O aumento da demanda por água potável em função do crescimento populacional, vem sendo objeto de estudo de diversos pesquisadores que buscam meios de otimizar o uso desse recurso. Desse modo, ao longo dos anos os equipamentos sanitários foram sendo aperfeiçoados para tornarem-se mais eficientes. Uma preocupação é o impacto nos ramais e coletores de sistemas prediais de esgotos sanitários, uma vez que os componentes economizadores ao demandarem menos água em sua operação, retornam vazões menores para a rede predial de esgoto sanitário e, consequentemente, geram ondas menores que impactam negativamente na autolimpeza dos condutos horizontais. Nesse sentido, o objetivo da pesquisa foi investigar, em laboratório, as vazões e profundidades da lâmina d´água do escoamento em ramais e coletores do sistema de esgotos sanitários de edifícios residenciais unifamiliares, tendo em vista a redução de diâmetros de 100 mm para 75 mm. A pesquisa foi realizada em laboratório vertical, onde foi montada uma configuração típica de um banheiro residencial, localizada no pavimento superior. Foram utilizadas bacias sanitárias com volume nominal de descarga de 6 L e 4,8 L, um chuveiro com vazão constante de 0,20 L/s e um lavatório com vazão constante de 0,15 L/s. As bacias sanitárias foram ensaiadas para calibração, segundo a NBR 15097 (ABNT, 2011) e ambas obtiveram resultados satisfatórios em todos os requisitos dessa norma. Foram variados os diâmetros dos ramais e coletores prediais de 100 mm para 75 mm, com e sem a contribuição da vazão em regime permanente de 0,35 L/s proveniente de um chuveiro e um lavatório e as declividades variadas em 0%, 1% e 2% nos ramais e 1%, 2% e 3% nos coletores de esgoto. Avaliou-se a influência dos parâmetros declividade, volume de descarga, presença ou não de vazão em regime permanente e diâmetro da tubulação, sobre a velocidade de escoamento da água. Concluiu-se que a redução dos diâmetros dos ramais e coletores de esgoto e a redução do volume de descarga de 6 L para 4,8 L contribuíram para o aumento da velocidade da onda sob as condições de estudo em todo o trecho ensaiado, ou seja, no trecho compreendido entre a bacia sanitária e o tubo de queda e ao longo de todo comprimento de 3 m do coletor de esgoto predial. Não foi estudada a influência da variação dos parâmetros sobre a velocidade de onda em trechos além do coletor de esgoto predial. Sob as condições de estudo, observou-se que a declividade não influencia, de maneira geral, no desempenho do sistema nos trechos ensaiados. A presença de uma vazão em regime permanente contribui para amortizar a energia da onda de descarga da bacia sanitária no ramal de descarga e consequentemente, reduz a velocidade de escoamento da água, o que pode contribuir para a piora do requisito de autolimpeza neste trecho da tubulação. No coletor de esgoto, não foi possível concluir que a presença de vazão em regime permanente tem impacto sobre a velocidade de escoamento da água. Por fim, conclui-se ser possível a redução dos diâmetros dos ramais e coletores do sistema predial de esgoto sanitário. / The increase in the demand for drinking water due to the population growth has been the object of study of several researchers who seek ways to optimize the use of this resource. In this way, over the years sanitary equipment has been improved to become more efficient. One concern is the impact on drains and main drains of building drainage system, since the economizing components, while using less water in their operation, return smaller flows to the sanitary sewage network and consequently lead to the formation of smaller waves that contribute to the self-cleaning of pipes. In this sense, the objective of the research was to investigate, in the laboratory, the flows and the depths of the flow in drains and main drains of residential building drainage system, in order to reduce diameters from 100 mm to 75 mm. The research was carried out in a vertical laboratory, where a typical configuration of a residential bathroom located on the second floor of a two story building was set up. A toilet with a nominal discharge volume of 6 L and 4,8L, a shower with a constant flow rate of 0.20 L/s and a lavatory with a constant flow rate of 0.15 L/s were used. The toilets were tested according to NBR15097 (ABNT, 2011) for calibration and both obtained satisfactory results in all the requirements of this standard. The diameters of the drains and main drains were varied from 100 mm to 75 mm with and without the contribution of the continuous flow rate of 0.35 L/s from a shower and lavatory and the slopes varying in 0%, 1% and 2% in the drains and 1%, 2% and 3% in the main drain. The influence of the parameters like slope, discharge volume, presence or not of continuous flow rate and pipe diameter, on the water flow velocity were evaluated. It was concluded that the reduction of the diameters of the drains and main drains and the reduction of the volume of discharge from 6 L to 4.8 L contribute to the increase of the velocity of the wave in the whole parts of the drain and main drain. It was not studied the influence of the variation of the parameters on the wave velocity on parts beyond the main drain. It was observed that the slope variation does not influence in general performance of the system. The presence of a continuous flow rate contributes to amortize the discharge wave energy from the toilet at the drains and consequently reduces the flow velocity of the water, which may contribute on deterioration of the self-cleaning requirements in this section of the pipeline. In the main drain, it was not possible to conclude that the presence of permanent flow has an impact on the flow velocity of the water.

