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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
571

Equivalent impedance functions for HVDC converters with inverse cosine control

Bieler, Werner, January 1969 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1969. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
572

Noninformative priors for some models useful in reliability and survival analysis /

Lee, Gunhee, January 1996 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1996. / Typescript. Vita. Includes bibliographical references (leaves 105-108). Also available on the Internet.
573

Noninformative priors for some models useful in reliability and survival analysis

Lee, Gunhee, January 1996 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1996. / Typescript. Vita. Includes bibliographical references (leaves 105-108). Also available on the Internet.
574

Optimal distribution system horizon planning /

Fletcher, Robert Henry, January 2007 (has links)
Thesis (Ph. D.)--University of Washington, 2007. / Vita. Includes bibliographical references (leaves 146-155).
575

Factors that may compromise bulk water distribution reliability

Nel, Daniel Theodorus 05 June 2012 (has links)
D.Ing. / This thesis considers water supply and divides the water supply environment into three categories; the macro water supply environment, the water supply scheme and the consumers. Each of the categories is briefly explored in terms of the factors that may influence it. Subsequently, some of the unique features of a bulk water distribution system are dealt with, as well as different approaches related to bulk water distribution system design and assessment. One of these approaches, the probabilistic approach, offers unique features to assess the reliability of a bulk water distribution system but requires that the probabilistic characteristics of the stochastic events be quantified. The above prompted the goal of this thesis; “…to assess and quantify the probabilistic characteristics of selected factors that may compromise bulk water distribution reliability”. The objectives set and dealt with in this thesis are: • Conducting a literature review that explores uncertainty, reliability, models and techniques, highlighting selected factors that may compromise bulk water distribution reliability, as well as bulk water distribution system water requirements. • Quantifying the probabilistic characteristics of water distribution pipeline failures. • Quantifying the probabilistic characteristics of pipeline failures caused by sinkholes in dolomitic areas. • Quantifying the probabilistic characteristics of power supply failures. This study provides a comprehensive summary of a range of uncertainties that may compromise bulk water distribution reliability. However, the greatest value added corresponds to the following: • It establishes a benchmark related to the probabilistic characteristics of pipeline failures for five pipeline material categories, related to pipeline failure rates and pipeline repair times. • A new methodology is developed in terms of which the probabilistic characteristics of pipeline failures caused by sinkholes in dolomitic areas can be quantified. • It provides a benchmark of the probabilistic characteristics of power supply failures at bulk water distribution pump stations. Proposals are made related to future research needs, divided into two categories: • Complementary research needs that will complement and enhance the work undertaken within this thesis. • Promotional research needs that will promote the practical application of the outcomes generated as part of this thesis.
576

Hyperconnected e-commerce distribution sustainability : multi-agent simulation based assessment for e-vendors

