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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.
801

Designing a dynamic thermal and energy system simulation scheme for cross industry applications / W. Bouwer

Bouwer, Werner January 2004 (has links)
The South African economy, which is largely based on heavy industry such as minerals extraction and processing, is by nature very energy intensive. Based on the abundance of coal resources, electricity in South Africa remains amongst the cheapest in the world. Whilst the low electricity price has contributed towards a competitive position, it has also meant that our existing electricity supply is often taken for granted. The economic and environmental benefits of energy efficiency have been well documented. Worldwide, nations are beginning to face up to the challenge of sustainable energy - in other words to alter the way that energy is utilised so that social, environmental and economic aims of sustainable development are supported. South Africa as a developing nation recognises the need for energy efficiency, as it is the most cost effective way of meeting the demands of sustainable development. South Africa, with its unique economic, environmental and social challenges, stands to benefit the most from implementing energy efficiency practices. The Energy Efficiency Strategy for South Africa takes its mandate from the South African White Paper on Energy Policy. It is the first consolidated governmental effort geared towards energy efficiency practices throughout South Africa. The strategy allows for the immediate implementation of low-cost and no-cost interventions, as well as those higher-cost measures with short payback periods. An initial target has been set for an across sector energy efficiency improvement of 12% by 2014. Thermal and energy system simulation is globally recognised as one of the most effective and powerful tools to improve overall energy efficiency. However, because of the usual extreme mathematical nature of most simulation algorithms, coupled with the historically academic environment in which most simulation software is developed, valid perceptions exist that system simulation is too time consuming and cumbersome. It is also commonly known that system simulation is only effective in the hands of highly skilled operators, which are specialists in their prospective fields. Through previous work done in the field, and the design of a dynamic thermal and energy system simulation scheme for cross industry applications, it was shown that system simulation has evolved to such an extent that these perceptions are not valid any more. The South African mining and commercial building industries are two of the major consumers of electricity within South Africa. By improving energy efficiency practices within the building and mining industry, large savings can be realised. An extensive investigation of the literature showed that no general suitable computer simulation software for cross industry mining and building thermal and energy system simulation could be found. Because the heating, ventilation and air conditioning (HVAC) of buildings, closely relate to the ventilation and cooling systems of mines, valuable knowledge from this field was used to identify the requirements and specifications for the design of a new single cross industry dynamic integrated thermal and energy system simulation tool. VISUALQEC was designed and implemented to comply with the needs and requirements identified. A new explicit system component model and explicit system simulation engine, combined with a new improved simulation of mass flow through a system procedure, suggested a marked improvement on overall simulation stability, efficiency and speed. The commercial usability of the new simulation tool was verified for building applications by doing an extensive building energy savings audit. The new simulation tool was further verified by simulating the ventilation and cooling (VC) and underground pumping system of a typical South African gold mine. Initial results proved satisfactory but, more case studies to further verify the accuracy of the implemented cross industry thermal and energy system simulation tool are needed. Because of the stable nature of the new VISUALQEC simulation engine, the power of the simulation process can be further extended to the mathematical optimisation of various system variables. In conclusion, this study highlighted the need for new simulation procedures and system designs for the successful implementation and creation of a single dynamic thermal and energy system simulation tool for cross industry applications. South Africa should take full advantage of the power of thermal and energy system simulation towards creating a more energy efficient society. / Thesis (Ph.D. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2005.
802

Context-aware information systems and their application to health care

Kawasme, Luay 14 October 2008 (has links)
This thesis explores the field of context-aware information systems (CAIS). We present an approach called Compose, Learn, and Discover (CLD) to incorporate CAIS into the user daily workflow. The CLD approach is self-adjusting. It enables users to personalise the information views for different situations. The CAIS learns about the usage of the information views and recalls the right view in the right situation. We illustrate the CLD approach through an application in the health care field using the Clinical Document Architecture (CDA). In order to realise the CLD approach, we introduce Semantic Composition as a new paradigm to personalise information views. Semantic Composition leverages the type information in the domain model to simplify the user-interface composition process. We also introduce a pattern discovery mechanism that leverages data-mining algorithms to discover correlations between user information needs and different situations.
803

Hydraulophones: Acoustic Musical Instruments and Expressive User Interfaces

Janzen, Ryan E. 03 January 2011 (has links)
Fluid flow creates an expansive range of acoustic possibilities, particularly in the case of water, which has unique turbulence and vortex shedding properties as compared with the air of ordinary wind instruments. Sound from water flow is explained with reference to a new class of musical instruments, hydraulophones, in which oscillation originates directly from matter in its liquid state. Several hydraulophones which were realized in practical form are described. A unique user-interface consisting of a row of water jets is presented, in terms of its expressiveness, tactility, responsiveness to derivatives and integrals of displacement, and in terms of the direct physical interaction between a user and the physical process of sound production. Signal processing algorithms are introduced, which extract further information from turbulent water flow, for industrial applications as well as musical applications.
804