Deep foundations constructed in liquefiable soils require specialized design. The design engineer of such foundations must consider the effects of liquefaction on the foundation and overlying structure, such as excessive settlement, loss of skin friction at the soil-pile interface, and the development of downdrag on the pile. Controlled blasting was employed to liquefy a loose, saturated sand in order to test the liquefaction prevention capabilities of full-scale, vertical composite earthquake (EQ) drains and to investigate the development of downdrag on full-scale test piles. Blasting produced liquefaction at a test site without EQ drains which eventually resulted in 270 mm of settlement. Liquefaction caused the skin friction on the test pile to decrease to zero immediately following blasting. As pore pressures dissipated and the sand settled, negative skin friction developed, with a maximum magnitude of about onehalf of the positive skin friction. Blasting also produced liquefaction at a site with drains but the settlement was reduced to 225 mm, a decrease of 17% relative to the untreated site. Nevertheless, the dissipation rate dramatically increased. Skin friction did not decrease to zero in the liquefied sand and negative skin friction increased to a value equal to the positive skin friction in the liquefied layer. The computer software, FEQDrain, was utilized to develop a calibrated model of the soil profile using pore pressure and settlement data measured during blast testing. This model was then used to simulate drainage systems with smaller drain spacing and larger drain diameter. Results indicated that pore pressures and settlement could be limited to levels acceptable for many applications. However, development of downdrag on deep foundations would not likely be prevented. EQ drains provide an attractive method of liquefaction mitigation. Furthermore, liquefaction can cause significant amount of downdrag on pile foundations which should be accounted for in deep foundation design.

published_or_final_version / Public Administration / Master / Master of Public Administration

