Dissertations / Theses: 'Database theory'

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Butz, C. J. "The relational database theory of Bayesian networks." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0016/NQ54667.pdf.

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Butz, C. J. "The relational database theory of Bayesian networks." Ottawa : National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.nlc-bnc.ca/obj/s4/f2/dsk1/tape3/PQDD%5F0016/NQ54667.pdf.

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3

Krehbiel, Sara. "Strategic behavior and database privacy." Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/53964.

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This dissertation focuses on strategic behavior and database privacy. First, we look at strategic behavior as a tool for distributed computation. We blend the perspectives of game theory and mechanism design in proposals for distributed solutions to the classical set cover optimization problem. We endow agents with natural individual incentives, and we show that centrally broadcasting non-binding advice effectively guides the system to a near-optimal state while keeping the original incentive structure intact. We next turn to the database privacy setting, in which an analyst wishes to learn something from a database, but the individuals contributing the data want to protect their personal information. The notion of differential privacy allows us to do both by obscuring true answers to statistical queries with a small amount of noise. The ability to conduct a task differentially privately depends on whether the amount of noise required for privacy still permits statistical accuracy. We show that it is possible to give a satisfying tradeoff between privacy and accuracy for a computational problem called independent component analysis (ICA), which seeks to decompose an observed signal into its underlying independent source variables. We do this by releasing a perturbation of a compact representation of the observed data. This approach allows us to preserve individual privacy while releasing information that can be used to reconstruct the underlying relationship between the observed variables. In almost all of the differential privacy literature, the privacy requirement must be specified before looking at the data, and the noise added for privacy limits the statistical utility of the sanitized data. The third part of this dissertation ties together privacy and strategic behavior to answer the question of how to determine an appropriate level of privacy when data contributors prefer more privacy but an analyst prefers more accuracy. The proposed solution to this problem views privacy as a public good and uses market design techniques to collect these preferences and then privately select and enforce a socially efficient level of privacy.

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Jiao, Zhuoan. "Optimisation studies in a Prolog object-oriented database." Thesis, University of Aberdeen, 1992. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU047556.

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This thesis is about query optimisation studies in a Prolog object-oriented database (P/FDM). Although many of the query optimisation techniques used in relational database systems can be adapted to solve problems in query optimisation for object-oriented databases (OODBs), there are also many problems that are unique to the OODBs, and new techniques need to be developed. Techniques developed for optimising queries in OODB systems can be categorised into three distinct approaches, namely, algebraic transformation, type-based transformation, and method optimisation. However, few OODB systems have used the combination of all three techniques in the design of their query optimisers. We have adopted an unified approach by combining them into the optimisation strategy of a query optimiser for P/FDM. The overall architecture of the P/FDM query optimiser is based on the top-down framework. The source language of the query optimiser is an extension of Shipman's original DAPLEX language. We choose ZF notation, based on set comprehensions in Zermelo-Frankel (ZF) set theory, to represent the intermediate forms of DAPLEX queries. The target language of optimiser is a set of P/FDM primitives which are implemented in Prolog. We have taken the approach of asking the database to reveal the definitions of methods to the optimiser as privileged code. Most OODB systems do not perform method optimisation because of the difficulties caused by defining methods in a procedural programming language. We have been greatly helped by using a functional programming approach which holds methods in a declarative form, and thus makes it much easier to combine and transform them. Heuristics are incorporated into the query optimisation strategy to avoid exhaustive search, so that the optimiser is able to produce efficient query evaluation plans within satisfactory response times.

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Peng, Yun. "Estimation techniques for advanced database applications." HKBU Institutional Repository, 2013. https://repository.hkbu.edu.hk/etd_ra/1526.

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Aggarwal, Pooja. "Theory and applications of non-blocking slot schedulers." Thesis, IIT Delhi, 2016. http://localhost:8080/iit/handle/2074/7041.

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7

Picalausa, Francois. "Guarded structural indexes: theory and application to relational RDF databases." Doctoral thesis, Universite Libre de Bruxelles, 2013. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209432.

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Ces dernières années ont vu un regain d’intérêt dans l’utilisation de données semi-structurées, grâce à la standardisation de formats d’échange de données sur le Web tels que XML et RDF. On notera en particulier le Linking Open Data Project qui comptait plus de 31 milliard de triplets RDF à la fin de l’année 2011. XML reste, pour sa part, l’un des formats de données privilégié de nombreuses bases de données de grandes tailles dont Uniprot, Open Government Initiative et Penn Treebank.

Cet accroissement du volume de données semi-structurées a suscité un intérêt croissant pour le développement de bases de données adaptées. Parmi les différentes approches proposées, on peut distinguer les approches relationnelles et les approches graphes, comme détaillé au Chapitre 3. Les premières visent à exploiter les moteurs de bases de données relationnelles existants, en y intégrant des techniques spécialisées. Les secondes voient les données semistructurées comme des graphes, c’est-à-dire un ensemble de noeuds liés entre eux par des arêtes étiquetées, dont elles exploitent la structure. L’une des techniques de ce domaine, connue sous le nom d’indexation structurelle, vise à résumer les graphes de données, de sorte à pouvoir identifier rapidement les données utiles au traitement d’une requête.

Les index structurels classiques sont construits sur base des notions de simulation et de bisimulation sur des graphes. Ces notions, qui sont d’usage dans de nombreux domaines tels que la vérification, la sécurité, et le stockage de données, sont des relations sur les noeuds des graphes. Fondamentalement, ces notions caractérisent le fait que deux noeuds partagent certaines caractéristiques telles qu’un même voisinage.

