A selective space strategy for small countries

This article analyses the patterns and trends of small countries' participation in various forms of international space cooperation. The background to formulating a national space programme is discussed, together with considerations in linking national needs, stage of development, resources and capacity with those of the international community. The need for a selective national strategy on space activities is demonstrated: efforts must be concentrated around a few reasonably selected goals, provisions for acquiring information must be maintained, and the space programme must prepare the country for rapid development in all other fields of space research and applications, if world trends require. A brief examination of Bulgaria's space activity is made. A series of advanced space investigations have been undertaken in that country, and space technology transfer and spin-offs have resulted, with valuable benefits for the society and the economy.     

US—Soviet intergovernmental agreement on cooperative space activities : Should it be re-established?

Both political and scientific motives are involved in the possible re-establishment of the US-Soviet Intergovernmental Agreement on Space Cooperation. This article outlines the policy concerns which would have to be addressed in considering a new agreement, from issues of technology transfer and actual scientific benefits, to US political influence on Soviet policies. Some guidelines are offered for future cooperation, on the basis of past experience, and possible long-range cooperative projects are suggested.     

人民币汇率的决定基础与政策配合

作者对导致人民币升值的因素和升值的正负面经济效应进行了分析 ,并提出了减轻负效应的政策建议。     

构建我国石化企业核心竞争力的路径选择

加入WTO后，我国石化企业面临严峻的挑战。应加强核心竞争力战略研究，在国际竞争中培养成长能力，提升价值能力，发展独有技术。在战略重组和竞争合作中，转变发展方式，发挥优势，调整结构，缔造石化企业持续竞争优势。     

MOTION PLANNING OF MULTIPLE MOBILE ROBOTS COOPERATIVELY TRANSPORTING A COMMON OBJECT

Many applications above the capability of a single robot need the cooperation of multipl emobile robots, but effective cooperation is hard to achieve. In this paper, a master-slave method is proposed to control the motions of multiple mobile robots that cooperatively transport a common object from a start point to a goal point. A noholonomic kinematic model to constrain the motions of multiple mobile robots is built in order to achieve cooperative motions of them, and a “Dynamic Coordinator“ strategy is used to deal with the collision-avoidance of the master robot and slave robot individually. Simulation results show the robustness and effectiveness of the method.     

考虑协同航路规划的多无人机任务分配

针对多无人机任务分配与协同航路规划问题，以分布式合同网拍卖算法为基础，构建无人机集群任务拍卖架构与拍卖收益函数，结合模拟退火算法协调任务执行次序，采用A^*算法完成两任务点间航程预估，在任务分配阶段同步完成多无人机间协同航路的初规划，确定最佳任务执行次序，实现任务分配与协同航路规划的紧耦合。仿真结果表明，在考虑禁飞区、障碍威胁情况下，该算法能够有效完成多架无人机不同类型任务的分配，且目标分配、执行次序合理，总执行代价小，各机间负载均衡；在任务分配阶段考虑协同航路规划具有明显的效果，能够有效提高任务分配的合理性。     

T cell regulation in microgravity – The current knowledge from in vitro experiments conducted in space,parabolic flights and ground-based facilities

Dating back to the Apollo and Skylab missions, it has been reported that astronauts suffered from bacterial and viral infections during space flight or after returning to Earth. Blood analyses revealed strongly reduced capability of human lymphocytes to become active upon mitogenic stimulation. Since then, a large number of in vitro studies on human immune cells have been conducted in space, in parabolic flights, and in ground-based facilities. It became obvious that microgravity affects cell morphology and important cellular functions. Observed changes include cell proliferation, the cytoskeleton, signal transduction and gene expression. This review gives an overview of the current knowledge of T cell regulation under altered gravity conditions obtained by in vitro studies with special emphasis on the cell culture conditions used. We propose that future in vitro experiments should follow rigorous standardized cell culture conditions, which allows better comparison of the results obtained in different flight- and ground-based experiment platforms.     

基于态势感知一致性的UAV集群分布式协同性能分析

针对现有无人机集群分布式协同方法没有细致考虑态势感知过程，忽略了对抗环境下态势信息的不确定性对集群协同的影响，对协同性能缺乏量化分析等问题，提出基于态势感知一致性的无人机集群分布式协同方法，并分析协同性能。从集群协同作战角度分析协同方法的实质，考虑态势信息不确定性，给出集群态势感知一致性分析，建立态势觉察一致性、态势理解一致性等概念，并设计协同方法；建立协同时间、协同信息量等指标，分析指标特性，量化分析协同性能；在给定的仿真场景下，对比分析各协同方法性能。结果表明，所提方法协同性能较好，更切合对抗环境，对集群协同作战研究有一定的积极意义。     

Activities of the COSPAR Panel on Exploration supporting the Global Exploration Roadmap

The Global Exploration Roadmap (GER) is driven by several goals and objectives that include space science, the search for life as well as preparatory science activities to enable human space exploration. The Committee on Space Research (COSPAR), through its Commissions and Panels provides an international forum that supports and promotes space exploration worldwide. COSPAR's Panel on Exploration (PEX) investigates a stepwise approach of preparatory research on Earth and in Low Earth Orbit (LEO) to facilitate a future global space exploration program. We summarize recent activities and workshops of PEX in support of the GER.     

Toward a global space exploration program: A stepping stone approach

In response to the growing importance of space exploration in future planning, the Committee on Space Research (COSPAR) Panel on Exploration (PEX) was chartered to provide independent scientific advice to support the development of exploration programs and to safeguard the potential scientific assets of solar system objects. In this report, PEX elaborates a stepwise approach to achieve a new level of space cooperation that can help develop world-wide capabilities in space science and exploration and support a transition that will lead to a global space exploration program. The proposed stepping stones are intended to transcend cross-cultural barriers, leading to the development of technical interfaces and shared legal frameworks and fostering coordination and cooperation on a broad front. Input for this report was drawn from expertise provided by COSPAR Associates within the international community and via the contacts they maintain in various scientific entities. The report provides a summary and synthesis of science roadmaps and recommendations for planetary exploration produced by many national and international working groups, aiming to encourage and exploit synergies among similar programs. While science and technology represent the core and, often, the drivers for space exploration, several other disciplines and their stakeholders (Earth science, space law, and others) should be more robustly interlinked and involved than they have been to date. The report argues that a shared vision is crucial to this linkage, and to providing a direction that enables new countries and stakeholders to join and engage in the overall space exploration effort. Building a basic space technology capacity within a wider range of countries, ensuring new actors in space act responsibly, and increasing public awareness and engagement are concrete steps that can provide a broader interest in space exploration, worldwide, and build a solid basis for program sustainability. By engaging developing countries and emerging space nations in an international space exploration program, it will be possible to create a critical bottom-up support structure to support program continuity in the development and execution of future global space exploration frameworks. With a focus on stepping stones, COSPAR can support a global space exploration program that stimulates scientists in current and emerging spacefaring nations, and that will invite those in developing countries to participate—pursuing research aimed at answering outstanding questions about the origins and evolution of our solar system and life on Earth (and possibly elsewhere). COSPAR, in cooperation with national and international science foundations and space-related organizations, will advocate this stepping stone approach to enhance future cooperative space exploration efforts.