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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Data Mining over Hidden Data Sources

Liu, Tantan 24 August 2012 (has links)
No description available.
2

Grid-based semantic integration of heterogeneous data resources : implementation on a HealthGrid

Naseer, Aisha January 2007 (has links)
The semantic integration of geographically distributed and heterogeneous data resources still remains a key challenge in Grid infrastructures. Today's mainstream Grid technologies hold the promise to meet this challenge in a systematic manner, making data applications more scalable and manageable. The thesis conducts a thorough investigation of the problem, the state of the art, and the related technologies, and proposes an Architecture for Semantic Integration of Data Sources (ASIDS) addressing the semantic heterogeneity issue. It defines a simple mechanism for the interoperability of heterogeneous data sources in order to extract or discover information regardless of their different semantics. The constituent technologies of this architecture include Globus Toolkit (GT4) and OGSA-DAI (Open Grid Service Architecture Data Integration and Access) alongside other web services technologies such as XML (Extensive Markup Language). To show this, the ASIDS architecture was implemented and tested in a realistic setting by building an exemplar application prototype on a HealthGrid (pilot implementation). The study followed an empirical research methodology and was informed by extensive literature surveys and a critical analysis of the relevant technologies and their synergies. The two literature reviews, together with the analysis of the technology background, have provided a good overview of the current Grid and HealthGrid landscape, produced some valuable taxonomies, explored new paths by integrating technologies, and more importantly illuminated the problem and guided the research process towards a promising solution. Yet the primary contribution of this research is an approach that uses contemporary Grid technologies for integrating heterogeneous data resources that have semantically different. data fields (attributes). It has been practically demonstrated (using a prototype HealthGrid) that discovery in semantically integrated distributed data sources can be feasible by using mainstream Grid technologies, which have been shown to have some Significant advantages over non-Grid based approaches.
3

Querying semantically heterogeneous data sources using ontologies

Breed, Aditi January 1900 (has links)
Master of Science / Department of Computing and Information Sciences / Doina Caragea / In recent years, we have witnessed a significant increase in the number, size and diversity of the available data sources in many application domains. Data sources in a particular domain are autonomously created and maintained, and therefore distributed and semantically heterogeneous. In this thesis, we focused on the problem of querying such semantically heterogeneous data sources from a user's perspective. We approach this problem by using the concepts of ontologies and mappings between ontologies. A system for answering queries in a transparent way to the user has been designed and implemented. The main components of this system are an ontology mapping algorithm that maps user ontologies to data source ontologies, and a query processing engine that maps user queries to queries that can be answered by the data sources in the system. We have shown that machine learning algorithms can also be incorporated in the system, thus making it possible to learn machine learning classifiers (in particular, generative models such as Naïve Bayes) from distributed, semantically heterogeneous data sources. Because many data sources today are relational in nature, in this work we have dealt specifically with relational data sources, as opposed to flat files, XML or object oriented data sources. However, our system can be easily extended to other types of data sources.
4

Automatic Creation of Researcher’s Competence Profiles Based on Semantic Integration of Heterogeneous Data sources

Khadgi, Vinaya, Wang, Tianyi January 2012 (has links)
The research journals and publications are great source of knowledge produced by the virtue of hard work done by researchers. Several digital libraries have been maintaining the records of such research publications in order for general people and other researchers to find and study the previous work done in the research field they are interested in. In order to make the search criteria effective and easier, all of these digital libraries keep a record/database to store the meta-data of the publications. These meta-data records are generally well design to keep the vital records of the publications/articles, which has the potential to give information about the researcher, their research activities, and hence the competence profile. This thesis work is a study and search of method for building the competence profile of researchers’ base on the records of their publications in the well-known digital libraries. The publications of researchers publish in different publication houses, so, in order to make a complete profile, the data from several of these heterogeneous digital libraries sources have to be integrated semantically. Several of the semantic technologies were studied in order to investigate the challenges of integration of the heterogeneous sources and modeling the researchers’ competence profile .An approach of on-demand profile creation was chosen where user of system could enter some basic name detail of the researcher whose profile is to be created. In this thesis work, Design Science Research methodology was used as the method for research work and to complement this research method with a working artifact, scrum- an agile software development methodology was used to develop a competence profile system as proof of concept.
5

Identificando fontes de dados em modelos de processos de negócios com base em elementos de BPMN

