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1.
Dave Wright   《Space Policy》2002,18(1):67
The UK space industry is an important part of the British economy and likely to become more so, but it needs well-educated graduates, government support and investment. Such an effort would be aided by an educated public. Education is an important part of a successful space industry policy. The Space Education Council, supported by the BNSC, is doing important work talking to the public about space. This article argues that there is a need for more space education work and reports on the Space Education Council's recent symposium.  相似文献   
2.
The assessment of personality is recognized by space agencies as an approach to identify candidates likely to perform optimally during spaceflights. In the use of personality scales for selection, the impact of social desirability (SD) has been cited as a concern. Study 1 addressed the impact of SD on responses to the Personality Characteristic Inventory(PCI) and NEO-FFI. This was achieved by contrasting scores from active astronauts (N=65) with scores of successful astronaut applicants (N=63), and between pilots applicants (N=1271) and pilot research subjects (N=120). Secondly, personality scores were correlated with scores on the Marlow Crown Social Desirability Scale among applicants to managerial positions (N=120). The results indicated that SD inflated scores on PCI scales assessing negative interpersonal characteristics, and impacted on four of five scales in NEO-FFI. Still, the effect sizes were small or moderate. Study 2 addressed performance implications of SD during an assessment of males applying to work as rescue personnel operations in the North Sea (N=22). The results showed that SD correlated negatively with cognitive test performance, and positively with discrepancy in performance ratings between self and two observers. In conclusion, caution is needed in interpreting personality scores in applicant populations. SD maybe a negative predictor for performance under stress.  相似文献   
3.
Waltham D 《Astrobiology》2011,11(2):105-114
Planetary anthropic selection, the idea that Earth has unusual properties since, otherwise, we would not be here to observe it, is a controversial idea. This paper proposes a methodology by which to test anthropic proposals by comparison of Earth to synthetic populations of Earth-like planets. The paper illustrates this approach by investigating possible anthropic selection for high (or low) rates of Milankovitch-driven climate change. Three separate tests are investigated: (1) Earth-Moon properties and their effect on obliquity; (2) Individual planet locations and their effect on eccentricity variation; (3) The overall structure of the Solar System and its effect on eccentricity variation. In all three cases, the actual Earth/Solar System has unusually low Milankovitch frequencies compared to similar alternative systems. All three results are statistically significant at the 5% or better level, and the probability of all three occurring by chance is less than 10(-5). It therefore appears that there has been anthropic selection for slow Milankovitch cycles. This implies possible selection for a stable climate, which, if true, undermines the Gaia hypothesis and also suggests that planets with Earth-like levels of biodiversity are likely to be very rare.  相似文献   
4.
经过理论与实践的证实,空间误差补偿方法被认定为是可以大幅度提高机床工作精度的实用方法。VEC对机床的测量、调校贯穿于机床在其工作空间内运动的整个过程,所以使用VEC方法既可以对动态误差进行实时补偿,又可以测得机床运动时相关的几何效应,从而对机床误差实行更为精准的补偿。  相似文献   
5.
Dave Wright   《Space Policy》2008,24(1):48-49
Despite public enthusiasm, space in the UK is perceived as lacking support from the government and policy often seems incoherent. A knock-on effect is the low number of students pursuing study or careers in science and engineering. Lately, however, space activity has been receiving greater attention from official circles and, in an effort to capitalise on this, a group of individuals has come up with a plan to hold an annual conference on UK space policy. The aims and framework of the conference are described.  相似文献   
6.
The Expendable Launch Systems division of The Boeing Company is well into the development of the new family of Delta IV launch vehicles to support commercial and government missions. The Delta IV adds to the existing Delta family of vehicles, the Delta II in four configurations and the Delta III with twice the performance of the Delta II.The addition of the Delta IV adds five vehicles to the Delta family: the Delta IV medium, three Delta IV Medium-Plus vehicles with solid rocket augmentation, and the Delta IV Heavy vehicles. This family now addresses the full market range of payload requirements from 2,000 to 29,000 pounds to geosynchronous transfer orbit (GTO). Full-scale commercial development was initiated in 1997, with the first Delta flight planned for the second quarter of 2001. This paper presents the status of the development program of the launch vehicles, the new green field, focused factory for common booster core production at Decatur, Alabama, the new launch facility construction at Cape Canaveral Air Force Station and Vandenberg Air Force Base, and the new LO2/LH2 RS-68 common booster core engine. The status of the Delta III return to flight is also presented.  相似文献   
7.
