Mobility modeling, location tracking, and trajectory prediction inwireless ATM networks

Wireless ATM networks require efficient mobility management to cope with frequent mobile handoff and rerouting of connections. Although much attention has been given in the literature to network architecture design to support wide-area mobility in public ATM networks, little has been done to the important issue of user mobility estimation and prediction to improve the connection reliability and bandwidth efficiency of the underlying system architecture. This paper treats the problem by developing a hierarchical user mobility model that closely represents the movement behavior of a mobile user, and that, when used with appropriate pattern matching and Kalman filtering techniques, yields an accurate location prediction algorithm, HLP, or hierarchical location prediction, which provides necessary information for advance resource reservation and advance optimal route establishment in wireless ATM networks     

火炸药包装用纸桶的研究

简述了我国火炸药包装的现状。介绍了火炸药用纸桶包装的研究情况，其中，较详细叙述了纸桶的力学性能、运输和使用试验结果，分析了纸桶包装火炸药的社会、经济效益。     

铵油炸药在炮孔爆破中的应用

文章介绍了在炮孔直径小于100mm条件下,尤其是光面和预裂爆破中,使用铵油炸药的体会及有关施工工艺.     

机器人离散滑模变结构—PI控制器

本文采用离散滑模变结构控制方法，针对机器人提出了一种滑模变结构——ＰＩ控制方案，给出了该控制方案滑模存在条件及控制器设计方案。该控制器将离散滑模变结构控制和ＰＩ控制两者的优点有机地结合起来，理论分析和仿真结果表明该控制器能使机器人在各种复杂非线性动力学情况下具有良好的性能指标。这种控制器输出切换小，可以投入应用。     

Ni对球墨铸铁热处理的影响

采用电子探针，图象分析仪、差质变分析仪和Ｘ射线衍仪定量研究了Ｎｉ在球铁中的分布和Ｎｉ铸态球铁组成相比例奥氏体中含碳量以及贝氏体转变ＴＴＴ曲线线的影响，结果表明，Ｎｉ在球铁中呈连续负偏析，其加入可以影响球铁组成上比例，并使粤氏体中含碳量和贝氏体转变孕育期期增加。     

A study on the anodic protection of Titanium evaporators in Al2(SO4)3 solution

The feasibility of the anodic protection of titanium evaporators in Al₂(SO₄)₃ solution was studied by the measurement of polarization curves, weight loss, solubility of passive film and AC impedance. The protection parameters and efficiency were determined. In addition, the practical technology of anodic protection was studied by screening reference electrodes and auxiliary cathodes. Throwing power was also measured. Four rows of tube-type evaporators of titanium have been anodically protected in situ. Field tests lasting more than one year show satisfactory results.     

The mixed-type integral equations for transient elastodynamic plane crack problems

In the present paper, by use of the boundary integral equation method and the techniques of Green fundamental solution and singularity analysis, the dynamic infinite plane crack problem is investigated. For the first time, the problem is reduced to solving a system of mixed-typed integral equations in Laplace transform domain. The equations consist of ordinary boundary integral equations along the outer boundary and Cauchy singular integral equations along the crack line. The equations obtained are strictly proved to be equivalent with the dual integral equations obtained by Sih in the special case of dynamic Griffith crack problem. The mixed-type integral equations can be solved by combining the numerical method of singular integral equation with the ordinary boundary element method. Further use the numerical method for Laplace transform, several typical examples are calculated and their dynamic stress intensity factors are obtained. The results show that the method proposed is successful and can be used to solve more complicated problems.     

超微粒乳剂的制备及量子尺寸效应的研究

本文制备了四种不同粒度的超微粒AgBr照相乳剂,用X射线衍射技术对其粒子的大小进行了测定;观察到乳剂的紫外吸收峰随晶体颗粒的减小表现出逐渐蓝移;本文提出晶体表面的悬键的存在使得纳米晶体的平均键能升高,并对纳米AgBr乳剂的量子尺寸效应进行了解释。