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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.
81

ἄριστον μέν ὕδωρ: URBAN PLANNING AND WATER IN AKRAGAS AND METAPONTO

Vasilodimitrakis-Hart, Seraphina 11 1900 (has links)
This thesis examines the water resource management in two Greek colonies in Magna Graecia, Akragas and Metaponto, and the relationship between resource management and political regimes. It asks how similar ancient urban theory was to the practical reality, and if different forms of government made different provisions for water management. Chapter 1 outlines urban and health theories found in the works of ancient theorists. It debunks the idea that Hippodamos was the inventor of grid planning, while introducing the concept of ‘total’ city planning. The focus of Classical scholarship on Athens necessitates discussions of several Athenian water systems and how resource management changed (or continued) through different governments in Athens as a point of comparison for Akragas and Metaponto. This chapter focuses on literary analysis and introduces the controversial Southeast Fountain House, with an in-depth consideration of the fountain’s naming and dating problems. Chapter 2 contains the case studies of Akragas and Metaponto and an exploration of the hydrogeology at the two sites, with an introduction to the hydrological phenomenon of karst activity. A discussion of their unique water features—the kolymbethra at Akragas and the canals in the chora of Metaponto—connects the deliberate planning that occurred in both cities to Hippodamos and the urban theorists. Chapter 3 more fully explores the role of tyrants and democracies in water management. Regardless of authorship, water resource management and water systems are necessary for any city, and so most tyrannical water infrastructure continued to be used and expanded and improved upon even under different governments. Even under tyranny water management is a provision of the state and is engaged with and managed by the citizens of the city. Water management is an essential part of siting and establishing a city, so that it is inseparable from urban planning. / Thesis / Master of Arts (MA)
82

La gestion de l'eau dans une ville romaine d'Afrique : l'exemple de Thugga (Dougga-Tunisie) / The water management in a Roman city of Africa : the example of Thugga (Dougga-Tunisie)

Garat, Séverine 30 August 2014 (has links)
Ressource naturelle aussi précieuse qu’indispensable à nos sociétés contemporaines que pendant l’Antiquité, l’eau est le point central de ce sujet de doctorat, que nous avons décidé d’aborder sous l’angle de sa gestion par les différents échelons du pouvoir au sein de l’Empire romain mais également au niveau individuel et privé, et cela à travers l’exemple de la ville romaine de Dougga, située en Afrique Proconsulaire, l’actuelle Tunisie. Cette problématique propose ainsi de s’intéresser aux moyens mis en œuvre par les différents niveaux de responsabilités dans le but d’approvisionner et de gérer les besoins en eau d’une importante ville romaine d’Afrique, en se consacrant à l’étude des différents types d’installations hydrauliques. Cette recherche permet de distinguer les techniques de construction et d’identifier les savoir-faire locaux et les influences romaines. Enfin, la confrontation des équipements hydrauliques entre les différents types d’édifices, permet d’évaluer le mode de gestion de l’eau à l’échelle de la ville. / Natural resource as precious and indispensable to contemporary society during ancient times, water is the central topic of this thesis. We decided to address in terms of its management by different levels of power within the Roman Empire but also at individual and private, through the example of the provincial city of Thugga, in Africa Proconsularis, now Tunisia. This issue proposes to focus the resources used by the different levels of responsibilities in order to supply and manage the water needs of an important Roman city of Africa, dedicated to the study of different types of hydraulic structures.
83

Elektrokoagulacioni i adsorpcioni tretmani efluenata u grafičkim procesima ofset štampe / Electrocoagulation and Adsorption Treatments of Effluents in Offset Printing Graphic Processes