Space solar power (SSP) has been broadly defined as the collection of solar energy in space and its wireless transmission for use on earth. This approach potentially gives the benefit of provision of baseload power while avoiding the losses due to the day/night cycle and tropospheric effects that are associated with terrestrial solar power. Proponents have contended that the implementation of such systems could offer energy security, environmental, and technological advantages to those who would undertake their development. Among recent implementations commonly proposed for SSP, the modular symmetrical concentrator (MSC) and other modular concepts have received considerable attention. Each employs an array of modules for performing conversion of concentrated sunlight into microwaves or laser beams for transmission to earth. While prototypes of such modules have been designed and developed previously by several groups, none have been subjected to the challenging conditions inherent to the space environment and the possible solar concentration levels in which an array of modules might be required to operate. The research described herein details our team's efforts in the development of photovoltaic arrays, power electronics, microwave conversion electronics, and antennas for microwave-based “sandwich” module prototypes. The implementation status and testing results of the prototypes are reviewed.  相似文献   
8.
The LISA (Laser Interferometer Space Antenna) mission has been selected by the European Space Agency’s Science Programme Committee as the third large-class mission of the Cosmic Vision Programme, addressing the science theme of the Gravitational Universe. With a planned launch date in 2034, LISA will be the first ever space-borne Gravitational Wave observatory, relying on laser interferometry between three spacecraft orbiting the Sun in a triangular formation. Airbus is currently leading an industrial Phase A system study on behalf of the European Space Agency. The paper will address the astrodynamics challenges associated with the LISA constellation design, driven by tight requirements on the geometric quality metrics of the near equilateral formation.  相似文献   
9.
The large-scale coronal magnetic fields of the Sun are believed to play an important role in organizing the coronal plasma and channeling the high and low speed solar wind along the open magnetic field lines of the polar coronal holes and the rapidly diverging field lines close to the current sheet regions, as has been observed by the instruments aboard the Ulysses spacecraft from March 1992 to March 1997. We have performed a study of this phenomena within the framework of a semi-empirical model of the coronal expansion and solar wind using Spartan, SOHO, and Ulysses observations during the quiescent phase of the solar cycle. Key to this understanding is the demonstration that the white light coronagraph data can be used to trace out the topology of the coronal magnetic field and then using the Ulysses data to fix the strength of the surface magnetic field of the Sun. As a consequence, it is possible to utilize this semi-empirical model with remote sensing observation of the shape and density of the solar corona and in situ data of magnetic field and mass flux to predict values of the solar wind at all latitudes through out the solar system. We have applied this technique to the observations of Spartan 201-05 on 1–2 November, 1998, SOHO and Ulysses during the rising phase of this solar cycle and speculate on what solar wind velocities Ulysses will observe during its polar passes over the south and the north poles during September of 2000 and 2001. In order to do this the model has been generalized to include multiple streamer belts and co-located current sheets. The model shows some interesting new results. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
10.
Dave Anderson 《Acta Astronautica》1999,44(7-12):593-606
To sustain the rate of extravehicular activity (EVA) required to assemble and maintain the International Space Station, we must enhance our ability to plan, train for, and execute EVAs. An underlying analysis capability has been developed to ensure EVA access to all external worksites as a starting point for ground training, to generate information needed for on-orbit training, and to react quickly to develop contingency EVA plans, techniques, and procedures. This paper describes the use of computer-based EVA worksite analysis techniques for EVA worksite design. EVA worksite analysis has been used to design 80% of EVA worksites on the U.S. portion of the International Space Station. With the launch of the first U.S. element of the station, EVA worksite analysis is being developed further to support real-time analysis of unplanned EVA operations. This paper describes this development and deployment of EVA worksite analysis for International Space Station (ISS) mission support.  相似文献   
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