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981.
随着我国市场经济的迅猛发展,建筑行业已经成为社会经济的重要支柱之一。在建筑行业高速发展的今天,探讨建筑工程施工质量和安全的管理,可以促进建筑工程施工质量与安全管理水平的提高,有利于建筑行业的健康快速发展。 相似文献
982.
最近这些年,随着国内乃至国际市场的竞争越来越激烈,很多企业面临被淘汰的威胁,为了适应企业发展的需要,纷纷采用联合承包的模式,效果非常显著。本文主要介绍了工程项目联合承包的特点及其运用,并且根据自身的体会,对联合承包在实际施工中的运用提出了几点改进建议。 相似文献
983.
本文以新型给水管材 PP-R 管为例论述了管材的种类、特点,分析了在小区供水工程中的施工安装操作要领及注意事项,为新型管材在县城小区给水中的应用提供了一定的技术指导。 相似文献
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Helen Clare Lingard Keith Townsend Lisa Bradley Kerry Brown 《Construction Management & Economics》2013,31(10):1101-1112
Project‐based construction workers in the Australian construction industry work long and irregular hours and experience higher levels of work‐to‐family conflict and burnout than office‐based workers, giving rise to an interest in alternative work schedules as a means of supporting work–life balance. Alternative work schedules were implemented in four case study construction projects in Australia. Interventions differed between projects, with two implementing a compressed work week, and the others introducing reduced hours schedules (one of which was optional). Data were collected from each case study project, using various combinations of focus groups, surveys, interviews and daily diary collection methods. The results were mixed. The compressed work week appears to have been favourably received where it was introduced. However, waged workers still expressed concerns about the impact on their weekly ‘take‐home’ pay. Attempts to reduce work hours by changing from a six‐ to a five‐day schedule (without extending the length of the working day between Monday and Friday) were less favourably received. Waged workers, in particular, did not favour reduced hours schedules. The results confirm the existence of two distinct labour markets operating in the Australian construction industry and markedly different responses to alternative work schedules, based upon whether workers are waged or salaried. The results clearly show that attempts to improve work–life balance must take the structural characteristics of the industry's labour markets into consideration in the design of interventions. The impact of alternative work schedules is likely to be moderated by institutional working time regimes within the construction industry. 相似文献
989.
Olusegan Oyewale Faniran Jacob Oludoye Oluwoye Dennis Lenard 《Construction Management & Economics》2013,31(6):485-499
This paper examines the relationships between construction planning efforts and construction planning effectiveness. The influence of the project's environment and organizational characteristics of construction firms on planning efforts and planning effectiveness is also investigated. A sample of 26 building projects was studied and the results were analysed using simple correlations. Three factors were found to have a significant effect on improving construction planning effectiveness: increases in planning time prior to commencement of work on site, the extent to which emphasis is placed on the determination of construction methods during construction planning and the frequency of revision of construction plans after commencement of work on site. Significant relationships were also found between project environment variables and organizational characteristics of construction firms and planning efforts and planning effectiveness. Implications of the results are that construction planners should systematically evaluate alternative plans, sufficient time should be allowed for proper planning, thorough reviews are needed whilst work is in progress, the planning effort needs to be relevant to the environmental context of the project and the firm should be appropriately organized. Suggestions are given for future research studies. 相似文献
990.
In this paper, we study the energy decay characteristics of the nozzle at supersonic velocity. We have taken three types of configuration: circular, square and elliptical. The results are compared to the circular exit design. The experimental data are compared in relation to the pressure ratio. The throat area assumed to be constant. The supersonic potential core length of the different orientations is calculated. From the results, we have found that the exit geometry plays an important role in mixing promotion. The core length of a non-circular jet is less intense than a circular jet. The core length of the nozzle is the same in both under and overexpanded case. In addition to that, there is no sign of axis switching due to weak shock. The results are obtained in two different categories, total pressure data and numerical simulation. An empirical relation is used to investigate the core length experimentally. 相似文献