Nesta dissertação, estuda-se estrelas compactas constituídas por uma forma estável do plasma ultra-relativístico de {\\it quarks} e glúons, a {\\it strange quark matter} ou matéria estranha, com pequena fração de elétrons para manter a neutralidade de carga. São abordadas, aqui, soluções matemáticas razoáveis que descrevem com simplicidade e agilidade certas propriedade dessas estrelas, a começar pela importantíssima relação massa-raio. Um perfil gaussiano para a densidade de energia foi escolhido como ponto de partida para contruir uma solução matemática para o problema e são apresentadas as motivações para tal escolha. Prova-se que o perfil escolhido não soluciona as Equações de Einstein exatamente e uma solução aproximada é fornecida. A seguir, as conhecidas soluções Tolman IV e Buchdahl I foram utilizadas para modelar uma estrela estranha com base no estudo de Alcock, Farhi e Olinto. Discute-se, ainda, como foi redescoberta a solução exata de Finch e Skea e discute-se, também, a solução exata para uma estrela de {\\it quarks} de Komathiraj e Maharaj, construída para um problema ligeiramente diferente, que incluía a existência de um campo elétrico. Conclui-se o trabalho comparando os resultados numéricos de Alcock, Farhi e Olinto com a solução aproximada aqui desenvolvida, apresentando o intervalo de validade desta solução. Além disso, são feitas comparações entre as diferentes soluções exatas e as características que cada uma delas exibe, e discute-se qual delas deve-se utilizar, tendo em mente que característica da estrela estranha se quer estudar. Os caminhos existentes para solucionar as Equações de Einstein, quando se quer modelar um objeto compacto, são discutidos e apontam-se quais os problemas que alguém encontrará ao seguir cada caminho. Por fim, relaciona-se a construção da relação massa-raio com a diferenciação dos tipos de objetos compactos que podem, em princípio, existir. / In this dissertation we study compact stars constituted by a stable form of ultra-relativistic quark-gluon plasma, the strange matter, with a small fraction of electrons to keep the neutrality of charge. We address here reasonable mathematical solutions that describe with simplicity and agility some properties of these stars, beginning by the important mass-radius relationship. A gaussian energy density profile was chosen as the starting point for the construction of a mathematical solution for this problem and the motivations for this choice was presented. We prove that this profile is not an exact solution for the Einstein Field Equations and an approximated solution is presented. Following, the previous known solutions of Tolman IV and Buchdahl I were used to model a strange star, based on the work of Alcock, Farhi and Olinto. We discuss the rediscovery of the exact solution of Finch and Skea and also the exact solution for a quark star by Komathiraj and Maharaj, constructed to a problem slightly different, that includes the existence of an electric field. We conclude this work comparing the numerical results of Alcock, Farhi and Olinto with the approximated solution here developed, presenting the range of validity of this solution. Furthermore, comparisons were made between the different exact solutions and the features displayed by each one and we discuss which solution must be used when one have in mind which features of the strange star one wants to study. The existent ways for solving the Einstein Equations when we want to model a compact star are discussed and we point out the problems that one will find in following each way. At last, we make a relation between the mass-radius relationship and the differentiation of the many types of compact objects that could, in principle, exist.

