Safety provision and an expert system for diagnosing and predicting dam behavior

Conclusions 1. An expert system is an efficient and flexible tool for taking decisions on a wide range of topics where other methods such as classical ones cannot be used. An expert system has many advantages as a tool for decisions; it is always to hand (this cannot be said of experts generally) and is not deflected by secondary details and sticks strictly to the deduction logic. In most practical cases, it provides decisions identical with those given by experts, or sometimes better than them. 2. The expert system for diagnosing and forecasting dam behavior to provide safety has been developed at this Institute and represents the first stage in the creation of the “Dam safety expert system”. That expert system can give information on the state of a structure and provide diagnosis and forecasts for it. Also, if necessary, an expert can engage in interaction with the system and obtain recommendations and assistance over rapid decisions. 3. The development and support of any expert system require the joint efforts of a large team of engineers and others. The system requires a certain architecture for the database and knowledge base, which in turn need management and the availability of means of accumulating and distributing data. A coordinating organ (brain center) is required throughout the existence of the system in order that it should be used successfully for resolving problems in hydraulic engineering. That brain center should not only organize the creation of the system but should also guide the realization of the project and organize the software, the analysis of accumulated knowledge, the systematization of terminology, quality control, and training the system, the staff, and the users. Revised version of a paper read at the International Conference on Reservoir Dams in Mexico in July 1998. Translated from Gidrotekhnicheskoe Stroitel’stvo, No. 6, pp. 22–26, June, 2000.     

Application of a model-based optimisation methodology for nutrient removing SBRs leads to falsification of the model.

Recently, a model-based optimisation methodology for SBR operation has been developed and an optimal operation scenario proposed to improve N and P removal in a pilot-scale SBR. In this study, this optimal operation scenario was implemented and evaluated. The results of the implementation showed that the SBR performance was improved by approximately 50 and 40% for total nitrogen and phosphorous removal, respectively, which was better than predicted by the model. However, the long-term SBR performance was found to be unstable, particularly owing to settling problems developed after the implementation. When confronted with reality, the model used for the optimisation of the operation was found to be invalid. The model was unable to predict the nitrite build-up provoked by the optimal operation scenario. These results imply that changing the operation of an SBR system using a model may significantly change the behaviour of the system beyond the (unknown) application domain of the model. This is simply because the mechanistic models currently do not cover all the aspects of activated sludge systems, e.g. settling and adaptation of the microbial community. To further improve model-application practices, expert knowledge (not contained in the models) can be valuable and should be incorporated into model-based process optimisations.     

Specialized prototype system of determination of technical state of electric plant equipment

Conclusion The writers have described some results of application of the method of structural invariants for solution of different management problems, including diagnosis of the technical state of elements of the electric equipment of electric plants. It is shown that the procedure for construction of the SFM of a management system can be extended to diagnosis problems, without substantial difficulties. Practical realization of the procedure — the DEXELEK prototype diagnosis expert system — confirmed its operation capacity and demonstrated quick action and sufficiently good service for the user in a prototype expert system. Development of dialogue characteristics of the system permits converting it into a commercial program product without changing the methodological bases of its construction.Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 3, pp. 32–37, March, 1995.     

Using the W&H integrated uncertainty analysis framework with non-initiated experts.

The W&H (Walker and Harremo?s) integrated uncertainty analysis framework was put forward with the aim of providing a conceptual basis for the systematic treatment of uncertainty in model-based decision support activities such as policy analysis, integrated assessment and risk assessment. It provides a heuristic tool that can be applied in decision support exercises to classify and report the various dimensions of uncertainty. The intention is to stimulate better communication among analysts as well as between them and policymakers and stakeholders. The framework successfully articulates diverse scholarly understandings of 'uncertainty', 'ignorance', and 'quality' in science for policy, Nevertheless, experience with the W&H framework has revealed that many of the concepts put forward are relatively unfamiliar--and perhaps somewhat controversial--to experts practising decision support. Thus, efforts are required to communicate the W&H framework to experts in such a way that their knowledge of uncertainty is elicited adequately, without them being overly intimidated or confused by the novelty of the concepts presented to them. After introducing the W&H conceptual framework, this paper presents the methodology that was used in applying the W&H framework in expert elicitations on uncertainty in the risk assessment of genetically modified crops. Experiences with the use of this methodology are discussed and recommendations for further improvement are given.     

