Network Management - The Bradford Experience

The paper reviews the concept of network management in the Western Division of Yorkshire Water and looks closely at its implementation in the Bradford area, together with the role played by an integrated team of staff from Yorkshire Water and Parkman Consulting Engineers.
The individual initiatives which have been integrated into the network-management programme are identified, and progress on the major ones - network analysis, leakage control, pressure reduction, and telemetry - is discussed together with the details of planned future extensions and developments.     

燃气管道泄漏风险控制系统

探讨了燃气管道泄漏风险控制系统的建立和技术方法。对燃气管网进行风险评估,确定重点监控管道,结合压力管理与在线检测技术对燃气泄漏风险进行有效控制。     

Management of chlorine dosing rates in urban water distribution networks using online continuous monitoring and modeling

The aim of this study is to present the results of a research which was undertaken to manage chlorine dosing rates in a real water distribution network using online continuous monitoring and modeling. The study area was divided into 18 district metered areas (DMAs) where the water pressure and flow rate measurements to each DMA were online and continuous. Besides, online water quality sensors were installed at eight different locations and a bimonthly water quality measurement and sampling program was carried out. The data sets required to set, calibrate and verify the hydraulic and chlorine models were derived from the online continuous monitoring and sampling program. Eight chlorine management scenarios that take into consideration the extreme conditions found out during the online monitoring and sampling were utilized. The study revealed that online monitoring provides excellent data sets for chlorine modeling and management that enables automatic application of chlorine dosing.     

市政给水管网漏耗控制分析及对策研究

通过对市政给水管网漏耗控制方面的分析,探讨了管网漏耗的原因,并结合工作实际,提出了管网在管理和运营方面的解决方法,有效控制了管网漏耗量,达到了降低成本,提高供水企业生产效益的目的。     

Smart meter enabled disaggregation of urban peak water demand: precursor to effective urban water planning

The implementation of a smart water metering system in Hervey Bay in 2006–2007 allowed the local water utility to record the hourly water consumption of all its customers. This data availability has enabled a large scale research project to proceed with the aim to disaggregate peak hour, peak day and peak month demand in the water distribution network into primary indoor usage (e.g. shower, washing machine, etc.) and irrigation components. Such information can guide the development of alternative tariff structures and other demand management initiatives aimed at reducing peak demand. This paper details results of the analyis of average hour, peak hour, peak day and peak month consumption data of 2884 residential customers selected from four District Metered Areas (DMAs) located in the city of Hervey Bay in Queensland, Australia.     

基于WSR方法论的高速公路全面造价管理研究

文章采用东方的系统工程思想,分析其在中国高速公路项目中实施情况。研究了物理—事理—人理（WSR）方法论及基于WSR方法论的高速公路全面造价管理方法,阐明利用WSR方法论指导全面造价管理实施是一种有效方法。通过工程实例运作进行分析,阐明了用于WSR方法论的高速公路全面造价控制的实施步骤。     

Modelling ultrafine/nano particle dispersion in two differential mobility analyzers (M-DMA and L-DMA)

In the present work, the dispersion of ultrafine/nano particles in two differential mobility analyzers (DMA) namely, a medium DMA (M-DMA) and a long DMA (L-DMA) is numerically analyzed using the Lagrangian tracking method. Simplified geometries of the two DMA’s (M-DMA and L-DMA) that are truly representative of a wide class of DMAs have been considered for the present analysis. The exact profiles of velocity and electric field are used for conducting the present investigation. The Langevin equation is numerically solved to track the particles inside the DMAs. The Brownian force has been modelled as a Gaussian white noise random process. The effect of Brownian force on the dispersion of ultrafine/nano particles is clearly evident from the present investigation. The performance evaluation of both the DMAs have been carried out by comparing the transfer functions obtained using the present methodology with the widely accepted transfer functions of Knutson & Whitby and Stolzenburg. The numerical results obtained using the present methodology compare quite well with the experimental data available. It is also shown that DMAs with smaller effective electrode lengths have higher collection efficiencies for real nano-sized particles.     

