Gender differences on Scholastic Aptitude Test (SAT) scores were analyzed by racial and socioeconomic groupings. Differences in SAT-Math scores, in SAT-Verbal scores, and in the difference between SAT-Math and SAT-Verbal scores were studied using four racial groupings (African American, Asian American, Caucasian American, and Hispanic American) and two socioeconomic groupings (average-to-high income and average-low income) of students. All differences were tested at the .05 level. Socioeconomic status was determined by using federal guidelines for free and reduced school lunches.The population of the study consisted of 7625 students (3962 females and 3663 males) from two school districts. School District A provided the SAT-M and SAT-V scores of 767 African American, 111 Asian American, 5202 Caucasian American, and 101 Hispanic American students. School District B provided the SAT-M and SAT-V scores of 139 African American,'179 Asian American, and 1126 Caucasian American students.Males, as a group, were found to be significantly higher than females in SAT-M scores and in the difference between SAT-M and SAT-V scores. Asian Americans and Caucasian Americans were found to score significantly higher than both African Americans and Hispanic Americans in SAT-M and SAT-V scores. Asian Americans were found to score significantly higher than all other racial groups in the difference between SAT-M and SAT-V scores. Hispanic Americans were found to score significantly lower than Asian Americans and Caucasian Americans and significantly higher than African Americans in SAT-M and SAT-V scores. African Americans were found to. score significantly lower than all other racial groups in SAT-M and SAT-V scores. A significant two-way interaction was found for gender and race in SAT-M scores, in SAT-V scores, and in the difference between SAT-M and. SAT-V scores. Gender differences in SAT scores varied significantly between each racial grouping.Average-to-high socioeconomic groups were found to have significantly higher scores than average-to-low socioeconomic groups in both SAT-M and SAT-V scores. These differences occurred regardless of gender and race. Significant linear differences were also found to occur in the difference between SAT-M and SAT-V scores over a seven year period. / Department of Educational Leadership

Survey propagation (SP) has recently been discovered as an efficient algorithm in solving classes of hard constraint-satisfaction problems (CSP). Powerful as it is, SP is still a heuristic algorithm, and further understanding its algorithmic nature, improving its effectiveness and extending its applicability are highly desirable. Prior to the work in this thesis, Maneva et al. introduced a Markov Random Field (MRF) formalism for k-SAT problems, on which SP may be viewed as a special case of the well-known belief propagation (BP) algorithm. This result had sometimes been interpreted to an understanding that “SP is BP” and allows a rigorous extension of SP to a “weighted” version, or a family of algorithms, for k-SAT problems. SP has also been generalized, in a non-weighted fashion, for solving non-binary CSPs. Such generalization is however presented using statistical physics language and somewhat difficult to access by more general audience. This thesis generalizes SP both in terms of its applicability to non-binary problems and in terms of introducing “weights” and extending SP to a family of algorithms. Under a generic formulation of CSPs, we first present an understanding of non-weighted SP for arbitrary CSPs in terms of “probabilistic token passing” (PTP). We then show that this probabilistic interpretation of non-weighted SP makes it naturally generalizable to a weighted version, which we call weighted PTP. Another main contribution of this thesis is a disproof of the folk belief that “SP is BP”. We show that the fact that SP is a special case of BP for k-SAT problems is rather incidental. For more general CSPs, SP and generalized SP do not reduce from BP. We also established the conditions under which generalized SP may reduce as special cases of BP. To explore the benefit of generalizing SP to a wide family and for arbitrary, particularly non-binary, problems, we devised a simple weighted PTP based algorithm for solving 3-COL problems. Experimental results, compared against an existing non-weighted SP based algorithm, reveal the potential performance gain that generalized SP may bring.

