Distribution System

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Managing the impact of changing treatment practices on distribution system water quality

Managing the impact of changing treatment practices on distribution system water quality

All physical, chemical and microbiological processes that take place in the distribution system are related in some way to the quality of the distributed water. Over a period of usage, source-water will establish an apparent equilibrium of physico- chemical and biological reactions in the distribution system. This apparent equilibrium makes it possible to predict and maintain a specific quality for the water being distributed. Recent trends in source-water diversification, regulatory restrictions and demand dynamics may result in distribution systems receiving variable water quality. This variability results in temporal water quality changes, where rates of change may be either gradual or sudden, depending upon operational conditions. Any change in the finished water quality will disrupt the existing equilibrium, resulting in a transitional state until a new equilibrium is reached. This new equilibrium may either improve or deteriorate the water quality at the consumers tap (Taylor et al. 2005). Distribution systems that historically saw a single source supply often have problems maintaining distributed water quality when alternate sources are introduced (Lovins, III et al. 2005; Taylor et al. 2005).
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Interpreting drinking water quality in the distribution system using Dempster-Shafer theory of evidence

Interpreting drinking water quality in the distribution system using Dempster-Shafer theory of evidence

1 Institute for Research in Construction, National Research Council, Ottawa, ON, Canada, K1A 0R6 2 Département d’Aménagement, Université Laval, Québec City, QC, Canada, G1K7P4 Abstract Interpreting water quality data routinely generated for control and monitoring purposes in water distribution systems is a complicated task for utility managers. In fact, data for diverse water quality indicators (physico-chemical and microbiological) are generated at different times and at different locations in the distribution system. To simplify and improve the understanding and the interpretation of water quality, methodologies for aggregation and fusion of data must be developed. In this paper, the Dempster-Shafer theory also called theory of evidence is introduced as a potential methodology for interpreting water quality data. The conceptual basis of this methodology and the process for its implementation are presented by two applications. The first application deals with the interpretation of spatial water quality data fusion, while the second application deals with the development of water quality index based on key monitored indicators. Based on the obtained results, the authors discuss the potential contribution of theory of evidence as a decision-making tool for water quality management.
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2016 — An impedance based method for distribution system monitoring

2016 — An impedance based method for distribution system monitoring

mathematics needed for mapping monitoring zone from P-Q plane onto the R-X plane. It used to detect power factor variations and active and reactive power flows beyond the pre- defined limits. In addition, it will be shown that based on the proposed transformation, any complex monitoring zone in the P-Q plane can be transferred to the R-X plane. The dynamic performance of the proposed method is studied with the unbalanced IEEE 8500 node test feeder, for on-line monitoring of the reactive power capability requirement proposed by the Alberta Electric System Operator (AESO) (Ellis et al., 2012) for a wind farm integrated to the system.This chapter is organized as follows: in Section 3.2 the necessity of distribution system monitoring will be explained. Section 3.3 describes the mathematic relationship between the active and reactive power flows and the measured impedance trajectories. Section 3.4 presents the IEEE 8500 node test feeder as case study and the simulation results will be presented in Sections 3.5 and 3.6. Finally the conclusion is presented in Section 3.7.
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Network design of a multi-period collaborative distribution system

Network design of a multi-period collaborative distribution system

Several practical and theoretical extensions can be proposed to this work. As far as theoretical extensions are concerned, the model could include heterogeneous fleet on each route and be reinforced by valid inequalities (note that the disjunctive and districting constraints are not valid inequalities). Several theoretical extensions could also be moti- vated by practical considerations. First, setting or modifying a complex logistics network is generally a long process that cannot be implemented at once. All decisions can be reg- ularly revised. In particular, RDC locations can be revised for example at the end of each transportation contract with the carriers, in case of commercial development in some new regions or if new partners join the coalition. This flexibility is made possible since the whole distribution system is subcontracted: the suppliers do not buy any facility, but only logistics and transportation services. This suggests dynamic facility location models that represent the deployment of a logistics network over several years. Another motivation for defining multi-periodic models is the possible introduction of flexibility in the network, with the existence of seasonal RDCs that are used only during specific seasons of each year. A slight adaptation of the model would be to propose FTL routes visiting one or two intermediate RDCs. Finally, the current model is considered deterministic although it uses uncertain data. Solving a stochastic model with uncertain future demand was not possible in practice due to the difficulty of modeling demand uncertainty. However, we think this is a challenging perspective both from a theoretical and practical point of view.
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Modeling of heterotrophic bacteria in a water distribution system

