Report on application of sectorization method for creation of District Meter Areas (DMAs) within the water distribution network of the city of Amsterdam

The subject of this report is presentation of abilities of sectorization algorithm to identify and create District Meter Areas (DMAs) within the water distribution network of the city of Amsterdam. District Meter Area (DMA) is a distinct hydraulic area of the WDN, separated from the rest of the supply system by isolation valves and one or more metered inlets and outlets (Burrows et al., 2000). Sectorization of Water Distribution Network (WDN) into District Meter Areas (DMAs) is a proven measure for proactive leakage and pressure control. It is considered as the most cost-effective strategy for the control of real water losses. Setting up DMAs can be potentially useful even for water utilities that operate WDNs that do not suffer from high volumes of non-revenue water, such as Amsterdam city WDN operated by Waternet. For example, improved control of the contamination spreading can be considered as an additional significant benefit. Sectorization of WDN must be designed carefully, as required network interventions can endanger network’s reliability in terms of water supply and pressure distribution. Complexity of the real life WDN results in many different alternatives in which network sectorization can be done. Sectorization of WDN into an optimal system of DMAs is a hard task to achieve, especially for the existing and continuously operating WDNs. Every WDN is unique in its topology, characteristics and key sectorization objectives, so there is no common procedure for sectorization of WDN into DMAs, but rather a series of guidelines provided by the different water and other authorities (Butler, 2000; Farley, 2001; Morrison et al., 2007; WAA & WRC, 1985). Sectorization solutions are usually obtained by the “trial and error” technique conducted by a local expert, familiar with all the WDN specifics. Practical application of such approach is illustrated in Grayman et al. (2009) where two large case study networks are redesigned to implement typical DMA design and to allow additional control and isolation of the system in order to improve water security. Beside general criteria given by the aforementioned guidelines (e.g. DMA size, network length), sectorization process should be driven by the case-specific criteria such as required number of feeds, fire flow regulations etc. A more formal approach to sectorization problem, that will enable investigation of alternative sectorization solutions for large WDNs, adopting local design criteria is presented within this research program. Sectorization method employed in this analysis is named DeNSE (Distribution Network Sectorization). It is developed at the University of Belgrade, Faculty of Civil Engineering (Vasilic, 2018). DeNSE sectorization method is based on newly developed uniformity index metrics (Vasilic et al., 2020) which drives the sectorization process and identifies clusters in the network. Originally, DeNSE method relies on common engineering heuristics for placement of flow meters and valves to create DMAs. Although being able to produce a good set of feasible sectorization solutions, using only engineering heuristics limits the search space of potential solutions. In this research DeNSE methodology has been further improved to include an optimization procedure to ensure finding (sub)optimal sectorization solution within the broader specter of feasible sectorization solutions. Least investment for field implementation and maintaining the same level of WDN’s operational efficiency are adopted as sectorization’s main design criteria. Additional local design criteria, specific for the Amsterdam water distribution network, have been included also. These upgrades made to the original DeNSE method proved to be significant, which is confirmed by testing it on two real-life case studies which are part of Amsterdam WDN. Reported results prove that developed method can be used as a decision support methodology valuable to practicing engineers commencing implementation of sectorization strategy in WDN

Le problème de la sectorisation multicritère en cartographie

Les travaux présentés dans cette thèse visent à proposer des méthodes pour résoudre les problèmes de la sectorisation multicritère en cartographie. En premier temps, nous avons défini les problèmes différents de la sectorisation et nous avons établi les liens entre ces problèmes avec les problèmes classiques qui sont bien étudiés dans la littérature : le problème de découpage de district politique, les problèmes de localisation et le problème du partitionnement de graphe. Deux types de méthodes ont été abordés pour résoudre les problèmes de sectorisation. Des heuristiques ont été développées et elles consistent à calculer un optimum de Pareto pour les différents problèmes. Et pour le problème de sectorisation à partir de pôles, nous avons aussi utilisé et expérimenté un algorithme de boîte pour trouver une représentation du front de pareto. La méthode exacte branch and bound a été utilisée pour résoudre le problème de sectorisation sans pôle prédéfini optimalement. Avant que nous appliquons cette procédure, nous ajoutons quelques inégalités valides dans la formulation mathématique pour restreindre l'espace des solutions et nous développons une procédure de prétraitement pour réduire la taille du problème.The work presented in this thesis aims to propose methods to solve the multicriteria map sectorization problem in cartography. Firstlly, we have defined the different sectorization problems and we have established the links between these problems with some classical problems which are well studied in the literature : political districting problem, locationallocation problems and constrained graph partitioning problems. Two types of methods have been proposed to solve the sectorization problem. Heuristics have been developed and they compute an optimum Pareto for the different sectorization problems. And for the sectorization problem with predefined centers, we have used a box algorithm and experimented it to find a representation of the Pareto front. The branch and bound method was used to solve optimally the sectorization problem without predefined centers. Before we apply this procedure, we add some valid inequalities in the mathematical formulation for restrict the space of solutions and we develop a preprocessing procedure to reduce the size of the problem.TOURS-Bibl.électronique (372610011) / SudocSudocFranceF

