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101.
Liu Shu‐Shun 《Construction Management & Economics》2013,31(9):857-869
Analysing a schedule is beneficial to help stakeholders understand the scheduled project. Project schedules, which create time plans based on the critical path method (CPM) or on resource‐constrained project scheduling problem (RCPSP) optimization, are targets herein. The Theory of Constraints (TOC) treats a schedule as a system. Schedule elements are suspected constraints and a goal depends on the schedule creation policy. Resource information is further surveyed herein to identify true constraints. A framework is proposed to integrate identified constraints on a schedule, and the critical resource chain concept is introduced. Three scenarios illustrate the proposed framework under different scheduling considerations. Results explain schedule constraints, and several schedule analysis issues are discussed. 相似文献
102.
103.
《Structure and Infrastructure Engineering》2013,9(11):1486-1498
AbstractThe cables in a cable-stayed bridge are critical components supporting the long-span girders and ensuring their functionality. However, cables are prone to fatigue damage and atmospheric corrosion, which directly affect the bridge safety. This study presents a framework for system reliability evaluation of in-service cable-stayed bridges subjected to cable degradation. The effect of cable strength degradation on the system reliability is demonstrated through simulation on a parallel-series system representation. Learning machines are utilised to approximate the non-linear and dynamic response functions of critical components due to cable rupture, and the system reliability is finally evaluated from the event tree established by the β-unzipping method. Both short-span and long-span cable-stayed bridges are selected as prototypes to investigate the influence of cable degradation on the system reliability. On this basis it is revealed that cable degradation can significantly influence the collapse mechanism of a cable-stayed bridge and thereby lead to a significant reduction in the system reliability. This phenomenon is associated with cable spacing, where a spare cable system seems more sensitive to cable gradation. It is demonstrated that the consideration of cable corrosion and correlation is essential for lifetime safety evaluation of in-service cable-stayed bridges. 相似文献
104.
现阶段,城市产业转型已经成为资源型城市发展的热点与难点问题。本文以安徽省煤炭资源型城市淮北市为例,通过分析其三次产业发展的现状和问题,梳理出了产业转型的总体思路,从而得出了城市产业转型的实施路径。 相似文献
105.
With the growth in project management as a form of work organisation in many sectors of the economy has come the significant rise in the number of project managers and project team members. This change in work organisation brings issues in forging career paths and determining career support in work situations that are often dynamic, short lived and intense. In the relatively small but substantially robust Australian economy, a unique labour market and the tyranny of distance bring their own difficulties. Innovative and collaborative project structures and increasing prevalence of contract work provide both challenges and opportunities for new career pathways in many industries. A growing percentage of Australia's workforce is employed in project-based or project-oriented organisations, leading to the claim that Australia is a project-based economy. This provided a context for our research into the career paths and the issues of career management for project managers working in a project based economy. Using in-depth interviews with project managers from three industry areas we found generational and gender differences in experiences of work, workplace support and mentoring for career development. For a continued strong performance in this economy, organisations that employ project personnel will need to consider how they will ensure the supply of high quality project professionals into the future. 相似文献
106.
Taking path dependence seriously: an historical institutionalist research agenda in planning history
Andre Sorensen 《Planning Perspectives》2013,28(1):17-38
This paper outlines an historical institutionalist (HI) research agenda for planning history. HI approaches to the understanding of institutions, path dependence, positive feedback effects in public policy, and patterned processes of institutional change offer a robust theoretical framework and a valuable set of conceptual and analytic tools for the analysis of continuity and change in public policy. Yet, to date, there has been no systematic effort to incorporate historical institutionalism into planning history research. The body of the paper proposes planning history relevant definitions of institutions, path dependence, critical junctures, and incremental change processes, outlines recent HI literature applying and extending these concepts, and frames a number of research questions for planning history that these approaches suggest. A concluding section explores the potential application and leverage of HI approaches to the study of planning history and international comparative planning studies and outlines a research agenda. 相似文献
107.
该文从平面的视角出发,对高层建筑基本平面形式选择、总平面布局对城市风环境带来的影响进行分析.高层建筑的不同基本平面形式,以及总平面布局中朝向、尺度、外部空间等方面的不同设计决策,对城市总体通风的影响有显著差异.根据定性分析,以及PHOENICS流体动力学软件的模拟结果,总结高层建筑设计中需要考虑的平面选型和布局策略,以保证城市风道畅通,提高城市总体通风效率. 相似文献
108.
为减少建筑基坑开挖对基坑围护结构变形的影响,提出利用动态规划理论分析大型基坑分区开挖最优路径的方法。结合工程实例,以基坑最大竖向位移和地下连续墙最大水平位移为目标函数,建立了基坑开挖路径分析的动态规划模型,并分析出了现有地质条件下基坑施工的最优开挖路径。其分析方法与结果可供类似工程参考。 相似文献
109.
立足于滇西典型欠发达中小城市保山市城镇化现状特征,剖析了保山市城镇化竞争优势,探讨了保山新型城镇化的发展路径,提出了保山新型城镇化发展综合策略:引导整合优势资源,强化产业支撑;注重城市整体功能建设,提升城市综合承载力;挖掘城镇特色,明确城镇化发展路径。 相似文献
110.
结合扬州城建史,对其城河关系与城市功能的发展演变进行了阶段性分析,同时折射出古城扬州的发展轨迹,并对当前滨水区整治的重要措施和成效进行了概述,以供参考借鉴。 相似文献