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Computer Simulation Of Grain Boundary Grooving By Anisotropic Surface Drift Diffusion Due To Capillary, Electromigration And Elastostatic ForcesAkyildiz, Oncu 01 May 2010 (has links) (PDF)
The aim of this study is to develop a theoretical basis and to perform computational experiments for understanding the grain boundary (GB) grooving in polycrystalline thin film metallic conductors (interconnects) by anisotropic surface diffusion due to capillary, electromigration and elastostatic forces.
To this end, irreversible thermo&ndash / kinetics of surfaces and interfaces with triple junction singularities is elaborated, and the resulting well-posed moving boundary value problem is solved using the front&ndash / tracking method. To simulate the strain conditions of the interconnects during service, the problem is addressed within the framework of isotropic linear elasticity in two dimensions (plane strain condition). In the formulation of stress induced surface diffusion, not only the contribution due
to elastic strain energy density (ESED) but also that of the elastic dipole tensor interactions (EDTI) between the stress field and the mobile atomic species (monovacancies) is considered. In computation of the elastostatic and electrostatic fields the indirect boundary element method (IBEM) with constant and straight boundary elements is utilized. The resulted non&ndash / linear partial differential equation is solved numerically by Euler&rsquo / s method of finite differences.
The dynamic computer simulation experiments identify well known GB groove shapes and shed light on their growing kinetics. They also allow generating some scenarios under several conditions regarding to the applied force fields and/or physicochemical parameters.
The destruction of groove symmetry, termination of the groove penetration with isotropic surface diffusivity, ridge/slit formations with anisotropic diffusivity and the role played by the wetting parameter are all identified for electromigration conditions. The kinetics of accelerated groove deepening with an applied tensile stress is examined in connection with GB cavity growth models in the literature and a diffusive micro-crack formation is reported at the groove tip for high stresses. On the other hand, the use of EDTI provided a means to dynamically simulate GB ridges under compressive stress fields with surface diffusion. An incubation time for hillock growth and a crossover depth over which GB migration becomes energetically favorable is defined and discussed in this context.
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PamukSariaslan, Kubra Zeynep 01 September 2010 (has links) (PDF)
Kars is an ethnically diverse city located at the North East Turkey, neighboring Armenia. In the year 2002, Nobel laureate author Orhan Pamuk published a political-historical novel named Snow, the story of which is set in Kars. The book created a public debate on national and global scale about cutting edge questions of Turkey. This thesis aims to address these questions from the perspective of inhabitants of Kars, who had reacted fiercely to the representations in the book Snow. By focusing on identification and boundary negotiation processes of people in Kars, this thesis and presents an ethnography of Kars, which was achieved by application of grounded theory method and by discussing local perceptions of ethnicity, nationalism and secularism at the periphery of Turkey.
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Numerical heat transfer during partially-confined, confined, and free liquid jet impingement with rotation and chemical mechanical planarization process modelingLallave-Cortes, Jorge C 01 June 2009 (has links)
No description available.
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Essay 1: 'An Examination of the Efficiency, Foreclosure, and Collusion Rationales for Vertical Takeovers' Essay 2: 'Determinants of Firm Vertical Boundaries and Implications for Internal Capital Markets'Shenoy, Jaideep Ranjal 29 April 2009 (has links)
Essay 1: An Examination of the Efficiency, Foreclosure, and Collusion Rationales for Vertical Takeovers We investigate the efficiency, foreclosure, and collusion rationales for vertical integration using a large sample of vertical takeovers. The efficiency rationale posits that vertical integration prevents future holdup between non-integrated suppliers and customers. In contrast, the foreclosure and collusion rationales suggest that vertical integration harms competition. To distinguish between these hypotheses, we examine the wealth effects of the merging firms, acquirer rivals, target rivals, and corporate customers on announcement of vertical takeovers. Our univariate and cross-sectional results suggest that firms alter their vertical boundaries in a manner that is consistent with the efficiency rationale. Our tests do not find evidence supportive of the anti-competitive rationales for vertical integration. Essay 2: Determinants of Firm Vertical Boundaries and Implications for Internal Capital Markets In this paper, we investigate the determinants of vertical relatedness between business segments of multi-segment firms and how vertical relatedness affects the internal allocation of capital. Consistent with theory, we observe a higher degree of vertical relatedness between segments in environments likely to involve contracting problems. Further, there is a greater tendency for investments to flow towards segments with better investment opportunities as the degree of vertical relatedness between business segments in the firm increases. This indicates that internal capital markets function better in the presence of significant vertical relatedness between segments. This finding supports the Stein (1997) model, which suggests that the headquarters is able to do a better job of “winner-picking” when firms operate in related lines of businesses.
