Data analysis is the process of inspecting, cleaning, extract, and modeling data with the intention of extracting useful information in order to support users in their decisions. With the advent of Big Data, data analysis was becoming more complicated due to the volume and variety of data. This process begins with the acquisition of the data and the selection of the data that is useful for the desiderata analysis. With such amount of data, also expert users are not able to inspect the data and understand if a dataset is suitable or not for their purposes. In this dissertation, we focus on five problems in the broad data analysis process to help users find insights from the data when they do not have enough knowledge about its data. First, we analyze the data description problem, where the user is looking for a description of the input dataset. We introduce data descriptions: a compact, readable and insightful formula of boolean predicates that represents a set of data records. Finding the best description for a dataset is computationally expensive and task-specific; we, therefore, introduce a set of metrics and heuristics for generating meaningful descriptions at an interactive performance. Secondly, we look at the problem of order dependency discovery, which discovers another kind of metadata that may help the user in the understanding of characteristics of a dataset. Our approach leverages the observation that discovering order dependencies can be guided by the discovery of a more specific form of dependencies called order compatibility dependencies. Thirdly, textual data encodes much hidden information. To allow this data to reach its full potential, there has been an increasing interest in extracting structural information from it. In this regard, we propose a novel approach for extracting events that are based on temporal co-reference among entities. We consider an event to be a set of entities that collectively experience relationships between them in a specific period of time. We developed a distributed strategy that is able to scale with the largest on-line encyclopedia available, Wikipedia. Then, we deal with the evolving nature of the data by focusing on the problem of finding synonymous attributes in evolving Wikipedia Infoboxes. Over time, several attributes have been used to indicate the same characteristic of an entity. This provides several issues when we are trying to analyze the content of different time periods. To solve it, we propose a clustering strategy that combines two contrasting distance metrics. We developed an approximate solution that we assess over 13 years of Wikipedia history by proving its flexibility and accuracy. Finally, we tackle the problem of identifying movements of attributes in evolving datasets. In an evolving environment, entities not only change their characteristics, but they sometimes exchange them over time. We proposed a strategy where we are able to discover those cases, and we also test our strategy on real datasets. We formally present the five problems that we validate both in terms of theoretical results and experimental evaluation, and we demonstrate that the proposed approaches efficiently scale with a large amount of data.

A schema-based instruction allows students to approach a mathematics problem by focusing on the underlying semantic or problem structure, thus facilitating conceptual understanding and adequate skills. The purpose of this study was to examine the effectiveness of schema-based intervention on the mathematical word problem solving skills of middle school students with learning disabilities in grades 6 and 7. A nonconcurrent multiple baseline design was used for the study. Four middle school students with learning disabilities participated in pre-experimental (i.e., introduction, screening test, and Mathematics Interest Inventory sessions) and experimental (i.e., baseline, intervention, post-intervention test with generalization test, and maintenance test) sessions over a 13-week period. Participants were randomly assigned to a priori baseline durations (i.e., 6, 9, 12, 17 days) (Watson & Workman, 1981). During the intervention phase, students received 12 sessions of individual 30-35 minute schema-based intervention for 6 days (i.e., 2 sessions per day). Students participated in guided and independent practice and were encouraged to ask questions as they worked to master the material taught in each intervention session. During the postintervention phase, the four students’ accuracy performance was evaluated by six untimed achievement or generalization tests. The achievement and generalization tests contained a total of 10 one-step multiplication and division word problems. All of the students achieved scores greater than a pre-determined criterion level of 70% accuracy on the six consecutive tests. Two weeks after termination of the post intervention phase, each student’s accuracy performance on the achievement and generalization tests was examined during the follow-up maintenance phase. Findings revealed that the four students’ performance substantially improved after they received the intervention. All four students achieved scores that exceeded the criterion level (70% accuracy) on the achievement tests during the post intervention phase. These findings provide empirical evidence that schema-based intervention is effective in teaching middle school students with learning disabilities to solve multiplication and division word problems. Limitations of the research and implications for practice and future research are discussed. / text

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.

