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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.
271

Semantinių web technologijų tyrimas ir taikymas video paskaitų sistemoje VIPS / Semantic web technology research and application in video lecturing system VIPS

Karazinas, Evaldas 28 January 2008 (has links)
Šis dokumentas nagrinėja paieškos organizavimo galimybes VIPS sistemos video įrašų archyve pasitelkiant semantines web technologijas. Semantinis žiniatinklis yra dalis pasaulinio interneto, kuriame informacija gali būti suprantama ne tik žmonėms, bet ir programiniams agentams, sukuriant galimybes surasti, pasidalinti ir intergruoti informacija adug paprasčiau. Socialinis žymėjimas taip pat gali grupuoti informaciją semantiniu būdu. Dokumento pradžioje aptariama teorija ir galimi sprendimai, vėliau pateikiamas galimas sprendimo modelis. Dokumentas pabaigiamas išvadomis ir rekomendacijomis. / The aim of this paper is to present search organization opportunities in VIPS system archive in semantic manner. The Semantic Web is an evolving extension of the World Wide Web in which web content can be expressed not only in natural language, but also in a format that can be read and used by software agents, thus permitting them to find, share and integrate information more easily. Social tagging can also group information in semantic manner. Theoretical background of specified model is delivered in the beginning sections of this thesis. As experimental solution information system was introduced. Thesis is concluded and recommendations are suggested for future.
272

Developing a Modular Hydrogeology Ontology Extending the Sweet Ontologies

Tripathi, Ajay 08 August 2005 (has links)
Application of ontologies in the environmental science will allow experts in this field to model their domain knowledge for more efficient exchange and reuse. This thesis presents a modular approach in reengineering existing upper-level ontologies to conceptualize specific domain knowledge. The aim of extending these upper-level ontologies is to tailor and transform the existing conceptual models into new ones designed for the use in a specific domain in the earth sciences. This thesis extends the upper-level Semantic Web for Earth and Environmental Terminology (SWEET)ontologies to develop ontologies for part of the hydrogeology domain. The existing SWEET ontologies are developed by NASA’s Jet Propulsion lab for Earth system science (http://sweet.jpl.nasa.gov/ontology/). In the new model, presented in this thesis, the architecture and orthogonal design of the SWEET ontologies is not disturbed but restructured at certain levels. New concepts are added to the old structure and the consistency is maintained for use by other domains. This thesis discusses the useful steps,necessary tools and other procedures involved in ontological reengineering of existing upper-level ontologies. The hydrogeology domain modeled in this thesis by means of reengineering, exemplifies the reusability methodology for the Earth system science knowledge base.
273

Socialinio tinklo kūrimas semantinio žiniatinklio pagrindu / Creating social network on the basis of semantic web

Adžgauskas, Justas 28 January 2008 (has links)
Šiame darbe apibrėžiamos socialinio tinklo realizavimo galimybės internetinėje aplinkoje semantinio tinklalapio pagrindu. Aprašytos pagrindinės internetinio socialinio tinklo kūrimo technologijos, tokio sistemų tipų funkcionalumas, pasiūlytas sistemos ontologijos modelio išskaidymo į mažesnius modelius metodas, suprojektuotas ir sukurtas eksperimentinis namų bendrijos socialinis tinklas semantinio žiniatinklio pagrindu su išskaidytu sistemos ontologijos modeliu. / In this work are described the opportunities of realization of social network in the internet environment on a semantic web basis. In this work are described main technologies which we can use creating internet social network, functionality of this type of systems, offered system ontology model resolution into lesser models method, projected and created the experimental social network for house communities on a semantic web basis with resolved system ontology model.
274

OWL 2 ontologijų taikymo interneto portaluose metodika / Methodology for applying OWL 2 ontologies in Web portals