Performance Assessment of Pressurized Stairs in High Rise Buildings

Pressurized stair cases are an important part of the fire safety strategy of high rise buildings. Long egress times are compensated by creating safe environments within egress staircases allowing the displacement time within those stairs as time where occupants can be considered safe. The main mechanisms by which stairs are “made safe” are by guaranteeing structural protection of the enclosure and by elevating the pressure within the stair to ensure that smoke cannot enter. Despite the critical importance of this element of the fire safety strategy, the analysis and implementation of these systems remain simplified. Simple models have been developed using Bernoulli type formulations that account for static pressure and empirical constants to calculate flows through doors and other leakage areas. Implementation of these systems is even more simplified, consisting mainly of a direct feedback loop that controls a fan output on the basis of a pressure measurement inside the stair. The flow induced by the fan guarantees a minimum pressure. The pressure inside the stair needs to be limited to enable doors to be open, thus pressure dampers are introduced to release airflow in the event the pressure exceeds a specified maximum. Validation of these methodologies was done in the 70s and 80s with very limited field validation in real systems. This study presents an assessment of the performance of pressurized staircases in six high rise buildings. All systems have been designed using a similar methodology but implemented in different ways. In all cases the control mechanism for the fan is a direct feedback loop from a single pressure sensor. The results have been evaluated showing the limitations of the control system in the event of multiple doors being opened and the limitations of the pressure release dampers (as a response mechanism) if the pressure becomes unstable.     

Leakage detection and location in water distribution systems using a fuzzy-based methodology

Loss of water due to leakage is a common phenomenon observed practically in all water distribution systems (WDS). However, the leakage volume can be reduced significantly if the occurrence of leakage is detected within minimal time after its occurrence. This paper proposes a novel methodology to detect and diagnose leakage in WDS. In the proposed methodology, a fuzzy-based algorithm has been employed that incorporates various uncertainties into different WDS parameters such as roughness, nodal demands, and water reservoir levels. Monitored pressure in different nodes and flow in different pipes have been used to estimate the degree of membership of leakage and its severity in terms of index of leakage propensity (ILP). Based on the degrees of leakage memberships and the ILPs, the location of the nearest leaky node or leaky pipe has been identified. To demonstrate the effectiveness of the proposed methodology, a small distribution network was investigated which showed very encouraging results. The proposed methodology has a significant potential to help water utility managers to detect and locate leakage in WDS within a minimal time after its occurrence and can help to prioritise leakage management strategies.     

供水管网的泄漏及压力管理

通过压力管理减少供水管网泄漏损耗是近几年在国外出现的新理念，它有效地解决了供水管网漏损这一棘手问题。对管网压力的控制可以有效地避免管网中不必要高压力的出现。减少爆管事故的发生进而降低漏损率。笔者介绍了压力管理的概念及实现方法。     

管网压力控制模型与DMA分区减漏探讨

介绍了管网压力控制模型的功能及建立过程,并将其应用于桂城水厂。运行结果表明,采用管网压力控制模型后,桂城水厂平均出厂压力为0.483 4 MPa,千吨水电耗及漏损率分别降低6.28%和3.14%;用管网压力控制模型修正的压力代替宏观模型优化后的压力,有利于在供水调度过程中实现节能节水;管网压力控制模型与DMA分区阀门减漏联合作用,可以有效降低管网的漏损率;基于管网压力控制模型建立压力流量预测控制系统,使泵群按照管网压力曲线运行,可以降低电耗并减少漏损。     

燃气供销差的主要因素与整治

产生燃气供销差的主要因素在于管网漏损、计量偏差、抄收漏失、窃气损失。燃气供销差的问题主要是人的问题、管理的问题。整治燃气供销差必须以人为本,加强领导,整治管网漏损,加强计量管理,打击违章窃气,提高抄收到位率和准确率。     

Recent Developments in Application of 'Bursts and Background Estimates'Concepts for Leakage Management

ABSTRACT During the UK 'national leakage control initiative', which was carried out in 1991–94, Welsh Water formulated a conceptual model of leakage management which was intended for international application.
This paper explains how the concepts of 'bursts and background estimates'(BABE) have been calibrated and extended to cover financial/economic analysis and pressure management, using specialist software for practical application and following the methodologies in the recent water industry 'Managing Leakage'reports. Examples of applications of BABE software and concepts, in the UK and internationally, are also described.     

