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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.
101

Développement d'un procédé innovant de retraitement des slurries de l'industrie microélectronique

Testa, Fabrice 18 July 2011 (has links)
L’objectif de cette étude est de recycler du slurry, suspension silicatée, utilisé dans le domaine de l’électronique lors du polissage. Deux applications de polissage sont étudiées : le polissage silicium et le polissage tungstène. Pour ces deux applications, une caractérisation physico-chimique des slurries en amont et en aval du procédé de polissage a mis en exergue une importante dilution du slurry par de l’eau déionisée destinée au rinçage des wafers : une collecte ségrégée a ainsi été mise en place. Le procédé d’ultrafiltration permet une reconcentration de la silice. Toutefois ce procédé ne permet pas la récupération des composés dissous du slurry, qui restent pourtant essentiels au polissage et d’autant plus pour l’application tungstène : un ajustement chimique est donc développée avant réutilisation du slurry ainsi retraité. Pour le slurry tungstène, la matrice chimique étant plus complexe, deux types d’ajustement ont été testés dont les proportions ont été optimisées par une méthode de plans d’expériences.Concernant le slurry silicium, un prototype industriel a été installé et les résultats de polissage sont similaires au slurry POU sur un nombre significatif de plaques. La qualification industrielle a été réalisée. Ce prototype permet d’atteindre les objectifs de diminution de 30% de la consommation de slurry et de 40% des volumes d’effluents rejetés vers station d’épuration. / The chemical and mechanical polishing is a costly step in the process of microelectronic chips manufacturing. This study aims for recycle the silicate suspension named slurry by membrane processes. Both polishing applications are studied: the silicium and the tungsten polishing. A physical and chemical characterization before and after polishing process shows an important dilution of slurry by deionized water used for wafers rinsing. From CMP machine, a collect segregation of a concentrated effluent is realised by a diverter valve. Ultrafiltration has been chosen to reconcentrate silica but does not permit to recover the chemical compounds of the slurry which are essential to the polishing mainly to the tungsten application. Thus, retreatment process includes a collect segregation at the CMP outlet to decrease the dilution factor of slurry, an ultrafiltration step to concentrate silica and a chemical adjustment step. About tungsten application, the chemical media is more complex and two types of adjustment have been led. Firstly, a mix of POU and retreated slurry has been tested and secondly, an experiment of design with three important compounds of the slurry has been tested. Most CMP parameters are obtained in industrial specifications with the mix of POU and retreated slurry.Concerning the silicium slurry, an industrial prototype is installed and polishing results are similar to the original slurry for a significant wafers number. The industrial agreement is obtained. This prototype allows reaching a 30% decrease of slurry consumption and a 40% decrease of waste waters.
102

Extending higher-order logic with predicate subtyping : application to PVS / Extension de la logique d'ordre supérieur avec le sous-typage par prédicats : application à PVS

