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991.
工程项目费用管理是一项系统工程,需要进行全过程、全方位、多角度的策划。从理论原则、制度流程、实施阶段和知识体系四个维度,阐述我国工程项目承包商费用管理中的不足,剖析原因并提出解决策略。 相似文献
992.
BIM介入高等教育工程管理类专业课程体系研究 总被引:1,自引:0,他引:1
在分析BIM对项目管理十大知识领域的支持性作用以及BIM经理和项目经理区别的基础上,从课程系统建立、教材资料、教师以及学生四个方面分析高校工程管理专业普及BIM教育的障碍,结合技术类、经济类、管理类和法律类四个工程管理专业课程平台探讨BIM的介入,然后提出横向合作和纵向引进相结合的组织方式、现实和虚拟相结合的技术手段、理论与实践相结合的授课形式以及单项课程逐步过渡到平台框架集成的BIM高等教育普及路径。 相似文献
993.
Fritz Kleemann Jakob Lederer Philipp Aschenbrenner Helmut Rechberger Johann Fellner 《Building Research & Information》2016,44(1):51-62
A prerequisite of the efficient recycling of demolition waste and its evaluation in terms of the material specific recycling rates is information on the composition of the building material stock (as the source of future demolition waste). A practical method is presented that characterizes the material composition of buildings prior to their demolition. The characterization method is based on the analysis of available construction documents and different approaches of on-site investigation. The method is tested in different buildings and the results from four case studies indicate that the documents are useful to quantify bulk materials (e.g. bricks, concrete, sand/gravel, iron/steel and timber). However, on-site investigations are necessary to locate and determine the trace materials such as metals (e.g. copper and aluminium), or different types of plastics. The overall material intensity of the investigated buildings ranges from 270 to 470?kg/m³ gross volume. With ongoing surveys about the composition of different buildings, the collected data will be used to establish a building-specific database about the amount of materials contained in Vienna's building stock. 相似文献
994.
Planning approaches that integrate road infrastructure and other land uses are being increasingly applied. Dealing with functional interrelatedness and stakeholder fragmentation are the main reasons for this. This article conceptualizes and analyses why and how such integrated approaches can be applied effectively throughout consecutive stages of infrastructure planning. The two case studies illustrate that the concept of integration is applied for strategic as well as operational reasons, and they reveal that these reasons may alternate throughout the planning process. Effective integration is therefore dynamic: it appropriately focuses on strengthening the socio-economic perspectives of a region for the longer term, as well as on the relations between different land uses that are physically adjacent and competing for space within a smaller area. Due to fragmented institutional contexts, successfully dealing with interrelatedness requires an intense level of interaction amongst involved actors. Such “co-production” of visions and plans has two important characteristics: negotiation, and learning about each other’s goals. Ultimately the case studies also show that planning at the infrastructure–land use interface needs institutional mechanisms to guide the alterations between strategically and operationally inspired integration. Contracts with private parties, public participation, and positive conditions for learning about each other’s referential frames are examples of the institutional mechanisms encountered in this study. 相似文献
995.
Frequent water stress episodes affecting urban hubs have caused a shift in urban water management towards integrated approaches and motivated a search for alternative water resources. Large-scale rainwater harvesting on the municipal scale can overcome the disadvantages of climate dependence and the volume restrictions associated with small-scale collection facilities. In this paper, two tools based on the urban metabolism concept are used to determine the water self-sufficiency potential of urban systems from urban runoff: a simple water self-sufficiency potential indicator and a socioeconomic water flow accounting scheme, which includes water losses. Both tools are applied to a densely populated coastal area that exemplifies urban centres in the Mediterranean. This approach is useful for regions with restricted data availability on water use and facilitates information dissemination to policy makers. The results indicate a significant water self-sufficiency potential for the area of study, even under projections of reduced precipitation in the area. 相似文献
996.
Franz Tscheikner-Gratl Robert Sitzenfrei Wolfgang Rauch Manfred Kleidorfer 《Structure and Infrastructure Engineering》2016,12(3):366-380
In the past decades, the main focus of water supply management has moved from construction of new water supply networks to rehabilitation and adaptation of the existing infrastructure. The decision-making process for the rehabilitation management relies heavily on the quality of the applied deterioration model. A recurring problem in the application of such models relates to the quality and availability of network data. These data are often incomplete or unreliable because building measures and damages are only documented properly recently and the recovery of older data is difficult and expensive. A key point in rehabilitation planning is therefore data collection and data reconstruction. Consequently, the aim of this paper is to present a methodology for the enhancement of the available data of water supply networks and the prognosis of the necessary rehabilitation rates under limited data availability. Results indicate that the presented data reconstruction technique has advantages as compared to traditional data extrapolation. It also allows the reconstruction of fragmentary data about existing water supply and wastewater collection systems for the operating utilities. However, it cannot be used for reconstructing failure types as well as the whole information on pipes (e.g. more than two missing information). 相似文献
997.
