“仪表系统接地设计规定”介绍

概述“仪表系统接地设计规定”（2000版）的内容，重点介绍等电位联结的接地方式及其特点。     

Simulation of cup-cone fracture using the cohesive model

The cohesive model is used for the prediction of the crack path during stable crack extension in ductile materials. The problem of crack-path deviation is investigated by means of simulation of crack propagation in a round tensile bar. The respective phenomenon is known as cup-cone fracture. It is shown that the model is able to predict the failure mechanism, which consists of normal fracture in the center and combined normal/shear fracture in the so-called “shear lips” at the specimen’s rim. The damage evolution and crack path predicted by the model are presented. The effect of the normal and shear failure parameters on the crack-deflection point and several aspects of the finite element mesh are discussed.     

方波扫描路径确定声源声功率误差特性分析

改进了矩形测量面方波扫描路径测量声功率的误差模型 ,以单极子、偶极子及四极子声源为例 ,给出了扫描方向、测量面离声源的距离及扫描线的密度的选取对理论误差的分布图形。分析结果表明 :对选定的测量面 ,在扫描线密度小的情况下 ,通过调整声源离测量面的距离 ,可以在声源近处找到一个最优点或较优点 ,使理论误差为零或很小 ;在绝大多数情况下 ,沿测量面长边扫描误差比沿短边扫描小。     

Time-Space Label Switching Protocol (TSL-SP)—A New Paradigm of Network Resource Assignment

In this paper we propose a new protocol called time-space label switching protocol (TSL-SP) in optical burst switching (OBS), and define the terms time-space label (TSL) and time-space routing (TSR). An important concept of response time is introduced in the time label mechanism. The TSL-SP is a new technology that can quickly and efficiently forward data with a label on the optical networks. A two-dimension label switched path (TD-LSP) can be set up, that is maintained and deleted by the TSL-SP. For clearly illuminating the operation principles of the TSL-SP, we propose a new approach of orthogonal time-space coordinates in which the vertical coordinate is the space label and the horizontal coordinate is the time label. The proposed TD-LSP can dramatically reduce the routing failure probability and greatly improve the link network efficiency compared with other signaling protocols. Moreover, we define the time-space label control plane that can achieve the higher efficiency. When the TSL-SP is applied to networks, switching performance can be improved by two orders compared to the switching performance with the conventional OBS signaling protocols. The fundamental goal of TSL-SP is to band the signaling and routing functions together closely. Also, the TSL-SP can reduce the complexity of the network, support automatic service offering, and provide traffic engineering.     

岳飞《满江红》爱国情结的当代审视

岳飞《满江红》词在中国诗歌史上享誉千古,其豪迈壮烈的艺术张力和悲壮的魅力,震撼并感染了无数国人,铸就了一代代中华儿女的爱国情怀。作为爱国诗篇,其爱国情结与忠君理念相伴共生,今天我们对之作当代审视和解读,应突破狭隘的爱国范畴,将其升华为中华复兴的精神动力。     

不甩线圈的多星形移相变极

对于某些槽数和极数比的多星形移相变极电机,提出与前人不同的是在两种极数下均不甩去线圈的绕组方案,使绕组利用率高,且线圈及其联接都较简单.这种绕组方案在一种极数下并联支路略有不平衡,其所引起的电机定子铜耗的增加是极其有限的,不致影响电机的正常运行.     

Fast and accurate pricing of discretely monitored barrier options by numerical path integration

Barrier options are financial derivative contracts that are activated or deactivated according to the crossing of specified barriers by an underlying asset price. Exact models for pricing barrier options assume continuous monitoring of the underlying dynamics, usually a stock price. Barrier options in traded markets, however, nearly always assume less frequent observation, e.g. daily or weekly. These situations require approximate solutions to the pricing problem. We present a new approach to pricing such discretely monitored barrier options that may be applied in many realistic situations. In particular, we study daily monitored up-and-out call options of the European type with a single underlying stock. The approach is based on numerical approximation of the transition probability density associated with the stochastic differential equation describing the stock price dynamics, and provides accurate results in less than one second whenever a contract expires in a year or less. The flexibility of the method permits more complex underlying dynamics than the Black and Scholes paradigm, and its relative simplicity renders it quite easy to implement.     

地面遥控可调弯接头的设计

钻进过程中,为实现定向控制目标,发明了地面遥控可调弯接头,它通过改变钻井液排量来使上、下花键轴在花键筒内上下滑动,由于各花键齿端部形状的特点,这一滑动会导致上、下花键筒之间发生转动,又由于上、下花键筒的转动轴线与它们的外表面不平行,就会使它们之间出现需要的各种弯角,从而在地面就能改变井下弯接头的结构弯角,满足定向控制技术的需要。整个调节过程花费时间很少,因此可节约钻井成本。     

利用射线路径反演层状介质速度的方法

本文根据欧拉方程对于连续层状介质进行了方程推导，得出一个波传播的射线路径公式，利用中 公式导出了ＶＳＰ资料处理中的速度反演公式。     

Real-time accurate hand path tracking and joint trajectory planning for industrial robots (I)

Previously, researchers raised the accuracy for a robot’s hand to track a specified path in Cartesian space mainly through increasing the number of knots on the path and the number of the path’s segments, which results in the heavier online computational burden for the robot controller. Aiming at overcoming this drawback, the authors propose a new kind of real-time accurate hand path tracking and joint trajectory planning method. Through selecting some extra knots on the specified hand path by a certain rule and introducing a sinusoidal function to the joint displacement equation of each segment, this method can greatly raise the path tracking accuracy of robot’s hand and does not change the number of the path’s segments. It also does not increase markedly the computational burden of robot controller. The result of simulation indicates that this method is very effective, and has important value in increasing the application of industrial robots. Foundation item: Foundation of the Robotics Laboratory, Chinese Academy of Sciences (No. RL200002) Biography of the first author: TAN Guan-zheng, Dr., professor, born in Oct. 1962, majoring in artificial intelligence, robotics and automation.