Methods to Build Optimal Database Model

The paper considers the search for optimal database models and effective ways of their building. Traditional data models are considered and their limitations and shortcomings are revealed during implementation in modern information systems. The main points of relational database normalization theory are studied as well as essential requirements to optimal database model are defined.У статті розглядається пошук оптимальних моделей баз даних та ефективних способів їх побудови. Розглядаються традиційні моделі даних, а також виявляються їх обмеження та недоліки при впровадженні в сучасні інформаційні системи. Вивчаються основні моменти теорії нормалізації реляційних баз даних, а також визначаються основні вимоги до оптимальної моделі бази даних.В статье рассматривается поиск оптимальных моделей баз данных и эффективных способов их построения. Рассматриваются традиционные модели данных, а также выявляются их ограничения и недостатки при внедрении в современные информационные системы. Изучаются основные моменты теории нормализации реляционных баз данных, а также определяются основные требования к оптимальной модели базы данных

Validez del índice de katz para evaluar las actividades básicas de vida diaria por informantes en estudios neuropatológicos

OBJECTIVE To analyze the evidences of construct validity of the Katz Index for the retrospective assessment of activities of daily living (ADL) by informants, to assist neuropathological studies in the elderly. METHOD A cross-sectional study analyzed the functional ability of ADL measure by the Katz Index, of 650 cases randomly selected from the Brazilian Brain Bank of the Ageing Brain Study Group (BBBABSG) database. Sample was divided in two subsamples for the analysis (N=325, each) and then stratified according to cognitive decline assessed by the Clinical Dementia Rating Scale (CDR). Factor analyses with calculations of internal consistency and invariance were performed. RESULTS Factor analysis evidenced a unidimensional instrument with optimal internal consistency, in all subgroups. Goodness of fit indices were obtained after two treatments of covariance, indicating adequacy of the scale for assessing ADL by informants. The scale is invariant to cognitive decline meaning that it can be used for subjects with or without cognitive impairment. CONCLUSION Katz Index is valid for the retrospective assessment of basic ADL by informants, with optimal reliability.OBJETIVO Analisar as evidências de validade de constructo do Índice de Katz para a avaliação retrospectiva das Atividades Básicas de Vida Diária (AbVD) por informantes, para apoiar estudos neuropatológicos no envelhecimento. MÉTODO Por meio de estudo transversal foi analisada a capacidade funcional para as AbVD mensurada pelo Índice de Katz em 650 casos randomizados das bases de dados do Banco de Encéfalos Humanos do Grupo de Estudos em Envelhecimento Cerebral (BEHGEEC). A amostra foi particionada em duas subamostras para as análises (N=325, cada) e então estratificada de acordo com o comprometimento cognitivo determinado pelo Escore Clínico de Demência (CDR). Foram realizadas análise fatorial, de consistência interna e de invariância. RESULTADOS A análise fatorial evidenciou um instrumento unidimensional com ótima consistência interna, em todos os grupos. Ótimos índices de ajuste foram obtidos após o tratamento de duas covariâncias, indicando adequação da escala para avaliar AbVD por informantes. A escala é invariante para o comprometimento cognitivo, o que significa que pode ser usada em indivíduos com ou sem comprometimento cognitivo. CONCLUSÃO O Índice de Katz apresenta validade de constructo para a avaliação retrospectiva das AbVD por informantes, com confiabilidade.OBJETIVO Analizar las evidencias de validez de constructo del Índice de Katz para la evaluación retrospectiva de las Actividades Básicas de Vida Diaria (AbVD) por informantes para apoyar estudios neuropatológicos en el envejecimiento. MÉTODO Por medio de estudio transversal se analizó la capacidad funcional para las AbVD mensurada por el Índice de Katz en 650 casos randomizados de las bases de datos del Banco de Encéfalos Humanos del Grupo de Estudios en Envejecimiento Cerebral (BEHGEEC). La muestra fue dividida en dos submuestras para los análisis (N=325, cada) y luego estratificada de acuerdo con el compromiso cognitivo determinado por la Escala de Clasificación de la Demencia Clínica (CDR). Se hicieron análisis factorial, de consistencia interna y de invariancia. RESULTADOS El análisis factorial evidenció un instrumento unidimensional con excelente consistencia interna, en todos los grupos. Excelentes índices de ajuste fueron obtenidos después del tratamiento de dos covariancias, indicando la adecuación de la escala para evaluar AbVD por informantes. La escala es invariante para el compromiso cognitivo, lo que significa que se puede utilizarla en individuos con o sin compromiso cognitivo. CONCLUSIÓN El Índice de Katz presenta validez de constructo para la evaluación retrospectiva de las AbVD por informantes, con confiabilidad

Study on Rough Sets and Fuzzy Sets in Constructing Intelligent Information System

