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131.
Road tunnel excavation often traverses coal strata,which is at risk of firedamp explosion that usually results in disaster.Airtight concrete grouting is popularly used in this kind of tunnel project,Based on the essential theory of mechanics of fluids in prous media,the principle of improving concrete airtight property and its influential factors are investigated.The proportioning tests and monitoring method for airtight concrete are introduced,which is illustrated by a case study applied to the project of the Huayinshan Tunnel.It is proved by engineering practices that the achievement of this research work is beneficial to tunneling project across coal strata. 相似文献
132.
A CAD/CAE system of the ring-type planetary reducer with small tooth number difference is presented.It is a parameterized CAD/CAE system adopting the object-oriented technique and comprising in itself the geometric feature database(including the modules of ring-plates with ineer te4eth,eccentric shaft modules and output shaft modules),standard componentdatabase and material database.In cdomparison with design by handwork,this computer aided design and analysis system has the advantages of improved quality,shortened design period and reduced cost.The reliability of the system has been verified by a illustrative example. 相似文献
133.
LIANG Zong-bao CHEN Wei-min FU Yu-mei ZHU Yong HU Shun-ren 《重庆大学学报(英文版)》2006,5(3):131-136
1 Introduction a The statistical process monitoring and quality control in the industry manufacturing using exponentially weighted moving average (EWMA) control chart have attracted much attention recently. Parameter selection is the key to optimal design… 相似文献
134.
应用高压电激法,把载有表达不同杀虫谱晶体蛋白基因的两种质粒同时转入晶体缺陷型的BT菌株,或者把载有表达单一晶体蛋白基因的质粒转入不同亚种且产生晶体的天然BT菌株中,通过生物测定法,快速而简便地筛选出杀虫谱扩大及杀虫毒力提高的重组菌株。所筛选到的菌株产生的伴孢晶体,同时对鳞翅目及双翅目昆虫幼虫有毒杀作用,并且重组菌株所产生的伴孢晶体的形状有异于其出发菌株的伴孢晶体。 相似文献
135.
面向知识管理的国家科研项目文件管理体系:模式分析与模型构建 总被引:1,自引:1,他引:0
136.
137.
郑玲 《重庆大学学报(英文版)》2003,2(2)
1. Introduction As is known, the function of a suspension system is to support an entire vehicle at axles so as to improve ride comfort by vibration absorption. It also provides handling stability in steering and acceleration as well as braking. However, the solution of the design contradiction between ride comfort and handling stability can抰 be achieved by passive suspension system elements. Some active suspension systems have been developed in order to handle the compromise, but they requi… 相似文献
138.
梁宗保 《重庆大学学报(英文版)》2005,4(2):80-83
1 Introduction 1 The safety and security of bridges have come to be a particular concern by engineers and managers in the recent decades. With the great development of traffic and transportation, a number of highway bridges are expected to be monitored automatically in a monitoring center far from the field. But it is difficult to accomplish the remote monitoring process by conventional methods, in which the state information of bridge have to be collected manually and the data processing done… 相似文献
139.
本文初步研究了柑桔潜叶蛾(Phyllocnistis citrella)幼虫寄生蜂(Tetrastichus Phyllocnistoides)和蛹寄生蜂(Cirrospilus quadristriatus)对柑桔潜叶蛾的搜索效应,利用数学模型分析绘制了两种寄生蜂田间搜索效应和寄生蜂种群密度随时间变动三维图。 相似文献
140.
中山大学校园为害树木的白蚁主要是家白蚁,为害树种达24科36种,其受害率达23.3%,有巢率7.2%。 相似文献