Naccache, Salma 24 April 2018 (has links)
La croissance des chiffres d’affaires issus de la vente en ligne de produits physiques témoigne de l’intérêt des fournisseurs pour l’adoption du e-commerce B2C comme un canal de distribution alternatif à la vente au détail classique. Les retombées positives du B2C sont prônées tant bien au niveau de la littérature scientifique qu’au niveau de la pratique. En effet, l’utilisation des magasins virtuels ayant substitué l’exploitation des magasins conventionnels permet aux e-fournisseurs d’atteindre un large éventail géographique d’une clientèle accessible par Internet. Du côté des consommateurs, l’accessibilité aux produits à tout moment et la livraison à domicile améliorent leur expérience de magasinage, notamment des économies en temps et de carburant. Cette vision commune des retombées de la distribution B2C ne considère que «la face apparente de l’iceberg», confinée à la prise de commande et au dernier kilomètre de livraison. Dans cette thèse, nous nous intéressons à investiguer les impacts de la distribution e-commerce sur une étendue plus large qui englobe le système complet de distribution du e-fournisseur. En effet la complexité de son contexte opérationnel multi-acteur met en épreuve sa capacité à gérer ses opérations de distribution de manière durable, tout en assurant des délais de livraison de plus en plus courts à ses e-consommateurs. D’autant plus, les systèmes de distribution B2C héritent des symptômes d’inefficience observés dans l’environnement logistique actuel. Par ailleurs, le concept de distribution hyperconnectée habilitée par l’Internet Physique (PI ou π) présente une alternative candidate qui à priori permettrait aux e-fournisseurs d’améliorer leurs performances par rapport aux approches actuelles de la gestion de la distribution B2C. Cette thèse développe une étude exploratoire des impacts de l’utilisation de la distribution hyperconnectée habilitée par π sur le potentiel durable de e-fournisseurs, en comparaison avec les options de distribution B2C actuelles. Pour ce faire, des études de cas à base de simulations multiagents ont été développées pour la modélisation de scénarios de distribution d’un e-fournisseur, inspirés des données réelles de notre partenaire industriel Industries de la Rive Sud. L’utilisation d’indicateurs clés de performance nous a permis d’évaluer progressivement les performances du e-fournisseur dans des scénarios portant d’abord sur l’approche de distribution drop-ship. Ensuite nous avons évalué une approche dynamique de déploiement distribué de B2C dans le contexte logistique actuel puis dans un contexte habilité par π. Cette thèse contribue en premier lieu à combler la faille théorique qui existe entre la recherche et la pratique en termes de modélisation des systèmes de distribution B2C intégrée. La deuxième contribution est le développement d’un modèle conceptuel multi-agent générique pour la simulation de scénarios de distribution B2C. La troisième contribution est la proposition d’une approche de consolidation intégrée qui permet aux e-fournisseurs d’améliorer leurs performances tout en réduisant de manière globale les délais de livraison des commandes des e-consommateurs dans le cadre d’une approche de distribution drop-ship. La quatrième contribution est la proposition d’un modèle dynamique d’équilibrage des inventaires dans le réseau de distribution d’un e-fournisseur. La dernière contribution confirme par expériences de simulation qu’une distribution hyperconnectée habilitée par PI permet de renforcer le potentiel durable des e-fournisseurs. / The growth of online sales of physical products demonstrates the interest of suppliers for the adoption of B2C e-commerce as an alternative distribution channel to the conventional retail channel. The benefits of B2C are promoted not only by the scientific literature but also by practically grounded professional literature. In fact, Web stores complemented conventional Brick-and-Mortar retail shops, allowing e-vendors to access a wide geographical range of e-consumers through the Internet. On the consumer side, accessing products at any time and home delivery enhance their shopping experience, notably through time and fuel savings. This common vision of B2C distribution benefits considers only «the visible face of the iceberg», confined to the ordering process and the last-mile delivery. In this thesis, we are interested in investigating the impacts of e-commerce distribution over a larger scope that encompasses the entire distribution system of e-vendors. In fact, the complexity of their multi-actor operational environment challenges their ability to manage their distribution operations in a sustainable way, while ensuring ever quicker deliveries to their e-consumers. Moreover, B2C distribution systems inherit the inefficiency symptoms observed through the current logistics environment. Besides, the concept of the Physical Internet (PI or π) enabled hyperconnected distribution is a priori a candidate alternative that allows e-vendors to improve their performance, in contrast with current B2C distribution approaches. Through an exploratory study, this thesis investigates the impacts of a PI-enabled hyperconnected distribution on the sustainable potential of e-vendors, in contrast with current B2C distribution options. To this end, case studies based on multi-agent simulations were developed for modeling e-vendor distribution scenarios, inspired by actual data from our industrial partner South Shore Industries. Through the use of key performance indicators (KPIs), we gradually assessed e-vendor performance starting from the drop-ship distribution approach. Then, we assessed a dynamic B2C deployment approach in the current logistics environment then in a PI-enabled context. The first contribution of this thesis is to close the theoretical gap between research and practice in terms of modeling integrated B2C distribution systems. The second contribution is the development of a generic multi-agent conceptual model for B2C distribution scenario simulations. The third contribution is the proposal of an integrated consolidation based distribution approach allowing e-vendors to improve their performances, while globally reducing e-consumer order delivery times, within a drop-ship distribution based approach. The fourth contribution is the proposal of an e-vendor dynamic inventory balancing model. The last contribution confirms through a simulation-based experiment, that a PI-enabled hyperconnected distribution leverages the sustainable potential of e-vendors.
577