Hydraulophones: Acoustic Musical Instruments and Expressive User Interfaces

Janzen, Ryan E. 03 January 2011 (has links)
Fluid flow creates an expansive range of acoustic possibilities, particularly in the case of water, which has unique turbulence and vortex shedding properties as compared with the air of ordinary wind instruments. Sound from water flow is explained with reference to a new class of musical instruments, hydraulophones, in which oscillation originates directly from matter in its liquid state. Several hydraulophones which were realized in practical form are described. A unique user-interface consisting of a row of water jets is presented, in terms of its expressiveness, tactility, responsiveness to derivatives and integrals of displacement, and in terms of the direct physical interaction between a user and the physical process of sound production. Signal processing algorithms are introduced, which extract further information from turbulent water flow, for industrial applications as well as musical applications.
805

An intuitive motion-based input model for mobile devices

Richards, Mark Andrew January 2006 (has links)
Traditional methods of input on mobile devices are cumbersome and difficult to use. Devices have become smaller, while their operating systems have become more complex, to the extent that they are approaching the level of functionality found on desktop computer operating systems. The buttons and toggle-sticks currently employed by mobile devices are a relatively poor replacement for the keyboard and mouse style user interfaces used on their desktop computer counterparts. For example, when looking at a screen image on a device, we should be able to move the device to the left to indicate we wish the image to be panned in the same direction. This research investigates a new input model based on the natural hand motions and reactions of users. The model developed by this work uses the generic embedded video cameras available on almost all current-generation mobile devices to determine how the device is being moved and maps this movement to an appropriate action. Surveys using mobile devices were undertaken to determine both the appropriateness and efficacy of such a model as well as to collect the foundational data with which to build the model. Direct mappings between motions and inputs were achieved by analysing users' motions and reactions in response to different tasks. Upon the framework being completed, a proof of concept was created upon the Windows Mobile Platform. This proof of concept leverages both DirectShow and Direct3D to track objects in the video stream, maps these objects to a three-dimensional plane, and determines device movements from this data. This input model holds the promise of being a simpler and more intuitive method for users to interact with their mobile devices, and has the added advantage that no hardware additions or modifications are required the existing mobile devices.
806

Joker: um realizador de desenhos animados para linguagens formais

Souza, Diego Henrique Oliveira de 31 August 2011 (has links)
Made available in DSpace on 2014-12-17T15:47:56Z (GMT). No. of bitstreams: 1 DiegoHOS_DISSERT.pdf: 2899752 bytes, checksum: d3160b774efd6749eced9bb34d4a74cf (MD5) Previous issue date: 2011-08-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Using formal methods, the developer can increase software s trustiness and correctness. Furthermore, the developer can concentrate in the functional requirements of the software. However, there are many resistance in adopting this software development approach. The main reason is the scarcity of adequate, easy to use, and useful tools. Developers typically write code and test it. These tests usually consist of executing the program and checking its output against its requirements. This, however, is not always an exhaustive discipline. On the other side, using formal methods one might be able to investigate the system s properties further. Unfortunately, specification languages do not always have tools like animators or simulators, and sometimes there are no friendly Graphical User Interfaces. On the other hand, specification languages usually have a compiler which normally generates a Labeled Transition System (LTS). This work proposes an application that provides graphical animation for formal specifications using the LTS as input. The application initially supports the languages B, CSP, and Z. However, using a LTS in a specified XML format, it is possible to animate further languages. Additionally, the tool provides traces visualization, the choices the user did, in a graphical tree. The intention is to improve the comprehension of a specification by providing information about errors and animating it, as the developers do for programming languages, such as Java and C++. / Usando m?todos formais, o desenvolvedor pode aumentar a confiabilidade e corretude do software. Al?m disso, o desenvolvedor pode concentrar-se mais nos requisitos funcionais. Por?m h? muita resist?ncia em se adotar essa abordagem de desenvolvimento de software. A raz?o principal e a escassez de suporte ferramental adequado, ?til e de f?cil utiliza??o. Os desenvolvedores normalmente escrevem o c?digo e o testam. Estes testes geralmente consistem em checar se as sa?das est?o de acordo com os requisitos. Isto, contudo, nem sempre e poss?vel de maneira exaustiva. Por outro lado, usando M?todos Formais um desenvolvedor e capaz de investigar profundamente as propriedades do sistema. Infelizmente, linguagens de especifica??o formal nem sempre possuem ferramentas como animador ou simulador e ?s vezes n?o h? interfaces gr?ficas amig?veis. Por?m, algumas dessas ferramentas possuem um compilador, que gera um Sistema de Transi??es Rotuladas (LTS). A proposta deste trabalho ? desenvolver um aplicativo que fornece anima??o gr?fica para especifica??es formais usando o LTS como entrada. O aplicativo inicialmente suporta as as linguagens B, CSP e Z. Usando o LTS em um formato XML especificado ? poss?vel animar outras linguagens formais. Adicionalmente a ferramenta disponibiliza visualiza??o de traces, escolhas feitas pelo usu?rio, em um formato de ?rvore gr?fica. A inten??o ? melhorar a compreens?o de uma especifica??o, fornecendo informa??es sobre erros e animando-a, como os desenvolvedores fazem com linguagens de programa??o como Java e C++.
807