Gilbert, Frédéric 10 April 2018 (has links)
Le système de types de la logique d'ordre supérieur permet d'exclure certaines expressions indésirables telles que l'application d'un prédicat à lui-même. Cependant, il ne suffit pas pour vérifier des critères plus complexes comme l'absence de divisions par zéro. Cette thèse est consacrée à l’étude d’une extension de la logique d’ordre supérieur appelée sous-typage par prédicats (predicate subtyping), dont l'objet est de rendre l'attribution de types aussi expressive que l'attribution de prédicats. A partir d'un type A et d'un prédicat P(x) de domaine A, le sous-typage par prédicats permet de construire un sous-type de A, noté {x : A | P(x)}, dont les éléments sont les termes t de type A tels que P(t) est démontrable. Le sous-typage par prédicats est au coeur du système PVS.Ce travail présente la formalisation d'un système minimal incluant le sous-typage par prédicats, appelé PVS-Core, ainsi qu'un système de certificats vérifiables pour PVS-Core. Ce deuxième système, appelé PVS-Cert, repose sur l'introduction de termes de preuves et de coercions explicites. PVS-Core et PVS-Cert sont munis d'une notion de conversion correspondant respectivement à l'égalité modulo beta et à l'égalité modulo beta et effacement des coercions, choisi pour établir une correspondance simple entre les deux systèmes.La construction de PVS-Cert est semblable à celle des PTS (Pure Type Systems) avec paires dépendantes et PVS-Cert peut être muni de la notion de beta-sigma-réduction utilisée au coeur de ces systèmes. L'un des principaux théorèmes démontré dans ce travail est la normalisation forte de la réduction sous-jacente à la conversion et de la beta-sigma-réduction. Ce théorème permet d'une part de construire un algorithme de vérification du typage (et des preuves) pour PVS-Cert et d'autre part de démontrer un résultat d'élimination des coupures, utilisé à son tour pour prouver plusieurs propriétés importantes des deux systèmes étudiés. Par ailleurs, il est également démontré que PVS-Cert est une extension conservative du PTS lambda-HOL, et qu'en conséquence PVS-Core est une extension conservative de la logique d'ordre supérieur.Une deuxième partie présente le prototype d'une instrumentation de PVS pour produire des certificats de preuve. Une troisième et dernière partie est consacrée à l'étude de liens entre logique classique et constructive avec la définition d'une traduction par double négation minimale ainsi que la présentation d'un algorithme de constructivisation automatique des preuves. / The type system of higher-order logic allows to exclude some unexpected expressions such as the application of a predicate to itself. However, it is not sufficient to verify more complex criteria such as the absence of divisions by zero. This thesis is dedicated to the study of an extension of higher-order logic, named predicate subtyping, whose purpose is to make the assignment of types as expressive as the assignment of predicates. Starting from a type A and a predicate P(x) of domain A, predicate subtyping allows to build a subtype of A, denoted {x : A | P(x)}, whose elements are the terms t of type A such that P(t) is provable. Predicate subtyping is at the heart of the proof system PVS.This work presents the formalization of a minimal system expressing predicate subtyping, named PVS-Core, as well as a system of verifiable certificates for PVS-Core. This second system, named PVS-Cert, is based on the introduction of proof terms and explicit coercions. PVS-Core and PVS-Cert are equipped with a notion of conversion corresponding respectively to equality modulo beta and to equality modulo beta and the erasure of coercions, chosen to establish a simple correspondence between the two systems.The construction of PVS-Cert is similar to that of PTSs (Pure Type Systems) with dependent pairs and PVS-Cert can be equipped with the notion of beta-sigma-reduction used at the core of these systems. One of the main theorems proved in this work is the strong normalization of both the reduction underlying the conversion and beta-sigma-reduction. This theorem allows, on the one hand, to build a type-checking (and proof-checking) algorithm for PVS-Cert and, on the other hand, to prove a cut elimination result, used in turn to prove important properties of the two studied systems. Furthermore, it is also proved that PVS-Cert is a conservative extension of the PTS lambda-HOL and that, as a consequence, PVS-Core is a conservative extension of higher-order logic.A second part presents the prototype of an instrumentation of PVS to generate proof certificates. A third and final part is dedicated to the study of links between classical and constructive logic, with the definition of a minimal double-negation translation as well as the presentation of an automated proof constructivization algorithm.
103

GENIAC – Konfigurieren komplexer Produktsimulationen mit Hilfe von natürlichen Benutzeroberflächen

Wegner, Michael, Freitag, Georg, Wacker, Markus 25 September 2017 (has links)
Mit der zunehmenden Bedeutung von virtuellen Prototypen in den frühen Phasen der Produktentwicklung wachsen ebenso die an die verwendeten Softwarelösungen gestellten Anforderungen. Sollen unterschiedliche Faktoren wie Funktionalität, Design oder auch Ergonomie getestet werden, so muss die verwendete Software Module bereitstellen, welche die Erstellung von ganzheitlichen Produktmodellen ermöglichen. Zu den benötigten Modulen zählen zum Beispiel Simulation, Grafik, Eingabeschnittstellen oder Sound. Mit der steigenden Komplexität der zu erstellenden Prototypen wächst jedoch auch der Aufwand für die Entwickler und Anwender, sich in diese einzuarbeiten, diese zu konfigurieren und zu verwalten. An dieser Stelle setzt das Forschungsprojekt GENIAC an. Sein Ziel ist es, die Konfiguration von hochkomplexen Software-Frameworks mit Hilfe natürlicher Benutzeroberflächen zu vereinfachen. Hierzu werden die zu untersuchenden Konfigurationen als Netzwerke auf großflächigen Multi-Touch Bildschirmen dargestellt und mittels natürlicher Gestensteuerung bearbeitet.
104

