant problem in general relativity. We show how the curvature standard in Riemann's geometry can be fixed by Nash's theorem on locally embedded Riemannian geometries, which imply in the existence of extra dimensions. The resulting gravitational theory is more general than general relativity, similar to brane-world ...

2009-01-01

391

Neural integrated control for a free-floating space robot with suddenly changing parameters  

British Library Electronic Table of Contents (United Kingdom)

Because the state of a free-floating space robot model is uncertain and sudden changes in the model parameters might undermine the stability of the system, this paper proposes a control strategy based on a variable structure neural integrated controller. This scheme does not need a precise space robot model, making use of the radial basis function neural network ability approach to learn about an uncertain model. The network weights are adjusted online in real-time. During the early period of the control phase and parameter changes, the variable structure controller compensates for the uncertain model which the neural network could not learn well. It also creates global asymptotic stability for the whole closed-loop system. Simulation results show that the controller can handle bad changea...

2011-01-01

392

Mirror symmetry for two-parameter models. Pt. 2  

Energy Technology Data Exchange (ETDEWEB)

We describe in detail the space of the two Kaehler parameters of the Calabi-Yau manifold P[sub 4][sup (1,1,1,6,9)][D. R. Morrison, 1993] by exploiting mirror symmetry. The large complex structure limit of the mirror, which corresponds to the classical large radius limit, is found by studying the monodromy of the periods about the discriminant locus, the boundary of the moduli space corresponding to singular Calabi-Yau manifolds. A symplectic basis of periods is found and the action of the Sp(6, Z) generators of the modular group is determined. From the mirror map we compute the instanton expansion of the Yukawa couplings and the generalized N=2 index, arriving at the numbers of instantons of genus zero and genus one of each bidegree. We find that these numbers can be negative, even in genus zero. We also investigate an SL(2, Z) symmetry that acts on a boundary of the moduli space. ((orig.))

1994-11-07

393

Mirror symmetry for two-parameter models. Pt. 2  

International Nuclear Information System (INIS)

We describe in detail the space of the two Kaehler parameters of the Calabi-Yau manifold P_4"("1","1","1","6","9")[D. R. Morrison, 1993] by exploiting mirror symmetry. The large complex structure limit of the mirror, which corresponds to the classical large radius limit, is found by studying the monodromy of the periods about the discriminant locus, the boundary of the moduli space corresponding to singular Calabi-Yau manifolds. A symplectic basis of periods is found and the action of the Sp(6, Z) generators of the modular group is determined. From the mirror map we compute the instanton expansion of the Yukawa couplings and the generalized N=2 index, arriving at the numbers of instantons of genus zero and genus one of each bidegree. We find that these numbers can be negative, even in genus zero. We also investigate an SL(2, Z) symmetry that acts on a boundary of the moduli space. ((orig.)).

394

Miguel Sanchez Pena (1925-2009) organizer of the space activities in Argentina  

British Library Electronic Table of Contents (United Kingdom)

One of the most important and active pioneers of the space activities in Argentina was Miguel Sanchez Pena, an aeronautical engineer and an officer of the Argentine Air Force. Sanchez Pena was the organizer of Argentina's governmental space program in the 1970s and part of the 80s, and contributed immeasurably to the Nation's sounding rocket program. Born in Mendoza, Argentina in 1925, Sanchez Pena attended the Military Aviation School (Escuela de Aviacion Militar) in Cordoba, and later the Air Force Engineering School. Graduated as an engineer in 1959 he was sent to the University of Michigan in the United States to complete his graduate studies earning a Masters of Science degree in Aerospace Engineering. There he had the opportunity to study with several future NASA astronauts such as T...

2011-01-01

395

Microstructural changes of stearic acid films by immersion in salt solution  

Energy Technology Data Exchange (ETDEWEB)

X-Ray reflectivity has been used to investigate the microstructural changes of solution-cast stearic acid films before and after immersion in CoCl{sub 2} solutions. Before immersion, the films possess a well-defined layered structure with an interlayer spacing of 4.01{+-}0.05 nm. After the films were immersed in the CoCl{sub 2} solutions, a new set of equidistant diffraction peaks emerge, the corresponding interlayer spacing of which is 5.13{+-}0.05 nm. The X-ray photoelectron spectra of the films indicate the existence of cobalt ions inside the films after immersion. It is concluded that the permeation of the cobalt ions into the hydrophilic interlayer causes the stearic acid molecules to reorient perpendicular to the films, resulting in the increase of interlayer spacing and the roughening of the interfaces.

2003-11-01

396

Linear family of Lie brackets on the space of matrices $Mat(n\\times m,\\K)$ and Ado's Theorem  

CERN Document Server

In this paper we classify a linear family of Lie brackets on the space of rectangular matrices $Mat(n\\times m,\\K)$ and we give an analogue of the Ado's Theorem. We give also a similar classification on the algebra of the square matrices $Mat(n, \\K)$ and as a consequence, we prove that we can't built a faithful representation of the $(2n+1)$-dimensional Heisenberg Lie algebra $\\mathfrak{H}_n$ in a vector space $V$ with $\\dim V\\leq n+1$. Finally, we prove that in the case of the algebra of square matrices $Mat(n,\\K)$, the corresponding Lie algebras structures are a contraction of the canonical Lie algebra $\\mathfrak{gl}(n,\\K)$.

2008-01-01

397

Jet plume injection and combustion system for internal combustion engines  

Energy Technology Data Exchange (ETDEWEB)

This invention is comprised of an improved combustion system for an internal combustion engine is disclosed wherein a rich air/fuel mixture is furnished at high pressure to one or more jet plume generator cavities adjacent to a cylinder and then injected through one or more orifices from the cavities into the head space of the cylinder to form one or more turbulent jet plumes in the head space of the cylinder prior to ignition of the rich air/fuel mixture in the cavity of the jet plume generator. The portion of the rich air/fuel mixture remaining in the cavity of the generator is then ignited to provide a secondary jet, comprising incomplete combustion products which are injected into the cylinder to initiate combustion in the already formed turbulent jet plume. Formation of the turbulent jet plume in the head space of the cylinder prior to ignition has been found to yield a higher maximum combustion pressure in the ...

1992-12-31

398

Geometric group theory and arithmetic diameter  

CERN Document Server

Let X be a group with identity e, let A be an infinite set of generators for X, and let (X,d_A) be the metric space with the word metric d_A induced by A. It is proved that if the diameter of the space is infinite, then for every positive integer h there are infinitely many elements x in X with d_A(e,x)=h. It is proved that if P is a nonempty finite set of prime numbers and A is the set of positive integers whose prime factors all belong to P, then the diameter of the metric space (\\Z,d_A) is infinite. Let \\lambda_A(h) denote the smallest positive integer x with d_A(e,x)=h. It is an open problem to compute \\lambda_A(h) and estimate its growth rate.

