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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.
61

An assessment of the state of e-government in South Africa - the case of the Government Employees Pension Fund

Fisher, Hilton 19 June 2006 (has links)
E-government, electronic Public Administration, has led to streamlined work processes within and between government departments. As theories of administration and management seek to improve processes, electronic administration seeks to improve electronic processes in an effort to provide efficient services. The unique contribution of this study on Public Administration and the related e-government initiatives of the Government Employees Pension Fund is that none of this research has been documented before. Whilst e-government is not new, its application to the Government Employees Pension Fund is novel. E-government espouses integrated partnerships between governments and e-citizens by creating an understanding of electronic relationships between and within organisations. The thesis considers electronic Public Administrative service delivery in the Government Employees Pension Fund as it relates to civil pensions administration. Successful e-government needs a critical mass of users that is central to ensuring its sustainable and successful utilisation. If a critical mass of users is not ensured then e-government initiatives will not be successful. Attempts by the Government Employees Pension Fund to develop a customer relationship management approach are assessed. Sustainable and successful e-service delivery is about providing multi-nodal access to clients. An interactive web site, amongst others, will allow clients to access services remotely. Seamless government is developed around customers’ needs and is outward looking since it provides a single access point for all services offered by government. Gaining access to information and communications technologies is a challenge that many face, hence the digital divide is a stymieing factor in providing seamless, successful e-government services. Not all e-government initiatives are successful. Information and communications technology initiatives are not always implemented according to planned timelines and budgets. The case of the Government Employees Pension Fund proved to be no different given that not all the e-government initiatives embarked upon were successful. / Thesis (PhD (Public Affairs))--University of Pretoria, 2007. / School of Public Management and Administration (SPMA) / unrestricted
62

Seamless speaker recognition

Chatzaras, Anargyros, Savvidis, Georgios January 2015 (has links)
In a technologically advanced society, the average person manages dozens of accounts for e-mail, social networks, e-banking, and other electronic services. As the number of these accounts increases, the need for automatic user identification becomes more essential. Biometrics have long been used to identify people and are the most common (if not the only) method to achieve this task. Over the past few years, smartphones have become frequently used gadgets.  These devices have built-in microphones and are commonly used by a single user or a small set of users, such as a couple or a family. This thesis uses a smartphone’s microphone to capture user’s speech and identify him/her. Existing speaker recognition systems typically prompt the user to provide long voice samples in order to provide accurate results. This results in a poor user experience and discourages users who do not have the patience to go through such a process.  The main idea behind the speaker recognition approach presented in this thesis is to provide a seamless user experience where the recording of the user’s voice takes place in the background. An Android application is developed which silently collects voices samples and performs speaker recognition without requiring extensive user interaction.  Two variants of the proposed tool have been developed and are described in depth in this thesis. The open source framework Recognito is used to perform the speaker recognition task. The analysis of Recognito showed that it is not capable of achieving high accuracy especially when the voice samples contain background noise. Finally, the comparison between the two architectures showed that they do not differ significantly in terms of performance. / I ett teknologiskt avancerat samhälle så hanterar den genomsnittliga personen dussintals konton för e-post, sociala nätverk, internetbanker, och andra elektroniska tjänster. Allt eftersom antalet konton ökar, blir behovet av automatisk identifiering av användaren mer väsentlig. Biometri har länge använts för att identifiera personer och är den vanligaste (om inte den enda) metoden för att utföra denna uppgift. Smartphones har under de senaste åren blivit allt mer vanligt förekommande, de ger användaren tillgång till de flesta av sina konton och, i viss mån, även personifiering av enheterna baserat på deras profiler på sociala nätverk. Dessa enheter har inbyggda mikrofoner och används ofta av en enskild användare eller en liten grupp av användare, till exempel ett par eller en familj. Denna avhandling använder mikrofonen i en smartphone för att spela in användarens tal och identifiera honom/henne. Befintliga lösningar för talarigenkänning ber vanligtvis användaren om att ge långa röstprover för att kunna ge korrekta resultat.  Detta resulterar i en dålig användarupplevelse och avskräcker användare som inte har tålamod att gå igenom en sådan process. Huvudtanken bakom den strategi för talarigenkänningen som presenteras i denna avhandling är att ge en sömlös användarupplevelse där inspelningen av användarens röst sker i bakgrunden. En Android-applikation har utvecklats som, utan att märkas, samlar in röstprover och utför talarigenkänning på dessa utan att kräva omfattande interaktion av användaren. Två varianter av verktyget har utvecklats och dessa beskrivs ingående i denna avhandling. Öpen source-ramverket Recognito används för att utföra talarigenkänningen. Analysen av Recognito visade att det inte klarar av att uppnå tillräckligt hög noggrannhet, speciellt när röstproverna innehåller bakgrundsbrus. Dessutom visade jämförelsen mellan de två arkitekturerna att de inte skiljer sig nämnvärt i fråga om prestanda.
63

