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951.
Beginning in 1995, a team of 3-D engineering visualization experts assembled at the Lockheed Martin Space Systems Company and began to develop innovative virtual prototyping simulation tools for performing ground processing and real-time visualization of design and planning of aerospace missions. At the University of Colorado, a team of 3-D visualization experts also began developing the science of 3-D visualization and immersive visualization at the newly founded British Petroleum (BP) Center for visualization, which began operations in October, 2001. BP acquired ARCO in the year 2000 and awarded the 3-D flexible IVE developed by ARCO (beginning in 1990) to the University of Colorado, CU, the winner in a competition among 6 Universities. CU then hired Dr. G. Dorn, the leader of the ARCO team as Center Director, and the other experts to apply 3-D immersive visualization to aerospace and to other University Research fields, while continuing research on surface interpretation of seismic data and 3-D volumes. This paper recounts further progress and outlines plans in Aerospace applications at Lockheed Martin and CU. 相似文献
952.
Trainer MG Pavlov AA Curtis DB McKay CP Worsnop DR Delia AE Toohey DW Toon OB Tolbert MA 《Astrobiology》2004,4(4):409-419
An organic haze layer in the upper atmosphere of Titan plays a crucial role in the atmospheric composition and climate of that moon. Such a haze layer may also have existed on the early Earth, providing an ultraviolet shield for greenhouse gases needed to warm the planet enough for life to arise and evolve. Despite the implications of such a haze layer, little is known about the organic material produced under early Earth conditions when both CO(2) and CH(4) may have been abundant in the atmosphere. For the first time, we experimentally demonstrate that organic haze can be generated in different CH(4)/CO(2) ratios. Here, we show that haze aerosols are able to form at CH(4) mixing ratios of 1,000 ppmv, a level likely to be present on early Earth. In addition, we find that organic hazes will form at C/O ratios as low as 0.6, which is lower than the predicted value of unity. We also show that as the C/O ratio decreases, the organic particles produced are more oxidized and contain biologically labile compounds. After life arose, the haze may thus have provided food for biota. 相似文献
953.
954.
L Narici V Bidoli M Casolino M P De Pascale G Furano A Morselli P Picozza E Reali R Sparvoli S Licoccia P Romagnoli E Traversa W G Sannita A Loizzo A Galper A Khodarovich M G Korotkov A Popov N Vavilov S Avdeev V P Salnitskii O I Shevchenko V P Petrov K A Trukhanov M Boezio W Bonvicini A Vacchi N Zampa R Battiston G Mazzenga M Ricci P Spillantini G Castellini P Carlson C Fuglesang 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2003,31(1):141-146
The ALTEA project participates to the quest for increasing the safety of manned space flights. It addresses the problems related to possible functional damage to neural cells and circuits due to particle radiation in space environment. Specifically it aims at studying the functionality of the astronauts' Central Nervous Systems (CNS) during long space flights and relating it to the peculiar environments in space, with a particular focus on the particle flux impinging in the head. The project is a large international and multidisciplinary collaboration. Competences in particle physics, neurophysiology, psychophysiology, electronics, space environment, data analyses will work together to construct the fully integrated vision electrophysiology and particle analyser system which is the core device of the project: an helmet-shaped multi-sensor device that will measure concurrently the dynamics of the functional status of the visual system and passage of each particle through the brain within a pre-determined energy window. ALTEA is scheduled to fly in the International Space Station in late 2002. One part of the multi-sensor device, one of the advanced silicon telescopes, will be launched in the ISS in early 2002 and serve as test for the final device and as discriminating dosimeter for the particle fluences within the ISS. 相似文献
955.
Trinh EH 《Acta Astronautica》2003,53(4-10):317-327
The restructuring of the research capabilities of the International Space Station has forced a reassessment of the Physical Sciences research plans and a re-targeting of the major scientific thrusts. The combination of already selected peer-reviewed flight investigations with the initiation of new research and technology programs will allow the maximization of the ISS scientific and technological potential. Fundamental and applied research will use a combination of ISS-based facilities, ground-based activities, and other experimental platforms to address issues impacting fundamental knowledge, industrial and medical applications on Earth, and the technology required for human space exploration. The current flight investigation research plan shows a large number of principal investigators selected to use the remaining planned research facilities. 相似文献
956.
957.
A continuing challenge for scientists is to keep K-12 teachers informed about new scientific developments. Over the past few years, this challenge has increased as new research findings have come from the field of astrobiology. In addition to trying to keep abreast of these new discoveries, K-12 teachers must also face the demands of the content and pedagogical goals imposed by state and national science education standards. Furthermore, many teachers lack the scientific content knowledge or training in current teaching methods to create their own activities or to implement appropriately new teaching materials designed to meet the standards. There is a clear need for special courses designed to increase the scientific knowledge of K-12 science teachers. In response to this need, the authors developed a suite of innovative, classroom-ready lessons for grades 5-12 that emphasize an active engagement instructional strategy and focus on the recent discoveries in the field of astrobiology. They further created a graduate-level, Internet-based distance-learning course for teachers to help them become familiar with these astrobiology concepts and to gain firsthand experience with the National Science Education Standards-based instructional strategies. 相似文献
958.
A. P. Tyutnev A. N. Doronin V. S. Saenko D. N. Sadovnichii E. D. Pozhidaev 《Cosmic Research》2002,40(2):129-132
A simplified theory of the electrification of polymer films, which permits estimation of the internal electric fields of films irradiated by monoenergetic electrons simulating real streams of plasma electrons during magnetic substorms at a geosynchronous orbit, is suggested. To determine the depth behavior of the forward current and the dosage rate in the irradiated polymer, numerical calculations are made by the Monte Carlo technique. The appearance of electrostatic discharges in thin (5 m) mylar films is shown to be very probable in the orbit's shadow sector under magnetic substorm conditions. 相似文献
959.
The purpose of this study is to examine human adaptation of a three members' crew during a 135 days MIR flight simulation and to compare and validate psychological methods for monitoring and support in flight. The main findings showed that isolation was not a key factor for the subjects who were more concerned by recreational activities, family, and work. The individual reactions to stress of the crew members were to project their problems on the others. These reactions had some consequences upon the group: Although the three subjects developed a weak tendency to "group think", one of the crew members was considered as less integrated to the group by the other two subjects, who, however, acted to protect (successfully) the general cohesion and mood of the crew. From a methodological point of view, baseline data predicted the difficulties that occurred for one of the crew member. Both quantitative and qualitative tools were adequate, although qualitative tests gave a closer approach to the actual situation that developed during the simulation. 相似文献
960.
Calculations of total dose and dose equivalent as a function of time since the start of the event are presented for four of the major solar particle events that occurred during the period from August to December 1989. Results are presented for exposures to the skin, ocular lens and bone marrow shielded by a nominal thickness of aluminum shielding, comparable to that provided by a spacesuit. The calculated curves of organ dose and dose equivalent versus time are parameterized using a Weibull functional form for the fitting equation. The fitting parameters are determined using least squares regression techniques. These results provide a useful starting point for the development of methods to predict the cumulative doses and times to reach various dose limits from a limited number of dose measurements early in a solar particle event. 相似文献