2011-01-01

399

GRI's Gas Appliance Technology Center Activities at Battelle. Final report, 1986-1992  

Science.gov (United States)

The Gas Research Institute established the Gas Appliance Technology Center (GATC) in 1982 to develop improved gas appliances. Between 1986 and 1992, the scope of GATC activities at Battelle included technology transfer and overall industry support, residential appliances, commercial appliances, and residential space conditioning. The following tasks are representative of the GATC activities described in the report; gas burner technology, appliance venting, emissions, water heating, range/oven technology, self-powered appliances, commercial cooktop burners, reconstituting ovens, appliance reliability improvement, combination space-heating/water-heating systems, condensing heat exchangers, corrosion testing, and space heating technology. The report includes references to available sources for further reading.

1993-08-01

400

Fourier duality as a quantization principle  

Energy Technology Data Exchange (ETDEWEB)

The Weyl-Wigner prescription for quantization on Euclidean phase spaces makes essential use of Fourier duality. The extension of this property to more general phase spaces requires the use of Kac algebras, which provide the necessary background for the implementation of Fourier duality on general locally groups. Kac algebras - and the duality they incorporate are consequently examined as candidates for a general quantization framework extending the usual formalism. Using as a test case the simplest non-trivial phase space, the half-plane, it is shown how the structures present in the complete-plane case must be modified. Traces, for example, must be replaced by their noncommutative generalizations - weights - and the correspondence embodied in the Weyl-Wigner formalism is no more complete. Provided the underlying algebraic structure is suitably adapted to each case, Fourier duality is shown to be indeed a very powerful ...

1996-08-01

401

Experimental investigation of mixed convection heat transfer from longitudinal fins in a horizontal rectangular channel  

British Library Electronic Table of Contents (United Kingdom)

Mixed convection heat transfer from longitudinal fins inside a horizontal channel has been investigated for a wide range of modified Rayleigh numbers and different fin heights and spacings. An experimental parametric study was made to investigate effects of fin spacing, fin height and magnitude of heat flux on mixed convection heat transfer from rectangular fin arrays heated from below in a horizontal channel. The optimum fin spacing to obtain maximum heat transfer has also been investigated. During the experiments constant heat flux boundary condition was realized and air was used as the working fluid. The velocity of fluid entering channel was kept nearly constant (0.15win0.16m/s) using a flow rate control valve so that Reynolds number was always about Re=1500. Experiments were conducted...

2010-01-01

402

Effects of size and spacing of uniformly distributed pearlite particles on fatigue crack growth behavior of ferrite pearlite steels  

British Library Electronic Table of Contents (United Kingdom)

Fatigue crack growth tests of three ferrite-pearlite steels with different size and spacing of pearlite particles, which were uniformly distributed in the ferrite matrix, were carried out to investigate the effect of microstructure on fatigue crack growth behavior in the Paris regime. The fatigue crack growth rates for the three materials did not coincide with each other, even when the crack growth curves were arranged by the effective stress intensity factor range. From in situ observations, crack tip stress shielding phenomena, such as interlocking and branching, were found on the crack wake, which enhanced fatigue crack growth resistance. A small size and spacing of pearlite particle seemed to induce small but frequent crack deflections, which resulted in crack closure phenomena. On the...

2010-01-01

403

Decoherence, entanglement decay, and equilibration produced by chaotic environments  

CERN Document Server

We investigate decoherence in quantum systems coupled via dephasing-type interactions to an arbitrary environment with chaotic underlying classical dynamics. The coherences of the reduced state of the central system written in the preferential energy eigenbasis are quantum Loschmidt echoes, which in the strong coupling regime are characterized at long times scales by fluctuations around a constant mean value. We show that due to the chaotic dynamics of the environment, the mean value and the width of the Loschmidt echo fluctuations are inversely proportional to the quantity we define as the effective Hilbert space dimension of the environment, which in general is smaller than the dimension of the entire available Hilbert space. Nevertheless, in the semiclassical regime this effective Hilbert space dimension is in general large, in which case even a chaotic environment with few degrees of freedom produces decoherence without ...

2011-01-01

404

Conjugate variables in quantum field theory: the basic case  

CERN Document Server

Within standard quantum field theory of one scalar field we define operators conjugate to the energy-momentum operators of the theory. They are singled out by calculational simplicity in Fock space. In terms of the underlying scalar field they are non-local. We establish their algebra where it turns out that time and space operators do not commute. Their transformation properties with respect to the conformal group are derived. Solving their eigenvalue problem permits to reconstruct the Fock space in terms of the eigenstates. It is indicated how Paulis theorem may be circumvented. As an application we form the analogue of S-matrices which yields information on the structure of the underlying spacetime. Similarly we define fields and look at their equations of motion.

2010-01-01

405

Complex plasma: dusts in plasma  

International Nuclear Information System (INIS)

Dust particles in a plasma are charged negatively and are subject to various types of forces, including a drag force by plasma particles and a force due to the collective nature of a plasma. Dust particles are found in a sheath in laboratories balanced by the gravitational force and the electric force, while dust particles in space are ubiquitous, including planetary magnetospheres and interstellar space. Because of the novel nature of a complex system involving plasma particles and dust particles in a collective way, the dusty plasma is often called a complex plasma. The complex plasma is characterized by two distinctly different scales in time and in space. The plasma with electrons, ions and neutrals is characterized by the collective motion with a fast time scale and a short wavelength, while the dust particles move in a slow time scale and a long spatial scale. Some fundamental aspects of a complex plasma are reviewed ...

2007-04-21

406

Asymptotics and Hamiltonians in a First order formalism  

CERN Document Server

We consider 4-dimensional space-times which are asymptotically flat at spatial infinity and show that, in the first order framework, action principle is well-defined \\emph{without the need of infinite counter terms.} It naturally leads to a covariant phase space in which the Hamiltonians generating asymptotic symmetries provide the total energy-momentum and angular momentum of the space-time. We address the subtle but important problems that arise because of logarithmic translations and super-translations both in the Langrangian and Hamiltonian frameworks. As a forthcoming paper will show, the treatment of higher dimensions is considerably simpler. Our first order framework also suggests a new direction for generalizing the spectral action of non-commutative geometry.

