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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.
321

The initial development and content validity of an Asperger's Syndrome self-screening instrument for adults

Fung, Karen 25 February 2011 (has links)
This research addresses the lack of an existing psychometrically sound Aspergers Syndrome self-screening instrument for adults. Initial instrument development procedures were carried out by creating an item pool using existing Asperger measures. Items were rewritten following common item writing rules suggested by several researchers as reference. Five new domains were created and the items were re-categorized. Expert panel of nine judges specialized in Psychometrics, ASD, School Psychology, and Speech-Language Pathology were asked to rate the relevancy of items to their domains in order to obtain evidence of content validity. These experts were chosen because of their relatedness to Aspergers Syndrome and their expertise in instrument development. First, the quality of the judges ratings were examined to identify any aberrant judges. Ratings were then analyzed using the remaining six judges using three descriptive and three quantitative methods to examine the representativeness and relevancy of each item to their domain. A total of 55 items were identified as satisfactory by the judges. The second part of this study was to compare the content validity analytical methods. It was concluded that the percentage agreement, the content validity index (CVI), and the content validity coefficients (VIK) were the best methods to use in selecting the satisfactory items. This research aims to bring more attention to the importance of psychometric properties in measures for the Autism Spectrum Disorder field. It also hope to shed some light on which content validity analyses would best be used under certain circumstances. Limitations of study and future directions were also discussed.
322

PÅVERKAR ÅLDER, KÖN OCH TRÄNINGSMÄNGD FMS? : En tvärsnittsstudie mellan Functional movement screen samt sf-36v2 Health survey

Gustafsson, Sofia, Jeanette, Backholm January 2012 (has links)
Regelbunden fysisk aktivitet motverkar en rad fysiska och mentala sjukdomar. Hälsovinster av fysisk aktivitet är bland annat en högre funktionell muskulär- och kardiovaskulär kapacitet samt en högre livskvalitet. Stillasittande och inaktivitet kan leda till övervikt, kardiovaskulära sjukdomar, cancer, psykosociala problem och metaboliska sjukdomar. Mellan män och kvinnor finns fysiologiska skillnader som visar sig i kroppsstorlek och muskelmassa. Detta ger generellt sett kvinnor mer flexibel fysik medan män är fysiskt starkare. WHOs rekommendationer om daglig fysisk aktivitet är 150 min/vecka av moderat aerobisk träning eller 75 min mer ansträngande aerobisk träning. Styrketräning som involverar större muskelgrupper rekommenderas i åldrarna 18-64.   Till hjälp att undersöka hypotesen har två oberoende test används. En skriftlig enkät, SF-36v2 Health Survey, samt ett fysiskt test, Functional Movement Screen. I denna studie undersöks huruvida det finns ett samband mellan en ökad träningsmängd och ett högre FMS-resultat samt om en högre ålder ger lägre FMS-resultat, oavsett kön. Vi tror oss även se ett samband mellan högre FMS-poäng och ett högre uppskattat mentalt och fysiskt mående. Testpersonerna (N:30) som deltog i studien var arbetande eller studerande män (N:15) och kvinnor (N:15) i åldrarna 20-65år. FMS-resultaten visade ingen signifikant skillnad mellan kön eller stigande ålder. Däremot ser vi signifikanta skillnader mellan könen vid specifika styrke- eller rörlighetstester i FMS. Kvinnorna visar tydligt via resultaten att de generellt har en mer flexibel fysik medan männen är starkare. Som slutsats av denna studie kan vi konstatera att FMS som testmetod är könsneutralt och kan användas på blandade populationer. Detta ger testmetoden en bred användbarhet på just en blandad population. Fler studier krävs för att få fram normerande poängsättning om FMS skall användas på medelmotionären.
323