Gaurilčikas, Mindaugas 13 August 2012 (has links)
Vienas iš esminių semantinio tinklo komponentų yra ontologijos. Ontologija yra tam tikros dalykinės srities sąvokų visumos specifikavimas išreikštu pavidalu. Semantiniai interneto portalai naudoja ontologijas kaip žinių bazę. Tačiau ontologijų kūrimas nėra toks paprastas, todėl reikia metodikos, kaip aprašyti dalykinę sritį ontologijų kalba, kad ji būtų realizuojama interneto portale, atitiktų vartotojų poreikius ir ontologijų kokybės kriterijus. Šio magistrinio darbo tikslas yra padidinti semantinių portalų kūrimo galimybes sudarant ir praktiškai išbandant metodiką, pagal kurią portalų kūrėjai galėtų kurti semantinius portalus, panaudodami dalykinės srities ontologiją. Darbe aprašyta ontologija grindžiamo portalo kūrimo metodika, kuri glaudžiai susijusi su dalykinės srities ontologijos sudarymo procesu; panaudotos ontologijos modelio saugojimo reliacinėje duomenų bazėje galimybės, atliktas ontologijos savybių rodiklių skaičiavimas. / Web portals collects the information scattered on the internet and organizes it for easy search and access. Current Web technologies employed to build up these portals present serious limitations regarding information search, access, extraction, interpretation and processing. The Semantic Web provides a common framework that allows data to be shared, reused and processed directly and indirectly by machines. To facilitate this process, OWL have been developed as standard formats for the sharing and integration of data in the form of rich conceptual schemas called ontologies. An ontology defines a common vocabulary for researchers who need to share information in a specific domain. There are several methods for facilitating development of ontologies. Although, neither describes how to build a Semantic Web portals step by step, using the latest Web portals development tools and technologies. The main goal of this work is to propose a development methodology for building Semantic Web portals from the scratch.
275

A Knowledge Management Framework to Develop, Model, ALign and Operationalize Clinical Pathways to Provide Decision Support for Comorbid Diseases

Abidi, Samina Raza 16 July 2010 (has links)
The objective of this thesis is to formalize, model, align and operationalize the evidence-based clinical algorithms of co-morbid chronic heart failure (CHF) and atrial fibrillation (AF) in order to provide clinical recommendations, care coordination and decision support to general practitioners (GPs). This thesis addresses following healthcare knowledge modeling issues: (a) modeling of healthcare knowledge, especially in terms of clinical guidelines and clinical pathways, to develop an ontology-based knowledge model for handling co-morbid diseases; (b) computerization of clinical pathways to offer point-of-care decision support; (c) alignment of ontologically-modeled disease-specific clinical pathways to handle co-morbid diseases; and (d) the provision of computerized decision support to GPs, based on modeled clinical guidelines and pathways, to assist them in handling co-morbid diseases. An elaborate OWL CP ontology for co-morbid CHF and AF was developed that can be executed to support the diagnosis and management of co-morbid CHF and AF in a general practice setting. / In this thesis we present an ontology based decision-support framework for handling co-morbidities by the alignment of ontologically modeled clinical practice guidelines (CPGs). The objective of this thesis is to formalize, model, align and operationalize the evidence-based clinical algorithms of co-morbid chronic heart failure (CHF) and atrial fibrillation (AF) in order to provide evidence-based clinical recommendations, care coordination and decision support to general practitioners (GPs) for effective management of CHF and AF. In this regard, the thesis addresses the following healthcare knowledge modeling issues: (a) modeling of healthcare knowledge, especially in terms of clinical guidelines and clinical pathways, to develop an ontology-based healthcare knowledge model for handling co-morbid diseases; (b) computerization of clinical pathways to offer point-of-care decision support; (c) alignment of ontologically-modeled disease-specific clinical pathways to handle co-morbid diseases; and (d) the provision of computerized decision support to general practitioners, based on modeled clinical guidelines and pathways, to assist them in handling chronic and co-morbid diseases. An elaborate OWL CP ontology for co-morbid CHF and AF—the CP ontology was developed that can be executed to support the diagnosis and management of co-morbid CHF and AF in a general practice setting. We have developed a decision support framework termed COMET (Co-morbidity Ontological Modeling & ExecuTion) that can handle three patient care scenarios, (i) patient has CHF; (ii) patient has AF; and (iii) patient develops a co-morbidity of both AF and CHF. COMET is accessible by web and is designed for GPs. COMET has been evaluated, both by simulated cases and by health professionals (GP and specialist), for its ability to handle single disease and comorbid care scenarios based on patient data and related constraints. The output at every phase is compared with the expected output as per single disease or comorbid management. Our results show that the resultant sequence of plans and their outcomes are comparable to the CP knowledge. Also, our ontology was able to handle any updates in the CP knowledge as advised by the domain experts
276