Modeling of heterotrophic bacteria in a water distribution system

the quantitative analysis of the impact on HPC of each single factor is not sufficient to identify the most critical variables at stake. Multivariate approaches for data analysis must therefore be favored to identify such variables. Multivarite models were developed to explain and predict the occurrence of heterotrophic bacteria based on the database described previously. The application of multivariate models permits the consideration of autocorrelation between explanatory variables. Two types of models were applied: logistic regression and negative binomial models. The first allow for modeling the presence or absence of an event (in this case, samples with negative or positive results for samples for HPC). The second is a method adapted to model rare events (in this case, quantitative results of HPC in samples). For the logistic regression model, three variables were identified as significantly influencing the presence of heterotrophic bacteria in the DS under study (table 2). According to the model, the level of free residual chlorine is the most critical variable which controls the presence of heterotrophic bacteria (higher Wald, negative association, B < 0). Water temperature and absorbance were also significant variables, but less so than residual chlorine. Other water quality variables (turbidity, pH) and operational characteristics (type of distribution system) were not significant in this model.
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Analysis of various all-electric-ship electrical distribution system topologies

Analysis of various all-electric-ship electrical distribution system topologies

physics-based environment to perform fully-integrated sim- ulation of electrical, hydrodynamic, thermal, and structural components of the ship operating in a seaway. The goal of this architectural model is to develop an early-stage design tool capable of performing tradeoff studies under a standardized set of metrics. In the past we have used this model to compare a medium-voltage DC electrical distribution system to a hybrid DC/AC electrical distribution system, analyzing the effects on weight, volume and efficiency under a maximum loading condition [1]. We also used the model to investigate the effects of new propeller and motor designs such as a high-speed propeller or a contra-rotating propeller/motor combination [2]. Continued expansion of this model allows us to address a wider range of problems. We now run the model through a typical operational scenario, thus comparing topologies through a range of electrical loading schemata. In addition, we have added a survivability analysis metric.
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Achieving Reusability in Visual Simulation of a Parts Distribution System

Achieving Reusability in Visual Simulation of a Parts Distribution System

The purpose of this paper is to illustrate component- based visual simulation model development using the Visual Simulation Environment TM (VSE) software product. Two libraries are presented: clock library and distribution library. The clock library provides reusable model components for representing date and time in the Gregorian calendar. The distribution library provides reusable model components for simulating parts distribution systems. We have developed a VSE model of a parts distribution system of a local company in Blacksburg, Virginia, by way of reusing from the clock and distribution libraries. The simulation project illustrated the value and importance of component-based model develop- ment under the object-oriented paradigm.
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The effectiveness of the Swiss and Canadian antibiotic distribution system compared

The effectiveness of the Swiss and Canadian antibiotic distribution system compared

SJ: What would be the biggest challenges in changing the antibiotic system? DCP: The logistic aspect also has to be taken into consideration, especially for the pharmacist, what he will have to put in place in order to change the distribution system like in Canada. If the distribution system changes that would mean that the pharmacies would not only be a dispensing unit but would also turn into a production site as they have to prepare the exact number of pills, stick the label on it and inform the patient. The pharmacist is the only one allowed to do that, the logistical aspect is therefore immense. Therefore only a few pharmacies in Switzerland still produce some preparation onsite. All this has to be done under very strict regulations. Switzerland has stricter regulations compared to other countries. The producing pharmaceutical company tries to find right packaging, the authorities try to control the packaging needed are available and the OFSP will only refund packaging that make sense for prescription only. Canadian and US pharmacies probably have a certain infrastructure in place for this kind of distribution system that Switzerland has not, which would be a major change for the Swiss system. The major problem in Switzerland is that the leaflet is mandatory, this is not the case for Canada or the US. A leaflet has to be with every sold medication. Leaflet will give information for the patients; however, dosage and treatment lengths will not be available in the leaflet. The information for professionals will be at swissmedic where posology can be found. Dosage might depend on the age and weight of the patients or if the doctor estimates a longer treatment is making more sense. Prescribed treatment will also depend on the severity of the illness, the age and the weight of the patient
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Aggregated Dynamic Equivalent of a Distribution System hosting Inverter-based Generators

Aggregated Dynamic Equivalent of a Distribution System hosting Inverter-based Generators

