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In this dissertation I will present and test a model linking actual applicant-interviewer demographic, human capital, and cultural capital similarity to an interviewer's recommendation to hire. Actual similarity is proposed to influence an interviewer's perceptions of similarity with an applicant. These perceptions, in turn, lead to the interviewer's perceptions of the applicant's Person-Organization (PO) fit and the applicant's Person-Job (PJ) fit. Two main mechanisms are proposed to mediate the relationship between an interviewer's perceptions of similarity and an interviewer's perceptions of an applicant's fit: liking and negative behavioral expectations. Lastly, both an interviewer's PO and PJ fit perceptions of an applicant are posited to influence the interviewer's recommendation to hire. A total of 118 interviewer-applicant dyads contacted through the Career Center Office at a University located in the southwestern United States participated in the study. Results partially support the model. An interviewer's perceptions of similarity with an applicant are positively related to an interviewer's fit evaluations. An interviewer's negative behavioral expectations of an applicant mediate this relationship. Furthermore, perceived similarity is positively related to an interviewer's liking of an applicant. In turn, liking is positively related to an interviewer's PO fit perceptions. However, liking does not function as a mediator between perceived similarity and fit evaluations. Finally, fit evaluations are positively related to hiring recommendations. I discuss the main implications of the study as well as strengths, limitations, and future research.

In this dissertation I will present and test a model linking actual applicant-interviewer demographic, human capital, and cultural capital similarity to an interviewer's recommendation to hire. Actual similarity is proposed to influence an interviewer's perceptions of similarity with an applicant. These perceptions, in turn, lead to the interviewer's perceptions of the applicant's Person-Organization (PO) fit and the applicant's Person-Job (PJ) fit. Two main mechanisms are proposed to mediate the relationship between an interviewer's perceptions of similarity and an interviewer's perceptions of an applicant's fit: liking and negative behavioral expectations. Lastly, both an interviewer's PO and PJ fit perceptions of an applicant are posited to influence the interviewer's recommendation to hire. A total of 118 interviewer-applicant dyads contacted through the Career Center Office at a University located in the southwestern United States participated in the study. Results partially support the model. An interviewer's perceptions of similarity with an applicant are positively related to an interviewer's fit evaluations. An interviewer's negative behavioral expectations of an applicant mediate this relationship. Furthermore, perceived similarity is positively related to an interviewer's liking of an applicant. In turn, liking is positively related to an interviewer's PO fit perceptions. However, liking does not function as a mediator between perceived similarity and fit evaluations. Finally, fit evaluations are positively related to hiring recommendations. I discuss the main implications of the study as well as strengths, limitations, and future research.

The main topic of this project is to do an energy study of the Mariners’ Church, ‘Sjömanskyrkan’, placed in the Centralplan of Gävle, Sweden. This is an old building built in the late 1800’s by the evangelic-lutheran missionaries and nowadays is used to realize different cultural activities such as concerts, meetings, workshops…   Energy is one of the most important points in the actual society. The fact that common energy sources are being depleted and the use of these resources produces a lot of contaminants have brought some many international crisis and conflicts. A big use of oil fuels can influence the government behavior and condition its laws and regulations. Nowadays, the majority of the countries want to reduce their fossil energy sources dependency, e. g. Sweden designed an energy commission in 2005 to make a report on how these uses of petroleum, natural gas and ‘fossil raw materials’ can be reduced until 2020. This project wants to follow this direction, providing some energy savings through the investment and renewal of old public buildings.   The aim of this project is to know how much and in which way this building uses the energy, locating its strong and weak points, and point out some different energy efficiency measures to improve the situation.   First of all, an energy balance has been realized. In the part of the heat gains the total energy use is 274 MWh / year. On the other hand the energy losses give a quantity of 273 MWh / year. The differences between both are the losses by infiltration, 1MWh / year. Most of this energy is lost because of the transmission, about a 95% of the energy losses. The age of the building and its old materials are the main reason for this out of proportion percentage. That’s why the main efficiency measures are referred to this part.   After this first analysis, some efficiency measures have been carried out. The most important are referred to the structural elements like walls, windows, roof and floor. All of these procedures can save 45% of the energy losses. This is evidence that old buildings and this in particular, are really bad insulated and have a lot of heat leakages. Also some behavior recommendations are given, like maintenance works and lightning improvements.