Since human being is not an omniscient and omnipotent being, we are actually living in an uncertain world. Uncertainty was involved and connected to every aspect of human life as a quotation from Albert Einstein said: �As far as the laws of mathematics refer to reality, they are not certain. And as far as they are certain, they do not refer to reality.� The most fundamental aspect of this connection is obviously shown in human communication. Naturally, human communication is built on the perception1-based information instead of measurement-based information in which perceptions play a central role in human cognition [Zadeh, 2000]. For example, it is naturally said in our communication that �My house is far from here.� rather than let say �My house is 12,355 m from here�. Perception-based information is a generalization of measurement-based information, where perception-based information such as �John is excellent.� is hard to represent by measurement-based version. Perceptions express human subjective view. Consequently, they tend to lead up to misunderstanding. Measurements then are needed such as defining units of length, time, etc., to provide objectivity as a means to overcome misunderstanding. Many measurers were invented along with their methods and theories of measurement. Hence, human cannot communicate with measurers including computer as a product of measurement era unless he uses measurement-based information. Perceptions are intrinsic aspect in uncertainty-based information. In this case, information may be incomplete, imprecise, fragmentary, not fully reliable, vague, contradictory, or deficient in some other way. 1In psychology, perception is understood as a process of translating sensory stimulation into an organized experience Generally, these various information deficiencies may express different types of uncertainty. It is necessary to construct a computer-based information system called intelligent information system that can process uncertainty-based information. In the future, computers are expected to be able to make communication with human in the level of perception. Many theories were proposed to express and process the types of uncertainty such as probability, possibility, fuzzy sets, rough sets, chaos theory and so on. This book extends and generalizes existing theory of rough set, fuzzy sets and granular computing for the purpose of constructing intelligent information system. The structure of this book is the following: In Chapter 2, types of uncertainty in the relation to fuzziness, probability and evidence theory (belief and plausibility measures) are briefly discussed. Rough set regarded as another generalization of crisp set is considered to represent rough event in the connection to the probability theory. Special attention will be given to formulation of fuzzy conditional probability relation generated by property of conditional probability of fuzzy event. Fuzzy conditional probability relation then is used to represent similarity degree of two fuzzy labels. Generalization of rough set induced by fuzzy conditional probability relation in terms of covering of the universe is given in Chapter 3. In the relation to fuzzy conditional probability relation, it is necessary to consider an interesting mathematical relation called weak fuzzy similarity relation as a generalization of fuzzy similarity relation proposed by Zadeh [1995]. Fuzzy rough set and generalized fuzzy rough set are proposed along with the generalization of rough membership function. Their properties are examined. Some applications of these methods in information system such as α-redundancy of object and dependency of domain attributes are discussed. In addition, multi rough sets based on multi-context of attributes in the presence of multi-contexts information system is defined and proposed in Chapter 4. In the real application, depending on the context, a given object may have different values of attributes. In other words, set of attributes might be represented based on different context, where they may provide different values for a given object. Context can be viewed as background or situation in which somehow it is necessary to group some attributes as a subset of attributes and consider the subset as a context. Finally, Chapter 5 summarizes all discussed in this book and puts forward some future topics of research

Improving Organizational Decision Making Using a SAF-T based Business Intelligence System

Today, companies need to quickly adapt to business changes and react to customers\u27 tendencies and market demands in an unpredictable environment. In this field, the analytical systems represent an important asset that each company should have and use. Data Warehousing Systems (DWS) support companies\u27 analytical needs, however, the development and integration of the data systems is a critical part. Due to specificities of the involved data, each DWS is unique, which compromises the use of reusable components or even the use of pre-built solutions. In this paper, we propose a standard skeleton for a DWS based on Portuguese Audit Tax documents (SAF-T (PT)). These documents represent a standardized procedure for every Portuguese company, providing the necessary data about billing, accounting, and taxation. Thus, they can provide the foundations to use them as a standard data representation to create a DWS that can be posteriorly explored by analytical techniques to generate useful insights

