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101.
许为陈勇 《民用飞机设计与研究》2014,(3):5-11
人为差错成为导致民用飞机重大事故的主要原因已经是不争的事实。对人为差错发生的原因及其预防措施已有许多研究和建议。侧重从民机驾驶舱设计和适航角度,并结合增补的FAA和EASA FAR/CS 25.1302适航条款,分析和探讨为减少由设计引发的飞行员人为差错所面临的挑战和途径,并对开展这方面的工作提出一系列框架性建议。 相似文献
102.
静态图像压缩领域提出了众多图像质量客观评估方法,但对于各种客观评估方法与主观感受相符程度的研究仍有不足。为此,文章设计了一种评价客观评估方法的测评方法:按特定原则建立相对完备的测评图像库,以实际观测得到的主观分数为参考,以客观评估方法的评价分数为测评对象,通过对比同一压缩算法不同压缩倍数、不同压缩算法主观质量相近情况下各种评估方法的表现,以及依据VQEG报告的度量准则所求的度量结果,对客观评估方法的性能进行评价。同时,文章以PSNR和SSIM为例进行了测评,结果表明SSIM各项指标优于PSNR,与现有结论一致。 相似文献
103.
In contemporary orbital missions, workloads are so high and varied that crew may rarely experience stretches of monotony. However, in historical long duration missions, occurrences of monotony were, indeed, reported anecdotally by crew. Of the effective countermeasures that appear to be at hand, many rely on visual or logistical proximity to the Earth, and are not feasible in the remote context of an extended deep space mission scenario. There, particularly in- and outbound cruising stages would be characterised by longer, comparably uneventful periods of low workload, coupled with confinement and unchanging vehicle surroundings. 相似文献
104.
In 2009 President Obama proposed a budget for the National Aeronautics and Space Administration (NASA) that canceled the Constellation program and included the development of commercial crew transportation systems into low Earth orbit. This significant move to shift human spaceflight into the private sector sparked political debate, but much of the discourse has focused on impacts to “safety.” Although no one disputes the importance of keeping astronauts safe, strategies for defining safety reveal contrasting visions for the space program and opposing values regarding the privatization of U.S. space exploration. In other words, the debate over commercial control has largely become encoded in arguments over safety. Specifically, proponents of using commercial options for transporting astronauts to the International Space Station (ISS) argue that commercial vehicles would be safe for astronauts, while proponents of NASA control argue that commercial vehicles would be unsafe, or at least not as safe as NASA vehicles. The cost of the spaceflight program, the technical requirements for designing a vehicle, the track record of the launch vehicle, and the experience of the launch provider are all incorporated into what defines safety in human spaceflight. This paper analyzes these contested criteria through conceptual lenses provided by fields of science and technology policy (STP) and science, technology, and society (STS). We ultimately contend that these differences in definition result not merely from ambiguous understandings of safety, but from intentional and strategic choices guided by normative positions on the commercialization of human spaceflight. The debate over safety is better considered a proxy debate for the partisan preferences embedded within the dispute over public or private spaceflight. 相似文献
105.
针对现代航空中存在的沟通、压力、团队合作以及生理和心理方面的人为因素问题,采用模糊层次分析法对其重要性进行识别.结果显示,语音信息沟通、机组资源管理、书面信息沟通、空管班组资源管理、疲劳、情景意识、维修班组资源管理、过分自信和满足在现代航空人为因素问题中占有比较突出的地位. 相似文献
106.
Blanca Mendoza Salvador Sánchez de la Peña 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
The study of the possible effect of solar variability on living organisms is one of the most controversial issues of present day science. It has been firstly and mainly carried on high latitudes, while at middle and low latitudes this study is rare. In the present review we focused on the work developed at middle and low geomagnetic latitudes of America. At these geomagnetic latitudes the groups consistently dedicated to this issue are mainly two, one in Cuba and the other in Mexico. 相似文献
107.
Early Warning Aircraft(EWA) are the main force for air detection and its Human-Machine Interface(HMI) should be designed to support task efficiency and safety. With the application of advanced input method and interface design in EWA, little is known about their actual usability in terms of human factors and ergonomics. The aim of this study was to investigate the effects of the input method and display mode of the situation map on EWA reconnaissance task performance with different information c... 相似文献
108.
Stéphane Grès Michel Tognini Gilles Le Cardinal Zyed Zalila Guillaume Gueydan 《Acta Astronautica》2014
This paper proposes an approach for a complex and innovative project requiring international contributions from different communities of knowledge and expertise. Designing a safe and reliable architecture for a manned mission to Mars or the Asteroids necessitates strong cooperation during the early stages of design to prevent and reduce risks for the astronauts at each step of the mission. The stake during design is to deal with the contradictions, antagonisms and paradoxes of the involved partners for the definition and modeling of a shared project of reference. As we see in our research which analyses the cognitive and social aspects of technological risks in major accidents, in such a project, the complexity of the global organization (during design and use) and the integration of a wide and varie d range of sciences and innovative technologies is likely to increase systemic risks as follows: human and cultural mistakes, potential defaults, failures and accidents. We identify as the main danger antiquated centralized models of organization and the operational limits of interdisciplinarity in the sciences. Beyond this, we can see that we need to take carefully into account human cooperation and the quality of relations between heterogeneous partners. Designing an open, self-learning and reliable exploration system able to self-adapt in dangerous and unforeseen situations implies a collective networked intelligence led by a safe process that organizes interaction between the actors and the aims of the project. Our work, supported by the CNES (French Space Agency), proposes an innovative approach to the coordination of a complex project. 相似文献
109.
110.
Ehlmann BL Chowdhury J Marzullo TC Collins RE Litzenberger J Ibsen S Krauser WR DeKock B Hannon M Kinnevan J Shepard R Grant FD 《Acta Astronautica》2005,56(9-12):851-858
Mars is a compelling astrobiological target, and a human mission would provide an opportunity to collect immense amounts of scientific data. Exploration alone, however, cannot justify the increased risk. Instead, three factors drive a human mission: economics, education, and exploration. A human mission has a unique potential to inspire the next generation of young people to enter critically needed science and engineering disciplines. A mission is economically feasible, and the research and development program put in place for a human mission would propel growth in related high-technology industries. The main hurdles are human physiological responses to 1–2 years of radiation and microgravity exposure. However, enabling technologies are sufficiently mature in these areas that they can be developed within a few decade timescale. Hence, the decision of whether or not to undertake a human mission to Mars is a political decision, and thus, educational and economic benefits are the crucial factors. 相似文献