The use of solutions to problems of spacecraft trajectory optimization in impulse formulation when solving the problems of optimal control of trajectories of a spacecraft with limited thrust engine: I

In this first part of our paper, it is suggested to use solutions to boundary value problems in the optimization problems (in impulse formulation) for spacecraft trajectories in order to obtain the initial approximation, when boundary value problems of the maximum principle are solved numerically by the shooting method. The technique suggested is applied to the problems of optimal control over motion of the center of mass of a spacecraft controlled by the thrust vector of jet engine with limited thrust in an arbitrary gravitational field in a vacuum. The method is based on a modified (in comparison to the classic scheme) shooting method computation together with the method of continuation along a parameter (maximum reactive acceleration, initial thrust-to-weight ratio, or any other parameter equivalent to them). This technique allows one to obtain the initial approximation with a high precision, and it is applicable to a wide range of optimal control problems solved using the maximum principle, if the impulse formulation makes sense for these problems.     

方块脉冲函数应用于线性时变系统最优控制的动态规划解法及其改进

本将方块脉冲函数应用于线性时变系统最优控制问题。首先将该问题转化成多段动态规划表示形成，通过求解多段动态规划问题，可得原问题的分段常值解。进而，根据最优控制的存在条件下及对边界条件的进一步处理，导出了原问题更为简明的动态规划表示，使求解结果更为简洁，明潦。与献（１），（２），（３）中的求解方法比较，得到的递推算法简单，便于计算机求解，且不必求解ｍ个２ｎ×２ｎ阶逆矩阵，使计算量及存贮空间大为减少     

目前学籍管理中存在的问题及解决办法

文章就教务管理过程中学生学籍管理、成绩管理等方面存在的问题，提出了相应的解决办法，对教务管理工作的进一步规范化有较大的参考价值。     

The method of nearby problems for estimation of numerical error in orbital-mechanics simulations

The method of nearby problems has previously been applied to validate the accuracy of numerical solutions of the problems in fluid dynamics. In this paper, the application of this method is extended to the problems in orbital mechanics. Using this method, the error in the numerical simulations of two-body and three-body equations of motion is estimated. A fixed step-size and a variable step-size numerical integration scheme are used for the simulations. The method of nearby problems is found to provide reliable error estimates and has advantages of cost efficiency and ease of use.     

Satellite technology and the control of environmental diseases

Health problems, especially those linked to endemic and environmental diseases are among most serious problems facing humankind. Space technology, particularly satellite remote sensing, should be included in the efforts to solve health problems on the Earth, in addition to its current use for remote communications.     

喷管后段内壁铣槽加工工艺

归纳了喷管后段内壁在铣槽加工中容易出现的问题,从技术上进行了分析,结合机床特点,介绍了采取的一系列措施,重点阐述了解决问题的方法和注意事项。解决了长期困扰在生产中的难题,大副降低了加工中的误差幅度。     

高等数学教学中数学建模思想的渗透

本文从数学建模及其重要意义角度出发,指出了学习数学建模的必要性和现在数学教学中存在的主要问题。学习高等数学的目的在于应用数学思想方法解决实际问题,将数学建模思想渗透到高等数学课程中,可提高学生应用数学知识和方法解决实际问题的能力,培养学生的数学素养、创新意识、创新精神和能力,从教学内容、教学手段、评价方法等各个环节注重数学建模思想的渗透,使数学建模意识成为学生思考问题的方法和习惯。     

月球探测中通信跟踪(C&T)技术遇到的新问题

以技术成熟的GEO以下近地轨道的C&T技术为参照点,提出月球探测遇到的新问题———长时间、远距离地月转移轨道测量、环月轨道段测量和月面登陆段测量中的新问题,给出解决这些问题的合理方法。     

火星大气进入段纵向可达区生成的解析同伦法

针对火星大气进入段飞行器的飞行能力分析问题,提出一种基于解析同伦法的纵向可达区(开伞点高度-航程剖面)计算方法。该方法首先分别为最大航程问题/最小航程问题和最大/小开伞高度问题构造最优解已知的初始辅助优化问题,并以此为出发点最终求取原最优问题的解。在求解4个子优化问题的基础上,通过构造合适的同伦参数延拓出纵向可达区。〖JP2〗仿真结果表明,该方法有效避免了最优问题协态初值猜测困难的问题,通过设计合适的同伦参数,可以快速求取任意初始路径角下的开伞点最大/最小航程、最大开伞高度以及纵向可达区。     