2008-01-01

407

The all-electric drill ship  

Energy Technology Data Exchange (ETDEWEB)

Oil, in various forms, has been used for thousands of years and has even been recommended as a medicinal product. Starting in the mid-19. century, however, mineral oil production became an economic, political, social and scientific gold mine. Subterranean and offshore drilling rigs have created colossal fortunes among multinationals and made certain nations extremely wealthy. Starting in the 1920's, oil companies began to explore the possibilities of undersea drilling, but it was only in 1947 that the first offshore drilling rig was set up. With three-quarters of the planet covered by water, it was inevitable that oil companies would turn to offshore drilling - especially as sub-sea oil fields may cover as much as 84 million square kilometres. Drilling rigs now go deeper than ever and are able to operate in up to 3000 meters water depth. This paper will present the technical merits of two similar all-electric drill-ships 'Pride Africa' and 'Pride ...

2000-07-01

408

Patterns of lineage diversification in the genus Naso (Acanthuridae).  

Science.gov (United States)

The evolutionary history of the reef fish genus Naso (F. Acanthuridae) was examined using a complete species-level molecular phylogeny of all recognized (19) species based on three loci (one nuclear ETS2 and two mitochondrial 16S, cyt b). This study demonstrates that distinct foraging modes and specialized body shapes arose independently at different times in the evolutionary history of the genus. Members of the subgenus Axinurus, characterized by a scombriform morphology, caudal fin structure and pelagic foraging mode, were consistently placed basal to the remaining Naso species, suggesting that pelagic foraging is plesiomorphic and benthic foraging derived in this genus. We used a genus-level phylogeny (nuclear marker, ETS2), which included several taxa from all other acanthurid genera, to obtain a range of age estimates for the most recent common ancestor of the genus Naso. These age estimates (range of 52-43.3 MY) were then used to estimate divergence times (by nonparametric rate ...

2004-07-01

409

Oxygen plasma treatment and deposition of CN_x on a fluorinated polymer matrix composite for improved erosion resistance  

International Nuclear Information System (INIS)

The use of polymer matrix composites in aerospace propulsion applications is currently limited by insufficient resistance to erosion by abrasive media. Erosion resistant coatings may provide necessary protection; however, adhesion to many high temperature polymer matrix composite (PMC) materials is poor. A low pressure oxygen plasma treatment process was developed to improve adhesion of CN_x coatings to a carbon reinforced, fluorinated polymer matrix composite. Fullerene-like CN_x was selected as an erosion resistant coating for its high hardness-to-elastic modulus ratio and elastic resilience which were expected to reduce erosion from media incident at different angles (normal or glancing) relative to the surface. In situ x-ray photoelectron spectroscopy was used to evaluate the effect of the plasma treatment on surface chemistry, and electron microscopy was used to identify changes in the surface morphology of the PMC substrate after plasma exposure. The fluorine ...

2007-07-01

410

Overview of electrochemical power sources for electric and hybrid-electric vehicles.  

Energy Technology Data Exchange (ETDEWEB)

Electric and hybrid-electric vehicles are being developed and commercialized around the world at a rate never before seen. These efforts are driven by the prospect of vehicles with lower emissions and higher fuel efficiencies. The widespread adaptation of such vehicles promises a cleaner environment and a reduction in the rate of accumulation of greenhouse gases, Critical to the success of this technology is the use of electrochemical power sources such as batteries and fuel cells, which can convert chemical energy to electrical energy more efficiently and quietly than internal combustion engines. This overview will concentrate on the work being conducted in the US to develop advanced propulsion systems for the electric and hybrid vehicles, This work is spearheaded by the US Advanced Battery Consortium (USABC) for electric vehicles and the Partnership for a New Generation of Vehicle (PNGV) for hybrid-electric vehicles, both of which can be read about on the world ...

1999-02-12

411

Multiphase integral reacting flow computer code (ICOMFLO): User`s guide  

Energy Technology Data Exchange (ETDEWEB)

A copyrighted computational fluid dynamics computer code, ICOMFLO, has been developed for the simulation of multiphase reacting flows. The code solves conservation equations for gaseous species and droplets (or solid particles) of various sizes. General conservation laws, expressed by elliptic type partial differential equations, are used in conjunction with rate equations governing the mass, momentum, enthalpy, species, turbulent kinetic energy, and turbulent dissipation. Associated phenomenological submodels of the code include integral combustion, two parameter turbulence, particle evaporation, and interfacial submodels. A newly developed integral combustion submodel replacing an Arrhenius type differential reaction submodel has been implemented to improve numerical convergence and enhance numerical stability. A two parameter turbulence submodel is modified for both gas and solid phases. An evaporation submodel treats not only droplet evaporation but size dispersion. Interfacial ...

1997-11-01

412

Liuhua 11-1 development -- Design and fabrication considerations for the FPSO Nanhai Sheng Li  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the development, design, and fabrication of the crude oil process facilities, and the conversion of an existing tanker for use at the Liuhua 11-1 Field. Over a 16-month period spanning 1994 and 1995, Amoco Orient Petroleum Company, and partners, China Offshore Oil Nanhai East Corporation (CONHE), and Kerr-McGee China Petroleum Ltd., converted a crude oil tanker originally built in 1975 to the Nanhai Sheng Li, the floating production, storage and offloading (FPSO) facility for the Liuhua 11-1 Field. The FPSO will process up to 65,000 BOPD produced from 20 subsea wells located 1.7 miles away. In addition to the processing facilities for produced oil and water, the FPSO has a processed crude oil storage capacity of 715,000 bbls. The ship`s propulsion system was removed during the conversion, because the FPSO is permanently moored at site by means of a 10-point, ``soft`` mooring. The mooring system was designed to survive the 100-year-return-period ...

1996-12-31

413

Lightweight electric-powered vehicles. Which financial incentives after the large-scale field tests at Mendrisio?  

International Nuclear Information System (INIS)

How should lightweight electric-powered vehicles be promoted, after the large-scale fleet test being conducted at Mendrisio (southern Switzerland) is completed in 2001, and are there reasons to put question marks behind the current approach? The demand for electric vehicles, and particularly the one in the automobile category, has remained at a persistently low level. As it proved, any appreciable improvement of this situation is almost impossible, even with substantial financial incentives. However, the unsatisfactory sales figures have little to do with the nature of the fleet test itself or with the specific conditions at Mendrisio. The problem is rather of structural nature. For (battery-operated) electric cars the main problem at present is the lack of an expanding market which could become self-supporting with only a few additional incentives. Various strategies have been evaluated. Two alternatives were considered in particular: a strategy to promote explicitly electric vehicles ...