Conformant planning is the problem of finding a sequence of actions for achieving a goal in the presence of uncertainty in the initial state and state transitions. While few practical problems are purely conformant, the ability to find conformant plans is needed in planning with observations where conformant situations are an special case and where relaxations into conformant planning yield useful heuristics. In this dissertation, we introduce new formulations for tackling the conformant planning problem with deterministic actions using translations. On the one hand, we propose a translation in propositional logic and two schemes for obtaning conformant plans for it, one based on boolean operations of projection and model counting, the other based on projection and satisfiability. On the other hand, we introduce translations of the conformant planning problem into classical problems that are solved by a modern and effective classical planner. We analyze the formal properties of the translations into classical planning and evaluate the performance of the resulting conformant planners. / La planificación conformante es el problema de encontrar una secuencia de acciones para lograr un objetivo en presencia de información incompleta sobre el estado inicial y en las transiciones entre estados. Aunque pocos problemas son de carácter puramente conformante, la posibilidad de encontrar planes conformantes es necesaria en planificación con observaciones, donde las situaciones conformantes son un caso particular, y donde las relajaciones a planificación conformante dan heurísticas útiles. En esta tesis atacamos el problema de la planificación conformante con acciones determinísticas mediante dos formulaciones basadas en traducciones. Por un lado, proponemos una traducción a lógica proposicional y dos esquemas para obtener planes conformantes a partir de ésta, uno basado en operaciones booleanas de projección y conteo de modelos, y otro basado en projección y satisfacción proposicional. Por otro lado, introducimos traducciones que permiten transformar un problema de planificación conformante en un problema de planificación clásica que es luego resuelto usando planificadores clásicos. También analizamos las propiedades formales de las traducciones y evaluamos el rendimiento de los planificadores obtenidos.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-09-05T19:39:01Z No. of bitstreams: 1 IvaniseBorgesSouza_DISSERT.pdf: 2800497 bytes, checksum: 50c24b5e23510fcd8e07cecda4fbee7c (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-09-15T20:52:51Z (GMT) No. of bitstreams: 1 IvaniseBorgesSouza_DISSERT.pdf: 2800497 bytes, checksum: 50c24b5e23510fcd8e07cecda4fbee7c (MD5) / Made available in DSpace on 2017-09-15T20:52:51Z (GMT). No. of bitstreams: 1 IvaniseBorgesSouza_DISSERT.pdf: 2800497 bytes, checksum: 50c24b5e23510fcd8e07cecda4fbee7c (MD5) Previous issue date: 2016-08-10 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A atividade tur?stica brasileira, ao longo dos ?ltimos anos, vem se desenvolvendo substancialmente. Por?m, n?o h? informa??es o bastante para dimensionar o desempenho do turismo na economia, pois as pesquisas que existem n?o s?o suficientes ou est?o com dados defasados. As pesquisas com abordagem estat?stica e econ?mica, como a Conta Sat?lite do Turismo (CST), configuram-se como importantes fontes de informa??es para o planejamento de pol?ticas, investimentos e expans?o do mercado, visando melhorias para a popula??o, para o trade tur?stico e para o turista. Com a mensura??o econ?mica do turismo, torna-se poss?vel identificar atividades em crescimento, que geram postos de trabalho, renda e melhorias da condi??o social da popula??o, assim como apontar atividades estagnadas. O presente trabalho tem por objetivo analisar a participa??o das Atividades Caracter?sticas do Turismo (ACT?s) na economia brasileira no ano de 2013. O intuito ? gerar informa??es para o dimensionamento e o desenvolvimento da atividade tur?stica no contexto brasileiro. A pesquisa caracteriza-se como explorat?rio-descritiva, transversal, de abordagem quantitativa. O estudo foi realizado a partir de dados secund?rios extra?dos principalmente da Pesquisa Anual de Servi?os desenvolvida pelo Instituto Brasileiro de Geografia e Estat?stica ? IBGE e do Sistema de Informa??es Sobre o Mercado de Trabalho no setor de turismo do Instituto de Pesquisa Econ?mica e Aplicada. A metodologia aplicada teve como base o modelo da CST-99 do Brasil e o relat?rio ?Economia do Turismo: uma perspectiva macroecon?mica 2003-2009?, ambas as publica??es fundamentadas nas diretrizes e metodologias recomendadas pela Organiza??o Mundial do Turismo (OMT) e pelo Sistema de Contas Nacionais -1993/2008. Para dimensionar a participa??o das ACT?s na economia, foram aplicados os conceitos das identidades cont?beis sobre os agregados macroecon?micos do turismo. Com isso, o trabalho teve com resultado a estimativa do valor bruto da produ??o, consumo intermedi?rio, valor agregado bruto, gastos com o pessoal, excedente operacional bruto, n?mero de postos de trabalho, rendimentos pagos e n?mero de empresas. Para tanto, esta pesquisa vem a contribuir para a literatura da economia do turismo com perspectiva de ampliar as discuss?es sobre os mecanismos de mensura??o do turismo para gera??o de informa??es econ?micas e estat?sticas para o Brasil. / Brazilian tourism has been developing, quickly over the last years. However, there is not enough information to measure the performance of tourism in the economy, because the existing research sufficiently specific or obsolete data. Statistical and economic research, such as the Tourism Satellite Account (TSA), in an important source of information for policy planning, investment and market expansion, enabling improvements for residents, businesses and tourists. With the economic measurement of tourism, it is possible to identify growing activities that generate jobs, income and welfare, also pointing stable activities. This study aims to analyze the participation of Tourism Characteristic Activities (TCAs) in the Brazilian economy in 2013.The objective is to generate information for the measurement and development of tourism in the Brazilian context. The research is characterized as exploratory, descriptive, cross-sectional, using quantitative approach. The study relied on secondary data sources drawn mainly from research the Annual Survey of Services developed by the Brazilian Institute of Geography and Statistics (IBGE) and the tourism Labor Market Information System of the Applied Economic Research Institute (IPEA). The applied methodology was based on Brazil?s TSA-99 and on the report ?Tourism Economics: a macroeconomic perspective 2003-2009?, both based on the guidelines and methodologies recommended by the World Tourism Organization (UNWTO) and National Accounts System-1993/2008.To measure the participation of TCAs in the economy, the concepts of accounting identities of the macroeconomic aggregates of tourism were applied. Thus, the study resulted in estimation of gross value of production, intermediate consumption, gross value added, expenses personnel, gross operating surplus, number of jobs, paid income and number of companies. Therefore, this research contributes to the tourism literature with perspective to expand discussions on tourism measurement mechanisms for the generation of economic and statistical information about Brazil.

