配电网馈线末端故障定位优化算法

提出了一种能解决配电网馈线末端故障定位、并适用于多电源复杂网络故障定位的优化算法。根据网络拓扑结构和假定的正方向建立网络描述矩阵，由馈线终端单元（FTU）获得的故障过电流及其方向信息组成信息矩阵，结合网络描述矩阵对信息矩阵进行修正得到信息判断矩阵，由信息判断矩阵可以直接判别出故障区域。     

基于最短路的复杂配电网可靠性评估分块算法

配电网具有闭环设计、开环运行、网络中配置的开关相对较少的特点。基于该特点，应用最短路方法和分块技术提出大规模复杂配电网可靠性评估算法。给出配电网馈线末端节点、边界节点的定义以及块的定义和性质。基于最短路提出配电网分块形成算法，进而提出配电网可靠性评估算法。故障模拟时，文中方法以“块”为单位代替常规方法以“元件”为单位进行分析，利用最短路法确定开关元件的影响范围，节省了大量重复的开关元件搜索时间。应用该算法对RBTS及大量实际工程系统进行了可靠性评估，算例表明该算法具有高效性和工程实用性。     

网络拓扑着色算法在电力系统中的应用

电力系统中传统意义上的网络拓扑着色是指确定网络元件的带电状态， 并在图上以不同的颜色表示。文中重 新定义了网络拓扑着色算法，先确定网络元件的带电状态，再确定带电支路的连通状态是环路、桥路，还是 辐射支路，在确定支路的连通状态时利用DFS子轨迹的概念来简化计算，降低计算量。该算法可用于检查远 动系统中的遥信错误；也可用于确定调度操作对网络解列和负荷减载的影响，辅助调度员分析和决策。已在 一些网调、省调和地调EMS中的应用证明了该方法正确、有效。     

配电网拓扑结构概念聚类及其在优化规划中的应用

聚类分析是一种无监督的机器学习方法，被广泛应用于各研究领域。在城市配电网优化规划的研究中，现有的关于网络拓扑结构分析的一些方法并不适用于配电网优化规划工作，而关于配电网拓扑结构聚类分析的研究更是鲜见报道。基于对配电网结构、运行特点以及优化规划工作实际需要的认知，提出了一种结合模糊逻辑的配电网拓扑结构概念聚类方法，对于推进配电网优化规划问题的研究具有广泛的实际意义。为检验该方法的有效性，在该方法的基础上引入几个简单的概念，构成一个基本的机器学习模块，该模块可以方便地“嵌入”基于Agent行为和范例学习的新型遗传算法中，以提高原算法的计算性能。并用算例证明了在引入基于配电网拓扑结构概念聚类的机器学习模块后，新型遗传算法具有更高的计算效率和求解质量。     

10 kV中压配电网应用电力空间负荷密度特性研究

针对传统方法在研究水电配电网电力空间负荷密度的特性时存在电力负荷密度预测精度较低、用电高峰期出现供电紧张、运行稳定性较弱、安全性较低等问题,提出一种基于DLBAN模型的电力空间负荷密度预测方法。利用跨小波空间算法对水电配电网电力扰动信号进行去噪,获取电力空间滤波信号,根据DLBAN构建电力空间负荷预测模型,对待测区块指定最合适的类标签进行修正。利用DLBAN预测模型完成配电网电力空间负荷密度预测,得到其属性呈正相关性,从而实现对水电配电网电力空间负荷密度特性研究。结果表明,在水电配电网的应用中,城市第二产业的负荷密度的稳定性较强;不同用户的休息时间与负荷密度具有较强的关联性;第三产业的用电时间具有周期性,且负荷密度较大,对整个水电配电网区域负荷密度的贡献度较大,且具有较高的预测精度。     

基于GIS构建配电网拓扑关系的方法

配电管理系统所需的静态数据通常以地理信息系统(GIS)空间数据为来源，但由于GIS空间数据模型的局限性，以及电力系统的拓扑描述方式与通常意义上的GIS对拓扑关系的描述方式不一致，当前GIS不能提供满足配电网应用所需要的网络拓扑。文中结合扬州供电局配电网GIS项目，在分析GIS数据模型和配电网电气逻辑模型特点的基础上，根据配电GIS的数据管理方式和配电网应用对于电网拓扑数据的具体需求，详细阐述了如何基于GIS空间数据构建满足配电管理应用所需的拓扑关系，并给出了具体的数据结构和实现方法。     

基于混合微分演化算法的配电网架结构智能规划

应用地理信息系统（GIS）和改进的微分演化（DE）算法组成混合微分演化（GDE）算法来进行配电网架结构的智能规划。该算法首先利用配电网络的地理特征，分阶段过滤明显不适合的线路，得到初步规划网络，随后利用DE算法收敛快速、鲁棒性强的特点，将其应用到优化计算中。为避免早熟，对传统DE算法进行了改进，利用解群转移策略在给定的条件下对解群进行分散处理，以跳出局部最优点，得到全局最优解。并给出了某省会城市的城区高压配电网规划算例。     