Abstract—An equivalent, i.e. a reduced-order model, of active distribution networks is derived, for use in (phasor-mode) dy- namic simulations of large-disturbances. In the unreduced model, the network hosts a large number of inverter-based generators, responding to the disturbances in accordance with recent or near- future grid codes. The aggregated equivalent is of the “grey-box” type and its parameters are tuned in the least-square sense to match the dynamic responses of the unreduced system to several training disturbances. Changes in operating point are easily reflected when initializing the reduced model. Simulations are reported on a detailed 75-bus distribution system. The accuracy of the equivalent has been checked with respect to untrained disturbances and changes of the operating point.
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A MODELLING FRAMEWORK FOR PROCUREMENT OF A RETAIL DISTRIBUTION SYSTEM WITH ECONOMIC AND ENVIRONMENTAL GOALS

A MODELLING FRAMEWORK FOR PROCUREMENT OF A RETAIL DISTRIBUTION SYSTEM WITH ECONOMIC AND ENVIRONMENTAL GOALS

major concern for the retail industry. In order to support a retail company to optimize its procurement policy and coordination with its suppliers at the tactical planning level, we propose a multi-periodic, multi-product modeling framework for a three-level distribution system encompassing the suppliers, intermediate platforms and distribution centers. Different procurement and transport policies may be undertaken between the entities, such as direct shipment from the suppliers to the distribution centers or shipment through intermediate platforms. We have designed a generic MIP (Mixed Integer Programming) model with two objective functions to be considered (total shipment and storage cost, or CO2 emissions from transport). Solutions will be obtained using realistic data provided by a major French retail company.
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Self-Adaptive Distribution System State Estimation

Self-Adaptive Distribution System State Estimation

One characteristic of the Smart Grid is its ability to control itself. To do this, papers in literature suggest that the state of the controlled network should be estimated. This paper proposes an agent-based architecture to enable the transi- tion to the Smart Grid, a design and an implementation of agent behav- iors aiming at solving the State Estimation problem. Based on the Adap- tive Multi-Agent System theory, the developed system allows from local interactions between agents to estimate in a reasonable time and com- putational complexity the state of a distribution system.
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The High Voltage distribution system of the ATLAS Tile Calorimeter and its performance during data taking

The High Voltage distribution system of the ATLAS Tile Calorimeter and its performance during data taking

2 The Tile Calorimeter The TileCal calorimeter is described extensively in several publications [ 1 , 2 , 5 ], only the information relevant to the HV distribution system is given here. The calorimeter is a large cylinder with the LHC beam as axis, mechanically divided into three parts: the central part, called Long Barrel (LB) and two end-caps, the Extended Barrels (EBA and EBC). Each of these three barrels is assembled from 64 wedge-shaped modules (see Fig. 1 ), labeled from 01 to 64. The modules have a periodical structure of iron plates and scintillating tiles, the tiles being perpendicular to the beam axis. Wavelength shifting fibres transmit light produced in the tiles to 9852 photomultipliers [ 6 ]: except in some exceptionnal cases, each tile is read out by two fibres, from both sides (left and right). In each module a three-dimensional cell structure is defined by grouping several optical fibres connected to the same PMT [ 7 ]: two photomultipliers (for left and right fibres) read-out each cell and the signals of the two PMTs are summed up to provide the cell response (except for a few special cases, when a single PMT is connected to the cell).
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Self-Adaptive Distribution System State Estimation

Self-Adaptive Distribution System State Estimation

One characteristic of the Smart Grid is its ability to control itself. To do this, papers in literature suggest that the state of the controlled network should be estimated. This paper proposes an agent-based architecture to enable the transi- tion to the Smart Grid, a design and an implementation of agent behav- iors aiming at solving the State Estimation problem. Based on the Adap- tive Multi-Agent System theory, the developed system allows from local interactions between agents to estimate in a reasonable time and com- putational complexity the state of a distribution system.
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Convex Models of Distribution System Reconfiguration

Convex Models of Distribution System Reconfiguration

V. S UMMARY AND FUTURE WORK We have introduced three new convex, mixed-integer pro- gramming models for distribution system reconfiguration, im- plicit in which are new approximations to power flow in radial networks. To the authors’ knowledge, these models are the first AC formulations that can utilize a powerful class of convex optimization algorithms. On two examples, the quadratic programming model is by far the most efficient, yet also obtains good solutions, evidencing its practicality for very large systems. The second-order cone model appears to be slightly more reliable in producing good solutions, but is rather expensive computationally; it is however reasonable to expect substantial improvements in mixed-integer second-order cone programming algorithms in the near future, in which case the second-order cone and quadratically constrained programming models will become more scalable options. An additional appealing aspect of each model is the convenience of using established commercial software, the scalability of which can be enhanced by relaxing optimality criteria; we remark, however, that although we recommend the use of such tools, any algorithm may be used to solve these models, and will still benefit from their convexity.
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Integration of renewable energies in the electricity distribution system

