Human Mission from Planet Earth: finding a rationale for exploration of the Moon and Mars

This paper advances scenarios for an evolutionary approach to the establishment of a Human Mission from Planet Earth involving exploration and utilization of the Moon and Mars. Of critical importance are the concepts of robotic–human and Moon–Mars synergies. The paper discusses the rationale variables that have an influence on types of space activities pursued and thus the policy that leads to particular scenarios. In this regard, the technological, scientific, and sociopolitical/socioeconomic impacts and consequences related to a Human Mission from Planet Earth are examined.     

Hybrid optimization for multiple-impulse reconfiguration trajectories of satellite formation flying

A hybrid optimization method is developed for fuel-optimal reconfigurations of a group of satellites flying in formation. The genetic algorithm performs a global search to find two-impulse trajectories, and primer vector analysis finds multiple-impulsive local optimal trajectories with the two-impulse trajectories as initial guesses. Hybrid optimization finds globally optimal trajectories for formation reconfigurations, including formation resizing, reassignment and reorientation maneuvers. Multiple-impulse trajectories reduce the fuel consumption from the two-impulse trajectories by up to 4.4% for those maneuvers. In real missions, satellites can follow two-impulse trajectories to gain the advantage of a smaller number of impulses, with the cost of slightly more propellant. The qualitative characteristics of the optimal trajectories are analyzed from the number of optimal trajectories found by hybrid optimization.     

Formation of Giant Planets– An Attempt in Matching Observational Constraints

We present models of giant planet formation, taking into account migration and disk viscous evolution. We show that migration can significantly reduce the formation timescale bringing it in good agreement with typical observed disk lifetimes. We then present a model that produces a planet whose current location, core mass and total mass are comparable with the one of Jupiter. For this model, we calculate the enrichments in volatiles and compare them with the one measured by the Galileo probe. We show that our models can reproduce both the measured atmosphere enrichments and the constraints derived by Guillot et al. (2004), if we assume the accretion of planetesimals with ices/rocks ratio equal to 4, and that a substantial amount of CO₂ was present in vapor phase in the solar nebula, in agreement with ISM measurements.     

卫星用电容器的性能、特点和应用可靠性

介绍星用电容器选用要点、失效实例，以及如何提高固但、液但、陶瓷电容器的应用可靠性。还谈及四个问题：①固钽不能用在电源滤波器中；②因钽的可靠性与使用线路阻抗有关，如果线路阻抗越小则可靠性越差；③液钽易发生振动失效，有些在振动激励下可能成为瞬息电势源（间歇短路）；④多层陶瓷电容器的低压失效。分析了这些特殊失效现象及失效机理，提出可能采用的筛选方法。     

针对不同目标时对接机构适应性研究

讨论了对接过程的动力学模型、与不同质量飞行器对接过程的特点，以纵向性能为例，提出了缓冲性能参数与对接初始条件组合设计，使对接机构能够适应不同对接飞行器质量特性的要求。仿真结果表明，该方法是可行的。     

高超声速边界层的转捩及预测

首先描述了边界层转捩的基本过程及研究内容。在此基础上,指出了高超声速边界层不同于不可压缩边界层的流动不稳定性特性,并介绍了边界层的转捩机理与感受性特征;给出了高超声速三维边界层中预测转捩的常用方法,并着重介绍了多用于工程实际的e N方法以及对e N方法的理性改进,同时列举了在高超声速三维边界层中应用e N方法实现转捩预测的多个实例。最后,分析并总结了高超声速边界层转捩预测所存在的困难及需要解决的问题。     

航天电子产品金属晶须形成机理、危害及抑制措施分析

金属晶须自发生长是材料科学中长期受到关注的科学现象.随着航天电子产品集成度的提高,由金属晶须自发生长引起的短路和电子故障问题对航天电子产品的可靠性构成了潜在的威胁.因此,研究金属晶须的生长规律,分析金属晶须的生长机理,探寻抑制金属晶须生长的技术手段成为当前研究的热点.针对近年来国内外对金属晶须生长现象的一些相关研究进行了分析,主要包括金属晶须的生长行为、各种影响金属晶须生长的因素、解释锡晶须生长机理的理论等.结合航天型号金属晶须生长导致的故障,对晶须危害进行了分析,并提出了金属晶须抑制的常用措施.     

高校教师薪酬激励机制探讨

如何增强薪酬分配的激励性是目前我国高校人事制度改革的重点。通过调查国内不同地区、不同类型的40多所高校有关薪酬与考核制度的信息和资料，深入探讨了我国高校教师薪酬激励状况和薪酬激励机制的特殊性。调查表明，目前我国高校教师的薪酬体系为三元结构，薪酬激励机制普遍采用3P模式。     

分布式小卫星SAR系统GMTI模式构形优化

对分布式小卫星SAR系统地面动目标检测GMTI模式的研究目前正处于广泛探索阶段。如何评价一个分布式卫星系统的GMTI能力，编队构形对GMTI到底有怎样的影响，怎样设计编队使系统GMTI能力最强等问题是文章讨论的内容。从盲速比例的角度出发，提出对系统的GMTI功能进行衡量的定量指标，分析编队构形方式对该指标的具体影响，寻找GMTI模式下可能的编队优化方法。     

Dynamics and Composition of Rings

Planetary rings are found around all four giant planets of our solar system. These collisional and highly flattened disks exhibit a whole wealth of physical processes involving dust grains up to meter-sized boulders. These processes, together with ring composition, can help understand better the formation and evolution of proto-satellite and proto-planetary disks in the early solar system. The present chapter reviews some fundamental aspects of ring dynamics and composition. The forthcoming exploration of the Saturn system by the Cassini mission will bring both high resolution and time-dependent information on Saturn’s rings.