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1.
Hamid Azizi Bondarabady 《Journal of Urbanism》2018,11(2):202-232
According to many researchers and scholars, religious beliefs can be considered as the most influential factor in forming Muslim urban spaces and their architectural elements. In fact, historical cities reflect the culture and beliefs of their residences. Among all historical places in Iranian cities, the historical texture of the city of Yazd, especially the quarters since the age of Qajar dynasty, are well preserved. The present study aims at identifying the Islamic principles and values influencing the formation of architectural spaces and the extent of their applications in one of the historical quarters known as Golchinan. The results of the conformation of the theoretical findings with the data acquired from field studies revealed that almost 90% of the urban and architectural spaces (e.g. residential areas, mosques, bazaars, and pathways) in Yazd are directly influenced by Islamic principles. In other words, there is a strong conformity between the accepted Islamic values of the society and what actually was applied to urban constructions during Qajar dynasty. 相似文献
2.
Nicholas Vergeylen Kenneth Srensen Pieter Vansteenwegen 《International Transactions in Operational Research》2020,27(6):2695-2714
This paper introduces an efficient algorithm for the bike request scheduling problem (BRSP). The BRSP is built around the concept of request, defined as the pickup or dropoff of a number of identical items (bikes) at a specific station, within a certain time window, and with a certain priority. The aim of the BRSP is to sequence requests on (and hence determine the routes of) a set of vehicles, in such a way that the sum of the priorities of the executed requests is maximized, all time windows are respected, and the capacity of the vehicles is not exceeded. The generation of the set of requests is explicitly not a part of the problem definition of the BRSP. The primary application of the BRSP, from which it derives its name, is to determine the routes of a set of repositioning vehicles in a bike sharing system, although other applications exist. The algorithm introduced in this paper is based on a set of related greedy randomized adaptive search procedure followed by variable neighborhood descent (GRASP + VND) operators embedded in a large neighborhood search (LNS) framework. Since this paper presents the first heuristic for the BRSP, a computational comparison to existing approaches is not possible. We therefore compare the solutions found by our LNS heuristic to those found by an exact solver (Gurobi). These experiments confirm that the proposed algorithm scales to realistic dimensions and is able to find near‐optimal solutions in seconds. 相似文献
3.
Marion Markwick 《Urban Research & Practice》2018,11(2):87-110
The paper aims to unfold the narrative of development in a creative cluster project for the regeneration of Strait Street in Valletta, Malta. This is approached by first examining the distinctive, historically contentious background of the neighbourhood and, thereafter, unpacking the development narrative of policy documents and the discursive and material constructs about the creative city approach to regeneration strategies in the city. Using a ‘system-wide’ analytical framework, this material is then scrutinized to gain an understanding of the specificities involved and, finally, discuss the crucial features of the key dimensions elucidating the potential strengths and weaknesses of the case 相似文献
4.
City logistics is one of the significant branches of supply chain management, dealing with the logistics and transportation activities in urban areas. This research area has recently appropriated an exponential growth of publications. This paper presents a bibliometric analysis along with a systematic literature review to organise the results of surveying more than 370 papers and research works published since 2010. We identify the top contributing research topics. The most common keywords used in the city logistics literature are referred to in order to propose six research categories identifying the main innovative research perspectives. 相似文献
5.
为了解玉溪市某工业园区大气PM_(2.5)中重金属污染特征,于2017年3月至2018年3月在玉溪市某工业园区采集PM_(2.5)样品共70个。利用微波消解,ICP-MS方法检测Cr、As、Cd、Pb四种重金属的质量浓度并分析其污染特征。结果表明,玉溪市某工业园区大气PM_(2.5)日均质量浓度在10μg·m~(-3)~75μg·m~(-3),而PM_(2.5)中四种重金属的浓度范围在0.003~0.377μg·m~(-3),并且浓度由高到低依次为PbAsCr Cd,其中As超过国家质量指标限值。因此,应对玉溪市废气排放采取一定控制措施。 相似文献
6.
海绵城市建设PPP项目委托代理契约分析 总被引:1,自引:0,他引:1
针对海绵城市PPP(Public-Private Partnership)项目建设、运营管理问题,为了降低由于项目参与的各方掌握信息、地位的不对称而产生的道德风险、维护各参与方的合法权益,基于一定的前提假设,构建海绵城市建设PPP项目契约模型,利用优化理论分别从代理企业和政府方两个主体的效用对模型的各个参数相关关系进行了分析,并利用数值模拟讨论了监控机制各参数对政府方监控意愿的影响。最后,结合常德市海绵城市PPP项目建设的案例,分别分析在当前考核机制下项目在建设、运营期可能存在的问题,并提出了相应的对策以解决这些问题。结果表明:代理企业的监控和激励措施具有互补性,海绵工程项目风险来源广泛,企业为规避风险会偏好零风险的固定收益,设定监控机制能激励企业更加努力的工作。 相似文献
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陈湘闽 《有色冶金设计与研究》2021,(1):32-35
根据近些年的城市隧道工程设计经验,介绍了隧道照明的设计依据、标准及基本要求,分析了城市隧道照明设计的照明标准值、灯具布置、应急照明、照明控制、配线、节能措施等方面内容,并对隧道照明工程设计实例进行了探讨。 相似文献