钢结构设计中稳定性分析

稳定性是钢结构设计中的一个重要问题,它的稳定性会直接影响工程的质量和安全。在现代工程史上,有许多因为钢结构失稳而引发的事故,进而造成严重的经济损失和人员伤亡。所以,为了控制工程的质量和安全,预防工程事故的发生,加强钢结构设计中的稳定性是非常必要的。简要分析了钢结构设计中存在的问题,并提出相关建议。     

清水混凝土施工质量控制

探讨了清水混凝土的常见质量缺陷及监控对策，就如何通过控制所用原材料和配合比设计、施工过程的模板选用、浇筑、振捣养护方法和做好产品保护措施来保证清水混凝土的施工质量进行了探讨，以完善清水混凝土施工工艺。     

数据库在施工标准管理中的开发与应用

介绍了建设施工单位在繁杂的技术管理中,如何运用计算机收集、整理各种相关标准、规范和法规等,建立数据库,便于工程技术和企业管理人员浏览、查询、修改、添加和删除等操作,以提高工作效率和工作质量.     

Simultaneous model building and validation with uniform designs of experiments

This article describes an implementation of a particular design of experiment (DoE) plan based upon optimal Latin hypercubes that have certain space-filling and uniformity properties with the goal of maximizing the information gained. The feature emphasized here is the concept of simultaneous model building and model validation plans whose union contains the same properties as the component sets. Two Latin hypercube DoE are constructed simultaneously for use in a meta-modelling context for model building and model validation. The goal is to optimize the uniformity of both sets with respect to space-filling properties of the designs whilst satisfying the key concept that the merged DoE, comprising the union of build and validation sets, has similar space-filling properties. This represents a development of an optimal sampling approach for the first iteration—the initial model building and validation where most information is gained to take the full advantage of parallel computing. A permutation genetic algorithm using several genetic operator strategies is implemented in which fitness evaluation is based upon the Audze-Eglais potential energy function, and an example is presented based upon the well-known six-hump camel back function. The relative efficiency of the strategies and the associated computational aspects are discussed with respect to the quality of the designs obtained. The requirement for such design approaches arises from the need for multiple calls to traditionally expensive system and discipline analyses within iterative multi-disciplinary optimisation frameworks.     

A comparison of official abstracts and enhanced abstracts for patent search

The official abstracts published together with many patent applications are freely available for search, e.g. using patent office websites such as Espacenet or search engines. Some service providers also offer, for a price, their own enhanced abstracts of patent applications. The authors propose a way of making an objective comparison between searching using the official abstracts and using the enhanced abstracts. The advantages offered by enhanced abstracts will be explained and include simple benefits such as saving time in finding the relevant prior art, and more intricate ones such as better suitability for ranking techniques.     

不只是精益——BIM与精益建造

BIM(建筑信息模型)的出现将使建筑业进入新的时代,从管理模式到建造方式都将发生改变,因为BIM不仅体现了精益思想,还将传统的二维工作方式带入三维的工作方式,这一维的提升让技术更人性化,进而使多团队合作间的沟通协调效率得到有效的提升。     

Forms of Collaboration and Project Delivery in Chinese Construction Markets: Probable Emergence of Strategic Alliances and Design/Build

Changes in regulations to allow foreign contractors to qualify as wholly foreign-owned “construction enterprises” came into effect in September 2002 as one of the steps taken by the Chinese government to honor its World Trade Organization commitments. Emerging markets have a significant impact on the strategic planning of contractors; based on an electronic survey covering foreign contractors, clients (foreign investors), and design institutes, the design/build procurement route in conjunction with strategic alliances has been found to enable foreign contractors to enter the Chinese marketplace. The writers present a strengths, weaknesses, opportunities, and threats (SWOT) analysis to inform readers where opportunities for development might be found and to warn of threats to entry. The research also found that mutual trust, synergistic strengths and complementarities, market demand for services, flexibility for both parties, and minimum change of top managers were ranked as the top five critical success factors for strategic alliances between foreign contractors and design institutes. Finally, medium-sized, state-owned, and large-sized design institutes were ranked as the first, second, and third preferences, respectively, for strategic partnering by foreign contractors.     

Alternative Project Delivery Systems: Applications and Legal Limits in Transportation Projects

This paper presents the results of a comprehensive survey of the legal codes of all the 50 states in the United States regarding alternative project delivery systems in transportation projects. In the past decade there has been a surge of legislation allowing state transportation officials much more flexibility regarding the choice of project delivery systems. These delivery systems are usually selected based on a combination of price and quality. Specific delivery systems studied in this paper are Design-Build, Construction Management at Risk, and Public-Private-Partnership. The background and history of the emergence of these new delivery systems are studied in this paper. The research showed that in many states, alternative delivery systems may be allowed but with specific restrictions. For each state, all of these delivery systems have been researched and placed into one of the following distinguishable categories: (1) fully authorized; (2) authorized but needs extra approvals; (3) authorized for a pilot program and/or with some limitations; (4) not authorized. The output of the survey gives valuable snapshots over the status of each delivery system in regards to its legality in different parts of the country as of December 2006. Comparing the results of this survey with the surveys done previously shows that the trend is to allow states more flexibility in the choice of project delivery systems.     

钢结构工程安装的质量控制要点

钢结构在轻工业厂房中的使用越来越多,文章着重介绍了钢结构厂房在制作、安装过程中质量控制和安全控制的环节要点以及控制方法.     

基于MAP-ICC的无线Mesh网络层次路由协议研究

在研究混合路由协议HWMP和低功率自适应层次路由算法LEACH基础上,提出一种基于能量均衡的层次路由算法MAP-ICC（Mesh Access Point Independent Construction of Cluster）。该算法针对无线Mesh网络中的接入层MAP节点进行独立建簇,以MAP节点的能量消耗为依据计算最佳簇首个数,根据最佳簇首个数对覆盖的环形区域内的MAP节点进行分簇,用户节点根据加权公式选择合适的簇首加入。仿真实验结果表明：提出的MAP-ICC独立建簇算法一定程度上增加了网络生存时间,提高了数据报文发送成功率和降低了路由负载。