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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.
141

Preparation of the Syndiotactic Polystyrene Copolymer by Chemical Modifications

Chen, Yu-Pin 03 June 2003 (has links)
The main object of this study is to explore the possibility of using metallocene catalyst and reagent toe preparation syndiotactic polystyrene (sPS) framework connected with different polymer segments. Despite its enhanced thermal stability, the stereo-regular sPS generally has poor miscibility with other conventional polymers, which substantially limits its use in commerce. Therefore, chemical modifications on sPS were attempted in this study to hopefully introduce polar chain segments into the olefinic sPS chains and to possibly vary its properties and so, its miscibility with other polymers. Here, a novel metallocene catalyst prepared from (
142

Den lojala kunden – finns den? : Vilka faktorer påverkar kundens attityd och beteende och leder dessa faktorer till butikslojalitet?

Lennartson, Ninnie, Molnemark, Ulrika January 2010 (has links)
No description available.
143

Providing Informational Support to HIV+ Women in a Virtual Environment: A Case Study Comparing the Effects of Virtual Reality and Paper Media for Content Delivery

Brown, Sarah 01 January 2008 (has links)
South Africa has one of the highest HIV+ prevalence rates in the world [1]. Furthermore, social support is beneficial to HIV+ people. Informational support is a type of social support which is used to increase one’s knowledge base [2]. Hayes et al. state that informational support is especially beneficial for those in the early stages of HIV infection [3]. Computer technologies have been used successfully in providing informational support to their users. However, virtual reality (VR) is a relatively unexplored technology in South Africa, and we feel it is a highly appropriate medium for a context where users have little or no prior computing experience. Traditionally, computer interfaces require users to have a learned skillset, but a VR interface does not necessarily require this as it maps more directly to users’ natural interaction techniques with the real world. A key benefit of a virtual environment (VE) is the interactivity and user involvement that it offers through a high degree of navigation and interaction with objects [4]. VR may, initially, seem to be an expensive technology to use in a developing country but it is possible to make use of desktop VR on a consumer-grade PC relatively affordably. This dissertation presents a comparison of the effects of two media, VR and paper (i.e. pamphlets) in communicating supportive information to an HIV+ sample group. We created a VE to provide social and informational support for HIV+ people in the South African context. The design of the VE placed emphasis on creating a typically South African space which users could recognize and find familiar. Our research focused on two rooms containing virtual agents and points of possible interaction: the lounge and the kitchen. In the lounge, a HIV/Aids support group was simulated while the kitchen contained two areas which presented nutritional informational support: Diet and Cleanliness & Hygiene. We conducted a pre- post-test study with 22 HIV+ women at two clinics in Cape Town. Participants were randomly assigned into one of three groups. One group experienced the informational VE (VE), one group received information pamphlets (Text), the control group who received no information until the end of the study (Ctrl). Participants attended three experiment meetings over a five week period. Participants completed two 3-day food diaries and completed questionnaires that provided measurement for two sets of variables: Food Safety Behaviours (a measure of knowledge of correct food and water safety practices to prevent food-borne illnesses) and Dietary Quality (measure of the diet quality – in terms of quantity, variety, water intake and vitamin supplements, as well as specific food items for the prevention of stomach ailments, a common complaint of HIV infection). While we found no differences between the Text and Ctrl groups, the VE group showed a significant improvement in consuming two (of three) specific food items recommended for the prevention of stomach complaints. This is a particularly striking result given that more than half the participants stated that they routinely did not have enough money to buy food let alone specific healthy foods. The area that contained the information related to stomach complaints was the last imagery experienced by all VE participants. That it was the only area that showed improvement highlights how careful VE authors should be in choosing the actual content for the environment, as well as how that content is delivered. Despite very minimal computing experience and only short training sessions, all participants mentioned that they found the VE easy to use and enjoyed their experience of it. Our results show that VR can indeed be used to deliver informational content to HIV+ women in South Africa.
144

Performance Benchmarking Physical and Virtual Linux Environments

Fisher, Mario 01 January 2012 (has links)
Virtualisation is a method of partitioning one physical computer into multiple “virtual” computers, giving each the appearance and capabilities of running on its own dedicated hardware. Each virtual system functions as a full-fledged computer and can be independently shutdown and restarted. Xen is a form of paravirtualisation developed by the University of Cambridge Computer Laboratory and is available under both a free and commercial license. Performance results comparing Xen to native Linux as well as to other virtualisation tools such as VMWare and User Mode Linux (UML) were published in the paper "Xen and the Art of Virtualization" at the Symposium on Operating Systems Principles in October 2003 by (Barham et al, 2003). (Clark et al, 2004) performed a similar study and produced similar results. In this thesis, a similar performance analysis of Xen is undertaken and also extended to include the performance analysis of OpenVZ, an alternative open source virtualisation technology. This study made explicit use of open-source software and commodity hardware.
145