This thesis examines the transmission of sound through lightweight parallel plates, (plasterboard double wall partitions and timber floors). Statistical energy analysis was used to assess the importance of individual transmission paths and to determine the overall performance. Several different theoretical models were developed, the choice depending on the frequency range of interest and method of attachment of the plates, whether point or line, to the structural frame. It was found that for a line connected double wall there was very good agreement between the measured and predicted results, where the dominant transmission path was through the frame and the cavity path was weak. The transition frequency where the coupling changes from a line to a point connection is when the first half wavelength is able to fit between the spacings of the nails. For point connected double walls, where the transmission through the frame was weaker than for line connection, the cavity path was dominant unless there was absorption present. When the cavity was sufficiently deep, such that it behaved more like a room, the agreement between the measured and predicted results was good. As the cavity depth decreases the plates of the double wall are closer together and the agreement between the measured and predicted results were not as good. Detailed experiments were carried out to determine the transmission into the double wall cavities and isolated cavities. It was found that the transmission into an isolated cavity could be predicted well. However, for transmission into double wall cavities the existing theories could not predict transmission accurately when the cavity depth was small. Extensive parametric surveys were undertaken to analyse changes to the sound transmission through these structures when the material or design parameters are altered. The SEA models are able to identify the dominant mechanisms of transmission and will be a useful design tool in the design of lightweight partitions and timber floors.

Orientador: Arnaldo Cesar da Silva Walter / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-11T14:09:41Z (GMT). No. of bitstreams: 1 Mourad_AnnaLucia_D.pdf: 3110699 bytes, checksum: 49fe1b8b524a32979e74ac9c1dd156d2 (MD5) Previous issue date: 2008 / Resumo: A introdução do biodiesel no Brasil é motivada principalmente pela possibilidade de desenvolvimento econômico e. social para o país, com geração de emprego e renda, além dos beneficios ambientais decorrentes da substituição de recursos fósseis por renováveis. Embora o I programa tenha grande incentivo governamental, há dúvidas sobre a viabilidade econômica do mesmo e sobre seus reais benefícios. O programa prevê a obtenção do biocombustível a partir de diferentes oleaginosas como dendê, mamona, amendoim, soja, algodão, girassol, etc. Entretanto, em função da grande produção de soja no país (58,7 milhões de toneladas na safra de 2007/2008), aproximadamente 80% do volume total de biodiesel comercializado no país é produzido a partir da soja. O objetivo deste trabalho foi avaliar a cadeia produtiva de biodiesel de soja dentro de uma abordagem de ciclo de vida, envolvendo a etapa agrícola, a extração de óleo e a transesterificação do mesmo para obtenção do biocombustível, bem como determinar o balanço energético para a sua produção. O estudo envolveu coleta de dados em cinco fazendas produtoras de soja (localizadas no estado de São Paulo) e uma empresa produtora de biodiesel a partir de óleo de soja. Os dados relativos à etapa de extração do óleo foram estimados, principalmente, a partir de dados estatísticos representativos do setor produtivo de soja. O estudo revelou um balanço energético favorável para a produção do biodiesel de soja, ou seja, gera-se mais energia renovável do que se consome de energia fóssil. O balanço foi obtido considerando a alocação de 18% dos insumos necessários para a produção do óleo e de 82% para a obtenção do farelo de soja, valioso co-produto desta cadeia produtiva. A produção de biodiesel, que em sua essência visa substituir o diesel como combustível, entretanto, aumenta o uso do próprio diesel, pois o combustível fóssil é utilizado na operação das máquinas agrícolas e nas etapas de transporte. Os resultados obtidos mostram que a introdução do biodiesel na matriz energética do país tem impactos significativos no uso, na transformação e na ocupação de terras e nas emissões para a água e para o ar. Portanto, embora seja de origem renovável, também tem um custo ambiental, mas diferente dos combustíveis fósseis. Particularmente, a introdução do biodiesel a partir da soja, tem o beneficio de produzir um farelo altamente protéico, de elevado valor comercial como ingrediente para rações animais, e que, portanto, está indiretamente ligada a produção de carnes para alimentação humana. Assim, pode-se dizer que, tanto o biodiesel como o farelo resultante desta cadeia, tem fluxo estabelecido nos atuais padrões de consumo e uso do país. A glicerina gerada no processo, (aproximadamente 11 % da massa do biodiesel), não é atualmente consumi da, embora existam várias pesquisas em andamento para a sua valorização e uso. A soja, por suas características agronômicas, entretanto, não se configura como uma cultura. viável para pequenos produtores agrícolas, pois exige grandes extensões de terra e elevado grau de mecanização. Os resultados deste trabalho revelam diferentes aspectos desta cadeia produtiva que devem ser considerados e bem gerenciados para a condução do programa governamental / Abstract: The introduction ofbiodiesel in Brazil is mainly motivated by the possibility of economic and social development for the country, with employrnent and income generation, as well as environrnental benefits due t9 replacement of fossil fuels by renewable resources. Although biodiesel has great governrnent incentive, there are doubts about its economic viability and real a benefits. The governrnent plan includes manufacturing of this fuel from different crops such as palms, castor beans, peanuts, soybeans, coconuts, cotton and sunflower. However, due to the huge volume of soybean production in the country (58.7 million tons in 2007/08), approximately 80% of the total biodiesel volume is produced starting from this source. The objective of this study was to evaluate the soybean biodiesel chain in relation to its technical and economic aspects using a life cycle approach, including stages from agriculture, oil extraction and oil transesterificatibn to obtain biodiesel. Data was collected from five farrns located in São Paulo State and one industrial unit that produces soy methyl ester from soybean oiL Oil extraction was estimated mainly using statistical data from the Brazilian industry sector. A favorable energy balance was found for soybean production showing that more renewable energy is prQduced than fossil energy is consumed. This favorable balance was achieved with an allocation of 18% of total input for the oil production itself and 81 % to obtain soybean m~al, a valuable co-product of this productive chain. Although biodiesel is introduced to reduce depemence of fossil fuels, biodiesel production process actually increases the use of petroleurn diesel which is used in agricultural machinery and transport steps. Biodiesel introduction in the Brazilian energy grid have significant environrnental impacts such as land use, land transformation and emissions to air and Water. Therefore, although it has a renewable origin, biofuel also has an environmental cost, but different to that of fossil fuels. In particular, the production of biodiesel from soybeans has the benefit of high protein meal co-product generation that has great economic value as ingredient for animal feed. As a consequence, it has a direct link with meat production for human consumption. So, it is clear that both product (biofuel) and co product (meal) already have established markets. Glycerin generated in the process, (approximately 11 % of biodiesel mass) is not consumed in the internal market, although there are several developments for new viable uses. Soybean is not considered as a suitable crop for small farmers as it requires a high mechanization leveI and large extensions of land. The findings of this study show that different aspects of this productive chain must be considered to support important govemment policy decisions / Doutorado / Planejamento de Sistemas Energeticos / Doutor em Engenharia Mecânica