Moving the museum outside its walls : An Augmented Reality Mobile Experience

Marshall, Tommy January 2011 (has links)
This thesis project examines how to design an Android application that uses augmented reality to help users navigate in the City of Stockholm. The main users of the application are assumed to be first time visitors to Stockholm. The thesis project concerns design, technologies, and usability issues - while focusing on how to design a suitable application. The application will maybe be used by the Nobel Museum to offer information, and assistance to tourists who are looking for and visiting different locations connected with the Nobel Prize. The focus will be to achieve an easy to use system for these users, as the user will not be able to get support after leaving the museum. The application is meant to be distributed as freeware that will contribute to a positive experience by museum visitors. One of the aims is that the users should find the application appealing, motivating them to learn more about the Nobel Prize following their visit to the Nobel Museum. For tourists this means that they get the possibility to experiencing Stockholm in a new way, where information is stored at different locations. They get a guided tour of Stockholm without a guide, they can take the time they want. The museum gets the possibility to spread their message about the Nobel Price around in Stockholm in a new and exciting way. With the use of technology it is possible to spread the museum experience outside its walls, which will be shown in this report. / Det här examensarbetet undersöker hur man kan designa en Android-applikation somanvänder förstärkt verklighet för att hjälpa användare navigera i Stockholms stad. Denhuvudsakliga användaren antas vara förstagångsbesökare i Stockholm.Examensarbetet avser design, teknik och användarvänlighet - med fokus på hur man utformaren lämplig applikation. Applikationen kommer eventuellt att användas av Nobelmuseetför att erbjuda information och hjälp turister som är intresserade av olika platser som ärrelaterade till Nobelpriset.Fokus kommer vara att uppnå ett lättanvänt system för dessa användare. Användarenkommer inte kunna fånågot stöd efter att de lämnat museet. Applikationen är tänkt att delasut som freeware, som bidrar till en positiv upplevelse för museets besökare. Ett av syftena äratt användarna ska anse att applikationen är intressant och motivera dem att lära sig mer om Nobelpriset efter deras besök på Nobelmuseet.För turister innebär detta att de får möjlighet att uppleva Stockholm på ett helt nytt sättdär information lagras på olika platser. De får en guidad tur i Stockholm som sker utan enguide, de kan ta den tid de vill. Museet får möjlighet att sprida sitt budskap om Nobelprisetrunt i Stockholm på ett nytt och spännande sätt. Med hjälp av teknik är det möjligt att spridamuseiupplevelse utanför dess område, som kommer att visas i denna rapport.
105