Operational Research IO2017, Valença, Portugal, June 28-30

This proceedings book presents selected contributions from the XVIII Congress of APDIO (the Portuguese Association of Operational Research) held in Valença on June 28–30, 2017. Prepared by leading Portuguese and international researchers in the field of operations research, it covers a wide range of complex real-world applications of operations research methods using recent theoretical techniques, in order to narrow the gap between academic research and practical applications. Of particular interest are the applications of, nonlinear and mixed-integer programming, data envelopment analysis, clustering techniques, hybrid heuristics, supply chain management, and lot sizing and job scheduling problems. In most chapters, the problems, methods and methodologies described are complemented by supporting figures, tables and algorithms. The XVIII Congress of APDIO marked the 18th installment of the regular biannual meetings of APDIO – the Portuguese Association of Operational Research. The meetings bring together researchers, scholars and practitioners, as well as MSc and PhD students, working in the field of operations research to present and discuss their latest works. The main theme of the latest meeting was Operational Research Pro Bono. Given the breadth of topics covered, the book offers a valuable resource for all researchers, students and practitioners interested in the latest trends in this field.info:eu-repo/semantics/publishedVersio

Smart Urban Water Networks

This book presents the paper form of the Special Issue (SI) on Smart Urban Water Networks. The number and topics of the papers in the SI confirm the growing interest of operators and researchers for the new paradigm of smart networks, as part of the more general smart city. The SI showed that digital information and communication technology (ICT), with the implementation of smart meters and other digital devices, can significantly improve the modelling and the management of urban water networks, contributing to a radical transformation of the traditional paradigm of water utilities. The paper collection in this SI includes different crucial topics such as the reliability, resilience, and performance of water networks, innovative demand management, and the novel challenge of real-time control and operation, along with their implications for cyber-security. The SI collected fourteen papers that provide a wide perspective of solutions, trends, and challenges in the contest of smart urban water networks. Some solutions have already been implemented in pilot sites (i.e., for water network partitioning, cyber-security, and water demand disaggregation and forecasting), while further investigations are required for other methods, e.g., the data-driven approaches for real time control. In all cases, a new deal between academia, industry, and governments must be embraced to start the new era of smart urban water systems

Existing and Required Modeling Capabilities for Evaluating ATM Systems and Concepts

ATM systems throughout the world are entering a period of major transition and change. The combination of important technological developments and of the globalization of the air transportation industry has necessitated a reexamination of some of the fundamental premises of existing Air Traffic Management (ATM) concepts. New ATM concepts have to be examined, concepts that may place more emphasis on: strategic traffic management; planning and control; partial decentralization of decision-making; and added reliance on the aircraft to carry out strategic ATM plans, with ground controllers confined primarily to a monitoring and supervisory role. 'Free Flight' is a case in point. In order to study, evaluate and validate such new concepts, the ATM community will have to rely heavily on models and computer-based tools/utilities, covering a wide range of issues and metrics related to safety, capacity and efficiency. The state of the art in such modeling support is adequate in some respects, but clearly deficient in others. It is the objective of this study to assist in: (1) assessing the strengths and weaknesses of existing fast-time models and tools for the study of ATM systems and concepts and (2) identifying and prioritizing the requirements for the development of additional modeling capabilities in the near future. A three-stage process has been followed to this purpose: 1. Through the analysis of two case studies involving future ATM system scenarios, as well as through expert assessment, modeling capabilities and supporting tools needed for testing and validating future ATM systems and concepts were identified and described. 2. Existing fast-time ATM models and support tools were reviewed and assessed with regard to the degree to which they offer the capabilities identified under Step 1. 3 . The findings of 1 and 2 were combined to draw conclusions about (1) the best capabilities currently existing, (2) the types of concept testing and validation that can be carried out reliably with such existing capabilities and (3) the currently unavailable modeling capabilities that should receive high priority for near-term research and development. It should be emphasized that the study is concerned only with the class of 'fast time' analytical and simulation models. 'Real time' models, that typically involve humans-in-the-loop, comprise another extensive class which is not addressed in this report. However, the relationship between some of the fast-time models reviewed and a few well-known real-time models is identified in several parts of this report and the potential benefits from the combined use of these two classes of models-a very important subject-are discussed in chapters 4 and 7

Airspace analysis for greener operations: towards more adoptability and predictability of continuous descent approach (cda)

