澜沧江流域大坝安全综合信息管理系统实现

介绍了澜沧江流域大坝安全综合信息系统的结构、组成和系统功能,对系统的结构进行深入地分析,着重对系统实现的重点部分(分布式的架构和数据中心集成方法)进行了阐述,还介绍了系统的高级应用(监测数据处理、工程安全评估、事故应急处理和信息报送等),就综合信息发布网站的结构和特点进行描述。该系统实现了澜沧江流域内多个大坝工程安全信息集中共享,降低了管理成本,具有良好的管理效益和实现价值。     

分布式光纤技术在锦屏一级水电站地质平硐边坡监测中的应用研究

应用分布式光纤传感技术对锦屏一级水电站地质平硐裂缝进行了监测分析,介绍了分布式光纤在工程平硐裂缝监测的布设和埋设工艺.采用组合式光纤方法实现了多量程、高精度的实时监测.通过与常规监测仪器结果的对比分析,结果表明,分布式光纤在裂缝监测方面具有较好的效果和实用价值.     

基于分类树的长距离引水工程多源数据管理系统设计

针对目前长距离引水工程在运行管理过程中存在的监测和检测数据异构、数据种类繁多、管理不规范、效率低下等问题,通过对多源数据种类及获取方式进行分析,构建了基于分类树的数据管理体系,并结合数据库技术,对数据库表结构进行设计,实现对多源数据的优化分类管理。基于此设计了基于B/S架构的长距离引水工程运行期多源数据管理系统,该系统严格按照数据管理体系进行设计,层次明确、结构严谨,方便了系统用户对数据进行统一、高效的管理,为引水工程运行期多源数据管理提供了一种新的解决方法。目前该系统已在某引水工程中投入使用,运行效果良好。     

计算机监控系统中的分布式实时数据库管理系统

分布式实时数据库管理系统是分布式计算机监控系统的核心，本文介绍了一种工于开放式计算机系统全分布式实时数据库管理系统的设计和实现。     

船闸计算机监控技术探讨

通过介绍船闸计算机监控技术发展,对基于高性能PLC、PC工作站和网络的监控系统进行简要设计,探讨了分布式监控系统中与计算机、控制、网络相关技术工程解决方案,提出了采用融计算机控制、分布式数据管理、大型异构网络为一体,在关键部位采用冗余设计的分层分布式计算机监控系统,是船闸计算机监控技术发展方向。     

分布式光纤测温远程控制在溪洛渡大坝中的应用

当采用多台分布式光纤测温主机对混凝土坝多坝段进行实时在线温度监测时,若人工提取测温主机的监测数据,势必削弱分布式光纤测温主机在线测温和实时监测的优势。对多坝段、多台分布式光纤测温主机远程控制系统进行了研究,结合建设中的溪洛渡特高拱坝,采用VB开发平台上的Winsock和Timer控件,将3台测温主机与服务器连接起来构成小型局域网,初步实现了分布式光纤测温远程控制。工程实践表明,该系统可以满足在测温过程中数据的实时采集及监控,为混凝土坝温度的光纤实时在线监测提供了有利的技术保证。     

工程水文数据库EHDBMS管理系统设计与实现

本文介绍了工程水文数据库EHDBMS管理系统的设计思想和设计技巧,较好地解决了数据结构复杂、检索条件多的管理信息系统研制的难题,并提出了一些实用的新方法,对管理信息系统的理论和实践的发展提供了一定的借鉴。运行表明,系统能满足各项工程水文数据I/O操作的要求,对水文数据自动化处理的实现、水资源的合理利用,提供了一个好的环境条件。     

堤防工程信息管理与风险评价系统的研究与开发

基于地理信息系统(GIS)和网络技术(Web),研究和开发分布式堤防管理系统,综合系统包括堤防信息查询子系统、堤防工程结构风险分析子系统、洪水风险子系统。系统可以方便地对堤防及保护区的各类信息进行查询,同时还可以根据历史大洪水或实时水雨情,对堤防的结构风险、洪水风险进行评估,成果数据可在C/S和B/S两种方式下进行查询、统计及展示等。     

洪家渡工程管理系统介绍

贵州乌江水电开发有限责任公司为更好的管理洪家渡工程的建设 ,从中国长江三峡工程开发总公司引进了工程管理系统。本文重点对这套管理系统的功能结构和目前在洪家渡工程中的应用进行介绍。     

EMS高级应用软件的开发及应用

介绍一个分布式能量管理系统(RD—800B EMS)中的高级应用软件的技术特点，包括高级应用 软件的构成及相互关系、采用的算法和技术、工程应用的效果与经验等。     

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。     

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。     

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.