How to create interaction moments at concerts : Designing user experiences

Möller, Rebecka January 2018 (has links)
The concert industry has been expanded enormously the last couple of years. At the same time as the increasing engagement for concerts, the digital market is growing rapidly. Today during concerts, people use their smartphones to send text messages, connect on social media, take photos, record film clips, and use the flashlight function in a replacement of a lighter. This behaviour may be perceived as a distracting moment and instead moves the person’s focus from the live performance to the phone. The distracting moment can be solved by making an application that makes the interaction more enjoyable through the study of user experience. This can lead to more focus on the music and therefore, enhance the concert experience. In this project, the work behind the development of designing prototypes is described. The method used in the thesis is the process of Design Thinking. The process is divided into a five-step model: empathize, define, ideate, prototype and test. The result presents three prototypes that are based on digital competitions that interact the audience during a concert experience. At the end of the thesis, a discussion about how to secure a positive outcome of interacting the audience and the artist is presented. The conclusion was that the interactions have good potential to work in a concert environment, but the interactions need to be additionally tested to secure a positive outcome. Another conclusion was that the time before a concert has more scope to make interactions work well and to not distract the users from the live performance. / Konsertindustrin har expanderat enormt de senaste åren. Samtidigt som det ökande engagemanget för konserter, växer den digitala marknaden snabbt. Idag använder publiken sina mobiltelefoner under en konsert för att skicka textmeddelanden, ansluta på sociala medier, ta foton, spela in filmklipp och använda ficklampans funktion som en tändare. Det här beteendet kan uppfattas som ett distraherande ögonblick och i stället flytta personens fokus från konserten till telefonen. Det distraherande ögonblicket kan undvikas genom en studie av användarupplevelse som gör att en mobilapplikation gör samspelet smidigare. Det kan leda till mer fokus på musiken och genom det förbättra konsertupplevelsen. I det här projektet beskrivs arbetet bakom utvecklingen av prototyper. Metoden som används i rapporten är processen Design Thinking. Processen är uppdelad i en femstegsmodell: sympatisera, definiera, föreställa, prototyp och testa. Resultatet presenterar tre prototyper som bygger på digitala tävlingar som interagerar publiken under en konsertupplevelse. I slutet av rapporten presenteras en diskussion om hur man kan få ett positivt resultat av att interagera publiken och artisten med varandra. Slutsatsen var att interaktionerna har god potential att fungera i en konsertmiljö, men interaktionerna måste testas ytterligare för att säkerställa ett positivt resultat. En annan slutsats var att tiden före en konsert har mer spelrum för interaktionerna att fungera bra och att inte distrahera användarna från konsertupplevelsen.
106

The use and effectiveness of system development methodologies during the development of community based systems in South Africa / Ntombovuyo Wayi

Wayi, Ntombovuyo January 2014 (has links)
For the past few decades researchers, development agencies and government have focussed on the use of Information and Communication Technologies to improve the socio-economic status of people in underdeveloped rural communities. In recent years there has been remarkable recognition of the importance of developing systems that address the specific needs of rural communities. Education, health, commerce, government and agriculture are amongst the needs of rural communities that could well be addressed by these systems. System development is a complex process and studies have shown that if poorly conducted, the process could lead to the failure of the system being developed. Due to differences in context and application, the processes followed in the development of the rural community systems need to differ from those of commercial applications. One such difference is the choice of the Information System Development Methodology (SDM) used. Following a methodical approach to Information Systems development is important as it improves discipline, standardization and monitoring of a quality system. There are hundreds of SDM available for use during development and choosing the wrong SDM has been linked to problems such as systems being delivered late, being over budget or not meeting the needs of the users. Developing systems for disadvantaged communities is different from developing system for organisations or even affluent communities. Some of the challenges that developers encounter include lack of structure, poor computer literacy, and poor infrastructure. Lack of user involvement during system development has been linked to system failures. A Living Labs approach to socio-economic development is aimed at involving multiple stakeholders towards improving the living standards. Developing Community Information Systems aimed at solving varying community problems is one of the objectives of the Living Labs. There are only few CISs that are fully operational from South African Living Labs, and a number of systems developed are not in use. Poor user involvement and lack of use of system development are some of the reasons for system failures. The purpose of this study is to evaluate the use and effectiveness of System Development Methodologies when developing community information systems aimed at socio-economic development of disadvantaged communities. To achieve the objectives of this study, an interpretive, multiple case study research was conducted in three Living Labs around South Africa. To improve the chances for success during the development of Community Information Systems for use by disadvantage communities, this study proposes a framework for evaluating use and effectiveness of SDMs. The second output of the Study is an SDM framework that could be adopted specifically for Living Labs which adopts an agile approach and prototyping. These frameworks takes into account the social attributes of people in disadvantaged communities, the nature of the living lab, the nature of the systems being developed and the role of the users in the systems being developed. / PhD (Computer Science), North-West University, Potchefstroom Campus, 2014
107

The use and effectiveness of system development methodologies during the development of community based systems in South Africa / Ntombovuyo Wayi

