一种用于统一OMS与PMS设备库的BSM结构设计

提出了一种能用于统一电网调度运行管理系统（OMS）和电网生产管理系统（PMS）基础设备库的桥式对称模型（BSM）结构设计。阐述了BSM结构中的逻辑设备和物理设备的解耦、逻辑设备与物理设备的桥接以及BSM结构中运行位置、抽象物理设备在统一OMS和PMS设备库方面的核心作用。通过BSM中的桥，采用继承技术分别在OMS和PMS中派生出对称的具体设备类型，满足OMS和PMS对于设备管理的不同需要。利用BSM结构设计，在实现OMS和PMS设备库结构统一的同时，最终实现这2个系统设备库的集成。     

高压电缆T型接头在铁山~仙公庙110kV线路工程中的应用

该文结合铁山~仙公庙(双T西郊)110 kV线路工程,探讨采用高压电缆T型接头,解决高压电缆线路的T接问题。文中进行了电缆T型接头与架空线路T接方案比较,分析了高压电缆T型接头接地方式和运行可靠性与局限性,结果表明,应用电缆T型接头大幅度缩小了线路T接点的占地面积,实现了小型化;此外,为提高供电可靠性,文中建议在新建电缆T型接头中通过无源植入技术,对线芯温度进行直接接触式测量,对接地系统的环流和感应电压进行数据采集,以及电磁场分布情况监测,为今后在更高电压的电缆T型接头设计制作提供数据参考。     

山西省定襄县农村水电直供电片区电网改造规划

定襄县水电直供电片区电网建设年代久远,线路老化,配电设备落后,损耗高,已不能满足日益增长的供电负荷及供电质量的要求。依据《水利部关于编制农村水电直供电片区电网改造规划的通知》,对直供电片区电网现状进行了分析,提出了重点改造方案,按照3年完成电网改造的设想,将电网进行合理改造,更新设备、优化路径,重新依据负荷要求对配电系统进行升级,根据近期负荷量和发电量的变化,预测电网发展。     

双端测距中的自适应线路参数在线估计

提出了一种线路参数在线（自适应）估计方法，取线路长度为线路杆塔间的水平距离，而把各种因素对线路参数的影响统一归入线路参数的变化，借助双端（或多端）通信工具，自适应半实时在线估计线路参数。在双端测距中，利用已有的硬件设备，可以有效地削弱线路参数变化对测距精度的影响。该方法对于各种架空输电线路，尤其是对于穿越地形复杂、气候恶劣地区（如高寒覆冰地区）输电线路的双端测距具有较重要意义。     

电网实行接网费和过网费探讨

本文简要介绍了英国电网实行接网费和电网使用费的情况，结合我国国情提出了电网接网费、过网费的定义及过网费在电厂和供电公司的分配方法，分析了接网费、过网费与各种电价之间的关系，以及实施接网费、过网费对电力系统资源优化配置和建立电网投资费用正常回收渠道的作用     

长白电网黑启动方案浅析

长白电网是以水利发电为主的小水电电网,与国网只有1条线路连接,连接薄弱,可靠性低,是典型的单电源辐射型网络。在国网发生故障,短时不能恢复供电时,积极发挥水轮机组启动迅速、操作便捷的优势,尽快恢复对本地区供电,减少对工农业生产、居民生活的影响和损失。     

三维GIS技术在输电线路状态监测中的研究与应用

实施输电线路状态在线监测是保证线路安全、可靠供电主要措施之一,文章介绍了输电线路状态在线监测系统的建设方法,应用三维GIS技术实现了线路走廊可视化,并且应用模型简化技术、渐进式编码与流传输技术、空间粒子系统技术等实现了监测设备和监测数据的三维可视化,最后提出了在线监测数据的空间分析模型。     

一种特殊运行方式下的保护配置方案研究

1概述随着温州电网负荷的日益增长,加上负荷分布的不均匀,部分主变压器、110 k V线路容量不足,设备容量成为主要的供电瓶颈。特别是在某些设备改造过程中,特殊的电网运行方式就更加不可避免。特殊的电网运行方式在提高供电能力的同时,一定程度上也降低了电网供电的可靠性,增加了调     

浅谈千阳县小型水电站并网后无功不足

地方小水电站因受电网电压波动影响,上网时无功不足现象时有发生,这种现象不但降低用电设备效率,也降低电气设备使用寿命,直接关系到电网供电质量.本文通过介绍千阳县寇家河小水电现状,分析其并入电网后无功出力不足原因,并就采用何种措施进行补救提出了自己看法,旨在降损节能、提高效率和提高电网供电质量以及供电电压水平.     

全国电网互联的枢纽——华中区域电网

据《中国电业》特约撰稿陈也清有关文章中反映的情况，华中区域电网地处中国腹地，覆盖面积130万km^2,供电人口3．8亿，是我国供电人口最多的区域电网。截至2002年底，华中五省一市发电装机容量达到7151万kW，约占全国总装机容量的20％。目前，华中电网已发展成为以500kV线路为骨干网架、以220kV线路为主体，北与华北电网相联、东与华东电网相通、南将与南方电网联网、西将与西北电网连接的大电网，从而真正成为“西电东送，南北互供，全国电网互联”的枢纽。     

Call for Papers

正As the eldest and most distributed professional journal of water industry,Water Wastewater Engineering(W WE)gained very wide acceptance from the colleagues working in this field in this country since start publication in 1964.Now it is administrated by the Ministry of Construction of the People’s Republic of China and sponsored by the China Civil Engineering Society etc.     

