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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.
81

Inside the mind of decision makers : antecedents and consequences of managers' mental models /

Grossenbacher, Samuel. January 2008 (has links)
Diss. Universiẗat Bern, 2008. / Im Buchh.: Hamburg : Kovač. Literaturverz.
82

Adaptace XML dokumentů a integritní omezení v XML / XML Document Adaptation and Integrity Constraints in XML

Malý, Jakub January 2013 (has links)
This work examines XML data management and consistency -- more precisely the problem of document adaptation and the usage of integrity constraints. Changes in user requirements cause changes in schemas used in the systems and changes in the schemas subsequently make existing documents invalid. In this thesis, we introduce a formal framework for detecting changes between two versions of a schema and generating a transformation from the source to the target schema. Large-scale information systems depend on integrity constraints to be preserved and valid. In this work, we show how OCL can be used for XML data to define constraints at the abstract level, how such constraints can be translated to XPath expressions and Schematron schemas automatically and verified in XML documents.
83

Multi-Schema-Version Data Management

Herrmann, Kai 19 December 2017 (has links) (PDF)
Modern agile software development methods allow to continuously evolve software systems by easily adding new features, fixing bugs, and adapting the software to changing requirements and conditions while it is continuously used by the users. A major obstacle in the agile evolution is the underlying database that persists the software system’s data from day one on. Hence, evolving the database schema requires to evolve the existing data accordingly—at this point, the currently established solutions are very expensive and error-prone and far from agile. In this thesis, we present InVerDa, a multi-schema-version database system to facilitate agile database development. Multi-schema-version database systems provide multiple schema versions within the same database, where each schema version itself behaves like a regular single-schema database. Creating new schema versions is very simple to provide the desired agility for database development. All created schema versions can co-exist and write operations are immediately propagated between schema versions with a best-effort strategy. Developers do not have to implement the propagation logic of data accesses between schema versions by hand, but InVerDa automatically generates it. To facilitate multi-schema-version database systems, we equip developers with a relational complete and bidirectional database evolution language (BiDEL) that allows to easily evolve existing schema versions to new ones. BiDEL allows to express the evolution of both the schema and the data both forwards and backwards in intuitive and consistent operations; the BiDEL evolution scripts are orders of magnitude shorter than implementing the same behavior with standard SQL and are even less likely to be erroneous, since they describe a developer’s intention of the evolution exclusively on the level of tables without further technical details. Having the developers’ intentions explicitly given in the BiDEL scripts further allows to create a new schema version by merging already existing ones. Having multiple co-existing schema versions in one database raises the need for a sophisticated physical materialization. Multi-schema-version database systems provide full data independence, hence the database administrator can choose a feasible materialization, whereby the multi-schema-version database system internally ensures that no data is lost. The search space of possible materializations can grow exponentially with the number of schema versions. Therefore, we present an adviser that releases the database administrator from diving into the complex performance characteristics of multi-schema-version database systems and merely proposes an optimized materialization for a given workload within seconds. Optimized materializations have shown to improve the performance for a given workload by orders of magnitude. We formally guarantee data independence for multi-schema-version database systems. To this end, we show that every single schema version behaves like a regular single-schema database independent of the chosen physical materialization. This important guarantee allows to easily evolve and access the database in agile software development—all the important features of relational databases, such as transaction guarantees, are preserved. To the best of our knowledge, we are the first to realize such a multi-schema-version database system that allows agile evolution of production databases with full support of co-existing schema versions and formally guaranteed data independence.
84

Sdílení dat mezi informačními systémy založené na ontologiích / Ontology-Based Data Sharing among Information Systems

Hák, Lukáš Unknown Date (has links)
This thesis describes data sharing between information systems based on ontologies. In the first chapter shows up the term ontology and used terminology. Then this thesis analyses used basic methods, onthological languages and partially describes semantic web. In the third chapter are write out  utilities and plugins which are used for working with ontologies. The other chapters describe created ontology which are useful for car-selling. Especially ontology with cars, sellers and addresses . At the end of the thesis is explained suggested instrument to transfer existing XML to recording advertising in OWL language.
85