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Skundų žemės reformos klausimais nagrinėjimo organizaciniai-teisiniai aspektai Telšių apskrityje / Organizational and Juridical Aspects of Dealing with Complaints Related to the Land Reform in the Telšiai DistrictStulpinas, Kęstutis 03 June 2009 (has links)
Teisės aktais yra reguliuojamas visas, tiek privačios, tiek valstybinės žemės naudojimas. Žemės naudotojai privalo žemę naudoti taip, kaip numatyta teisės aktuose nepažeidžiant jų nuostatų. Žemės savininkai ir naudotojai privalo žinoti teisės aktų nustatytus reikalavimus – leidžiamą veiklą, jos apribojimus, savo teises, pareigas bei prievoles, taip pat – taikomas sankcijas už įstatymų pažeidimus. Priversti žemės savininkus ir naudotojus žemę naudoti pagal tikslinę žemės naudojimo paskirtį, būdą, pobūdį ir ją tausoti galima tik aktyviai vykdant valstybinę žemės naudojimo kontrolę, nevengiant surašyti administracinių teisės pažeidimų protokolų. Nors Telšių apskrityje nuosavybės teisių atkūrimo procesas baigiasi, tačiau vis dažniau iškyla nusiskundimų dėl riboženklių nebuvimo, projektuose numatytų ar nenumatytų privažiavimų prie sklypų, dėl ribų tarp gretimai besiribojančių sklypų savininkų. Klausimus, ar visuomet piliečiai skundžiasi pagrįstai, ar jie vykdo savo pareigas ir prievoles, nagrinėja apskrities viršininko administracija. Pagal Lietuvos Respublikos Apskrities valdymo įstatymo nuostatas apskrities viršininkas, neviršydamas savo įgaliojimų, nagrinėja fizinių bei juridinių asmenų pareiškimus bei prašymus ir priima dėl jų sprendimus. Atlikta anketinė apklausa parodė, kad su skundų tyrimu susijusios išlaidos valstybei turi būti kompensuojamos savininko lėšomis. / The law deeds control the use of both a private and public territories. The owners of the land must use a holding agreeably to the law and not violating its regulation. The owners and the users of a land must know the requirements of law articles: permissible activity and its restrictions, the rights, responsibilities and duties of the owner, also the penalties for violating the law. In order to lead the land owners to use their holdings agreeably to the objective purpose of the use and to save it, the national land use control has to be positively implemented, not avoiding to draw up the reports on violating the administrative rights. Although the restitution of proprietary rights in the district of Telšiai is almost finished, but there are still a lot of complaints about landmarks, approaches to the holdings, which are represented or not represented in the projects and for the boundaries between neighboring land owners. The Administration of the county chief analyses the validity of complaints of citizens and if the citizens are keeping their responsibilities and duties. According to the provisions of the law of the County Administration of Lithuanian Republic, the governor of the county staying within his authority deals with applications of legal persons and decreases it. The performed survey showed that the state expenses for the analysis of complaints have to be compensated by the owner.
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A Search for Maximal Diversity Amongst Paired Prisoner's Dilemma Strategiesvon Keitz, Michael 21 December 2011 (has links)
Previous research has identified linear boundaries within a normalized unit square for specific paired strategies within the iterated prisoner's dilemma schema. In this work, general methods of capturing linear boundaries are developed and demonstrated on a wider variety of paired strategies. The method is also tested using an alternate scoring method. An application of Burnside's Lemma simplifies the number of neighbourhood configurations to be considered. In addition, Shannon entropy is used as a means of evaluating diversity of agents evolved with different payoff matrices, by which one might locate a game that is as balanced as possible.
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Classification in high dimensional feature spaces / by H.O. van DykVan Dyk, Hendrik Oostewald January 2009 (has links)
In this dissertation we developed theoretical models to analyse Gaussian and multinomial distributions. The analysis is focused on classification in high dimensional feature spaces and provides a basis for dealing with issues such as data sparsity and feature selection (for Gaussian and multinomial distributions, two frequently used models for high dimensional applications). A Naïve Bayesian philosophy is followed to deal with issues associated with the curse of dimensionality. The core treatment on Gaussian and multinomial models consists of finding analytical expressions for classification error performances. Exact analytical expressions were found for calculating error rates of binary class systems with Gaussian features of arbitrary dimensionality and using any type of quadratic decision boundary (except for degenerate paraboloidal boundaries).
Similarly, computationally inexpensive (and approximate) analytical error rate expressions were derived for classifiers with multinomial models. Additional issues with regards to the curse of dimensionality that are specific to multinomial models (feature sparsity) were dealt with and tested on a text-based language identification problem for all eleven official languages of South Africa. / Thesis (M.Ing. (Computer Engineering))--North-West University, Potchefstroom Campus, 2009.
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Classification in high dimensional feature spaces / by H.O. van DykVan Dyk, Hendrik Oostewald January 2009 (has links)
In this dissertation we developed theoretical models to analyse Gaussian and multinomial distributions. The analysis is focused on classification in high dimensional feature spaces and provides a basis for dealing with issues such as data sparsity and feature selection (for Gaussian and multinomial distributions, two frequently used models for high dimensional applications). A Naïve Bayesian philosophy is followed to deal with issues associated with the curse of dimensionality. The core treatment on Gaussian and multinomial models consists of finding analytical expressions for classification error performances. Exact analytical expressions were found for calculating error rates of binary class systems with Gaussian features of arbitrary dimensionality and using any type of quadratic decision boundary (except for degenerate paraboloidal boundaries).