Com o crescimento do volume de dados manipulado por aplicações de data warehousing, soluções centralizadas tornam-se muito custosas e enfrentam dificuldades para tratar a escalabilidade do volume de dados. Nesse sentido, existe a necessidade tanto de se armazenar grandes volumes de dados quanto de se realizar consultas analíticas (ou seja, consultas OLAP) sobre esses dados volumosos de forma eficiente. Isso pode ser facilitado por cenários caracterizados pelo uso de bancos de dados NoSQL gerenciados em ambientes paralelos e distribuídos. Dentre os desafios relacionados a esses cenários, destaca-se a necessidade de se promover uma análise de desempenho de aplicações de data warehousing que armazenam os dados do data warehouse (DW) em bancos de dados NoSQL orientados a colunas. A análise experimental e padronizada de diferentes sistemas é realizada por meio de ferramentas denominadas benchmarks. Entretanto, benchmarks para DW foram desenvolvidos majoritariamente para bancos de dados relacionais e ambientes centralizados. Nesta pesquisa de mestrado são investigadas formas de se estender o Star Schema Benchmark (SSB), um benchmark de DW centralizado, para o banco de dados NoSQL distribuído e orientado a colunas HBase. São realizadas propostas e análises principalmente baseadas em testes de desempenho experimentais considerando cada uma das quatro etapas de um benchmark, ou seja, esquema e carga de trabalho, geração de dados, parâmetros e métricas, e validação. Os principais resultados obtidos pelo desenvolvimento do trabalho são: (i) proposta do esquema FactDate, o qual otimiza consultas que acessam poucas dimensões do DW; (ii) investigação da aplicabilidade de diferentes esquemas a cenários empresariais distintos; (iii) proposta de duas consultas adicionais à carga de trabalho do SSB; (iv) análise da distribuição dos dados gerados pelo SSB, verificando se os dados agregados pelas consultas OLAP estão balanceados entre os nós de um cluster; (v) investigação da influência de três importantes parâmetros do framework Hadoop MapReduce no processamento de consultas OLAP; (vi) avaliação da relação entre o desempenho de consultas OLAP e a quantidade de nós que compõem um cluster; e (vii) proposta do uso de visões materializadas hierárquicas, por meio do framework Spark, para otimizar o desempenho no processamento de consultas OLAP consecutivas que requerem a análise de dados em níveis progressivamente mais ou menos detalhados. Os resultados obtidos representam descobertas importantes que visam possibilitar a proposta futura de um benchmark para DWs armazenados em bancos de dados NoSQL dentro de ambientes paralelos e distribuídos. / Due to the explosive increase in data volume, centralized data warehousing applications become very costly and are facing several problems to deal with data scalability. This is related to the fact that these applications need to store huge volumes of data and to perform analytical queries (i.e., OLAP queries) against these voluminous data efficiently. One solution is to employ scenarios characterized by the use of NoSQL databases managed in parallel and distributed environments. Among the challenges related to these scenarios, there is a need to investigate the performance of data warehousing applications that store the data warehouse (DW) in column-oriented NoSQL databases. In this context, benchmarks are widely used to perform standard and experimental analysis of distinct systems. However, most of the benchmarks for DW focus on relational database systems and centralized environments. In this masters research, we investigate how to extend the Star Schema Benchmark (SSB), which was proposed for centralized DWs, to the distributed and column-oriented NoSQL database HBase. We introduce proposals and analysis mainly based on experimental performance tests considering each one of the four steps of a benchmark, i.e. schema and workload, data generation, parameters and metrics, and validation. The main results described in this masters research are described as follows: (i) proposal of the FactDate schema, which optimizes queries that access few dimensions of the DW; (ii) investigation of the applicability of different schemas for different business scenarios; (iii) proposal of two additional queries to the SSB workload; (iv) analysis of the data distribution generated by the SSB, verifying if the data aggregated by OLAP queries are balanced between the nodes of a cluster; (v) investigation of the influence caused by three important parameters of the Hadoop MapReduce framework in the OLAP query processing; (vi) evaluation of the relationship between the OLAP query performance and the number of nodes of a cluster; and (vii) employment of hierarchical materialized views using the Spark framework to optimize the processing performance of consecutive OLAP queries that require progressively more or less aggregated data. These results represent important findings that enable the future proposal of a benchmark for DWs stored in NoSQL databases and managed in parallel and distributed environments.