414

Environmental, health, and safety issues of sodium-sulfur batteries for electric and hybrid vehicles. Volume 1, Cell and battery safety  

Energy Technology Data Exchange (ETDEWEB)

This report is the first of four volumes that identify and assess the environmental, health, and safety issues involved in using sodium-sulfur (Na/S) battery technology as the energy source in electric and hybrid vehicles that may affect the commercialization of Na/S batteries. This and the other reports on recycling, shipping, and vehicle safety are intended to help the Electric and Hybrid Propulsion Division of the Office of Transportation Technologies in the US Department of Energy (DOE/EHP) determine the direction of its research, development, and demonstration (RD&D) program for Na/S battery technology. The reports review the status of Na/S battery RD&D and identify potential hazards and risks that may require additional research or that may affect the design and use of Na/S batteries. This volume covers cell design and engineering as the basis of safety for Na/S batteries and describes and assesses the potential chemical, electrical, and thermal ...

1992-09-01

415

Environmental, health, and safety issues of sodium-sulfur batteries for electric and hybrid vehicles  

Energy Technology Data Exchange (ETDEWEB)

This report is the first of four volumes that identify and assess the environmental, health, and safety issues involved in using sodium-sulfur (Na/S) battery technology as the energy source in electric and hybrid vehicles that may affect the commercialization of Na/S batteries. This and the other reports on recycling, shipping, and vehicle safety are intended to help the Electric and Hybrid Propulsion Division of the Office of Transportation Technologies in the US Department of Energy (DOE/EHP) determine the direction of its research, development, and demonstration (RD D) program for Na/S battery technology. The reports review the status of Na/S battery RD D and identify potential hazards and risks that may require additional research or that may affect the design and use of Na/S batteries. This volume covers cell design and engineering as the basis of safety for Na/S batteries and describes and assesses the potential chemical, electrical, and thermal hazards and ...

1992-09-01

416

hysics Facility - NASA  

Science.gov (United States)

vehicles including the H2-A rocket and the space shuttle. .... The vacuum can's main function is to provide a high vacuum so that the science experiment and its sensors ... EMI-shielded power conversion from the incoming ISS power supply. 4. ...

417

Volume 2- Technical Approach - IMAGE Science Center - NASA  

Science.gov (United States)

Power system analysis shows the output from the solar arrays varies as a function .... Each array corresponds to a raw image browse product, which is generated by .... low outgassing, ability to withstand long-term exposure to the space ...

418

Variable domain I of nematode CLEs directs post-translational targeting of CLE peptides to the extracellular space  

UK PubMed Central (United Kingdom)

Effector proteins expressed in the esophageal gland cells of cyst nematodes are delivered into plant cells through a hollow, protrusible stylet. Although evidence indicates that effector proteins function...Full Text Available

2010-12-01

419

Time Travel Through A Trail Of ... - Near-Earth Object Program - NASA  

Science.gov (United States)

Dolores Beasley Headquarters, Washington, DC July 19, 2000 (Phone: 202/358- 1753) Bill Steigerwald Goddard Space Flight Center, Greenbelt, MD (Phone: ...

420

Thermal energy considerations on solar cavity wall building  

Energy Technology Data Exchange (ETDEWEB)

The dwelling is equipped with solar collectors which heat the air circulating in the cavity walls and the space beneath the floors. The thermal aspects of such a building are described. Heat balance, losses, heating by the sun in different seasons are described. Different measures taken to reduce the energy losses are described.

1983-02-01

421

The role of Computerized Tomography in osteoid-osteoma diagnosis  

International Nuclear Information System (INIS)

Alcaptonuria is a rare autosomal recessive metabolic disease, due to the lack of homogentisic acid oxidase. The following accumulation of homogentisic acid brings about a black discoloration of both the urine alcaptonuria) and connective tissue (ochronosis). The ochronotic alterations into joint cartilages cause degenerative arthropathy and osteopenia. The radiological features of three unrelated cases of alcaptonuria are reported. Radiographic abnormalities of ochconotic arthropathy are found in both the spine and the extraspinal joints. In the spine, the progressive calcification and ''vacuum'' phenomenon of disc spaces are the most characteristic findings. Disc space narrowing is associated with calcification and marginal sclerosis of vertebral bodies and is accentuated by osteopenia. Osteophytes are usually absent or of small size; neverthless progressive formation of marginal intervertebral bridges and obliteration of disc ...

1988-01-01

422

The relationship of time and space  

CERN Document Server

We show that, in addition to radiation travelling at the speed of light, QED theory predicts a second type of radiation with an infinite velocity. We also show that charge, as it appears in the Dirac equation, may have a triune nature.

2004-01-01

423

The Harris M. Schurmeier Collection, 1970-1986 3.0 cubic ... - NASA  

Science.gov (United States)

SDI was a space-based defense system designed to ... satellites that could detect a massive nuclear launch within seconds, orbiting laser weapons to destroy the ..... AIAA Washington Conference, memorandum from T. W. Hamilton to H. ...

424

Sunny days! - Johnson Space Center - NASA  

Science.gov (United States)

May 18, 2001 ... Jeff Ashby, a Navy captain and veteran of ..... with the Department of Defense to acquire enough ..... Protection Handbook (Chapter 404). Each ..... x35416 or go to the website: http://www.ghg.net/cbr/jscas/ ...

425

State-Space Modeling Indicates Rapid Invasion of an Alien Shrub in Coastal Dunes  

Science.gov (United States)

... uncertainty. The method is applied for the invasive shrub Rosa rugosa (Japanese rose) in Danish fixed dunes. The probability ... habitat code 2130). In 14 sites, the invasive shrub Rosa rugosa was recorde...

426

Sparganosis in the Lumbar Spine : Report of Two Cases and Review of the Literature  

UK PubMed Central (United Kingdom)

Sparganosis is a rare parasitic infection affecting various organs, including the central nervous system, especially the lumbar epidural space. This report describes the identification of disease and...Full Text Available

2011-04-01

427

Space-Frame Connection for Small-Diameter Round Timber.  

Science.gov (United States)

To promote more efficient use of small-diameter timber, research efforts are being focused on the development and evaluation of connection methods that can be easily applied to non-standard round wood profiles. This report summarizes an evaluation of a 'd...

2005-01-01

428

Space and the parietal cortex  

UK PubMed Central (United Kingdom)

Current views of the parietal cortex have difficulty accommodating the human inferior parietal lobe (IPL) within a simple dorsal versus ventral stream dichotomy. In humans, lesions of the right IPL...Full Text Available

2007-01-01

429

Sp(2)-BRST  

Energy Technology Data Exchange (ETDEWEB)

A general method is given for the construction of gauge-fixed actions for theories with local gauge symmetries. The method is based on the single requirement that the space of fields carries an irreducible representation of the Sp(2)-BRST algebra, with respect to which the resultant actions are then automatically invariant.