K-MORPH: Knowledge Morphing via Reconciliation of Contextualized Sub-ontologies

Hussain, Syed Sajjad 29 March 2011 (has links)
Knowledge-driven problem solving demands 'complete' knowledge about the domain and its interpretation under different contexts. Knowledge Morphing aims at a context-driven integration of heterogeneous knowledge sources--in order to provide a comprehensive and networked view of all knowledge about a domain-specific problem, pertaining to the context at hand. In this PhD thesis, we have proposed a Semantic Web based framework, K-MORPH, for Knowledge Morphing via Reconciliation of Contextualized Sub-ontologies. In order to realize our K-MORPH framework, we have developed: (i) a sub-ontology extraction method for generating contextualized sub-ontologies from the source ontologies pertinent to the problem-context at hand; (ii) two ontology matching approaches: triple-based ontology matching (TOM) and proof-based ontology matching (POM) for finding both atomic and complex correspondences between two extracted contextualized sub-ontologies; and (iii) our approach for resolving inconsistencies in ontologies by generating minimal inconsistent resolve candidates (MIRCs), where removing any of the MIRCs from the inconsistent ontology results in a maximal consistent sub-ontology. Thus, K-MORPH performs knowledge morphing among ontology-modelled knowledge sources and generates a context-sensitive and comprehensive knowledge-base pertinent to the problem at hand by (a) extracting problem-specific knowledge components from ontology-modelled knowledge sources using our sub-ontology extraction method; (b) aligning and merging the extracted knowledge components using our matching approaches; and (c) repairing inconsistencies in the morphed knowledge by applying our approach for detecting and resolving inconsistencies. We demonstrated the application of our K-MORPH framework in the healthcare domain, where K-MORPH generated a merged ontology for providing a comprehensive therapeutic knowledge-base for Urinary Tract Infections (UTI) by first (i) extracting 20 contextualized sub-ontologies from various UTI ontologies of different healthcare institutions, (ii) aligning and merging the extracted UTI sub-ontologies, and (iii) detecting and resolving inconsistencies in the merged UTI ontology.
277

Vizualinis šablono sudarymas informacijos gavimui iš internetinių šaltinių / Visual composition of a pattern for data retrieval from the internet

Černiauskas, Karolis 21 August 2013 (has links)
Duomenų gausa internete didėja eksponentiškai. Žmonės patys nesugeba susidoroti su kasdien didėjančia įvairių duomenų paklausa. Norint apdoroti didelius duomenų kiekius yra naudojami kompiuteriai, tačiau dabartinė programinė įranga negali suprasti daugumos internete saugomų duomenų. Šiame darbe siekiama ištirti metodus, kuriais galima būtų semantizuoti interneto duomenų šaltinius ir pateikiamas vizualinio įrankio, kuris padėtų tai padaryti, projektas. / The amount of data in the Web is increasing exponentially. Humans by themselves are not able to cope with the increasing demand of various data every day. In our every day lives this manifests in struggle to schedule everything as tightly as possible and absorb as much information as possible in as little time as possible. To aid in the increasing demand of data, computers have been used almost as much increasingly well. However, current state of the Web (which provides us with almost all everyday data) is not perfect for usage by automated computers. The Internet mostly provides us with data in text or image format that computers can merely display, but they can not comprehend the meaning of it. This situation calls for a solution which involves semanticizing current text-only Internet, i.e. giving meaning to the text, which computers could understand and manipulate as well as humans do now. This paper investigates the means to approach the lack of machine understandable text on the Web and suggests a tool which can aid humans in semanticizing it.
278