O objetivo desta dissertação é analisar a cobertura jornalística ao cinema brasileiro durante os anos cinqüenta em duas revistas de fãs: A Cena Muda (1921-1955) e Cinelândia (1952-1967), avaliando a estrutura da crítica cinematográfica e seu papel como geradora do star system brasileiro. A análise do material de nosso estudo congrega os anos de 1952 a 1955, único período em que as duas publicações coexistiram. Através da análise comparativa com a cobertura ao cinema de Hollywood, traçamos os paralelos da configuração do estrelismo brasileiro, com especial atenção às estratégias de legitimação do sistema para aumentar o interesse dos leitores e às peculiaridades da crítica em lidar com o star system. / This dissertation has by finality the study of the journalistic coverage to the brazilian cinema during the fifties in two fan magazines: A Cena Muda (1921-1955) and Cinelândia (1952-1967) to assess the structure of the critic cinematograph and their role as producer of brazilian star system. The material analysis of our study assembles the years of 1952 to 1955, only period in which both publications coexisted. Through the comparative analysis with the coverage of the Hollywood cinema, we draw the parallel with the configurations of brazilian star system, with special interest to the system legitimacy strategies to increase the readers interest and to the peculiarities of the critic to handle with the star system.

Spatially-resolved studies of nearby star-forming galaxies are essential to understand various physical and chemical phenomena at play in the interstellar medium in the galaxies, and consequently to obtain a comprehensive picture of galaxy formation and evolution. In this thesis, I perform spatially-resolved analyses of chemical abundances and star-formation in nearby star-forming galaxies - blue compact dwarf galaxies (BCDs) and spiral galaxies. I map various properties of H II regions and the surrounding gas within three BCDs, using integral field spectroscopic (IFS) data from the Gemini Multi-Object Spectrograph-North. While answering questions related to chemical homogeneity, ionisation mechanisms and stellar populations within BCDs, I address more profound issues, which go beyond the characterisation of studied BCDs and aim to explain global phenomena with broader implications. The BCD NGC 4449 hosts a metal-poor central star-forming region, which I explain by various scenarios related to the interplay between star-formation, metal-distribution and gas dynamics within galaxies. The BCD NGC 4670 shows an unusual negative relationship between the nitrogen-to-oxygen ratio and oxygen abundance at spatially-resolved scales. I explore this relation with chemical evolution models and by comparison to other star-forming galaxies and suggest that nitrogen enrichment, variations in star-formation efficiency or hydrodynamical effects may be responsible for the observed relation. For another BCD, SBS 1415+437, the spatially-resolved abundances on average agree with the integrated abundance, implying that low-redshift spatially-resolved results may be directly compared with unresolved high-redshift results. I study spiral galaxies to address long-standing issues related to the reliability of metallicity calibrators and the Schmidt Law of star-formation. Using IFS data of twenty-four spiral galaxies taken with the Multi-Unit Spectroscopic Explorer, I find that the current strong-line metallicity calibrators for H II regions are unsuitable for regions dominated by diffuse ionised gas (DIG). I devise new recipes for estimating the metal-content of the DIG. For another set of nine spiral galaxies, I use multi-wavelength data to show that the spatially-resolved Schmidt relation is very sensitive to the consideration of diffuse background, which is a component unrelated to the current star-formation. Removal of this component from the SFR tracers and the atomic gas results in similar local and global Schmidt relation. To conclude, the spatially-resolved analyses presented in this thesis have led to discoveries and further questions, which I will address in my ongoing and future works.

