浅谈给水管网布置方法

进行给水管网系统规划和布置,提出给水管网优化设计的高速公路理论和多工况控制进行给水管网优化设计的方法,编写计算机软件系统,应用这一全新的管网规划和优化设计理论进行管网的优化设计,可使所设计的管网系统能够满足近期和远期的供水要求、避免在施工中出现的大范围破坏路面的问题,并可节省工程投资,使供水条件更有利。     

城市给排水管网问题及优化设计

主要从城市给排水管网的设计进行分析,对工程中常用到的优化方法进行简单介绍,并结合城市管网的优化设计内容进行详细的论述.给水管网是城市的重要基础设施,管网设计时,在满足城市供水水量、水压和水质要求的基础上,研究管网年费用最小的优化设计方法具有重要意义.     

基于模糊层次分析的城市燃气管网安全评价

城市燃气管网是城市公共基础设施的重要组成部分,建立适宜管网安全的评价方法是保障管网安全的重要手段。本文基于规范标准和工程实例,构建城市燃气管网安全风险源指标体系,将改进层次分析法算法和模糊综合评价方法引入管网结构安全评价中,对城市燃气管网风险等级进行评价。采用改进层次分析法确定评价体系中各指标的权重,利用模糊综合评价方法建立模糊评价模型,以柯西函数为隶属度函数计算隶属度值,根据最大隶属度原则确定管网风险等级。将评价方法应用于浙江省杭州市某管网系统,计算结果与专业检测报告一致,表明本文评价方法的可行性和实用性。     

地理信息技术在供水管网上的研究与应用

以华北某城市的供水管网信息系统建设为例，介绍了供水管网地理信息系统的开发目标、功能、系统的结构。系统的建立为该公司的供水生产管理水平提高到新的台阶，为企业信息化的建设打下了坚实的基础。     

供水管网的技术管理探讨

在城市供水管理工作中,为保证安全供水,维持管网的正常工作,必须做好日常的管网养护管理工作,建立一套完整的供水管网维护管理标准及技术规程,为行业管网维护管理技术规程建立提供参考.     

城市多源式供水管网调度节能的主要途径

广州市自来水公司属多水源的供水系统,属下有6间水厂和28个加压站,供水管网约有5100多公里。供水调度优化的问题也同样有待调度决策系统进一步发展和完善,并依托用户信息管理系统的开发和供水管网动态模型的建立而逐步优化。文章从优化管网平均压力和各水厂的供水量,建设加压站等方面论述了城市多源式供水管网调度节能的主要途径。     

城市供水管网建设与管理技术研究

随着社会的飞速发展和城市建设的不断进步，地下管道的大量增加，城市地下空间资源显得越来越重要。在城市的建设当中，如何建立起好的供水网管网，已成为一个很重要的社会问题了。城市供水管网建设与管理是一项相对复杂的工程，需要通过设计计算、报批、建立数据库、GIS系统维护等方面来实现整体的布局和管理。本文主要针对城市的供水网络的建设设计和日后的管理进行详细的分析。     

城市供水管网漏损成因及控制初探

管网漏损是供水企业所面临的共同问题，其不仅会造成直接经济损失、影响供水安全，还会造成其他后果。随着城市供水规模越来越大，问题也越来越明显。文章主要探讨管网漏损的原因，并从城市供水管道的设计、施工、运行管理等各方面提出降低漏损率的措施。     

城市供水管网维护抢修工作探讨

城市供水管网维护抢修工作是供水管网安全供水的一项重要工作。因此,如何开展快速、高效的供水管网抢修工作就显得十分重要。缩短抢修时间,提高供水管网的抢修速度,是供水公司每个员工共同关心且急需解决的现实问题。笔者就蚌埠市供水管网维护抢修中的心得和体会与同行共同探讨。     

基于InfoWorks城市供水模型的建立及应用

城市供水管网是城市重要的基础设施之一,供水管网的安全高效运行是城市持续、稳定发展的重要保障[1]。本文介绍了利用Info Works WS软件对昆明市草海试验区的供水管网建立水力模型的过程,包括该地区管网的基本情况介绍、基础数据的导入与处理、模型的建立过程、模型的运行及校核等方面的内容,并针对模型在供水业务日常运营中的具体应用等方面进行探讨。     

基于模糊系数的证券投资组合选择模型

利用模糊数来描述证券的期望收益率和风险损失率,从而对证券组合投资问题建立相应的模糊线性规划模型,并以模糊数排序为基础将该模型转化为普通线性规划模型,最后讨论模型的求解方法,并出了一个具体的算例。     

带有模糊参数的城市生活垃圾逆向物流网络设计

在垃圾回收逆向物流网络中,回收的数量具有不确定性,根据这一特点,将各消费区域垃圾回收量看成模糊参数,提出了逆向物流网络的模糊约束机会规划模型,通过把模型中模糊机会约束清晰化,将模型转化为确定性的0—1整数规划模型,通过算例,针对不同的置信水平对模型进行了求解,为逆向物流网络设计提供了依据。     

Designing an integrated humanitarian logistics network for the preparedness and response phases under uncertainty

In the current paper, a model of possibilistic location-allocation is proposed for designing a multi-period bi-objective humanitarian logistics network that pursues a reduction in the total cost and maximizes the total network coverage. The model considers the inventory management of perishable relief items and the flow of affected and wounded people in pre-disaster and post-disaster phases, simultaneously. Moreover, wounded people are categorized according to the injury severity. The uncertainty associated with key parameters is also addressed. To handle the uncertainty, a fuzzy chance-constrained programming method originated in the Me measure is used. The purpose of this measure is to prevent the extreme attitudes of the decision maker by considering the combination of possibility and necessity measures and using the optimistic-pessimistic parameter. This paper presents a solution procedure derived from a fuzzy interactive programming approach and two meta-heuristic algorithms, imperialist competitive algorithm and invasive weed optimization, so as to solve the study model. As for the validation of the proposed model and solution procedures, a number of test problems have been generated. A real-life case study is also implemented to instantiate whether the proposed model is applicable or not.     