Balbinot, Marcelo January 2017 (has links)
A Notação e Modelo de Processo de Negócio (BPMN - Business Process Model and Notation) possibilita apresentar informações sobre o fluxo de dados de um processo por meio de dados e artefatos, tais como objetos, associações e repositórios de dados. No entanto, esses elementos apresentam poder de expressão limitado, principalmente quando se referem ao mapeamento das fontes de dados (ex.: serviço web) em um modelo de processo. Neste contexto, o presente trabalho propõe uma abordagem para associar fontes de dados a elementos de BPMN (ex.: tarefa de serviço). Tal abordagem deve servir como um ponto de partida para profissionais de gerenciamento de processos de negócio quanto ao mapeamento, na etapa de modelagem, da fonte de dados que está sendo utilizada pelo processo, através da utilização de elementos de BPMN. Visando demonstrar os resultados, foram evidenciadas cinco correlações, que são chamadas de “propostas de definições”, seguidas por sua descrição textual e um exemplo de uso. Essas propostas de definições, juntamente com as fontes de dados utilizadas, foram avaliadas por meio de uma pesquisa de opinião. Como resultado, destaca-se que as fontes de dados selecionadas foram validadas pelos participantes da pesquisa de opinião, que demonstraram conhecimento em ao menos uma das fontes de dados, fornecendo indícios que as fontes de dados selecionadas são as mais apropriadas para o trabalho em questão. Ainda, como resultados, as propostas de definições foram validadas com os participantes, obtendo resultados positivos quanto aos fragmentos de processo elaborados para representar as fontes de dados internos, transferência de arquivos e base de dados compartilhada. A principal contribuição deste trabalho é auxiliar na identificação de fontes de dados de um processo de negócio, a partir do conjunto de elementos disponibilizado pela BPMN 2.0.2, onde, anteriormente, tal identificação era possível apenas através da documentação do processo. / Business Process Model and Notation (BPMN) makes it possible to display information about the data flow of a process through data and artifacts such as objects, associations and data stores. However, these elements provide a limited capacity, especially when referring to the mapping of the data sources (e.g. web service) in a process model. In this context, this paper proposes an approach to associate data sources to BPMN elements (e.g. service task). Such approach aims to serve as a starting point to business process management professionals in order to map, in design time, the data source that is being used by the process, through the use of BPMN elements. In order to demonstrate the results, five correlations were evidenced, which are called “definitions proposals”, followed by their textual description and an example of use. These definitions proposals, together with the data sources used, were evaluated through a survey. As a result, the selected data sources were validated by the participants of the survey that demonstrated knowledge in at least one of the data sources, providing evidence that the selected data sources are the most appropriated for the work concerned. Also, as results, the definitions proposals were validated with the participants, obtaining positive results regarding to the process fragments designed to represent the data sources internal data, file transfer and shared database. The main contribution of this thesis is to assist the identification of data sources of a business process, from the set of elements provided by BPMN 2.0.2, where, previously, such identification was only possible through the process documentation.
6

Verlustzeitenbasierte LSA-Steuerung eines Einzelknotens

Oertel, Robert, Wagner, Peter, Krimmling, Jürgen, Körner, Matthias 24 July 2012 (has links) (PDF)
Neue Methoden zur Verkehrsdatenerfassung wie die Fahrzeug-Infrastruktur-Kommunikation, der Floating Car-Ansatz und die Videodetektion eröffnen die Möglichkeit, neue Verfahren zur verkehrsabhängigen Lichtsignalanlagensteuerung zu realisieren. In dem Beitrag wird ein Verfahren beschrieben, das aus diesen Quellen Daten in Form von Fahrzeugverlustzeiten direkt zur Steuerung eines Einzelknotens verwendet. Die robuste Ausgestaltung des Verfahrens sorgt dabei dafür, dass auch mit einer lückenhaften Datenlage, wie z. B. aufgrund geringer Ausstattungsraten kommunikationsfähiger Fahrzeuge, angemessen umgegangen werden kann. Mit Hilfe einer mikroskopischen Simulationsstudie wird nachgewiesen, dass das neue Verfahren bei der Qualität des Verkehrsablaufs das gleiche Niveau wie eine traditionelle Zeitlückensteuerung erreicht oder dieses unter bestimmten Bedingungen sogar übersteigt. Mit abnehmender Ausstattungsrate ergibt sich dabei allerdings ein Qualitätsverlust, der ebenfalls mit Hilfe der mikroskopischen Simulation quantifiziert wird und wichtige Erkenntnisse für einen möglichen Praxistest liefert. / State-of-the-art traffic data sources like Car-to-Infrastructure communication, Floating Car Data and video detection offer great new prospects for vehicle-actuated traffic signal control. Due to this, the article deals with a recent approach which uses vehicles’ delay times for real-time control of traffic signals at an isolated intersection. One of the strengths of the new approach is that it can handle also incomplete data sets, e.g. caused by low penetration rates of vehicles equipped with Car-to-Infrastructure communication technology, in an appropriate manner. Based on a microscopic simulation study the high quality of this innovative approach is demonstrated, which is equal or even outperforms the well-known headway-based control. However, a decreasing penetration rate of equipped vehicles means a reduced quality of signals’ control, which is quantified in the microscopic simulation study, too, and provides useful information for tests in the field.
7

