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91.
Several studies published in the last few decades have demonstrated a low price‐elasticity for residential water use. In particular, it has been shown that there is a quantity of water demanded that remains constant regardless of prices and other economic factors. In this research, we characterise residential water demand based on a Stone‐Geary utility function. This specification is not only theory‐compatible but can also explicitly model a minimum level of consumption not dependent on prices or income. This is described as minimum threshold or nondiscretionary water use. Additionally, the Stone‐Geary framework is used to model the subsistence level of water consumption that is dependent on the temporal evolution of consumer habits and stock of physical capital. The main aim of this study is to analyse the impact of water‐saving habits and water‐efficient technologies on residential water demand, while additionally focusing attention on nondiscretionary uses. This is informed by an empirical application using data from a survey conducted among residents of Brisbane City Council, Australia. The results will be especially useful in the design of water tariffs and other water‐saving policies.  相似文献   
92.
This article assesses the impact of armed conflict on the drinking water service of Basrah from 1978 to 2013 through an ‘urban warfare ecology’ lens in order to draw out the implications for relief programming and relevance to urban studies. It interprets an extensive range of unpublished literature through a frame that incorporates the accumulation of direct and indirect impacts upon the hardware, consumables and people upon which urban services rely. The analysis attributes a step‐wise decline in service quality to the lack of water treatment chemicals, lack of spare parts, and, primarily, an extended ‘brain‐drain’ of qualified water service staff. The service is found to have been vulnerable to dependence upon foreign parts and people, ‘vicious cycles’ of impact, and the politics of aid and of reconstruction. It follows that practitioners and donors eschew ideas of relief–rehabilitation–development (RRD) for an appreciation of the needs particular to complex urban warfare biospheres, where armed conflict and sanctions permeate all aspects of service provision through altered biological and social processes. The urban warfare ecology lens is found to be a useful complement to ‘infrastructural warfare’ research, suggesting the study of protracted armed conflict upon all aspects of urban life be both deepened technically and broadened to other cases.  相似文献   
93.
李源 《价值工程》2014,(32):94-96
矿井水害的预防预报是指查清矿井水文地质条件,对水害做出分析判断。本文以山西成家庄煤矿防治水为例,分析了矿井充水因素,以理论结合实际,为预防矿井水害提供依据。  相似文献   
94.
长久以来,前辈学人对于《史记》中平阳君赵豹“秦以牛田(之)水通粮”一语解释多有不同,或以为是秦“以牛耕田,以水漕粮”,或以为是秦“以发源于‘牛田’之地的河流进行漕粮”,但均未形成定论。本文认为,先秦时期关中水资源丰富,渭河支流多可航运,加上关中水利发达,于是秦国利用与渭河支流连通的田间大渠——“浍”渠进行粮食漕运,即所谓“秦以牛田水通粮”。且战国后期,随着秦对外战争规模的扩大,粮秣耗费日增,使用“牛田水通粮”已十分必要。  相似文献   
95.
While researchers in the growing field of urban political ecology have given significant attention to the fragmented hydroscape that characterizes access to drinking water in the global South, so far the (re)production of other urban waters and its related power relations have been underexplored. This article seeks to contribute to filling this gap by exploring the everyday negotiations over access to urban water bodies, in particular ponds. These are understood as a composite resource that is simultaneously water, land and public space. This analysis draws on a case study from a small city in West Bengal, India, and is based primarily on data from open interviews with different actors with a stake in urban ponds. The article demonstrates that in a context of ambiguity of the statutory governance regime and fragmented control, the (re)production of the pondscape is embedded within complex relationships of power whereby social marginalization can be offset at least momentarily by local institutions such as neighbourhood clubs and political parties.  相似文献   
96.
97.
肖淑红  余扬 《价值工程》2010,29(24):124-124
本文主要论述了深基坑围护的若干设计理论及施工技术,并结合工程实际进行案例分析,探讨结合理论知识指导实际工程管理的作用。  相似文献   
98.
We develop a structural risk‐neutral model for energy market modifying along several directions the approach introduced in Aïd et al. In particular, a scarcity function is introduced to allow important deviations of the spot price from the marginal fuel price, producing price spikes. We focus on pricing and hedging electricity derivatives. The hedging instruments are forward contracts on fuels and electricity. The presence of production capacities and electricity demand makes such a market incomplete. We follow a local risk minimization approach to price and hedge energy derivatives. Despite the richness of information included in the spot model, we obtain closed‐form formulae for futures prices and semiexplicit formulae for spread options and European options on electricity forward contracts. An analysis of the electricity price risk premium is provided showing the contribution of demand and capacity to the futures prices. We show that when far from delivery, electricity futures behave like a basket of futures on fuels.  相似文献   
99.
This article investigates the relevance of the theories of implicit contracts and spot market model to the skill-level wages in Finland. We use linked worker-firm panel data over the period from 1991 to 2004, which included major institutional and technological changes. We find similar patterns in the wage flexibility of primary and highly educated workers: their wages increased with the decreasing spot market unemployment rate after the EU membership still exhibiting some weak backward linkages. The wages of the secondary-educated did not follow the decreasing spot market unemployment, but instead some signs of the full commitment risk sharing were found.  相似文献   
100.
重复扰动下富含水地层的加固技术   总被引:1,自引:0,他引:1  
随着城市地铁、地下空间、铁路和公路隧道的大规模建设和发展,工程中要面对的各种复杂地层的地基处理及松软地层改良问题越来越多。文章结合广州市轨道交通5号线(大坦沙~中山八盾构区间)2#联络通道塌方后,在重复扰动的富含水地层进行加固处理的成功经验,详细地介绍了采用无收缩双液二重管注浆技术在重复扰动下富含水地层中的注浆加固方法。  相似文献   
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