In this paper the rate of convergence, speed of execution and symplectic properties of the time-integrators Leap-Frog (LF2), fourth order Runge-Kutta(RK4) and Crank-Nicholson (CN2) have been studied. This was done by solving the one-dimensional model for a particle in a box (Dirichlet-conditions). The results show that RK4 is the fastest in achieving higher tolerances, while CN2 is the fastest in achieving lower tolerances. Fourth order corrections of LF (LF4)and CN (CN4) were also studied, though these showed no improvements overLF2 and CN2. All methods were shown to exhibit symplectic behavior.

Currently, there is lack of effective and scalable methods to specify and ana-lyze requirements specifications, and verify the behavioral models of embed-ded systems. Most embedded systems requirements are expressed in naturallanguage which is flexible and intuitive but frequently ambiguous, vague andincomprehensive. Besides to natural language, template-based requirementsspecification methods are used to specify requirements specifications (esp. insafety-critical applications), which reduce ambiguity and improves the com-prehensibility of the specifications. However, the template-based method areusually rigid due to the fixed structures of the templates. They also lack meta-models for extensibility, and template selection is challenging.In this thesis, we proposed a domain specific language for embedded sys-tems, called ReSA, which is constrained natural language but flexible enoughto allow engineers to use different constructs to specify requirements. Thelanguage has formal semantics in proportional logic and description logic thatenables non-trivial and rigorous analysis of requirements specification, e.g.,consistency checking, completeness of specifications, etc.Moreover, we propose a scalable formal verification of Simulink models,whichisusedtodescribethebehaviorofsystemsthroughcommunicatingfunc-tional blocks. In industry, Simulink is the de facto modeling and analysis en-vironment of embedded systems. It is also used to generate code automati-cally from special Simulink models for various hardware platforms. However,Simulink lacks formal approach to verify large and hybrid Simulink models.Therefore, we also propose a formal verification of Simulink models, repre-sented as stochastic timed automata, using statistical model checking, whichhas proven to scale for industrial applications.We validate our approaches on industrial use cases from the automotiveindustry. These includes Adjustable Speed Limiter (ASL) and Brake-By-Wire(BBW) systems from Volvo Group Trucks Technology, both safety-critical. / Verispec

Survey propagation (SP) has recently been discovered as an efficient algorithm in solving classes of hard constraint-satisfaction problems (CSP). Powerful as it is, SP is still a heuristic algorithm, and further understanding its algorithmic nature, improving its effectiveness and extending its applicability are highly desirable. Prior to the work in this thesis, Maneva et al. introduced a Markov Random Field (MRF) formalism for k-SAT problems, on which SP may be viewed as a special case of the well-known belief propagation (BP) algorithm. This result had sometimes been interpreted to an understanding that “SP is BP” and allows a rigorous extension of SP to a “weighted” version, or a family of algorithms, for k-SAT problems. SP has also been generalized, in a non-weighted fashion, for solving non-binary CSPs. Such generalization is however presented using statistical physics language and somewhat difficult to access by more general audience. This thesis generalizes SP both in terms of its applicability to non-binary problems and in terms of introducing “weights” and extending SP to a family of algorithms. Under a generic formulation of CSPs, we first present an understanding of non-weighted SP for arbitrary CSPs in terms of “probabilistic token passing” (PTP). We then show that this probabilistic interpretation of non-weighted SP makes it naturally generalizable to a weighted version, which we call weighted PTP. Another main contribution of this thesis is a disproof of the folk belief that “SP is BP”. We show that the fact that SP is a special case of BP for k-SAT problems is rather incidental. For more general CSPs, SP and generalized SP do not reduce from BP. We also established the conditions under which generalized SP may reduce as special cases of BP. To explore the benefit of generalizing SP to a wide family and for arbitrary, particularly non-binary, problems, we devised a simple weighted PTP based algorithm for solving 3-COL problems. Experimental results, compared against an existing non-weighted SP based algorithm, reveal the potential performance gain that generalized SP may bring.