La nécessité ontologique de la pensée sauvage. Développement et apprentissage dans la théorie de la perception de Maurice Merleau Ponty. Contributions et discussions sur une phénoménologie du schéma corporel dans la petite enfance / The ontological necessity of wild thought. Development and learning in the perception theory of Maurice Merleau-Ponty. Contributions and discussions about a phenomenology of body schema in early childhood

Buffone, Jesica Estefania 22 November 2018 (has links)
L’analyse phénoménologique de l’expérience que Maurice Merleau-Ponty commence à ébaucher dans La structure du comportement (1967) et qui donne forme à la Phénoménologie de la perception (1945) nous rapproche du monde de la vie depuis la perspective de ce que l’auteur lui-même appellera la chair du monde, d’un monde qui nous parle médiatisé par les formalisations abstraites et par la conceptualisation d’une expérience qui nous échappe toujours et qui nous montre le caractère sans cesse fuyant du temps. À travers la nécessité de décrire l’arôme d’un citron et l’acidité de son goût, à travers la nécessité de retourner à ce monde en portant sur lui un regard plus naïf et pétri de notre expérience, nous pouvons trouver la nécessité même d’une analyse phénoménologique de l’enfance. Dans ce retour presque spontané vers la récupération des mouvements libres, du regard surpris, de la synchronie harmonieuse avec la peau des autres, l’enfant semble être non seulement le sujet d’étude de la psychologie (fuyant, complexe, échappant au regard de l’adulte), mais aussi l’image presque métaphorique de la genèse de l’acte perceptuel même, du stade pur et idéal de l’organisation corporelle d’un sujet qui semble arriver au monde doté de quelques outils qui déterminent, avant tout, son aperturité. Psychologie et pédagogie de l’enfant. Cours de Sorbonne (1949-1952) (2001), réunit un ensemble de cours dans lesquels l’auteur s’occupe spécifiquement du problème de l’enfance. Dans cette œuvre (qui constituera le fil conducteur de ce travail), Merleau-Ponty aborde différents aspects liés au développement infantile et à l’interaction entre l’enfant et le monde qui l’entoure. L’acquisition du langage chez l’enfant, la structure de la conscience infantile, l’intelligence, la perception et la relation que l’enfant établit avec les adultes, sont quelques-uns des thèmes que Merleau-Ponty développera tout au long de ces cours et qui ne seront pas seulement l’objet d’une analyse centrée uniquement sur l’étude de la constitution psycho-sociale de l’enfant, mais soulèveront également un certain nombre de questions au sujet de la théorie de la perception pour ceux qui l’abordent.Donc, l'objectif de ce travail est d’analyser les processus qui interviennent dans la construction du schéma corporel pendant la petite enfance, pour ainsi reconstruire la genèse de l’appareil perceptif depuis une perspective phénoménologique. Pour quelle raison l’enfance est-elle importante dans la théorie de la perception de Merleau-Ponty ? Existe-t-il une différence entre la théorie formulée dans la Phénoménologie de la perception et l’ensemble de concepts qui, à propos de ce processus, est présenté dans les cours dédiés à l’enfance ? Le schéma corporel est-il un construit théorique qui s’organise et se redéfinit à partir de dynamiques similaires au processus historique lui-même ? La proprioception, l’imagination, le transfert postural et la construction des habitualités perceptives sont quelques-unes des dynamiques qui seront étudiées de façon critique au sein de sa théorie, pour expliquer l’appropriation et l’utilisation qu’en fait le philosophe français et pour les rapprocher, dans le même temps, de quelques-uns des débats actuels de la psychologie du développement. De la même manière, les processus de constitution et d’organisation perceptive seront mis en dialogue avec la dynamique que Merleau-Ponty décrit comme étant sous-jacente à la temporalité historique et expliqueront ainsi les ruptures et les similitudes entre la définition du corps propre et la relance de l’histoire elle-même. De cette manière, un des principaux objectifs du présent travail sera d’explorer, non seulement les possibilités