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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.
211

Data mining of market information to assess at-home pork demand

Asatryan, Armen A. 30 September 2004 (has links)
This study analyzes the economic and demographic patterns of at-home pork consumption for representative individuals over 18 years of age in the United States. Three data sets purchased by the National Pork Board (NPB) are mined for this purpose: (1) National Eating Trends (NET) data from National Panel Diary (NPD) on individuals' intake and their demographic characteristics; (2) weekly retail prices for fresh meats and fresh pork cuts from FreshLook; and (3) weekly retail prices for processed pork products from A.C. Nielsen. Heckman sample selection models are used to find demographic, health, and attitudinal/lifestyle patterns of consumption of twelve fresh and processed pork products as well as beef, chicken, and seafood. In the fall, individuals have a higher probability of eating beef, chicken, pork tenderloin, and bacon, but a lower probability of eating fresh seafood, canned ham, and smoked ham relative to the spring. The New England region has the highest likelihood of eating fresh pork, beef, chicken, seafood, pork roasts, pork tenderloin, and pork hotdogs. Blacks, on average, eat more fresh and processed pork, chicken, pork sausage, bacon, and canned ham, but less beef relative to whites. Concern about serving food with fat is negatively related with the likelihood of eating processed pork, lunchmeat, ham, and bacon, but it is positively related with the likelihood of eating pork hotdogs. A three-stage selectivity-adjusted censored LA/AIDS model is developed and estimated to find demand-price relationships for: (1) fresh meats (pork, beef, chicken, and seafood) and (2) nine fresh and processed pork cuts. However, aggregate fresh meats are substitutes for each other in at-home market, but there are substantial complementarities between pork cuts. Pork sausage is the major competitor for the processed products, pork roasts and pork tenderloin, but a major complement for pork ribs. There is relatively week substitutability between pork and beef, and relatively strong substitutability between pork and chicken and between beef and chicken. This could suggest opportunities for some joint marketing efforts between pork and beef commodity interests. This information can be used as a guide for marketing strategists for targeting and promotion as well as for category management of the disaggregated pork products.
212

Stratégies d'apprentissage et variations de performance : du passage de la théorie à la pratique des étudiantes en techniques d'orthèses visuelles

Cloutier, Danielle 03 1900 (has links) (PDF)
Les programmes d'études au collégial présentent des activités de stages dont les objectifs sont directement liés à l'intégration et au transfert des apprentissages. Cependant, les enseignants remarquent souvent chez les étudiants des difficultés de rappel des connaissances en situation d'action ou de stage et cela se manifeste, entre autres, par les variations de performance qu'obtiennent ces étudiants, entre les situations théoriques et pratiques (de stage). Bien qu'ils n'abordent pas directement cette problématique, les écrits ont permis de cibler certains éléments clés potentiellement pertinents pour l'étude de ce phénomène. En considérant le transfert des apprentissages comme concept de base puisque qu'il s'articule autour de la réutilisation des connaissances dans un nouveau contexte, les stratégies d'apprentissage se sont avérées être l'élément le plus prometteur pour aborder le problème. Cette recherche s'est donc intéressée au fonctionnement stratégique d'étudiantes en techniques d'orthèses visuelles face aux modalités d'apprentissage et aux façons d'aborder les situations d'évaluation selon qu'elles aient obtenu des résultats similaires ou différents aux examens théoriques et pratiques. Les données ont été recueillies à l'aide de deux outils : un questionnaire et des entretiens semi-dirigés. Au terme de l'étude, il a été possible de dresser un profil stratégique des étudiantes selon leurs résultats aux examens théoriques et pratiques. Les données permettent surtout de constater que la stratégie anticiper est une façon de faire déterminante lors de l'encodage des connaissances puisqu'elle permet des actions garantes de meilleures performances aux examens. Enfin, cette étude a montré la pertinence de s'intéresser aux processus et aux activités réelles mises en action lors de l'encodage des connaissances et lors des examens, pour permettre une meilleure compréhension des facteurs qui sont en jeu dans la performance des étudiants. Elle a fait valoir également l'importance d'avoir recours à l'entretien comme mode de cueillette de données puisqu'il accorde aux participants le droit d'exprimer beaucoup plus de détails sur leurs façons de faire et ainsi de nuancer les résultats. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : stratégies d'apprentissage, théorie, pratique, encodage.
213