Adamović Savka 09 September 2016 (has links)
<p>Predmet doktorske disertacije je uklanjanje neorganskih i organskih polutanata iz efluenata ofset tehnike štampe (otpadnog razvijača i otpadnog sredstva za vlaženje) u cilju minimiziranja njihovog štetnog uticaja na životnu sredinu. Uklanjanje polutanata sprovedeno je primenom elektrokoagulaciono/ flotacionog (EKF) tetmana, adsorpcionog (AD) tretmana i kombinacijom navedenih tretmana. Izvodljivost i efikasnost tretmana analizirana je ispitivanjem uticaja karakterističnih operativnih promenljivih u okviru procesa na smanjivanje količine polutanata. Mehanizmi EKF i AD tretmana definisani su na osnovu teorijskih matematičko kinetičkih modela. Za rešavanje problema odlaganja mulja nastalog nakon EKF tretmana primenjen je solidifikaciono/stabiliza-cioni tretman sa odgovarajućim imobilizacionim agensima. Razvijen je efikasan model kombinacije tretmana efluenata grafičkih procesa ofset štampe kojim je omogućena konverzija efluenata u proizvode kompatibilne sa principima i normativima životne sredine.</p> / <p>The topic of this doctoral dissertation is the removal of inorganic and organic pollutants from the offset printing effluents (waste developer and waste fountain solution) in order to minimize their damaging influence onto the environment. The removal of the pollutants has been performed by electrocoagulation/flotation (ECF) treatment, adsorption (AD) treatment and the combination of the two said treatments. Feasibility and efficacy of the treatments has been analyzed by investigating the effect of characteristic operational variables within the process on the decrease in the quantity of pollutants. The mechanisms of ECF and AD treatments have been defined on the basis of theoretical mathematical-kinetic models. For the solution of the problem of sludge disposal, originating from the ECF treatment, a solidification/stabilization treatment with immobilization agents has been applied. An efficient model that combines the offset printing effluent treatments has been developed, the one which enables the conversion of effluents into products compatible with environmental principles and norms.</p>
84

De l'usage des codes fontaines dans les réseaux de capteurs multisauts / Fountain codes for exploiting diversity in wireless sensor networks

Apavatjrut, Anya 12 July 2011 (has links)
Important sujet de recherche dans les télécommunications contemporaines, les réseaux de capteurs sont des réseaux sans fil constitués de plusieurs nœuds pouvant communiquer entre eux. Chaque capteur est autonome et possède une durée de vie limitée, liée à la taille de sa batterie. Dans ce contexte, l’énergie est une ressource critique qui peut être économisée en minimisant le nombre de paquets émis. De part la nature du médium radio, les données transmises subissent des pertes du canal. La fiabilisation de données dans ce contexte n’est pas simple et devient d’autant plus problématique lorsque la taille de réseau augmente. C’est dans ce contexte que s’inscrit cette thèse qui vise à fournir une technique de fiabilisation des transmissions dans un réseau de capteur. Pour cela, nous proposons de mettre en oeuvre un mécanisme de transmission qui exploite le code fontaine. Ce code est sans rendement et les symboles de redondance sont générés à la volée. Il permet de fiabiliser la transmission avec l’utilisation d’un canal de retour limité. Le code fontaine permet d’alléger le mécanisme de contrôle des transmissions tout en assurant un lien complètement fiable, ce qui permet de réduire la latence et la consommation énergétique d’une transmission. Afin d’optimiser la performance globale du réseau, nous étudions également dans cette thèse le cas où les nœuds sont autorisés à coopérer pour le relayage multi-sauts de paquets destinés à des nœuds distants. Nous montrons dans cette thèse que la technique de codage réseau permet d’introduire de la diversité d’information et ainsi d’améliorer la performance globale de transmissions multi-sauts mono-chemin. Ce résultat a été étendu à la transmission coopérative pour laquelle nous avons à la fois pu exploiter la diversité d’information et la diversité spatiale. / This thesis is dedicated to the deployment of fountain codes and network coding in a wireless sensor network (WSN). A WSN is composed of sensor nodes with restricted capacities : memory, energy and computational power. The nodes are usually randomly scattered across the monitored area and the environment may vary. In the presence of fading, outage and node failures, fountain codes are a promising solution to guaranty reliability and improve transmission robustness. The benefits of fountain codes are explored based on an event-driven WSNet simulator considering realistic implementation based on standard IEEE802.15.4. Fountain codes are rateless and capable of adapting their rate to the channel on the fly using a limited feedback channel. In this thesis, we highlight the benefits brought by fountain code in terms of energy consumption and transmission delay. In addition to the traditional transmission with fountain code, we propose in this thesis to study the network coding transmission scheme where nodes are allowed to process the information before forwarding it to their neighbors. By this means, we can say that packet diversity is exploited as each individual packet is unique and contains different representations of binary data. Redundancy is thus optimized since repetitions are avoided and replaced with diversified information. This can further lead to an overall improved performance in cooperative communication where nodes are allowed to assist in relaying packets from the source the destination. We highlight in this thesis the benefits of fountain code combined to network coding and show that it leads to a reduction in transmission delay and energy consumption. The latter is vital to the life duration of any wireless sensor network.
85