<p> Stars are born in turbulent molecular clouds that fragment and collapse under the influence of their own gravity, forming a cluster of hundred or more stars. The star formation process is controlled by the interplay between supersonic turbulence and gravity. In this work, the properties of stellar clusters created by numerical simulations of gravoturbulent fragmentation are compared to those from observations. This includes the analysis of properties of individual protostars as well as statistical properties of the entire cluster. </p> <p> It is demonstrated that protostellar mass accretion is a highly dynamical and time-variant process. The peak accretion rate is reached shortly after the formation of the protostellar core. It is about one order of magnitude higher than the constant accretion rate predicted by the collapse of a classical singular isothermal sphere, in agreement with the observations. </p> <p> For a more reasonable comparison, the model accretion rates are converted to the observables bolometric temperature, bolometric luminosity, and envelope mass. The accretion rates from the simulations are used as input for an evolutionary scheme. The resulting distribution in the T_bol-L_bol-M_env parameter space is then compared to observational data by means of a 3D Kolmogorov-Smirnov test. The highest probability found that the distributions of model tracks and observational data points are drawn from the same population is 70%. </p> <p> The ratios of objects belonging to different evolutionary classes in observed star-forming clusters are compared to the temporal evolution of the gravoturbulent models in order to estimate the evolutionary stage of a cluster. While it is difficult to estimate absolute ages, the realtive numbers of young stars reveal the evolutionary status of a cluster with respect to other clusters. The sequence shows Serpens as the youngest and IC 348 as the most evolved of the investigated clusters. </p> <p> Finally the structures of young star clusters are investigated by applying different statistical methods like the normalised mean correlation length and the minimum spanning tree technique and by a newly defined measure for the cluster elongation. The clustering parameters of the model clusters correspond in many cases well to those from observed ones. The temporal evolution of the clustering parameters shows that the star cluster builds up from several subclusters and evolves to a more centrally concentrated cluster, while the cluster expands slower than new stars are formed. </p> / <p>Sterne entstehen im Inneren von turbulenten Molekülwolken, die unter dem Einfluss ihrer eigenen Gravitation fragmentieren und kollabieren. So entsteht ein Sternhaufen aus hundert oder mehr Objekten. Der Sternentstehungsprozess wird durch das Wechselspiel von Überschallturbulenz und Gravitation reguliert. In dieser Arbeit werden verschiedene Eigenschaften solcher Sternhaufen, die mit Hilfe von numerischen Simulationen modelliert wurden, untersucht und mit Beobachtungsdaten verglichen. Dabei handelt es sich sowohl um Eigenschaften einzelner Protosterne, als auch um statistische Parameter des Sternhaufens als Ganzes.</p> <p>Es wird gezeigt, dass die Massenakkretion von Protosternen ein höchst dynamischer und zeitabhängiger Prozess ist. Die maximale Akkretionsrate wird kurz nach der Bildung des Protosterns erreicht, bevor sie annähernd exponentiell abfällt. Sie ist, in Übereinstimmung mit Beobachtungen, etwa um eine Größenordnung höher als die konstante Rate in den klassischen Modellen.</p> <p>Um die Akkretionsraten der Modelle zuverlässiger vergleichen zu können, werden sie mit Hilfe eines Evolutionsschemas in besser beobachtbare Parameter wie bolometrische Temperatur und Leuchtkraft sowie Hüllenmasse umgewandelt. Die dreidimensionale Verteilung dieser Parameter wird anschließend mittels eines Kolmogorov-Smirnov-Tests mit Beobachtungsdaten verglichen.</p> <p>Die relative Anzahl junger Sterne in verschiedenen Entwicklungsstadien wird mit der zeitlichen Entwicklung der Modelle verglichen, um so den Entwicklungsstand des Sternhaufens abschätzen zu können. Während eine genaue Altersbestimmung schwierig ist, kann der Entwicklungsstand eines Haufens relativ zu anderen gut ermittelt werden. Von den untersuchten Objekten stellt sich Serpens als der jüngste und IC 348 als der am weitesten entwickelte Sternhaufen heraus.</p> <p>Zuletzt werden die Strukturen von jungen Sternhaufen an Hand verschiedener statistischer Methoden und eines neuen Maßes für die Elongation eines Haufens untersucht. Auch hier zeigen die Parameter der Modelle eine gute Übereinstimmung mit solchen von beobachteten Objekten, insbesondere, wenn beide eine ähnliche Elongation aufweisen. Die zeitliche Entwicklung der Parameter zeigt, dass sich ein Sternhaufen aus mehreren kleineren Gruppen bildet, die zusammenwachsen und einen zum Zentrum hin konzentrierten Haufen bilden. Dabei werden neue Sterne schneller gebildet als sich der Sternhaufen ausdehnt.</p>