High Efficiency Two-Stage GaN Power Amplifier with Improved Linearity

Khan, Amreen January 2013 (has links)
The trade-off between linearity and efficiency is the key limiting factor to wideband power amplifier design. Current wireless research focuses much of its effort on building power amplifiers with the two aforementioned criteria going hand in hand to build an optimal design. This thesis investigates the sources of nonlinearity associated with GaN high electron mobility transistors (HEMT), and their subsequent effects on the linearity metrics of the power amplifier. The investigation began with an analysis of the sources of nonlinearity, and then a design-based approach to mitigate those sources of nonlinearity was developed. This design approach was compared with existing trends in power amplifier design. The device technology used in the design was CREE GaN HEMT (45W and 6W). In this report, a systematic approach to designing a two stage power amplifier is discussed, and analyzed for design of linear and highly efficient power amplifiers for base stations. The designed power amplifier consists of two stages: a driver stage and a power stage. The driver stage aimed to linearize the power stage by using circuit analysis and transistor properties along with providing the necessary gain. The power stage was built to complement the driver stage and to achieve high efficiency for the power amplifier. An inter-stage matching network placed between the two stages allowed for the required matching of impedances; transmission lines in the bias feed controlled the harmonic impedances for optimal performance without disrupting performance at fundamental frequencies. This approach effectively improved, and maintained, high efficiency over 200MHz of bandwidth. The design approach was simulated and fabricated in order to test the feasibility of linear power amplifier operation with the use of digital pre-distortion (DPD). The fabricated prototype achieved about 70% peak efficiency over the bandwidth and maintained linearity above 40dBc adjacent channel leakage ratio (ACLR) and below 3% error vector magnitude (EVM). The measurement results indicated that the need for DPD was eliminated when the power amplifier was operating in back-off at the center frequency (800MHz). This thesis compares the prototyped design with existing multistage designs which use linear drivers. The report provides conclusions derive from measurement results and bandwidth limitations faced throughout the course of the design. Lastly, potential research directions, which may allow researchers to overcome the limitations of this design, are discussed.
214

Toxicity of chemically dispersed crude oil to early life stages of Atlantic herring (Clupea harengus)

McIntosh, Stephen E 28 April 2009 (has links)
To minimize the damage caused by oil spills, responders may chemically disperse floating oil into the underlying water before it contacts shorelines and wildlife. Quantifying this strategy’s net ecological and commercial benefits requires an analysis of its effects on subsurface ecosystems and biota. Unfortunately, spill-responders have little empirical data on which to base such an analysis. Herein I report the effects of dispersed oil to early life stages of Atlantic herring (Clupea harengus). Medium South American crude oil (MESA) dispersed with Corexit 9500 caused blue sac disease (BSD) in embryos, but not in free-swimming embryos. The ages of embryos were negatively correlated with their sensitivity to oil, making those that were freshly fertilized the most sensitive. However, sensitivity was also high after hatch. Free-swimming embryos displayed signs of narcosis following brief exposure to dispersed oil. Gametes were also tested; dispersed oil dramatically impaired fertilization success. Toxicity was a function of concentration and duration of exposure, as well as of the life stage exposed. When the duration of exposure was < 24 h, gametes and free-swimming embryos were the most sensitive life stages (i.e. responded to the lowest concentrations). For durations > 24 h, young embryos (< 1 day old) were most sensitive. The results are presented as toxicity models that incorporate developmental stage, oil concentration, and exposure duration. Current effects-forecasting models for oil dispersion are based on published chronic toxicity data, which do not account for the effects of exposure duration and developmental events on toxicity. Thus, the results will better-enable modelers to estimate the effects of realistic exposures to dispersed oil in various locations, including spawning shoals. / Thesis (Master, Biology) -- Queen's University, 2009-04-26 12:55:12.266
215