Codage de canal et codage réseau pour les CPL-BE dans le contexte des réseaux Smart Grid / Channel coding and network coding for the CPL-BE in the context of networks Smart Grid

Kabore, Wendyida Abraham 09 March 2016 (has links)
Ce manuscrit traite de la fiabilisation des CPL-BE dans le contexte smart grid avec l’application des techniques de codage correcteur d’erreurs et d’effacements. Après une introduction sur le concept de smart grid, le canal CPL-BE est caractérisé précisément et les modèles qui le décrivent sont présentés. Les performances des codes à métrique rang, simples ou concaténés avec des codes convolutifs, particulièrement intéressants pour combattre le bruit criss-cross sur les réseaux CPL-BE sont simulées et comparées aux performances des codes Reed-Solomon déjà présents dans plusieurs standards. Les codes fontaines qui s’adaptent à n’importe quelles statistiques d’effacements sur le canal CPL sont utilisés et les performances de schémas coopératifs basés sur ces codes fontaines sur des réseaux linéaires multi-sauts sont étudiés. Enfin des algorithmes permettant de combiner le codage réseau et le codage fontaine pour la topologie particulière des réseaux CPL pour les smart grid sont proposés et évalués. / This PhD dissertation deals with the mitigation of the impact of the Narrowband PowerLine communication (NB-PLC) channel impairments e.g., periodic impulsive noise and narrowband noise, by applying the error/erasure correction coding techniques. After an introduction to the concept of smart grid, the NB-PLC channels are characterized precisely and models that describe these channels are presented. The performance of rank metric codes, simple or concatenated with convolutional codes, that are particularly interesting to combat criss-cross errors on the NB-PLC networks are simulated and compared with Reed- Solomon (already present in several NB-PLC standards) codes performance. Fountain codes that can adapt to any channel erasures statistics are used for the NB-PLC networks and the performance of cooperative schemes based on these fountain codes on linear multi-hop networks are studied. Finally, algorithms to combine the network coding and fountain codes for the particular topology of PLC networks for the smart grid are proposed and evaluated.
86

L’expérience de l’eau à travers l’artefact urbain : le cas de Montréal

Candau, Noëmie 12 1900 (has links)
Comme de nombreuses métropoles, la ville de Montréal affronte les défis du réchauffement climatique et de l’urbanisation croissante. Conséquemment, les vagues de chaleur s’intensifient au point de devenir un grave enjeu de santé publique, causant malaises et décès parmi les citadins. Les mesures actuelles de lutte aux ilots de chaleur comprennent l’introduction de végétaux et la diffusion de l’eau. Cette dernière revêt une importance particulière dans le contexte local : Montréal est une île étanche qui s’est progressivement privée de l’accès à ses cours d’eau, constituant pourtant un précieux patrimoine. La conception d’artefacts d’eau (fontaines, bassins, jeux d’eau) pourrait ainsi s’arrimer aux objectifs gouvernementaux d’adaptation aux changements climatiques et d’amélioration des environnements piétons. Cependant, les aménagements actuellement offerts ne semblent pas tous répondre aux besoins actuels des citadins, notamment en matière d’accessibilité et d’inclusion. Le but de cette étude est d’adopter le regard du design industriel centré sur l’humain afin de comprendre comment les artefacts d’eau peuvent offrir des conditions d’expériences positives et inclusives en milieu urbain. Nous nous attacherons d’abord à définir notre vision du design et de l’expérience en adoptant une posture phénoménologique et constructiviste axée sur l’expérience esthétique et l’habitabilité. Nous analyserons notre sujet d’étude selon le concept de la ville à échelle humaine développé par l’architecte Jan Gehl et repris par la ville de Montréal. Ce corpus théorique nous permettra d’explorer les caractéristiques contextuelles, sociales et sensorielles propres aux artefacts d’eau urbains. Une revue de littérature nous permettra d’abord de comprendre comment l’évolution historique des fonctions et des usages liés aux artefacts d’eau influence aujourd’hui leur conception et leur niveau de popularité auprès des citadins. Par la suite, nous observerons et comparerons deux aménagements récents afin d’extraire les qualités pouvant favoriser leur succès. Pour ce faire, nous analyserons les résultats des observations selon trois échelles : 1) l’environnement contextuel et socioculturel du quartier, 2) l’intégration au cadre bâti, et 3) les usagers et leurs interactions avec l’artefact d’eau. Nous souhaitons ainsi étudier l’expérience citadine de l’eau et démontrer la pertinence de l’approche design face aux enjeux de la ville moderne. Nous désirons ainsi informer et sensibiliser les différents acteurs impliqués dans la création d’aménagements aquatiques urbains et, de manière plus générale, contribuer au corpus éclairant l’apport du design à l’espace public. / Like other cities, Montreal is facing global warming and increasing urbanization. As a result, heat waves intensify to the point of becoming a serious public health issue causing discomfort and death among city dwellers. Current measures to mitigate heat islands include greening and spraying water. The latter is particularly critical in the local context: Montreal has become an impervious island gradually disconnecting from its rivers and streams, losing a valuable heritage. The design of water features—like fountains, ponds, water games—could follow policies aimed at adapting to climate change and improving pedestrian environments. However, currently offered water features do not all meet the needs of users, notably in terms of universal accessibility criteria. This study will adopt a user-centred industrial design perspective to better understand how water features can foster positive and inclusive experiences among urban dwellers. We will set our ideas of design and experience by adopting a phenomenological and constructivist approach, using concepts of aesthetic experience and habitability. We will analyze our main subject according to the concept of the Human Scale City developed by architect Jan Gehl and adopted by the city of Montreal. This theoretical corpus will help us understand the contextual, social and sensory characteristics of urban water features. First, a literature review will reveal how the historical evolution of functions and uses related to water features influences their design and popularity nowadays. Then, we will observe and compare two modern fountains to induce which qualities foster their success. In this aim, we will analyze the results of the observations on three scales: 1) the contextual and socio-cultural environment of the neighborhood, 2) the integration to the surrounding built environment, and 3) the users and their interactions with the water feature. Our main goal is to study the urban experience of water and demonstrate the relevance of the design approach to tackle the modern city challenges. Thus, we hope to sensitize the various actors involved in the implementation of urban water features, and more broadly contribute to the corpus on the impact of the design on the public space.
87