Energy-efficient enhancements for IEEE 802.11 WLANs : On the way to enable Cellular/Wi-Fi networks interworking

Valdenebro González, Fernando January 2014 (has links)
Globally, the number of mobile broadband subscriptions is growing and the amount of mobile data traffic is expected to continue to grow rapidly. In the next five years the number of smartphone subscriptions is expected to more than double, while the amount of mobile traffic per active subscription per month of these subscribers is expected to nearly quadruple. As a consequence, mobile network operators (MNOs) aim to increase radio network capacity and coverage through heterogeneous deployments. In such heterogeneous networks, wireless local area networks (WLANs) are integrated with wireless wide area networks (WWANs), and there exist a tight interaction between them. The almost-ubiquitous support for IEEE802.11 WLANs (usually referred to as Wi-Fi®) makes this radio access technology a potential integrated component of near-future mobile broadband. With Wi-Fi completely integrated into mobile access, MNOs would optimize user experience and use of resources by controlling device’s choice of connectivity. In addition to guaranteeing the best user experience, optimal use of access networks should care about energy-efficiency in order to extend device’s battery life. However, the performance of Wi-Fi is far from meet neither energy-efficiency nor quality of service (QoS) user’s requirements. This radio access technology employs an energy-consuming medium access control (MAC) protocol that wastes both bandwidth and device’s energy resources. Therefore, enhanced MAC protocols, cleverly combined with standardized power saving mechanisms such as automatic power save delivery (APSD), would improve both energy-efficiency and QoS in order to enhance WLANs performance and meet user’s expectations. In addition, current WLAN discovery mechanisms neither meet requirements of the integrated scenario. Handover operations must be improved in terms of energy efficiency and latency. Consequently, enhanced handover schemes should reduce overall device’s energy consumption during the process, and enable seamless handover between Wi-Fi APs and between cellular/Wi-Fi networks. During this thesis project, the main challenges of Wi-Fi towards its integration into mobile access broadband have been analyzed. Consequently, a solution has been designed in order to address the identified challenges, which have been introduced in the previous paragraphs. The solution consists of enhancements for IEEE 802.11 WLANs based on current standards that achieve energy-efficiency and QoS, and facilitate Wi-Fi/cellular networks interworking. Finally, a custom-designed simulator has been used to evaluate the proposed solution. / Globalt sett är antalet mobila bredbandsabonnemang ökar och mängden av mobil datatrafik förväntas fortsätta att växa snabbt. Under de kommande fem åren kommer antalet smartphone-abonnemang väntas mer än fördubblas, medan mängden av mobiltrafiken per aktiv prenumeration per månad för dessa abonnenter väntas nästan fyrdubbla. Som en följd av mobiloperatörer som mål att öka sin radio nätkapacitet och täckning genom heterogena distributioner. I sådana heterogena nätverk, är trådlösa lokala nätverk (WLAN) integrerad med trådlösa WAN-nätverk (WWAN), och det finns en tät interaktion mellan dem. För att möta denna efterfrågan ämnar operatörer av mobila nätverk att öka kapacitet och täckning genom att bygga ut heterogena nätverk. I sådana heterogena nätverk integreras trådlösa lokala nätverk (WLAN) med nätverk med större yttäckning (cellulära nät) med täta interaktioner mellan de olika näten. Det mycket utbredda stödet för IEEE 802.11-standarden (ofta kallad för Wi-Fi®) för WLAN gör denna radioaccessteknik till en potentiell integrerad komponent för mobilt bredband i den nära framtiden. Med Wi-Fi som en integrerad i det mobila accessnätet kan mobilnätsoperatörer optimera användarupplevelsen och resursanvädningen genom att styra de mobila enheternas val av uppkoppling. Förutom att garantera den bästa användarupplevelsen så bör valet av accessnät ta hänsyn till energieffektiviteten för att förlänga batteridrifttiden för den mobila enheten. Wi-Fi är dock långt ifrån att uppfylla användarnas krav på energieffektivitet och tjänstekvalitet, eftersom denna radioaccessteknik använder ett mediumaccessprotokoll (MAC) som varken använder bandbredd eller batterienergi effektivt. Därför kan förbättrade MAC-protokoll kombinerade med standardiserade energibesparingslösningar såsom automatic power save delivery (APSD) ge bättre energieffektivitet och tjänstekvalitet, och därmed förbättra WLANs möjligheter att möta användarnas förväntningar. Dessutom har nuvarande nätverksidentifieringsmekanismer i WLAN svårt att uppfylla kraven i ett scenario med integrerade nätverk, eftersom den nuvarande sökmetoden är långsam och använder mycket energi. En förbättrad lösning bör minska energikonsumtionen under hela processen, och möjliggöra avbrottsfri övergång mellan Wi-Fi accessnoder och mellan cellulära och Wi-Fi-nätverk. Under detta examensarbete har de största utmaningarna för Wi-Fi under integrationen med mobil bredbandsaccess analyserats. En lösning har utvecklats för att lösa de identifierade problemen som beskrivits ovan. Lösningen består av förbättringar av IEEE 802.11 accessnät, som bygger vidare på existerande standardens energieffektivitets- och tjänstekvalitetslösningar och underlättar samverkan mellan Wi-Fi och cellulära nätverk. Slutligen har en egenutvecklad simulator använts för att utvärdera den föreslagna lösningen.
64