Semantinių web servisų pritaikymas elektroniniame versle / Semantic web services adaptation in e-business

Mažeika, Kęstutis 15 June 2011 (has links)
Informacinės technologijos besivysto sparčiu tempu, paslaugos vis labiau keliasi į internetinę erdvę, kuriasi paslaugų internetas. Ilgą laiką Lietuvoje paslaugos internete nebuvo labai populiarios, tačiau jau įgavo pasitikėjimą. Populiarėjant paslaugoms turi pasitempti paslaugų kūrėjai ir tiekėjai. Jie stengiasi siūlyti kokybiškas ir patrauklias paslaugas. Antrosios kartos paslaugų žiniatinklį tuoj papildys semantikos įvedimas – trečios kartos, semantinis žiniatinklis. Semantinio žiniatinklio ir semantinių web servisų sąvokos labai svarbios interneto vystymosi raidoje. Semantinis žiniatinklis kardinaliai pakeis žiniatinklio bei paslaugų internete supratimą. Projektuojama sistema puikiai atitinką pokyčius ir numatomą ateitį paslaugų interneto verslo sektoriuje. Semantiniai web servisai gali būti pritaikomi tiek galutiniams vartotojams tiek verslo poreikiams. Sistema gali būti naudojama versle, panaudojant sistemos išvedimo rezultatus kitiems verslo procesams kaip įvedimo duomenis. Pagrindiniai darbo tikslai – remiantis ankstesniuose tiriamuosiuose darbuose įgyta patirtimi išanalizuoti Lietuvos elektroninio verslo rinką, išanalizuoti semantinių web servisų aplinką, kūrimo įrankius, suprojektuoti semantinio web serviso prototipą, bei pabrėžti jo naudą ir konkurencinio pranašumo įgijimo galimybes. / Information technologies are developing very fast, services are moving to the internet. For a long time online services in the Lithuania hasn’t been very popular but now are quite popular. The popularity of services makes developers and providers to strive. They are trying to offer high quality and great services. The second generation web will be soon complemented with the semantic – the third generation semantic web. In evolution of the internet, semantic web and semantic web service definitions are very important. Semantic web will dramatically change the understanding of web and the services on the Internet. This system is well suited to the expected future changes for services on the Internet in the business sector. The semantic web services can be applied to end users and business needs. The system output can be used for other business processes like data entry. Main goals of my job – to adapt the experience from previous jobs about semantic web technologies, analyze Lithuanian e-business market, the semantic web services environment, tools for services creation, design a semantic web service prototype and highlight competitive advantage opportunities.
279

Association Rule Interactive Post-processing using Rule Schemas and Ontologies - ARIPSO