Denna uppsats undersöker TV-serien Star Treks värderingar ur ett politiskt ideologiskt perspektiv. Star Trek är en amerikansk science fiction-serie som skapades av Gene Roddenberry i mitten av 1960-talet. Frågeställningarna behandlar om det finns politiskt relaterade värderingar framställda i Star Trek, vilken politisk ideologi som mest liknar värderingarna i serien, och om det går att tolka det som om Star Trek har en ideologisk värdegrund. Med hjälp av dagordningsteori, kritisk medieteori och teorier om budskap diskuteras TV-bolagens makt över seriens innehåll. De politiska ideologierna konservatism, liberalism och socialism har valts för att kunna jämföras med analysmaterialet. Sex avsnitt från originalserien analyserades med hjälp av en hermeneutik och kvalitativ metod för att bäst kunna få insikt i materialet. Den faktiska analysen har skett med den narratologiska aktantmodellen samt närläsning baserad på kritisk medieteori, där citat bryts ut och tolkas. Resultaten har delats in i tre kategorier, nämligen ekonomi, människosyn och samhällsstruktur för att underlätta sammanställandet. Undersökningen visar att det finns både positivt och negativt framställda värderingar i Star Trek.Ingen politisk ideologi framställs som denenda rätta, men tendensen är att konservatism är minst propagerat för, medan den demokratiska varianten av socialism verkar förespråkas mest. Att resultatet blev splittrat kan härledas till att medieföretagen har stort inflytande över innehållet och att det är svårt att konsekvent framhäva en politisk ideologi i en TV-serie som Star Trek. Detta till följd av formatet på serierna och att de amerikanska TV-bolagen sätter speciella kommersiella krav på produktionen. Det reflekteras också över att politiska värderingar i ett underhållningmedium kan vara effektiva eftersom de politiska budskapen inte har fokus utan intas indirekt. / This thesis examines the values in the TV-series called Star Trek from a political perspective. Star Trek is an American science fiction-series that was created byGene Roddenberry during the mid-1960s. The queries are about whether or not political values are expressed in Star Trek, what political ideology is coherent with those, and if it is possible to interpret this as if Star Trek has an actual politically ideological fundament. Media power over content has been discussed, and because of this there has been made use of critical media theories together with theory of agenda setting and message. The political ideologies of conservatism, liberalism and socialism have been chosen to be compared with the material of analysis.Seven episodes of the original series have been chosen to get a good view of the material by the use of hermeneutic and qualitative research methodology.The analysis was done with the narratological actant model plus a method based on critical media theory, where quotes are being extracted and interpreted. The results have been categorised as either relating to economics, view of mankind or structure of society. The examination shows that there are both positively and negatively described values in Star Trek. No distinct political ideology is being clearly advocated, but there are tendencies for negative views of conservative values aswell as a positive coherence with democratic socialism. The results were difficult to conclude, and this could point towards that the media companies have big influence over their transmitted contents, and that it is difficult to consistently highlight politically ideological values in a television series like Star Trek. This is because the format of TV-series set by american commercial interests puts certain demands on productions. There are reflections about that political values in a medium of entertainment could be effective since the political messages are not in focus but received indirectly.