1988-09-01

430

Signal and imaging sciences workshop proceedings  

Energy Technology Data Exchange (ETDEWEB)

Papers are presented in the areas of: Medical Technologies; Non-Destructive Evaluation; Applications of Signal/Image Processing; Laser Guide Star and Adaptive Optics; Computational Electromagnetic, Acoustics and Optics; Micro-Impulse Radar Processing; Optical Applications; TANGO Space Shuttle.

1997-11-01

431

Shuttle managers - Johnson Space Center - NASA  

Science.gov (United States)

Sep 28, 1990 ... RCA Whirlpool builtins, gas stove and cooktop,. 998-7872. Shelly,383-7153. '77 Ford Pinto. runs, needs some work. faded red, ...

432

Sex and space destabilize intransitive competition within and between species  

UK PubMed Central (United Kingdom)

Organisms ranging from bacteria and corals to plants and vertebrates can form intransitive competitive networks, in which coexistence can be maintained because no one species or genotype is superior...Full Text Available

2008-08-22

433

Serving the Marshall Space Flight Center - The Marshall Star - NASA  

Science.gov (United States)

Oct 20, 2005 ... GE over-the-counter microwave, $40; Kitchen-Aid cooktop,. $75; both almond colored. 883-2877. Mossberg 835, RT Camo, slug barrel, scope. ...

434

Sequence space coverage, entropy of genomes and the potential to detect non-human DNA in human samples  

UK PubMed Central (United Kingdom)

BackgroundGenomes store information for building and maintaining organisms. Complete sequencing of many genomes provides the opportunity to study and compare global information properties...Full Text Available

435

Satellite imagery in the study and forecast of malaria  

UK PubMed Central (United Kingdom)

More than 30 years ago, human beings looked back from the Moon to see the magnificent spectacle of Earth-rise. The technology that put us into space has since been used to assess the damage...Full Text Available

2002-02-07

436

SG Report on Harmony with Nature final single-spaced.doc  

Wastenet

of early humanitarians, and the vivisectors turned to Rene Descartes (1596 1650 ) to justify ...A celebrated mathematician, physiologist, and psychologist, Descartes provided a general philosophy of the irrelevance of ethics to the ...Animals, according to Descartes, were insensible and irrational machines; moved, like clocks, but

437

Rolling tachyons in string cosmology  

Energy Technology Data Exchange (ETDEWEB)

We study the role of rolling tachyons in the cosmological model with dilatonic gravity. In the string frame, flat space solutions of both initial-stage and late-time are obtained in closed form. In the Einstein frame, we show that every expanding solution is decelerating.

2003-01-23

438

Resolution enhancement by subtraction of confocal signals taken at different pinhole sizes.  

Science.gov (United States)

Subtractive imaging in confocal fluorescence light microscopy is based on the subtraction of a suitably weighted widefield image from a confocal image. An approximation to a widefield image can be obtained by detection with an opened confocal pinhole. The subtraction of images enhances the resolution in-plane as well as along the optic axis. Due to the linearity of the approach, the effect of subtractive imaging in Fourier-space corresponds to a reduction of low spatial frequency contributions leading to a relative enhancement of the high frequencies. Along the direction of the optic axis this also results in an improved sectioning. Image processing can achieve a similar effect. However, a 3D volume dataset must be acquired and processed, yielding a result essentially identical to subtractive imaging but superior in signal-to-noise ratio. The latter can be increased further with the technique of weighted averaging in Fourier-space. A comparison ...

2003-01-01

439

Relativistic Feynman-type integrals  

Energy Technology Data Exchange (ETDEWEB)

It is shown that within the framework of the Kershaw stochastic model generalized by the author to the relativistic case a Feynman-type process may be constructed which can formally be understood as a diffusion phenomenon in Euclidean space. This makes it possible to introduce a real probability measure in the scheme of quantum mechanics proposed by Feynman.

1980-05-01

440

Priroda module docks with Mir station today - Johnson Space Center ...  

Science.gov (United States)

Apr 26, 1996 ... StainlesssteelJenn-Air cooktop w/4 burners, $20. Sam,332-3168. Sale:Condo, Friendswood,3-2-2A,1411sq It,. 409-925-4862. ...

441

Print - NASA  

Science.gov (United States)

Jul 17, 2008 ... The first version uses a red-green-blue filter; the second, an infrared-green- blue. Videos credit: Donald J. Lindler, Sigma Space Corporation/GSFC; ... The video will help us connect a varying point of planetary light ...

442

Position-sensitive proportional counter for space-based X-ray imaging studies  

International Nuclear Information System (INIS)

ASTROSAT, India's first dedicated astronomy satellite is slated for launch in 2007. The primary science objective of ASTROSAT is to explore the Universe using broad-band instruments covering optical, UV, soft X-ray and hard X-ray studies

2005-03-01

443

Plasma Treatment within Dielectric Fluids.  

Science.gov (United States)

A dielectric liquid having entrained bubbles of gas or vapor is subjected to an electric field applied between spaced electrodes (112, 116) which generates microdischarges (and thus plasma) within the bubbles, allowing modification of the properties of th...

2003-01-01

444

Planetary Defense ... - Asteroid Comet Impact Hazards - NASA  

Science.gov (United States)

Mar 1, 2004 ... For a summary of papers from a 4-day AIAA conference held February ... m is less than $400 million, with both ground-based and space-based options possible. .... from concerns about a new generation of nuclear weapons. ...

445

Peter Frampton Talks to Station Crew  

National Aeronautics and Space Administration (NASA)

Rocker Peter Frampton and his band are introduced by astronaut Ron Garan to Commander Mike Fossum and Flight Engineers Satoshi Furukawa and Sergei Volkov aboard the International Space Station during a visit to Mission Control in Houston.

2011-10-17

446

Panel session: Transport of negative ion beams  

Energy Technology Data Exchange (ETDEWEB)

Transport of negative ion beams through plasma is reviewed. The effect of space charge on beam stability and beam emittance is discussed. The approaches to the beam transport problem developed at Los Alamos, Berkeley, Oak Ridge and Culham Laboratory are intercompared. (AIP)

1987-07-30

447

Observatory reports  

Energy Technology Data Exchange (ETDEWEB)

This review covers research done at Lawrence Livermore National Laboratory under DOE contract. Areas of research are as follows: star evolution supernovae, and nucleosynthesis; stellar atmospheres and winds; galaxies and interstellar space; and high-energy astrophysics.

1983-01-01

448

ON NATIONAL AEROIUWICS AND SPACE ADMINISTRATION TEMPE, ARIZOXA  

Science.gov (United States)

ful application of the network technique, GERT, to the analysis of a terminal ... GERT Networks, Mr. David Gallagher-The Use of GERT in Studying Queueing Problems, ... Smith, R. L., "Stochastic Analysis of Personnel Movement in Formal ...