An Investigation of Distribution Functions

Su, Nan-cheng 24 June 2008 (has links)
The study of properties of probability distributions has always been a persistent theme of statistics and of applied probability. This thesis deals with an investigation of distribution functions under the following two topics: (i) characterization of distributions based on record values and order statistics, (ii) properties of the skew-t distribution. Within the extensive characterization literature there are several results involving properties of record values and order statistics. Although there have been many well known results already developed, it is still of great interest to find new characterization of distributions based on record values and order statistics. In the first part, we provide the conditional distribution of any record value given the maximum order statistics and study characterizations of distributions based on record values and the maximum order statistics. We also give some characterizations of the mean value function within the class of order statistics point processes, by using certain relations between the conditional moments of the jump times or current lives. These results can be applied to characterize the uniform distribution using the sequence of order statistics, and the exponential distribution using the sequence of record values, respectively. Azzalini (1985, 1986) introduced the skew-normal distribution which includes the normal distribution and has some properties like the normal and yet is skew. This class of distributions is useful in studying robustness and for modeling skewness. Since then, skew-symmetric distributions have been proposed by many authors. In the second part, the so-called generalized skew-t distribution is defined and studied. Examples of distributions in this class, generated by the ratio of two independent skew-symmetric distributions, are given. We also investigate properties of the skew-symmetric distribution.
578

The Inverse Problem of Multivariate and Matrix-Variate Skew Normal Distributions

Zheng, Shimin, Hardin, J. M., Gupta, A. K. 01 June 2012 (has links)
In this paper, we prove that the joint distribution of random vectors Z 1 and Z 2 and the distribution of Z 2 are skew normal provided that Z 1 is skew normally distributed and Z 2 conditioning on Z 1 is distributed as closed skew normal. Also, we extend the main results to the matrix variate case.
579

Outliers detection in mixtures of dissymmetric distributions for data sets with spatial constraints / Détection de valeurs aberrantes dans des mélanges de distributions dissymétriques pour des ensembles de données avec contraintes spatiales

Planchon, Viviane 29 May 2007 (has links)
In the case of soil chemical analyses, frequency distributions for some elements show a dissymmetrical aspect, with a very marked spread to the right or to the left. A high frequency of extreme values is also observed and a possible mixture of several distributions, due to the presence of various soil types within a single geographical unit, is encountered. Then, for the outliers detection and the establishment of detection limits, an original outliers detection procedure has been developed; it allows estimating extreme quantiles above and under which observations are considered as outliers. The estimation of these detection limits is based on the right and the left of the distribution tails. A first estimation is realised for each elementary geographical unit to determine an appropriate truncation level. Then, a spatial classification allows creating adjoining homogeneous groups of geographical units to estimate robust limit values based on an optimal number of observations. / Dans le cas des analyses chimiques de sols, les distributions de fréquences des résultats présentent, pour certains éléments étudiés, un caractère très dissymétrique avec un étalement très marqué à droite ou à gauche. Une fréquence importante de valeurs extrêmes est également observée et un mélange éventuel de plusieurs distributions au sein dune même entité géographique, lié à la présence de divers types de sols, peut être rencontré. Dès lors, pour la détection des valeurs aberrantes et la fixation des limites de détection, une méthode originale, permettant destimer des quantiles extrêmes au-dessus et en dessous desquelles les observations sont considérées comme aberrantes, a été élaborée. Lestimation des limites de détection est établie de manière distincte à partir des queues des distributions droite et gauche. Une première estimation par entité géographique élémentaire est réalisée afin de déterminer un niveau de troncature adéquat. Une classification spatiale permet ensuite de créer des groupes dentités homogènes contiguës, de manière à estimer des valeurs limites robustes basées sur un nombre dobservations optimal.
580

Tvorba a řízení marketingových distribučních cest / Creation and management of marketing distribution channels

MRKÁČKOVÁ, Bohdana January 2015 (has links)
This thesis is focused on creating and managing marketing distribution channels in terms of a particular enterprise. The basic concept for this thesis is marketing, from which further depends on other important concepts. The aim is to assess the current creation and management of marketing distribution channels in the selected company. Based on the analysis to propose appropriate measures for improvement. For these purposes, was chosen production company that specializes in the manufacture of doors and door frames.

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