应用遗传编程分析管网漏失监测信号

针对北京市供水管网漏失声学监测系统存在大量误报的问题,进行了现场信号衰减试验,并建立了信号在管道中传播的衰减模型;收集了报漏数据和实际漏失排查结果,采用遗传编程,开发了漏失监测信号判别模型,为辅助漏失排查提供了支持,提高了用户对管网漏失监测系统的使用效率。     

Simultaneous placement of renewable DGs and protective devices for improving the loss,reliability and economic indices of distribution system with nonlinear load model

ABSTRACT

In this paper, the simultaneous placement of renewable distributed generation (DG) and protective devices are discussed in the distribution system with nonlinear load model. The load model is considered as a combination of various customers’ daily load patterns and sensitive to voltage frequency. The considered DGs are wind turbine and photovoltaic. The breaker, relay and fuse are considered as protective devices. The objective functions of the problem consist of the active and reactive power loss, the reliability index and the profit of company of distribution system. The whale optimisation algorithm is used for multi-objective optimisation. Moreover, a method based on fuzzy set theory is employed to extract one of the Pareto-optimal solutions as the best compromise one. The proposed algorithm is implemented on the 69-bus distribution system and actual 101-bus distribution system in Khoy–Iran. The results indicate the high performance of the proposed method in improving the technical and economic indices of the network.     

A multi-objective approach for detecting and responding to accidental and intentional contamination events in water distribution systems

The protection against contamination events in water distribution systems involves two distinct phases: detection of the presence of a contaminant and implementation of actions to isolate and/or expel it rapidly. The problem of detection is confronted by installing a series of monitoring stations, strategically placed across the distribution system and consisting of sensors to detect the presence of contaminants. The actions to be implemented may include operations on distribution system devices (valves and hydrants) or injection of reagents to eliminate the contaminant, or simply alert users. The procedure proposed here attempts to address the problems related to the two phases by means of two consecutive optimisation processes, both of them performed off-line and assuming a specific 24-hour water demand sequence in each network node, whereas the accidental/intentional injection of contaminant can occur in any node and at any hour of the day. With reference to this vast range of possible injection scenarios, the first multi-objective optimisation process defines the position of a pre-selected number n_s of sensors across the distribution system in order to minimise the expected percentage of undetected contamination events and the expected volume of contaminated water consumed up to the beginning of the response operations following detection. A single configuration of stations is then selected from the Pareto front produced by this optimisation process (‘knee point’ of the Pareto front). At the end of this first optimisation process and with reference to the selected set of sensors, a potentially contaminated area in the network is associated to each sensor for each sub-period of the day. The second multi-objective optimisation process is then aimed to identify, with reference to each station and sub-period, and thus inside the corresponding potentially contaminated area, the hydrant-opening and valve-closing operations to be carried out in order to minimise both the number of operations and the expected volume of contaminated water consumed between the beginning of the response operations and the disappearance of the contaminant, assuming the availability of an unlimited number of response teams. Once these devices have been identified (‘knee point’ of the Pareto front relevant to the second optimisation process), an a posteriori analysis is performed to determine the sequence in which they should be activated based on the number of response teams actually available. In these optimisation processes, a hydraulic and quality simulator (EPANET) is linked to a multi-objective genetic algorithm (NSGA-II) in order to compute the value of the objective functions of the problem across different contamination scenarios. The results obtained applying the procedure to a real and complex water distribution system have shown it to be a robust and effective method for reducing the impact on the population.     

中小学校的电气设计探讨

随着政府对教育的投入比重逐年提高．近年来新建改建的学校也越来越多．虽然学校的电气设计并不复杂。但变配电系统、照明及配电装置、弱电、防雷及接地等均有其一定的特殊性。其设计的深度直接影响到学生的学习环境和学校的经济利益。     

Auto-generated site layout: an integrated approach to real-time sensing of temporary facilities in infrastructure projects*

The use of computational algorithms is popular in method studies, especially in the aspects of knowledge that relates to construction site layout modelling. However, extant approaches in these seldom support automated tracking of construction resources and available spaces. As a result, it is often time-consuming and subjective to autogenerate site layouts. This paper describes the development and implementation of a component-level system that is capable of generating site layouts automatically. The system involves the integration of building information models, genetic algorithm and a radio frequency identification system that has the capability to report object locations in real time. System and software architectures are presented to illustrate the enabling technologies, subsystems and software that are required to facilitate the developed system. A case study is also presented to demonstrate the functionality of the developed system. The practical implication of this research is such that the reported findings builds on gaps in previous scholarly work to develop a system that models site layouts and the associated costs automatically. Findings from the study also facilitate both early signalling of pending delays and their immediate recovery protocols.     