449

Novel Multilocus Measure of Linkage Disequilibrium to Estimate Past Effective Population Size  

UK PubMed Central (United Kingdom)

Linkage disequilibrium (LD) between densely spaced, polymorphic genetic markers in humans and other species contains information about historical population size. Inferring past population size is of...Full Text Available

2003-04-01

450

Nonlinear response of superconductors to alternating fields and currents  

Science.gov (United States)

This report discusses the following topics on superconductivity: nonlinearities in hard superconductors such as surface impedance of a type II superconductimg half space and harmonic generation and intermodulation due to alternating transport currents; and nonlinearities in superconducting weak links such as harmonic generation by a long Josephson Junction in a superconducting slab.

1997-10-08

451

NASA SBIR & STTR 2010 ... - NASA's SBIR & STTR Programs  

Science.gov (United States)

The Heliophysics roadmap: "The Solar and Space Physics of a New Era: ..... Improved materials and manufacturing processes to produce Iridium/Rhenium apogee class ... In addition to batteries, other advanced energy storage/load leveling ...

452

NASA Quest > Space Team Online  

Science.gov (United States)

Jun 28, 2000 ... Right now, my biggest project is working with students. ... RE: [Joni- JoniHarbottle/stilwellMiddleSchool] I have 2 dogs, ... you have to go through the military or any other special services to be the payload scientist? ...

453

NASA JOHNSON SPACE CENTER ORAL HISTORY PROJECT ORAL  

Science.gov (United States)

Jan 15, 2004 ... thought I would have a difficult time working with. ...... they were absolutely right, because everybody said it rained cats and dogs on the orbit ...... We know that in the military. You can ask any military ...

454

Mesencephalic and third ventricle cysts: diagnosis and management in four cases.  

UK PubMed Central (United Kingdom)

Four infants with obstructive hydrocephalus caused by space occupying third ventricle and mesencephalic cysts are reported. Despite immediate shunt insertion in all patients, there was either lack of...Full Text Available

1994-10-01

455

Meeting - Johnson Space Center  

Science.gov (United States)

Nov 2, 1979 ... regular oven, cooktop and hood, $100 each. to NASA 7:30 - 4. Nell x5592. 76. Shasta. 21' travel trailer. (w/extras),. F.P., microwave, ...

456

March 2007 - Discovery Program - NASA  

Science.gov (United States)

The NS together with a gamma ray sensor make up the Gamma- Ray and ... A simplified view of the interactions between incoming cosmic rays and the .... held in Huntsville, Alabama, at the U.S. Space and Rocket Center on January 2830. ...

457

MSI Observation Overview Document Author - Ann Harch, Cornell ...  

Science.gov (United States)

Seq 1 was 8 images spaced 2sec apart, 999 ms man exp, filter 0. ... This region is the 2 sigma ellipsoid. This means, there was 90% chance that ... At this point the ellipse was fat and collapsed as we were still looking more or less ...

458

MRI features of epidural extramedullary hematopoiesis  

Energy Technology Data Exchange (ETDEWEB)

A case of {beta}-thalassemia intermedia with spinal cord compression due to extramedullary hematopoiesis, which was successfully treated by blood transfusion, is presented. Emphasis was made on the MRI appearance of extramedullary hematopoiesis on different pulse sequences. The theories that aimed to explain the involvement of the epidural space by extramedullary hematopoiesis are discussed.

2000-07-01

459

International Space Station Overview - NASA  

Science.gov (United States)

(accumulates & stores brine for disposal). Separator. (separates water from purge gases). ? Purge pump periodically vent ... Reactor Health. Sensor. ( verifies reactor is operating w/n limits) ... Waste and Hygiene Compartment ...

460

Independence of extracellular tortuosity and volume fraction during osmotic challenge in rat neocortex  

UK PubMed Central (United Kingdom)

The structural properties of brain extracellular space (ECS) are summarised by the tortuosity (λ) and the volume fraction (α). To determine if these two parameters were independent,...Full Text Available

2002-07-15

461

Impossibility of a scalar tachyon  

Energy Technology Data Exchange (ETDEWEB)

It is the purpose of this paper to prove that a preferred space direction is coupled with each tachyon and, consequently, scalar tachyons, are impossible in principle. Even the notion of a scalar faster-than-light particle cannot be defined in a relativistically invariant way.

1982-06-01

462

Identification of novel monosodium urate crystal regulated mRNAs by transcript profiling of dissected murine air pouch membranes  

UK PubMed Central (United Kingdom)

IntroductionThe murine air pouch is a bursa-like space that resembles the human synovial membrane. Injection of monosodium urate (MSU) crystals into the pouch elicits an acute inflammatory...Full Text Available

2008-01-01

463

I I I I I I I I I  

Science.gov (United States)

"MAGNETIC FORMING COIL. DESIGN AND DEVELOPMENT". Contract NAS 8 -5434. SUA4MARY R E PORT. Prepared for. GEORGE C. MARSHALL SPACE FLIGHT CENTER ...

464

Hydrodynamic thickening of lubricating fluid layer beneath sliding mesothelial tissues  

UK PubMed Central (United Kingdom)

The delicate mesothelial surfaces of the pleural space and other serosal cavities slide relative to each, lubricated by pleural fluid. In the absence of breathing motion, differences between...Full Text Available

2008-01-01

465

How Different is Different? Criterion and Sensitivity in Face-Space  

UK PubMed Central (United Kingdom)

Not all detectable differences between face images correspond to a change in identity. Here we measure both sensitivity to change and the criterion difference that is perceived as a change in identity....Full Text Available

466

Houstongets - Johnson Space Center - NASA  

Science.gov (United States)

Oct 23, 1992 ... washer, water heater, cooktop, roof, fence, sunroof, auto, 81K mi, runs ok, $2.5 K OBO. x39282 or 335-0641. Want a lucit carpet protector 54" ...

467

Homotopy Normal Maps  

CERN Document Server

Normal maps between discrete groups $N\\rightarrow G$ were characterized[FS] as those which induce a compatible topological group structure on the homotopy quotient $EN\\times_N G$. Here we deal with topological group maps $N\\rightarrow G$ being normal in the same sense as above and hence forming a homotopical analogue to the inclusion of a topological normal subgroup in a reasonable way. We characterize these maps by a compatible simplicial loop space structure on $Bar_\\bullet(N,G)$, invariant under homotopy monoidal functors, e.g. Localizations and Completions. In the course of characterizing homotopy normality, we define a notion of a "homotopy action" similar to an $A_{\\infty}$ action on a space, but phrased in terms of Segal's 'special $\\Delta-$spaces' and seem to be of importance on its own right. As an application of the invariance of normal maps, we give a very short proof to a theorem of Dwyer and Farjoun ...