Wayi, Ntombovuyo January 2014 (has links)
For the past few decades researchers, development agencies and government have focussed on the use of Information and Communication Technologies to improve the socio-economic status of people in underdeveloped rural communities. In recent years there has been remarkable recognition of the importance of developing systems that address the specific needs of rural communities. Education, health, commerce, government and agriculture are amongst the needs of rural communities that could well be addressed by these systems. System development is a complex process and studies have shown that if poorly conducted, the process could lead to the failure of the system being developed. Due to differences in context and application, the processes followed in the development of the rural community systems need to differ from those of commercial applications. One such difference is the choice of the Information System Development Methodology (SDM) used. Following a methodical approach to Information Systems development is important as it improves discipline, standardization and monitoring of a quality system. There are hundreds of SDM available for use during development and choosing the wrong SDM has been linked to problems such as systems being delivered late, being over budget or not meeting the needs of the users. Developing systems for disadvantaged communities is different from developing system for organisations or even affluent communities. Some of the challenges that developers encounter include lack of structure, poor computer literacy, and poor infrastructure. Lack of user involvement during system development has been linked to system failures. A Living Labs approach to socio-economic development is aimed at involving multiple stakeholders towards improving the living standards. Developing Community Information Systems aimed at solving varying community problems is one of the objectives of the Living Labs. There are only few CISs that are fully operational from South African Living Labs, and a number of systems developed are not in use. Poor user involvement and lack of use of system development are some of the reasons for system failures. The purpose of this study is to evaluate the use and effectiveness of System Development Methodologies when developing community information systems aimed at socio-economic development of disadvantaged communities. To achieve the objectives of this study, an interpretive, multiple case study research was conducted in three Living Labs around South Africa. To improve the chances for success during the development of Community Information Systems for use by disadvantage communities, this study proposes a framework for evaluating use and effectiveness of SDMs. The second output of the Study is an SDM framework that could be adopted specifically for Living Labs which adopts an agile approach and prototyping. These frameworks takes into account the social attributes of people in disadvantaged communities, the nature of the living lab, the nature of the systems being developed and the role of the users in the systems being developed. / PhD (Computer Science), North-West University, Potchefstroom Campus, 2014
108

Techno-economic analysis of an off-grid micro-hydrokinetic river system for remote rural electrification

Koko, S.P., Kusakana, K., Vermaak, H.J. January 2013 (has links)
Published Article / This study investigates the use of off-grid micro-hydrokinetic river system as a cost-effective and sustainable electricity supply option for remote rural residents in close proximity to flowing water and not having access to grid electricity. This hydrokinetic technology is still in the development stage and there is a lack of application especially in rural areas with reasonable water resource. This study will present the economic and environmental benefits of the proposed system. A mathematical model is developed to simulate the system performance as submitted to different solicitations. A test prototype will also be used in order to validate the simulation results.
109

Utformning av en Bollutslungare : Produktutvecklingsprojekt av en bollutslungare för hundsporten Flyball / Development of a ball launcher : Product development project of a ball launcher for the dog sport Flybal