A neotenia é um importante processo biológico-evolutivo que conserva traços fenotípicos do jovem no indivíduo adulto. A neotenia modifica a velocidade típica da ontogênese das características morfológicas compartilhadas pelos ancestrais. Essas mudanças podem representar oportunidades de mudanças fenotípicas dramáticas com poucas alterações genéticas, possibilitando alterações de estados especializados. O etólogo Konrad Lorenz reconheceu características neotênicas em humanos e algumas espécies de mamíferos na fórmula estrutural do corpo (principalmente da face) típica de infantes. Essa fórmula corpórea foi batizada por Lorenz de Kindchenschema. Os humanos típicos respondem quando observam traços infantis ativando uma resposta chamada de Efeito Kindchenschema (EK). Neste efeito verifica-se uma diminuição da agressividade, estimulação do cuidado parental e engajamento social. São raros os trabalhos de escaneamento do olhar em portadores de disfunções do neurodesenvolvimento, como a Síndrome de Williams (SW) e o Transtorno do Espectro Autista (TEA). O presente trabalho é o primeiro na literatura a investigar o escaneamento do olhar em portadores de SW e TEA usando estímulos faciais neotênicos de humanos e animais. Na presente investigação foram estudados 21 portadores de SW e 25 portadores de TEA, o grupo controle (GC) contou com 33 participantes. Encontramos uma correspondência entre os resultados declarados do estímulo preferido e o tempo de fixação. Os resultados mostraram que todos os participantes fixaram mais a região dos olhos de humanos e animais, sendo que o GC fixou mais tempo do que os portadores de SW e TEA. Foi possível separar usando o tempo de fixação nos olhos e HeatMaps os três grupos investigados. É viável a produção de um exame clínico auxiliar rápido e não-invasivo para indivíduos com suspeita de uma disfunção do neurodesenvolvimento. Talvez a região do nariz e boca sejam menos importantes e as orelhas mais importantes do que pensávamos nos estímulos neotênicos. Os estímulos mais neotênicos de infantes humanos e animais produziram um padrão semelhantes do tempo de fixação nos três grupos estudados. Esses resultados demonstram que portadores de SW e TEA respondem positivamente a estímulos faciais neotênicos. Sugerimos que as novas investigações na área incorporem também como variáveis faciais as orelhas, cor do cabelo e olhos, e simetria facial / Neoteny is an important biological-evolutionary process that retains phenotypic traits of the young in the adult individual of a species. Neoteny modifies the typical ontogeny velocity of the morphological characteristics shared with the ancestors. These changes may represent opportunities for dramatic phenotype modifications with few genetic changes, allowing for alterations in specialized states. The ethologist Konrad Lorenz has recognized neotenic characteristics in humans and some species of mammals in the structural formula of the body (mainly of the face) typical of infants. This body formula was named by Lorenz Kindchenschema. Typical humans respond when they observe infant traits by activating a response called the Kindchenschema Effect (KE). In this effect, there is a decrease in aggressiveness, stimulation of parental care and social engagement. There is a paucity of eye scanning in individuals with neurodevelopmental disorders such as Williams Syndrome (WS) and Autistic Spectrum Disorder (ASD). The present work is the first in the literature to investigate the eye scanning in WS and ASD patients using neotenic facial stimuli of humans and animals. In the present investigation, 21 WS and 25 ASD participants were studied. The control group (CG) had 33 participants. We found a correspondence between the stated results of the preferred stimulus and the fixation time. The results showed that all the participants fixed more the region of the eyes of humans and animals, and the CG fixed more time than the WS and ASD participants. It was possible to distinguish, using the fixation time in the eyes and Heat Maps, the three groups. The production of a rapid and non-invasive auxiliary clinical examination is feasible for individuals suspected in presenting a neurodevelopmental dysfunction. Perhaps the nose and mouth areas are less important, and the ears are more important than previously considered with respect. The more neotenic stimuli of human and animal infants produced a similar pattern of fixation time in the three groups studied. This may represent a greater adaptive value than we thought of those with WS and ASD. We suggest that the new investigations can also incorporate facial variables as ears, hair color and eyes, and facial symmetry

