以崇尚科学为荣

社会主义荣辱观是科学发展观的重要组成部分,是正确世界观、人生观、价值观、道德观的生动体现。当前,我国正处于改革发展的关键时期,迫切需要建立与社会主义市场经济体制相适应的正确的社会荣辱观,科学的作用正是对这种精神力量的支撑和塑造。     

AATE和ITEP计划下的涡轴发动机分阶段研发综述

为了探索新型航空发动机研制规律,通过收集整理美国AATE和ITEP两项计划中的2237 kW涡轴发动机GE3000和HPW3000研发的一些公开信息,结合美国国防科技的分类分阶段管理,再现了美国新型发动机阶段化研发的全貌.指出美国国防科研的分类管理体现了原始创新和集成创新均衡发展的科技创新理念,国防武器装备研发的分阶段全寿命周期管理反映了基于技术成熟度对复杂系统研发有效的风险管控理念,实力相当的竞争在帮助军方获得最优装备的同时,也促使参与竞标的公司不断提升自身的技术和管理水平,推动了持续的技术创新.     

语言学与语言教学纵横观

多年来语言学研究与语言教学的实践表明,外语教学的良好成就离不开语言学界对于语言共性的深层理解。根据当今语言学的特点和观点,通过语言变体之分析,阐述了语言的体系或结构,指出了语言学的发展趋势以及语言教学的理论依据。     

The Radio Frequency Subsystem and Radio Science on the MESSENGER Mission

The MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) Radio Frequency (RF) Telecommunications Subsystem is used to send commands to the spacecraft, transmit information on the state of the spacecraft and science-related observations, and assist in navigating the spacecraft to and in orbit about Mercury by providing precise observations of the spacecraft’s Doppler velocity and range in the line of sight to Earth. The RF signal is transmitted and received at X-band frequencies (7.2 GHz uplink, 8.4 GHz downlink) by the NASA Deep Space Network. The tracking data from MESSENGER will contribute significantly to achieving the mission’s geophysics objectives. The RF subsystem, as the radio science instrument, will help determine Mercury’s gravitational field and, in conjunction with the Mercury Laser Altimeter instrument, help determine the topography of the planet. Further analysis of the data will improve the knowledge of the planet’s orbital ephemeris and rotation state. The rotational state determination includes refined measurements of the obliquity and forced physical libration, which are necessary to characterize Mercury’s core state.     

平尾均值在武器装备科学技术奖成果评定中的应用

分析、比较了样本均值、截尾均值、平尾均值在统计学意义下的特性和差别,阐述了在武器装备科学技术奖成果评定中,以平尾均值替代样本均值的必要性和意义。     

Applying the mathematical theory of stochastic processes to lunar and planetary science: the ancient oceans on Mars case

The Mathematical Statistics Theory (MST) and the Mathematical Theory of Stochastic Processes (MTSP) are different branches of the more general Mathematical Probability Theory (MPT) that represents different aspects of some physical processes we can analyze using mathematics. Each model of a stochastic process according to the MTSP can provide one or more interpretations in the MST domain. The importance of MTSP is that each such interpretation can provide large amount of new information. While large body of work on the impact crater statistics according to MST has already been done, it is yet to be investigated as to how we can model a stochastic process according to MTSP; for example, bombardment of the planetary surface or something else in a Lunar and Planetary Science (LPS) domain. In order to show possible achievements, the possible existence of a Martian ocean was chosen as a query that could be addressed through computations using presumptions according to MTSP, including probability of existence as well as lateral and vertical extent and duration of time. While the presumptions for this particular case will also be addressed in certain degree, this will be done primarily to show complexities of some physical process that can be modeled, rather than to prove correctness of the concrete values computed here. While this in itself can be the objective in some future work toward the formal proof of the probability, extent, and timing of oceans on Mars, the basic idea here is to show the basic principles of MTSP, and its potential for addressing LPS-related phenomena. Here, I attempt to show how this approach can: (1) provide large amounts of previously unknown information about physical processes on the surface of the planet, (2) lead to a better understanding of the processes that have shaped the surface of the planet, and/or (3) help constrain the amount of resurfacing. Coupled with other current methodologies, MTSP can result in a better understanding of the history of Mars, as well as other lunar and planetary bodies.     

中国探月工程发展及对空间环境与材料研究的需求

文章首先介绍了中国探月工程的发展规划,包括已取得和预期取得的科技成果;随后对我国未来深空探测提出发展设想并进行展望;最后指出探月工程的发展很大程度上受制于对空间环境的认识以及高性能新材料的开发与应用技术,因此必须加强这两方面的研究。     

空间天气科学与有效和平利用空间

空间天气科学是一门新兴的前沿交叉科学。文章首先从发展历程、发展现状和发展态势角度对空间天气科学进行了系统介绍,并指出空间天气科学是经济社会发展的"助推器"、助力科技革命的"加速器"和关系空间安全的"倍增器";接着对空间天气科学与有效和平利用空间的关系进行了阐述;最后对我国空间天气科学的发展和对人类的服务前景进行了展望,并给出了制定和实施"国家空间天气十年计划"和"空间天气科学服务和平利用空间国家专项"建议的初步构想。     

“火星科学实验室”巡航段导航、制导与控制

介绍了美国最近实施的火星着陆任务——"火星科学实验室"在巡航段的姿轨控制和导航系统、巡航轨道控制的约束条件、控制策略设计和执行过程,并对巡航段导航、制导与控制相关经验进行了分析和总结,对于我国即将展开的自主火星探测具有一定的参考价值。可以得到的启示包括:通过蒙特卡洛仿真制定详尽的轨道控制策略,对非引力作用进行精确建模并标定,细化各种故障预案,选择合适的运载火箭入轨瞄准点,并增加海外测控站。     

基于随机路径点模型的Ad hoc网络复杂统计特性

为了采用复杂网络理论指导Ad hoc网络拓扑结构特性研究,首先介绍复杂网络结构统计特性和随机路径点模型,并从理论上分析基于随机路径点模型的Ad hoc网络的度分布和聚类系数.利用仿真试验的方法产生基于随机路径点模型下的Ad hoc网络各种移动场景,得出Ad hoc网络在这些移动场景下的平均最短路径长度、聚类系数和度分布等复杂统计特性.通过分析仿真试验数据回答Ad hoc网络是否具有小世界效应、Ad hoc网络度分布形态如何以及是否具有无标度属性等问题.