浅谈施工阶段的工程造价管理

就施工单位如何把工程造价的发生控制在合理的范围和核定的造价限额以内，从工程承包实行招投标制、缩短工期、重视现场签证和索赔工作等方面进行了阐述，以达到节约投资，提高经济效益目的。     

Preliminary Study in Spatial Data Warehouse of Flood Control and Disaster Mitigation in Yangtze River Basin

1　ＳｐａｔｉａｌＤａｔａＷａｒｅｈｏｕｓｅ1.1　ＦｕｎｃｔｉｏｎｓｏｆＳｐａｔｉａｌＤａｔａＷａｒｅｈｏｕｓｅＩｎｏｒｄｅｒｔｏｍｅｅｔｔｈｅｒｅｑｕｉｒｅｍｅｎｔｔｏｓｐａｔｉａｌｄａｔａ ,ｔｈｅｄａｔａｄｅｒｉｖｅｄｆｒｏｍｄｉｆｆｅｒｅｎｔｓｕｂｊｅｃｔｓａｒｅｇｒｏｕｐｅｄｉｎｕｎｉｆｏｒｍｆｏｒｍａｔｓａｃｃｏｒｄｉｎｇｔｏｔｈｅｔｈｅｍｅｓｔｈａｔｕｓｅｒｓｃａｒｅａｂｏｕｔ.Ｔｈｅｓｐｅｃｉａｌｍｏｄｅｌｓａｒｅｅｓｔａｂｌｉｓｈｅｄｔｏｐｒｏｃｅｓｓｔｈｅｄａｔａｉｎｔｈｅｖｉｅ…     

北京核电站模拟器硬件的功能和特点

本文介绍北京核电站模拟器硬件构成并分析其功能和特点。     

自来水节能阀的设计

系统地论述了自来水节能阀的控制原理和特点 ,提出了设计框架并进行了理论分析和推导计算     

浅谈监理工程师如何抓好施工阶段的投资控制

在多年工程实践的基础上研究、分析了施工阶段投资控制的方法问题。     

压电主动杆位置和增益在随机智能桁架结构振动控制中的优化

对结构物理参数、几何尺寸、作用荷载和控制力同时具有随机性时 ,随机压电智能桁架结构中主动杆的配置位置和闭环控制系统增益进行了优化 ,基于系统最小储存能 ,构建了具有动应力、动位移可靠性约束的主动杆配置和控制增益的优化模型 ;并对结构动力响应的数字特征进行了推导。通过算例 ,验证了该优化配置模型的合理性和有效性 ,获得了若干有意义的结论。     

多站远程无线控制信号系统通信软件的开发

多站远程无线控制系统是以计算机为中心控制 ,用多个信号源作为下位机通过无线模块进行通信 ,文中介绍了通过无线数传模块实现无线通讯以及ActiveX控件的使用方法 ,提出了使系统应用程序更安全可靠 ,效率更高 ,维护更加方便的几种措施。     

Comparative Coreflood Studies for Precipitation and Adsorption Squeeze with PPCA as the Scales Inhibitor

Comparative adsorption and precipitation squeezes carried out on field core materials demonstrate that significant lifetime enhancement is achievable for precipitation squeeze with respect to more conventional adsorption squeeze. Coreflood tests have been carried out under reservoir conditions (135°C) employing a poly-phosphinocarboxylate (PPCA) as the scales inhibitor. Field treatment simulations, carried out starting from coreflood data and considering the characteristics of a North Sea formation taken as the reference, confirmed the higher performance, in term of squeeze lifetime, of the precipitation squeeze with respect to adsorption. The results pointed out the importance of choosing the appropriate formulation once the operative conditions are known, in order to promote the inhibitor precipitation into the formation. Some implications of these results for the optimization of the precipitation squeeze technology for field applications, with particular emphasis to formation damage, are also discussed.     

Robust pole clustering in a good ride quality region of aircraft for matrices with structured uncertainties

This paper presents a general analysis of robust pole clustering in a good ride quality region (GRQR) of aircraft for matrices with structured uncertainties. This region is an intersection of a ring and a horizontal strip, located in the left half-plane, which is a specific non-Ω-transformable region providing good ride quality of aircraft. The paper applies the Rayleigh principle along the norm theory to analyze robust pole clustering within this region since the generalized Lyapunov theory is not valid for non-Ω-transformable regions. Concerned uncertainties are structured/parametric uncertainties, including interval matrices. The results are useful for robust control analysis and design, especially, of robust good ride quality of aircraft, shuttles, vehicles and space station, as well as some industrial systems. An example of the F-16 dynamics for which GRQR is suitable is included to illustrate the results.     

Robot control and parameter estimation with only joint position measurements

Most adaptive control schemes for rigid robots assume velocities measurements to be available. Although it is possible to measure velocities by using tachometers, this increases costs and the signals delivered may be contaminated with noise. Since the use of encoders allows to read joint position pretty accurately, it is desirable to estimate joint velocities through an observer. This paper presents an adaptive scheme designed in conjunction with a linear observer. Boundedness of the estimated parameters and uniform ultimate boundedness for the tracking and observation errors are guaranteed. Experimental results are included to support the developed theory.