地下厂房施工过程的三维非线性数值模拟分析

根据冗各电站地下厂房开挖支护的施工顺序,以隐式杆单元模拟锚杆,以壳单元模拟混凝土喷层,采用三维非线性有限元技术,对洞室群的开挖支护动态过程进行了模拟计算。通过三维非线性有限元计算分析得到:洞室群动态开挖过程中围岩应力变形的分布规律,围岩塑性区的发展规律,锚杆受力变化情况。计算结果表明:整个开挖过程中,洞周围岩位移变化规律正常,量值较小,塑性区主要分布在洞室周边,围岩稳定性较好;但在洞室交叉口处围岩的变形较大,出现较大范围的塑性区,在此基础上提出了支护措施优化方案,并对优化方案的效果进行了评价。     

Evaluation of freshwater mussel relocation as a conservation and management strategy

The relocation of unionacean mussels is commonly used as a conservation and management tool in large rivers and streams. Relocation has been used to recolonize areas where mussel populations have been eliminated by prior pollution events, to remove mussels from construction zones and to re-establish populations of endangered species. More recently, relocation has been used to protect native freshwater mussels from colonization by the exotic zebra mussel Dreissena polymorpha. We conducted a literature review of mussel relocations and evaluated their relative success as a conservation and management strategy. We found that 43% of all relocations were conducted because of construction projects that were forced to comply with the Endangered Species Act 1973 and that only 16% were monitored for five or more consecutive years. Most (43%) relocation projects were conducted from July to September, presumably a period when reproductive stress is relatively low for most species and the metabolic rate is sufficient for reburrowing in the substrate. The mortality of relocated mussels was unreported in 27% of projects; reported mortality varied widely among projects and species and was difficult to assess. The mean mortality of relocated mussels was 49% based on an average recovery rate of 43%. There is little guidance on the methods for relocation or for monitoring the subsequent long-term status of relocated mussels. Based on this evaluation, research is needed to develop criteria for selecting a suitable relocation site and to establish appropriate methods and guidelines for conducting relocation projects.     

基于模型试验的河床砂砾石层基本特性研究

为了经济可靠地确定深厚覆盖层的基本特性参数,以大渡河双江口水电站坝基河床砂砾石层基本特性研究为工程背景,进行大尺寸模型试验,研究河床砂砾石层的旁压模量和动探击数随密度、级配以及上覆压力的变化规律。根据室内模型试验结果,结合现场旁压试验及钻孔试验成果,推断出坝址区河床砂砾石相关层位的密度,并依此进行砂砾石室内力学试验,获得设计所需力学参数。研究成果可为深厚覆盖层基本特性测试提供新的方法。     

库水波动下库岸边坡地下水浸润线解析解及误差分析

解析法是库岸边坡地下水浸润线计算中便于实际应用的方法,但该方法须基于若干假定并对潜水运动基本方程线性化后才能求解。针对各假定和线性化过程建立不同的地下水渗流数学模型,用解析法和有限元法解答上述数学模型,分析各误差大小及其规律。结果表明：库岸垂直处理带来的误差要小于方程线性化处理和不考虑非饱和渗流带来的误差,而且它们都随渗透系数变大而减小;在三峡库区库水调度情况下,假定库水位等速变化带来的误差对大多岸坡而言可以忽略;计算库岸边坡地下水浸润线时,解析法只适用于水位变化幅度相比含水层厚度较小,且几何边界规则、岩土结构简单、岩土体渗透性较好时的情况。     

SPATIAL AND TEMPORAL WATER QUALITY VARIABILITY IN AQUATIC HABITATS OF A CULTIVATED FLOODPLAIN

The floodplains of lowland rivers contain diverse aquatic habitats that provide valuable ecosystem services but are perturbed when intensively cultivated. Hydrologic, water chemistry and biological (fish) conditions in five aquatic habitats along the Coldwater River, Mississippi, were measured for more than 4 years: the river, two severed meanders that functioned as backwaters, a managed wetland and an ephemeral channel draining cultivated fields. Off‐channel habitats were connected to downstream regions 0.10% to 32% of the dry season and 24% to 67% of the wet season. The median temperatures for the five monitored sites ranged from 18°C to 23°C, the median total solids concentration for all sites was 135 mg L^?1, the median total phosphorus was 0.29 mg L^?1 and the median total nitrogen was 1.56 mg L^?1. Chemical and physical water quality displayed strong seasonal differences between the wet winter/spring and the dry summer/fall periods so that temporal variation consisted of gradual seasonal trends superimposed on strong diurnal variations. All off‐channel habitats exhibited periods of hypoxia and temperatures >30°C during the dry season. Between‐site gradients of water and habitat quality were strongly coupled to water depth and runoff loading. The rehabilitation of one backwater by increasing water depth and diverting agricultural runoff was associated with improved water quality and fish species richness relative to an adjacent untreated backwater. The diversion of polluted runoff and the use of water control structures to maintain greater water depth were observed to be effective management tools, but the former reduces the water supply to habitats that tend to dry up and the latter reduces connectivity. Published in 2011 by John Wiley & Sons, Ltd.     

