地球静止轨道空间碎片的处置

介绍了国际机构间碎片协调委员会提出的关于地球静止轨道（GEO）空间碎片问题的研究结果和碎片处置的建议，主要内容包括：GEO与GEO环的概念、EGO上物体现状，EGO空间碎片处置的基本原则和8条具体处置措施建议。该建议已于2000年2月提交联合国和平利用外层空间委员会科技小组委员会第37届会议。     

Cost Engineering – The new paradigm for space launch vehicle design

The paper describes the basic definition and application of 'Cost Engineering' which means to design a vehicle system for minimum development cost and/or for minimum operations cost. This is important now and for the future since space transportation has become primarily a commercial business in contrast to the past where it has been mainly a subject of military power and national prestige. Several examples are presented for minimum-cost space launch vehicle configurations, such as increasing vehicle size and/or the use of less efficient rocket engines in order to reduce development and operations cost. Further a cost comparison is presented on single-stage (SSTO)-vehicles vs. two-stage launchers which shows that SSTOs have lower development and operations cost although they are larger, respectively have a higher lift-off mass than two-stage vehicles with the same performance. The design of a space tourism-dedicated launch vehicle is an extreme challenge for a cost-engineered vehicle design in order to achieve cost per seat not higher than $50,000. Finally an outlook is presented on the different options for manned Earth-to-Moon transportation modes and vehicles – another most important application of 'cost engineering', taking into account the large cost of such a future venture.     

基于双相关峰检测的C/A码伪距精密估计

采用软件无线电技术和数字信号处理技术，直接对A／D变换后的中频信号进行处理，并得到C／A码的相关曲线。利用曲线拟合方法对相关峰波形进行拟合，进一步确定相关曲线的峰值点位置。同时基于双相关峰检测的伪距估计方法，精确求解C／A码伪距观测值。利用自编的仿真程序包，在Matlab中进行了相应的模拟计算。仿真结果表明当信噪比大于26dB时，可得到毫米数量级的伪距估计精度，能够满足GPS模拟源系统高精度自校的要求。     

CCSDS邻近空间链路协议的初步探究

介绍了空间数据系统咨询委员会(CCSDS)制定的邻近空间链路协议的产生背景及发展现状。     

Space commercialization: Lessons from history

Private enterprise seeks to undertake virtually any activity that is institutionally and technologically feasible and that promises a high return on investment. Commercial activities in space would seem to be no exception. Indeed, it is reasonable to expect that, at some future date, commercial activities in space will overshadow government-sponsored research and military activities combined. But this date remains well into the future, it is highly uncertain, and it depends on government policies. Two major factors inhibiting further space commercialization are the current lack of necessary infrastructure and the lack of viable commercial activities. The necessary infrastructure is developing with the increasing operational status of the Space Shuttle and plans for a space station. It remains, however, to place increasing emphasis on the conduct of research in space to identify valid commercial uses of space.     

Searching for the magic bullet

A powerful statistical tool, paired-comparison, was tested as a method to determine the relative value American people place on two possibly competing paradigms in the United States Space Program: “Space as a Place to Explore” and “Civil and Commercial Uses of Space”. A limitation of the results, but not the methodology, is the participants were college students, not “voting” adults. Reliability and validity of items were developed and tested in two studies suggesting that the paired-comparison method is a reliable and powerful tool for measuring the relative value the public may place on programs within the US Space Program.     

中国空间碎片研究的进展

首先对"十五"期间中国在空间碎片研究领域取得的主要进展进行了综述,涉及空间碎片监测预警、航天器防护和空间碎片减缓三个方面;然后对"十一五"期间中国空间碎片研究的主要内容进行了介绍。     

Use of Optical Characteristics to Identify Orbiting Material

Knowledge of the observable properties of orbital debris is necessary to validate debris models for both the low Earth orbit (LEO) and the geosynchronous Earth orbit (GEO). Current methods determine the size and mass of orbital debris based on knowledge or assumption of the material type of the piece. Improvement in the knowledge of material is the goal of the research described herein. The process of using spectral absorption features to determine the material type is explored. A review of the optical measurements of orbital debris as well as current research in the area is discussed. Reflectances of common spacecraft materials are compared. The need for, and advances made possible by obtaining real data are explored. The prospects of the venture are investigated.     

Arms control and disarmament in space: the rough road to Vienna 1984 : Part II

This article continues a detailed examination of the international legal and diplomatic questions relating to arms control and disarmament, focusing on space-based activities. These are importantly concerned with the development of anti-satellite (ASAT) systems and ballistic missile defence (BMD). This part of the article considers the US Presidential-Congressional dialogue - particularly the ASAT testing issue - and Presidential initiatives vis-à-vis the USSR. An epilogue to the original paper considers the diplomatic moves and policy shifts which contributed to the January 1985 US-Soviet meeting and the agreement to begin bilateral negotiations to consider space and nuclear arms.