Bien que les approches graphes soient efficaces en pratique, elles présentent des limitations dans le cadre de RDF et son langage de requêtes SPARQL. Les étiquettes sont, dans cette optique, distinctes des noeuds du graphe .Dans le modèle décrit par RDF et supporté par SPARQL, les étiquettes et noeuds font néanmoins partie du même ensemble. C’est pourquoi, les approches graphes ne supportent qu’un sous-ensemble des requêtes SPARQL. Au contraire, les approches relationnelles sont fidèles au modèle RDF, et peuvent répondre au différentes requêtes SPARQL.

La question à laquelle nous souhaitons répondre dans cette thèse est de savoir si les approches relationnelles et graphes sont incompatible, ou s’il est possible de les combiner de manière avantageuse. En particulier, il serait souhaitable de pouvoir conserver la performance des approches graphe, et la généralité des approches relationnelles. Dans ce cadre, nous réalisons un index structurel adapté aux données relationnelles.

Nous nous basons sur une méthodologie décrite par Fletcher et ses coauteurs pour la conception d’index structurels. Cette méthodologie repose sur trois composants principaux. Un premier composant est une caractérisation dite structurelle du langage de requêtes à supporter. Il s’agit ici de pouvoir identifier les données qui sont retournées en même temps par n’importe quelle requête du langage aussi précisément que possible. Un second composant est un algorithme qui doit permettre de grouper efficacement les données qui sont retournées en même temps, d’après la caractérisation structurelle. Le troisième composant est l’index en tant que tel. Il s’agit d’une structure de données qui doit permettre d’identifier les groupes de données, générés par l’algorithme précédent pour répondre aux requêtes.

Dans un premier temps, il faut remarquer que le langage SPARQL pris dans sa totalité ne se prête pas à la réalisation d’index structurels efficaces. En effet, le fondement des requêtes SPARQL se situe dans l’expression de requêtes conjonctives. La caractérisation structurelle des requêtes conjonctives est connue, mais ne se prête pas à la construction d’algorithmes efficaces pour le groupement. Néanmoins, l’étude empirique des requêtes SPARQL posées en pratique que nous réalisons au Chapitre 5 montre que celles-ci sont principalement des requêtes conjonctives acycliques. Les requêtes conjonctives acycliques sont connues dans la littérature pour admettre des algorithmes d’évaluation efficaces.

Le premier composant de notre index structurel, introduit au Chapitre

6, est une caractérisation des requêtes conjonctives acycliques. Cette

caractérisation est faite en termes de guarded simulation. Pour les graphes la

notion de simulation est une version restreinte de la notion de bisimulation.

Similairement, nous introduisons la notion de guarded simulation comme une

restriction de la notion de guarded bisimulation, une extension connue de la

notion de bisimulation aux données relationelles.

Le Chapitre 7 offre un second composant de notre index structurel. Ce composant est une structure de données appelée guarded structural index qui supporte le traitement de requêtes conjonctives quelconques. Nous montrons que, couplé à la caractérisation structurelle précédente, cet index permet d’identifier de manière optimale les données utiles au traitement de requêtes conjonctives acycliques.

Le Chapitre 8 constitue le troisième composant de notre index structurel et propose des méthodes efficaces pour calculer la notion de guarded simulation. Notre algorithme consiste essentiellement en une transformation d’une base de données en un graphe particulier, sur lequel les notions de simulation et guarded simulation correspondent. Il devient alors possible de réutiliser les algorithmes existants pour calculer des relations de simulation.

Si les chapitres précédents définissent une base nécessaire pour un index structurel visant les données relationnelles, ils n’intègrent pas encore cet index dans le contexte d’un moteur de bases de données relationnelles. C’est ce que propose le Chapitre 9, en développant des méthodes qui permettent de prendre en compte l’index durant le traitement d’une requête SPARQL. Des résultats expérimentaux probants complètent cette étude.

Ce travail apporte donc une première réponse positive à la question de savoir s’il est possible de combiner de manière avantageuse les approches relationnelles et graphes de stockage de données RDF.

Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished

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Kim, Pilho. "E-model event-based graph data model theory and implementation /." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/29608.

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Thesis (Ph.D)--Electrical and Computer Engineering, Georgia Institute of Technology, 2010.
Committee Chair: Madisetti, Vijay; Committee Member: Jayant, Nikil; Committee Member: Lee, Chin-Hui; Committee Member: Ramachandran, Umakishore; Committee Member: Yalamanchili, Sudhakar. Part of the SMARTech Electronic Thesis and Dissertation Collection.

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Moreau, Aurélien. "How fuzzy set theory can help make database systems more cooperative." Thesis, Rennes 1, 2018. http://www.theses.fr/2018REN1S043/document.