龙羊峡大坝安全评价专家系统研制关键技术

从龙羊峡大坝安全监测的特点和要求出发，基于现代安全系统工程中的因果关系网络分析思想，提出了综合运用因果分析、面向对象知识表达、神经网络与元知识规划等技术的研制方案，成功地解决了大坝安全评价中监测信息的“组合爆作”和“搜索爆炸”问题．事实证明该方案取得了理想的效果．     

综论人工智能技术在大坝安全监控中的应用

人工智能技术经过从结构主义向功能主义、从硬件方法向软件方法的转变，在现代先进的计算机软硬件技术支持下，许多领域已取得了巨大的成功。综论了几种人工智能技术在大坝安全监控领域中的应用。数据开采是一门新兴智能技术，它的引入可解决大坝安全监控数据量大，知识面广，从而带来分析问题速度慢的困难；专家系统将专家知识编码成计算机能够识别的语言，将专家的经验和思维转化成先进合理的推理策略，为大坝安全评价提供专家级的技术支持；神经网络技术独特的结构和处理信息的方法，对解决大坝安全监控专家系统的“瓶颈”问题是一个很好的方法。     

船闸输水设计专家系统知识表示方法和知识库

介绍了船闸输水设计专家系统中的知识表示方法和知识库的组成。根据船闸输水设计的特点，选择面向对象的知识表示方法，描述了船闸输水系统的设计知识。由输水系统设计过程，确定了知识库的组成及内容。     

水文资料复审汇编查错专家系统的研制

总结水文资料复审汇编中存在的问题。结合专家系统的原理,给出水文资料复审汇编查错专家系统的设计思路和方法,根据专家的经验,构造知识库,讨论知识的获得、编码和存储。使用SQL SERVER数据库技术完成一个小型的专家系统原形,利用该原形系统对广东省2006年的水文整编资料进行审查,试验结果表明系统能够达到专家的水平。     

大坝安全监控专家系统中知识的获取与维护

知识库中知识的丰富程度直接影响着专家系统的智能水平，同时，知识库中知识的组织与存储模式将影响推理机的推理效率。文中着重论述了大坝安全监控专家系统知识库子系统中知识获取的设计与实现，以及知识维护的方法，使知识库具有较好的知识扩展性和合理性，专家系统具有较高的智能水平和较高效的推理性能。     

Numerical modeling of Reynolds scale effects for filling/emptying system of Panama Canal locks

Significant scale effects have been detected on the filling/emptying time measured with a reduced-scale physical model of the Third Set of Locks of the Panama Canal. During the design phase, corrections were made to compensate for these effects. However, the measurements at the prototype scale indicated that the corrections were insufficient because they only accounted for the differences in skin friction. In this study, a general methodology was proposed to evaluate scale effects using three-dimensional numerical models. This methodology was validated and then applied to a portion of the filling/emptying system of the Panama Canal to quantify its scale effects. The results showed that this technique can consider all sources of scale effects that affect head losses, such as skin friction and flow separation, and thereby correctly simulate the filling/emptying time at the prototype scale. The proposed methodology for scale effect quantification can be used to correct the results of physical models, and it can be expected to improve estimation of the performance of prototypes.     

How participatory can participatory modeling be? Degrees of influence of stakeholder and expert perspectives in six dimensions of participatory modeling.

The authors are involved in a project aiming at the development of a methodology for participatory modeling as a tool for public participation in water resource management. In this paper, some examples of different degrees of stakeholder influence in six key dimensions of participatory modeling are identified and discussed. Arnstein's (A ladder of citizen participation. Journal of the American Institute of Planners, 1969, 4, 216-224) critical discussion of different degrees of "real" decision-making power is taken as a point of departure to assess possible degrees of stakeholder influence. Can we as participatory modelers be sure that we are really inviting our research objects to an equal communicative relationship where local perspectives, knowledge and priorities are respected to the same extent as central and/or expert perspectives? This paper presents an approach that could be used as a tool for structured reflection to avoid unreflective tendencies towards expert knowledge dominance and low degree of stakeholders' real influence over the process.     