The Experience of the Older Adult With End-Stage Renal Disease on Hemodialysis

CORRIGAN, REBECCA 15 September 2011 (has links)
Background: The growth in the number of individuals with end-stage renal disease has implications in terms of both the health of individuals, especially older adults (aged 65 years and older), and the capacity of the health care system to provide adequate treatment needed by these patients. Much has been written regarding the pathophysiology of end-stage renal disease as well as how modern advances in technology have contributed to the ‘dialysis world’. However, the literature is sparse in relation to how older adults experience end-stage renal disease and the technological complexity of dialysis in their daily lives. Objective: The purpose of this study was to explore the meaning of being hemodialysis-dependent for the older adult living with end-stage renal disease. Method: A descriptive method using a qualitative interviewing approach was used. Systematic focused thematic analysis guided by the Crisis of Physical Illness conceptual model allowed for the findings to surface. Data sources included individual interviews, direct observation of participants and the hemodialysis unit, along with field notes. A purposive sample of nine participants was obtained from two different hemodialysis units, both operated by Kingston General Hospital. Data were analyzed using the Colaizzi method. Findings: Five themes were identified by the participants: The Will to Live, Recognition of a Lifetime Commitment, Learning to Live with Technology, The Yin and Yang of Dialysis, and Transcending Dialysis. Conclusions: End-stage renal disease and thrice weekly hemodialysis treatment have an impact on the daily life of older adults and their ability to cope with the changes. This study revealed that despite the restrictions of being on hemodialysis, all of the participants had the will to live and some expressed the need for further education using a variety of strategies that would meet the specific needs of this population. A more in-depth understanding of how older adults experience hemodialysis is needed to provide adequate care/resources for this special population. / Thesis (Master, Nursing) -- Queen's University, 2011-09-15 13:02:28.548
216

Living with end-stage heart failure: an interpretive phenomenological study

Love, Reid Brian 29 August 2012 (has links)
A qualitative phenomenological study incorporating Photovoice was conducted to gain insight into the lived experience of patients with end-stage heart failure (ESHF). Seven participants were recruited and in-depth open-ended interviews were conducted with all participants. Three of the seven informants also opted to take part in the Photovoice portion of the project. “Working to preserve a sense of self” emerged as the essence of living with ESHF and was supported by three themes: i) the work of managing a failing and unreliable body, ii) the work of choreographing daily living; and iii) the work of charting the final chapter of one’s life. The findings from this study provide healthcare professionals with empirically grounded information and insights about the needs and everyday challenges individuals living with ESHF experience, and how clinicians can best support them. Such information is essential in order to plan meaningful, holistic, evidence-based care for ESHF patients.
217

New spaces of art, design and performance : Alfred Roller and the Vienna Secession 1897-1905

Silverthorne, Diane January 2010 (has links)
No description available.
218

Mother Courage and her children : a production

Morgan, Robert L. January 1968 (has links)
There is no abstract available for this thesis.
219

Problems in the design and technical direction of Jean Cocteau's Orph�ee as translated by Carl Wildmen

Slattery, Kenneth Martin January 1965 (has links)
There is no abstract available for this thesis.
220

Impact of IT on the Role of a Community of Practice Moderator in the Coalescing Stage of Development

Piepkorn, Farnaz Barvarz 01 January 2011 (has links)
This dissertation uses case study research to evaluate the impact of Information Technology (IT) on the moderator's role in directing a community of practice (CoP) in its Coalescing stage of development. Ten CoPs were studied. While each of these CoPs is in a different stage of development, the analysis focuses on the Coalescing stage because it is considered the most critical. A detailed case study of each CoP, including a survey of moderators and members, and interviews with moderators is presented. Analysis of these cases indicated that use of IT -- defined as communication, software, and hardware tools -- has a reciprocal effect on the role of the moderator. In other words, a moderator can achieve CoP goals and conduct its activities more efficiently and effectively by use of various IT tools. A moderator's competence and inclination to using IT tools also affects his or her role and the way he or she conducts the activities and plans to achieve the CoP goals. Those moderators who used IT tools to conduct their CoP's activities perceived their CoPs to be more successful than those who did not. Other factors such as company support, moderator's position and influence in the company, and the resources available to the CoP were the deciding factors on the moderator's role in facilitating a successful CoP. This dissertation concludes with a list of future research possibilities, obstacles to moderators, and improvement opportunities for large companies with several CoPs. All of the research studies on communities of practice so far have assumed that each company has only one CoP. This dissertation not only provides insight to a company with various CoPs, but it also offers a comparison study among different CoPs within the same company.

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