“脑资源”枯竭 美国航宇公司人才告急

AVIATIONWEEK》》&SPACETECHNOLOGYBrainDrainThreatensAerospaceVitality高级工程人员的短缺正在严重削弱美国航空界的活力，这种情况短期内难以得到解决美国航字工业正在面临一个越来越严重的问题，可以说是一个危机，而且按照一些资深观察家的观点，这种情况还看不到什么时候可以得到改善的迹象。这个危机被称为‘脑资源枯竭”，又称为“智力外流”。随着新兴电子商务公司的不断涌现，如何吸引高技术人才以及留住高智商技术人员已越来越困难，特别在一些关键的行业，如电子、软件和系统工程等更是突出，人才短缺已经对工业…     

欧洲的研究和发展计划旨在更清洁的发动机

AVIATIONWEEK》》&SPACETECHNOLOGYEuropeanRεDprojectsTargetCleanerEngines为在未来的民用发动机市场上占更多的份额，欧洲发动机公司正在实施环保型发动机研究计划，目标是大大减少CO。和NOX的排放，并降低拥有费用欧洲委员会已同意投资两项研究计划，旨在为商用飞机研究更清洁和更高效的发动机。这些称为技术平台的飞机发动机计划是根据欧洲委员会研究指挥部第5框架计划进行的，这些计划从2000年到2004年实施，是提高欧洲航字工业竞争性的一系列主要研究和发展计划的首批计划。根据第5框架计划投资的其他技术平台计划…     

Analysis of a spacecraft life support system for a Mars mission

This report summarizes a trade study conducted as part of the Fall 2002 semester Spacecraft Life Support System Design course (ASEN 5116) in the Aerospace Engineering Sciences Department at the University of Colorado. It presents an analysis of current life support system technologies and a preliminary design of an integrated system for supporting humans during transit to and on the surface of the planet Mars. This effort was based on the NASA Design Reference Mission (DRM) for the human exploration of Mars [NASA Design Reference Mission (DRM) for Mars, Addendum 3.0, from the world wide web: http://exploration.jsc.nasa.gov/marsref/contents.html.]. The integrated design was broken into four subsystems: Water Management, Atmosphere Management, Waste Processing, and Food Supply. The process started with the derivation of top-level requirements from the DRM. Additional system and subsystem level assumptions were added where clarification was needed. Candidate technologies were identified and characterized based on performance factors. Trade studies were then conducted for each subsystem. The resulting technologies were integrated into an overall design solution using mass flow relationships. The system level trade study yielded two different configurations--one for the transit to Mars and another for the surface habitat, which included in situ resource utilization. Equivalent System Mass analyses were used to compare each design against an open-loop (non-regenerable) baseline system.     

The first cell membranes

Organic compounds are synthesized in the interstellar medium and can be delivered to planetary surfaces such as the early Earth, where they mix with endogenous species. Some of these compounds are amphiphilic, having polar and nonpolar groups on the same molecule. Amphiphilic compounds spontaneously self-assemble into more complex structures such as bimolecular layers, which in turn form closed membranous vesicles. The first forms of cellular life required self-assembled membranes that were likely to have been produced from amphiphilic compounds on the prebiotic Earth. Laboratory simulations show that such vesicles readily encapsulate functional macromolecules, including nucleic acids and polymerases. The goal of future investigations will be to fabricate artificial cells as models of the origin of life.     

精益理论在维修领域的实践

维修企业向精益和六西格玛转变,可以缩短交付周期和节省成本,但这个过程需要花数百万美元并做出长期的努力。     

GAO要求严格审查“代码共享”营运

据美国联邦审计总署(GAO)的报告指出,美国运输部即将颁布新的条例,旨在更为准确地评估“代码共享”(Code-Sharing)战略联盟对美国民航业的影响,并确定反垄断豁免权是否能鼓励新的“开放天空”协议的签署.该报告还指出,目前已有的数据尚不足以精确地确定各种联盟短期内对票价结构的实际影响是什么,是否会减弱或加剧长期的竞争,从而导致票价的降低或升高.     

Human factors in underwater systems

Applications of human factors to undersea engineering and the relationship to aerospace science are explored. Cooperative ventures include the TEKTITE underwater habitat and development of better procedures to prevent decompression sickness. Other research involved the use of alternate gases in diving systems, remote-operation vehicles, and diving system tests.     

用STARE-TRIAD联合观测对磁层-电离层不完全耦合的实例研究

本文用STARE-TRIAD联合观测的一个实例研究磁层-电离层不完全耦合现象.实例中观测的电场、场向电流和推出的Pederson电导率在Harang不连续区的分布与用Kan-Lee磁层-电离层不完全耦合理论的预测值符合得很好.这支持了该理论所说的在电等位U-位形低纬侧有S-位形存在以及与之相应的电离层电导率的第二增强区和电场凹陷区等现象.STARE的其他观测事实说明这些现象具有一定的普遍意义.      

更加敏捷的军机维修

“灵活支援”和“自主后勤”代表了军机维修业务的新趋势———更快、更好、更便宜。相应地带来业务模式的转变。官方民间合作(PPP)和基于性能的后勤(PBL)变得越来越重要