Re-commissioning, retro-commissioning, Continuous Commissioning® (CC®) are examples of successful systematic processes implemented in buildings to reduce overall building energy consumption, and improve efficiency of systems and their operations and control. The impact of the Continuous Commissioning® Process on the Energy Star® Rating (ESR) of office buildings and hospitals is examined in this thesis. The improvement in performance of a building, and subsequently its ESR, is found to be influenced by its initial ESR, while its location has no impact on improvement. The improvement in ESR is observed to be almost linearly proportional to the percentage of energy saved. For 10% - 20% reductions in energy use typical of the CC® process, the ESR is increased by 10-19 ESR ranks for office buildings and by 13 - 26 ESR ranks for hospitals. The CC® process is found to potentially enable an office building of average initial ESR of 62 and a hospital of average initial ESR of 55, located anywhere in the US, to be eligible to achieve ESR of 75 and consequently the Energy Star recognition. The improvement of ESR is a function of the initial ESR and the building type; hence it is observed to be different for hospitals and office buildings in the study. For hospital and office building models occupying 100,000 ft² of floor area each, a difference of about 30% in the ESR improvement (greater for hospitals) is observed. The energy intensities may be different for buildings with same ESRs that have different location and/or type. An averaged maximum difference of energy intensity of approximately 10% is observed to exist for identical buildings and of the same type but located at different locations. Hospitals are observed to be more than twice as energy intensive as office buildings for the same location and equal ESRs. ESR plotted against % energy savings at site reveals the stepped nature of ESR system. At specific initial ESR and corresponding % savings a reduction of up to approximately 1% for office buildings and up to 1.5% for hospitals does not change the respective ESRs for the model set of buildings in the study.

In this thesis, we study relationships between linear star number and star number and obtain bounds on the linear star number. We obtain an upper bound on linear star number in term of star number：s*(G) ≦ 3s(G). When we forbid certain induced subgraphs, we obtain an upper bound on linear star number. If G is a graph without induced K4－e., we prove that s*(G) ≦ s(G)+1. And, the linear star number of the triangle-free graph is also bounded by s(G)+1. The linear star number and star number are equal when G is a graph with △(G)=3. When G is a graph with △(G)=4, we also obtain s*(G)≦s(G)+1.

Zugl.: Berlin, Humboldt-Univ., Diss.

Made available in DSpace on 2016-06-02T20:23:14Z (GMT). No. of bitstreams: 1 5087.pdf: 3337839 bytes, checksum: dd1a3d8080f9c50c9ec2f2dbd7f23682 (MD5) Previous issue date: 2012-11-30 / Financiadora de Estudos e Projetos / The major media conglomerates consolidated from the 1980s invest heavily on franchises captained by blockbusters movies and a wide range of products derived from them, in search of larger profits in the worldwide entertainment market. This study aims to analyze the marketing characteristics of franchises produced by major media conglomerates. In intend to do so, notes and appointments are made on the Star Wars film franchise, referred to as a kind of genesis for the franchise business model that the entertainment industry practices today. Star Wars created a paradigm in the production process of the Hollywood studios, combining filmic creativity with product marketing practices for disclosure and especially the development of strategic marketing licensing and merchandising of products that carry its brand. Through the analysis of the narrative structure of the Star Wars movies, creative tools used in the development of the story and its characters are identified showing possible paths for creating extensions and sequences that allow the expansion of several derived products across multiple platforms, building the media franchise. / Os grandes conglomerados de mídia, consolidados a partir da década de 1980, investem pesadamente em franquias capitaneadas por filmes blockbusters e uma vasta gama de produtos deles derivados, na busca de lucros cada vez maiores no mercado do entretenimento mundial. Este trabalho tem por objetivo analisar as características mercadológicas das franquias produzidas pelos grandes conglomerados de mídia, tendo como objeto de estudo e apontamentos a franquia cinematográfica Star Wars, referenciada como uma espécie de gênese para o modelo de negócio de franquias que a indústria do entretenimento pratica hoje. Star Wars criou um paradigma no processo produtivo dos estúdios de Hollywood, unindo a criatividade do produto fílmico com as práticas de marketing para sua divulgação e, principalmente, o desenvolvimento de estratégicas mercadológicas de licenciamento e de merchandising dos produtos que levam sua marca. Por meio da análise da estrutura narrativa dos filmes de Star Wars, são identificadas ferramentas que, utilizadas no desenvolvimento da história e de seus personagens, possibilitam caminhos para a criação de extensões e sequências na expansão dos vários produtos derivados, em diversas plataformas, na construção da franquia de mídia.