Les aciers ODS (Oxide Dispersed Strengthened Steels), renforcés par des dispersions de nano-oxydes métalliques (à base d'éléments Y, Ti et O), sont des matériaux prometteurs pour les réacteurs nucléaires de génération IV. La compréhension fine des mécanismes mis en jeu lors de la précipitation de ces nano-oxydes permettrait d'améliorer la fabrication et les propriétés mécaniques de ces aciers ODS, avec un fort impact économique en vue de leur industrialisation. Pour étudier expérimentalement ces mécanismes, une approche analytique par implantation ionique est utilisée dans cette étude, permettant de contrôler différents paramètres de synthèse de ces précipités comme la température et leur concentration. Ce projet a permis de démontrer la faisabilité de cette méthode et d'étudier le comportement d'alliages modèles (à base d'oxyde d'aluminium) sous recuit thermique. Des alliages Fe-10Cr de haute pureté ont été implantés avec des ions Al et O à température ambiante. Les observations de microscopie électronique en transmission ont montré que des nano-oxydes apparaissent dans la matrice de Fe-10Cr dès l'implantation à température ambiante, sans recuit subséquent. Les défauts créés lors de l'implantation ionique sont à l'origine de la mobilité des éléments introduits, permettant la nucléation de ces nanoparticules, de quelques nm de diamètre. Ces nanoparticules sont composées d'aluminium et d'oxygène, et également de chrome. Les examens en haute résolution montrent que leur structure cristallographique correspond à celle d'un composé hors équilibre de l'oxyde d'aluminium (de type γ-Al₂O₃). Les traitements thermiques effectués après implantation induisent une croissance de la taille de ces nano-oxydes, et un changement de phase qui tend vers la structure d'équilibre (de type α-Al₂O₃). Ces résultats sur des alliages modèles s'appliquent entièrement aux matériaux industriels : en effet l'implantation ionique reproduit les conditions du broyage, et les traitements thermiques sont à des températures équivalentes à celles des traitements d'élaboration thermo-mécaniques. Un mécanisme de la précipitation de nano-oxydes dispersés dans des alliages ODS est proposé dans ce manuscrit. / ODS (Oxide Dispersed Strengthened) steels, which are reinforced with metal dispersions of nano-oxides (based on Y, Ti and O elements), are promising materials for future nuclear reactors. The detailed understanding of the mechanisms involved in the precipitation of these nano-oxides would improve manufacturing and mechanical properties of these ODS steels, with a strong economic impact for their industrialization. To experimentally study these mechanisms, an analytical approach by ion implantation is used, to control various parameters of synthesis of these precipitates as the temperature and concentration. This study demonstrated the feasibility of this method and concerned the behaviour of alloys models (based on aluminium oxide) under thermal annealing. High purity Fe-10Cr alloys were implanted with Al and O ions at room temperature. Transmission electron microscopy observations showed that the nano-oxides appear in the Fe-10Cr matrix upon ion implantation at room temperature without subsequent annealing. The mobility of implanted elements is caused by the defects created during ion implantation, allowing the nucleation of these nanoparticles, of a few nm in diameter. These nanoparticles are composed of aluminium and oxygen, and also chromium. The high-resolution experiments show that their crystallographic structure is that of a non-equilibrium compound of aluminium oxide (cubic γ-Al₂O₃ type). The heat treatment performed after implantation induces the growth of the nano-sized oxides, and a phase change that tends to balance to the equilibrium structure (hexagonal α-Al₂O₃ type). These results on model alloys are fully applicable to industrial materials: indeed ion implantation reproduces the conditions of milling and heat treatments are at equivalent temperatures to those of thermo-mechanical treatments. A mechanism involving the precipitation of nano-oxide dispersed in ODS alloys is proposed in this manuscript based on the obtained experimental results, and the existing literature.

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