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Dans ces travaux de thèse nous proposons de tirer parti de la théorie des ensembles flous afin d'améliorer les interactions entre les systèmes de bases de données et les utilisateurs. Les mécanismes coopératifs visent à aider les utilisateurs à mieux interagir avec les SGBD. Ces mécanismes doivent faire preuve de robustesse : ils doivent toujours pouvoir proposer des réponses à l'utilisateur. Empty set (0,00 sec) est un exemple typique de réponse qu'il serait désirable d'éradiquer. Le caractère informatif des explications de réponses est parfois plus important que les réponses elles-mêmes : ce peut être le cas avec les réponses vides et pléthoriques par exemple, d'où l'intérêt de mécanismes coopératifs robustes, capables à la fois de contribuer à l'explication ainsi qu'à l'amélioration des résultats. Par ailleurs, l'utilisation de termes de la langue naturelle pour décrire les données permet de garantir l'interprétabilité des explications fournies. Permettre à l'utilisateur d'utiliser des mots de son propre vocabulaire contribue à la personnalisation des explications et améliore l'interprétabilité. Nous proposons de nous intéresser aux explications dans le contexte des réponses coopératives sous trois angles : 1) dans le cas d'un ensemble pléthorique de résultats ; 2) dans le contexte des systèmes de recommandation ; 3) dans le cas d'une recherche à partir d'exemples. Ces axes définissent des approches coopératives où l'intérêt des explications est de permettre à l'utilisateur de comprendre comment sont calculés les résultats proposés dans un effort de transparence. Le caractère informatif des explications apporte une valeur ajoutée aux résultats bruts, et forme une réponse coopérative
In this thesis, we are interested in how we can leverage fuzzy logic to improve the interactions between relational database systems and humans. Cooperative answering techniques aim to help users harness the potential of DBMSs. These techniques are expected to be robust and always provide answer to users. Empty set (0,00 sec) is a typical example of answer that one may wish to never obtain. The informative nature of explanations is higher than that of actual answers in several cases, e.g. empty answer sets and plethoric answer sets, hence the interest of robust cooperative answering techniques capable of both explaining and improving an answer set. Using terms from natural language to describe data --- with labels from fuzzy vocabularies --- contributes to the interpretability of explanations. Offering to define and refine vocabulary terms increases the personalization experience and improves the interpretability by using the user's own words. We propose to investigate the use of explanations in a cooperative answering setting using three research axes: 1) in the presence of a plethoric set of answers; 2) in the context of recommendations; 3) in the context of a query/answering problem. These axes define cooperative techniques where the interest of explanations is to enable users to understand how results are computed in an effort of transparency. The informativeness of the explanations brings an added value to the direct results, and that in itself represents a cooperative answer

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10

Nelson, David Alan. "To formalise and implement a categorical object-related database system." Thesis, University of Newcastle Upon Tyne, 1999. http://hdl.handle.net/10443/2078.

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The relational data model uses set theory to provide a formal background, thus ensuring a rigorous mathematical data model with support for manipulation. Newer generation database models are based on the object-oriented paradigm, and so fall short of having such a formal background, especially in some of the more complex data manipulation areas. We use category theory to provide a formalism for object databases, in particular the object-relational model. Our model is known as the Product Model. This thesis will describe our formal model for the key aspects of object databases. In particular, we will examine how the Product Model deals with three of the most important problems inherent in object databases, those of queries, closure and views. As well as this, we investigate the more common database concepts, such as keys, relationships and aggregation. We will illustrate the feasibility of this model, by producing a prototype implementation using PIFDM. PIFDM is a semantic data model database system based on the functional model of Shipman, with object-oriented extensions.

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11

Zhao, Wenzhong. "Probabilistic databases and their application." Lexington, Ky. : [University of Kentucky Libraries], 2004. http://lib.uky.edu/ETD/ukycosc2004d00183/wzhao0.pdf.

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Thesis (Ph. D.)--University of Kentucky, 2004.
Title from document title page (viewed Jan. 7, 2005). Document formatted into pages; contains x, 180p. : ill. Includes abstract and vita. Includes bibliographical references (p. 173-178).

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Thorn, Brian K. "Discretionary data bases as public goods : a theory and some experimental findings." Diss., Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/25128.

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Kan, Kin-fai, and 簡健輝. "Maintenance of partial-sum-based histograms." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B26635197.

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Lu, An. "Processing and management of uncertain information in vague databases /." View abstract or full-text, 2009. http://library.ust.hk/cgi/db/thesis.pl?CSED%202009%20LU.

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Burrell, Tiffany. "System Identification in Automatic Database Memory Tuning." Scholar Commons, 2010. https://scholarcommons.usf.edu/etd/1583.

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Databases are very complex systems that require database system administrators to perform system tuning in order to achieve optimal performance. Memory tuning is vital to the performance of a database system because when the database workload exceeds its memory capacity, the results of the queries running on a system are delayed and can cause substantial user dissatisfaction. In order to solve this problem, this thesis presents a platform modeled after a closed control feedback loop to control the level of multi-query processing. Utilizing this platform provides two key assets. First, the system identification is acquired, which is one of two crucial steps involved in developing a closed feedback loop. Second, the platform provides a means to experimentally study database tuning problem and verify the effectiveness of research ideas related to database performance.

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Tan, Chin-Yong. "DB-Prolog : a database programming environment for computer aided control systems design." Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385521.

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Dalvi, Nilesh. "Managing uncertainty using probabilistic databases /." Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/6920.

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Lyn, André T. "Training end-users, the application of cognitive theory to learning a database software package." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0035/MQ27039.pdf.

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Lyn, Andre T. (Andre Tyrone) Carleton University Dissertation Management Studies. "Training end-users: The application of cognitive theory to learning a database software package." Ottawa, 1997.

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20

Lavinus, Joseph W. "Heuristics for laying out information graphs." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-12302008-063333/.

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21

Kim, Mihye Computer Science &amp Engineering Faculty of Engineering UNSW. "Document management and retrieval for specialised domains: an evolutionary user-based approach." Awarded by:University of New South Wales. School of Computer Science and Engineering, 2003. http://handle.unsw.edu.au/1959.4/19183.

