水锁作用对煤体瓦斯涌出影响的研究与发展

矿井工作面瓦斯超限严重影响着矿井安全生产和生产效率,现用解决该问题的方法存在局限性,不能广泛适用于所有矿井。针对该问题,采用水及含添加剂水阻碍和延缓煤体内瓦斯解吸速度,以达到降低工作面瓦斯涌出量的目的。本文通过对其抑制原理相关研究的介绍,为同类工作面瓦斯超限治理提供基础理论依据。     

基于NETSTARS运用定床水理原理在河道疏浚中的应用

疏浚大多用于河道的过分淤积,拓宽则用于通水隘口的消除。而随着时空的演变河床疏浚与河槽拓宽的进行所需考虑的因子越来越多,故疏浚进行前应尽量考量整个河道的河性以及施工后可能引致的变动,使能维持预期的效果,并避免造成负面效应。本文主要以涧河为研究对象,利用NETSTARS拟似二维水理输砂模式,探讨河道疏浚后的水理与输砂演变趋势等相关课题。     

基于DEA方法的中国农业水资源利用效率研究

[目的]以我国各省市2008~2015年农业水资源利用效率为研究对象,探究我国农业水资源利用效率的规律与特点,并基于此提出促进农业水资源合理利用的建议。[方法]主要采用了文献研究法、统计分析法和数据包络分析(DEA)法。通过文献搜集我国各省市2008~2015年与农业水资源利用相关的数据,构建DEA模型,对我国近年来农业水资源利用效率进行评价。[结果]2008~2015年,我国农业水资源利用效率在0.80上下浮动。各省市农业水资源利用效率随时间变化趋势不同。甘肃和上海的农业水资源利用效率涨幅最大,年增长率分别为4.39%和2.74%;山西、江西以及陕西省的农业水资源利用效率整体趋于下降;浙江、湖南以及陕西和新疆的农业水资源利用效率有先上升后下降的特点,表现出明显的波动。此外,农业水资源利用效率区域分化明显。东部地区农业水资源利用效率一般高于0.80,中部地区位于0.60~0.80,西部地区农业水资源利用效率一般低于0.60。[结论]2008~2015年,我国农业水资源利用效率表现出一定的时间差异性和空间差异性。时间差异性:我国农业水资源利用效率一直处于较高水平并呈现逐年增长趋势,不同省份的农业水资源利用效率随时间变动趋势各异。空间差异性:东部地区农业水资源利用效率最高,中东部地区农业水资源利用效率甚至达到了最优,中部地区其次,西部省区农业水资源利用效率最低。农业水资源利用效率受当地政策、经济发展水平、农业发展水平、水资源总量和人口压力等因素影响严重,今后应针对不同地区采取不同措施解决实际问题。     

干旱区绿洲全要素农业水资源利用效率时空分异研究——以新疆为例

选取2004—2014年新疆14个地州市际面板数据,基于投入导向的超效率DEA模型,依托共同前沿理论方法,采用全要素水资源效率测度思路,对新疆地州市以及分区域农业水资源利用效率进行测度,并对其开展时空分异研究。研究结果表明,新疆地州市农业水资源利用效率呈现不断增长趋势,三大区域农业水资源利用效率呈现出北疆、东疆及南疆依次递减规律;南疆主要地区、乌鲁木齐市与阿勒泰地区农业用水处于无效率状态,伊犁州直属县(市)、博尔塔拉自治州农业用水处于低效率状态,克拉玛依市、昌吉回族自治州、塔城地区、巴音郭勒自治州、和田地区、吐鲁番地区等农业用水处于高效率状态。     

基于耦合协调度模型的南京市用水效率与经济发展关系

基于2007—2014年南京市用水效率与经济发展的时间序列数据,构建南京市用水效率系统与经济发展系统间的耦合协调度模型,探讨南京市在2007—2014年期间用水效率与经济发展之间的动态均衡关系。首先对用水效率系统和经济发展系统的综合状况进行评价,然后对两系统的耦合协调度进行定量分析。结果表明:2007—2014年南京市用水效率和经济发展水平都有大幅度增长;两者的耦合协调关系在波动中逐渐优化,2007年处于低度协调耦合阶段,2008年处于中度协调耦合阶段,2009—2014年处于高度耦合协调阶段;只有提高用水效率与经济发展并举,才能保持耦合协调度的增长趋势。最后针对用水效率系统和经济发展系统存在的不足,提出在用水效率方面优化用水结构、加强水质污染治理,经济发展方面则调整经济结构、增强经济活力等建议。     

Urban Warfare Ecology: A Study of Water Supply in Basrah

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 It interprets an extensive range of unpublished literature through a frame that incorporates the accumulation of direct and indirect impacts upon the hardware, consumables and people upon which urban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.     

Natural and anthropogenic influences on the year-round temperature dynamics of air and water in Postojna show cave,Slovenia

Air and groundwater temperatures were measured in a rimstone pool in Postojna Cave, to advise evaluation of the impact of natural and anthropogenic influences related to heat being initially transmitted into cave air by visitors. Such heat can accumulate both in the rock mass and in water. Results show that attention must be paid to temperature changes of rimstone pool water rather than those of cave air, especially during the winter. Thanks to good ventilation deep inside the cave, short-term air temperature increases related to higher visitor numbers have not influenced flowstone precipitation or the cave fauna. However, this situation might change if winter visitor numbers increased greatly. This study does not support a suggested increase in winter visits (currently the tourism low-season) and reduction of summer visits (currently the tourism high-season).     

Nondiscretionary residential water use: the impact of habits and water‐efficient technologies

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.     

反映价格变化趋势的建设项目经济评价方法探讨──兼论对水利水电项目经济评价及其方案比较的影响

提出一种反映价格变化趋势的建设项目经济评价方法,导出在全程平均价格年变化率和分期平均价格年变化率条件下的价格与基准年固定价格的换算系数,进一步推导了各种经济评价指标的计算公式。用典型算例说明:在正常的价格变化范围内,价格变化对建设项目经济可行性评价结果和方案比较结果可能产生颠覆性的影响,因此反映价格变化趋势是必要的。该方法为在建设项目经济评价中反映价格趋势的变化提供了一种可行技术,使评价结果更符合实际。     

水资源资产量核算研究综述

为了完善水资源资产负债表的编制以及提高水资源资产化管理水平,从水资源资产概念界定及其分类、水资源循环对水资源资产的影响、水资源资产账户与资产量核算方法 3个方面概述了国内外对水资源资产的研究进展、成果和方法。认为目前水资源资产的研究仍处于起步阶段,以概念探讨和定性分析为主;对水资源循环理论研究较多,对水资源资产的循环过程研究较少;对水资源资产量核算的研究主要集中在水资产账户方面,且系统性的研究较少。未来对水资源资产核算的研究应重点关注:水资源资产循环理论研究、潜在水资源资产量核算方法研究、区域水资源资产量核算方法研究等领域。