Retrieving information from heterogeneous freight data sources to answer natural language queries

Seedah, Dan Paapanyin Kofi 09 February 2015 (has links)
The ability to retrieve accurate information from databases without an extensive knowledge of the contents and organization of each database is extremely beneficial to the dissemination and utilization of freight data. The challenges, however, are: 1) correctly identifying only the relevant information and keywords from questions when dealing with multiple sentence structures, and 2) automatically retrieving, preprocessing, and understanding multiple data sources to determine the best answer to user’s query. Current named entity recognition systems have the ability to identify entities but require an annotated corpus for training which in the field of transportation planning does not currently exist. A hybrid approach which combines multiple models to classify specific named entities was therefore proposed as an alternative. The retrieval and classification of freight related keywords facilitated the process of finding which databases are capable of answering a question. Values in data dictionaries can be queried by mapping keywords to data element fields in various freight databases using ontologies. A number of challenges still arise as a result of different entities sharing the same names, the same entity having multiple names, and differences in classification systems. Dealing with ambiguities is required to accurately determine which database provides the best answer from the list of applicable sources. This dissertation 1) develops an approach to identify and classifying keywords from freight related natural language queries, 2) develops a standardized knowledge representation of freight data sources using an ontology that both computer systems and domain experts can utilize to identify relevant freight data sources, and 3) provides recommendations for addressing ambiguities in freight related named entities. Finally, the use of knowledge base expert systems to intelligently sift through data sources to determine which ones provide the best answer to a user’s question is proposed. / text
8

Identificando fontes de dados em modelos de processos de negócios com base em elementos de BPMN

Balbinot, Marcelo January 2017 (has links)
A Notação e Modelo de Processo de Negócio (BPMN - Business Process Model and Notation) possibilita apresentar informações sobre o fluxo de dados de um processo por meio de dados e artefatos, tais como objetos, associações e repositórios de dados. No entanto, esses elementos apresentam poder de expressão limitado, principalmente quando se referem ao mapeamento das fontes de dados (ex.: serviço web) em um modelo de processo. Neste contexto, o presente trabalho propõe uma abordagem para associar fontes de dados a elementos de BPMN (ex.: tarefa de serviço). Tal abordagem deve servir como um ponto de partida para profissionais de gerenciamento de processos de negócio quanto ao mapeamento, na etapa de modelagem, da fonte de dados que está sendo utilizada pelo processo, através da utilização de elementos de BPMN. Visando demonstrar os resultados, foram evidenciadas cinco correlações, que são chamadas de “propostas de definições”, seguidas por sua descrição textual e um exemplo de uso. Essas propostas de definições, juntamente com as fontes de dados utilizadas, foram avaliadas por meio de uma pesquisa de opinião. Como resultado, destaca-se que as fontes de dados selecionadas foram validadas pelos participantes da pesquisa de opinião, que demonstraram conhecimento em ao menos uma das fontes de dados, fornecendo indícios que as fontes de dados selecionadas são as mais apropriadas para o trabalho em questão. Ainda, como resultados, as propostas de definições foram validadas com os participantes, obtendo resultados positivos quanto aos fragmentos de processo elaborados para representar as fontes de dados internos, transferência de arquivos e base de dados compartilhada. A principal contribuição deste trabalho é auxiliar na identificação de fontes de dados de um processo de negócio, a partir do conjunto de elementos disponibilizado pela BPMN 2.0.2, onde, anteriormente, tal identificação era possível apenas através da documentação do processo. / Business Process Model and Notation (BPMN) makes it possible to display information about the data flow of a process through data and artifacts such as objects, associations and data stores. However, these elements provide a limited capacity, especially when referring to the mapping of the data sources (e.g. web service) in a process model. In this context, this paper proposes an approach to associate data sources to BPMN elements (e.g. service task). Such approach aims to serve as a starting point to business process management professionals in order to map, in design time, the data source that is being used by the process, through the use of BPMN elements. In order to demonstrate the results, five correlations were evidenced, which are called “definitions proposals”, followed by their textual description and an example of use. These definitions proposals, together with the data sources used, were evaluated through a survey. As a result, the selected data sources were validated by the participants of the survey that demonstrated knowledge in at least one of the data sources, providing evidence that the selected data sources are the most appropriated for the work concerned. Also, as results, the definitions proposals were validated with the participants, obtaining positive results regarding to the process fragments designed to represent the data sources internal data, file transfer and shared database. The main contribution of this thesis is to assist the identification of data sources of a business process, from the set of elements provided by BPMN 2.0.2, where, previously, such identification was only possible through the process documentation.
9