基于多目标规划的重载运输车调度优化模型

重载运输是当今世界各地运输的重要方式之一,是世界铁路发展的趋势。重载运输车的出现以来,在运输大宗货物方面拥有运载量大、获得效益高、所用成本低廉等优势,它的运输组织促进国民经济发展起着巨大的作用。因此高效率的运输车调度组织是提高运输能力,增加运输收入的重要方法。本文结合运输中轨道的实际问题,通过利用优化理论的多目标优化思想提出了一种重载运输车调度组织的优化模型。基于传统的贪心算法,本文进行了算法上的提高,在实际应用上有很大的提高。     

The network-based energy management system for convenience stores

Convenience stores generally consume energy higher than other retailing merchants. As the problem of energy shortage becomes more serious during summer, almost all convenience stores sign a contract with power plants, which provides for fines if demand limiting occurs in Taiwan and many other countries. Therefore, a reliable and effective method to reduce their utility consumption is required for modern business and industry. This research integrates the remote sensors, the control network, and the embedded system technologies to construct a distributed energy management control system for dedicated convenience stores. Energy consumption can thus be reasonably managed with demand limits by measuring and analyzing the power consumption sources in four major subsystems of convenience stores, namely, (1) air-conditioning, (2) lighting, (3) heating, and (4) refrigeration. By applying the proposed demand prediction and control method, the demand limiting condition can be properly predicted, and the possible peak load can thus be eliminated via the network control mechanism. Moreover, by integrating the LonWork fieldbus and the WinCE operating system (OS), the proposed system has been successfully applied to a convenience store. The experimental results indicate that the proposed distributed energy management system suitably predicts the peak loading condition and successfully prevents its occurrence by switching the air-conditioning system without affecting the indoor temperature regulation.     

浅谈广州市萝岗区凯云楼的电气节能设计

电力是民用建筑中的主要能源,如何降低用电能耗已成为建筑电气设计的重点之一,文中依据电气节能设计理论并结合广州市萝岗区凯云楼工程项目设计实例,对供配电系统、电气照明系统和自动控制系统的电气节能设计及相关技术进行分析。     

政府和社会资本合作(PPP)项目多目标优化模型研究

在公共基础设施项目采用政府和社会资本合作(PPP)模式过程中,各利益主体为了自身利益最大化进行相互博弈而产生的项目融资熵不断增加,使得系统从有序走向无序。为了解决这一问题,有必要研究在满足PPP项目整体系统熵最小的条件下,尽量使各利益相关方获得较大的收益,保证PPP项目融资系统的有序性。构建了基于熵视角的PPP项目融资多目标优化决策模型,借助Matlab工具,利用遗传优化算法对PPP项目多目标优化决策模型进行求解。通过实例验证,取得了较好的效果。     

Building energy system optimizations with utilization of waste heat from cogenerations by means of genetic algorithm

Distributed energy systems based on cogeneration offer significant potential to save energy since they effectively utilize waste heat from power generators. However, unless there is an appropriate combination of machinery and operations, the planned performance cannot be achieved. Thus, it is quite difficult to determine the optimal combination of machinery and operations. For this, an optimal design approach is needed. In this study, a new optimal design method for building energy systems is proposed. There are an enormous variety of combinations with regard to energy supply and demand. This method designs the most efficient energy system by optimizing the operation of available systems with consideration for the optimal capacity of machinery in the systems. Optimization algorithms known as “genetic algorithms” (GAs) with the capacity to deal with non-linear optimization problems have been adopted in this optimization analysis. In this study, a single-building energy system is evaluated. The result shows that the proposed method is sufficiently capable of optimizing the design, and has the potential to be applied to very complex energy systems with appropriate improvements.     