que la conception de l’enfance de Merleau-Ponty offre pour l’analyse de certains problèmes actuels de la psychologie infantile, mais également d’étudier les voies politiques que semble habiliter sa théorie corporelle de la perception depuis sa définition même du corps. / The phenomenological analysis of the experience that Maurice Merleau-Ponty begins to outline in The Structure of Behavior and which shapes in Phenomenology of Perception brings us closer to the world of life from what he will call the flesh of the world, a world that speaks to us mediated by abstract formalizations and by the conceptualization of an experience that always slips away and that shows us the unattainable side of time. In the need to paint the aroma of a lemon and the acidity of its flavor, in the need to return to that world from a naive and entrenched look in our experience, is where we can find the very need of a phenomenological analysis of childhood. In this almost spontaneous shift towards the recovery of free movements, the surprised look, the harmonic synchrony with the skin of others, the child appears not only as the subject to be studied by psychology (elusive, complex, opaque to the gaze of the adult), but also as a quasi-metaphorical image of the genesis of the perceptual act itself, the pristine and ideal stage of the bodily organization of a subject that seems to arrive in this world provided with a few tools that determine, first of all, its openness. Psychologie et pédagogie de l'enfant. Cours de Sorbonne (1949-1952) (2001), brings together a series of courses in which this author deals especially with the problem of childhood. In this work (which will be the axis of the journey that will be made in this thesis) Merleau-Ponty addresses various aspects related to child development and the child's interaction with the surrounding world. The acquisition of language in the child, the structure of child consciousness, intelligence, perception and the relationship that the child establishes with adults are some of the issues that Merleau-Ponty will develop throughout these courses and that will be unfold not only as analysis confined to the study of the psycho-social constitution of the child, but also they throw us squarely into the midst of certain questions that their theory of perception opens to those who approach it.The aim of this work is to analyze the processes involved in the construction of the body schema during early childhood, in order to reconstruct the genesis of the perceptual apparatus from a phenomenological perspective. Why is childhood important in Merleau-Ponty's theory of perception? Is there any difference between the theory formulated in Phenomenology of perception and the conception that this process holds in the courses dedicated to childhood? Is the body schema a construct that is organized and redefined from dynamics similar to the historical process itself? The proprioception, the imagination, the postural transfer and the construction of the perceptual habitualities are some of the dynamics that will be critically compared in the heart of his theory, to elucidate the appropriation and the use that the French philosopher made of them in order to join them, at the same time, with some current debates in the psychology of development. Likewise, the processes of constitution and perceptual organization will be put in dialogue with the dynamics that Merleau-Ponty describes as underlying historical temporality, elucidating the breaks and similarities between the definition of one's own body and the relaunching of history itself. Thus, one of the main objectives of this work will be to explore not only the possibilities that the conception of Maurice Merleau-Ponty's childhood offers to analyze some current problems of child psychology, but also to investigate the political paths that its body theory of perception seems to enable from its very definition of body. Merleau-Ponty's philosophy becomes, then, "towards the things themselves," to redefine them, to explain them, to make it clear that the construction of the subject of perception is in itself an intersubjective, cultural, historical and political act.
86

