蚁群算法在工程项目工期—费用优化问题中的应用

论述了工期—费用优化问题的原理,分析了传统优化方法的优缺点。针对工期-费用这一连续空间优化问题,综合了基于网格划分策略的连续域蚁群算法和求解旅行商问题的基本蚁群算法的思想,构造了一种改进的蚁群算法。实例计算结果表明,该方法在求解工期费用优化问题方面是有效的。     

计算机监控系统可靠性冗余方式的设计与实施

为了提高计算机监控系统的可靠性，根据监控系统结构和形式的不同，将其系统安全性、可靠性的冗余方式归纳为电源冗余、控制器冗余、输入／输出冗余和通信冗余，以及应用软件的安全与冗余等方式。文中对龙羊峡水电厂计算机监控系统可靠性的冗余方式作了详细介绍。     

计算机监控系统可靠性冗余方式的设计与实施

为了提高计算机监控系统的可靠性，根据监控系统的结构和形式不同，其系统安全性、可靠性的冗余方式大致可归纳为电源冗余、控制器冗余、输入／输出（I／O）冗余和通信冗余以及应用软件的安全与冗余等方式。本文就龙羊峡水电厂计算机监控系统可靠性的冗余方面作了详细的介绍。     

基于MOPSO的RC单柱墩全寿命抗震性能多目标优化设计

采用MATLAB模块化编程将多目标粒子群优化算法MOPSO和反应谱分析联合起来进行抗震优化设计。根据桥墩在E1和E2两级设防水准地震作用下的抗震性能,采用Pushover分析墩顶的最大漂移率以及概率统计的方法得到全寿命期费用模型对应的工程费用,从而得到费用最小的Pareto解。数值计算结果表明:MOPSO算法和反应谱分析结合能够很好的应用于桥梁全寿命抗震性能设计分析,算法的收敛性和稳定性好,所求得的Pareto最优解在解空间分布均匀且范围较广,可以为桥梁设计提供良好的方案选择空间。更多还原     

排水管道工程费用函数建立

排水管道工程费用大多依据管道建设费用而定,为了更准确预估排水管道的工程费用,将其分为管道费用、检查井费用两部分,并分离出两费用中的土方费用。对于确定土方量,土方费用仅与当时人工费用相关。通过对土方量进行回归分析,在假定人工费用有确定增长率的前提下,以2008年挖掘单位体积土方的人工费用为基准,获得了预测未来年份的土方费用的通用公式。利用2008年《天津市市政工程预算基价》拟合出管材费用、管道土方费用、检查井材料费用、砌井人工费用以及检查井土方费用的表达式,得到了排水管道工程的费用函数。     

微机监控系统可靠性的设计及展望

为了提高计算机监控系统的可靠性,可根据监控系统不同的结构和形式,将电源冗余、控制器冗余、输入/输出(I/O)冗余和通信冗余以及应用软件的安全与冗余等方式改善并优化     

冗余技术在水电站计算机监控系统中的应用

分析了冗余技术在水电站计算机监控系统中的配置模式和可靠性设计。阐述了单星形、双星形和双环网等3种结构冗余以及电源冗余、存储冗余和信号冗余等3种功能冗余,介绍了冗余模式与主备模式的异同以及具体实施。     

多因素耦合的内河限制性航道维护底宽确定方法

航道维护底宽是内河航道养护管理工作的重要指标之一。为探究限制性航道维护底宽的确定方法,基于航海学和可靠性理论,分析计算了满足通航标准、船舶运动特性、航行可靠性的航道底宽,构建了内河限制性航道维护底宽的效益-费用模型。其中效益模型由船舶运输、节能减排、替代公路运输以及防洪等效益构成,费用模型由一次性疏浚及日常维护等费用构成。在此基础上,耦合多因素综合分析计算了京杭运河镇江段的航道维护底宽,结果表明该航段40 m维护底宽较为合理。该限制性航道维护底宽确定方法较好地考虑了内河限制性航道多因素多目标需求,具有较高实用价值。     

注入方波电压式转子接地保护改进方案

提出了一种改进的注入方波电压式转子接地保护方案。该方案通过数据采集回路和算法的冗余化提高了保护的可靠性,无需引入励磁电压,保证了运行维护的安全性。根据该方案研制的保护样机其硬件成本得到了有效控制,有利于产品的推广使用。     

基于免疫算法的配电网开关优化配置模型

给出了开关优化的数学模型及基于免疫算法的求解方法。分析了开关投资和运行维修费用、停电损失的计算方法，基于等年值法建立开关优化配置模型。该模型是一含约束、不可微、非连续的组合优化模型。基于免疫算法给出了模型的求解算法。通过模型计算确定开关的最优配置数量和位置，并得到系统的可靠性、投资费用和停电损失等。计算实例表明：提出的模型和算法有较强的工程实用性，免疫算法具有较好的全局收敛性和较快的收敛速度。     

基于全寿命周期成本理论的水工结构维修加固决策模型

鉴于补强修复和除险加固作为水工结构领域中一项重要工作和长期任务,对保障工程服役安全、发挥工程效益、延长工程服役周期等具有极其重要的意义,在保证结构安全可靠的前提下,考虑结构性能的劣化特性,从优化工程全寿命周期成本的目标出发,引入全寿命周期成本理论,研究水工结构维修加固成本计算与决策模型及其算法,并应用于某水工结构工程中,优化制定其全寿命周期内具体维修方案。研究结果表明,文中所述模型可为制定水工结构工程在全寿命周期内的维修加固策略提供一定的科学依据。     