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Browsing marked-up documents by traversing hyperlinks has become probably the most important means by which documents are accessed, both via the World Wide Web (WWW) and organisational Intranets. However, there is a pressing demand for document management and retrieval systems to deal appropriately with the massive number of documents available. There are two classes of solution: general search engines, whether for the WWW or an Intranet, which make little use of specific domain knowledge or hand-crafted specialised systems which are costly to build and maintain. The aim of this thesis was to develop a document management and retrieval system suitable for small communities as well as individuals in specialised domains on the Web. The aim was to allow users to easily create and maintain their own organisation of documents while ensuring continual improvement in the retrieval performance of the system as it evolves. The system developed is based on the free annotation of documents by users and is browsed using the concept lattice of Formal Concept Analysis (FCA). A number of annotation support tools were developed to aid the annotation process so that a suitable system evolved. Experiments were conducted in using the system to assist in finding staff and student home pages at the School of Computer Science and Engineering, University of New South Wales. Results indicated that the annotation tools provided a good level of assistance so that documents were easily organised and a lattice-based browsing structure that evolves in an ad hoc fashion provided good efficiency in retrieval performance. An interesting result suggested that although an established external taxonomy can be useful in proposing annotation terms, users appear to be very selective in their use of terms proposed. Results also supported the hypothesis that the concept lattice of FCA helped take users beyond a narrow search to find other useful documents. In general, lattice-based browsing was considered as a more helpful method than Boolean queries or hierarchical browsing for searching a specialised domain. We conclude that the concept lattice of Formal Concept Analysis, supported by annotation techniques is a useful way of supporting the flexible open management of documents required by individuals, small communities and in specialised domains. It seems likely that this approach can be readily integrated with other developments such as further improvements in search engines and the use of semantically marked-up documents, and provide a unique advantage in supporting autonomous management of documents by individuals and groups - in a way that is closely aligned with the autonomy of the WWW.

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Lian, Hongri. "The Design and Development of an Online Database-Driven Peer Assessment Tool Using Division Rule Theory." Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/51803.

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Peer assessment has been adopted as a means of fair and equitable measurement of individual contributions to group work (Cheng and Warren, 2000; Conway and Kember, 1993; Gatfield, 1999; Goldfinch and Raeside, 1990; Lejk and Wyvill, 2001; Lejk, Wyvill, and Farrow, 1996) and it usually requires a certain mechanism or formula to quantify peer assessment criteria. The problem, however, is that it leads to circumstances where a student can be strategic and be easily able to obtain a higher score by simply giving lower scores to other members within a group. The need is to find a new mechanism and the purpose of this study is to develop an Online Database-Driven Peer Assessment Tool (ODDPAT) using the Division Rule mechanism as its core computational algorithm. This developmental study used modified Collaborative Create-Adapt-Generalize (CAG) model (Hicks, Potter, Snider, and Holmes, 2004) as its design and developmental framework. The process of design, development, and evaluation of the entire project was documented. Three experts were interviewed and detailed analysis of data was discussed. Finally, recommendations were made for its implementation and future research.
Ph. D.

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Bezhan, Mohammad Sediq. "Socio-technological Analysis of Development Assistance Database Afghanistan: A Case Study." Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/26115.

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Improvement in information sharing and communication about the foreign aid resources between the donors and the aid-recipient countries have always been considered very important. In recent years, the integration of advanced technology in the area of aid coordination has received a tremendous amount of attention. The following thesis studies the influence of technology in the area aid coordination within the context of Afghanistan. Guided by the Actor-Network Theory, the thesis examines how the social and technological aspects of the Development Assistance Database (DAD), as an advanced aid information management technology, influences aid coordination and information sharing between the donors and the government of Afghanistan. Using a case study methodology, the research also investigates whether or not the DAD adheres to the principles of aid effectiveness. The findings reveal that although technology had a profound impact in the area of aid management in Afghanistan, there are several areas that still face challenges. The present study highlights these challenges and recommends the appropriate solutions.

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Cox, Gary C. "Beyond the Battle Line US Attack Theory and Doctrine, 1914-1941 /." Maxwell AFB, Ala. : Air University Research Coordinator Office, 1998. http://www.au.af.mil/au/database/research/ay1995/saas/coxgc.htm.

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Thesis (M.M.A.S.)--School of Advanced Airpower Studies, 1995.
Subject: The development and usefulness of US air attack theory and doctrine during the interwar period, 1919-1941. Cover page date: June 1995. Vita. Includes bibliographical references.

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Kussard, Michael. "Performance analysis of a controlled database unit with single queue configuration subject to control delays with decision errors." Diss., Online access via UMI:, 2006.

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Hoeppner, Joseph A. "A Comparison of Cloud Computing Database Security Algorithms." UNF Digital Commons, 2015. http://digitalcommons.unf.edu/etd/596.

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The cloud database is a relatively new type of distributed database that allows companies and individuals to purchase computing time and memory from a vendor. This allows a user to only pay for the resources they use, which saves them both time and money. While the cloud in general can solve problems that have previously been too costly or time-intensive, it also opens the door to new security problems because of its distributed nature. Several approaches have been proposed to increase the security of cloud databases, though each seems to fall short in one area or another. This thesis presents the Hoeppner Security Algorithm (HSA) as a solution to these security problems. The HSA safeguards user’s data and metadata by adding fake records alongside the real records, breaking up the database by column or groups of columns, and by storing each group in a different cloud. The efficiency and security of this algorithm was compared to the Alzain algorithm (one of the proposed security solutions that inspired the HSA), and it was found that the HSA outperforms the Alzain algorithm in most every way.

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Weighill, Thomas. "Bifibrational duality in non-abelian algebra and the theory of databases." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/96125.