Identificando fontes de dados em modelos de processos de negócios com base em elementos de BPMN

Balbinot, Marcelo January 2017 (has links)
A Notação e Modelo de Processo de Negócio (BPMN - Business Process Model and Notation) possibilita apresentar informações sobre o fluxo de dados de um processo por meio de dados e artefatos, tais como objetos, associações e repositórios de dados. No entanto, esses elementos apresentam poder de expressão limitado, principalmente quando se referem ao mapeamento das fontes de dados (ex.: serviço web) em um modelo de processo. Neste contexto, o presente trabalho propõe uma abordagem para associar fontes de dados a elementos de BPMN (ex.: tarefa de serviço). Tal abordagem deve servir como um ponto de partida para profissionais de gerenciamento de processos de negócio quanto ao mapeamento, na etapa de modelagem, da fonte de dados que está sendo utilizada pelo processo, através da utilização de elementos de BPMN. Visando demonstrar os resultados, foram evidenciadas cinco correlações, que são chamadas de “propostas de definições”, seguidas por sua descrição textual e um exemplo de uso. Essas propostas de definições, juntamente com as fontes de dados utilizadas, foram avaliadas por meio de uma pesquisa de opinião. Como resultado, destaca-se que as fontes de dados selecionadas foram validadas pelos participantes da pesquisa de opinião, que demonstraram conhecimento em ao menos uma das fontes de dados, fornecendo indícios que as fontes de dados selecionadas são as mais apropriadas para o trabalho em questão. Ainda, como resultados, as propostas de definições foram validadas com os participantes, obtendo resultados positivos quanto aos fragmentos de processo elaborados para representar as fontes de dados internos, transferência de arquivos e base de dados compartilhada. A principal contribuição deste trabalho é auxiliar na identificação de fontes de dados de um processo de negócio, a partir do conjunto de elementos disponibilizado pela BPMN 2.0.2, onde, anteriormente, tal identificação era possível apenas através da documentação do processo. / Business Process Model and Notation (BPMN) makes it possible to display information about the data flow of a process through data and artifacts such as objects, associations and data stores. However, these elements provide a limited capacity, especially when referring to the mapping of the data sources (e.g. web service) in a process model. In this context, this paper proposes an approach to associate data sources to BPMN elements (e.g. service task). Such approach aims to serve as a starting point to business process management professionals in order to map, in design time, the data source that is being used by the process, through the use of BPMN elements. In order to demonstrate the results, five correlations were evidenced, which are called “definitions proposals”, followed by their textual description and an example of use. These definitions proposals, together with the data sources used, were evaluated through a survey. As a result, the selected data sources were validated by the participants of the survey that demonstrated knowledge in at least one of the data sources, providing evidence that the selected data sources are the most appropriated for the work concerned. Also, as results, the definitions proposals were validated with the participants, obtaining positive results regarding to the process fragments designed to represent the data sources internal data, file transfer and shared database. The main contribution of this thesis is to assist the identification of data sources of a business process, from the set of elements provided by BPMN 2.0.2, where, previously, such identification was only possible through the process documentation.
10

MITIGATION OF RISKS OF MAPPING COMPLEX DATA SOURCES ON THE EXAMPLE OF SOLVENCY II PROJECT / Mitigace rizik mapování komplexních datových zdrojů na příkladu Solvency II projektu

Abrahamyan, Nazeli January 2015 (has links)
The purpose of this diploma thesis is to describe the basic principles of Business Intelligence, its meaning in business reporting with focus on ensuring relevant information for stakeholders and consequently to identify the major risk factors in complex data mapping process of a project carried out for an insurance company Solvency II regulatory reporting. The identification of risks is based on a detailed analysis of the mapping process and its weak points. The main benefit of the thesis will then be the proposed methods by which the risks are mitigated or entirely eliminated. The diploma thesis is focused on specific project, which delivers complex Business Intelligence solution in compliance with Solvency II European insurance regulatory reform. Therefore the flawless mapping of data and mitigation of risks are key to meet the Solvency II requirements on reporting in high quality. The introductory section of the thesis is devoted to definition of Business intelligence and its purpose in organizations. This part also includes the definition of key aspects of successful business reporting and its role in effective decision-making. The other part of the introductory section shortly represents the BI architecture and components of specific Solvency II BI solution. The second main section of the work defines the Solvency II project and describes the specificities of its implementation on a specific project for unnamed organization. Based on the experience of this project is then further described the mapping process of complex data sources. The result is a list of risks arising at each stage of mapping activities. As a completion of the main objective of the thesis there are suggested ways of mitigation for each risk. The benefit of this thesis is that identified risks and the recommendations for their mitigation might lead to more effective project management, increase the quality of its outcomes and satisfaction of company clients.

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