Data driven support of production through increased control of information parameters : A case study

Cavallin, Petter January 2020 (has links)
The current manufacturing business environment becomes more dependent of digital tools to increase business opportunities and customer value. The organizations ability to embrace the digital tools is dependent of a its digital maturity position. The organization structure, information systems, and communication are variables affecting the position and enables or disables possibility of data-based decisions-making (DBDM). To determine the ability information system and information flow is analyzed through a case study at one of the production departments. The areas studied in the case study are information flow of metal powder and compression tools.  The case study is performed to study the organizations ability to connecting information, study information flow and assess potential information disruption. It is assessed by using digital maturity assessments. This result provides an insight of how it affects the DBDM abilities within the department. These areas are common in a general production setting. The metal powder area is analyzed by an experiment where the metal powder containers is manually measured and evaluate the real weight compared to the depreciated weight in the information system. The compression tool analysis is performed by extracting and analyzing structured- and unstructured machine data from the production. This analytical angle is dependent of reliable data, and information disruption between the production processes and the servers is noticed during the extraction of data. This extraction process and analysis resembles the need when implementing machine learning and other automatic applications.  The 360DMA assess a general view of the organizations position and follow up with a method how to reach certain goals to increase one of the five levels. The Acatech-model is used to assess two structural areas, resources and information systems. The metal powder container analysis shows that there is a problem between the information stored in the systems regarding weight of the metal powder containers. The compression tool analysis result is that the stored data about the compression tools and the count of the different components is not correct. This and difficulties with manually- and automatically extracting data from server’s cause information disruptions and decrease the production process information reliability and validity. This decrease the ability to use the production data to make data driven decisions and gain insights about the production. The digital maturity assessment position the organization on a connectivity level (Acatech model) regarding information systems and resources means that data is unreliable and once its reliable the next level is in reach. The varying position within the 360DMA model call for management to synchronize development between processes by introducing strategies, define responsibilities and understand the information flow.
65

