光纤通信技术在渠道长距供水信息系统中的设计与应用

长距离供水渠道地处偏远,点多线长,采用信息化技术手段进行远程集中控制成为必然,光纤通信技术作为远控的基础显得尤为重要。文章介绍了南干渠供水信息系统中建设光纤通信系统的必要性和重要性,以及光纤通信系统结构、系统链路和系统设备选型,以达到无人值班、少人值守、集中控制的设计目标。     

龙滩水电站工程融资和资金使用管理

龙滩水电站工程80％的建设资金来源于银行贷款,融资费用较高。因此,必须优化债务结构,减少利息支出;加速资金周转,提高资金使用效率;严格工程投资控制制度和工程预算管理制度;加强资金使用管理,以控制和降低工程造价。     

The water–energy nexus: energy use for water supply in China

China’s strategy to meet increasing water demand is to increase the use of inter-basin transfer water and unconventional water. This study evaluates the energy requirements of this strategy by disaggregating and quantifying the regional energy use for water supply in 2020 and 2030; the energy use in 2014 is calculated to represent the present situation. We find that the energy use for water supply in 2014 amounted to 81 billion kWh. This value is expected increase to 90 and 109 billion kWh by 2020 and 2030, respectively. In 2030, the urban domestic sector will overtake the agricultural sector as the most energy-intensive sector, with major contribution from inter-basin transfer water.     

基于水利网格的资源整合与应用

在探讨网格技术的基础上,以主题信息服务、按需计算服务、个性化决策服务的高效化和便捷化为目标,构建了水利网格平台框架及平行系统,分别实现了异构信息的高效集成、计算力资源调度及服务可视化、卫星遥感MODIS数据的按需计算服务、基于平行系统的洪水预报以及基于网格系统的仿真模拟环境。以水利网格作为基础平台的资源整合与应用方案,能够有效的解决多种水利业务的分析、处理问题,并在一定程度上辅助支持了预报和决策。     

Groundwater Utilization and Management in the State of Kuwait

Abstract

The main brackish groundwater resources in the State of Kuwait are the groundwater located in the Kuwait Group and the Dammam limestone aquifers. Most of the groundwater used in the State of Kuwait is for irrigation, some part of it is used for domestic purposes and for small scale industries. Since rainfall is seasonal and is less than the annual evaporation, the recharge from rainfall is negligible. Water levels in both the aquifers are highly affected by the pumping rate from each well. The groundwater is extracted heavily resulting in decline of water levels and the deterioration of groundwater quality though there is underflow from Saudi Arabia. Improvement of the groundwater management is essential for maintaining long-term productivity of the aquifers in the State of Kuwait.     

The Yellow River Basin: Water Accounting,Water Accounts,and Current Issues

Abstract

There is increasing recognition of the problems facing China in meeting the growing water demand in the Yellow River basin, the “cradle of Chinese Civilization” and a critically important agricultural and industrial region. Meaningful debate on the range and relative costs of options available to policy-makers in addressing the problem depend fundamentally on an accurate understanding of basin water resources. Unfortunately, the ability of outsiders to participate in the de bate and for Chinese, with their long history of water management, to contribute to similar discussions elsewhere in the world is hindered to some extent by a lack of understanding of differences in water accounting systems and concepts. This paper attempts to address this problem by describing the water accounting system used in the Yellow River basin and elsewhere in China. The paper shows that the primary difference between water accounting methodologies in the Yellow River and those typically applied elsewhere is related to supply accounting in general and groundwater accounting in particular. Although not currently included in its water accounting system, Chinese concepts of environmental water use, when included, will also differ substantially from those familiar to outside researchers. In terms of actual Yellow River balances, the paper highlights the apparent declining trend in basin rainfall and runoff and the dramatic growth in industrial and domestic water use. Together declining supply and rising demand will increasingly cause policy-makers to face hard choices in assessing their water planning options. These choices will only become more difficult as managers in the Yellow River, as elsewhere in the world, try to incorporate ecological needs in the water accounting equation.     

