基于CSCW的选煤厂生产调度管理系统

针对选煤厂生产调度的自身特点,以大屯选煤厂生产调度的实际情况为背景,介绍了基于CSCW的选煤生产调度管理系统,并对此系统的安全性和异构为数据库的访问做了阐述。     

多媒体技术应用于AutoCAD教学的问题研究

随着多媒体教育技术飞速发展,教学过程中多媒体技术得到了广泛的应用,本文针对多媒体技术在AutoCAD教学应用中存在的问题进行了分析,通过说明多媒体技术的优点,结合传统的教学方法,不仅可以提高教学质量,还能促进学生的学习兴趣。最后针对存在的问题提出了一些科学的应用多媒体的方式和方法。     

基于WCF的分布式应用开发

本文介绍了Microsoft用于建立和运行面向服务的应用程序的统一框架WCF的系统结构和技术要素,分析了WCF用于分布式开发的优点及项目的多层开发技术,并通过开发具体分布式应用程序来展现基于WCF构架的分布式应用程序的编程步骤与技巧。     

一个农户生态经济系统的分析

对沈阳市桃仙镇荒山子村一个农户生态经济系统进行分析,结果表明：该农户正处于从传统农业向现代农业的过渡阶段,经济效益较好,整体技术水平和生态效益低,后两了该农户的进一步发展,以目前的生产水平,应采取户与户联合,取得规模效益,以当前农业产业化的发展。     

ProxyServer中Cache的管理和使用

使用Ｃａｃｈｅ可以减少Ｂｒｏｗｅｒ的等待时间和降低代理服务器和Ｉｎｔｅｒｎｅｔ的通信量,本文主要介绍了Ｐｒｏｘｙ对Ｃａｃｈｅ管理和使用。     

Polycrystalline diamond MESFETs by Au-mask technology for RF applications

Metal-semiconductor field effect transistors (MESFETs) were fabricated on H-terminated polycrystalline diamond.The DC characteristics of the p-channel MESFET showed a maximum drain current density of 204 mA/mm at a gate-source voltage of 6 V,and a maximum transconductance of 20 mS/mm at a gate-source voltage of 1.5 V.The small signal S-parameters of MESFET with 2 100 m gate width and 2 m gate length were measured.An extrinsic cut-off frequency (fT) of 1.7 GHz and the maximum oscillation frequency (fmax) of 2.5 GHz were obtained,which was the first report on diamond MESFETs with RF characteristics in China.     

Experimental research on air film formation behavior of air cushion belt conveyor with stable load

In this paper, the air film formation behavior of air cushion belt conveyor with stable load is studied. The air cushion field is analyzed by means of theoretical derivation, numerical simulation and experimental research. An intelligent experiment platform is developed. Three dimensional pressure distribution of air film and the air film thickness distribution along the conveyor belt in the width direction are obtained. The experimental result is analyzed by comparing with theoretical calculation and numerical simulation. The numerical and theoretical results are in good agreement with those obtained from experiments. The air film formation behavior pattern of air cushion belt conveyor with stable load is presented. The optimized film thickness and pore distribution are obtained based on the comprehensive energy consumption. This study provides a basis for the optimization design of air cushion belt conveyor.     

Wave–current interaction with a vertical square cylinder at different Reynolds numbers

Railway Engineering Science - Large eddy simulation is performed to study three-dimensional wave–current interaction with a square cylinder at different Reynolds numbers, ranging from 1,000...     

云南某磷肥厂球磨机钢球配比的优化

针对云南某磷肥厂因钢球配比不合理、大球过多而造成的磨矿细度不高,不能很好地适应磷酸生产要求的问题,分析了入磨矿石的粒度组成.根据矿石的粒度组成采用昆明理工大学段希祥教授的精确化装补球方法,提出了一套针对该磷肥厂球磨机的精确化装球方案,同时提出了一个偏大方案和一个偏小方案,并和现厂的装球方案进行对比.针对四种装球方案进行了实验室扩大试验,研究结果表明:最佳装球方案为精确化装球方案,该方案与现厂的装球方案相比,可以使球磨机的生产能力提高14.44%;根据新方案的粒度特性曲线给出了补加钢球的方案,按此方案补加钢球可以使球磨机中的球荷组成始终保持近似于推荐的初装球组成.     

Buckling of carbon fiber composite pyramidal truss core sandwich columns

This paper deals with the theoretical prediction of global buckling loads for carbon fiber composite pyramidal truss core sandwich columns. Different from thin plate structures, transverse shear effect can not be neglected for sandwich structures. In addition, the attributes of the laminated face sheets are considered in the present paper. A zig-zag displacement approximation is made. Based on the principle of minimum potential energy, equilibrium equations and boundary conditions are derived via the variational method. The critical buckling loads under various boundary conditions are presented. In order to validate the reasonableness of the equivalent-core method, the strain energies stored in the actual discrete truss members and the equivalent continuous homogenous core layer are calculated respectively and compared, and a good agreement is obtained. The proposed analytical method is verified by comparing with the published theoretical predictions and experimental results.