通用中小型机械企业网站的需求分析

为了克服中小型机械企业建立网站的经费不足、功能不全和缺乏安全性等问题,提出了建立通用企业网站的方案。首先通过广泛调研企业的需求,总结和分析了企业信息、客户管理、产品管理、销售与市场管理、物资供应管理、人事管理和安全管理等模块的功能;其次,分析了主要的业务流程和业务重组。     

移动基站无线传感器网络2个参数的优化

针对一种移动基站协助数据收集模式,研究移动基站最佳缓冲区位置的设计问题,得出节点在发射半径r=R的情况下,当移动基站缓冲区的中心位于2／3R时,网络的总能量消耗最小,当中心位于1／2R时,网络的寿命最长。在r〈〈R的情况下,节点的发射功率可选择{l..k}中的一种传送数据,并给出通过插值作图法得到最佳基站缓冲区位置的设置与节点最佳发射功率的计算方法,相比采用固定功率发射方法,能够将网络寿命提高5倍。     

形状特征局部操作在实体造型中的实现

文章介绍了实体造型中形状特征的局部操作,研究了包含形状特征描述的数据结构,分析了形状特征的分类、框架、特征间的联系及有关操作,分析了欧拉运算及实现思路,在此基础上对实体造型进行局部操作,提高了造型中的运算效率,也对特征造型作了相应的探讨。     

特种电动机高压阀门准确制动的仿真计算

对于特种异步电动机拖动的高压阀门 ,切断电动机交流供电电源后 ,在电机的定子绕组中通入适当的直流电流 ,产生直流磁场 ,使电机进行能耗制动 ,让阀心和电机转子的能量 ,包括动能消耗在转子的绕组中 ,达到准确停车的目的。介绍了这一过程的计算机仿真计算     

Initial high beta operation of the HBT-EP Tokamak

HBT-EP is a new research tokamak designed and built to investigate passive and active feedback techniques to control MHD instabilities. In particular, HBT-EP will be able to test techniques to control fast MHD instabilities occurring at high Troyon-normalized beta, _N Ba/I_p [Tm/MA], since it is equipped with a thick, close-fitting, and adjustable conducting shell. The major goals of the initial operation of HBT-EP have been the achievement of high beta operation (_N 3) using only ohmic heating and the observation of MHD instabilities. By using a unique fast startup technique, we have successfully achieved these goals. A variety of MHD phenomena were observed during the high beta operation of HBT-EP. At modest beta (_N 2), discharges have been maintained for more than 10 msec, and these discharges exhibit saturated resistive instabilities. When _N approaches 3, major disruptions occur preceded by oscillating, growing precursors. During start-up, one or more minor disruptions are usually observed. A 1-D transport code has been used to simulate the evolution of the current profile, and these early minor instabilities are predicted to be double tearing modes. The simulation also reproduces the observed high beta operation when saturated neo-Alcator energy confinement scaling is assumed.     

亭子口缆机运行效率提高的工作研究

根据缆机浇筑混凝土的工艺特性,将缆机浇筑混凝土过程中的车辆运输及缆机吊运程序进行作业流程分解,将缆机吊运作业周期划分为9个操作单元,采集缆机吊运混凝土过程中卸料和浇筑全周期各单元的50个工作样本数据进行统计分析,找出需改进的关键点,针对性地提出了6项改进措施.改进作业方案后缆机吊运混凝土的效率提高了约20％.     

A private versus a public space: Anonymity and buying decorative symbolic goods for avatars in a virtual world

The virtual world has become a new channel in which people can contact with others, and organizations can provide service to their customers. Selling symbolic virtual goods has also emerged as a new economy in the virtual world. Such symbolic goods cannot facilitate people to accomplish any specific tasks; people buy them simply to decorate their avatars. This study is based on the theories of symbolic consumption, self-presentation, and computer-mediated environment, to investigate why people buy decorative symbolic goods in the virtual world. The results show that people buy symbolic virtual goods for both emotional and social values. While user perceived social presence and telepresence affect both social and emotional value of symbolic goods, individual self-presentation motivation affects only social value. Besides, anonymous users in the virtual world show behaviors that differ with non-anonymous ones.     

汉语同语的功能特点与英译策略

以北大语料库(CCL)为例,分析论述汉语同语的功能特点.除了和英语同语一样可以表示强调以外,它们还具有转折、让步和赞誉的功能.对汉语同语进行英译时,应通过“理解-传递-体现”三个阶段实现功能对等.对表强调功能的单举式同语,可以保留其语言形式;对具有转折、让步和赞誉功能以及表强调功能的对举式同语,则应弃形式、保功能.     

大中型水电站机电工程质量全过程控制的主要措施

水电站机电工程质量控制,对确保按照设计质量要求生产供货、按照规范标准安装试验、确保电站安全稳定运行、提高经济收益有着重要的意义。但是,质量控制是一个系统全面、不断进步的工作,需要我们不断探索,不断进步。     

锅炉过热器/再热器管道热流密度的评估方法

通过建立数值模型进行编程计算,分析了锅炉过热器/再热器管道在不同的管道几何尺寸、烟气温度、蒸汽流量和温度下,各个界面热流密度的变化情况。通过回归分析得到了热流密度与管道内壁侧氧化层厚度和运行时间的关系表达式,即热流密度的评估关系式。