Fountain codes and their typical application in wireless standards like edge

Grobler, Trienko Lups 26 January 2009 (has links)
One of the most important technologies used in modern communication systems is channel coding. Channel coding dates back to a paper published by Shannon in 1948 [1] entitled “A Mathematical Theory of Communication”. The basic idea behind channel coding is to send redundant information (parity) together with a message to make the transmission more error resistant. There are different types of codes that can be used to generate the parity required, including block, convolutional and concatenated codes. A special subclass of codes consisting of the codes mentioned in the previous paragraph, is sparse graph codes. The structure of sparse graph codes can be depicted via a graphical representation: the factor graph which has sparse connections between its elements. Codes belonging to this subclass include Low-Density-Parity-Check (LDPC) codes, Repeat Accumulate (RA), Turbo and fountain codes. These codes can be decoded by using the belief propagation algorithm, an iterative algorithm where probabilistic information is passed to the nodes of the graph. This dissertation focuses on noisy decoding of fountain codes using belief propagation decoding. Fountain codes were originally developed for erasure channels, but since any factor graph can be decoded using belief propagation, noisy decoding of fountain codes can easily be accomplished. Three fountain codes namely Tornado, Luby Transform (LT) and Raptor codes were investigated during this dissertation. The following results were obtained: <ol> <li>The Tornado graph structure is unsuitable for noisy decoding since the code structure protects the first layer of parity instead of the original message bits (a Tornado graph consists of more than one layer).</li> <li> The successful decoding of systematic LT codes were verified.</li> <li>A systematic Raptor code was introduced and successfully decoded. The simulation results show that the Raptor graph structure can improve on its constituent codes (a Raptor code consists of more than one code).</li></ol> Lastly an LT code was used to replace the convolutional incremental redundancy scheme used by the 2G mobile standard Enhanced Data Rates for GSM Evolution (EDGE). The results show that a fountain incremental redundancy scheme outperforms a convolutional approach if the frame lengths are long enough. For the EDGE platform the results also showed that the fountain incremental redundancy scheme outperforms the convolutional approach after the second transmission is received. Although EDGE is an older technology, it still remains a good platform for testing different incremental redundancy schemes, since it was one of the first platforms to use incremental redundancy. / Dissertation (MEng)--University of Pretoria, 2008. / Electrical, Electronic and Computer Engineering / MEng / unrestricted
88