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Thesis (MSc)--Stellenbosch University, 2014.
ENGLISH ABSTRACT: In this thesis we develop a self-dual categorical approach to some topics in non-abelian algebra, which is based on replacing the framework of a category with that of a category equipped with a functor to it. We also make some first steps towards a possible link between this theory and the theory of databases in computer science. Both of these theories are based around the study of Grothendieck bifibrations and their generalisations. The main results in this thesis concern correspondences between certain structures on a category which are relevant to the study of categories of non-abelian group-like structures, and functors over that category. An investigation of these correspondences leads to a system of dual axioms on a functor, which can be considered as a solution to the proposal of Mac Lane in his 1950 paper "Duality for Groups" that a self-dual setting for formulating and proving results for groups be found. The part of the thesis concerned with the theory of databases is based on a recent approach by Johnson and Rosebrugh to views of databases and the view update problem.
AFRIKAANSE OPSOMMING: In hierdie tesis word ’n self-duale kategoriese benadering tot verskeie onderwerpe in nie-abelse algebra ontwikkel, wat gebaseer is op die vervanging van die raamwerk van ’n kategorie met dié van ’n kategorie saam met ’n funktor tot die kategorie. Ons neem ook enkele eerste stappe in die rigting van ’n skakel tussen hierdie teorie and die teorie van databasisse in rekenaarwetenskap. Beide hierdie teorieë is gebaseer op die studie van Grothendieck bifibrasies en hul veralgemenings. Die hoof resultate in hierdie tesis het betrekking tot ooreenkomste tussen sekere strukture op ’n kategorie wat relevant tot die studie van nie-abelse groep-agtige strukture is, en funktore oor daardie kategorie. ’n Verdere ondersoek van hierdie ooreemkomste lei tot ’n sisteem van duale aksiomas op ’n funktor, wat beskou kan word as ’n oplossing tot die voorstel van Mac Lane in sy 1950 artikel “Duality for Groups” dat ’n self-duale konteks gevind word waarin resultate vir groepe geformuleer en bewys kan word. Die deel van hierdie tesis wat met die teorie van databasisse te doen het is gebaseer op ’n onlangse benadering deur Johnson en Rosebrugh tot aansigte van databasisse en die opdatering van hierdie aansigte.

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Pellegrini, Robert P. "Links Between Science and Philosophy and Military Theory Understanding the Past; Implications for the Future /." Maxwell AFB, Ala. : Air University Research Coordinator Office, 1998. http://www.au.af.mil/au/database/research/ay1995/saas/pellegrp.htm.

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Thesis (M.M.A.S.)--School of Advanced Airpower Studies, 1995.
Subject: An examination of the links between science, philosophy, and military theory. Cover page date: June 1995. Vita. Includes bibliographical references.

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Shapins, Jesse Moss. "Mapping the Urban Database Documentary: Authorial Agency in Utopias of Kaleidoscopic Perception and Sensory Estrangement." Thesis, Harvard University, 2012. http://dissertations.umi.com/gsas.harvard:11021.

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This dissertation theorizes the genre of the urban database documentary, a mode of media art practice that uses structural systems to uncover new perspectives on the lived experience of place. While particularly prominent in recent decades, I argue that the genre of the urban database documentary arises at the turn of the 20th century in response to the rise of the metropolis and the widespread adoption of new media technologies such as photography, cinema, and radio. This was a time when the modern city engendered significant disorientation in its inhabitants, dramatically expanding horizontally and vertically. The rampant pace of technological development at this time also spawned feelings of dehumanization and the loss of connection to embodied experience. The urban database documentary emerges as a symptomatic response to the period's new cultural conditions, meeting a collective need to create order from vast quantities of information and re-frame perception of daily experience. The design of structural systems became a creative method for simultaneously addressing these vast new quantities of information, while attending to the particularities of individual experience. For media artists, building a database into the aesthetic design of a work itself offers an avenue for creatively documenting the radical multiplicity of urbanized environments, preserving attention to the sensory experience of details while aspiring to a legible whole. Crucially, I argue that the design of these systems is a vital form of authorial agency. By reading these artists' work in relation to contemporary practice, I aim to make transparent the underlying, non-technical ambitions that fuel this distinctive mode of media art practice.

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Yoon, Janghyun. "A network-aware semantics-sensitive image retrieval system." Diss., Available online, Georgia Institute of Technology, 2004:, 2003. http://etd.gatech.edu/theses/available/etd-04082004-180459/unrestricted/yoon%5fjanghyun%5f200312%5fphd.pdf.

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Sullivan, Terry. "The Cluster Hypothesis: A Visual/Statistical Analysis." Thesis, University of North Texas, 2000. https://digital.library.unt.edu/ark:/67531/metadc2444/.

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By allowing judgments based on a small number of exemplar documents to be applied to a larger number of unexamined documents, clustered presentation of search results represents an intuitively attractive possibility for reducing the cognitive resource demands on human users of information retrieval systems. However, clustered presentation of search results is sensible only to the extent that naturally occurring similarity relationships among documents correspond to topically coherent clusters. The Cluster Hypothesis posits just such a systematic relationship between document similarity and topical relevance. To date, experimental validation of the Cluster Hypothesis has proved problematic, with collection-specific results both supporting and failing to support this fundamental theoretical postulate. The present study consists of two computational information visualization experiments, representing a two-tiered test of the Cluster Hypothesis under adverse conditions. Both experiments rely on multidimensionally scaled representations of interdocument similarity matrices. Experiment 1 is a term-reduction condition, in which descriptive titles are extracted from Associated Press news stories drawn from the TREC information retrieval test collection. The clustering behavior of these titles is compared to the behavior of the corresponding full text via statistical analysis of the visual characteristics of a two-dimensional similarity map. Experiment 2 is a dimensionality reduction condition, in which inter-item similarity coefficients for full text documents are scaled into a single dimension and then rendered as a two-dimensional visualization; the clustering behavior of relevant documents within these unidimensionally scaled representations is examined via visual and statistical methods. Taken as a whole, results of both experiments lend strong though not unqualified support to the Cluster Hypothesis. In Experiment 1, semantically meaningful 6.6-word document surrogates systematically conform to the predictions of the Cluster Hypothesis. In Experiment 2, the majority of the unidimensionally scaled datasets exhibit a marked nonuniformity of distribution of relevant documents, further supporting the Cluster Hypothesis. Results of the two experiments are profoundly question-specific. Post hoc analyses suggest that it may be possible to predict the success of clustered searching based on the lexical characteristics of users' natural-language expression of their information need.