滑坡非线性演化行为的自组织进化识别

滑坡行为表现出复杂的非线性演化特征,位移是滑坡演化过程中所反馈出的重要信息之一。引入进化算法的全局优化思想,结合时间序列分析基本理论,以斜坡位移时间序列为基础,将遗传规划和遗传算法有机结合在一起,设计了一种模型结构和参数分别进化、共同识别的进化方案,实现对斜坡演化的非线性动力学模型结构和参数的全局最优识别。以新滩及八尺门滑坡为例对滑坡的发展孕育过程进行分析,结果表明,新方法识别获得的非线性动力学模型预测效果较理想,而且表现出较高的自组织进化识别能力。     

Optimisation of contraflow operations: Model and algorithm

There are two problems associated with contraflow operations, namely, the lane configuration problem and the scheduling problem. The former determines the optimal lane reversing scheme for the operation while the latter decides the start time and the duration of contraflow. In this study, both problems are modelled under one bi-level programming model. The upper level problem gives the optimal lane configuration and schedule by minimising the total travel time of the study area, while the lower level is a traffic simulation model that can capture the response of drivers towards the network changes. A hybrid metaheuristic-traffic simulation methodology is suggested to solve the proposed model. An illustrative case study of Singapore arterial network is adopted as an example to test the effectiveness of the proposed model and algorithm. Results show that by considering these problems simultaneously, an overall optimal solution can be obtained compared with solving the problems individually.     

混凝土泵车布料机构运动学分析及轨迹规划控制建模与仿真

本文给出了以混凝土泵车各臂油缸长度为参变量的布料机构浇筑过程的轨迹规划计算方法 ,在解决布料机构运动学分析的逆问题时 ,采用了基于多峰值并行搜索的遗传算法来求解最优控制优化目标函数 ,并对施工过程进行了仿真     

Multi-objective and probabilistic decision-making approaches to sustainable design and management of highway bridge decks

The aging and deterioration of highway bridges and the new requirements for sustainable infrastructures and communities require innovative approaches for their management that can achieve an adequate balance between social, economic and environmental sustainability. This paper presents a multi-objective decision-making approach for the sustainable design and management of highway bridge decks, which can consider several and conflicting objectives, such as the minimisation of owner's costs, users costs, and environmental impacts and uses goal setting and compromise programming to determine the satisficing and compromise solutions that yield the best trade-off between all competing objectives. The proposed approach is based on robust reliability-based mechanistic models of the deterioration and service life of reinforced concrete bridge decks, which include diffusion models for the prediction of chloride ingress into concrete and steel corrosion and thick-walled cylinder models for the prediction of stresses induced by the accumulating corrosion products in the concrete cover. The proposed approach is illustrated on the life cycle design and management of highway bridge decks using normal and high performance concrete. It is shown that the high performance concrete deck alternative is a Pareto optimum, while the normal concrete deck is found to be a dominated solution in terms of life cycle costs and environmental impacts.     

巴基斯坦人马座项目供配电系统优化设计

介绍巴基斯坦人马座工程11kV配电系统、自备柴油发电机供电系统,及两系统的优化设计。依据国内外规范和标准,结合项目负荷性质、用电容量等工程特点,优化原国外设计方的供电方案,在满足相关标准的基础上,为建造方大大节约了投资。     

基于节能低碳的管网优化研究

应用全生命周期法分析供水管网不同管材组合的各阶段能耗,为兼顾经济性和低碳降耗,建立供水管网的能耗函数与管网经济性函数耦合组成多目标优化函数.采用C++平台智能遗传算法对供水管网多目标优化函数进行求解.最后以某城市局部区域的管网为实例进行模型实际应用,计算结果能够在保证经济性的基础上兼顾管网全生命周期的能耗以及管网的供水安全,较好地与实际相吻合.     

实数型编码遗传算法校核管道摩阻系数

通过测试消防栓等手段，产生用于管网参数校核的不同工况，并对管网中管道摩阻系数进行合理分组，构建参数校核的最优化数学模型，利用实数型编码的遗传算法进行求解，结果表明可以较好地修正管道摩阻系数值，提高模型的使用精度。