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161.
Water quality in the European Union is subject to legislation through directives that are applicable in all Member States. The directives specify a set of physical and chemical parameters that should be regularly controlled using a network of sampling points, with sampling based on the intended use of the water. This paper presents the results of a statistical comparison of the quality of water intended for human consumption at two different locations (the Canal de Benagéber and the Canal Júcar-Turia) near the town of Valencia (Spain). These are currently the only canals that could supply Valencia and other nearby towns with drinking water. The parameters considered in this paper are the ones specified in the European directives for determining the quality of water intended for human consumption. These directives specify that the 95th percentile of the distribution of each parameter should be used to assess water quality, so accurate estimation of these percentiles was essential in this paper. We found statistically significant differences among locations in chlorides, sulfates, temperature, coloration, and manganese, but the results varied depending on the statistical tests that we used; parametric methods gave better results than nonparametric methods.  相似文献   
162.
We evaluated whether growth rates of six fish species correlated with PCB concentrations in a moderately-to-heavily polluted freshwater ecosystem. Using a large dataset (n = 984 individuals), and after accounting for growth effects related to fish age, habitat, sex, and lipids, growth correlated significantly, but positively with lipid-corrected PCB concentrations for 4 of 6 species. Remaining species showed no correlations between growth and PCBs. Comparisons with regional, lentic growth averages for four species confirmed growth was on par and in three of four cases higher than regional averages in the PCB-polluted ecosystem. We conclude that for these species, at the range of concentrations examined, these PCBs do not exert negative impacts on growth. Rather, factors often cited as influential to growth were also driving growth trends in this study. Future studies that evaluate whether pollution affects growth must account for major growth drivers prior to attributing growth differentials to pollution alone.  相似文献   
163.
介绍了陕西省成品油生产、消费、流通等环节的现状,针对各环节潜在问题提出了优化建议:加强采炼销环节管理,实现采炼销动态平衡;加强配送中心建设,高效链接一次物流和二次物流环节;加强信息网络建设,高度集成各环节管理系统和油品信息资源;加强全链条环节的油气回收,建立污染排放清单。  相似文献   
164.
根据对呼略矿采场围岩控制的研究 ,提出通过控制煤层底板来管理顶板 ,是采场围岩控制的重要方面。在矿压观测的基础上 ,经过科学分析与设计 ,增设单体支柱下的柱鞋 ,能有效地增强整个支护系统的刚度 ,达到控制和管理好顶板 ,实现安全生产的目的  相似文献   
165.
Crumb rubber can be produced from scrap tires in a wide range of particle sizes and quality levels. Ideally, the revenue stream includes tipping fees paid to receive the raw materials; sales of variously-sized crumb products to different end-user markets; and potential sales of scrap metal and fiber contained within the tires. General demand has been increasing, and submarkets for crumb products are growing in size and variety. However, the optimistic expectations of potential investors and government agencies contrast sharply with the experiences of many current and former producers. Production planning and operation is complex, real-dollar crumb prices have fallen, and many producers recount difficulties finding stable markets and competing against newer, state-subsidized competitors. This paper examines the engineering economics of crumb rubber facilities. Following a literature review and interviews with producers, a financial model of a nominal processing operation was created to aid the analysis of different market, crumb size, and production scenarios. The profitability of a crumb facility appears to be particularly sensitive to crumb rubber prices, operating costs, and raw material availability. Better analysis of market and production impacts on financial viability for proposed processing facilities would aid overall market efficiency.  相似文献   
166.
当前我国安全管理存在的问题分析及对策探讨   总被引:11,自引:7,他引:11  
当前我国的安全生产形势依然严峻 ,主要原因是人为所致 ,而人为原因与管理有着直接的联系。笔者分析了当前安全管理主要存在的 5个方面的问题 :安全管理严不起来 ,落实不下去 ;安全管理基础薄弱 ;安全管理体制不顺 ;行业安全管理力度不够 ;安全管理中存在着腐败现象。同时提出了加强安全科学管理 ;强化安全管理基础工作 ;重视行业安全管理 ;强化安全法制与监管 ;实行全员安全目标管理 ;夯实班组基层安全管理等 6项对策  相似文献   
167.
激励劳动者安全行为实现企业安全化生产   总被引:2,自引:0,他引:2  
分析人的不安全行为是造成伤亡事故的重要原因。例举人的心理和社会心理因素以及人的安全意识、感觉和知觉、记忆和思维、情感和情绪等对人的安全行为的影响。提出激励劳动者安全行为,加强企业安全生产科学管理,为劳动者安全和健康服务,实现企业安全化生产的见解  相似文献   
168.
This paper introduces a bottom-up approach towards sustainability which is called the Island approach. The basic assumption of ‘Islands of Sustainability’ is that development towards sustainability can be introduced starting from small sustainable regions. An Island is an area where sustainability is reached locally. Key points to create a sustainable region are communication activities, such as exchange of matter, energy, information, culture, capital and persons within the regional network and with the environment. One of the main theses is that sustainability is linked to the complexity of the regional network. The intensity, the speed and the comprehensive of internal and external interactions, as well as the connectedness of the regional network, have to be changed in order to reach local sustainability.Relations between different approaches such as the Cleaner Production approach, the Industrial Ecology approach and the Island approach are investigated. It is assumed that a combination of these approaches will lead to sustainability, which might not be the case with one approach in isolation. All concepts are based on the new Network Paradigm, which is a reduction of the holistic world view. Cooperation on different hierarchical levels, from the interfirm level up to the interregional level, becomes an important part of behaviour. Networks, such as information networks or matter-flow networks, are introduced and become most important with regard to sustainability.  相似文献   
169.
清洁生产是环境管理的有效措施   总被引:1,自引:0,他引:1  
抚顺市是辽宁省清洁生产示范城市之一。通过在全市 1 2家企业推行清洁生产工作的实践证明 :清洁生产必须与现行的环境管理制度如排污收费、限期治理等有机的结合起来 ,以促进企业清洁生产的顺利进行。  相似文献   
170.
本文建立了新疆生产建设兵团农垦城镇类、等、级及基准地价的城镇土地等级体系,为兵团农垦城镇不同层次的土地管理提供了科学依据,对深化我国土地有偿使用制度改革,建立健全合理的土地市场,实现土地资源资产化等具有较好的理论和实践探索意义。  相似文献   
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