In today's networked world, information is widely distributed across many independent databases in heterogeneous formats. Integrating such information is a difficult task and has been adressed by several projects. However, previous integration solutions, such as the EVE-Project, have several shortcomings. Database contents and structure change frequently, and users often have incomplete information about the data content and structure of the databases they use. When information from several such insufficiently described sources is to be extracted and integrated, two problems have to be solved: How can we discover the structure and contents of and interrelationships among unknown databases, and how can we provide durable integration views over several such databases? In this dissertation, we have developed solutions for those key problems in information integration. The first part of the dissertation addresses the fact that knowledge about the interrelationships between databases is essential for any attempt at solving the information integration problem. We are presenting an algorithm called FIND2 based on the clique-finding problem in graphs and k-uniform hypergraphs to discover redundancy relationships between two relations. Furthermore, the algorithm is enhanced by heuristics that significantly reduce the search space when necessary. Extensive experimental studies on the algorithm both with and without heuristics illustrate its effectiveness on a variety of real-world data sets. The second part of the dissertation addresses the durable view problem and presents the first algorithm for incremental view maintenance in schema-restructuring views. Such views are essential for the integration of heterogeneous databases. They are typically defined in schema-restructuring query languages like SchemaSQL, which can transform schema into data and vice versa, making traditional view maintenance based on differential queries impossible. Based on an existing algebra for SchemaSQL, we present an update propagation algorithm that propagates updates along the query algebra tree and prove its correctness. We also propose optimizations on our algorithm and present experimental results showing its benefits over view recomputation.

A neotenia é um importante processo biológico-evolutivo que conserva traços fenotípicos do jovem no indivíduo adulto. A neotenia modifica a velocidade típica da ontogênese das características morfológicas compartilhadas pelos ancestrais. Essas mudanças podem representar oportunidades de mudanças fenotípicas dramáticas com poucas alterações genéticas, possibilitando alterações de estados especializados. O etólogo Konrad Lorenz reconheceu características neotênicas em humanos e algumas espécies de mamíferos na fórmula estrutural do corpo (principalmente da face) típica de infantes. Essa fórmula corpórea foi batizada por Lorenz de Kindchenschema. Os humanos típicos respondem quando observam traços infantis ativando uma resposta chamada de Efeito Kindchenschema (EK). Neste efeito verifica-se uma diminuição da agressividade, estimulação do cuidado parental e engajamento social. São raros os trabalhos de escaneamento do olhar em portadores de disfunções do neurodesenvolvimento, como a Síndrome de Williams (SW) e o Transtorno do Espectro Autista (TEA). O presente trabalho é o primeiro na literatura a investigar o escaneamento do olhar em portadores de SW e TEA usando estímulos faciais neotênicos de humanos e animais. Na presente investigação foram estudados 21 portadores de SW e 25 portadores de TEA, o grupo controle (GC) contou com 33 participantes. Encontramos uma correspondência entre os resultados declarados do estímulo preferido e o tempo de fixação. Os resultados mostraram que todos os participantes fixaram mais a região dos olhos de humanos e animais, sendo que o GC fixou mais tempo do que os portadores de SW e TEA. Foi possível separar usando o tempo de fixação nos olhos e HeatMaps os três grupos investigados. É viável a produção de um exame clínico auxiliar rápido e não-invasivo para indivíduos com suspeita de uma disfunção do neurodesenvolvimento. Talvez a região do nariz e boca sejam menos importantes e as orelhas mais importantes do que pensávamos nos estímulos neotênicos. Os estímulos mais neotênicos de infantes humanos e animais produziram um padrão semelhantes do tempo de fixação nos três grupos estudados. Esses resultados demonstram que portadores de SW e TEA respondem positivamente a estímulos faciais neotênicos. Sugerimos que as novas investigações na área incorporem também como variáveis faciais as orelhas, cor do cabelo e olhos, e simetria facial / Neoteny is an important biological-evolutionary process that retains phenotypic traits of the young in the adult individual of a species. Neoteny modifies the typical ontogeny velocity of the morphological characteristics shared with the ancestors. These changes may represent opportunities for dramatic phenotype modifications with few genetic changes, allowing for alterations in specialized states. The ethologist Konrad Lorenz has recognized neotenic characteristics in humans and some species of mammals in the structural formula of the body (mainly of the face) typical of infants. This body formula was named by Lorenz Kindchenschema. Typical humans respond when they observe infant traits by activating a response called the Kindchenschema Effect (KE). In this effect, there is a decrease in aggressiveness, stimulation of parental care and social engagement. There is a paucity of eye scanning in individuals with neurodevelopmental disorders such as Williams Syndrome (WS) and Autistic Spectrum Disorder (ASD). The present work is the first in the literature to investigate the eye scanning in WS and ASD patients using neotenic facial stimuli of humans and animals. In the present investigation, 21 WS and 25 ASD participants were studied. The control group (CG) had 33 participants. We found a correspondence between the stated results of the preferred stimulus and the fixation time. The results showed that all the participants fixed more the region of the eyes of humans and animals, and the CG fixed more time than the WS and ASD participants. It was possible to distinguish, using the fixation time in the eyes and Heat Maps, the three groups. The production of a rapid and non-invasive auxiliary clinical examination is feasible for individuals suspected in presenting a neurodevelopmental dysfunction. Perhaps the nose and mouth areas are less important, and the ears are more important than previously considered with respect. The more neotenic stimuli of human and animal infants produced a similar pattern of fixation time in the three groups studied. This may represent a greater adaptive value than we thought of those with WS and ASD. We suggest that the new investigations can also incorporate facial variables as ears, hair color and eyes, and facial symmetry

