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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.
181

Analysis Of Exhaust Waste Heat Recovery Techniques From Stationary Power Generation Engines Using Organic Rankine Cycles

Sham, Devin Krishna 13 December 2008 (has links)
Strict emissions legislation and energy security debates have spurred extensive research in alternative fuels and renewable energies. Literature research has shown the need for improvements in internal combustion engines (ICE) due to their low efficiencies. Significant gains in efficiency can be accomplished with the use of waste heat recovery (WHR) techniques. Organic rankine cycles (ORC) with turbocompounding harness the waste heat from an ICE to improve efficiency and fuel economy while reducing brake-specific emissions. A mathematical model was developed to explore the potential gains in 1st and 2nd law efficiencies. The model approaches the evaluations of the ORC from a practical and a theoretical method. The practical method in evaluation 1 limits the outlet exhaust gas temperatures from the evaporator to prevent the formation of condensation. The performance of the ORC is then evaluated and compared to the evaluation 2. In the theoretical method, in evaluation 2, the effect of pinch point on the evaporator and the entire cycle was analyzed. This analysis was conducted for R113, a dry fluid, and propane, a wet fluid, in order to analyze the differences in the two types of fluids. R113 showed a 13% – 22% and a 6% – 14.7% increase in 1st and 2nd law efficiencies, respectively. Propane showed a 9% – 17.4% and a 2% – 8.5% increase in 1st and 2nd law efficiencies, respectively. It was also shown that as the pinch point temperature decreases the 2nd law efficiencies increased. It was concluded that use of ORC with turbocompounding is an effective method for waste heat recovery in order to increase ICE efficiency.
182

Critical survey of mathematical business-cycle models and an improved aggregative model /

Smith, Elmer Louis January 1953 (has links)
No description available.
183

The effects of government policy on business cycles and productivity growth /

Jun, Sangjoon January 1994 (has links)
No description available.
184

Exploring the Influences of Intergenerational Pregnancies on Teenage Girls, Ages 16 - 19

Greensberry, Tynika 01 January 2018 (has links)
Generational cycles of teenage pregnancy trend among many families create economic, social, and health problems on teen parents and their families. Scholarly literature includes quantitative studies addressing the issue of teenage pregnancy but there is not many qualitative studies about the family cycle of teenage pregnancy among a highly-concentrated area of African American females in the Southern region of the United States. The life history theory and the socialization and social control theories of the intergenerational transmission of early childbearing served as the theoretical framework.. A qualitative case study is designed to identify factors that contributed to generational cycles of teenage pregnancy among families in the Southern region of the United States. Data were collected using questionnaires from 3 family triads of teenage mothers. Data were analyzed and display tables were created. The results indicated that participants had a lack of knowledge of proper contraceptive use and experienced peer pressure to engage in sexual behaviors. Teenagers looked at their mothers and sister's pregnancy in a favorable way making their pregnancy acceptable within families. Most participants felt teenagers should wait before becoming pregnant. Participants felt teenage mothers could overcome obstacles associated with teenage pregnancies. Pregnancy prevention programs may benefit from the results of this study through parenting programs to teach mothers, who were pregnant in their teen age, how to communicate with their teenage daughters about their sexual experiences.
185

A la recherche du cycle perdu mise en place des cycles d'apprentissage dans les écoles primaires de trois pays, Belgique, France, Québec /

Kahn, Sabine Bourdoncle, Raymond. January 2007 (has links) (PDF)
Reproduction de : Thèse de doctorat : Sciences de l'éducation : Lille 3 : 2007. / Résumés en français et en anglais. Titre provenant de l'écran-titre. Bibliographie. Notes bibliographiques.
186

Croissance, cycles longs et répartition /

Grangeas, Geneviève. January 1991 (has links)
Th. État--Sci. écon.--Paris 2, 1989. / Bibliogr. p. 293-312. Index.
187

The relationship between media spend and business cycles

Desai-Gossel, Yolande Angeline 05 1900 (has links)
Research report presented to the Unisa School of Business Leadership / The results of the study show that as posited in the research statement, media spend is positive in relation to both the direct and indirect business cycles variables. This pattern of increased media spend is only maintained during the up-phases of the business cycle, but tends to level off during the down-phases.
188

L'amour et la mesure dans l'oeuvre d'Albert Camus

Mc Cabe, Alexandre January 2010 (has links)
À sa mort, accidentelle et tragique, Albert Camus, qui n'a alors que 47 ans, laisse derrière lui une oeuvre inachevée. Trois ans après la réception du prix Nobel de littérature de 1957, l'écrivain croyait que son oeuvre était encore à faire.À preuve, quelques mois avant sa mort, Camus avait amorcé ce qu'il entrevoyait comme le troisième cycle de son oeuvre. Après l'avoir fait pour l'absurde et la révolte, Camus comptait consacrer un essai, une pièce de théâtre et un roman à la thématique de l'amour (les cycles étant ainsi constitués). Le premier homme, manuscrit publié par sa fille Catherine en 1994, soit 34 ans après sa mort, est malheureusement la seule trace concrète de ce qu'aurait pu devenir ce troisième cycle. Ce silence, trop précoce, laisse de nombreuses questions sur le cours nouveau qu'auraient pris les écrits d'Albert Camus.À défaut d'en connaître un jour la substance, il est possible d'en deviner les préoccupations et les intuitions contenues entres autres dans les notes laissées par l'écrivain et dans le développement même de l'oeuvre camusienne. Au moment de bâtir son troisième cycle, Camus s'était déjà attaché à l'amour. Dès sa jeunesse, l'écrivain, fidèle à quelques intuitions fondatrices de sa pensée, avait déjà reconnu en l'amour une racine essentielle. Nous avons tenté, à travers ce mémoire portant sur l'amour dans l'oeuvre d'Albert Camus, de réfléchir à la place qu'a occupée cette thématique dans ses écrits. Reprenant trois définitions tirées du lexique grec, Éros, Philia et Agapè, nous avons cherché dans l'oeuvre de Camus les multiples manifestations de l'amour. La lecture qui a découlé de cette"grille" d'analyse, souple, mais selon nous pertinente, donne un aperçu éclairant des questionnements qu'a eus l'écrivain en regard de l'amour tout au long de sa vie et plus particulièrement dans les dernières années de celle-ci (le récit du roman Le premier homme, bien qu'il soit inachevé, le confirme). L'amour maternel, l'amour du monde, l'amour des femmes, la solidarité et l'amitié sont autant de visages que Camus a donnés à l'amour dans ses écrits. Nous nous sommes employés dans ce mémoire à distinguer ces différentes formes d'amour et à les replacer dans leur contexte particulier.
189

Doctoral thesis recital (voice, baritone)

Eakin, Chance 10 October 2014 (has links)
Winterreise : D. 911 / Franz Schubert. / text
190

Enhanced virtual manufacturing : advanced digital mock-up technology with simulation variances

Oscarsson, Jan January 2000 (has links)
No description available.

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