Changes in Summer Irrigated Crop Area and Water Use in Southeastern Turkey from 1993 to 2002: Implications for Current and Future Water Resources

Changes in summer irrigated cropland acreage and related water use are estimated from satellite remote sensing and ancillary data in semi-arid Southeastern Turkey where traditionally dry agricultural lands are being rapidly transformed into irrigated fields with the help of water from the Euphrates-Tigris Rivers. An image classification methodology based on thresholding of Landsat NDVI images from the peak summer period reveals that the total area of summer irrigated crops has increased three-fold (from 35,000 ha to over 100,000) in the Harran Plain between 1993 and 2002. Coupled analysis of annual irrigated crop area from remote sensing and potential evapotranspiration based estimates of irrigation water requirements for cotton indicate a corresponding increase in agricultural water use from about 370 million cubic meters to over one billion cubic meters, a volume in accordance with the state estimates. These estimates have important implications for understanding the rapid changes in current agricultural withdrawals in Southeastern Turkey and form a quantitative basis for exploring the changes in future water demands in the region. For example, expansion of irrigated lands have led to a steady decrease in potential evaporation due to increased roughness and decreased humidity deficit in the Harran Plain. Assuming that the changes in future evaporation conditions will be of similar nature, water use for irrigation is expected to decrease over 40 percent in future irrigation sites. Incorporating this decrease in overall planning of the irrigation projects currently under construction should lead to improved management, and by extension, sustainability of water resources in the region.     

基于BP神经网络-马尔科夫链模型的隧道围岩位移预测

在隧道工程施工中,围岩位移预测起着很重要的作用。将BP神经网络-马尔科夫链模型引入到隧道围岩位移预测中来,通过对训练样本的学习,利用BP神经网络实现了对位移时间序列的滚动预测,同时得到了实测值与预测值的相对误差;在此基础上利用马尔科夫链对相对误差进行修正,有效地提高了预测结果的精度。并将该模型应用于某公路隧道拱顶下沉位移时序预测中,结果表明该模型具有精度高、科学可靠的特点,为隧道围岩变形的预测提供了新的途径。     

Spatio‐temporal variation of gross CO2 and CH4 diffusive emissions from Australian reservoirs and natural aquatic ecosystems,and estimation of net reservoir emissions

Carbon dioxide (CO₂) and methane (CH₄) diffusive emissions were measured during two field surveys in Queensland and Tasmania, Australia, using the floating chamber method. Bubbling and degassing emissions in 2010 were estimated in Koombooloomba Dam reservoir using only inverted funnels and gas concentrations, respectively. A total of 14 reservoirs and 16 rivers and lakes were sampled from 2006 to 2010. Spatial variation was substantial within each water body, as well as between them. The main drivers of diffusive emission variation were physiographic region and climate, with a clear demarcation being observed between diffusive emissions from tropical Queensland and temperate Tasmania, and between the humid West Coast Range (Tasmania) and dry Central Plateau (Tasmania). Higher CO₂ and CH₄ diffusive emissions were observed during the dry season, when long water residence times would promote organic matter degradation. Estimated total gross emissions, including diffusive, bubbling and degassing emissions, for Koombooloomba Dam reservoir were about 1.5 × 10⁶ t CO₂eq km² per year, or 24 × 10⁶ t CO₂eq per year. This corresponds to a plant emission factor of 3.18 kg CO₂eq MWh^?1. Using an estimate of terrestrial emissions derived from literature data for the Tully River catchment area, rough estimated net emissions from the catchment area are about 44 kt CO₂eq per year, or 5.83 kg CO₂eq MWh^?1, which is in the lower range of the studied reservoirs.     

Short communication. Pipelines as a refuge for freshwater snails

In the lower River Murray, Australia, populations of gastropods have declined markedly over the past 40 years. Of the native fauna of about 18 species, only the ancylid Ferrissia petterdi remains common (but in patches), and another five species feature in sporadic local resurgences. Until recently the viviparid Notopala was thought to be extinct. The introduced physid Physa acuta is widespread, but in low numbers. The decline probably is associated with flow regulation, high turbidity and the introduction of common carp. Snail populations have persisted, however, in irrigation pipelines fed from the river, where they periodically cause blockages. This paper reports the discovery of the only known populaion of Notopala hanleyi in a pipeline where the inner wall accumulates microbial and other organic matter, providing high quality food for snails. In the Murray before regulation most of the periphytic biomass was probably microbial, as fluctuating water levels would have maintained littoral communities in a highly productive, early state of succession his postulated that, by stabilizing seasonal water levels, regulation has promoted the production of filamentous green algae, an inferior food source, and so displaced snail populations from the open aquatic environment.