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661.
Superconducting magnetic energy storage (SMES) is an emerging technology that is expected to provide a means of storing electrical energy for use during peak demand periods. Pacific Northwest Laboratory (PNL) has estimated benefits and costs associated with the use of SMES technology and has provided insight into the overall future potential of SMES in the service area of the Bonneville Power Administration (BPA) and on systems that connect and exchange power with BPA  相似文献   
662.
The growing perception that with cutbacks in the military and the changing international economic environment, the military must rely on commercial industries in order to afford the next generation of high-performance and high-reliability military systems is discussed. One issue associated with the question of whether an industrial base for the military can be provided and maintained without major changes in the operation of both the government and commercial industry is examined, namely, whether commercial standards can effectively supplant military standards and still provide high performance and reliability for military missions  相似文献   
663.
The CDS and SUMER instruments will make extensive use of spectroscopic diagnostics to determine the physical parameters of the solar transition region and corona. A great deal of effort is going into the development of these techniques to ensure that they are accurate. This requires interfacing solar analysis programs with the best available atomic data calculations. Recent developments in this work will be presented, with specific examples of useful spectral line ratios.  相似文献   
664.
665.
A controlled ecological life-support system (CELSS) is required to sustain life for long-duration space missions. The challenge is preparing a wide variety of tasty, familiar, and nutritious foods from CELSS candidate crops under space environmental conditions. Conventional food processing technologies will have to be modified to adapt to the space environment. Extrusion is one of the processes being examined as a means of converting raw plant biomass into familiar foods. A nutrition-improved pasta has been developed using cowpea as a replacement for a portion of the durum semolina. A freeze-drying system that simulates the space conditions has also been developed. Other technologies that would fulfill the requirements of a CELSS will also be addressed.  相似文献   
666.
J E Urban 《Acta Astronautica》2000,47(10):775-780
Bacteria that contain magnetosomes display magnetotaxis and align themselves to the earth's magnetic field. When magnetotactic bacteria were first isolated several decades ago it was presumed that geomagnetic orientation allowed magnetotactic bacteria to orient themselves downward towards sediments where the habitat is favorable to their growth and metabolism. As more species of magnetotactic bacteria have been isolated and studied, differences in magnetotactic responses have been observed which suggested that the primary role of magnetosomes might simply be to enhance a microorganism's response to gravity. To resolve if gravity influences magnetotactic behavior in bacteria, Magnetospirillum magnetotacticum was used to examine magnetotaxis in the absence of gravity. Experiments to compare the orientation of bacteria to north- or south-pole magnets were conducted in normal gravity and in the microgravity environments aboard the Space Shuttle and Space Station MIR. In each of the microgravity situations studied, bacteria were impaired in their ability to orient to magnets and the failure to exhibit magnetotaxis appeared to be a function of the loss of magnetosomes. The disappearance of aggregated magnetosomes seemed to correlate with a general loss of cellular integrity in microgravity.  相似文献   
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668.
The 1990s have been stressful for commercial airline industry: fierce competition has caused the demise of several carriers. The resulting drive to slash operating expenses has bolstered development of avionics industry standards for automated test equipment. Rockwell's Collins Air Transport Division (CATD) has begun to market compliant test gear that airline maintenance departments wishing to acquire modern high performance test systems without the development cost penalty have eagerly received. A similar situation now confronts the military. The various branches can no longer justify the maintenance of independent autotest architectures. This paper describes the CATD implementation of the commercial-standard architecture; shows how we have designed the system to avoid obsolescence; and indicates the considerations that are necessary for adapting it to military scenarios  相似文献   
669.
This paper presents profiles of 12 airborne and spaceborne Synthetic Aperture Radar (SAR) imaging systems. This information is intended to help potential users evaluate the systems for specific applications. The systems profiled in this article can be used for commercial purposes; some have been built specifically for commercial use while others also serve as science and research tools, Both domestic and foreign systems designed for government agencies and private industry are profiled. Nine of these systems are currently operational; two systems are scheduled to begin service in the near future. A third system is no longer active, but archive data are commercially available  相似文献   
670.
NASA's pair of Galileo spacecraft arrived at Jupiter on 7 December 1995. The Probe descended into the upper Jovian atmosphere, performing its planned sequence of scientific measurements of the properties of that medium for about an hour. This Probe has been the most ambitious planetary entry vehicle to date. It evolved over several years of planning and construction, its launch was postponed many times, for a variety of reasons; and it required more than 6 years of travel after launch to reach the planet. Its electrical power was provided by a primary Li-SO2 battery, supplemented with two thermal batteries (CaCrO4-Ca) used for firing pyrotechnic initiators during the atmospheric entry. These power sources were designed to be robust, to assure they would perform their intended function after surviving several years in space. This paper discusses the final production, qualification, and the systems testing of these batteries prior to and following launch. Their excellent performance at Jupiter confirmed their life enhancement design features  相似文献   
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