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41.
This paper tests the assertion that experienced contractors are more competitive than inexperienced contractors by measuring the effect of experience on bidding competitiveness for building contracts procured by a regular client. Contractors are grouped into experienced and inexperienced contractors, and two levels of contractors’ experience are identified: (1) bidding experience only and (2) bidding plus construction experience. Results of two-sample t tests show that experienced contractors are more competitive than inexperienced contractors. Contractors’ competitiveness in respect of school contracts and other contracts are further compared in evaluating the relationship between the project type and experience effect. Experienced contractors are, on average, more competitive in competing for school contracts. It emerges that the factor of project type familiarity amplifies the experience effect. A comparison of experienced contractors’ competitiveness in bidding for (1) new building works and (2) alteration and extension works shows that the effect of experience would be more significant when contract works packages are highly standardized. 相似文献
42.
天桥水电站是黄河中游北干上的第一座高泥沙、低水头、大流量的径流式试验电站。它成功的施工与运营经验不仅对在黄河中游北干上开发梯级水电站,而且对中小型径流式水电站的施工都具有重要的借鉴作用。这篇文章总结了两期截流工程、基坑排水、固结灌浆、帷幕灌浆方面的施工经验。在诸如厂房位置的选择以及它的布置,泥沙、冰凌、洪水以及拦污方面的工程设计与运营的宝贵经验,使得水库长期保持高的有效库容和良好的运营状态。特剐是防止进水口淤积和水轮机的磨蚀方面的七条措施是非常有价值的。 相似文献
43.
This study is concerned with the assessment of risk for major construction activities. Risk has been defined as a measure of the probability, the severity, and the exposure of all hazards of an activity. A risk assessor model (RAM) was developed and computerized to determine the risk associated with a particular activity and the justification factor for a proposed remedy. Knowing the value of risk would help contractors identify the high risk of major construction activities and would enable them to allocate safety precautions in a more efficient manner. 相似文献
44.
This paper discusses the need for interface management within construction, with particular reference to building facade interfaces. It categorizes the three different types of interface management—physical, contractual, and organizational. The implication of interface management in construction contracting is discussed; it is explained how the U.K. procurement trends have changed, affecting the interface management within projects. U.K. cladding procurement is very fragmented, and the paper maps the development of a typical cladding system showing the complexities of interface management. Finally, the paper discusses CladdISS, a U.K. government funded research project to develop a standardized strategy for the design and management of window and cladding interfaces. It explains the principles of CladdISS with reference to process maps, action plans, management strategy, bibliography, advice on standards, materials, maintenance, joints, movement, and tolerances. This will enable strategies to be developed to avoid the endemic interface problems occurring on-site. It will also guide the management of the interfaces throughout the project. 相似文献
45.
Various ways of quantifying damages have been applied to productivity loss claims in construction. All of the ways attempt to be as objective as possible based on the extent of information available in a particular case. The measured mile, a widely accepted method, is employed when an unimpacted baseline period of production can be identified. Although that approach is considered to be the most objective method available in such cases, the method is limited and does not directly account for variation in individual productivity values about a normal or natural level of productivity. A gap exists between the use of existing methods and the availability of an appropriate methodology that specifically addresses variation in productivity. The key lies in the way baseline productivity is measured, which is inherently statistical, yet no truly statistical methods are used to establish such a baseline. Using the measured mile as a backdrop, this article provides an objective, measurement-based approach that can be used to establish a productivity baseline applied to construction productivity loss claims, based on the application of statistical methods aided by a process control chart. The focus is on providing the basic principles and concepts underlying the approach presented. 相似文献
46.
Morris Driels John Klegka 《The International Journal of Advanced Manufacturing Technology》1992,7(1):29-37
This article presents a comparative analysis of contemporary printed wiring assembly (PWA) batch manufacturing systems employing
surface mount technology (SMT), This analysis is accomplished by reviewing a typical case study of PWA manufacturing system
in the USA. A previously developed model is then applied to the system to predict the cost and performance in the production
of typical PWA designs. Various modifications to the system are then proposed and evaluated. From the case study, conclusions
concerning optimum manufacturing system configuration for this industry can be drawn and are presented. 相似文献
47.
Tillmann Barbara; Janata Petr; Birk Jeffrey; Bharucha Jamshed J. 《Canadian Metallurgical Quarterly》2003,29(2):470
Harmonic priming studies have shown that a musical context, with its established tonal center, influences target chord processing. This study investigated costs and benefits of priming tonal centers for target processing by adding a baseline condition (sequences without a specific tonal center). Results confirmed harmonic priming, with faster processing for related than for unrelated and less related targets (tonic chord, out-of-key chord, subdominant chord). Comparing targets in baseline contexts with targets in sequences with well-established tonal centers revealed a benefit of processing for related targets but a cost of processing for unrelated and less related targets. Findings are discussed in terms of tonal knowledge activation and suggest that an activated tonal center gives rise to strong expectations for the tonic. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
48.
扣件式钢管脚手架应用代表着建筑工业化的一个重要发展方向 ,如何安全、规范地使用扣件式钢管脚手架将是我们标准化施工的新课题 相似文献
49.
Potential applications of knowledge based expert systems in the area of construction project monitoring and control are described. Originally developed from research in artificial intelligence, these systems are computer programs that can undertake intelligent tasks currently performed by highly skilled people. While some project monitoring can be accomplished by algorithmic procedures, the capability of knowledge based expert systems to deal with illstructured problems and to be extensively modified over time make them desirable for application in this area. Sample applications and heuristic rules in scheduling and inventory control are provided. 相似文献
50.
介绍了长江江新洲堤段应用软体排护岸新型技术的情况,结合长江江新洲护岸工程对软体排施工、工艺、设备作简要叙述。 相似文献