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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.
11

Um estudo teórico da transferência de calor em fluídos confinados em regiões cilíndricas /

Pantuzi, Thais Alessandra. January 2006 (has links)
Orientador: Luiz Roberto Carrocci / Banca: Rubens Alves Dias / Banca: Messias Borges Silva / Resumo: Esse trabalho mostra modelos teóricos com soluções numéricas para o comportamento térmico de um armazenador de calor sensível usando água como fluído de trabalho. Um modelo bidimensional baseado nas equações de conservação de massa, conservação da quantidade de movimento e conservação de energia é usado para simular o fenômeno da estratificação. Para a solução numérica foi utilizado o método de diferenças finitas. Foi analisada a degradação da estratificação na condição de resfriamento natural com tanque estacionário, e alguns parâmetros que influenciam os processos de carregamento e descarregamento também foram simulados pela solução numérica. Em uma comparação feita entre um armazenador estratificado e uma armazenador homogêneo, mostrou-se que a eficiência do armazenador estratificado é maior. A razão de aspecto igual a quatro foi a melhor encontrada para a operação de extração. O estudo da velocidade, nas operações de carregamento e descarregamento, mostrou que com o aumento da mesma o tempo de operação diminui, mas este aumento tem um limite para que não ocorra uma diminuição da eficiência. / Abstract: This work shows theoretical models with solutions for the thermal behavior of a storing one of sensible heat using water as fluid of work. A based bidimensional model in the equations of conservation of the mass, conservation of the amount of movement and conservation of the energy is used to simulate the phenomenon of the stratification. For the numerical solution the method of finite differences was used. The degradation of the stratification in the condition of natural cooling with stationary tank was analyzed, and some parameters that also influence the shipment processes and unloading had been simulated by the numerical solution. In storing a storing comparison made between estratificado and a homogeneous one, one revealed that the estratificado efficiency of the storing one is bigger. The reason of equal aspect the four was the best one found for the operation of extration. The study of the speed, in the operations of shipment and unloading, it showed that with the increase of the same o running time it diminishes, but this increase has a limit so that a reduction of the efficiency does not occur. / Mestre
12

Discrimination and social adjustment of 'new arrival women' from Mainland China

TSOI, San Kiu, Sunday 01 July 2002 (has links)
This research examines the scope and the extent of discrimination experienced by (New Arrival Women) NAW as well as its impact on their social adjustment in Hong Kong Special Administration Region (HKSAR). It has been argued that discrimination slow down the adjustment process. Institutionalized discrimination and individual discrimination are examined in relation to NAW social adjustment in the HKSAR society. The research framework is based on the concepts of institutionalized and individual discriminations. Unfair Government policies being seen as a socio-structural factor results in institutionalized discrimination while the unsatisfactory outcomes arising from the interaction between NAW and LPRs (Local Permanent Residents) brings about individual discrimination. These experiences have brought a sense of alienation and separation from the host population. This study is based on panel study that lasted from January 2001 through March 2002. In-depth interviews to NAW from Mainland China to Hong Kong were conducted twice within one year. The interviewees include 33 NAW who entered the HKSAR with one-way permit in the last 5 years under the family reunion policy. The time interval between the first and the second interview was at least ten months. Participant observation of two NAW for 9 months was also conducted to complement the interviews. Findings indicate that institutionalized discrimination arising from government policies such as policies on accreditation, Identity Card and public housing eligibility have adverse effect on the social adjustment of NAW. Furthermore, individual discrimination, as a result of NAW shortcomings in language fluency, differences in life style and dressing style, are manifested in cheating (non-verbal behaviour), scolding (verbal behaviour) and beating (violence). Another major observation is that individual discrimination, which may be attributed to the economic recession where NAW are regarded by LPRs as competitors in the sharing of the diminishing social resources such as jobs and other welfare facilities, gives rise to a sense of alienation and separation. However, proactive social service for NAW empowers their capability to adjustment in HKSAR, which enhance integration and assimilation to the receiving society. Surprisingly, wife abuse is found in NAW’s family. Concomitant to discrimination, NAW lacks support from the society and the family. Indeed, some experienced abuse in the homes, which challenges the notion that family provides social support. Their sense of powerlessness has becomes a catalyst for solidarity among themselves to face the unfavourable situation. In conclusion, institutionalized discrimination as well as individual discrimination do exist and have adverse effect to the social adjustment process of NAW typically reflected in alienation and separation from the host population.
13

