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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.
291

Designing An Information System For Material Management In Engineer-to-order Organizations

Dede, Erdogan 01 January 2007 (has links) (PDF)
In this thesis, an information system is designed and developed for engineer-to-order organizations to improve the traditional Bill-of-Material by handling variants of products and components efficiently. A database is developed to store the related information about inventories and configuration management in an effective way. The improved Bill-of-Material provides a common structure to access stored information for material management purposes. A model, based on network, is presented and included into the system for calculating time required to produce components and to make subassemblies or assemblies with the current inventory levels. The system is applied to T&Uuml / BiTAK-SAGE, which is an engineer-to-order organization carrying out Research and Development projects for Defense Industry.
292

Design of a New Suturing and Knot Tying Device for Laparoscopic Surgery

Onal, Sinan 31 August 2010 (has links)
Minimally invasive or laparoscopic surgery has completely changed the focus of surgery becoming an alternative to various types of open surgery. Minimally invasive surgery avoids invasive open surgery as the operation is performed through one or more small incisions in the abdomen and using a small camera called laparoscope. Through these incisions, surgeons insert specialized surgical instruments to perform the operation resulting in less postoperative pain, shorter hospital stay, and faster recovery. However, the main problems during minimally-invasive surgery are the limited space for operating instruments and the reduced visibility and range of motion inside the patient’s body. During minimally-invasive surgery, one of the most difficult and time consuming surgical procedures is suturing and knot tying. This procedure significantly increases the operation time as it requires advanced techniques and extensive experience by surgeons.The main goal of this research is to investigate, design, and develop a new suturing instrument to facilitate suturing procedures during minimally invasive surgery.Qualitative research data was collected through interviews with a surgeon and six indepth observations of minimally invasive surgeries at Tampa General Hospital. Different design concepts and mechanisms were created using SolidWorks CAD software, and tested using SimulationXpress in order to identify dimensions, materials and expected performance of the design and its components. The prototypes of the device were made using a Dimension SST 768 FDM machine and tested by the surgeon to ensure that the final design meets the specified needs and criteria. This new device will eliminate the use of many different devices during the operation and allow the use of any type of suture. The proposed suturing device aims to benefit both patients and surgeons. For surgeons, the new device aims to decrease the number of steps for laparoscopic suturing through an intuitive and ergonomic design. For patients, the proposed device will reduce time during surgery and under general anesthesia leading towards improved health care.
293

Capsule endoscopy system with novel imaging algorithms

2013 November 1900 (has links)
Wireless capsule endoscopy (WCE) is a state-of-the-art technology to receive images of human intestine for medical diagnostics. In WCE, the patient ingests a specially designed electronic capsule which has imaging and wireless transmission capabilities inside it. While the capsule travels through the gastrointestinal (GI) tract, it captures images and sends them wirelessly to an outside data logger unit. The data logger stores the image data and then they are transferred to a personal computer (PC) where the images are reconstructed and displayed for diagnosis. The key design challenge in WCE is to reduce the area and power consumption of the capsule while maintaining acceptable image reconstruction. In this research, the unique properties of WCE images are identified by analyzing hundreds of endoscopic images and video frames, and then these properties are used to develop novel and low complexity compression algorithms tailored for capsule endoscopy. The proposed image compressor consists of a new YEF color space converter, lossless prediction coder, customizable chrominance sub-sampler and an efficient Golomb-Rice encoder. The scheme has both lossy and lossless modes and is further customized to work with two lighting modes – conventional white light imaging (WLI) and emerging narrow band imaging (NBI). The average compression ratio achieved using the proposed lossy compression algorithm is 80.4% for WBI and 79.2% for NBI with high reconstruction quality index for both bands. Two surveys have been conducted which show that the reconstructed images have high acceptability among medical imaging doctors and gastroenterologists. The imaging algorithms have been realized in hardware description language (HDL) and their functionalities have been verified in field programmable gate array (FPGA) board. Later it was implemented in a 0.18 μm complementary metal oxide semiconductor (CMOS) technology and the chip was fabricated. Due to the low complexity of the core compressor, it consumes only 43 µW of power and 0.032 mm2 of area. The compressor is designed to work with commercial low-power image sensor that outputs image pixels in raster scan fashion, eliminating the need of significant input buffer memory. To demonstrate the advantage, a prototype of the complete WCE system including an FPGA based electronic capsule, a microcontroller based data logger unit and a Windows based image reconstruction software have been developed. The capsule contains the proposed low complexity image compressor and can generate both lossy and lossless compressed bit-stream. The capsule prototype also supports both white light imaging (WLI) and narrow band imaging (NBI) imaging modes and communicates with the data logger in full duplex fashion, which enables configuring the image size and imaging mode in real time during the examination. The developed data logger is portable and has a high data rate wireless connectivity including Bluetooth, graphical display for real time image viewing with state-of-the-art touch screen technology. The data are logged in micro SD cards and can be transferred to PC or Smartphone using card reader, USB interface, or Bluetooth wireless link. The workstation software can decompress and show the reconstructed images. The images can be navigated, marked, zoomed and can be played as video. Finally, ex-vivo testing of the WCE system has been done in pig's intestine to validate its performance.
294

