This thesis is part of the knowledge representation domain and modeling of uncertainty in a context of information fusion. The main idea is to use semantic tools and more specifically ontologies, not only to represent the general domain knowledge and observations, but also to represent the uncertainty that sources may introduce in their own observations. We propose to represent these uncertainties and semantic imprecision trough a metaontology (called DS-Ontology) based on the theory of belief functions. The contribution of this work focuses first on the definition of semantic inclusion and intersection operators for ontologies and on which relies the implementation of the theory of belief functions, and secondly on the development of a tool called FusionLab for merging semantic information within ontologies from the previous theorical development. These works have been applied within a European maritime surveillance project.

XML data is often accompanied by type information, usually expressed by some schema language. Sometimes XML data can be related to ontologies defining classes of objects, such classes can also be interpreted as types. Type systems proved to be extremely useful in programming languages, for instance to automatically discover certain kinds of errors. This thesis deals with an XML query language Xcerpt, which originally has no underlying type system nor any provision for taking advantage of existing type information. We provide a type system for Xcerpt; it makes possible type inference and checking type correctness. The system is descriptive: the types associated with Xcerpt constructs are sets of data terms and approximate the semantics of the constructs. A formalism of Type Definitions is adapted to specify such sets. The formalism may be seen as a simplification and abstraction of XML schema languages. The type inference method, which is the core of this work, may be seen as abstract interpretation. A non standard way of assuring termination of fixed point computations is proposed, as standard approaches are too inefficient. The method is proved correct wrt. the formal semantics of Xcerpt. We also present a method for type checking of programs. A success of type checking implies that the program is correct wrt. its type specification. This means that the program produces results of the specified type whenever it is applied to data of the given type. On the other hand, a failure of type checking suggests that the program may be incorrect. Under certain conditions (on the program and on the type specification), the program is actually incorrect whenever the proof attempt fails. A prototype implementation of the type system has been developed and usefulness of the approach is illustrated on example programs. In addition, the thesis outlines possibility of employing semantic types (ontologies) in Xcerpt. Introducing ontology classes into Type Definitions makes possible discovering some errors related to the semantics of data queried by Xcerpt. We also extend Xcerpt with a mechanism of combining XML queries with ontology queries. The approach employs an existing Xcerpt engine and an ontology reasoner; no modifications are required.

There are two significant impedances to the realization of the potential of ontologies. First, many ontology designers lack the necessary background in formal logics to express their intuitions clearly and precisely, resulting in the proliferation of ontologies with low expressivity. Concurrently, developing semantic mappings between existing ontologies is difficult, because much of the semantics is external to the representation. This thesis uses the idea of metaphor to develop architectures for ontology repositories to serve as bottom-up reusable resources. Moreover, an ontology design algorithm has been developed that allows designers to communicate their ideas at the semantic level, simply by generating and vetting models. Finally, a semantic mapping algorithm has been developed that uses an ontology repository to determine the similarities and differences between any number of target ontologies. An ontology for partial orders has been elaborated to demonstrate the proof of concept and populate the first iteration of the repository.

There are two significant impedances to the realization of the potential of ontologies. First, many ontology designers lack the necessary background in formal logics to express their intuitions clearly and precisely, resulting in the proliferation of ontologies with low expressivity. Concurrently, developing semantic mappings between existing ontologies is difficult, because much of the semantics is external to the representation. This thesis uses the idea of metaphor to develop architectures for ontology repositories to serve as bottom-up reusable resources. Moreover, an ontology design algorithm has been developed that allows designers to communicate their ideas at the semantic level, simply by generating and vetting models. Finally, a semantic mapping algorithm has been developed that uses an ontology repository to determine the similarities and differences between any number of target ontologies. An ontology for partial orders has been elaborated to demonstrate the proof of concept and populate the first iteration of the repository.

A web service is a collection of functions that are packaged as a single entity and published to the network for use by other programs. Web services are building blocks for creating open distributed systems, and allow companies and individuals to quickly and cheaply make their digital assets available worldwide. With considerable interoperability, privacy management becomes an inevitable concern of the web services. Companies and individuals should be able to restrict the information available about themselves and specify the use of that information in order to protect their confidentiality. In the thesis, a privacy framework has been designed and implemented in order to prepare and match privacy documents for web services. Privacy documents are prepared based upon message ontologies which describe the input data of web services. Service requestors and providers prepare their own privacy documents which are going to be checked before the web service transaction begins. Privacy content has been derived from the World Wide Web Consortium&rsquo / s Platform for Privacy Preferences specification.