Christina Plati Panos Georgiou Vasilis Papavasiliou 《Structure and Infrastructure Engineering》2016,12(9):1127-1136
This article aims to investigate the feasibility of incorporating of an artificial neural network (ANN) as an innovative technique for modelling the pavement structural condition, into pavement management systems. For the development of the ANN, strain assessment criteria are set in order to characterise the structural condition of flexible asphalt pavements with regards to fatigue failure. This initial task is directly followed with the development of an ANN model for the prediction of strains primarily based on in situ field gathered data and not through the usage of synthetic databases. For this purpose, falling weight deflectometer (FWD) measurements were systematically conducted on a highway network, with ground-penetrating radar providing the required pavement thickness data. The FWD data (i.e. deflections) were back-analysed in order to assess strains that would be utilised as output data in the process of developing the ANN model. A paper exercise demonstrates how the developed ANN model combined with the suggested conceptual approach for characterising pavement structural condition with regard to strain assessment could make provisions for pavement management activities, categorising network pavement sections according to the need for maintenance or rehabilitation. Preliminary results indicate that the ANN technique could help assist policy decision makers in deriving optimum strategies for the planning of pavement infrastructure maintenance. 相似文献
998.
Vulnerability analysis plays a key role in the metro operation system, since the metro operation security has become more important than ever. The vulnerability management is a systems engineering, it covers different departments of the metro operation company. A successful vulnerability management needs the close cooperation and coordination between them. However, it has blocked a successful vulnerability management due to lack of the common knowledge basis. This paper applies ontology into the vulnerability analysis of the metro operation system and illustrated the major design ideas of the ontology model. Examples are given as well to demonstrate the implementation of knowledge reasoning based on the ontology. The ontology was also evaluated through expert evaluation for further improvement. By using this technology, a common knowledge base of the vulnerability management in the metro operation system can be built. It provides information sharing, communication and collaboration for all the participants in the system for decision-making. Moreover, further development of the intelligent application can be built based on it, efficiently increasing the management level of the vulnerability. 相似文献
999.
Muhammad Shafqat Ali Muhammad Sagheer Aslam M. Saeed Mirza 《Structure and Infrastructure Engineering》2016,12(11):1381-1394
This paper deals with the development of a framework for assessment of sustainability of bridges, including related technical, economic, environmental and social issues. Sustainable infrastructure assets require diligent conception and design of facilities (with diligent choice of materials and construction techniques), high quality construction, and operations, involving routine maintenance, with optimised life-cycle performance and costs, and minimum impact on the environment over a stipulated long service life and beyond. Partial details of design, construction, maintenance and rehabilitation/renovation of the four versions of the 3-km long Victoria Bridge (1859, 1898, 1958 and 1988) are summarised, along with the partial details of design, construction, severe deterioration and subsequent rehabilitation of the nearly 6-km long, 6-lane Champlain Bridge. Sustainability of both bridges was assessed by implementing the proposed sustainability framework developed in this research programme, along with the use of the analytical hierarchy process which involved evaluation of pairwise comparison of the various categories to assist with evaluation of the sustainability scores. These scores indicate that all four forms of Victoria Bridge (1859, 1898, 1958 and 1988) are partially sustainable, or sustainable, while the Champlain Bridge is unsustainable. This framework can be appropriately adapted for assessing the sustainability of other infrastructure assets. 相似文献
1000.
Mountain ridges are valued by the Korean people as major and critical sources of natural resources and environment. Despite their recognised values, continuous exploitation and infrastructure development in forestlands have been causing large-scale degradation in mountains throughout the country. In response to this problem, our study supports recent efforts by the government to designate protection areas across the country. We build on the traditional classification of mountain ridges and apply a terrain-based spatial model to derive mountain ridge area boundaries. Based on the well-known mountain ridge system of the Korean peninsula, established in 1769, our approach was to select mountain ridgelines and boundaries using a terrain-based spatial model. The selected areas are generally located at high elevations with undulating terrain. They include a relatively large portion of ecologically important areas. A large portion of non-nationally owned forest is also found in the selected areas. Ecological importance and property rights would likely cause significant debate and conflicts among different social groups regarding designation of legally binding protection areas. Our model provides an explicit, scientific basis for the rigorous evaluation and area prioritisation as part of the protection area designation process. Application of our model can facilitate conversation on the country’s mountain ridge asset and public participation in the decision-making process. 相似文献