遵循IEC 61850标准的广域电流差动保护IED

应用多点信息的广域继电保护已经成为当前继电保护领域研究的热点，IEC 61850系列标准的颁布使广域继电保护应用于现场成为可能。文中以广域电流差动保护智能电子设备（IED）为例，借鉴IEC 61850功能分层结构、统一对象建模和抽象通信服务接口的特点，对其进行了建模，扩展了广域电流差动保护新逻辑节点，实现了各IED之间的互操作性。对广域电流差动保护IED的硬件实现进行了设计，采用插件式的硬件构成，阐述了逻辑设备与硬件插件间的一一映射关系。     

一种改进的SCL系统配置工具

变电站配置描述语言（SCL）已经成为不同制造厂商的配置工具间相互交换信息的标准。通过对SCL对象模型及其变电站拓扑图形显示、SCL与公共信息模型（CIM）语义信息模型的协调等问题的研究,对SCL系统配置器的原有功能进行扩充,设计了一个改进的SCL系统配置工具,具备SCL文档的导入/导出、图形化的编辑、SCL对象模型、可缩放矢量图形（SVG）和CIM/可扩展置标语言（XML）文件的生成等功能。针对110 kV变电站的某线路间隔及智能电子设备（IED）,给出了一个SCL文档的实例,可以看出采用SCL配置工具可方便地实现对变电站及其IED的配置和管理。     

兼容IEC 61850的间隔层IED模型设计与实现

实现智能电子设备（IED）间互操作是变电站通信网络和系统系列标准IEC 61850的重要目标，模型设计是实现这一目标的重要步骤。从互操作性支持条件分析出发，给出了IED模型通用设计方法，讨论了间隔层IED的模型实现。间隔层IED的信息模型以数据结构的形式实现。从互操作性角度分析了已有数据逻辑结构的优缺点，提出了抽象通信服务接口（ACSI）-功能约束（FC）结构，把FC引入数据结构且真实反映了信息模型的对象层次，从而更好地支持互操作性。另外，提出了基于二叉树形式的二叉和三叉链表数据存储结构，通过例子验证了这2种结构的数据查找和遍历的便利性，并给出了ACSI-FC结构在二叉或三叉链表存储结构下的FC过滤方法。     

基于口令的变电站数据与通信安全认证

依据电力系统数据与通信安全标准IEC 62351，研究既能满足认证安全需求，又能保证最小的计算和传输开销，基于口令的变电站数据与通信安全认证方法。比较了几种国际上先进的安全口令技术，分析了IEC 61850标准中智能电子设备（IED）访问安全模型，提出采用安全远程口令（SRP）协议实现IED访问应用关联时的安全认证。最后，以变电站自动化IED间的身份鉴别为例，介绍了SRP协议的改进方法和具体的认证过程。研究结果对在变电站自动化系统中实施 IEC 62351标准具有参考意义。     

基于IEC 61850的保护功能交互模型

为了更好地实现基于IEC 61850的分布式功能的标准化设计、促进系统的工程实施，需要对保护功能在智能电子设备（IED）之间、IED内部逻辑节点（LN）之间的交互关系进行严谨的描述。文中为IED的交互过程构建了一个较统一的功能模型，阐述IED之间、IED内部LN之间的交互类型，采用扩展协作图和时序图分别刻画分布式保护功能下各LN之间的协作和时序关系，设计了IED的软件结构，为互操作测试实验提供了一定的参考。     

基于IEC 61850标准的新型集中式IED

基于IEC 61850标准的变电站自动化是一种必然趋势。站级总线、过程总线的应用对间隔层智能电子设备（IED）网络接口的实时性、可靠性有很高要求，且数量众多的间隔层IED使变电站网络接线复杂。计算机技术的快速发展使硬件的集成度越来越高，可靠性大幅度提升，间隔层设备将会向集成一体化方向发展，使设计理念为面向变电站整体功能，有利于控制、保护功能的协调并大幅度减少IED数量。提出了一种遵循IEC 61850标准的间隔层新型集中式IED方案，在1台新型集中式IED上实现多台IED所完成的功能，分析研究了其硬件方案、软件结构及内部信息交换方式等关键技术，为实施基于IEC 61850标准的变电站自动化系统提供了一种新的解决方案。     

继电保护的可靠性(上)

本文研究了电力系统继电保护可靠性问题的研究方法和研究范围的划分问题。提出应将继电保护可靠性问题的研究明确地划分为保护装置的可靠性设计、保护装置制造过程的可靠性管理、继电保护系统的可靠性设计、继电保护运行维护中的可靠性四个方面。每个方面应有自己的可靠性度量和计算方法。文中对这四个问题进行了研究的论述。还针对继电保护可靠性研究的需要，简要地介绍了可靠性理论的基本概念、定义和有关内容。     

IEC 61850标准一致性测试的方案和现场应用

介绍了一致性测试仿真环境的基本构成，包括智能电子装置（IED）服务器端模拟器、客户端监控软件、系统配置工具、IED配置工具和协议分析工具。在分析现场测试需求的基础上，提出了实现变电站内IEC 61850标准一致性测试的总体方案。应用IEC 61850标准一致性测试与仿真培训系统，针对西安供电公司2个110 kV变电站进行了完整的测试。通过分析和研究测试结果，验证了变电站支持的IEC 61850功能，对数据模型等存在的问题进行了探讨。     

变电站自动化信息交换安全认证体系

分析了基于IEC 61850体系的变电站自动化信息交换体系结构，基于数字证书和代理多重签名体制，提出一种实用与发展并重的变电站自动化信息交换安全认证体系。在变电站智能电子设备（IED）或变电站通信控制器中集成密码计算模块，采用普通的或代理的数字签名模式，实现信息交换过程中控制中心与变电站IED身份和信息完整性的认证。该安全认证体系符合IEC 61850标准体系，密码计算采用国家密码管理委员会办公室指定的密码技术。     

工作流建模分析:WF_Net、pi演算、WM_semantics

利用实例分析基于工作流网WF_Net,pi演算和工作流管理语义网WM_semantics在工作流建模过程中的优缺点,指出将以上建模理论的各自优势互相补充、合理整合,开发有效的过程建模理论,并将其应用于工作流过程模型的描述和分析是一种可行的方法。     

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。     

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.     

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。     

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.     

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。     

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.     

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.     

浙江省水域调查录入系统的设计和应用

浙江省水域调查录入系统将调查数据与电子地图相整合,对分类水域数据进行统计计算,并对输入数据进行合理性和完整性检查,得到调查范围内现有水域的详细数据,实现了水域调查数据输入、计算、统计和查询的数字化管理,提高了工作效率和工作质量,为各地下阶段水域保护规划编制和水域管理工作提供了数据支持。对该系统的设计原则、功能和技术设计等作了介绍。     

基于CT-连续加荷水泥乳化沥青混凝土细观损伤规律研究

利用CT技术对水泥乳化沥青混凝土的细观损伤过程进行实时扫描观测,获得了混凝土试件在连续加荷下的CT图像。通过采用直观分析法、CT数分析法、CT数与损伤变量关系3种方法分析表明,水泥乳化沥青混凝土的破坏过程可分为压密、扩容、裂纹扩展、破坏4个阶段,同时混凝土在受压过程中具有韧性,在极限荷载之前各断面处于压密和微扩容的强化阶段,极限荷载之后混凝土从损伤到破坏发展比较平稳。