2010-01-01

468

High-efficiency pump for space helium transfer. Final Technical Report  

Energy Technology Data Exchange (ETDEWEB)

A centrifugal pump was developed for the efficient and reliable transfer of liquid helium in space. The pump can be used to refill cryostats on orbiting satellites which use liquid helium for refrigeration at extremely low temperatures. The pump meets the head and flow requirements of on-orbit helium transfer: a flow rate of 800 L/hr at a head of 128 J/kg. The overall pump efficiency at the design point is 0.45. The design head and flow requirements are met with zero net positive suction head, which is the condition in an orbiting helium supply Dewar. The mass transfer efficiency calculated for a space transfer operation is 0.99. Steel ball bearings are used with gas fiber-reinforced teflon retainers to provide solid lubrication. These bearings have demonstrated the longest life in liquid helium endurance tests under simulated pumping conditions. Technology developed in the project also has application for liquid helium circulation in ...

1991-12-01

469

Heat pumps in urban space heating systems: Energy and environmental aspects  

International Nuclear Information System (INIS)

A statistical survey is conducted of air pollution in the city of Rome (Italy) due to conventional building space heating systems burning fossil fuels. The survey identifies the annual consumption of the different fuels and the relative amounts of the various pollutants released into the atmosphere by the heating plants, e.g., sulfur and nitrogen oxides, carbon monoxide, etc. Comparisons are then made between the ratios of urban heating plant air pollutants produced per tonne of fuel employed and those for ENEL (Italian National Electricity Board) coal, oil and natural gas fired power plants, in order to demonstrate the better environmental performances of the utility operated energy plants. The building space heating system energy consumption and pollution data are then used in a cost benefit analysis favouring the retrofitting of conventional heating systems with heat pump systems to obtain substantial reductions in energy consumption, ...

1991-01-01

470

Goldin says NASA must reach streamlining targets - Johnson Space ...  

Science.gov (United States)

Jan 20, 1995 ... Jenn-Air dowedraft cooktop, staintess steel, coil. $75; telephone ans mach, $25. Eric, x31917. $295; President & First Lady premier plus ...

471

George C. Ma& Marshad Space Flight Center, Alabama - NASA ...  

Science.gov (United States)

tact materials ate Ti-Pd-Ag and the back surface reflector is formed from evaporated .... Ti-Pd-Ag, Dielectric Wraparound. BSR. Evaporated Aluminum ...

472

Geophysical Remote Sensing - The Remote Sensing Tutorial - NASA  

Science.gov (United States)

It was thus actually the fourth stage of the rocket assembly. ... package, and several temperature sensors - was mounted in the cross-lattice frame. ... Earth's geomagnetic field and incoming charged particles from the Sun and extra-solar space. ...

473

General Disclaimer One or more of the Following Statements may ...  

Science.gov (United States)

P".1"..ues OrsedeNle+s Nose aid AtUn*&. SCITRAN. IL Tyr. of RN?/ ow PW" eNfew. Sox 5656. Trawlacio0. 12" ^CTona^ iro aut cce j!"d Space Administration ...

474

Flies In Space - Drosophila - NASA Quest  

Science.gov (United States)

Aqu? va a poder aprender acerca de la Dros?fila Melanogaster, a la cual se le conoce como la mosca de la fruta! Usted podr?. Interpretar por qu? las moscas ...

475

Exotic colliders  

Energy Technology Data Exchange (ETDEWEB)

The motivation, feasibility and potential for two unconventional collider concepts - the Gamma-Gamma Collider and the Muon Collider - are described. The importance of the development of associated technologies such as high average power, high repetition rate lasers and ultrafast phase-space techniques are outlined.

1994-11-01

476

Electric cars and the electricity system  

Energy Technology Data Exchange (ETDEWEB)

The electric power consumption of electric cars and the demand they will pose on electric utilities are considered. The increased amount of travel will require more electric power in summer, while space heating makes larger demands in winter. This leads to nearly flat demand on electric utilities throughout the year. 5 refs.

1981-01-01

477

Economics of Reliability Improvement for Space Launch Vehicles.  

Science.gov (United States)

Present methods for planning reliability improvement of launch vehicles are reviewed. A theoretical criterion for optimum allocation of resources for reliability improvement exists that requires equal marginal failure reduction for all elements to be impr...

1968-01-01

478

Dorsal cortex volume in male side-blotched lizards (Uta stansburiana) is associated with different space use strategies  

UK PubMed Central (United Kingdom)

Spatial abilities have been associated with many ecologically-relevant behaviors such as territoriality, mate choice, navigation and acquisition of food resources. Differential demands on spatial...Full Text Available

2009-07-01

479

Don't Panic! Closed String Tachyons in ALE Spacetimes  

Energy Technology Data Exchange (ETDEWEB)

We consider closed string tachyons localized at the fixed points of noncompact nonsupersymmetric orbifolds. We argue that tachyon condensation drives these orbifolds to flat space or supersymmetric ALE spaces. The decay proceeds via an expanding shell of dilaton gradients and curvature which interpolates between two regions of distinct angular geometry. The string coupling remains weak throughout. For small tachyon VEVs, evidence comes from quiver theories on D-branes probes, in which deformations by twisted couplings smoothly connect non-supersymmetric orbifolds to supersymmetric orbifolds of reduced order. For large tachyon VEVs, evidence comes from worldsheet RG flow and spacetime gravity. For C{sup 2}/Z{sub n}, we exhibit infinite sequences of transitions producing SUSY ALE spaces via twisted closed string condensation from non-supersymmetric ALE spaces. In a T-dual description this provides a ...

2001-08-20

481

Design of the heat receiver for the U.S./Russia solar dynamic power joint flight demonstration  

Energy Technology Data Exchange (ETDEWEB)

A joint US/Russia program is being conducted to develop, fabricate, launch, and operate a solar dynamic demonstration system on Space Station Mir. The goal of the program is to demonstrate and confirm that solar dynamic power systems are viable for future space applications such as the International Space Station Alpha. The major components of the system include a heat receiver, a closed Brayton cycle power conversion unit, a power conditioning and control unit, a concentrator, a radiator, a thermal control system, and a Space Shuttle carrier. This paper discusses the design of the heat receiver component. The receiver comprises a cylindrical cavity, the walls of which are lined with a series of tubes running the length of the cavity. The engine working fluid, a mixture of xenon and helium, is heated by the concentrated sunlight incident on these tubes. The receiver incorporates integral thermal ...

