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991.
992.
Large refurbishment projects are characterized by highly varied costs from one project to another. In Finnish underpinning, only retrospective analysis of costs has been available for the owner’s decision process. In order to develop tools for pre‐tender cost estimating and for comparison of different design solutions and evaluation of tenders of the underpinning project, two different cost models have been developed for research. In both models developed, the minimum data required is the pile length. In the more detailed model, the assessment is based on the design solution, including known pile types and the load transfer classification. Both models are easy to use, and the percentage of explained variance is fairly good in the more detailed model. 相似文献
993.
This paper is a case study of the use of multiple linear regression analysis to quantify a claim for extra payment to a subcontractor for work on a substantial construction earth-moving project. The basis of the claim was that the client and main contractor required the work to be executed in ways other than that originally planned by the subcontractor, reducing efficiency and so increasing costs. The authors of this paper represented the earth-moving subcontractor in a legal arbitration, in which this application of multiple linear regression analysis was fundamental to quantifying the amount claimed in the case. The analysis determined the time required to perform earth-moving tasks, based on a set of explanatory variables, using data sets recorded on-site. The same equation was then applied to the plan of work used for the tender and was used to show that the comparative efficiency between tender and actual was as low as 25%. The claim was successful, and the calculations described in this paper were used to quantify a total additional payment of approximately £;380 000. 相似文献
994.
从结构设计角度谈影响工程造价的因素和管理措施 总被引：1，自引：0，他引：1
本文着重分析了结构设计不合理引起的工程造价增加的原因,并提出相应的管理措施。 相似文献
995.
Mei‐Yung Leung Paul Olomolaiye Alice Chong Chloe C. Y. Lam 《Construction Management & Economics》2013,31(9):891-903
Cost estimation not only requires precise technical and analytical input from estimators but also involves the use of subjective judgement. An investigation on the impact of stress on estimation performance was conducted involving 177 professional estimators in Hong Kong. Using correlation analysis, regression analysis and structural equation modelling, the relationships between stress and various aspects of estimation performance are examined and a causal structural model is developed. The results indicate that stress is a cause of negative estimation performance (resulting in weak interpersonal relationships, unfamiliarity with organization and ineffective process), while, simultaneously, it is beneficial to the professional estimation performance. Furthermore, there is an inverted U‐shaped relationship between stress and the organizational relationship. 相似文献
996.
Mei‐Yung Leung Martin Skitmore Yee Shan Chan 《Construction Management & Economics》2013,31(10):1063-1075
Cost estimators play an important role in an organization, as they produce most predictions of probable final construction cost. Since both under‐ and overestimates can be costly, attention should be paid to the estimating tasks. People involved are therefore likely to experience a considerable amount of mental and emotional stress as a result of inaccurate estimation. The types of stress can be divided into objective stress (OS), subjective stress (SS) and emotional exhaustion (EE). The research described in this paper examined the relationships between OS, SS, EE and stressors based on a survey of construction cost estimation personnel. T‐tests, factor analyses, correlation analyses and regression analyses were applied to identify differences between the professional estimators and other personnel, and the types of stress endured. The results indicate that the stress levels of both the professional estimators and other personnel are similar, with OS being significantly higher than SS, which is in turn significantly higher than EE. For professional estimators, increased levels of OS were found to be mainly associated with lack of autonomy and unfair reward and treatment. Increased SS and EE, on the other hand, appeared to be a function of relationship conflict, work underload, lack of feedback, lack of autonomy and unfair reward and treatment. 相似文献
997.
Frank A. Btzkes 《Bautechnik》2010,87(3):145-157
Der Nachweis des gestörten Bauablaufs ist die schwierigste Herausforderung für Baubetriebler. Dies liegt nicht nur an der Komplexität gestörter Bauabläufe großer Projekte, sondern vor allem an den Anforderungen, die Baujuristen an den Nachweis stellen. Disturbed construction process — Determination of extra construction time and calculation of the additional costs of construction. The detection of the disturbed construction process is the most difficult challenge for construction managers. This is not only because of the complexity of disturbed construction processes of large projects, but primarily because of the requirements of demonstration for the legal experts in construction. 相似文献
999.
Iris Panorel Sergei Preis Iakov Kornev Henry Hatakka Marjatta Louhi-Kultanen 《臭氧:科学与工程》2013,35(2):116-124
Oxidation of paracetamol in aqueous solution was studied by using pulsed corona discharge as a means for advanced oxidation. Pulse repetition frequency, the delivered energy dose, and oxidation media were the main parameters evaluated. The pulsed corona discharge treatment appeared to be effective in oxidation of paracetamol: complete degradation of target pollutant together with partial mineralization was achieved at moderate energy consumption; oxidation proceeds faster in alkaline media, the fastest oxidation rate was observed in oxygen-enriched air. Low-molecular carboxylic acids were identified as the products formed in the reaction. 相似文献
1000.
黄水庆 《江汉石油职工大学学报》2009,22(5):66-68
随着市场竞争的加剧,野外施工项目成本管理的难度加大。在成本管理上必须消除\"误区\",建立完善成本风险控制机制,实行全员、全方位和全过程的成本管理,从而,不断增强企业自我发展的后劲,实现\"低成本竞争,高品质管理\"的成本领先战略。 相似文献