南通市现状水资源保障能力综合评价

以工程保障、社会经济保障、环境保障和效率保障作为南通市水资源保障能力现状评价的准则层,以缺水率、有效灌溉面积率、单位GDP用水等12个指标作为指标层构建了南通市水资源保障能力综合评价指标体系。采用层次分析法和专家评分法确定指标权重,通过加权平均确定综合评价值。评价结果为:南通市现状保障能力总体处于中等,从分类保障情况看,工程保障能力最好而环境保障能力最差;从各行政区的保障能力看,如皋市综合保障能力最好,而如东和海安县综合保障能力最差。最后对如何提高各地区水资源综合保障能力进行了一定讨论。     

Groundwater Allocation Using a Groundwater Level Response Management Method—Gnangara Groundwater System, Western Australia

The Gnangara groundwater system (Gnangara system) is an important source of groundwater for Perth, Western Australia: in the order of 350 GL of groundwater is abstracted annually. The Gnangara system also sustains groundwater dependent ecosystems (GDEs), mostly wetlands and native vegetation. Declining groundwater levels across the system have led to impacts on a number of key GDEs. Western Australia’s Department of Water recently prepared a Water Management Plan for the Gnangara system. Allocation limits were reviewed as part of the plan preparation. To assist in reviewing allocation limits, an adaptive Groundwater Level Response Management (GWLRM) methodology was developed and implemented. This paper describes the methodology and its application to the Gnangara system. The methodology was developed to be used as a corrective tool for the short- and medium-term, to assist in achieving long-term sustainability of groundwater management in the context of changing climate and declining groundwater levels. The GWLRM methodology is based on groundwater storage depletion and can be applied to existing allocation limits as an interim tool to assist in making management decisions aimed at recovering groundwater resources. The key to the GWRLM correction is that it will direct water allocation towards sustainable levels on the basis of measured trends. Allocations corrected through application of the GWRLM would therefore represent interim and improved water allocation figures. GWLRM can also identify potential problem areas where the principles or calculations used for long-term sustainable groundwater allocation would need to be reviewed. For the Gnangara system, the calculated storage changes or GWLRM corrections were considered together with results of predictive modelling as part of an expert panel process to derive a more sustainable interim groundwater allocation regime while further research is being completed.     

Public-Private Partnerships in the Water Sector

Abstract

Types of partnerships between public and private companies in water and sewage services are evaluated on the basis of the economic efficiency of the scheme for each partner. Modeling of public-private partnerships involves the formulation of a contract prototype, which determines the roles, functions, and responsibilities as well as the allocation of costs and revenues for each partner. Alternative water management scenarios are used to identify the investments required for meeting the projected demand for water and sewage services. Investment and operational costs as well as revenues from water and sewage services are estimated according to the allocation defined in the contract prototype. The economic efficiency of the scheme is assessed through a cost benefit analysis for each partner. The evaluation of different water management scenarios indicates that, for the Cyclades Islands, Greece, there is a substantial water market where several forms of partnerships could be attractive for both the public and the private sectors. Such partnerships include, among others, lease purchase, temporary privatization, built operate transfer (BOT), and built own operate transfer (BOOT). These forms of public-private partnerships could also be successful in similar regions where significant improvements and expansion of the infrastructure is required while access to the required funds and expertise is restricted for small public water companies.     