Continuous Descent Approach (CDA), also known as Optimized Profile Descent (OPD), is the advanced flight technique for commercial aircraft to descend continuously from cruise altitude to Final Approach Fix (FAF) or touchdown without level-offs and with- or near-idle thrust setting. Descending using CDA, aircraft stays as high as possible for longer time thereby expanding the vertical distance between aircraft\u27s sources of noise and ground, and thus significantly reducing the noise levels for populated areas around airports. Also, descending with idle engines, fuel burn is reduced resulting in reduction of harmful emissions to the environment and fuel consumption to air carriers. Due to safety considerations, CDA procedures may require more separation between aircraft, which could reduce the full utilization of runway capacity. Thus, CDA has been limited to low to moderate traffic levels at airports. Several studies in literature have used various approaches to present solutions to the problem of increasing the CDA implementation during periods of high traffic at airports. However, insufficient attention was given to define thresholds that would help Air Traffic Controllers (ATC) to manage and accommodate more CDA operations, strategically and tactically. Bridging this gap is the main intent of this work. This research focus is on increasing CDA operations at airports during high traffic levels by considering factors that impact its CDA adoption as they relate to airports\u27 demographics, and airspace around them {known as terminal maneuvering area (TMA)}. To capture the effect of these factors on CDA Adoptability (CDA-A), in general, and CDA Predictability (CDA-P), at the operational level, two (2) approaches are introduced. The CDA-A model defines and captures the maximum level of traffic threshold for CDA adoption. The model captures the factors affecting CDA in a single measure, which are designated collectively as the Probability of Blocking. It is defined as the fraction of time an aircraft\u27s request to embark on CDA is denied. The denial could emanate from safety concerns as well as other operational conditions, such as the congestion of the stacking space within the TMA. This metric should enhance ATC on the strategic level to increasing CDA operations during possibly higher traffic than normally the case. The other approach is for a CDA-P. This model is developed based on data-driven system approach. It extracts traffic features, such as aircraft type and speed, altitude, and rate of descent; from actual flights data to aid in further operational utilization of CDA in real time. By accurately predicting CDA instances during high traffic at airports, the CDA-P model should assist ATC manage adopting more CDA operations during periods of high demand. Through its framework, the CDA-P model utilizes Feature Engineering and Hierarchal Clustering Analysis, to facilitate descent profile visualization and labeling, for building, training, testing, and validation of CDA predictive models using Decision Trees with AdaBoost and Support Vector Machines (SVM). The CDA-P model is validated using actual flight data operated at Nashville Int\u27l Airport (BNA)

An enhanced fuzzy commitment scheme in biometric template protection

Biometric template protection consists of two approaches; Feature Transformation (FT) and Biometric Cryptography (BC). This research focuses on Key-Binding Technique based on Fuzzy Commitment Scheme (FCS) under BC approach. In FCS, the helper data should not disclose any information about the biometric data. However, literatures showed that it had dependency issue in its helper data which jeopardize security and privacy. Moreover, this also increases the probability of privacy leakage which lead to attacks such as brute-force and cross-matching attack. Thus, the aim of this research is to reduce the dependency of helper data that can caused privacy leakage. Three objectives have been set such as (1) to identify the factors that cause dependency on biometric features (2) to enhance FCS by proposing an approach that reduces this dependency, and (3) to evaluate the proposed approach based on parameters such as security, privacy, and biometric performance. This research involved four phases. Phase one, involved research review and analysis, followed by designing conceptual model and algorithm development in phase two and three respectively. Phase four, involved with the evaluation of the proposed approach. The security and privacy analysis shows that with the additional hash function, it is difficult for adversary to perform brute‐force attack on information stored in database. Furthermore, the proposed approach has enhanced the aspect of unlinkability and prevents cross-matching attack. The proposed approach has achieved high accuracy of 95.31% with Equal Error Rate (EER) of 1.54% which performs slightly better by 1.42% compared to the existing approach. This research has contributed towards the key-binding technique of biometric fingerprint template protection, based on FCS. In particular, this research was designed to create a secret binary feature that can be used in other state-of-the-art cryptographic systems by using an appropriate error-correcting approach that meets security standards

Embracing Analytics in the Drinking Water Industry

Analytics can support numerous aspects of water industry planning, management, and operations. Given this wide range of touchpoints and applications, it is becoming increasingly imperative that the championship and capability of broad-based analytics needs to be developed and practically integrated to address the current and transitional challenges facing the drinking water industry. Analytics will contribute substantially to future efforts to provide innovative solutions that make the water industry more sustainable and resilient. The purpose of this book is to introduce analytics to practicing water engineers so they can deploy the covered subjects, approaches, and detailed techniques in their daily operations, management, and decision-making processes. Also, undergraduate students as well as early graduate students who are in the water concentrations will be exposed to established analytical techniques, along with many methods that are currently considered to be new or emerging/maturing. This book covers a broad spectrum of water industry analytics topics in an easy-to-follow manner. The overall background and contexts are motivated by (and directly drawn from) actual water utility projects that the authors have worked on numerous recent years. The authors strongly believe that the water industry should embrace and integrate data-driven fundamentals and methods into their daily operations and decision-making process(es) to replace established ìrule-of-thumbî and weak heuristic approaches ñ and an analytics viewpoint, approach, and culture is key to this industry transformation