Accounting for Losses: The Bursts and Background Concept

Losses of treated water occur through leakage and overflows from the pressurized pipes and fittings in water undertakers'distribution systems and customers'private supply pipes. The UK National Leakage Control Initiative was formed in 1991 to update previous published work on leakage control policy and practice in the UK.
Although some published technical relationships exist, there has been no overall methodology which attempts to provide a component-based estimate of annual losses in different parts of the distribution system for any particular combination of local circumstances, i.e. pressure, burst frequency, burst flow rate, number of properties, length of mains, method of leakage control, standards of service, and waste notice service/enforcement policy.
The 'bursts and background estimate'spreadsheet-based methodology is designed to provide such estimates. It links 'night-flow'and 'annual losses'concepts, and can be used for a variety of purposes. These include (a) assessment of the likely incidence of losses for different leakage control and waste notice policies, (b) identification (from night flows) of districts in which there are unreported bursts, and (c) assessment of economic target levels for leakage control. The substantial element of annual losses from service pipes, and the considerable influence of pressure on annual losses, are also discussed.     

谱聚类在给水管网分区优化中的应用

利用图划分技术和图论算法实现给水管网分区。根据给水管网分析,确定分区数量,建立权重邻接矩阵并计算图拉普拉斯矩阵及其特征向量,通过多路图划分对隐藏在特征向量中的聚类信息进行数据挖掘,采用遗传算法和K均值方法实现最佳节点聚类。利用PageRank和最短路径算法确定水表和阀门位置,最终实现给水管网优化分区。实际给水管网模型分区实例表明所提方法在给水管网分区的有效性。     

Evolution of research on water leakage control strategies: where are we now?

ABSTRACT

This study provides an overview of the 21st century research trends for water leakage control strategies that focus on pressure management, active leakage control, pipe rehabilitation, asset management and District Metered Area (DMA) design. The biggest contribution comes from the research team in Italy, whilst the most active researcher is based in Greece. Research in this field has gained momentum from 2008 although a couple of studies have been conducted since 2000. Control strategies are receiving attention not only from academia but also from industrial players who are looking for technological advances by collaborating with academic institutions in research and development. The main strategy to reduce water leakage is the pressure management of water distribution systems using optimal settings of a pressure reducing valve installation. Despite available technologies, the commitment from the government, the water operators and the local consumers are the most important criterion for the effective implementation of water-leakage control strategies.     

管网供水压力与漏失量关系研究

采用夜间最小流量法对哈尔滨某小区进行实地试验,试验验证了供水压力与管网漏失量之间的关系,得出了管网漏失量与供水压力间存在着指数关系,可为供水企业通过合理分配管网压力来控制管网漏失水量提供参考。     

管网宏观模型的完善及节能减漏应用

基于宏观模型可建立管网压力控制模型,并将其应用于桂城水厂。运行结果表明,采用管网压力控制模型后,水厂供水范围合理,远端压力精度为±0．001MPa;控制泵群工况点沿管网压力曲线运行,调节后的流量和压力均能满足用户要求,同时使小区阀门减漏效应扩展至整个管网,可有效降低管网的漏损率;修正宏观模型及水力模型调度压力有利于在供水调度过程中实现节能节水。     

燃气输配管网完整性管理的探讨

论述了燃气管网完整性管理的概念和基本阶段,分析了在线检测、压力试验、直接评价等实施方法,提出了建立和完善燃气管网安全评价与管理体系的建议。     

Project risk management methodology for small firms

We present a project management methodology designed for small businesses (SMEs), who need to run projects beyond their normal operations. These projects are critical to the survival of these organisations, such as the development of new products to adapt to the market or new legislation, management system implementations, etc. Very frequently, the managers of these projects are not project management professionals, so they need guidance to have autonomy, using minimal time and documentation resources. The risk management method outlined in this paper is based on extensive research with a large number (72) of Spanish companies. This new methodology considers the factors that are usually neglected by SMEs; i.e., project alignment with the company's strategy and results management. The methodology, based on project risk management, includes simple tools, templates and risk checklists with recommended actions and indicators. For validation it was tested in five different types of real projects (innovation, management systems and ICT implementation) of industrial and service companies with different characteristics.