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Hovad, Josef. "Metody pro práci s grafy v databázi." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2011. http://www.nusl.cz/ntk/nusl-235534.

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The thesis introduces the basic concepts of graph theory and graph representation both in mathematics and programming. Furthermore, it presents basic methods and problems of graphs searching and theory in general. There are presented graph data management capabilities of different database systems including those directly based on the graph theory. In the practical part, there is designed an efficient method of graphs traversing in PostgreSQL database. The method was tested and demonstrated by the graph search algorithms, coloring and isomorphism.

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Warrenburg, Lindsay Alison. "Subtle Semblances of Sorrow: Exploring Music, Emotional Theory, and Methodology." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1566765247386444.

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Lai, Catherine. "A formal framework for linguistic tree query /." Connect to thesis, 2005. http://eprints.unimelb.edu.au/archive/00001594.

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Tancred, James Anderson. "Aerodynamic Database Generation for a Complex Hypersonic Vehicle Configuration Utilizing Variable-Fidelity Kriging." University of Dayton / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1543801033672049.

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Sanghi, Shweta. "Membership Functions for a Fuzzy Relational Database: A Comparison of the Direct Rating and New Random Proportional Methods." VCU Scholars Compass, 2006. http://scholarscompass.vcu.edu/etd/1366.

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Fuzzy relational databases deal with imprecise data or fuzzy information in a relational database. The purpose of this fuzzy database implementation is to retrieve images by using fuzzy queries whose common-language descriptions are defined by the consensus of a particular user community. The fuzzy set, which is presentation of fuzzy attribute values of the images, is determined through membership function. This paper compares two methods of constructing membership functions, the Direct Rating and New Random Proportional, to determine which method gives maximum users satisfaction with minimum feedback from the community. The statistical analysis of results suggests the use of Direct Rating method. Moreover, the analysis shows that the performance of the New Random Proportional method can be improved with the inclusion of a "Not" modifier. This paper also identifies and analyzes issues that are raised by different versions of the database system.

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Arnold, Nathaniel M. "Targeting the Minority: A New Theory of Diversionary Violence." Wright State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=wright1590166439219292.

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West, Raymond Troy Jr. "On the performance of B-trees using dynamic address computation." Thesis, Virginia Tech, 1985. http://hdl.handle.net/10919/41574.

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The B-tree is a one of the more popular methods in use today for indexes and inverted files in database management systems. The traditional implementation of a Bâ tree uses many pointers (more than one per key), which can directly affect the performance of the B-tree. A general method of file organization and access (called Dymanic Address Computation) has been described by Cook that can be used to implement B-trees using no pointers. A minimal amount of storage (in addition to the keys) is required. An implementation of Dynamic Address Computation and a B-tree management package is described. Analytical performance measures are derived in an attempt to understand the performance characteristics of the B-tree. It is shown that the additional costs associated with Dynamic Address Computation result in an implementation that is competitive with traditional implementations only for small applications. For very large B-trees, additional work is required to make the performance acceptable. Some examples of possible modifications are discussed.

Master of Science

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Hai, Bui Thanh. "Group-Theoretical Structure in Multispectral Color and Image Databases." Doctoral thesis, Linköpings universitet, Institutionen för teknik och naturvetenskap, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-3818.

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Many applications lead to signals with nonnegative function values. Understanding the structure of the spaces of nonnegative signals is therefore of interest in many different areas. Hence, constructing effective representation spaces with suitable metrics and natural transformations is an important research topic. In this thesis, we present our investigations of the structure of spaces of nonnegative signals and illustrate the results with applications in the fields of multispectral color science and content-based image retrieval. The infinite-dimensional Hilbert space of nonnegative signals is conical and convex. These two properties are preserved under linear projections onto lower dimensional spaces. The conical nature of these coordinate vector spaces suggests the use of hyperbolic geometry. The special case of three-dimensional hyperbolic geometry leads to the application of the SU(1,1) or SO 2,1) groups. We introduce a new framework to investigate nonnegative signals. We use PCA-based coordinates and apply group theoretical tools to investigate sequences of signal coordinate vectors. We describe these sequences with oneparameter subgroups of SU(1,1) and show how to compute the one-parameter subgroup of SU(1,1) from a given set of nonnegative signals. In our experiments we investigate the following signal sequences: (i) blackbody radiation spectra; (ii) sequences of daylight/twilight spectra measured in Norrk¨oping, Sweden and in Granada, Spain; (iii) spectra generated by the SMARTS2 simulation program; and (iv) sequences of image histograms. The results show that important properties of these sequences can be modeled in this framework. We illustrate the usefulness with examples where we derive illumination invariants and introduce an efficient visualization implementation. Content-Based Image Retrieval (CBIR) is another topic of the thesis. In such retrieval systems, images are first characterized by descriptor vectors. Retrieval is then based on these content-based descriptors. Selection of contentbased descriptors and defining suitable metrics are the core of any CBIR system. We introduce new descriptors derived by using group theoretical tools. We exploit the symmetry structure of the space of image patches and use the group theoretical methods to derive low-level image filters in a very general framework. The derived filters are simple and can be used for multispectral images and images defined on different sampling grids. These group theoretical filters are then used to derive content-based descriptors, which will be used in a real implementation of a CBIR.

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Campbell, Vivian. "A methodology for the selection of a paradigm of reasoning under uncertainty in expert system development." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 1998. https://ro.ecu.edu.au/theses/980.