Cette thèse travail s'articule autour des deux phénomènes : le capital humain et la migrationdes qualifiés. Les arguments consolidant le choix de cette interaction tiennent d'une part au constat selonlequel le capital humain constitue pour le Liban la seule matière première parce qu'il nedispose pas de ressources naturelles ni d'autres matières premières pouvant favoriser sondéveloppement; et d'autre part à la fatalité d'émigrer en l'absence de débouchés.La thèse est composée de trois parties. Dans la première partie, sont extraits de l'abondantelittérature les principaux traits liés au capital humain tels que son apport à l'accroissement ducapital et de la production de long terme et donc à la croissance du pays considéré; sont étayéspar la suite les motivations de la fuite des cerveaux et leurs effets sur les pays de départ(développé) et d'accueil (sous développé).La deuxième partie est destinée à décrire dans l'économie libanaise, les facteurs de générationdu capital, les niveaux d'emploi des qualifiés et l'émigration des qualifiés.La troisième partie est consacrée au modèle qui combine ces deux phénomènes en vue demettre en relief leur interaction. Ce modèle s'inscrit dans le cadre des travaux traitant dudrainage des cerveaux à l'aide d'une économie à générations imbriquées où sont représentésles choix des consommateurs et ceux du producteur, il met l'accent sur la divergence d'intérêt,vis à vis des migrants qualifiés, entre les pays source d'émigration et les pays d'accueil.Ce modèle a le mérite de relier les effets micro-économiques caractérisés par un choixindividuel de se former et/ou de migrer aux conséquences macro-économiques du mouvementmigratoire qui en résultent en analysant les revenus des agents, leur niveau d'emploi, le stockde capital et la production de long terme, et le bien être collectif.La résolution du modèle donne la quantité optimale de cette migration sélective. Cettequantité est explicitée pour les pays de départ et d'accueil dans une optique de long termeselon des situations de concurrence pure et parfaite et de syndicalisation des qualifiés. Les résultats numériques obtenus confirment clairement le constat suivant : les pays d'accueilreceveur d'immigrants qualifiés en bénéficie nettement, tandis que le pays source convoyeurd'émigrants se soumet à une ponction de l'un de ses facteurs les plus productifs. Ces résultatspermettent en outre de dresser pour les deux pays un tableau comparatif des salaires, desniveaux d'emploi, des biens être individuels et collectifs, du capital et du produit.Les différentes comparaisons établies des valeurs numériques laissent présager un moyend'action par le décideur politique du pays source d'émigration, en vue d'atténuer les effetsnéfastes de cette fuite des cerveaux. Ce moyen peut se réaliser, d'une part, grâce à despolitiques favorables à l'organisation des qualifiés au sein d'un groupe de pression ; et d'autrepart, en orientant l'émigration des qualifiés vers les pays dont l'économie est la plus libérale. / This thesis focuses on two phenomena: human capital and skilled migration.Such a choice is consolidated by the observation that on the one hand, humancapital is for Lebanon the only raw material given that it has no other resourcesof any kind that can promote its development, and on the other hand theinevitability of migration in the absence of opportunities.This thesis consists of three parts. In the first one, we extract from the abundantliterature the main features related to human capital, such as its contribution tothe growth of long-term capital and long-term production and therefore thegrowth of the considered country. Then, we study in detail the motivations ofbrain drain and its impact on source countries (underdeveloped) and hostcountries (developed).The second part is intended to describe in the Lebanese economy, factors ofgeneration of human capital, skilled employment levels, and skilled workersemigration.The third part is devoted to a model that combines these two phenomena inorder to highlight their interaction. This model is part of the work dealing withbrain drain using an overlapping generation economy in which are representedthe choices of consumers and producers. This model emphasizes the divergenceof interest towards skilled migrants, between source of emigration and hostcountries.This model has the merit of linking microeconomic effects characterized by anindividual choice of training to become skilled and of migrating, to themacroeconomic consequences of migratory movements, through an analysis ofagents' income and their employment level, long-term capital stock, long-termproduction, and welfare.Resolving the model gives the optimal quantity of this selective migration. Thisquantity is made explicit for source and host countries in a long-term perspectivefollowing pure and perfect competition situation and unionization of skilledworkers.The numerical results clearly confirm the following observation: the hostcountry clearly benefits from these skilled immigrants while the source countryis subject to the drain of one of its most production factors. These results alsoallow us to make for both countries a comparison of wages, employment levels,individual and collective welfare, capital and product.Comparisons of different numerical values suggest a means of action by thepolicymaker in the source country to mitigate the negative effects of the braindrain. This method can be achieved, on the one hand, through policiesfavourable to the qualified organization within a pressure group, and on theother hand, by directing skilled emigration to countries whose economy is mostliberal.

Thesis (M.A.(International Relations))--University of the Witwatersrand, Faculty of Humanities, 2016. / Today, it is estimated that annually, 70,000 skilled Africans depart their nations of origin to pursue professional and educational opportunities abroad. Many leaders, policymakers and developmental practitioners believe that this steady stream of emigrants—commonly referred to as brain drain—has a substantial impact on the ability of African nations to develop. As such, brain drain is rapidly becoming one of the most salient issues on the African development agenda. Conventional wisdom had it that once nations improved their political, economic and social conditions, brain drain would abate. Yet, some countries, which have succeededin advancing socio-economic reforms and political freedoms, are seeing an increase in skilled emigration. The West African nation of Ghana is one nation that is experiencing this problem, to the detriment of key areas such as education and healthcare. In an effort to curtail the impact of brain drain on development, several entities have undertaken initiatives to mitigate the effects of the phenomenon.This research will assess efforts to ameliorate the effects of brain drain in Ghana. Specifically, it examinestwo programs facilitated by the International Organization for Migration—the Return of Qualified African Nationals initiative and Migration for Development in Africa—as well as interventions by the Republic of Ghana. The purpose of the study is to better understand the objectives of these brain gain initiatives, how the programs are facilitated and their impact in order to extrapolate lessons that can assist future actors in formulating more effective measures to combat brain drain. / GR2017