With the increased volume of commercial content online, some news sites have adopted so-called native advertising on their websites to convey marketing messages more discreetly. As an increased share of advertising budgets is spent on this form of advertising this essay aims to examine its news consumer’s attitudes towards the phenomenon. The research was carried out through a qualitative study where news consumers discussed their attitudes in two separate focus groups. This was analyzed with the help of the previous studies Advertisement - an uninvited guest? and Banner Blindness as well as theories including theory of science hermeneutics, reception analysis, convergence culture, brand schema, advertising schema and ad- brand attitude.The results show that in most cases native advertising is met with indifferent attitudes but in some cases also confusion, which could lead to negative attitudes towards the ad and the news site. The respondents mostly had a scientism towards native ads but because they don´t intend to pay for their news their attitudes are more indifferent than negative. However most of the respondents experienced a so called third-person effect which means that they think they’re not affected by ads, but others are. They say that their generation is the hardest group to fool. Thus this thesis concludes that the most favorable ads were technology- and channel driven, which is a form of semi native ads. This is making it a little less native and more recognizable as a commercial message

Företaget Nethouse har haft uppdraget att kravställa, utveckla och implementera ett verksamhetssystem åt Sveriges  Skorstensfejaremästares Riksförbund (SSR). Medlemsföretagen i SSR bedriver sotarverksamhet på uppdrag av Sveriges kommuner och är beroende av insamlad data kopplad till deras verksamhet. I det nyutvecklade systemet, som går under namnet Ritz, samlas informationen i en central databas och är tillgänglig för flertalet intressenter med hjälp av ny teknik och modernare lösningar. Systemet är helt webbaserat och körs som en molntjänst, tillgängligt via antingen en webbsida eller som mobilapplikation. Åtkomsten av data baseras på företagsnivå på ”stämplad” data i databasen och för att reglera åtkomsten för företagsanvändare till respektive företags data används rollbaserad åtkomstkontroll. Detta examensarbete har syftat till att utveckla en prototyp till en beslutsstödslösning för dynamisk åtkomst till de datamängder som lagras inom Ritz. Nethouse har efterfrågat en prototyp för en BI-lösning som visar på möjligheter och fördelar för intressenter till Ritz med att implementera en sådan. Då integration och förvaltning är viktiga faktorer för Nethouse har ett krav på prototypen varit att den utvecklats inom Microsofts programvaror, precis som resten av Ritz. Prototypen färdigställdes genom konstruerandet av ett centralt data warehouse enligt Ralph Kimballs metodologier och genom implementation av en OLAP-kub byggd i Microsoft SSAS. Dataöverföringen från datakällorna till beslutsstödslösningens data warehouse skedde genom utvecklandet av en ETL-process i Microsoft SSIS. Den resulterande kuben har främst utformats för att kunna besvara den sortens frågor som länsstyrelser ställer till sotarföretag i kontrollsyfte och stöder förfrågningar mot de två centrala affärsprocesserna sotning och brandskyddskontroll. Dessa förfrågningar kan filtreras på flertalet dimensioner som exempelvis tid, utförare, status och kontrollutfall. Prototypen begränsar även åtkomst till den information som användare har rätt att ta del av genom att koppla samman användare och objekt till geografiska indelningar som kallas distrikt. Denna dynamiska säkerhetslösning ger goda förutsättningar för att kunna hantera förändringar i användarnas behörighet i framtiden. Genom den utvalda lösningen behålls den dynamiska naturen i systemet, då åtkomst till beslutsstödstjänsten kan fås genom flertalet källor som stödjer uppkoppling mot Microsofts multidimensionella beslutsstödslösningar, bland annat Excel och SQL Server Reporting Services.

