铁路信号与列车控制系统的面向对象仿真

该文叙述了面向对象技术（OOT）应用于铁路信号与列控系统建模的方法 ，利用面向对象分析（OOA）和面向对象设计（OOD），把信号系统组成实体的属性和操作封装成对象存贮在软件库中，并可利用这些对象评估铁路信号与列控系统。由于OOT的高可复用性、可扩展性和高开发效率，使得仿真系统的开发时间和费用大大节省。     

A Constraint-Based Interactive Train Rescheduling Tool

In this paper, we report the design and implementation of a constraint-based interactive train rescheduling tool, a project in collaboration with the International Institute for Software Technology, United Nations University (UNU/IIST), Macau. We formulate train rescheduling as constraint satisfaction and describe a constraint propagation approach for tackling the problem. Algorithms for timetable verification and train rescheduling are designed under a coherent framework. Formal correctness properties of the rescheduling algorithm are established. We define two optimality criteria for rescheduling that correspond to minimizing the number of station visits affected and passenger delay respectively. Two heuristics are then proposed to speed up and direct the search towards optimal solutions. The feasibility of our proposed algorithms and heuristics are confirmed with experimentation using real-life data.     

Specification Diagrams for Actor Systems

Specification diagrams (SD's) are a novel form of graphical notation for specifying open distributed object systems. The design goal is to define notation for specifying message-passing behavior that is expressive, intuitively understandable, and that has formal semantic underpinnings. The notation generalizes informal notations such as UML's Sequence Diagrams and broadens their applicability to later in the design cycle. Specification diagrams differ from existing actor and process algebra presentations in that they are not executable per se; instead, like logics, they are inherently more biased toward specification. In this paper we rigorously define the language syntax and semantics and give examples that show the expressiveness of the language, how properties of specifications may be asserted diagrammatically, and how it is possible to reason rigorously and modularly about specification diagrams.     

一种进程间异步通信模型的研究

该文给出了在分布式系统下一种基于消息传递与排队技术的进程间异步通信模型,并给出了消息队列的管理方法和消息传递模式,最后提出了用局部按名手址方式来解决进程寻址问题。     

活塞和缸套孔中心线空间位置尺寸链计算

用概率法对柴油机活塞和缸套孔中心线空间位置尺寸链进行了分析并作了计算尝试，进行在理论上判断，给出的公差性合理。     

黄河小浪底水电站尾水岔管水力试验研究

通过模型试验研究，对小浪底水电站原尾水岔管体型进行了修改，减小水力损失，每年可多发千万ｋｗｈ电，年效益达百万余元．     

Robot Dynamic Modeling Using a Power Flow Approach with Application to Biped Locomotion

In this paper, we present a method for robots modeling called bidirectional dynamic modeling. This new method takes into account the gear efficiency and the direction of power transmission in the gears. Epicyclic gearboxes have often different efficiencies in the two directions of power transmission. The characteristics of the chain of transmission must then be taken into consideration in order to describe the dynamic behavior of robots. The two directions of power flow can indeed occur in robot motions. Depending on that direction the dynamic model is different. The bidirectional dynamic modeling is experimentally applied to a bipedal walking robot. Our method exhibits a better accuracy over classical modeling. Moreover, when applied to computed torque control, the bidirectional model increases the tracking performances.     

引信传爆序列优化设计的有效途径

分析了中,大口径榴弹引信传爆序列的结构特征和传爆机理,着重介绍新一代组合火工品改造传统式传爆序列设计中带来的影响,分析了组合式传爆序列的发展前任。     

基于Linux的Beowulf集群的实现

中国科学院等离子体物理研究所是国内从事核聚变研究和托卡马克(Tokamak)实验的主要基地,由于实验研究的需要,有必要建立自己的大型并行计算机系统,进行托卡马克实验的数值模拟等研究课题。文章介绍了在普通PC机上利用Linux操作系统实现基于分布存储结构的Beowul集群系统的方法,同时也介绍了基于消息传递模型(Message Passing Interface,MPI)的并行程序设计方法。     

新型高速列车实时追踪系统

介绍了利用光纤光栅(FBG)波长编码的特点,采用新型分布式FBG传感实现高速列车实时追踪。其主要结构是沿线等间距设置众多具有不同中心波长的FBG传感头,当列车车轮压上传感头时,中心波长发生偏移,偏移的次数就是列车的轴数,所有传感头所计轴数应该相同,如不相同说明有车厢脱节。从车轮到达每个传感头的时间间隔,可计算出列车的运行速度、加速度,如果在整个调度区间有多趟列车,则在调度中心可精确判断每趟列车所在的位置、行进的速度、加速度和每趟列车间的距离。