Student Number : 0010372Y - MEd research report - School of Education - Faculty of Humanities / This study aims to investigate the experiences, problems and challenges faced by Foreign Faculty at the University of the Witwatersrand (Wits), with a special focus on how both the institution and the Foreign Faculty address them. The broader focus of the study is to examine and explore how universities address the challenge of internationalisation at the faculty level. An increase of faculty from Africa at an institutional level highlights the changing features of North to South and South to South faculty mobility, within an increasingly international and globalised world. While Foreign Faculty are accepted into internationally acclaimed universities (such as Wits), the study reveals the limited nature of the knowledge base documenting the experiences of Foreign Faculty in South African Universities. The research indicates that in spite of high level qualifications and research experience many Foreign Faculty are required to accept middle-level lecturer and senior lecturer positions. Findings also indicate that Foreign Faculty often experience a variety of challenges as a result of moving from one country / system to another. This study represents a contribution towards the debate on the employment of Foreign Faculty.

Ethiopia suffers from a medical shortage or brain drainthat has severely affected its already fragile health care system. The country has a very low physician-to-population ratio,whilemany in the medical community continue to leave in great numbers. Aphenomenological approach was used in this study to explore the lived experiences of medical doctors who have left Ethiopia, with contemporary migration theory serving as the conceptual framework. The central research question focused onwhy Ethiopian medical doctors leave their country and what can be done to retain them. Participants were 10 medical doctors of Ethiopian origin who live and practice medicine in the Washington, DC metropolitan area. Participantswere purposively selected, and in-depth interviews and a focus group discussion were used to collect data from them. The study followed Moustakas' recommendations for phenomenological analysis, which representeda modification of the Stevick-Colaizzi-Keen method. The themes that emerged during data analysis have economic, political, professional, and personal dimensions. The findings includelow pay, lack of professional development, poor working conditions, the threat of political persecution, fear of contracting HIV, and inability to participate in health care decision-making. Recommendations accordingly include offering pay raises and fringe benefits, creating opportunities for professional development, improving working conditions, and limiting political interference in the health care system. Implications for positive social change include the fact that stemming the outflow of medical doctors could help save the lives of thousands of Ethiopians threatenedby preventable and curable diseases.

Thesis (M. P. A.)--University of Hong Kong, 2007. / Title proper from title frame. Also available in printed format.

<p>This thesis focuses on the widely acknowledged so-called brain drain controversy. More concretely on developments in the traditional brain drain literature towards a new shift, claiming the brain gain effect, as an alternative to the brain drain effect, that emigration may bring to a source country. The research investigates not only the obvious direct loss effects – the so called brain drain – but also the possibility of more subtle indirect beneficial effects.</p>

This research investigates the drivers that pushed Returned Non Resident Indians(RNRIs) to come back to their homeland and their potential contribution, through the knowledgeand competences acquired by studying and working abroad, to the Firms that hire them.We used a qualitative method pursued through semi-structured non-standardized interviews withexperts of the topic and RNRIs. Furthermore, in order to have better insights, we looked at thebackground of the top management of 8 top IT Indian companies and at newspaper coverage.It resulted that RNRIs come back mainly to be closer to their families and because of a combinationof economic decline in the West and booming economy in India, thus leading to a better lifestyle.Moreover, we found indication of the contribution presented to Firms’ by knowledge and skills andgained interesting insights on the future trends of the Diaspora.However, our findings cannot be considered as conclusive, due to the small size of the sample wehad access to. The research topic needs further research.