Relational databases digital preservation

Tese doutoramento - Programa Doutoral em InformáticaWith the expansion and growth of information technologies, much of human knowledge is now recorded on digital media. It began in the 20th century, it has been occurring continuously and it seems that there is no turning back. This paradigm brings scenarios where humans need mediators to understand digital information { computer platforms. These platforms are constantly changing and evolving and nothing can guarantee the continuity of access to digital artifacts in their absence. A new problem in the digital universe arises: Digital Preservation. There are huge volumes of information stored digitally and there are also a panoply of di erent classes, formats and types of digital objects. Our work addresses the problematic Digital Preservation and focuses on the logic and conceptual models within a speci c class of digital objects: Relational Databases. This family of digital objects is used by organizations to record their data produced on daily basis by information systems at operational levels or others. This structures are complex and the relational databases software support may di er from one organization to another. It can be proprietary, free or open source. Previously, a neutral format { Database Markup Language (DBML) { was adopted to pursue the goal of platform independence and to achieve standardization concerning the format in the digital preservation of relational databases. This format is able to describe both data and structure (logical model). The key strategies we are adopting are migration and normalization with refreshment. From our rst approach, we evolved the work to address the preservation of relational databases and we focused on the conceptual model of the database. The conceptual model of the database corresponds to the ideas and concepts that in the basis of the designed and/or modeled database, conceived to support a certain information system. We are referring to the semantics of the database and considering it as an important preservation "property". For the representation of this higher layer of abstraction present in databases we use an ontology based approach. At this higher abstraction level exists inherent Knowledge associated to the database semantics that we tentatively represent using Web Ontology Language (OWL). From the initial prototype, we developed a framework (supported by case studies) and establish a mapping algorithm for the conversion between the database and OWL. The ontology approach is adopted to formalize the knowledge associated to the conceptual model of the database and also a methodology to create an abstract representation of it. The system is based on the functional axes (ingestion, administration, dissemination and preservation) of the Open Archival Information System (OAIS) reference model and its information packages, where we include the two levels/layers of abstraction within the digital objects that are the subject of our research: Relational Databases. The framework o ers a set of web interfaces where it is possible to migrate a database into normalized and neutral formats (DBML + OWL) and perform some minor administration tasks on the repository. The system also enables the navigation or browsing through the database (concepts) without loosing technical details on the database relational model. The end consumers will have at their disposal a broad overview of the preserved object: a) the lower level data and structure of the relational database logical model and b) the higher level semantics and knowledge of the database conceptual model! Considering the unpredicted future access to a preserved database content and structure, our preservation policy tries to capture the signi cant properties of databases that should enable the future interpretability and understanding of the digital object.Através do crescimento das tecnologias de informação, grande parte do conhecimento humano passou a ser armazenado em suportes digitais. Esta transformação iniciou-se no seculo XX, tem vido a ocorrer de forma contínua, e tudo indica que fora já ultrapassado o "ponto-sem-retorno". Este novo paradigma implica cenários substancialmente diferentes, cenários estes onde os seres humanos necessitam de mediadores para compreender a informação digital { plataformas computacionais. Estas plataformas estão em constante evolução e não existe nada que nos possa garantir a continuidade de acesso aos artefactos digitais na sua ausência. Surge um novo problema associado ao mundo digital: Preservação Digital. Grandes quantidades de informação estão armazenadas digitalmente numa panóplia de diferentes classes, formatos e tipos. O nosso trabalho concentra-se na problemática da preservação digital, focando concretamente os modelos lógico e conceptual de uma classe específica de objectos digitais: as Bases de Dados Relacionais. Esta família de objectos digitais é amplamente usada pelas organizações para guardar os dados produzidos diariamente pelos seus sistemas de informação, tanto ao nível operacional como a outros níveis. Falamos de estruturas complexas em que os Sistemas Gestores de Bases de Dados que as suportam podem variar de organização para organização. Os sistemas podem ser proprietários, livres e ou de código aberto ("open source"). Inicialmente, um formato neutro { Database Markup Language (DBML) { foi adotado no sentido de garantir a independência de plataformas, e com o objectivo de conseguir estabelecer um formato normalizado para a preservação de bases de dados relacionais; isto tanto para os dados como para a estrutura (modelo lógico). As estratégias que adoptamos são a migração e normalização com refrescamento. A partir da abordagem inicial, evoluímos o nosso trabalho no que concerne à preservação digital de bases de dados relacionais, focando o estudo também no modelo conceptual da base de dados. O modelo conceptual corresponde às ideias e conceitos na base do desenho e/ou modelação de uma determinada base de dados, e concebido para dar suporte a um determinado cenário "real", i.e., a um determinado sistema de informação. Referimo-nos à semântica da base de dados considerando-a como uma importante "propriedade" na preservação. Para a representação desta camada de abstração mais elevada que estão presente nas bases de dados, utilizamos uma abordagem baseada em ontologias. A este nível mais elevado de abstração existe informação e conhecimento intrínseco que estão associados à semântica da base de dados que se pretende representar através de Web Ontology Language (OWL). A partir do protótipo inicial, desenvolvemos uma plataforma aplicacional (suportada por casos de estudo) e estabelecemos um algoritmo de mapeamento para a conversão entre bases de dados e OWL. A abordagem através da ontologia foi adoptada para formalizar o conhecimento associado ao modelo conceptual da base de dados e também foi usada como uma metodologia para criar uma representação abstracta da base de dados. O sistema baseia-se nos eixos funcionais (ingestão, administração, disseminação e preservação) do modelo de referência Open Archival Information System (OAIS) assim como nos seus pacotes de informação (information packages) onde são incluídos dois níveis/camadas de abstração, relativamente aos objectos digitais que são objecto de preservação neste estudo: Bases de Dados Relacionais. O sistema (framework) fornece um conjunto de interfaces web, onde é possível migrar a base de dados para formatos neutros e normalizados (DBML + OWL), e permitem também executar algumas tarefas de administração do repositório. O sistema possibilita ainda a navegação e pesquisa pelas bases de dados (conceitos), sem que se perca aspectos técnicos associados ao modelo relacional das mesmas. Os consumidores finais têm ao seu dispor uma visão global do objecto preservado: a) a um nível inferior os dados e estrutura do modelo relacional lógico e b) a um nível mais elevado a semântica e conhecimento associado ao modelo conceptual da base de dados! Considerando a imprevisibilidade no acesso futuro ao conteúdo e estrutura de bases de dados preservadas, a nossa política de preservação pretende capturar as propriedades significativas das bases de dados capazes de possibilitar futuramente a interpretação e compreensão do objecto digital