4-Tiazolidinono junginių sintezė, analizė ir mikrobiologinis tyrimas / Biologically active compounds of 4-thiazolidinone synthesis, analysis and microbiological testing

Mazurkevičiūtė, Agnė 18 June 2014 (has links)
Darbo tikslas: nustatyti galimą nifumezino ir į jį panašių junginių struktūros-aktyvumo ryšį. Tyrimo metodai: susintetintų nifumezino analogų preliminarūs antimikrobinio aktyvumo tyrimai in vitro ir antimikrobinio aktyvumo prognozė PASS programa. Tyrimo rezultatai: atlikus antimikrobinio aktyvumo tyrimus in vitro nustatyta, kad junginiai AM-3 ir AM-4 yra praktiškai neaktyvūs, kai koncentracija 500 µg/ml. Junginiai AM-3-1 ir AM-4-1 veikia S. aureus, E. faecalis, S. epidermidis. AM-5 aktyvus prieš S. aureus ir B. subtillis. Nė vienas iš susintetintų junginių nėra aktyvus prieš P. aeruginosa, P. mirabilis ir E. coli. Atlikus kompiuterinį aktyvumo prognozavimą PASS programa, nustatyta, kad stipriausias antibakterinis poveikis prognozuojamas AM-3-1 ir AM-4-1 junginiams (Pa>0,4). Priešgrybelinis poveikis prognozuotas junginiui AM-3-1. Prognozuojamas didžiausias toksiškumas (Pa>0,6) AM-3-1 ir AM-4-1 junginiams. AM-4 prognozuojami 4 nepageidaujami farmakologiniai poveikiai, o AM-5 – 6. Tyrimo išvados: Nustatyta, kad antimikrobiniam poveikiui yra svarbus nitrofuraldehido pakaitas 5-oje padėtyje ir sulfadimidino pakaitas. Sulfadimidino vieta rodanino žiede (3-ia ar 4-a padėtis) reikšmingos įtakos neturi, tačiau dalinai skiriasi junginių aktyvumas prieš skirtingas bakterijų rūšis. PASS programa gali nuspėti junginių aktyvumą ir pagreitinti galimų veiklių junginių atranką ir kryptingą sintezę. / Aim of study: to identify potential nifumezine and similar compounds structure- activity relationship. Study methods: antimicrobial activity tests in vitro and prognosis of antimicrobial activity by PASS program. Study results: antimicrobial activity tests in vitro showed that the compouds AM-3 and AM-4 is inactive at concentration 500 µg/ml. Compounds AM-3-1 and AM-4-1 are active against S. aureus, E. faecalis, S. epidermidis. None of the synthesized compounds are not active against P. aeruginosa, P. mirabilis and E. coli. Activity prognosis by PASS program showed that the strongest antibacterial effect predisted compound AM-3-1 and AM-4-1, but these compouds have also the bigest risk to be toxic. Conclusions: it was found that the nitrofuraldehyde in 5-position is important to antimicrobial effects. The position of sulfadimidine (3rd or 4th position)is not significantly affected in rhodanine ring, bet different compounds could be active against different type of bacteria. PASS program can predict the activity of compounds.
146

Characteristics of 4-H members attending camp from selected counties and their implications to planning camp programs

Daentl, Donovan A., January 1967 (has links)
Thesis (M.S.)--University of Wisconsin, 1967. / Extension Repository Collection. Typescript (carbon copy). Includes autobiographical sketch of author. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 180-183).
147

Survey of training needs of Illinois local 4-H club leaders

Lyon, Richard O., January 1958 (has links)
Thesis (M.S.)--University of Wisconsin, 1958. / Extension Repository Collection. Typescript (carbon copy). Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaf 80).
148

Factors related to 4-H club participation by higher and lower socio-economic status youth in Adams County, Wisconsin

Spencer Maurice J., January 1966 (has links)
Thesis (M.S.)--University of Wisconsin, 1966. / Extension Repository Collection. Typescript (carbon copy). Autobiographical sketch. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 131-137).
149

Relationship of personality traits of 4-H members to awards received

Stodola, Robert A., January 1965 (has links)
Thesis (M.S.)--University of Wisconsin, 1965. / Extension Repository Collection. Typescript (carbon copy). Autobiographical sketch. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 71-72).
150

Behavior changes resulting from two leadership approaches to teaching clothing selection to older 4-H youth

Pingel, Virginia. January 1967 (has links)
Thesis (M.S.)--University of Wisconsin, 1967. / Extension Repository Collection. Typescript (carbon copy). eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 114-119).

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