Modélisation et Optimisation d'un Générateur Synchrone à Double Excitation de Forte Puissance

Ammar, Aymen 28 June 2013 (has links) (PDF)
Alliant flexibilité de contrôle et bon rendement, les Machines Synchrone à Double Excitation (MSDE) sont de plus en plus investiguées pour diverses applications de petites et moyennes puissances et rarement pour des applications de fortes puissances. Cette thèse a pour objectif l'étude d'un Générateur Synchrone à Double Excitation (GSDE) de forte puissance. Un modèle de comportement a été établi. Des méthodes analytiques et semi-analytiques ont été utilisées pour la modélisation multi-physique de la machine. Ce modèle a été validé, dans un premier temps, par comparaison aux résultats d'un modèle éléments finis.Comparé à un Générateur Synchrone à Pôles Saillants (GSPS), le GSDE offre des solutions plus intéressantes énergétiquement et économiquement, que ce soit en fonctionnement à vitesse constante ou à vitesse variable. Dans le cadre d'un fonctionnement en générateur éolien, l'augmentation du nombre d'encoche par pôle et par phase et l'augmentation de la fréquence d'alimentation contribuent à l'amélioration des performances de la GSDE. Cependant il faudrait tenir compte des impacts sur l'électronique de puissance et le multiplicateur mécanique. En plus, la distribution de Weibull et le bon choix de la plage utile de variation de la vitesse du vent, jouent un rôle important sur le dimensionnement optimal du générateur éolien.Un prototype de GSDE d'une puissance d'1MVA a été dimensionné, optimisé et fabriqué. Tout d'abord, le prototype a servi à la validation du modèle multi-physique. En plus la réalisation des essais sur deux étapes (avant et après le collage des aimants permanents) a montré l'apport énergétique du GSDE par rapport au GSPS
295

Reikalavimų specifikavimo šablonų pagrindu analizė ir programinis prototipas / Analysis of requirements specification using templates and programme prototype

Zinkevičius, Egidijus 04 March 2009 (has links)
Reikalavimų inžinerija yra bene svarbiausias etapas informacinės sistemos kūrime. Tik tikslus reikalavimų specifikavimo proceso valdymas leis sėkmingai projektuoti, realizuoti ir įdiegti informacines sistemas kompiuterizuojamose srityse. Dažnai neefektyvus reikalavimų rinkimo procesas tampa projekto nesėkmės ar programinės įrangos defekto pagrindu. Be to, aptiktų netikslumų pašalinimo kaina kyla eksponentiškai, kai jie atrandami vėlyvosiose projekto stadijose. Todėl įmonės ar asmenys, siekiantys pagerinti projekto kokybę ir produktyvumą, turėtų ypatingai atkreipti dėmesį į reikalavimų valdymo procesą. Pastebėta, jog reikalavimų specifikavimo procesas vis labiau kompiuterizuojamas, o reikalavimų valdymo įrankių bei šablonų naudojimas gerina reikalavimų specifikacijos ir būsimo produkto kokybę. Šis magistrinis darbas yra skirtas reikalavimų specifikavimo šablonų pagrindu eksperimentiniam tyrimui ir jo vertinimui. / The usage of computers takes more important place in our modern life. It was noticed that more and more enterprises use requirement management tools and specification templates to increase quality of requirement specification and projects. Very often ineffective requirements-gathering processes are the source of project failures and software defects. In addition, the cost of fixing defects rises exponentially as their discovery occurs later in the development process. However, a solid requirements process is fundamental to an effective overall process, and companies seeking increased quality and productivity should start with the requirements process. The intention of this work is to make the experimental research of requirements specification using templates and evaluate it.
296

Swedish Dimensional Adjectives / Svenska dimensionsadjektiv

Vogel, Anna January 2004 (has links)
The purpose of this study is to give a thorough and detailed account and analysis of the semantics of twelve Swedish dimensional adjectives: hög ’high/tall’, låg ’low’, bred ’broad/wide’, smal ’narrow’ vid ’broad’, trång ’narrow’, tjock ’thick’, tunn ’thin’, djup ’deep’, grund ’narrow’, lång ’long’ and kort ’short’. Focus has been placed on their spatial, non-metaphorical sense. The study was written within the framework of cognitive linguistics, where lexical definitions may be given in terms of prototypical and peripheral uses. Four sources of data have been considered: a corpus, consisting of contemporary fiction, an elicitation test, designed for the purpose, dictionary articles on the pertinent adjectives, and the author's own linguistic intuition as a native speaker. The methodology has involved categorisation of combinations of adjective and noun, based upon three major themes: orientation, function, and shape. In order to determine prototypical uses, precedence has been given to the outcome of the elicitation test over the corpus search. For both sources, frequency has played an important part. The ranking of senses as stated in the dictionary articles has also been considered. The results indicate that the dimensional adjectives differ quite markedly from each other, as opposed to a structural view where the adjectives traditionally have been regarded as forming a neat patchwork. Adjectives overlap each other for some uses (högt gräs ’high grass’, långt gräs ’long grass’ and even djupt gräs ’deep grass’), while there are also situations in which no dimensional adjective can describe an object. Furthermore, adjectives forming pairs, such as djup – grund ’deep – shallow’, do not exhibit full antonymy, despite the fact that dimensional adjectives are traditionally cited as examples par excellence concerning antonymy.
297