1995-12-31

482

Deformation of CHS model  

Energy Technology Data Exchange (ETDEWEB)

We calculate mass spectrum of CHS model deformed by an exactly marginal operator, and find that there are tachyons which are not localized in the target space. Similar deformation is discussed in another CFT which corresponds to separated NS5-branes. A condensation of the tachyons is briefly argued.

2002-10-07

483

Coulomb scattering for scalar field in Schroedinger picture  

Energy Technology Data Exchange (ETDEWEB)

The scattering of a charged scalar field on Coulomb potential on de Sitter space-time is studied using the solution of the free Klein-Gordon equation. We find that the scattering amplitude is independent of the choice of the picture and in addition the total energy is conserved in the scattering process.

2008-07-31

484

Contingency Space Analysis: An Alternative Method for Identifying Contingent Relations from Observational Data  

UK PubMed Central (United Kingdom)

Descriptive assessment methods have been used in applied settings to identify consequences for problem behavior, thereby aiding in the design of effective treatment programs. Consensus has not been...Full Text Available

2008-01-01

485

Comprehensive Quantification of Signal-to-Noise Ratio and g-Factor for Image-Based and k-Space-Based Parallel Imaging Reconstructions  

UK PubMed Central (United Kingdom)

Parallel imaging reconstructions result in spatially varying noise amplification characterized by the g-factor, precluding conventional measurements of noise from the final...Full Text Available

2008-10-01

486

Comparison of azlocillin, ceftizoxime, cefoxitin, and amikacin alone and in combination against Pseudomonas aeruginosa in a neutropenic-site rabbit model.  

UK PubMed Central (United Kingdom)

The efficacy of beta-lactam antibiotics and amikacin alone and in various combinations against Pseudomonas aeruginosa was studied in a rabbit model simulating a closed-space infection in a locally neutropenic...Full Text Available

1984-05-01

487

Characterization of Two Unique Cholesterol-Rich Lipid Particles Isolated from Human Atherosclerotic Lesions  

UK PubMed Central (United Kingdom)

The authors' laboratory, using histochemicalmethods, previously identified two types of cholesterol-containing lipid particles in the extracellular spaces of human atherosclerotic lesions, one particle...Full Text Available

1990-01-01

488

Chapter 8 - Software ... - JPL Technical Reports Server - NASA  

Science.gov (United States)

These steps are based on work done by the AIAA. Space-Based Observation Systems Committee on Standards (SBOS COS) as well as work done in this ..... Surface Weapons Center, Code B-10, Dahlgren, VA, 22448. Although it had many ...

489

Branch morphology in young poplar clones on floodplain sites in ...  

Science.gov (United States)

Sep 28, 2011 ... Description: Four Populus clones were grown in central Missouri for 2 years at 1 x 1 m spacing to study total biomass production on floodplain ...

490

Be stars  

Energy Technology Data Exchange (ETDEWEB)

Research on Be stars from the early work of Merrill and Struve to the present is reviewed, including recent observations from space. A number of models which have been proposed to explain the Be phenomenon are discussed, and the evolutionary status of Be stars is considered. 126 references.

1988-07-01

491

Bacterial Fouling in a Model Core System  

UK PubMed Central (United Kingdom)

We have used a sintered glass bead core to simulate the spaces and surfaces of reservoir rock in studies of the bacterial plugging phenomenon that affects waterflood oil recovery operations. The passage...Full Text Available

1985-03-01

492

Asymptotic functions and multiplication of distributions  

International Nuclear Information System (INIS)

Considered is a new type of generalized asymptotic functions, which are not functionals on some space of test functions as the Schwartz distributions. The definition of the generalized asymptotic functions is given. It is pointed out that in future the particular asymptotic functions will be used for solving some topics of quantum mechanics and quantum theory.

1976-01-26

493

Asia - Goddard Earth Science Data and Information Services Center ...  

Science.gov (United States)

Sep 9, 2009 ... You are here: GES DISC Home Geomorphology from Space By Location Landforms by Location: Asia. Info. Landforms by Location: Asia. KEY, ASIA ...

494

Archive | June 29, 2010 | Armed with Science  

Science.gov (United States)

He said due to DoD's early involvement in the creation of the Internet (a product of DARPA), it has more address space at its disposal than most other organizations worldwide....

2011-08-28

495

An Instrumented Range Meeting the Requirements of a Wound Ballistics Small Arms Program.  

Science.gov (United States)

Instrumentation, equipment, and space requirements are outlined which would satisfy a portion of the needs of the Wound Ballistics Program of research into the terminal behavior of missiles from a variety of antipersonnel munitions (fragments, flechettes,...

1968-01-01

496

AeroSpace Information for a Changing World - NASA Technical ...  

Science.gov (United States)

Probing Neutron Star Evolution with Gamma Rays Online Source: Click to View PDF File [PDF Size: 217 KB] Author: Wijers, Ralph A. M. J. ...

497

APOD: April 24, 1996 - Giant Cluster Bends, Breaks Galaxy Images  

Science.gov (United States)

Space Telescope is six years old today! Tomorrow's picture: In the Center of the Whirlpool | Archive | Index | Search | Glossary | Education | About APOD | See Explanation....

2011-10-07

498

AN INFORMATION/NAVIGATION AID FOR COMPLEX INDOOR SPACE FEASIBILITY STUDY TO ESTABLISH OLDER PEOPLE'S NEEDS  

Environmental Research Database

Objectives1. To identify with older people the problems which they encounter in finding their way about public building/spaces.~%~2. To produce ideas, in consultation with older people, for an information/navigation aid that might facilitate their use and enjoyment of public buildings/spaces, notably hospitals, large shops, railway stations, airports.~%~3. To develop an emulation model of the information/navigation aid~%~4. To monitor use of the model by older people~%~5. To identify further research~%~6. [continued...]DescriptionThe growth in the number of older people offers scope for the development of customised information/navigation aids to help them to find their way around complex public spaces. New technology however is unlikely to be taken up by older people unless it is acceptable to them. The research will involve engineers in designing, testing and modifying a model of such an aid in conjunction with a sample ...

1999-01-31

499

8. Application of radionuclide X-ray fluorescence analysis in other fields of science and technology  

International Nuclear Information System (INIS)

Certain applications are described of radionuclide X-ray fluorescence analysis in the ore dressing industry, in the manufacture of building materials, in metallurgy, pharmacy, in the chemical, photographic and paper industries, in space exploration, in archeology and for measuring the thicknesses of thin layers of coatings. (ES).

1983-12-01

500

48 CFR 228.370 - Additional clauses.  

Science.gov (United States)

...Acquisition Regulations System 3 2010-10-01...Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF...assumption of risk for transportation by conveyance on...Missiles, and Space Launch Vehicles,...

2010-10-01