采用局部卸载法测定混凝土坝的应力

采用局部卸载法确定水工建筑物的实际应力时,传感器的灵敏度要与所测定的应变相匹配,其拉压应变范围应大于监测区域的最大应变,要保证传感器状态条件不变.     

A FINITE-DIFFERENCE RELAXATION SCHEME BASED ON BOTH MULTIGRID TECHNIQUES AND HOMOTOPY METHOD FOR 2D STEADY-STATE NAVIER-STOKES EQUATIONS

In this paper, multigrid techniques together with homotopy method are applied to propose a kind of finite-difference relaxation scheme for 2D steady-state Navier-Stokes equations. The proposed numerical scheme can give convergent results for viscous flows with high Reynolds number. As an example, the results of shear-driven cavity flow with high Reynolds number up to 25000 on fine grid 257×257 are given.     

大型水电工程合同方案概述

完成可行性研究后,工程的主要目标如下,这些目标还影响合同方案的选择。 (1)费用最少。不仅要使工程的直接费用达到最小,而且还要使承约费及施工期的利息等间接费和财务费用达到最小。在评估工程有效使用期内的费用时,应综合考虑各种方案的相对指标。这些指标包括出售所增加电力的收入,节省的替代发电费用以及供电所刨的经济效益。     

遥感和GIS在小水电站选址中的应用

运用传统方法在较偏远的地区开展小水电站的选址工作非常困难，而采用遥感和GIS技术则要容易得多。介绍了遥感和GIS技术的适用环境及使用方法。     

宾州大学帕克分校商学院雇员沉默的原因

作为老板的你无意问听到两个雇员的悄悄话，“如果老板知道顾客是这么说的，我这份工作就完蛋了。”你会作何感想？而这正是我在一家知名的高科技公司听到的原话。我们对沟通的研究表明，从基层到高管，各类雇员对言行的“自我审查”（selfcensorship）十分普遍，他们会隐瞒某些信息或想法。     

INVESTIGATION ON FLOW AND HEAT TRANSFER CHARACTERISTICS OF ANNULAR TWO-PHASE FLOW THROUGH THE VENTURITUBE

A model that incorporates the important phenomena in the annular gas-water flow through the Venturi tube is presented. A series of experiments are carried out to measure the flow and heat transfer characteristics in cold and hot conditions. Comparison between numerical and experimental results shows good agreement.     

THE BUBMAC METHOD-A NUMERICAL METHOD BUBBLE DYNAMICS IN VORTEX CORE

This paper presents a numerical method called BUBMAC method,whichis based on the Marker And Cell(MAC) technique,to numerically simulate the problemof bubble dynamics in vortex core. With the incorporation of the azimuthal velocity intothe momentum equation, the model takes into account the complete interaction betweenthe bubble dynamics and the vortex flow field.The three momentum equations (N-Seqs.) are solved numerically by the finite-difference methed, and the motion of bubblesurface is described by tracing massless marker particles distributed only on the surface ofthe bubble. With some important medifications to the original MAC method, the numeri-cal accuracy of the method is conisderably increased. The validation of the proposed BUB-MAC method is checked by comparing the numerical results with some available analyticalsolutions in the cases of spherical bubble evolution and with numerical results in the casesof nonspherical collapse of bubble and bubble evolution in tip-vortex core. The compar-iso     

水是最好的药

人体内有“饥饿疼痛”信号,也有“缺水疼痛”信号。不幸的是,人们把“缺水疼痛”叫做“消化不良”,用各种药物对付它,于是,由脱水引起的新陈代谢紊乱损害了十二指肠或胃的组织。     

观测仪器的设计和安装

现在,观测大体积土体和岩石特性公认的工程方法是使用专门的野外观测仪器.土工工程师为评估工程安全并作出较经济合理的设计越来越重视使用观测仪器.一般仪器(它的应用及相关问题)的概念已在设计和施工中得到广泛的认可.在应用中,所获得的数据量迅速膨胀、硬件激增,加之工业自动化,使大部分专业技术人员的知识显得落后.由于水工工程师对一个成功的观测仪器程序的所有组成部分的理解有限,因此,这些专业技术人员通常需要在大学里进行正规培训.因此,这里所介绍的只是如何缩短现存的知识沟.本文重点集中