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The aim of this thesis is to develop a methodology for the selection of a paradigm of reasoning under uncertainty for the expert system developer. This is important since practical information on how to select a paradigm of reasoning under uncertainty is not generally available. The thesis explores the role of uncertainty in an expert system and considers the process of reasoning under uncertainty. The possible sources of uncertainty are investigated and prove to be crucial to some aspects of the methodology. A variety of Uncertainty Management Techniques (UMTs) are considered, including numeric, symbolic and hybrid methods. Considerably more information is found in the literature on numeric methods, than the latter two. Methods that have been proposed for comparing UMTs are studied and comparisons reported in the literature are summarised. Again this concentrates on numeric methods, since there is more literature available. The requirements of a methodology for the selection of a UMT are considered. A manual approach to the selection process is developed. The possibility of extending the boundaries of knowledge stored in the expert system by including meta-data to describe the handling of uncertainty in an expert system is then considered. This is followed by suggestions taken from the literature for automating the process of selection. Finally consideration is given to whether the objectives of the research have been met and recommendations are made for the next stage in researching a methodology for the selection of a paradigm of reasoning under uncertainty in expert system development.

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Paternite, Judith. "The Effects of Problem-Based Learning Versus Structured Tutorials on Student Achievement in a Relational Database Design Activity During Online Concept Learning." Kent State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=kent1467648599.

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Stejskal, Roman. "Zjišťování izomorfizmu grafů v databázi." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2008. http://www.nusl.cz/ntk/nusl-236007.

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This project introduces history and basic notions of the graph theory. It describes graph theory problems, possible graph representations and practical graph management in databases. Aims to subgraph and graph isomorphism. It describes possible ways to find graph isomorphism and chosen algorithms for subgraph and graph isomorphism. The experimental part aims to comparing two implemented algorithms. These are Ullmann and VF2 algorithm. Also searches difference between graphs stored in memory and graphs stored in database.

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Akroun, Lakhdar. "Decidability and complexity of simulation preorder for data-centric Web services." Thesis, Clermont-Ferrand 2, 2014. http://www.theses.fr/2014CLF22523/document.

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Dans cette thèse nous nous intéressons au problème d’analyse des spécifications des protocoles d’interactions des services Web orientés données. La spécification de ce type de protocoles inclut les données en plus de la signature des opérations et des contraintes d’ordonnancement des messages. L’analyse des services orientés données est complexe car l’exécution d’un service engendre une infinité d’états. Notre travail se concentre autour du problème d’existence d’une relation de simulation quand les spécifications des protocoles des services Web sont représentés en utilisant un système à transition orienté données. D’abord nous avons étudié le modèle Colombo [BCG+05]. Dans ce modèle, un service (i) échange des messages en utilisant des variables ; (ii) modifie une base de donnée partagée ; (iii) son comportement est modélisé avec un système à transition. Nous montrons que tester l’existence de la relation de simulation entre deux services Colombo non bornée est indécidable. Puis, nous considérons le cas où les services sont bornés. Nous montrons pour ce cas que le test de simulation est (i) exptime-complet pour les services Colombo qui n’accèdent pas à la base de donnée (noté ColomboDB=∅), et (ii) 2exptime-complet quand le service peut accéder à une base de donnée bornée (Colombobound). Dans la seconde partie de cette thèse, nous avons défini un modèle générique pour étudier l’impact de différents paramètres sur le test de simulation dans le contexte des services Web orientés données. Le modèle générique est un système à transition gardé qui peut lire et écrire à partir d’une base de donnée et échanger des messages avec son environnement (d’autres services ou un client). Dans le modèle générique toutes les actions sont des requêtes sur des bases de données (modification de la base de données, messages échangés et aussi les gardes). Dans ce contexte, nous avons obtenu les résultats suivant : (i) pour les services gardés sans mise à jour, le test de simulation est caractérisé par rapport à la décidabilité du test de satisfiabilité du langage utilisé pour exprimer les gardes augmenté avec une forme restrictive de négation, (ii) pour les services sans mise à jour mais qui peuvent envoyer comme message le résultat d’une requête, nous avons trouvé des conditions suffisantes d’indécidabilité et de décidabilité par rapport au langage utilisé pour exprimer l’échange de messages, et (iii) nous avons étudié le cas des services qui ne peuvent que insérer des tuples dans la base de donnée. Pour ce cas, nous avons étudié la simulation ainsi que la weak simulation et nous avons montré que : (a) la weak simulation est indécidable quand les requêtes d’insertion sont des requêtes conjonctives, (b) le test de simulation est indécidable si la satisfiabilité du langage de requête utilisé pour exprimer les insertions augmenté avec une certaine forme de négation est indécidable. Enfin, nous avons étudié l’interaction entre le langage utilisé pour exprimer les gardes et celui utilisé pour les insertions, nous exhibons une classe de service où la satisfiabilité des deux langages est décidable alors que le test de simulation entre les services qui leur sont associés ne l’est pas
In this thesis we address the problem of analyzing specifications of data-centric Web service interaction protocols (also called data-centric business protocols). Specifications of such protocols include data in addition to operation signatures and messages ordering constraints. Analysis of data-centric services is a complex task because of the inherently infinite states of the underlying service execution instances. Our work focuses on characterizing the problem of checking a refinement relation between service interaction protocol specifications. More specifically, we consider the problem of checking the simulation preorder when service business protocols are represented using data-centric state machines. First we study the Colombo model [BCG+05]. In this framework, a service (i) exchanges messages using variables; (ii) acts on a shared database; (iii) has a transition based behavior. We show that the simulation test for unbounded Colombo is undecidable. Then, we consider the case of bounded Colombo where we show that simulation is (i) exptime-complete for Colombo services without any access to the database (noted ColomboDB=∅), and (ii) 2exptime-complete when only bounded databases are considered (the obtained model is noted Colombobound). In the second part of this thesis, we define a generic model to study the impact of various parameters on the simulation test in the context of datacentric services. The generic model is a guarded transition system acting (i.e., read and write) on databases (i.e., local and shared) and exchanging messages with its environment (i.e., other services or users). The model was designed with a database theory perspective, where all actions are viewed as queries (i.e modification of databases, messages exchanges and guards). In this context, we obtain the following results (i) for update free guarded services (i.e., generic services with guards and only able to send empty messages) the decidability of simulation is fully characterized w.r.t decidability of satisfiability of the query language used to express the guards augmented with a restrictive form of negation, (ii) for update free send services (i.e., generic services without guards and able to send as messages the result of queries over local and shared database), we exhibit sufficient conditions for both decidability and undecidability of simulation test w.r.t the language used to compute messages payloads, and (iii) we study the case of insert services (i.e., generic services without guards and with the ability of insert the result of queries into the local and the shared database). In this case, we study the simulation as well as the weak simulation relations where we show that: (i) the weak simulation is undecidable when the insertions are expressed as conjunctive queries, (ii) the simulation is undecidable if satisfiability of the query language used to express the insertion augmented with a restricted form of negation is undecidable. Finally, we study the interaction between the queries used as guards and the ones used as insert where we exhibit a class of services where satisfiability of both languages is decidable while simulation is undecidable