GPU-Accelerated Monte Carlo Geometry Processing for Gradient-Domain Methods

Mossberg, Linus January 2021 (has links)
This thesis extends the utility of the Monte Carlo approach to PDE-based methods presented in the paper Monte Carlo Geometry Processing. In particular, we implement this method on the GPU using CUDA, and investigate more viable methods of estimating the source integral when solving Poisson’s equation with intricate source terms. This is the case for a large group of gradient-domain methods in computer graphics, where source terms are represented by discrete volumetric data on regular grids. We develop unbiased source integral estimators like image-based importance sampling (IBIS) and biased estimators like source integral caching (SIC) and evaluate these against existing GPU-accelerated finite difference solvers for gradient-domain applications. By decoupling the source integration step from the WoS-algorithm, we find that the SIC method can improve performance by several orders of magnitude, making it competitive with existing finite difference solvers in many cases. We further investigate the viability of distance fields for accelerated distance queries and find that these can provide significant performance improvements compared to BVHs without meaningfully affecting bias. / <p>Examensarbetet är utfört vid Institutionen för teknik och naturvetenskap (ITN) vid Tekniska fakulteten, Linköpings universitet</p>
66

Mobilen som verktyg under användarens beslutsprocess

Olsson, Sara, Nordström, Agnes January 2023 (has links)
Detta examensarbete undersöker användningen av mobiltelefoner som verktyg under användares beslutsprocess i en omnichannel-kundresa med fysisk och virtuell interaktion. Syftet är att identifiera både möjligheter och problem som kan uppstå vid användning av mobilen i en sådan interaktion, med fokus på fenomenet Webrooming. Studien belyser vikten av interaktionsdesign och tjänstedesign för att skapa en sömlös och positiv kundupplevelse i omnichannel-detaljhandeln. Examensarbetet undersöker tidigare forskning inom området, analyserar befintliga exempel på omnichannel-strategier samt undersöker användares beslutsprocess med mobilen som verktyg. Studien tar insikter från Cultural Probes som metod där användare dokumenterar en Webrooming-resa med olika medel där mobilen är i fokus. Intervjuer genomförs för att komplettera eventuella kunskapsluckor och öka förståelsen för deltagarnas inlämnade kit. Vidare analyseras insamlade data via Affinitetsdiagram samt Customer Journey Maps. Genom att tillhandahålla en djupgående analys av den nuvarande situationen inom användarens beslutsprocess, kan detta examensarbete bidra till en ökad förståelse för hur användaren använder mobilen som verktyg under den fysiska och virtuella interaktionen med ett företags olika tjänster under en webrooming-resa. Studiens resultat visar att mobilen används genomgående under hela kundresan för beslutsfattande, informationssökande, jämförelser och rekommendationer. Den slutsats som dras från studien är att mobilen används för beslutsfattande på ett flertal punkter och är ett viktigt verktyg under användarens beslutsprocess. Trots vissa utmaningar med mobiltelefonen som verktyg, såsom små skärmar och problem med mobilwebbsidor, upplevs mobiltelefonen som ett lättillgängligt och smidigt verktyg. / This thesis examines the use of mobile phones as tools during users' decision-making process in an omnichannel customer journey with physical and virtual interactions. The purpose is to identify both opportunities and issues that may arise when using the mobile phone in such interactions, with a focus on the phenomenon of webrooming. The study highlights the importance of interaction design and service design in creating a seamless and positive customer experience in omnichannel retail. To achieve this, the thesis examines previous research in the field, analyzes existing examples of omnichannel strategies, and investigates users' decision-making process using the mobile phone as a tool. The study employs insights from Cultural Probes as a method, where users document a webrooming journey using various means with the mobile phone at the center. Interviews are conducted to fill any knowledge gap and increase understanding of participants' submitted kits. Furthermore, collected data is analyzed through Affinity Diagrams and Customer Journey Maps. By providing an in-depth analysis of the current situation within the user's decision-making process, this thesis can contribute to a better understanding of how users use the mobile phone as a tool during the physical and virtual interaction with a company's various services during a webrooming journey. The findings of the study show that the mobile phone is consistently used throughout the entire customer journey for decision-making, information-seeking, comparisons, and recommendations. The conclusion drawn from the study is that the mobile phone is used for decision-making at multiple points and is an important tool during a user's decision-making process. Despite certain challenges with the mobile phone as a tool, such as small screens and issues with mobile web pages, the mobile phone is perceived as an accessible and convenient tool.
67