Integration of renewable energies in the electricity distribution system

1 I N T R O D U C T I O N This introduction will be organized in the following manner. First we will describe the various phases of the evolution of the French power system, from the decentralized system of the early days to the large-scale deregulated current system and passing through the state- owned monopoly. We will focus particularly on the interplay between technological improvements and political orientations as the deter- mining factor explaining power system organization and functioning. Subsequently we introduce a potentially disruptive set of technolo- gies that is the focus of this thesis: distributed generation, with a specific attention brought to the complementary instances of weather- dependent renewable generators and storage. Due to intrinsic quali- ties that we set forth, renewable energies have enjoyed a broad politi- cal support that has turned into various subsidy mechanisms that we also present. In turn, the development that this has spurned will have possibly adverse impacts on the rest of the power system that we de- pict in detail. Distributed storage units, their characteristics and the applications they could have in the context of large distributed renew- able generation penetration are specified next. Due to this expected expansion of distributed generation, the assumptions underpinning the current planning and operation of the power system, and espe- cially the distribution system, are called into question. To cope with this, various strategies relying on differing assumptions concerning the level of control and observability of the future distribution net- work have been put forward in the literature. After describing them summarily, we identify a potential area of improvement that leads us to set out the list of objectives that we have assigned ourselves as well as the organization of the rest of this contribution.
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Représentation du territoire national et circulation des grains : le Système de distribution publique indien Representation of national territory and grain circulation: the Public Distribution System in India

Représentation du territoire national et circulation des grains : le Système de distribution publique indien Representation of national territory and grain circulation: the Public Distribution System in India

Frédéric Landy Professeur de géographie Résumé En Inde, la pesante machine du Système de distribution publique (PDS) qui redistribue à prix subventionnés le grain ou le sucre achetés dans les zones de surproduction connaît de nombreux dysfonctionnements. Impératifs sociaux, soucis productivistes, intérêts illicites, nombreux sont les facteurs expliquant son maintien dans une Inde qui pourtant connaît de profondes réformes libérales. Il en est un autre : dans son idéal, le PDS correspond en effet à deux représentations du territoire national qui se superposent en grande partie. La territorialité hindoue et son interprétation par la droite nationaliste, fondées sur les points cardinaux et sur leurs liaisons, tout comme la territorialité moderniste nehruvienne, fondée sur le souci d’intégration par des flux économiques, correspondent toutes à une conception de l’espace national basée sur la circulation, et qui concordent donc pour maintenir l’existence du PDS.
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Damage to water distribution system caused by the 1995 Hyogo-Ken Nanbu earthquake

Damage to water distribution system caused by the 1995 Hyogo-Ken Nanbu earthquake

Figure 4 shows a joint failure of a 800 rnrn ductile iron pipe in slip-out mode, Figure 5 shows the failure of a 800 mm cast iron pipe in fracture mode, The break rates with respect to t[r]

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Matrix approach based on Quadripole for quality analysis in Aircraft Electrical Power Distribution System

Matrix approach based on Quadripole for quality analysis in Aircraft Electrical Power Distribution System

5. quality analysis based on power quality standards Civil and military aircraft manufacturers define standards, such as the MIL-STD-704 for military aircraft, in order to maintain the power quality of AC and DC electric power network and to ensure interoperability at system level. These standards set the interface between sources and loads to ensure compatibility between the aircraft electric system, external power, and airborne utilization equipment. Therefore, it give designers the specifications that they need to respect in order to ensure that an airborne system will be compatible with the power supply provided by the aircraft manufacturer.
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Analysis of a manufacturing and distribution system

Analysis of a manufacturing and distribution system

In addition, Autogear holds a strong market share with aftermarket customers (greater than 50 percent of aftermarket customers (operators) chose Autogear for their steel fri[r]

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Water quality in the distribution system

Water quality in the distribution system

L’accès à ce site Web et l’utilisation de son contenu sont assujettis aux conditions présentées dans le site LISEZ CES CONDITIONS ATTENTIVEMENT AVANT D’UTILISER CE SITE WEB.. READ THESE [r]

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