Johansson, Jimmy January 2016 (has links)
This report is a product development project of a ball launcher as requested by Sörmons HundklubbLKk. The project har been carried out as a thesis for the Bachelor of Science for the Innovation anddesign engineer program at Karlstad University.The client wished to begin training in a dog sport called Flyball. This sport can be likened to a relayrace where two teams of dogs race against each other. One dog per team runs along a path, leapingover obstacles, up to a ball launcher. When the dog jumps at the ball launcher to stop its momentumand turn back, a ball, launched about two feet, is to be caught by the dog. The dog then returns thesame way along the track as it came to switch with the next dog on the team. The last dog who finishfirst wins for their team.Due to large costs when importing a ball launcher, and the product not being available in Sweden,the client wanted a Swedish version developed. The goal was to minimize the price with the criterionto maximize longevity.The work of the project has followed the product development process as studied at KarlstadUniversity, with great influence by idea generation techniques, analog and digital sketching, 3Dmodeling and mechanical drawing techniques. Construction of the prototype has been carried out inthe workshop at Karlstad University with an evolutionistic design approach. A combination of lateralthinking for creativity and vertical thinking for logic and confirmation was used throughout theproject.The result of the project was a prototype that could be tested in a real environment at the dog cluband was confirmed to function as desired. Due to the availability of material at the workshop,construction of the ball launcher was possible at no cost to the client. This was a request, althoughnot a requirement for the project.The client also wanted to keep the prototype which was constructed to use within the club fortraining purposes. Therefore the ball launcher was completed to a finished prototype after projectclosure. / Denna rapport behandlar ett produktutvecklingsprojekt av en bollutslungare på uppdrag av SörmonsHundklubb LKk. Projektet utfördes som ett examensarbete för högskoleingenjörsprogrammet iinnovationsteknik och design på Karlstads universitet.Uppdragsgivaren önskade börja med en hundsport som heter Flyball. Sporten kan liknas vid stafettdär två lag med hundar tävlar mot varandra. En hund per lag springer längst en bana över någrahinder fram till en bollutslungare. När hunden hoppar på bollutslungarens framsida för att vändakastas en boll ut en dryg halvmeter för att fångas av hunden. Hunden återvänder då längst banan föratt byta av med nästa hund i laget. Sista hund först i mål vinner för sitt lag.Då bollutslungaren var dyr att importera och inte fanns tillgänglig i Sverige önskade uppdragsgivarenatt en svensk version skulle utvecklas. Målsättningen var att minimera pris med kriteriet attmaximera livslängd.Arbetet följde produktutvecklingsprocessen såsom den studerats på Karlstads universitet med storinflytelse av idégenerering, analog och digital skissteknik, 3D-modellering och ritningsskapande.Konstruktion av funktionsmodell utfördes på verkstaden på Karlstads universitet med evolutionistiskutveckling av designen. En kombination av lateralt tänkade för kreativitet och vertikalt tänkade förlogik och bekräftelser användes genom projektet.Resultatet av projektet utmynnade i en funktionsmodell som kunde testas i verklig miljö påhundklubben och bekräfta att konceptet fungerade enligt önskemål. På grund av tillgängligt materialkunde konstruktionen av funktionsmodellen utföras utan kostnad för uppdragsgivaren vilket var ettönskemål, dock inte ett krav, för projektet.Uppdragsgivaren önskade behålla funktionsmodellen som skapades för att använda inom klubben förträning av Flyball. Därmed färdigställdes funktionsmodellen till funktionsredo efter projektets slutoch levererades till uppdragsgivaren.
110

Asynchronous time difference of arrival positioning system and implementation

He, Shuai 20 July 2016 (has links)
In this thesis, a complete localization system using asynchronous time difference of arrival (A-TDOA) technique has been thoroughly studied from concept to implementation. The work spans from a proposal of a new A-TDOA system deployment and modeling, through a derivation of the achievable estimation bound, to estimation algorithms development, to a hardware realization, and ultimately to measurements conducted in realistic radio environments. The research begins with a new deployment of an A-TDOA localization system. Compared to the conventional time of arrival (TOA) and time difference of arrival (TDOA) systems, it does not require clock synchronization within the network, which enables a flexible and fast deployment. When deployed in the simplest form, it can effectively reduce system complexity and cost, whereas if all anchor nodes are equipped with full transmit and receive capability, the A-TDOA system can achieve superior performance using a novel receiver re-selection technique. Determining the physical position of a target node in a noisy environment is critical. In this thesis, two novel algorithms, namely, a two-step and a constrained least squares (CLS) algorithms, are proposed offering excellent accuracy and the best trade-off between complexity and precision respectively. The two-step algorithm exploits the advantages of the semi-definite programming (SDP) and the Taylor method, i.e., global convergence and high precision, to achieve superior performance. The CLS algorithm significantly reduces the computation complexity while achieving good accuracy. Despite extensive research efforts on ranging and localization modeling and simulation, knowledge about practical implementations is limited. For the first time, a complete prototype based on A-TDOA technique is implemented in hardware. All sub-systems are developed from scratch and undergone significant modifications for improved reliability. The design objective is low cost and low complexity, and therefore a non-coherent receiver architecture was adopted. The target node design is based on receive and re-transmit technique and is prototyped in analog domain to avoid clock offset and skews. The implemented system has been extensively tested in an outdoor and indoor radio environments. The accuracy obtained are 20.7 cm and 15.2 cm respectively. Comparison with the literature published up to date proves the excellent quality of the design and implementation. To better understand the localization accuracy, the error sources due to thermal noise, hardware limitation, radio propagation channel and clock jitter are identified and investigated. Mitigation methods are proposed to reduce errors. / Graduate

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