The Impacts of a Food Pantry on College Students

Howell, Courtney 01 January 2022 (has links) (PDF)
The issue of food insecurity on college campuses has been explored in great depth in the last decade; however, there is much less research on the impacts of interventions such as food pantries. Some scholars suggest that food pantries alone are not enough to make an impact on food insecurity, asserting that, "not a single study has examined the effectiveness of food pantries at decreasing food insecurity on postsecondary education institutions" (Bruening, Argo, Payne-Sturges, and Laska 2017: 1788). This study aimed to gain insight into the student experience of using a food pantry and the impact that it has on their college experience. This study focused on what additional access to food and resources means to college students at a large, public, four-year institution. Interviews were conducted with twenty-eight UCF students who have used the Knights Pantry. The student experience using the pantry was explored, including entry to the pantry, barriers, how the pantry is used, and the emotions that students feel when using the pantry services. Further, the impact of the pantry on students was profound: students report more financial stability, more food security, and even, in some cases, better ability to perform in classes. In addition, a "ripple effect" of impact is seen, with services reaching others in the community, most often family members of students. Overall, this study serves as a model for future explorations of the impact of food insecurity interventions and provides the first insights into how additional food access impacts college students.
14

Stratified Neighborhoods, Stratified Schools: Intradistrict Transfer and Racial and Socioeconomic Stratification

Larsen, Elisabeth Stuart 21 April 2009 (has links) (PDF)
Intra-district transfer policies allow students to attend any school within a district and thus may have unique consequences for stratification within a district. If parents make choices based on common academic interests, this policy can create racial and socioeconomic integration across the schools in a district. However, socially motivated choices may lead to the creation of increasingly stratified zones. This study examines one urban school district with an intra-district transfer policy to examine if the schools in the district become more racially and economically stratified under the choice policy and if the level of stratification at family's zoned schools is correlated with participation in choice. Results show that families zoned to schools mirroring the district's diverse composition are more likely to participate in choice, suggesting that more factors than simple academically-based motivations guide choice behavior. Exploration of the levels of stratification in schools with and without the choice policy suggests that the overall trend is to maintain the level of stratification present in the residential areas. Although most changes under the choice policy are small in magnitude, the changes that do occur push the district towards increased stratification.
15

Determinants and Effects of Student Involvement at Elite Colleges and Universities in the United States

Michael, Joseph 13 October 2014 (has links)
No description available.
16

Self-Stratifying Coatings

Chen, Long 19 September 2013 (has links)
No description available.
17

When wealth matters: parental wealth and child outcomes

Campbell, Lori A. 11 December 2007 (has links)
No description available.
18

Les nouvelles migrations de travail intra-européennes : jeunes Polonais et Roumains au Royaume-Uni et en Espagne / Europe’s new labour migrations : Polish and Romanian young migrants in the United-Kingdom and in Spain

Flipo, Aurore 24 November 2014 (has links)
Cette thèse interroge l'existence et la définition de « nouvelles migrations de travail » en Europe à partir de l'analyse comparée des jeunes migrants Polonais et Roumains au Royaume-Uni et en Espagne. En adoptant une approche comparative et historique, elle montre d’abord que c'est la conjonction entre un espace économique inégal et une intégration économique avancée d'une part ; et la transformation des inégalités intranationales vis-à-vis de l'emploi d'autre part, qui explique la diversité des propensions à migrer dans les différents pays européens. En se plaçant ensuite du côté des pays d'accueil, elle montre la persistance de la segmentation du marché du travail et la pertinence de l'utilisation de cadres d'analyse transnationaux et sectoriels pour mettre en évidence l'existence de marchés d'emplois locaux globalisés. L'étude analyse également le processus de ségrégation professionnelle des migrants, dont les ressources personnelles (et en particulier l'origine sociale) conditionnent fortement les opportunités de mobilité sociale. Enfin, en analysant l’interaction entre mobilité, insertion professionnelle et passage à l’âge adulte, elle montre que la mobilité peut devenir une forme de précarité sociale marquée par une incertitude temporelle et spatiale. Au final, l'étude démontre la nécessité de distinguer les pratiques de mobilité, qui se caractérisent par une diversification sociale, des usages sociaux distincts, classés et classants, dans un champ de l'international transformé par la libre-circulation ; et les migrations de travail comme fait social, caractérisées par de fortes régularités historiques. / This dissertation investigates the definition and the characterization of “new” labor migrations within Europe. Based on a comparative analysis of young Polish and Romanian migrants in the United-Kingdom and in Spain, it uses both statistical data and qualitative analysis of migrants’ interviews. The analysis of patterns of migration within the European space shows that the diversity of national profiles can be explained by the convergence of an integrated but unequal economic space on one hand, and the rise of new intranational inequalities regarding the labor market, on the other hand. The analysis based on the countries of destination (the United-Kingdom and Spain) shows that labor market segmentation is still prevailing. It suggests that the transnational and sector-based approach is necessary to fully explain and identify globalised labor markets. The analysis also investigates the social process of segmentation and its impact on migrants’ occupational mobility, or the lack thereof. It shows that chances of mobility depend mainly on individual resources reflecting the social origin of migrants. Finally, the analysis of the links between professional integration, entry into adulthood and mobility suggests that mobility is also a kind of uncertainty, both time-related and space-related. As a conclusion, the study reveals the necessity of distinguishing between mobility practices, characterized by a growing diversity and distinct social uses in the transformed international field of free mobility; and contemporary labor migrations as a social fact, which includes in part intra-european migrations.
19