Similarly, computationally inexpensive (and approximate) analytical error rate expressions were derived for classifiers with multinomial models. Additional issues with regards to the curse of dimensionality that are specific to multinomial models (feature sparsity) were dealt with and tested on a text-based language identification problem for all eleven official languages of South Africa. / Thesis (M.Ing. (Computer Engineering))--North-West University, Potchefstroom Campus, 2009.
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The 'Other' Doctor : Boundary work within the Swedish medical professionSalmonsson, Lisa January 2014 (has links)
This thesis is about medical doctors with immigrant backgrounds who work in Sweden. Based on 15 qualitative interviews with medical doctors with immigrant backgrounds, this thesis explores the medical doctors’ feeling of professional belonging and boundary work. This thesis focuses mainly on the doctors’ experiences of being part of the Swedish medical profession while, at the same time, being regarded as ‘different’ from their Swedish medical counterparts. It starts off with the idea that medical doctors with immigrant backgrounds may have, or could be regarded as having, contradictory social positions. By virtue of being part of the Swedish medical profession, they belong to one of the most privileged groups in Swedish society. However, due to their immigrant background these doctors do not necessarily occupy a privileged position either within their profession or in society in general. This thesis shows that doctors with immigrant backgrounds feel that they are not perceived as full-fledged doctors, which seem related to how they are somewhat ‘othered'. The results show that these doctors cope with being seen as different from doctor with non-immigrant backgrounds, by using the notion of ‘migranthood’ as a resource in negotiations in everyday work life but they also do what they can to overcome the boundaries of ‘Swedishness’. Belonging should therefore be seen as having a formal and an informal side, as getting a Swedish license does not automatically mean that you feel belonging to, in this case, the Swedish medical profession. This seems to put doctors with immigrant backgrounds in a somewhat outsider within position, which seems having to do with boundaries between who is included in the ‘us’ and in the ‘them’. Lastly, these findings indicate that sociologists need to expand the understanding of professional groups to also include boundary work within these groups. In order to do so, this thesis argues that sociological theory on professional groups could be combined with sociological theory about social positions as that is one way to understand the outsider-within position that these doctors (and presumably other skilled migrants) have to cope with.
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Family boundary diffusion, individuation, and adjustment among young adults: an investigation of gender and family structure effectsPerrin, Marei Bindi 14 July 2010 (has links)
Drawing on structural family systems theory, this study investigates the relations among family boundary diffusion experienced during adolescence, psychological individuation, and adjustment, from the perspective of older adolescents and young adults. Previous research suggests that boundary diffusion, such as triangulation and parentification, are linked to a variety of negative outcomes for adolescents and young adults (e.g., Buchanan et al., 1991; Hetherington, 1999; Jacobvitz & Bush, 1996), although not uniformly so (e.g., Arditti, 1999; Rosenberg & Guttmann, 2001). Theorists have argued that diffuse family boundaries may hinder the psychological individuation process (Jurkovic, 1997; Lopez, Campbell, & Watkins, 1989), which in turn may be related to low psychological well-being among young adults (Lapsley, Rice, & Shadid, 1989; Mattanah et al., 2004). However, the consequences of some types of boundary diffusion, in particular parentification, may vary depending on the contextual fabric in which they occur (Jurkovic, 1997). Hence, this study explores the extent to which family structure (young adults with married parents versus young adults with divorced, single parents) and gender may impact the relationships among boundary diffusion, individuation, and adjustment. Four-hundred-and-four older adolescents and young adults drawn from the community and a university setting participated in the study. Roughly equal numbers of men and women from both married and divorced family backgrounds were recruited. Participants were asked to reflect back to their adolescence (ages 14 to 17) and completed questionnaires assessing triangulation and parentification experienced by mothers and fathers during this time period. Current psychological individuation from mothers and fathers as well as current general and relationship-specific adjustment were also assessed via self-report measures. As expected, results indicated that participants with divorced parents experienced more boundary diffusion than participants with married parents. Overall, boundary diffusion was reliably associated with poorer adjustment and less psychological individuation irrespective of gender and family structure. Within this general pattern of findings, one notable exception existed: parentification by the same-sex parent among participants with divorced parents appeared not to be related to adjustment, which stood in contrast to findings for participants with married parents. Triangulation, on the other hand, emerged as a consistent and reliable predictor of psychological individuation and adjustment irrespective of family structure and gender. Lastly, as hypothesized, psychological individuation fully mediated the relationship between boundary diffusion and adjustment for the overall sample. This model was also fully supported for women and partially supported for men. Intervention implications arising from this research, including the importance of addressing triangulation dynamics in families and the potential fruitfulness of attending to individuation themes for young adults with histories of boundary diffusion, are highlighted.
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