Marinica, Claudia 26 October 2010 (has links) (PDF)
This thesis is concerned with the merging of two active research domains: Knowledge Discovery in Databases (KDD), more precisely the Association Rule Mining technique, and Knowledge Engineering (KE) with a main interest in knowledge representation languages developed around the Semantic Web. In Data Mining, the usefulness of association rule technique is strongly limited by the huge amount and the low quality of delivered rules. Experiments show that rules become almost impossible to use when their number exceeds 100. At the same time, nuggets are often represented by those rare (low support) unexpected association rules which are surprising to the user. Unfortunately, the lower the support is, the larger the volume of rules becomes. Thus, it is crucial to help the decision maker with an efficient technique to reduce the number of rules. To overcome this drawback, several methods have been proposed in the literature such as itemset concise representations, redundancy reduction, filtering, ranking and post-processing. Even though rule interestingness strongly depends on user knowledge and goals, most of the existing methods are generally based on data structure. For instance, if the user looks for unexpected rules, all the already known rules should be pruned. Or, if the user wants to focus on specific family of rules, only this subset of rules should be selected. In this context, we address two main issues: the integration of user knowledge in the discovery process and the interactivity with the user. The first issue requires defining an adapted formalism to express user knowledge with accuracy and flexibility such as ontologies in the Semantic Web. Second, the interactivity with the user allows a more iterative mining process where the user can successively test different hypotheses or preferences and focus on interesting rules. The main contributions of this work can be summarized as follows: (i) A model to represent user knowledge. First, we propose a new rule-like formalism, called Rule Schema, which allows the user to define his/her expectations regarding the rules through ontology concepts. Second, ontologies allow the user to express his/her domain knowledge by means of a high semantic model. Last, the user can choose among a set of Operators for interactive processing the one to be applied over each Rule Schema (i.e. pruning, conforming, unexpectedness, . . . ). (ii) A new post-processing approach, called ARIPSO (Association Rule Interactive Post-processing using rule Schemas and Ontologies), which helps the user to reduce the volume of the discovered rules and to improve their quality. It consists in an interactive process integrating user knowledge and expectations by means of the proposed model. At each step of ARIPSO, the interactive loop allows the user to change the provided information and to reiterate the post-processing phase which produces new results. (iii) The implementation in post-processing of the proposed approach. The developed tool is complete and operational, and it implements all the functionalities described in the approach. Also, it makes the connection between different elements like the set of rules and rule schemas stored in PMML/XML files, and the ontologies stored in OWL files and inferred by the Pellet reasoner. (iv) An adapted implementation without post-processing, called ARLIUS (Association Rule Local mining Interactive Using rule Schemas), consisting in an interactive local mining process guided by the user. It allows the user to focus on interesting rules without the necessity to extract all of them, and without minimum support limit. In this way, the user may explore the rule space incrementally, a small amount at each step, starting from his/her own expectations and discovering their related rules. (v) The experimental study analyzing the approach efficiency and the discovered rule quality. For this purpose, we used a real-life and large questionnaire database concerning customer satisfaction. For ARIPSO, the experimentation was carried out in complete cooperation with the domain expert. For different scenarios, from an input set of nearly 400 thousand association rules, ARIPSO filtered between 3 and 200 rules validated by the expert. Clearly, ARIPSO allows the user to significantly and efficiently reduce the input rule set. For ARLIUS, we experimented different scenarios over the same questionnaire database and we obtained reduced sets of rules (less than 100) with very low support.
280

Adaptable metadata creation for the Web of Data

Enoksson, Fredrik January 2014 (has links)
One approach to manage collections is to create data about the things in it. This descriptive data is called metadata, and this term is in this thesis used as a collective noun, i.e no plural form exists. A library is a typical example of an organization that uses metadata, to manage a collection of books. The metadata about a book describes certain attributes of it, for example who the author is. Metadata also provides possibilities for a person to judge if a book is interesting without having to deal with the book itself. The metadata of the things in a collection is a representation of the collection that is easier to deal with than the collection itself. Nowadays metadata is often managed in computer-based systems that enable search possibilities and sorting of search results according to different principles. Metadata can be created both by computers and humans. This thesis will deal with certain aspects of the human activity of creating metadata and includes an explorative study of this activity. The increased amount of public information that is produced is also required to be easily accessible and therefore the situation when metadata is a part of the Semantic Web has been considered an important part of this thesis. This situation is also referred to as the Web of Data or Linked Data. With the Web of Data, metadata records living in isolation from each other can now be linked together over the web. This will probably change what kind of metadata that is being created, but also how it is being created. This thesis describes the construction and use of a framework called Annotation Profiles, a set of artifacts developed to enable an adaptable metadata creation environment with respect to what metadata that can be created. The main artifact is the Annotation Profile Model (APM), a model that holds enough information for a software application to generate a customized metadata editor from it. An instance of this model is called an annotation profile, that can be seen as a configuration for metadata editors. Changes to what metadata can be edited in a metadata editor can be done without modifying the code of the application. Two code libraries that implement the APM have been developed and have been evaluated both internally within the research group where they were developed, but also externally via interviews with software developers that have used one of the code-libraries. Another artifact presented is a protocol for how RDF metadata can be remotely updated when metadata is edited through a metadata editor. It is also described how the APM opens up possibilities for end user development and this is one of the avenues of pursuit in future research related to the APM. / <p>QC 20141028</p>

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