Mining XML Integrity Constraints / Mining XML Integrity Constraints

Fajt, Stanislav January 2011 (has links)
The most important integrity constraints in XML are primary keys and foreign keys. In general, keys are essential in understanding both the structure and properties of data. They provide an instrument by which va- lues from a given set of attributes uniquely identify tuples in a database. As a result, keys are important to main database operations. Since XML beco- mes lingua franca for data exchange on the web, it is widely accepted as a model of real world data. Because XML documents in general can appear in any semi-structured form, structural constraints (including keys) are often imposed on the data that are to be modified or processed These constra- ints are formally defined in a schema.Unfortunately, in spite of the obvious advantages, the presence of a schema is not mandatory and many XML do- cuments are not joined with any. Consequently, no integrity constratins are specified in those documents, neither. This thesis is mainly focused on the inference of primary and foreign keys from XML documents. 1
87

Multi-Schema-Version Data Management

Herrmann, Kai 13 December 2017 (has links)
Modern agile software development methods allow to continuously evolve software systems by easily adding new features, fixing bugs, and adapting the software to changing requirements and conditions while it is continuously used by the users. A major obstacle in the agile evolution is the underlying database that persists the software system’s data from day one on. Hence, evolving the database schema requires to evolve the existing data accordingly—at this point, the currently established solutions are very expensive and error-prone and far from agile. In this thesis, we present InVerDa, a multi-schema-version database system to facilitate agile database development. Multi-schema-version database systems provide multiple schema versions within the same database, where each schema version itself behaves like a regular single-schema database. Creating new schema versions is very simple to provide the desired agility for database development. All created schema versions can co-exist and write operations are immediately propagated between schema versions with a best-effort strategy. Developers do not have to implement the propagation logic of data accesses between schema versions by hand, but InVerDa automatically generates it. To facilitate multi-schema-version database systems, we equip developers with a relational complete and bidirectional database evolution language (BiDEL) that allows to easily evolve existing schema versions to new ones. BiDEL allows to express the evolution of both the schema and the data both forwards and backwards in intuitive and consistent operations; the BiDEL evolution scripts are orders of magnitude shorter than implementing the same behavior with standard SQL and are even less likely to be erroneous, since they describe a developer’s intention of the evolution exclusively on the level of tables without further technical details. Having the developers’ intentions explicitly given in the BiDEL scripts further allows to create a new schema version by merging already existing ones. Having multiple co-existing schema versions in one database raises the need for a sophisticated physical materialization. Multi-schema-version database systems provide full data independence, hence the database administrator can choose a feasible materialization, whereby the multi-schema-version database system internally ensures that no data is lost. The search space of possible materializations can grow exponentially with the number of schema versions. Therefore, we present an adviser that releases the database administrator from diving into the complex performance characteristics of multi-schema-version database systems and merely proposes an optimized materialization for a given workload within seconds. Optimized materializations have shown to improve the performance for a given workload by orders of magnitude. We formally guarantee data independence for multi-schema-version database systems. To this end, we show that every single schema version behaves like a regular single-schema database independent of the chosen physical materialization. This important guarantee allows to easily evolve and access the database in agile software development—all the important features of relational databases, such as transaction guarantees, are preserved. To the best of our knowledge, we are the first to realize such a multi-schema-version database system that allows agile evolution of production databases with full support of co-existing schema versions and formally guaranteed data independence.
88

A Declarative Approach to GraphQL Schema Wrapping : wrapping schemas using GraphQL directives / En deklarativ metod för inkapsling av GraphQL-scheman

Jarnemyr, Pontus, Gustafsson, Markus January 2022 (has links)
In recent years, GraphQL has become a popular Web API language. Due to GraphQL’spopularity, third-party libraries have also grown steadily alongside it. One such library isGraphQL Tools, which provides tools such as query delegation and schema wrapping. Onecore element of GraphQL is its schema. In part, the schema describes the relations betweendata in a data source. Every GraphQL server needs a schema, which in turn utilizes resolverfunctions that retrieve the data from the data source. Schema wrapping allows developers to create GraphQL schemas that delegate queriesto another remote server. This allows the user to modify the behavior of the remote schema,without modifying its contents. However, some JavaScript knowledge is required to im-plement the schema wrapping. This thesis proposes a declarative approach to wrappingschemas with the help of custom GraphQL directives. The main objective of the approach isto enable less knowledgeable developers to wrap schemas with less effort. The declarative approach was tested by implementing a prototype. The effects on per-formance was tested with a benchmarking tool called Linköping GraphQL Benchmark(LinGBM). The prototype delegated queries to a remote server also created by LinGBM.The benchmarking tool was run against both the wrapper server and the remote server.The results indicated that the overhead of the wrapper server was mostly due to internalfunctions of GraphQL Tools. Therefore, automatically generating a server with the pro-posed declarative approach did not seem to impose significant performance losses. Con-sidering the decreased programming effort by using the declarative approach, the slightperformance loss can be seen as manageable.
89