基于神经网络的专家系统实现研究

通过介绍了神经网络及专家系统，阐述了基于神经网络专家系统设计思想及系统结构的优缺点，并介绍了神经网络专家系统在大坝安全监测上的实现。     

Safety evaluation system for hydraulic metal structures based on knowledge engineering

A comprehensive safety evaluation system taking the most influential factors into account has been developed to evaluate the reliability of hydraulic metal structures. Applying the techniques of AI and DB, the idea of a one-machine and three-base system is proposed. The framework of the three-base system has been designed and the structural framework constructed in turn. A practical example is given to illustrate the process of using this system and it can be used for comparison and analysis purposes. The key technology of the system is its ability to reorganize and improve the expert system＇s knowledge base by establishing the expert system. This system utilizes the computer technology inference process, making safety evaluation conclusions more reasonable and applicable to the actual situation. The system is not only advanced, but also feasible, reliable, artificially intelligent, and has the capacity to constantly grow.     

大坝安全监测专家系统的理论及其应用

简述近年来开发的由推理机、知识库、方法库、数据库、图表库等组成的大坝安全专家系统的各部分内容和功能。重点阐述了知识库的组成、表示及其应用。对其余各库及推理机作了扼要总结，文末介绍该系统在工程中的应用情况，从反馈信息及结果可知，该系统能较好地实现大坝安全评判这种复杂的工程问题的求解，从本质上区别于信息管理和分析系统     

南方地区地下水功能评价指标筛选研究——以广东省为例

在分析南方地区地下水资源特点的基础上,综合运用理论分析法、专家咨询法和灰色关联度模型,构建地下水功能评价指标体系;以广东省为例探索地下水功能评价指标筛选方法和筛选程序,选择理论分析法和专家咨询法进行第1次指标筛选,选择灰色关联度进行第2次指标筛选。与北方地区地下水功能评价指标进行对比,分析指标的合理性,用得到的广东省地水水功能评价指标体系为依据进行评价,其结果与实际情况基本吻合。     

Evapotranspiration from an Olive Orchard using Remote Sensing-Based Dual Crop Coefficient Approach

A remote sensing-based approach to estimate actual evapotranspiration (ET) was tested in an area covered by olive trees and characterized by Mediterranean climate. The methodology is a modified version of the standard FAO-56 dual crop coefficient procedure, in which the crop potential transpiration, T _p, is obtained by directly applying the Penman-Monteith (PM) equation with actual canopy characteristics (i.e., leaf area index, albedo and canopy height) derived from optical remote sensing data. Due to the minimum requirement of in-situ ancillary inputs, the methodology is suitable also for applications on large areas where the use of tabled crop coefficient values become problematic, due to the need of corrections for specific crop parameters, i.e., percentage of ground cover, crop height, phenological cycles, etc. The methodology was applied using seven airborne remote sensing images acquired during spring-autumn 2008. The estimates based on PM approach always outperforms the ones obtained using simple crop coefficient constant values. Additionally, the comparison of simulated daily evapotranspiration and transpiration with the values observed by eddy correlation and sap flow techniques, respectively, shows a substantial agreement during both dry and wet days with an accuracy in the order of 0.5 and 0.3 mm d^?1, respectively. The obtained results suggest the capability of the proposed approach to correctly partition evaporation and transpiration components during both the irrigation season and rainy period also under conditions of significant reduction of actual ET from the potential one.     

机-电耦联条件下水力发电系统暂态分析

本文研究了水电站引水、水轮发电以及调节控制系统(水-机-电系统)的耦联建模及暂态分析方法。在水-机-电系统耦联框架下,首先基于耦合水击理论的4-方程模型,利用其结合部耦合机制,通过压力钢管与水轮机活动导叶的结合部耦合连接水轮机系统,导出了引水系统与水轮机系统的耦联模型。其次,将水轮机模型综合特性曲线转化成对应不同开度的插值特性曲线,结合一阶发电机模型和调速器控制方程,导出了水轮机系统与电力系统的耦联关系,从而建立了单机单管无调压井水力发电系统水-机-电耦联非线性模型及其求解方法,实现了具有不同物理属性的力学系统内部参数耦联的暂态分析。数值算例表明,提出的模型和计算方法能反映水力发电系统暂态过程与电力负荷扰动的动力学机制,可较好地响应来自电力系统的功率扰动,并有效预测暂态过程中各系统的参数变化规律。