计算机网络维护的几点探讨     

谢筱惠 《气象研究与应用》2002,23(3):45-47

概述计算机网络故障分析与诊断的原则 ,分别就计算机网络中遇到的网络硬件故障 ,网络配置故障及 NT服务器故障做一些探讨  相似文献   

Fe-C合金扩散型相变的计算机模拟     

李琼  郝兴安  李正文 《矿物岩石》2002,22(1):91-94

以扩散规律和成核－长大机制为基础，论述了Fe-C合金的扩散型相变数学模型的建立，采用计算机模拟技术来研究TTT曲线及合金元素对它的影响。结果表明，模拟曲线与实际曲线吻合良好，且能动态描述合金元素对TTT曲线的影响。钢的TTT曲线在钢的热处理中极为重要，因此相变的计算机模拟具有广阔的应用前景及实际推广价值。  相似文献   

基于H.323协议的独立IP可视电话的设计与实现     

方湘艳  朱荣  李红  段汉文 《武汉大学学报(信息科学版)》2002,27(1):89-93

论述了独立IP可视电话实现的关键技术，介绍了H．323协议的相关内容，并在H．323协议框架的基础上提出了一种可行的独立IP可视电话的设计和实现方案。  相似文献   

Antiplane SH-deformations near a surface rigid foundation above a subsurface rigid circular tunnel   总被引：1，自引：0，他引：1  

V. W. Lee  M. E. Manoogian  S. Chen 《地震工程与工程振动(英文版)》2002,1(1):27-35

The problem on the dynamic response of a rigid embedded foundation in the presence of an underground rigid tunnel and subjected to excitation of incident anti-plane SH waves is analyzed. By using the exact analytical solution for the two-dimensional SH-wave propagation in and around both the surface rigid foundation and subsurface rigid tunnel, those aspects of the resulting ground motions that are of special interest and importance for seismic resistant design in earthquake analyses have been examined. The computed amplitudes of the resulting periodic ground motions display a very complicated wave-interference between the surface foundation and underground tunnel that lead to observed standing wave patterns, together with abrupt changes in the wave amplitudes and large amplification of the incident motions. Supported by: National Science Foundation grant CMS 97-14859  相似文献   

Technique development of PC104 embedded module and its application in the geophysical instrument design   总被引：1，自引：0，他引：1  

滕云田  张炼  王彦  刘晓芹  马延妮 《地震学报(英文版)》2002,15(4):439-446

Introduction Electronic technique has been developing to so large scale integrated and high intelligent that the microprocessor has been the core in the electronic equipment or in the process control system design relying on its strong controlling and computing power, convenience to be application designed and to be programmed. Now the mainstream solutions widely used in the geophysical appliance are the single chip microprocessor (MCS), the digital signal processor (DSP), the common compute…  相似文献   

PC104嵌入式模块技术研究及在地学观测仪器设计中的应用>.   总被引：8，自引：1，他引：8       下载免费PDF全文

滕云田  张炼  王彦  刘晓芹  马延妮 《地震学报》2002,24(4):421-427

简单讨论了当前地学观测仪器设计中普遍使用的各种微处理器，并详细介绍了嵌入式PC104模块的特点和功能，揭示了该模块在观测仪器设计中具有较好的适用性和优点．通过对PC104模块各应用技术的具体研究，实现了PC104模块在磁通门磁力仪、地震数据采集器、GPS定位导航设备的实际应用设计．   相似文献   

计算机视觉测量准二维控制场建设     

余加勇  邹峥嵘  朱建军 《测绘科学》2008,33(4)

准二维控制场建设是建立CCD摄像机数字畸变模型的关键性工作。准二维控制场按CCD摄像机芯片长宽比4:3设计,并以相片纸为介质、以双矩形为图案、以黑白为色调制作了345个均匀分布的控制点。采用单机式积木型电子经纬仪工业测量系统测量准二维控制场的控制点三维坐标,观测值的点位中误差优于±0.15mm。研究结果表明利用准二维控制场建立CCD摄像机的数字畸变模型,其建设费用低、精度高、使用方便。  相似文献   

应用于地质灾害监测的μC/OS-Ⅱ系统     

吴悦  曹修定  胡景山 《中国地质灾害与防治学报》2008,19(3):130-133

由于地质灾害监测现场的环境恶劣,所以对现场监测仪器系统的软硬部件组成提出了极高的要求。在目前的技术发展趋势下,为了提高仪器系统的智能化程度,大量采用了各种嵌入式操作系统。在这些操作系统中,μC/OS-II得到了广泛的应用。μC/OS-II是一个模块化很高的操作系统,可以根据不同的应用选用不同的模块,保证了可以适应不同的需求。在它基础上开发的仪器在软件系统方面都具有良好的可维护性和可扩充性。随着基于μC/OS-II系统的应用越来越多,我们可以仿效软件编程中的模块编程方式,把各种应用组成软、硬结合的混合模块。利用这些模块可以快速开发出大量新的仪器,最终实现仪器设备的标准化。本文阐述了嵌入式μC/OS-II技术,并对嵌入式μC/OS-II技术在地质灾害监测中的应用、发展进行了讨论。  相似文献   

工程设计中电子文档的管理     

魏茜茹 《中国勘察设计》2008,(1):71-72

电子文档是在以计算机为辅助设计手段的工程设计中所产生的设计文件,电子文档有易复制修改和传递的特点,所以在项目设计过程中电子文档的管理和归档显得尤为重要。通过有效的电子文档的管理系统,可减少工程设计的修改,削减设计总成本。  相似文献   

Eddy correlations for water flow in a single fracture with abruptly changing aperture     

Jiazhong Qian  Min Liang  Zhou Chen  Hongbin Zhan 《水文研究》2012,26(22):3369-3377

Fluid flow in single fractures with non‐uniform apertures is an important research subject in many disciplines. The abruptly changing aperture is a special case of such non‐uniformity. This paper simulates water flow in a single fracture with abruptly changing aperture (SF‐ACA) using the Lattice Boltzmann Method (LBM) and the Finite Volume Method (FVM). The flow occurs with the Reynolds number (Re) ranging from 5 to 900 and a ratio of aperture change (E) of 3 (E = D/d, where D and d are the larger and smaller apertures, respectively). For Re values between 5 and 100, both LBM and FVM can successfully simulate the eddy development in the expansion regime of an SF‐ACA. Flow with high Re values (up to 900) is simulated by FVM, which appears to be numerically more stable than LBM for high‐Re flow problems studied here. The flow symmetry in the expansion regime breaks at the Re value between 400 and 500. Our simulation result shows a linear relationship between l₁/d and Re at low Re (5–100) or higher Re (110–900) values, where defined as the length from the location of abrupt expansion to the right edge of the first eddy along the flow direction. If considering the simulation results for the entire simulated range of Re (5–900), the l₁/d–Re relationship is better described by a non‐linear logarithmical function. The l₁/d approaches an asymptotic constant at large Re. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献