32种点群

在固体物理教学中，学生们经常提出，为什么晶体分为７个晶系，１４种布喇菲格子，３２种点群２３０种空间群。本文利用浅显方法，阐述了３２种点群的有关问题。     

Equivalent sample theory of networked control systems and its application

The equivalent sample theory and its application in analysis of networked control system （NCS） are presented. After analyzing NCS＇s scheduling in master-slave mode, the characteristics of time delay and sample are summarized. Looking on master station visiting the slave station as a special sample process, the theory of equivalent sample is presented. And based on it, the stability of a kind of NCS is analyzed. The criterion to determine the upper bound of transmission delay is introduced, which guarantees the stability. Finally, an example with simulation shows the availability and usability of this analysis method.     

Design and realization of a novel multitask TT&C operation pattern

With the sharp increase of China＇s in-orbit spacecraft and the constraint TT＆C resources, a mathematical model for optimal TT＆C resource allocation is proposed, and the TT＆C facility remote monitoring function is designed to achieve the multitask operation pattern under the unified management of the network management center. With this pattern, the TT＆C network management and the spacecraft management are separated, which is quite different from the previous pattern. Further, a novel spacecraft TT＆C technique based on spacecraft control language is developed, and the telecommanding pattern is designed to address the spacecraft operation problems. The engineering application shows that this pattern fundamentally improves the TT＆C network capability, increases the resource efficiency, and satisfies the efficient, accurate, and flexible operation of spacecraft.     

Research on the self-defence electronic jamming decision-makingbased on the discrete dynamic Bayesian network

The manner and conditions of running the decision-making system with self-defense electronic jamming are given. After proposing the scenario of applying discrete dynamic Bayesian network to the decision making with self-defense electronic jamming, a decision-making model with self-defense electronic jamming based on the discrete dynamic Bayesian network is established. Then jamming decision inferences by the aid of the algorithm of discrete dynamic Bayesian network are carried on. The simulating result shows that this method is able to synthesize different targets which are not predominant. In this way, various features at the same time, as well as the same feature appearing at different time complement mutually; in addition, the accuracy and reliability of electronic jamming decision making are enhanced significantly.     

Novel load balancing DHT scheme for the heterogeneous system

The capacities of the nodes in the peer-to-peer system are strongly heterogeneous, hence one can benefit from distributing the load, based on the capacity of the nodes. At first a model is discussed to evaluate the load balancing of the heterogeneous system, and then a novel load balancing scheme is proposed based on the concept of logical servers and the randomized binary tree, and theoretical guarantees are given. Finally, the feasibility of the scheme using extensive simulations is proven.     

Bernstein算子导数与光滑模的等价关系

利用Ditzian模w^2λψλ（f,t)(0≤λ≤1)研究了Bernstein算子导数与它所逼近函数光滑性之间的关系，得到了Bernstein算子导数与Ditzian模的等价定理。     

斜磁场作用下三角形量子阱中的混沌

建立了两个新的低维量子系统模型－斜磁场作用下的直三角和等腰三角量子阱中电子运动模型，借助如莱截面方法对此模型进行了数值计算，数值结果表明在一定的磁场倾斜范围内存在着混沌，并通过此模型讨论了与对称性的关系。     

络合平衡的计算机图解处理

将计算机的数值方法与浓度对数图解法结合，建立和筛选了处理络合平衡的有关数学模型．用Turbo C语言在中平台下．编制了处理络合平衡问题的软件，实现了用计算机图解处理络合平衡问题，既可以准确快速地进行计算，又可以辅之以形象、生动的图形。     

关于S^n＋1中极小等参超曲面的注记

单位球面S^n 1中的等参极小超曲面仅是1-型的或2-型的。从而Bryant猜测的答案是否定的。     

斜角坐标系与周角坐标系组合构图形式研究

从理论上探讨了斜角坐标系与周角坐标系量化图形的组合形式，并详细阐述了两种坐标系的构图方法，从而为此类组合图形的实际应用提供了理论依据。