Elektros tinklo valdymo laboratorinio stendo prototipas / Laboratory equipment prototype for electrical network control

Jučas, Tomas 02 July 2012 (has links)
Parengtas bakalauro baigiamasis darbas yra skirtas suprojektuoti ir pagaminti automatinio rezervo įjungimo skydo prototipą, kurį būtų galima naudoti laboratoriniams darbams universitete.Šio darbo paskirtis yra papildyti elektros aparatų discipliną dar vienu, dažnai sutinkamu ir naudojamu visame pasaulyje stendu, paaiškinant jo veikimo principą, galimybes. Darbe aiškiai yra išdėstomos visos stendo dalys, stendui keliami reikalavimai, parodomos principinė ir valdymo schemos, paaiškinamas detalus veikimas, stendo valdiklio programos algoritmas. Taip pat supažindinama su Lucas-neulle mokomuoju dviejų atskirų tiekimo linijų stendu, parodant visas jo sudedamąsias dalis ir jas trumpai paaiškinant. / ATS helps to avoid serious problems in healthcare facilities for example by the same time when surgery is being held to save human lives and power supply interference occurs, it safely automatically switches power supply mains with no effect to the user. In industry it helps to avoid any power supply problems which every single of them could lead to destruction of expensive machinery or even harm people. Considering problems occurring in power supply lines, this was a great inspiration to produce automatic transfer switch prototype as my Bachelors degree thesis. Since Electrical Engineering Department had no real ATS system prototype before, it will surely supply existing basis and will help students to gain useful experience. Furthermore, all the details about ATS are expounded and will lead to full understanding of the system.
298

MULTIPLE CHANNEL COHERENT AMPLITUDE MODULATED (AM) TIME DIVISION MULTIPLEXING (TDM) SOFTWARE DEFINED RADIO (SDR) RECEIVER

Alluri, Veerendra Bhargav 01 January 2008 (has links)
It is often required in communication and navigation systems to be able to receive signals from multiple stations simultaneously. A common practice to do this is to use multiple hardware resources; a different set of resources for each station. In this thesis, a Coherent Amplitude Modulated (AM) receiver system was developed based on Software Defined Radio (SDR) technology enabling reception of multiple signals using hardware resources needed only for one station. The receiver system architecture employs Time Division Multiplexing (TDM) to share the single hardware resource among multiple streams of data. The architecture is designed so that it can be minimally modified to support any number of stations. The Verilog Hardware Description Language (HDL) was used to capture the receiver system architecture and design. The design and architecture are initially validated using HDL post-synthesis and post-implementation simulation. In addition, the receiver system architecture and design were implemented to a Xilinx Field Programmable Gate Array (FPGA) technology prototyping board for experimental testing and final validation.
299

Conception et intégration de microsystèmes sur un cylindre pour la mesure de ses déformations : application à un outil du domaine de la santé

Yang, Wenbin 24 November 2011 (has links) (PDF)
L'objectif de cette thèse est de développer un cylindre instrumenté pour mesurer sa déflexion dans les applications médicales. Deux types de matériaux sont utilisés pour le cylindre : l'acier inoxydable et le NiTi. Des microjauges sont réparties le long du cylindre pour mesurer en temps réel sa déformation, permettant ainsi de guider le cylindre à sa destination envisagée dans un geste chirurgical. Plusieurs approches pour la mesure de déformation sont présentées et comparées, et la mesure de déformation par les microjauges piézorésistives semiconductrices intégrées sur le cylindre paraît la méthode optimale en tenant compte de la sensibilité, la compatibilité biomédicale et la faisabilité en microfabrication. Des analyses théoriques et par méthode d'éléments finis sont effectués pour analyser le comportement mécanique du cylindre en flexion mais aussi pour positionner et dimensionner les microjauges piézorésistives sur le cylindre. Un premier prototype a été réalisé et caractérisé pour vérifier la fonctionnalité de notre système.La réalisation des microjauges sur les cylindres se déroule par la microfabrication en salle blanche. Le germanium est utilisé comme le matériau piézorésistif. A cause de la spécificité géométrique des cylindres en tant que le substrat de la microfabrication, de nombreuses modifications sont apportées au procédé de fabrication 'standard' pour le dépôt et l'usinage des matériaux en surface du substrat métallique courbe. Le résultat de microfabrication est présenté, ainsi que l'analyse et les améliorations éventuelles du procédé actuel.
300

Emotion lexicon in the Sepedi, Xitsonga and Tshivenda language groups in South Africa : the impact of culture on emotion / T. Nicholls

Nicholls, Tanja January 2008 (has links)
Thesis (M.A. (Industrial Psychology))--North-West University, Potchefstroom Campus, 2008.

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