An accessible grocery store for low vision customers : Human-centered design of a universal shopping solution, with a focus on people with low vision

Pihl, Johan January 2018 (has links)
Around one percent of the Swedish population is defined as visually impaired and ten percent of them are classified as blind (Funka, n.d.; SRF, 2017a). A study shows that the prevalence of nearsightedness will increase to around half the population in the world in 2050 (Holden et. al., 2016). This suggests an increased need for solutions that work for people with reduced vision, not only for visually impaired but for a large group of the population. The aim of the project is to conceptualize a technological mainstream solution that supports people when shopping for groceries. The focus is on making this solution accessible for people with low vision. The project was planned based on the human-centered design process described by IDEO.org (2015), with an overall process divided into three phases: inspiration, ideation, and implementation. In the first phase, inspiration, a literature review was done, different field studies and other research methods were carried out. The outcome of the phase was three personas, two scenarios, and a design specification. During the second phase, ideation, the project scope was narrowed down – focusing on physical grocery stores (excluding online stores) and on conceptualizing a smartphone application. An ideation workshop was conducted, followed by concept creation, paper prototyping, scenario writing, user evaluations and a final concept selection. In the last phase, implementation, follow up feedback sessions were held and a simulation test of the final concept was held. Visualizations and presentation of the final concept were done. A list of summarized design principles was created, as support for further work on designing the application for low vision users. The final concept is based on a smartphone application that supports the customer through shopping list management, aisle navigation, item selection and item scanning, for a seamless customer experience for both people with full and low vision. The technology that will be utilized is Pricer AB's electronic shelf labels (ESL) with item positioning, customer navigation, and individual flashing light, combined with the grocery store online database with item descriptions and images. Here follows an example of how the interaction could look like for someone with low vision: He always prepares his shopping list before heading to the store, this way he knows the shopping will be easier for him. In the store, he gets all items on the list presented in the correct order of the store, in that way he knows what to search for. When looking for soy sauce from his shopping list he has trouble remembering where the section is, so he checks it up with the navigation. He realizes that it was just around the corner of where he just passed by. Once at the section he is presented with a list of different soy sauces in the application, matching his location, previous purchases and the soy sauce on his shopping list. He can now select the one that he prefers, and a picture of it appears on the screen, simultaneously a flashing green light appears by the item on the shelf, and he can easily and independently find the way right up to the soy sauce he wants. / Ungefär en procent av Sveriges befolkning är synskadade, och tio procent av dem är så pass gravt synskadade att de kan definieras som blinda (Funka, n.d.; SRF, 2017a). Enligt en studie förväntas närsynthet världen över att öka, och under 2050 vara uppe i hälften av jordens befolkning (Holden et. al., 2016). Detta tyder på ett ökat behov av lösningar som fungerar för personer med nedsatt syn, inte bara för synskadade utan för en stor del av befolkningen. Målet med projektet är att undersöka nuläget och behoven för synsvaga personer när de handlar mat, för att sedan kunna utveckla universell teknisk ­lösning som ska fungera som ett stöd när man handlar mat. Projektet planerades utifrån en människocentrerad designprocess beskriven av IDEO.org (2015), som är indelad i tre faser: inspiration, idégenereringen och genomförande. I den första fasen, inspiration, gjordes en litteraturstudie, flera fältstudier genomfördes, samt andra research metoder. Resultatet här var tre personas, två scenarion och en designspecifikation. Under den andra fasen, idégenereringen, ställdes nya avgränsningar upp för projektet – fokuset riktades nu mot den fysiska butiker (avgränsning från e-handeln) och att målet skulle vara att ta fram en smartphone-applikation. En idéworkshop genomfördes, konceptgenerering, skapande av pappersprototyper, scenarion, utvärdering med användare och ett slutligt konceptval. I sista fasen, genomförande, följdes det slutliga konceptet upp med tidigare deltagare och det slutliga konceptet testades i en simulerad studie. Visualisering och presentation av slutkonceptet gjordes. Designprinciper för utveckling av applikationer för synsvaga sammanfattades, för att fungera som stöd för vidare arbete med utveckling av konceptet. Slutkonceptet bygger på en smartphone-applikation som ska fungera som stöd för kunden, från skapandet av inköpslista, navigering i butiken, val och identifiering av varor och slutligen att scanna varan. I sin helhet skapar detta en komplett lösning i mataffären för både seende och synsvaga kunder. Tekniken som ska utnyttjas för konceptet är Pricer AB's elektroniska hyllkantsetikett-system (ESL-system) med positionering, kundnavigering samt en lysdiod på varje enskild etikett, i kombination med butikens online-databas med produktbeskrivningar och bilder på varorna. Här kommer en beskrivning av hur interaktionen med systemet kan gå till för någon som är synsvag: Han förbereder alltid sin inköpslista innan han går till affärer, eftersom han vet att det underlättar för honom. Väl i butiken får han varorna från inköpslistan presenterade i den ordningen de kommer, vilket förenklar letandeprocessen. När han letar efter sojasås som han har på listan har han svårt att komma ihåg var i butiken han hittar den, så han kollar upp det med navigeringsfunktionen. Han inser då att han missade den just bakom hörnet som han gick förbi. Väl framme vid sektionen får han en lista med olika sojasåser presenterade i applikationen, de baseras på hans position i butiken, tidigare köp och vad han har på inköpslistan. Han kan nu välja den han gillar och får då en bild på varan på sin skärm, samtidigt som en grön lampa blinkar precis där varan är placerad på hyllan. Han kan nu enkelt och självständigt plocka varan han vill ha från hyllan.
808