Mathematical methods of optimization for multi-objective transportation systems

Transportation systems have multi-objective functions and there are multi-factor decision situations. A general mathematical optimization model for such systems is developed which has broad applications for the planning, system design and evaluation of many transportation systems. Three types of solution techniques are discussed. For multi-objective linear programs, a solution is obtained which satisfies the decision maker's preferences and optimization from the decision maker's point of view is considered. A goal programming solution technique is given when goals for the system can be defined. If this is not possible, an overall utility function is defined on the various objective functions and a concept of additive utilities is explored and a parametric programming solution is given.     

Some Applications of Input–Output Analysis in a Gold Mine

In this paper, some applications of a mixed physical-financial input–output model for a large gold mine in China are described. This mixed input–output model is a basic part of the mine's decision-making system, called an interactive and hierarchical multi-objective feedback decision-making system of the gold mine's production and management. The model is used for the following: (1) to analyze quantitatively how the changes in the economic, technical and geological factors affect the mine's production and management; (2) to search for a series of bottleneck components in the mine when the capacities of some components of the mine change; (3) to optimize mine planning with the help of mathematical programming (linear programming, 0–1 programming) and computer simulation.     

一种算法改进的模糊神经网络及其性能分析

将T-S模糊模型与前馈神经网络相融合构造了一种新型的模糊神经网络,该模型采用基于梯度下降法和算法相结合的混合学习方法,其中梯度下降法用来训练高斯型隶属度函数的非线性参数,而算法用来训练线性参数,即权值。从理论上,证明了该模型对非线性函数的万能逼近能力。仿真实验表明,该模糊神经网络用于非线性动态系统辨识的有效性。     

A priority-based multi-objective framework for water resources diversion and allocation in the middle route of the South-to-North Water Diversion Project

Because of the degradation of the social-ecological-economic-environmental (SEEE) system, water scarcity has been a growing source of conflicts over the globe. Further, the uncertainty arising from complex water resource scenarios increases the conflicts between the different water users and destabilizes water allocation systems. In this study, a priority-based multi-objective programming (MOP) model (quantitative path) with fuzzy random variables (FRVs) is established for a water resource diversion and allocation (WRDA) problem. To determine the priorities of the multiple objectives, a priority-determination approach (qualitative path) is designed, comprising of a pressure-state-response (PSR) multiple attribute assessment system and a technique for order preference by similarity to an ideal solution (TOPSIS)-based evaluation method. Then the MOP model is transformed into a solvable goal programming (GP)-based model. Because of the inclusion of FRVs, the obtained results can be adjusted to local conditions in view of social, economic, environmental and ecological objective priorities. Therefore, they are more applicable than traditional weight sum or Pareto multi-objective WRDA methodologies. A case study from the middle route of the South-to-North Water Diversion Project (SNWDP-MRP) in China is given to demonstrate the practicability and rationality of the proposed methodology in obtaining scientific WRDA plans.     

Ranking sectors using fuzzy output multipliers

Using input–output analysis to model the effects of changes in industry final demands is fraught with problems, many of which relate to the fundamental limitations of the concomitant linear framework. A further issue concerns the accuracy of the results, a consequence of the uncertainty surrounding the values of multipliers. Such uncertainty can create problems where the values of output multipliers are used to inform resource directions. This paper utilizes (and develops) a fuzzy input–output model and investigates the ranking of industries based on fuzzy output multipliers. The non-triviality of the fuzzy model is exposited in a general problem, where imprecision is defined by a proportional level of imprecision (fuzziness) in the technical coefficients. Through a nascent method for ranking fuzzy numbers, comparisons are made between the fuzzy and more traditional (non-fuzzy) analysis.     

A goal programming model for achieving racial balance in public schools

This paper develops a goal programming model for achieving racial balance in segregated public schools. The model is illustrated and offered as an improvement upon linear programming, a model previously applied in the literature which allows a single objective function only and, in comparison with goal programming, requires more variables and constraints. Goal programming, a member of the general multiple objective linear programming (MOLP) model, improves upon these among other disadvantages thereby emerging as a more efficient tool for student assignment problems.     

企业内部价值链优化模型研究——以西安市某装备制造企业为例

文章基于有效的管理企业价值活动这一目的,提出了一种层次分析法和模糊线性规划相结合的优化企业内部价值链的模型。模型中基于层次分析法推导出评价指标体系中各指标的综合权重;采用模糊线性规划法,建立适合价值链评价的综合数学模型,并通过测算得到最终的内部价值链优化模型。研究表明,层次分析法大大简化了各指标的权重计算,模糊线性规划使内部价值链管理的效果得到了定量研究,从而科学地建立了优化模型。