Using Similarity Analyses to Scale Out Research Findings Across Andean Watershed Basins

Abstract

Strategic research in agriculture and natural resources carried out by international research centers is deemed a public good and should, sooner or later, be put into the hands of development, governmental and non-governmental organizations. However, this research is usually done at specific pilot sites; there is a greater need to know how representative those sites are in relation to the diversity of contexts in other locations. Such is the case with the Challenge Program on Water and Food (CPWF), a global initiative in water research promoted by the Consultative Group on International Agricultural Research (CGIAR), which is developing and implementing strategic research in nine basins located in the tropics of Africa, Asia and South America. Given that resources are not available to collect data from the whole of the region, pilot sites are needed. It is hoped that research outputs obtained in the selected pilot sites can be the basis for scaling out solutions to similar situations in neighbouring or adjacent areas in same or different basins.

In order to contribute to the scaling-out process, different classification methodologies were applied to determine how specific watershed basins are representative of larger areas. The Andean eco-region served as a case study but the methods can easily be applied in other regions. The spatial diversity of biophysical and social conditions across the Andes requires careful site selection. Two methods, a combination of Weight of Evidence (WofE) and Logistic Regression (LR) methods and Fast Cluster analysis, were used to determine the similarity of selected sites with those excluded. A 1-km study resolution covering most of the Andes eco-region included annual rainfall, elevation, length of growing period, land cover, roads and population density as the key variables. Results showed complementarities between the two methods in presenting a probability surface of similarity across the Andes and a clustering of similar sites inside and outside the pilot basins. The output information forms a strong basis for devising plans to scale out research findings from the pilot basins to the whole region.     

Multi-Reservoir System Optimization using Chlorophyll-<Emphasis Type="Italic">a</Emphasis> Trophic Indexes

The problem of managing water scarcity by resorting to complex interconnected multi-source water systems needs to utilize management optimization techniques analyzing aspects of water quantity and quality in a common strategy. In the southern regions of Mediterranean Europe, the greater part of water resources for supply systems are derived from artificial reservoirs and water systems can become quite complex since they interconnect several sources and demand centers, as indeed occurs in the Region of Sardinia (Italy). A simplified approach to the requirement to insert water quality aspects in the mathematical optimization model can be achieved by examining the trophic conditions of reservoirs. Trophic State Indexes (TSI) based on Carlson’s (1977) make it possible to insert quality constraints in the water management optimization model also considering complex multi-reservoir and multi-user systems. Model formalization and implementation by the optimization toolkit WARGI (Water Resource system optimization aided by Graphical Interface) (Sechi and Zuddas 2000; Manca et al. 2004; Salis et al. 2005) is illustrated in this paper. The usefulness of a mixed quantity–quality optimization approach has been confirmed by WARGI application to a real multi-reservoir water resources system in southern Sardinia. The optimization model remains computationally efficient dealing with this complex multi-reservoir system and the obtained results can be seen as a reference target in a subsequent simulation phase.     

Internal-corrosion inhibitors for pipelines in heat-supply systems carrying water with a high oxygen content

The reliability of heat-supply systems is determined primarily by internal corrosion of the pipelines. The concentration of oxygen in the water exerts a major influence on the corrosion. In systems with a standard oxygen content, OéDF-Zn is a highly effective corrosion inhibitor. However, there are systems in which the quality of deaeration of the make-up water of the heat-supply system is low (or deaeration is nonexistent), and the concentration of oxygen is considerably above the standard value. Classed among these systems, for example, are the HWS systems, which are incorporated into closed heat-supply systems. The oxygen concentration in these systems is analyzed to assess the situation. __________ Translated from élektricheskie Stantsii, No. 6, June 2007, pp. 35–39.     

黄河三角洲河口地区土地利用及生态环境景观分析

通过人机交互解译1996年和2004年TM影像得到2期土地利用数据,求得到土地利用转移矩阵和各种生态环境景观指数。通过分析两期土地利用及景观结构指数之间的差异性,指出由自然和人为原因引起的生态环境的变化:研究区总面积有所减少,盐碱地改良后用于了鱼虾养殖,部分未利用地和水域盐碱化,区域景观类型丰富且均匀,局部破碎严重。