En jämförelse mellan native-, hybrid- och webbapplikationer : En undersökning om applikationernas prestandaskillnader i användargränssnittet. / A comparison between native, hybrid and web applications : A study of the applications performance differences in the user interface.

Dahlquist, Victoria January 2018 (has links)
Sammanfattning Syfte - Syftet med studien är att undersöka vilka parametrar som kan komma att påverka applikationens rendering av användargränssnittet samt hur den skiljer sig i webbapplikation, hybridapplikation och nativeapplikation. Denna undersökning har för avsikt att besvara följande frågeställningar: 1.         Vilka parametrar kan påverka rendering av användargränssnittet på en mobil applikation?   2.         Hur skiljer sig renderingen av användargränssnittet hos webbapplikation, hybridapplikation och nativeapplikation?   Metod - Studien använder sig av en litteraturstudie för att besvara första frågeställningen och en experimentell studie där en hypotes samt förutsägelse formuleras och testas för att besvara andra frågeställningen.   Resultat – Resultatet från studien visar att nativeapplikationen inte alltid ger bättre prestanda vid utförande av samma uppgifter gentemot motsvarande webb- och hybridapplikation. Webbapplikationen hade genomgående bäst prestanda i användargränssnittet, medan hybridapplikation ofta gav sämre prestanda än de motsvarande applikationstyperna.   Implikationer - Studien bidrar till att utvidga kunskapen inom native-, hybrid- och webbapplikationers prestanda i användargränssnittet och kan ge företag samt utvecklare referensdata att grunda deras val av applikationstyp på. Studien påvisar att alla applikationstyper är värda att överväga, men webb- och nativeapplikationen presterade något bättre.   Begränsningar - Inga långtidstester kunde jämföras eftersom ADB inte läser av grafiskdata för webbapplikationer och Chrome DevTools inte kan utföra långa tester. / Abstract Purpose – The purpose of this thesis is to examine which parameters may affect application rendering of the user interface and how it differs in web application, hybrid application and native application. This thesis intends to answer the following research questions: Which parameters can affect the rendering of the user interface on a mobile application?    How does the rendering of the user interface differ from web application, hybrid application and native application? Method – The study uses a literature study to answer the first research question and uses an experimental study in which a hypothesis and prediction are formulated and tested to answer the second research question.   Results – The result of the study shows that the performance of the native application’s user interface does not always perform better when performing the same task as the corresponding web and hybrid application. The web application in general had the best performance in the user interface, while hybrid application often performed inferior to the corresponding application types.   Implications – The study contributes to extend the knowledge of native application’s, hybrid application’s and web application’s performance in the user interface, and can give companies and developers reference data to base their decision on the choice of application type. The study shows that all application types are worth considering, but the web and native application performed slightly better.   Limitations – No long-term tests could be compared because ADB does not read graphical data for web applications and Chrome DevTools cannot perform long running tests.
809