L’emploi du Temps dans "L’Emploi du temps" de Butor / Use of time in Butor's "L'Emploi du temps"

Gallon, Stéphane 05 April 2013 (has links)
Dans la perspective de réhabiliter la stylistique herméneutique, L’emploi du Temps dans L’Emploi du temps de Butor cherche à montrer comment le style non seulement permet d’entrevoir les Visions du Monde passées ou présentes mais contribue à mieux comprendre le monde et offre même des pistes éthiques aidant à dépasser crises et impasses.Puisque ramenant constamment aux mêmes faiscsèmes (sèmes inhérents à plusieurs stylèmes et se retrouvant à des niveaux d’analyse différents), les stylèmes des architextes, énonciations, récit, histoire et écriture de L’Emploi du temps révèlent en effet qu’au Temps linéaire traditionnel issu du judéochristianisme, de la pensée bourgeoise et de lamécanique classique, Butor substitue non pas comme certains de ses contemporains un Temps labyrinthique et absurde mais un Temps stratifié, un Temps rendant compte à la fois des acquis de la pensée mythique et de certaines des conceptu-alisations philosophiques de Kierkegaard, Bergson, Husserl, Heidegger, Sartre et Bachelard.Dépassant ces penseurs, prenant doublement à contre-pied Bergson, illustrant certaines des remarques d’Heidegger sur l’art, Butor en arrive même à mettre peu à peu en place, par le jeu complexe des stylèmes associés en faiscsèmes, un Temps structuré, spatial et musical. En découle un « emploi du Temps » bien moins anxiogène et tyrannique que celuique nous subissons depuis l’avènement de la révolution industrielle, un emploi du Temps qui aide à passer de l’inauthentique à l’authentique, donne épaisseur et poids aux actes, est source d’unification et de liberté, musicalise et poétise le réel, en un mot, permet de toucher du doigt monde, être et éternité / With a view to rehabilitating hermeneutic stylistics, L’emploi du Temps dans L’Emploi du temps de Butor seeks to show how style not only offers glimpses of past and present world views, but also enhances understanding of the world, even providing ethical pointers to help get over crises and deadlocks. Since they constantly bring us back to the same “faiscsèmes” (“asemeblies” ?) (semes inherent to several stylemes, found at different levels of analysis), the stylemes of the architexts, enunciations, accounts, story and writing of L’emploi du Temps reveal that instead of the traditional linear Time that comes from the Judeo-Christian view, bourgeois thinking and the classical physics/mecanics, Butor proposes, not like some of his contemporaries an absurd, labyrinthine Time, but a stratified Time, a Time reflecting both the experiences of mythical thought and some of the philosophical conceptualisations of Kierkegaard, Bergson, Husserl, Heidegger, Sartre and Bachelard. Going further than these thinkers and doubly opposing Bergson, illustrating certain comments made by Heidegger on art, Butor even comes gradually to install a structured, spatial and musical Time through a complex interplay of stylemes combined into sembeams. This gives rise to a much less stressful and tyrannical use of time than has been imposedsince the industrial revolution, a use of time that helps us move from the unauthentic to the authentic, gives substance and weight to actions, is a source of unification and freedom, makes reality musical and poetic, in a word, brings us closer to a full grasp of world, being and eternity
20

Effect of phosphorus placement in reduced tillage crop production

Martin, Kent Lee January 1900 (has links)
Doctor of Philosophy / Department of Agronomy / David B. Mengel / A number of questions are being raised concerning phosphorus (P) management as producers switch to minimum or no-tillage cropping systems. Benefits of P application are site specific and potential advantages need to be evaluated for each location. Deep band application effects on crop yield and soil P distribution have been studied, but conclusive results are lacking because of the complexity of environment and P placement interactions, particularly in moisture limited environments. Challenges in soil test sampling and interpretation have also affected P management in these reduced and no-tillage systems because of decreased confidence in soil test P data. The objectives of this research were to evaluate crop responses to P application rate and placement and to study the distribution of soil P concentration, both vertically and laterally at a number of locations in Kansas. This research shows that crop growth at the sites evaluated was not negatively affected by P stratification, which was present at all sites at the beginning of the study. Phosphorus placement methods (broadcast and deep band) did not have significant effects on P responses. However, P application was required to achieve maximum yields at sites with low soil P, but high P sites did not consistently respond to P application. When P fertilizer was broadcast, shallow soil depths continued to have high soil test P, while deep band application increased soil P in the 7.6 to 15 cm depth. The addition of starter application with deep banding of P generally resulted in a more even vertical distribution of soil P. Soil test P data also demonstrated that the presence of bands can be confirmed through soil sampling, but the confidence of soil test P data in a vertical and lateral stratified soil was decreased. Soil samples taken from the band area had highly variable P (high coefficient of variation) concentrations likely due to an inability to sample from within the P band or variability in P application. Soil sampling in these management systems proves to be challenging and will need further research to identify improved methods for soil test P sampling and interpretation.

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