La fonction d’anticipation programmant l'action et ses conséquences sur la posture s’appuie sur les représentations sensorimotrice. L’adolescence étant caractérisée par des modifications du corps et du cerveau, cette thése évalue les liens qui unissent anticipation, représentations sensorimotrices et maturation cérébrale. La tâche bimanuelle de délestage met en jeu l’utilisation d’un bras postural, supportant le poids, et d’un bras manipulateur, qui le déleste. Dans cette tâche, l'anticipation s'exprime par les ajustements posturaux anticipés (APA), annulant la déstabilisation posturale causée par l'action. Des enregistrements cinématiques, EMG et EEG ont été utilisés. Bien qu’une stabilisation posturale stable soit reportée, les APAs à l’adolescence se caractérisent par une amélioration de la latence de l’inhibition des fléchisseurs. Chez l’adulte, les APA s’expriment par une désynchronisation du rythme mu et une onde positive au dessus de M1 impliqué dans la posture. Les caractéristiques temporelles de ces signatures varient à l’adolescence. L’apprentissage d’un nouveau contrôle postural est caractérisé par une amélioration rapide puis plus lente de la stabilisation posturale. Plus tardive à l'adolescence, cette acquisition repose sur la maitrise du réglage temporel de l’inhibition des fléchisseurs. Une intégration des retours proprioceptifs issus de l’action permettrait la construction d’une représentation sensorimotrice. Exprimée par la maitrise des paramètres temporels, la réactualisation des représentations sensorimotrice à l’adolescence passerait par une meilleure intégration des retours proprioceptifs. La maturation des régions cérébrales serait aussi capitale. / Voluntary action requires an anticipation, which predicts the consequence of action on posture. Anticipation rests on action and body representations. Adolescence is characterized by body modifications and cerebral maturation. This thesis explored the link between the anticipatory function, action and body representations, and the cerebral maturation. The bimanual load-lifting task engages a postural arm, supporting the load, and a motor arm, lifting the load. In this task, the anticipation, expressed by anticipatory postural adjustments (APA) cancelled the destabilizing effect of movement on the posture. Kinematics, EMG and EEG were recorded. Although performances of postural stabilization were stable, APAs at the adolescence were characterized by an earlier latency of inhibition on the postural flexors. In adults, APA are expressed by a mu rhythm desynchronization and a positive wave over M1involved in posture, which presented different temporal characteristics in adolescents. Thus, the improvement of APA would be underlain by a maturation of these EEG activities. Learning a new postural control was characterized by a rapid followed by a slow improvement of the postural stabilisation. This acquisition rested on the mastering of the temporal parameters of the flexors inhibition, which took more time at the adolescence. Integration of proprioceptive feedback coming from action allowed an update of sensorimotor representation. Expressed by the mastering of the temporal parameters, the update of body and action representations at adolescence would imply an enhancement of the integration of proprioceptive information. Maturation of the cerebral areas would be a key element.

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.