Reuso de IHC orientado a padrões concretos de interação e dirigido por casos de uso / A concrete interaction pattern oriented and use case driven HCI reuse approach

Moreira, Augusto Abelin January 2007 (has links)
A prática de reuso, apesar de ser universalmente e reconhecidamente aceita como uma boa prática, ainda não atingiu um estágio de maturidade satisfatório nas instituições. Em particular, a definição e a construção das interfaces com o usuário (IHC) ainda carecem de abordagens efetivas e sistemáticas de reuso, mesmo se comparadas com as práticas já existentes de reuso dos demais artefatos de software. O objetivo deste trabalho é duplo: investigar abordagens de reuso de interfaces do usuário (IHC), analisando-as do ponto de vista da sua aplicabilidade, adequação e integração em um processo de desenvolvimento de software baseado na UML e propor uma abordagem de reuso de artefatos de software interativo dirigida por casos de uso, integrando – por meio de alguns aspectos do ciclo de vida de casos de uso (da modelagem à implementação) – vários conceitos e técnicas de reuso bem conhecidos como padrões de casos de uso, padrões de interação e padrões de projeto. O foco principal é a definição de como promover o reuso de interface com o usuário baseado em padrões e de como usar e implementar esses padrões através do reuso de código e/ou de componentes. / Reuse practicing, although universally and recognizably accepted as good practice, hasn’t reached a fair maturity level in organizations. Specifically, the definition and construction of user interfaces (HCI) lack effective and systematic reuse approaches even when compared with other reuse practices used nowadays. This work has a dual-purpose: to make a survey of reuse approaches of user interfaces (HCI) and their applicability in a development process based on UML, and to present a use case driven software reuse approach for interactive systems, integrating – by means of some aspects of use case life cycle (from modeling to implementation) - several well-known reuse concepts and techniques like use case patterns, interaction patterns and design patterns. The approach focuses on how to promote user interface reuse based on patterns and how to use and implement them through code reuse and/or component reuse.
810

Um modelo baseado em princípios de usabilidade para aplicação em interfaces de usuário para a interação humano-computador

Pechansky, Rubem January 2011 (has links)
A maturidade da área de Interação Humano-Computador (IHC) pode ser atestada pela grande quantidade de conjuntos formados por regras, diretrizes e normas (aqui designados como diretivas) que têm sido formulados por dezenas de autores como guias para o estudo, criação e melhoria de interfaces de usuário. No entanto, esses conjuntos apresentam diferenças significativas entre si: muitas dessas diretivas, incluindo algumas já consagradas no universo da IHC, não pertencem ao mesmo nível de abstração nem formam um conjunto homogêneo de enunciados. Essa falta de unidade, aliada à acelerada evolução das tecnologias digitais, tem contribuído para manter essas diretivas (e a própria disciplina de IHC, segundo alguns) em um estado constante de fragmentação e permanente modificação. Mesmo assim, podem ser encontrados princípios — ou leis essenciais, universais e imutáveis — que são subjacentes às diretivas e que podem delas ser extraídos através de uma metodologia adequada. Para contribuir com esse processo, a presente pesquisa apresenta uma revisão dos critérios utilizados para a compilação de conjuntos de diretivas de usabilidade, além de um método de três etapas para a redução progressiva de um número significativo de diretivas a uma lista simples de princípios de usabilidade. Os resultados deste trabalho incluem um modelo metodológico e um conjunto de sete princípios que podem ser utilizados para a pesquisa a e prática da Interação Humano-Computador. / The maturity of the Human-Computer Interaction (HCI) field can be attested by the large number of existing sets of rules, guidelines and standards (called directives herein) that have been formulated by dozens of authors as guidelines for the study, design and improvement of user interfaces. Still, these sets present significant differences among themselves: many of these directives, including some already established in the realm of HCI, do not belong to the same level of abstraction and do not constitute a homogeneous set of statements. This lack of unity, coupled with the rapid evolution of digital technologies, has contributed to maintain these directives (and, according to some, the very discipline of HCI) in a constant state of fragmentation and perpetual change. Even so, it is possible to find among them certain principles — i.e., essential laws that are universal and immutable — which underlie these directives and can be extracted from them using an appropriate methodology. To contribute to this process, this research presents a review of the criteria used to compile these sets of usability directives and a three-step method for the progressive reduction of a significant number of directives to a simple list of usability principles. The results include a methodological framework and seven principles that can be used for the research and practice of Human-Computer Interaction.

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