Night Vision Goggle Simulation in a Mixed Reality Flight Simulator with Seamless Integrated Real World

Sproge, Sofia January 2024 (has links)
Night vision goggles (NVGs) are optical devices used to enhance human vision at low light conditions such as nighttime. The image seen through the goggles is brightened but with the consequence of introduced visual limitations and illusions. Because of this, fighter pilots need to undergo proper training with such equipment before operating with them in real-life. An NVG simulation within a Mixed Reality (MR) flight simulator can in theory be used to build the skills needed and directly translate them into real life. In this thesis, an NVG effect was added to a video see-through camera feed(VST) such that a whole NVG simulation could be experienced in an MR flight simulator. Furthermore, a method to seamlessly integrate the VST into the nocturnal virtual world was proposed. By conducting a semi structured interview with an NVG expert, the experienced realism, presence, and training value of the implemented effects were measured. A thematic analysis of the gathered interview data provided insight into the most important themes regarding NVG simulations within an MR flight simulator. / <p>Examensarbetet är utfört vid Institutionen för teknik och naturvetenskap (ITN) vid Tekniska fakulteten, Linköpings universitet</p>
68

Разработка и освоение технологии производства холоднодеформированных труб из сплава Ti-3Al-2,5V : магистерская диссертация / Development and application of production of cold-formed tubes technology from Ti-3Al-2.5V alloy

Рябов, И. С., Ryabov, I. S. January 2023 (has links)
Целью работы является разработка и освоение технологии производства холоднокатаной бесшовной трубной заготовки типоразмера из титанового сплава методом холодной прокатки. Составлена общая технологическая схема процесса производства: рассчитаны число проходов, размеры труб по проходам, расходный коэффициент, производительность, назначены основные и вспомогательные операции, режимы данных операций. Проведены расчеты основных параметров процесса прокатки, необходимые для его дальнейшей реализации в производственных условиях: рассчитаны калибровки прокатного инструмента, рассчитаны энергосиловые параметры процесса прокатки. Описаны особенности новой технологии. Представлено описание основного деформирующего оборудования, проведены расчеты на прочность деталей стана холодной прокатки. Проведены различные испытания, в том числе контроль механических свойств, контроль микроструктуры. Результаты испытаний показали, что трубы соответствуют требованиям нормативной документации. / The objective of the work is to develop and implement the production technology of standard size cold-rolled seamless pipe billet made of titanium alloy by cold rolling method. The general technological scheme of the production process was drawn up, in addition to that the number of passes, pipe sizes by passes, consumption factor, productivity, main and auxiliary steps, modes of these operations were calculated. As the next step, the calculations of the rolling process main parameters necessary for its further implementation in production conditions were carried out; these include: calculation of rolling tool calibration, calculation of rolling process energy and force parameters (rolling force, rotational moment, rolling power). After that the new technology characteristics were described. This work presents a main deforming equipment description, and strength calculations of cold rolling mill parts have been also carried out. As part of the work, various tests were performed, including mechanical properties inspection, microstructure monitoring. The test results showed that the pipes produced as a result of the work meet the requirements of the reference documentation.
69