目前我省在节能建筑发展中存在的问题与对策探讨

针对我省节能建筑发展的现状以及所存在的问题，本文详细地分析了问题产生的原因，并提出相应的解决这些问题的对策。     

总结经验加强遥测的故障诊断作用

总结多年参加卫星、火箭、导弹靶场试验的经验，特别是９０ 年代多次参加事故诊断的经验，发现在安排测量参数方面存在许多问题；过去，对遥测系统可靠性注意不够；处理数据的时间过长，矛盾十分尖锐，但又没有解决问题的办法。产生这些问题的关键是没有立足于出故障后如何进行结果分析来考虑问题。从实际出发，较为细致地提出各方面存在的问题以及建设性解决问题的办法，供有关领导和同志们参考     

高校青年教师思想道德建设刍议

通过对当前高校青年教师思想道德现状的分析,在肯定青年教师积极、健康、向上主流的同时,指出了存在的三个方面的问题,进而从社会大环境、学校小环境和青年教师自身三个方面深入研究了青年教师思想道德“衰微”的成因。在此基础上,探讨了加强和改进高校青年教师思想道德建设的思路和对策。     

A Proposal for Constructing a Group of Space Objects for Solving Transport and Energy Problems

We propose to develop a scheme for a group of space objects which includes a set of orbital tethers and exchange masses. These objects are injected into circumterrestrial orbits. A variety of problems can be solved with the help of this space system, namely, transport problems and problems of converting the electric power generated onboard spacecraft into mechanical energy of motion of the space objects. In the future, natural celestial bodies (in particular, the Moon) can be considered as elements of the system. This opens up the possibility of using the energy of motion of the Moon both for solving transport problems and for generating electric power onboard spacecraft.     

载人飞船舱内盲区电装操作方法

文章提出了载人飞船电装总装过程中遇到的盲区操作的问题,并根据作者多年的工作经验总结出了初步解决方法,特别介绍了工业视频内窥镜在航天器盲区总装电装工作中的应用背景和应用情况。     

空间容错计算机的基本问题和对策

本文从分折空间应用环境对计算机的要求入手，指出研制这类系统所遇到的主要问题，提出解决这些问题的基本技术和措施。     

基于5M1E的航天器AIT过程共性质量问题管理

文章利用“5M1E”过程管理方法,采取“由下至上”与“由上至下”相结合的识别模式对航天器产品AIT过程共性质量问题进行分析,建立统筹解决、分级治理以及成果固化的工作机制对共性质量问题进行治理。利用这些综合方法对过冷器水堵问题开展了系统治理,取得了很好的效果,证明了5MIE方法对于加强共性质量问题管理的有效性。     

浅析有限责任公司股东优先购买权法律制度的健全

本文针对我国有限责任公司股东优先购买权在实践中常见问题的列举和分析,从不同角度提出作者的观点,对具体问题的解决思路提出立法建议,旨在为解决实际问题提供有效的方案,对公司法律制度的完善有所帮助。     

单纯形法原理及其扩展

详细阐述单纯形法的基本原理,并就使用单纯形法过程中经常遇到的如何寻找初始基本可行解,如何减少单纯形法的计算量以及如何将大规模复杂问题分解成若干个规模较小的简单问题等方面给予简答。     

对《离散数学》中三个公式、定义及定理的研究

本文对《离散数学》中三个公式、定义及定理进行了充分的研究及透彻的分析，分别给出了这三个公式、定义及定理的简化形式及其规律，使得它们变的浅显易懂。而这些无论对老师还是对学生都是十分重要的。     

The Solution of Some Problems of Optimizing the Processes of a Flexible Correction of Motion of Satellite Systems: II.

In a previous paper [1], as a result of group-theoretic decomposition, one of the problems of the optimization of the flexible correction process was reduced to a series of subproblems. In this paper, the analytical solutions to these subproblems are obtained by the sweep method. A series of other similar problems with different variants of flexibility is also considered; the decomposition of these problems is performed, and their analytical solutions are presented. It is shown for some numerical examples that flexible corrections require essentially lower fuel consumption than the rigid correction, where all parameters characterizing the absolute motion of a satellite system are corrected to their nominal values.