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Nanongkai, Danupon. "Graph and geometric algorithms on distributed networks and databases." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/41056.

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In this thesis, we study the power and limit of algorithms on various models, aiming at applications in distributed networks and databases. In distributed networks, graph algorithms are fundamental to many applications. We focus on computing random walks which are an important primitive employed in a wide range of applications but has always been computed naively. We show that a faster solution exists and subsequently develop faster algorithms by exploiting random walk properties leading to two immediate applications. We also show that this algorithm is optimal. Our technique in proving a lower bound show the first non-trivial connection between communication complexity and lower bounds of distributed graph algorithms. We show that this technique has a wide range of applications by proving new lower bounds of many problems. Some of these lower bounds show that the existing algorithms are tight. In database searching, we think of the database as a large set of multi-dimensional points stored in a disk and want to help the users to quickly find the most desired point. In this thesis, we develop an algorithm that is significantly faster than previous algorithms both theoretically and experimentally. The insight is to solve the problem on the streaming model which helps emphasize the benefits of sequential access over random disk access. We also introduced the randomization technique to the area. The results were complemented with a lower bound. We also initiat a new direction as an attempt to get a better query. We are the first to quantify the output quality using "user satisfaction" which is made possible by borrowing the idea of modeling users by utility functions from game theory and justify our approach through a geometric analysis.

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Vyroubalová, Ivana. "Moderní metody výuky Teorie obvodů." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2007. http://www.nusl.cz/ntk/nusl-412785.

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This diploma thesis is about design and implementation of an e-learning system to help the students in daily course of Circuits Theory. This system works with different requirements based on special rights for appropriate user-groups. Implementation of the system requires support the specific mathematical formulas, creation of study materials and functions for testing knowledges in Circuits Theory and in Safety work on electrical devices. The system is implemented using XHTML and PHP, the design using cascade style sheets CSS. The educational material is created in XML, MathML and XSL languages and tests are saved in a database. The database is designed using the UML language and implemented in MySQL database system. This system is a part of diploma thesis.

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Loscalzo, Steven. "Group based techniques for stable feature selection." Diss., Online access via UMI:, 2009.

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Pivkina, Inna Valentinovna. "REVISION PROGRAMMING: A KNOWLEDGE REPRESENTATION FORMALISM." Lexington, Ky. : [University of Kentucky Libraries], 2001. http://lib.uky.edu/ETD/ukycosc2001d00022/pivkina.pdf.

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Thesis (Ph. D.)--University of Kentucky, 2001.
Title from document title page. Document formatted into pages; contains vii, 121 p. : ill. Includes abstract. Includes bibliographical references (p. 116-119).

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Lin, Chia-Yang. "Conceptual model builder." CSUSB ScholarWorks, 2004. https://scholarworks.lib.csusb.edu/etd-project/2708.

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Whenever one designs a new database system, an Entity-Relationship Diagram (ER diagram) is always needed to present the structure of this database. Using the graphically well-arranged ER Diagram helps you to easily understand the entities, attributes, domains, primary keys, foreign keys, constraints, and relationships inside a database. This data-modeling tool is an ideal choice for companies and developers.

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Boydens, Isabelle. "Evaluer et améliorer la qualité de l'information: herméneutique des bases de données administratives." Doctoral thesis, Universite Libre de Bruxelles, 1998. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/212039.

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Maryokhin, Tymur. "Data dissemination in large-cardinality social graphs." Thesis, Linnéuniversitetet, Institutionen för datavetenskap (DV), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-48268.

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Near real-time event streams are a key feature in many popular social media applications. These types of applications allow users to selectively follow event streams to receive a curated list of real-time events from various sources. Due to the emphasis on recency, relevance, personalization of content, and the highly variable cardinality of social subgraphs, it is extremely difficult to implement feed following at the scale of major social media applications. This leads to multiple architectural approaches, but no consensus has been reached as to what is considered to be an idiomatic solution. As of today, there are various theoretical approaches exploiting the dynamic nature of social graphs, but not all of them have been applied in practice. In this paper, large-cardinality graphs are placed in the context of existing research to highlight the exceptional data management challenges that are posed for large-scale real-time social media applications. This work outlines the key characteristics of data dissemination in large-cardinality social graphs, and overviews existing research and state-of-the-art approaches in industry, with the goal of stimulating further research in this direction.

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Dissertations / Theses on the topic 'Database theory'

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