Effects of terrain features on wave propagation: high-frequency techniques

Sarwar, Muhammad January 2009 (has links)
This Master thesis deals with wave propagation and starts with wave propagation basics. It briefly presents the theory for the diffraction over terrain obstacles and describes two different path loss models, the Hata model and a FFT-based model. The significance of this paper is that it gives the simulation results for the models mentioned above and presents a comparison between the results obtained from an empirical formula and the FFT-model. The comparison shows that the approach based on Fast Fourier Transform is good enough for prediction of the path loss and that it is a time efficient method.
324

Understanding and Development of Manufacturable Screen-Printed Contacts on High Sheet-Resistance Emitters for Low-Cost Silicon Solar Cells

Hilali, Mohamed M. 19 July 2005 (has links)
A simple cost-effective approach was proposed and successfully employed to fabricate high-quality screen-printed (SP) contacts to high sheet-resistance emitters (100 ohm/sq) to improve the Si solar cell efficiency. Device modeling was used to quantify the performance enhancement possible from the high sheet-resistance emitter for various cell designs. It was found that for performance enhancement from the high sheet-resistance emitter, certain cell design criteria must be satisfied. Model calculations showed that in order to achieve any performance enhancement over the conventional ~40 ohm/sq emitter, the high sheet resistance emitter solar cell must have a reasonably good (120,000 cm/s) or low front-surface recombination velocity (FSRV). Model calculations were also performed to establish requirements for high fill factors (FFs). The results showed that the series resistance should be less than 0.8 ohm-cm^2, the shunt resistance should be greater than 1000 ohm-cm^2, and the junction leakage current should be less than 25 nA/cm^2. Analytical microscopy and surface analysis techniques were used to study the Ag-Si contact interface of different SP Ag pastes. Physical and electrical properties of SP Ag thick-film contacts were studied and correlated to understand and achieve good-quality ohmic contacts to high sheet-resistance emitters for solar cells. This information was then used to define the criteria for high-quality screen-printed contacts. The role of paste constituents and firing scheme on contact quality were investigated to tailor the high-quality screen-printed contact interface structure that results in high performance solar cells. Results indicated that small particle size, high glass transition temperature, rapid firing and less aggressive glass frit help in producing high-quality contacts. Based on these results high-quality SP contacts with high FFs0.78 on high sheet-resistance emitters were achieved for the first time using a simple single-step firing process. This technology was applied to different substrates (monocrystalline and multicrystalline) and surfaces (textured and planar). Cell efficiencies of ~16.2% on low-cost EFG ribbon substrates were achieved on high sheet-resistance emitters with SP contacts. A record high-efficiency SP solar cell of 19% with textured high sheet-resistance emitter was also fabricated and modeled.
325

Selective Determination of Uric Acid in the Presence of Ascorbic Acid at Screen-Printed Carbon Electrode Modified with Electrochemically Pretreated Carbon Nanotube

Lin, Liang-Shian 02 September 2010 (has links)
none
326

An Experimental Study On The Performance Of Box Type Floating Breakwaters With Screens

Kurum, Mustafa Onur 01 July 2008 (has links) (PDF)
In the present thesis the performance of box type floating breakwaters (FBs) with screens under regular waves is examined experimentally in a wave flume. The experiments were conducted in the Coastal and Harbor Engineering Laboratory wave flume, Civil Engineering Department, Middle East Technical University, Ankara. The influence of incident wave characteristics and certain geometric characteristics, such as the width and draft of the structure, on its effciency is examined. Three different widths of the structure in combination with three different screen (draft) height, a total of nine different cases, of FBs are examined. Results related to transmission and reflection of the incident regular waves on the structure are presented. According to the results, for all structures drafts and structure widths, as h/L increase (wave period and wave height decreases) Kt values decrease. Also, Kt values obtained for chain moored floating breakwaters are larger than the Kt values of fixed cases consistently.
327