配电网中容量电费定价方法

在传统的配电网容量电费的电价中，只考虑了用户的容量大小，而没有考虑用户的功率因素、用户对供电的可靠性要求以及用户的具体位置等用户属性。通过对配电网用户属性的分析，提出了一种用模糊聚类的方法对配电网内不同性质的用户进行分类的方法，并依照此分类将配电网中的容量费用按一定的权重在不同类别的用户间进行分配。此全新的容量电费电价方法，较全面地考虑了用户容量大小、用户的具体位置、用户的功率因数、用户对供电的可靠性要求等因素，避免了将配电网内的投资费用仅按容量进行分摊的局限性，使配电网内的投资费用的分摊趋于合理。实例研究表明，该容量电费的定价方法能更合理地反映用户的属性。     

基于GIS的农村配电网线损管理系统的研究

配电网网损计算作为DMS的高级分析功能之一,在配电网规划和提高配电系统运行经济性方面起着重要的作用。本文阐述了配电GIS的研究现状以及基于GIS的网络拓扑分析方法,在此基础上完成了农村配电网线损管理系统的数据库设计、功能模块设计及最终实现。     

配电网模糊优化规划(Ⅰ)——模型与方法

配电网规划的特点和难点是不确定性的处理，以往对配电网规划不确定性的研究大多是对某一步骤进行。文中应用模糊数学理论，形成了贯通的配电网模糊规划方法。可以考虑负荷、投资、电价等相关因素的不确定性，建立相应的模糊优化规划数学模型。结合配电网的特点，提出了配电网的模糊负荷预测方法、模糊潮流算法和模糊优化方法。采用L-R型模糊数进行负荷预测和潮流计算，提出了简便实用的边界法，即用负荷模糊预报值的左、右边界和中心值分别进行潮流计算，再综合计算结果。这在输电网的模糊潮流计算中是不可行的，但配电网的辐射状结构决定了这种模糊潮流算法的简单性，可以满足模糊规划的需要。算例表明，模糊规划方法可以得到鲁棒性强的规划方案。     

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。     

Serial discontinuities in a Rocky mountain river. I. Distribution and abundance of plecoptera

Samples were taken year-round at eleven sites along the altitudinal profile (2900-1400 m a.s.l.) of the Gunnison River, a 329 km tributary of the Colorado River, to document the distribution of the Plecoptera and to evaluate responses to hypolimnial-release dams in the headwaters and middle reaches. Twenty-two species were present, with the greatest species richness occurring in an unregulated segment upstream of the middle reach dams; average nymphal biomass over the study period (175 organisms, 395 mg dry mass m^?2) was also greatest in this segment. Only four species (58 organisms, 48 mg m^?2) were present in the tailwaters of the headwater dam and values were greatly reduced (nine species; 35 organisms, 180 mg m^?2) below the middle reach dams. The stonefly community recovered ca. 80 km downstream from the last dam (15 species; 244 organisms, 250 mg m^?2), apparently in response to natural resetting of environmental conditions corresponding to those above the middle reach dams. At the most downstream site (11) only four species (four organisms, 16 mg m^?2) were present. The observed distributional pattern is a classic serial discontinuity in response to hypolimnial stream regulation in a temperate latitude river.     

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.     

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。     

Automated system for removal and pneumatic transport of fly ash from electric precipitator hoppers

A system for removal and pneumatic transport of fly ash is examined, in which air pulses act on batches (pistons) of ash formed in a duct. Studies are made of the effect of several physical parameters on the force required to displace a piston of ash and these serve as a basis for choosing a system for removal and pneumatic transport of ash simultaneously from several hoppers of an electric precipitator. This makes it possible to separate the ash particles according to size without introducing additional components. Formulas are given for calculating the structural and dynamic parameters of this system and measurements of indirect dynamic parameters are used to calculate the input-output characteristics of the system. In order to optimize the system, configurations for summing several ducts into a single transport duct for pneumatic ash transport are proposed. Some variants of dry ash utilization and the advantages of producing of size-separated particles are considered. __________ Translated from élektricheskie Stantsii, No. 2, pp. 26–30 (2008).     

The flood pulse advantage and the restoration of river-floodplain systems

The ‘flood pulse advantage’ is the amount by which fish yield per unit mean water area is increased by a natural, predictable flood pulse. Evidence for this increase is presented from tropical and temperate fisheries. It is argued that increasing multispecies fish yield by restoring the natural hydrological regime is consistent with increasing production of other trophic levels and with restoration from ecological and aesthetic viewpoints. When applied to a river-floodplain system, this restoration would provide a large, self-sustaining potential for recreation, commercial exploitation, and flood control. An interim ‘natural flood pulse’ restoration approach is proposed for systems modified for navigation. This approach approximates the natural hydrological regime in a river reach and is intended as a first step in the long process of restoring the watershed.     

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。