Research on system architecture for device and content independent applications including 3d imaging and virtual reality as content / Recherche sur système de l'architecture pour dispositif et contenu indépendant, applications, y compris 3D l'imagerie et la réalité virtuelle comme contenu

Sultana, Razia 30 September 2014 (has links)
Les réseaux traitant l’information, intègrent différentes technologies incluant une large gamme de dispositifs aux capacités et puissances très variées et capables de gérer une immense quantité d’informations sous forme de données d’une grande diversité de formats. La recherche sur l'imagerie 3D, la réalité virtuelle et autres techniques holographiques permettront d’offrir de nouvelles techniques d’interactions homme/machine (IHM), notamment pour les appareils mobiles. Cela enrichira encore la variété et la diversité de ces dispositifs. Beaucoup d'efforts ont été faits, notamment ces dernières années, afin d’établir une intégration ouverte, évolutive et transparente des différentes technologies permettant l’affichage de contenus, notamment d’images 2D et 3D et ce pour tout type de système, y compris mobile en tenant compte, notamment et de plus en plus, de la situation géographique individuelle de l'utilisateur final. Sur ces différents points, la tâche est loin d’être terminée. Cette thèse représente, dans ce contexte, une contribution, vers la généralisation de la transportabilité des informations pour des objets communicants de natures différentes, notamment portables, particulièrement dans le cas de l’imagerie en 3 dimensions, de plus en plus exploitée.L'objectif de ce travail de recherche est de trouver un moyen de résoudre le problème énoncé ci-dessus en proposant une architecture pour fournir un accès sans contrainte, continu et personnalisé pour le contenu et les applications interactives partout et à tout moment avec la plus grande quantité possible d’appareils communicants. Un exemple d’exploitation utile et particulièrement adaptée d'un tel système est l'apprentissage sur mobile en raison de la grande diversité des appareils communicants disponibles, dotés de caractéristiques et de fonctionnalités très différentes. Comme solution au problème considéré, une nouvelle architecture nommée "Smoothie" est proposée, un prototype a été développé et évalué en tant que composant important d'un jeu d'apprentissage collaboratif de langues étrangères nommé LLG (Language Learning Game). / Today’s network landscape consists of many different network technologies, a wide range of end-devices with large scale of capabilities and power, an immense quantity of information and data represented in different formats. Research on 3D imaging, virtual reality and holographic techniques will result in new user interfaces (UI) for mobile devices and will increase their diversity and variety. A lot of effort is being made in order to establish open, scalable and seamless integration of various technologies and content presentation for different devices including those that are mobile, considering the individual situation of the end user. Till today the research is going on in different parts of the world but the task is not completed yet.The goal of this research work was to find a way to solve the above stated problems by investigating system architectures to provide unconstrained, continuous and personalized access to the content and interactive applications everywhere and at anytime with different devices. As a Solution of the problem considered, a new architecture named “Smoothie” is proposed, developed as prototype and evaluated as an important feature of a collaborative foreign language learning game named LLG.
70

Analýza a inovace elektrických motorků pro automobily / Automotive Electric Motors Analysis and Innovation

Špaček, Ladislav January 2011 (has links)
Direct current motors and stepping motors are very often used for electric drives in cars. The most frequent representatives of direct current motors are electric starter and wind- screen wiper motor. Stepping motors are very often used for electric regulating of outsides driving mirrors and seats. This study is focused on innovation and DC permanent magnet motor. The disadvanage of direct current motors is so called „sliding contact“. A possible compensation of direct current motor are EC (electronically commutator) motors that do not need sliding contact for their work.

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