Flexibility in Data Management

Voigt, Hannes 07 March 2014 (has links) (PDF)
With the ongoing expansion of information technology, new fields of application requiring data management emerge virtually every day. In our knowledge culture increasing amounts of data and work force organized in more creativity-oriented ways also radically change traditional fields of application and question established assumptions about data management. For instance, investigative analytics and agile software development move towards a very agile and flexible handling of data. As the primary facilitators of data management, database systems have to reflect and support these developments. However, traditional database management technology, in particular relational database systems, is built on assumptions of relatively stable application domains. The need to model all data up front in a prescriptive database schema earned relational database management systems the reputation among developers of being inflexible, dated, and cumbersome to work with. Nevertheless, relational systems still dominate the database market. They are a proven, standardized, and interoperable technology, well-known in IT departments with a work force of experienced and trained developers and administrators. This thesis aims at resolving the growing contradiction between the popularity and omnipresence of relational systems in companies and their increasingly bad reputation among developers. It adapts relational database technology towards more agility and flexibility. We envision a descriptive schema-comes-second relational database system, which is entity-oriented instead of schema-oriented; descriptive rather than prescriptive. The thesis provides four main contributions: (1)~a flexible relational data model, which frees relational data management from having a prescriptive schema; (2)~autonomous physical entity domains, which partition self-descriptive data according to their schema properties for better query performance; (3)~a freely adjustable storage engine, which allows adapting the physical data layout used to properties of the data and of the workload; and (4)~a self-managed indexing infrastructure, which autonomously collects and adapts index information under the presence of dynamic workloads and evolving schemas. The flexible relational data model is the thesis\' central contribution. It describes the functional appearance of the descriptive schema-comes-second relational database system. The other three contributions improve components in the architecture of database management systems to increase the query performance and the manageability of descriptive schema-comes-second relational database systems. We are confident that these four contributions can help paving the way to a more flexible future for relational database management technology.
90

Flexibility in Data Management

Voigt, Hannes 03 March 2014 (has links)
With the ongoing expansion of information technology, new fields of application requiring data management emerge virtually every day. In our knowledge culture increasing amounts of data and work force organized in more creativity-oriented ways also radically change traditional fields of application and question established assumptions about data management. For instance, investigative analytics and agile software development move towards a very agile and flexible handling of data. As the primary facilitators of data management, database systems have to reflect and support these developments. However, traditional database management technology, in particular relational database systems, is built on assumptions of relatively stable application domains. The need to model all data up front in a prescriptive database schema earned relational database management systems the reputation among developers of being inflexible, dated, and cumbersome to work with. Nevertheless, relational systems still dominate the database market. They are a proven, standardized, and interoperable technology, well-known in IT departments with a work force of experienced and trained developers and administrators. This thesis aims at resolving the growing contradiction between the popularity and omnipresence of relational systems in companies and their increasingly bad reputation among developers. It adapts relational database technology towards more agility and flexibility. We envision a descriptive schema-comes-second relational database system, which is entity-oriented instead of schema-oriented; descriptive rather than prescriptive. The thesis provides four main contributions: (1)~a flexible relational data model, which frees relational data management from having a prescriptive schema; (2)~autonomous physical entity domains, which partition self-descriptive data according to their schema properties for better query performance; (3)~a freely adjustable storage engine, which allows adapting the physical data layout used to properties of the data and of the workload; and (4)~a self-managed indexing infrastructure, which autonomously collects and adapts index information under the presence of dynamic workloads and evolving schemas. The flexible relational data model is the thesis\' central contribution. It describes the functional appearance of the descriptive schema-comes-second relational database system. The other three contributions improve components in the architecture of database management systems to increase the query performance and the manageability of descriptive schema-comes-second relational database systems. We are confident that these four contributions can help paving the way to a more flexible future for relational database management technology.

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