To support further technology development and to promote the growth of a renewable biofuels industry that will satisfy the stated expectations of anticipated energy needs, it is essential that energy production systems provide a net energy gain over the course of their lifetime. As a means to provide accurate analysis to the value of alternative energy systems this paper provides a mechanism to evaluate energy systems in terms of energy generation ratios that is in terms of existing analysis techniques utilized in existing energy generation areas, such as the oil industry. This paper also proposes techniques that help perform this net energy analysis in terms of the specific economy considering the infrastructure investment.

La méthode SEA (Statistical Energy Analysis) est une approche statistique de la vibroacoustique permettant de décrire les systèmes complexes en termes d'échanges d'énergies vibratoires et acoustiques. En moyennes et hautes fréquences, cette méthode se présente comme une alternative aux méthodes déterministes (coût des calculs dû au grand nombre de modes, de degrés de liberté, unicité de la solution) Néanmoins, son utilisation requiert la connaissance et le respect d'hypothèses fortes qui limitent son domaine d'application. Dans ce mémoire, les fondements de la SEA ont été examinés afin de discuter chaque hypothèse. Le champ diffus, l'équipartition de l’énergie modale, le couplage faible, l'influence des modes non résonants et l'excitation rain-on-the-roof sont les cinq hypothèses qui ont été abordées. Sur la base d'exemples simples (oscillateurs couplés, plaques couplées), les équivalences et leurs influences sur la qualité des résultats ont été étudiées pour contribuer à la clarification des hypothèses nécessaires à l'application de la SEA ct pour borner son domaine de validité SEA. / Statistical energy analysis is a statistical approach of vibroacoustics which allows to describe complex systems in terms of vibrational or acoustical energies. ln the high frequency range, this method constitutes an alternative to bypass the problems which can occur when applying deterministic methods (computation cost due to the large number of modes, the large number of degrees of freedom and the unicity of the solution). But SEA has numerous assumptions which are sometimes forgotten or misunderstood ln this thesis, foundations of SEA have been examined in order to discuss each assumption. Diffuse field, modal energy equipartition, weak coupling, the influence of non-resonant modes and the rain on the roof excitation are the five look up hypotheses. Based on simple examples (coupled oscillators, coupled plates), the possible equivalences and their influence on the quality of the results have been discussed to contribute to the clarification of the useful SEA assumptions and to mark out it's the validity domain.