We are rapidly entering a world with an immense amount of services and devices available to humans and machines. This is a promising future, however there are at least two major challenges for using these services and devices: (1) they have to be found and (2) after being found, they have to be selected amongst. A significant difficulty lies in not only finding most available services, but presenting the most useful ones. In most cases, there may be too many found services and devices to select from. Service discovery needs to become more aimed towards humans and less towards machines. The service discovery challenge is especially prevalent in ubiquitous computing. In particular, service and device flux, human overloading, and service relevance are crucial. This thesis addresses the quality of use of services and devices, by introducing a sophisticated discovery model through the use of new layers in service discovery. This model allows use of services and devices when current automated service discovery and selection would be impractical by providing service suggestions based on user activities, domain knowledge, and world knowledge. To explore what happens when such a system is in place, a wizard of oz study was conducted in a command and control setting. To address service discovery in ubiquitous computing new layers and a test platform were developed together with a method for developing and evaluating service discovery systems. The first layer, which we call the Enhanced Traditional Layer (ETL), was studied by developing the ODEN system and including the ETL within it. ODEN extends the traditional, technical service discovery layer by introducing ontology-based semantics and reasoning engines. The second layer, the Relevant Service Discovery Layer, was explored by incorporating it into the MAGUBI system. MAGUBI addresses the human aspects in the challenge of relevant service discovery by employing common-sense models of user activities, domain knowledge, and world knowledge in combination with rule engines.  The RESPONSORIA system provides a web-based evaluation platform with a desktop look and feel. This system explores service discovery in a service-oriented architecture setting. RESPONSORIA addresses a command and control scenario for rescue services where multiple actors and organizations work together at a municipal level. RESPONSORIA was the basis for the wizard of oz evaluation employing rescue services professionals. The result highlighted the importance of service naming and presentation to the user. Furthermore, there is disagreement among users regarding the optimal service recommendation, but the results indicated that good recommendations are valuable and the system can be seen as a partner. / Vi rör oss snabbt in i en värld med en enorm mängd tjänster och enheter som finns tillgängliga för människor och maskiner. Detta är en lovande framtid, men det finns åtminstone två stora utmaningar för att använda dessa tjänster och enheter: (1) de måste hittas och (2) rätt tjänst/enhet måste väljas. En betydande svårighet ligger i att, inte bara finna de mest lättillgängliga tjänsterna och enheterna, men också att presentera de mest användbara sådana. I de flesta fall kan det vara för många tjänster och enheter som hittas för att kunna välja mellan. Upptäckten av tjänster och enheter behöver bli mer anpassad till människor och mindre till maskiner. Denna utmaning är särskilt framträdande i desktopmetaforens efterföljare Ubiquitous Computing. (Det vill säga en form av interaktion med datorer som blivit integrerad i aktiviteter och objekt i omgivningen.) Framförallt tjänster och enheters uppdykande och försvinnande, mänsklig överbelastning och tjänstens relevans är avgörande utmaningar. Denna avhandling behandlar kvaliteten på användningen av tjänster och enheter, genom att införa en sofistikerad upptäcktsmodell med hjälp av nya lager i tjänsteupptäcktsprocessen. Denna modell tillåter användning av tjänster och enheter när nuvarande upptäcktsprocess och urval av dessa skulle vara opraktiskt, genom att ge förslag baserat på användarnas aktiviteter, domänkunskap och omvärldskunskap. För att utforska vad som händer när ett sådant system är på plats, gjordes ett så kallat Wizard of Oz experiment i ledningscentralen på en brandstation. (Ett Wizard Of Oz experiment är ett experiment där användaren tror att de interagerar med en dator, men i själva verket är det en människa som agerar dator.) För att hantera tjänste- och enhetsupptäckt i Ubiquitous Computing utvecklades nya lager och en testplattform tillsammans med en metod för att utveckla och utvärdera system för tjänste- och enhetsupptäckt. Det första lagret, som vi kallar Förbättrat Traditionellt Lager (FTL), studerades genom att utveckla ODEN och inkludera FTL i den. ODEN utökar det traditionella, datororienterade tjänste- och enhetsupptäcktslagret genom att införa en ontologibaserad semantik och en logisk regelmotor. Det andra skiktet, som vi kallar Relevant Tjänst Lager, undersöktes genom att införliva det i systemet MAGUBI. MAGUBI tar sig an de mänskliga aspekterna i den utmaning som vi benämner relevant tjänste- och enhetsupptäckt, genom att använda modeller av användarnas aktiviteter, domänkunskap och kunskap om världen i kombination med regelmotorer. RESPONSORIA är en webbaserad plattform med desktoputseende och desktopkänsla, och är ett system för utvärdering av ovanstående utmaning tillsammans med de tidigare systemen. Detta system utforskar tjänste- och enhetsupptäckt i ett tjänsteorienterat scenario. RESPONSORIA tar ett ledningsscenario för räddningstjänst där flera aktörer och organisationer arbetar tillsammans på en kommunal nivå. RESPONSORIA låg till grund för ett Wizard of Oz experiment där experimentdeltagarna var professionella räddningsledare. Resultatet underströk vikten av namngivning av tjänster och enheter samt hur dessa presenteras för användaren. Dessutom finns det oenighet bland användare om vad som är den optimala service-/enhets-rekommendationen, men resultaten visar att goda rekommendationer är värdefulla och systemet kan ses som en partner.

Thesis (M.S.)--State University of New York at Binghamton, Department of Computer Science, Thomas J. Watson School of Engineering and Applied Science, 2006. / Includes bibliographical references.

Thesis (M.S.)--State University of New York at Binghamton, Department of Computer Science, Thomas J. Watson School of Engineering and Applied Science, 2007. / Includes bibliographical references.

Thesis (Ph. D.)--University of Washington, 2008. / Vita. Includes bibliographical references (p. 128-132).

Zugl.: Barcelona, Universidad Politécnica de Cataluña., Diss., 2007 / Hergestellt on demand