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101.
Metallurgist - The article provides a brief assessment of the current state of power supply units at metallurgical plants and prospects for their future development. The principal power-supply... 相似文献
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C. Makropoulos D. Nikolopoulos L. Palmen S. Kools A. Segrave D. Vries 《Urban Water Journal》2018,15(4):316-328
Infrastructure planning for Urban Water Systems (UWSs) is challenged by, inter alia, increasing uncertainty in both demand and availability of water and aging infrastructure, and this is already impacting the climate-proofing of cities. In this context, the idea of resilience has been gradually embraced by the water sector, but the term itself is not yet universally defined, nor operationalised. Here, we propose a methodology to assess the resilience of a UWS, defining it as the degree to which the UWS continues to perform under increasing stress. A resilience assessment method is then proposed as a ‘stress-test’ of UWS configurations, under increasingly more stressful scenarios. We then demonstrate a toolbox assembled for the proposed analysis using, as a proof of concept, a semi-synthetic case study. Results are promising, suggesting that the approach could assist in the uptake and evolution of resilience thinking in strategic water infrastructure decision making, leading to water-wiser cities. 相似文献
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随着交通量不断增长,车辆重载、超载现象日益严重。沥青路面通车一段时间后,常常出现不同程度的横向裂缝。分析了沥青路面横向裂缝产生的原因和危害,同时提出了相应的裂缝防治措施。 相似文献
106.
K.E. LANSEY C. BASNET L. W. MAYS J. WOODBURN 《Civil Engineering and Environmental Systems》2013,30(3):211-226
The scheduling of maintenance for water distribution systems is a complex task encompassing a wide range of alternatives. The methodology presented in this paper can consider the major piping alternatives of replacing and cleaning, and relining. It also considers the potential of pumping improvements while accounting for the costs of maintenance, failure and operations for a multiple-period planning horizon. To solve the problem a nonlinear optimization model is linked with a network simulation model. The application showed that the procedure can determine solutions in reasonable times. 相似文献
107.
I.P.L. Coleman J.A. Blair M.E. Hilburn 《The International journal of environmental studies》2013,70(3-4):187-191
The effect of a number of dietary and synthetic chelating agents on the intestinal absorption of lead has been examined using the everted sac preparation and the tracer isotope 203Pb. All the agents examined increased lead transport into the serosal compartment. An explanation of the way in which these agents modify the model to describe lead transport is proposed. 相似文献
108.
John R. Hamburg Roger L. Creighton 《Journal of the American Planning Association. American Planning Association》2013,79(2):67-72
The planning of community facilities requires accurate quantitative estimates of the area, type, intensity, and location of land uses required by the growth of urban activities. The distribution of these activities and the intensity of their use of land are highly related to accessibility as measured by distance from the CBD. This paper outlines a procedure whereby area-wide estimates of future population and economic activity can be distributed to small subareas so that measures of local land requirements may be obtained. 相似文献
109.
Roger L. Creighton J. Douglas Carroll Jr. Graham S. Finney 《Journal of the American Planning Association. American Planning Association》2013,79(2):96-103
In city planning, data-processing machines permit the rapid handling and summarization of data in housing, renewal, land use, transportation, and basic urban research. Electronic computers. specifically, are exciting because they offer a means of solving complex city planning problems, especially in forecasting land use and travel demand. For most planning operations punched card data processing is superior to other processes. The functions of these machines are described herein and three examples of data processing are elaborated on. In future years, planning techniques may have to be altered considerably to take advantage of the potentials of data processing. 相似文献
110.
在我国当前快速城市化的进程中,城市空间结构绩效的优劣直接影响着城市的健康和可持续发展。文章通过回顾我国城市空间结构绩效的研究概况,对其内在机理、评价指标体系、良好绩效的空间结构形态以及提高城市空间结构绩效的措施等主要研究内容进行梳理和评析,并在此基础上展望未来的研究方向,以期有助于该领域在我国的研究获得新的突破。 相似文献