Optimization Of Metalization In Crystalline Silicon Solar Cells

Demircioglu, Olgu 01 August 2012 (has links) (PDF)
iv ABSTRACT OPTIMIZATION OF METALIZATION IN CRYSTALLINE SILICON SOLAR CELLS Demircioglu, Olgu M. Sc. Department of Micro and Nanotechnology Supervisor : Prof. Dr. Rasit Turan Co-Supervisor : Assist. Prof. Dr. H. Emrah &Uuml / nalan August 2012, 103 pages Production steps of crystalline silicon solar cells include several physical and chemical processes like etching, doping, annealing, nitride coating, metallization and firing of the metal contacts. Among these processes, the metallization plays a crucial role in the energy conversion performance of the cell. The quality of the metal layers used on the back and the front surface of the cell and the quality of the electrical contact they form with the underlying substrate have a detrimental effect on the amount of the power generated by the cell. All aspects of the metal layer, such as electrical resistivity, contact resistance, thickness, height and width of the finger layers need to be optimized very carefully for a successful solar cell operation. In this thesis, metallization steps within the crystalline silicon solar cell production were studied in the laboratories of Center for Solar Energy Research and Application (G&Uuml / NAM). Screen Printing method, which is the most common metallization technique in the industry, was used for the metal layer formation. With the exception of the initial experiments, 6
328

Cryptosporidium parvum: enhancing our understanding of its unique fatty acid metabolism and the elucidation of putative new inhibitors

Fritzler, Jason Michael 10 October 2008 (has links)
Cryptosporidium parvum is widely known for outbreaks within the immunocompetent population, as well its sometimes excruciating effects as an opportunistic agent in AIDS patients. Our understanding of the biology and host-parasite interactions of this parasitic protist is increasing at a rapid rate due to recent molecular and genetic advances. The topic of our research is in the area of C. parvum fatty acid metabolism, which is highly streamlined in this parasite. In addition to a type I fatty acid synthase (CpFAS1), C. parvum also possesses an enormous type I polyketide synthase (CpPKS1). Because of the size of this megasynthase, functional characterization of the complete enzyme is not possible. We have isolated and characterized the loading unit of CpPKS1 which contains an acyl-[acyl carrier protein (ACP)] ligase (AL) and an ACP. This unit is responsible for the overall substrate selection and initiation of polyketide production. Our data show that CpPKS1 prefers long-chain fatty acids with the highest specificity for arachidic acid (C20). Thus, the final polyketide product could contain as many as 34 carbons. Additionally, C. parvum possesses only a single fatty acid elongase. This family of enzymes serves a mechanism similar to FAS, and many have been found to be involved in de novo fatty acid synthesis in other organisms. After expressing this membrane protein in human cells, we have determined that it too prefers long-chain fatty acyl-CoAs which undergo only one round of elongation. This is in contrast to members of this enzyme family in other organisms that can initiate de novo synthesis from two- or four-carbon fatty acids via several rounds of elongation. Our lab has previously characterized the unique acyl-CoA binding protein (CpACBP1) from C. parvum. Molecular and biochemical data suggested that this enzyme may serve as a viable drug target. We have screened a library of known (and somewhat common) compounds against CpACBP1, and have isolated several potential compounds to be further examined for their ability to inhibit the growth of C. parvum.
329

Transparens i en deferred pipeline : <html /> / <html /> : <html />

Hanna, Stefan January 2010 (has links)
<p>Deferred shading är en renderingsteknik som har blivit allt mer populär i och med att hårdvaraukraven för tekniken inte längre är ett hinder. Ett problem med deferred shading är fortfarande hur transparenta objekt ska hanteras. Rapporten utvärderar två olika deferred pipelines som hanterar transparent geometri på olika sätt, de två renderingsmetoderna är <em>Inferred Lighting</em> samt <em>Light Pre Pass </em>med framåtrendering för hantering av transparent geometri.</p>
330

Web accessibility / Web accessibility

Strobel, Cornelia 30 September 2003 (has links) (PDF)
Workshop Mensch-Computer-Vernetzung Web Accessibility Gestaltung von Webseiten um eine Nutzung mit vielen verschiedenen Zugangsmgeräten (Scrennreader, Bildschirmlupe) und unter verschiedenen technischen Bedingungen (langsame Anbindung, veraltete Software, keine Farbe) weitestgehend uneingeschränkt zu ermöglichen.

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