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91.
Low earth orbit has become increasingly congested as the satellite population has grown over the past few decades, making orbital debris a major concern for the operational stability of space assets. This congestion was highlighted by the collision of the Iridium 33 and Cosmos 2251 satellites in 2009. This paper addresses the current state of orbital debris regulation in the United States and asks what might be done through policy change to mitigate risks in the orbital debris environment. A brief discussion of the nature of orbital debris addresses the major contributing factors including size classes, locations of population concentrations, projected satellite populations, and current challenges presented in using post-mission active debris removal to mitigate orbital debris. An overview of the current orbital debris regulatory structure of the United States reveals the fragmented nature of having six regulating bodies providing varying levels of oversight to their markets. A closer look into the regulatory policy of these agencies shows that, while they all take direction from The U.S. Government Orbital Debris Mitigation Standard Practices, this policy is a guideline with no real penalty for non-compliance. Various policy solutions to the orbital debris problem are presented, ranging from a business as usual approach to a consolidated regulation system which would encourage spacecraft operator compliance. The positive aspects of these options are presented as themes that would comprise an effective policy shift towards successful LEO conservation. Potential economic and physical limitations to this policy approach are also addressed. 相似文献
92.
《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014,54(2):221-240
The pace of scientific exploration of our solar system provides ever-increasing insights into potentially habitable environments, and associated concerns for their contamination by Earth organisms. Biological and organic-chemical contamination has been extensively considered by the COSPAR Panel on Planetary Protection (PPP) and has resulted in the internationally recognized regulations to which spacefaring nations adhere, and which have been in place for 40 years. The only successful Mars lander missions with system-level “sterilization” were the Viking landers in the 1970s. Since then different cleanliness requirements have been applied to spacecraft based on their destination, mission type, and scientific objectives. The Planetary Protection Subcommittee of the NASA Advisory Council has noted that a strategic Research & Technology Development (R&TD) roadmap would be very beneficial to encourage the timely availability of effective tools and methodologies to implement planetary protection requirements. New research avenues in planetary protection for ambitious future exploration missions can best be served by developing an over-arching program that integrates capability-driven developments with mission-driven implementation efforts. This paper analyzes the current status concerning microbial reduction and cleaning methods, recontamination control and bio-barriers, operational analysis methods, and addresses concepts for human exploration. Crosscutting research and support activities are discussed and a rationale for a Strategic Planetary Protection R&TD Roadmap is outlined. Such a roadmap for planetary protection provides a forum for strategic planning and will help to enable the next phases of solar system exploration. 相似文献
93.
张海波 《长沙航空职业技术学院学报》2009,9(3):62-65
运用先进的物资管理理念和新近飞速发展的物流新技术,结合航空修理企业对物资管理的特殊需求,设计了一个基于B/S架构的航修企业物资管理信息系统。 相似文献
94.
The envisaged future space research programmes, whether in the field of space exploration or Earth observation are becoming more and more technically complicated and so costly that a single nation can hardly afford to realize them. Major non-European space-faring nations, China and India will progressively play an important role besides US, Russia and Japan. The Space Advisory Group of the European Commission recommended that the European Commission supports within Horizon 2020 a comprehensive Robotic Mars-Exploration Programme under European leadership that should become an essential element of a coordinated international space research programme. The International Space Station (ISS) experience shows that cooperative space programmes build links between industries and laboratories from around the world, which then further develop in non-space related activities, with positive impact on the economy and scientific research. Strategies need to be developed to mitigate the gradual increasing risks incurred by climate change. In order to lower their entry barrier to engage in space emerging and developing space nations need to be included in cooperative space programmes. We present the recommendations of the Space Advisory Group of the European Commission concerning Europe's participation to global space endeavours. 相似文献
95.
叶颖 《西安航空技术高等专科学校学报》2006,24(5):79-80
投影机在教学中已经得到了广泛应用,但因其价格高、维修费用高、环境要求高、灯泡使用寿命短等问题,已经影响了设备的正常使用。因此正确使用和维护投影设备,以提高投影机的使用寿命,降低使用成本,是广大使用者和管理者必须重视的一项工作。 相似文献
96.
谌勇 《华北航天工业学院学报》2006,16(2):26-28
本文论述了高校收费定价应充分考虑居民收入水平等诸多方面,国家应成为办学的主体。要解决贫困生上大学的学费及生活费问题,就必须抓紧建立全国性个人征信机构,成立国家助学贷款政策性银行。 相似文献
97.
师文明 《郑州航空工业管理学院学报(管理科学版)》2007,25(2):6-9
武汉城市圈虽然城市密集,基础较好,但是城市圈内各城市间没有形成良好的分工合作,产业低水平重复,资源配置效率低下。通过运用计量经济学工具,建立集聚经济的分析框架,测算武汉城市圈内各城市的产业集聚效应,来探讨武汉城市圈建设中的产业政策选择问题。通过分析我们发现,在武汉城市圈中,黄冈市、成宁市和天门市不适合优先发展工业.因此未来要增强自身经济集聚能力,加快经济发展速度,与武汉城市圈整体发展水平相协调;武汉市和仙桃市适合优先发展轻工业;黄石市、鄂州市、孝感市和潜江市适合优先发展重工业。 相似文献
98.
Robert J. Rovetto 《Space Policy》2013,29(4):225-228
The question is: should the United States and nations at large pursue a human spaceflight program (and if so, why)? I offer an unwavering positive answer to this question, and state the reasons for it while considering the broad challenges and benefits of (human) spaceflight. Space exploration is a human activity that is intrinsically forward-looking, and as such, has positive potential. Both national and international space programs can galvanize the population, inspire the youth, foster job-creation, and motivate the existing workforce. The nature of the enterprises involved—their scale, novelty, and complexity—requires a steady and continuous upward progression toward greater societal, scientific and technological development. That is, in order to overcome the challenges of human spaceflight, progress is required. More to the point, the survival of humanity depends on expanding beyond the confines of our planet. Human spaceflight, in short, presents us with an opportunity to significantly advance the nation and the global community. 相似文献
99.
销售政策与产品定价模型 总被引:2,自引:0,他引:2
本文分析探讨了销售政策与定价模型的关系,建立了考虑销售政策的扩展价格模型。尽管不同企业在制定价格政策上存在不同的做法,但本文关于建立价格政策与定价模型数量关系的方法具有普遍指导意义。 相似文献
100.
高层建筑的防火安全对策 总被引:7,自引:0,他引:7
刘城 《沈阳航空工业学院学报》2005,22(6):184-186
针对高层建筑的特点,分析了高层建筑发生火灾的危险性和危害性,对提高高层建筑消防安全需要进行全面系统设计,实施全方位科学运作,加强各方面综合协调,并对防范火灾发生,控制火灾扩大,确保安全疏散等问题进行了探讨。 相似文献