Индикатори старења средства за влажење у офсет штампи / Indikatori starenja sredstva za vlaženje u ofset štampi / The indicator of fountain solution aging in offset printing

Oros Ivana 07 October 2015 (has links)
<p>Истраживање старења средства за влажење у реалним условима током 8-часовног радног времена у процесу офсет штампе је омогућило сагледавање критичних фактора деактивације средства за влажење и представља основ за праћење кинетике структурних и физичко-хемијских промена активних компоненти средства за влажење. Такође, истраживање обезбеђује и дефинисање могућих механизама хемијских процеса који условљавају пад активности присутних компоненти средства за влажење током процеса старења.</p> / <p>Istraživanje starenja sredstva za vlaženje u realnim uslovima tokom 8-časovnog radnog vremena u procesu ofset štampe je omogućilo sagledavanje kritičnih faktora deaktivacije sredstva za vlaženje i predstavlja osnov za praćenje kinetike strukturnih i fizičko-hemijskih promena aktivnih komponenti sredstva za vlaženje. Takođe, istraživanje obezbeđuje i definisanje mogućih mehanizama hemijskih procesa koji uslovljavaju pad aktivnosti prisutnih komponenti sredstva za vlaženje tokom procesa starenja.</p> / <p>The investigation of fountain solution aging in real condition during 8-hr<br />working shift of offset printing process allows an overview of the critical<br />factors of fountain solution deactivation and represents the basis for<br />monitoring the structural and physico-chemical changes of active<br />components of fountain solution. Also, the investigation defines the possible<br />mechanism of chemical processes which cause the decreasing of activity of<br />present components in fountain solution during aging process.</p>
89

The Rebirth Of Consciousness

Blaszak, Urszula 01 January 2007 (has links) (PDF)
Human beings encounter cascades of a plethora of experiences, one after another, every single microsecond of our lives. There are many things happening around. The world is full of events and occurrences. As they happen, the mind reacts to every individual input. This is a very exhausting and difficult. Thus, people have developed a process of self-defense against this horrible mishmash of information. Their minds have this amazing capacity of sorting them out and making sense out of them. Humankind's survival depends on that. If one does not sort all this information out, one might not be able to make a simplest decision. As humans process the information, they learn to ignore and forget. They focus on their feelings and emotions. They forget the logic. The oversimplification process begins. Humans create rigid systems of oversimplified formulas. They assign adjectives to things, occurrences, and other people. The number of those adjectives is small. After assigning, those adjectives obscure everything else. A new world is created, stupid, limited, lazy, and in the end making humans very easy to control. What starts as a basic survival process ends up as a tool one can use to destroy the owners of the mind. In the end, the birth of consciousness leads to its death. My work fights this process. It aims to put a person back into that state of shock created by a mishmash of information and thus create the rebirth of consciousness.
90

Diel Temperature and Dissolved Oxygen Patterns in Sites with and without Planktonic Life Stage of Thompsodinium intermedium in Comal Springs, TX

Gilpin, Cheryl 2012 May 1900 (has links)
Between July 2009 and October 2011, a new habitat was found for a rarely reported freshwater dinoflagellate species, Thompsodinium intermedium - Comal Springs (Comal County), Texas. In 2011, diel in-situ monitoring in monospecific blooms of this species revealed previously undetected negative impacts on endangered species habitat availability associated with conditions of low flow levels, recorded at the U.S. Geological Survey gage # 08169000 on Texas Commission on Environmental Quality river segment 1811 station 12655. During a period of low springflow in the summer of 2011, late afternoon and early morning measurements of dissolved oxygen and temperature and presence of dinoflagellate blooms were monitored at six sites. Significant differences in diel fluctuations were found in all of these parameters among sites with and without the planktonic blooms. These fluctuations increased risk of hypoxia and hyperthermia conditions at sites of planktonic bloom events. Arrays of in-situ continuous monitoring temperature/light probes were used inside and outside of blooms. Wildlife and human health implications are that hypoxia and hyperthermia are known to promote conditions favorable to harmful microbes which may be transported from springs to coastal bays. In-situ data demonstrated that T. intermedium blooms, hypoxia, and hyperthermia occurred in the upper Comal headwaters. These natural environmental stressors may be avoidable if adequate springflows are maintained to buffer against these impacts.

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