Optimization of Sewer Networks Using an Adaptive Genetic Algorithm

This work aims at introducing an optimization model to design sewer networks. The approach specially focuses on handling the nonlinear and discrete constraints of the problem. For this purpose, an adaptive genetic algorithm is developed so that every chromosome, consisting of sewer diameters and slopes and pump indicators, is a feasible design. The binary chromosomes are freely generated and then decoded to feasible design alternatives following a sequential design-analysis algorithm. The adaptive decoding strategy is set up based on the open channel hydraulics and sewer design criteria. Through the proposed method, all the sewer system??s constraints are systematically satisfied. Consequently, there is neither need to discard or repair infeasible chromosomes nor to apply penalty factors to the cost function. A benchmark sewer network from the literature is considered to be designed using the proposed approach. The obtained results are then discussed and compared with the previous works. It is found that the adaptive constraint handling method computationally makes the optimization more efficient in terms of speed and reliability.     

基于西门子S7-400系列PLC的现地控制单元冗余设计

讨论了基于西门子S7-400系列可编程逻辑控制器（PLC）的水电厂计算机监控系统现地控制单元的冗余设计，对硬件冗余结构和特点、软件冗余原理及其实现进行了详细描述，并强调了电源及重要输入输出的冗余设计。这种冗余设计可大大提高计算机监控系统的可靠性，满足水电厂实现“无人值班”（少人值守）的要求。     

MULTI-OBJECTION OPTIMIZATION MODEL BASED ON RELIABILITY FOR WATER DISTRIBUTION SYSTEMS

1.INTRoDUCTIoNTheoptimizationofwaterdistributionsystemsbasedonreliabilityhasdrawnmoreandmoreattention-Themajorissueofwaterdistributionsystemreliabilityisconcernedwiththeabilityofthesystemtosupplydemandatthenodesordemandpointswithinthesystematrequiredminimump.essures.Theconventionaldesignprocessesforwaterdistributionsys-temsaretrialandQrrorpLoCeduresthatattempttofindadesignthatrepresentsaleast-costsolution,whicheanmeet'ng'demand.Thesetrialanderrormethodsmakenoattempttoanalyzeordefineanyrel…     

Conjunctive Management of Large-Scale Pressurized Water Distribution and Groundwater Systems in Semi-Arid Area with Parallel Genetic Algorithm

This study develops a production well management model for the conjunctive management of water resources in semi-arid areas. The management model integrates a large-scale pressurized water distribution system and a three-dimensional groundwater model under an optimization framework. The well pump operations optimization problem is formulated as a Boolean integer nonlinear programming (BINLP) problem to optimize the periodic 24-h pump on/off operations over a 1-week operation horizon. The management model considers multiple objectives and is solved by a parallel genetic algorithm (PGA) to overcome the difficulty of solving the BINLP problem. The PGA significantly reduces computation time for a case study in Chandler, Arizona. The Chandler water distribution model is built based on EPANET, and the Chandler three-dimension groundwater model is developed using MODFLOW. The high performance computing (HPC) of the genetic algorithm makes it possible to obtain 24-h real-time operations in the 7-day forecast model. The tank reliability, resilience, and vulnerability (R-R-V) are evaluated to infer the system reliability. The Pareto curve provides compromise solutions between the two competing objectives of energy reduction and pressure violation reduction.     

工程造价统一计算的模型分析

通过对工程造价计算的共性进行研究分析，在对生命周期成本进行分解和构造成本函数的基础上建立了适用于不同行业、建设项目生命周期不同阶段的工程造价统一计算的数学模型，并给出了用计算机实现工程造价统一计算的步骤和流程分析．     

考虑全寿命周期成本的供水管网优化设计

针对城市管网的传统优化设计中仅考虑初始投资而没有考虑运行过程中维修管理成本的问题,提出了基于全寿命周期成本(LCC)的管网优化模型和计算方法。通过对管网建造成本及运行阶段维修管理成本的定量分析,建立了以全寿命周期总费用最低为目标的优化模型,并利用PSO算法对管径进行优化设计。通过实例分析,分别得到两种常用管材的最优管径,并基于寿命周期成本对比分析为管网设计阶段的方案选择和优化设计提供了依据。     

PID算法在船闸控制系统中的应用

将PID算法应用到船闸控制系统中,设计PID控制系统,并根据实际控制要求对传统PID算法改进,使闸门的开启和关闭过程更加柔性和协调。现场实验数据表明,使用PID算法后,船闸系统的运行速度大大提高,而且系统的运行更安全可靠。     

Reliability-Based Pipe Size Computation of On-Demand Irrigation Systems

The variability of flow regimes in on demand pressurized irrigation systems leads to uncertainty in head at the nodes affecting the system performance, and thus it should be considered when designing and/or rehabilitating water distribution systems. Based on these considerations a new approach for the optimization of on demand pressurized irrigation systems is presented combining the minimization of cost with the maximization of reliability taking into account the stochastic variability of the flows into each section of the network. The new model, Clément and the cumulated random generated discharges model (FAO model) were applied to three pressurized irrigation networks of different dimensions (large, medium and small) operating on demand in Southern Italy. The optimization algorithm used in all the cases is the Labye iterative discontinuous method, a formulation of the dynamic programming. The results of the different models were compared showing that the cost of the optimal network calculated using the new model was reduced by more than 20%, without any significant decrease of the system reliability or reduction of the network capacity.