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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

Utökning av LaTeX med stöd för semantisk information

Löfqvist, Ronny January 2007 (has links)
<p>The semantic web is a vision of the Internets future, there machines and humans can understand the same information. To make this possible, documents have to be provided with metadata in a general language. W3C has created Web Ontology Language (owl) for this purpose.</p><p>This report present the creation of a LaTeX package, which makes it possible to include metadata in pdf files. It also presents how you can create annotations, which are bound to the metadata that's been generated. With the help of this package it's easy to create pdf documents with automatically generated metadata and annotations.</p>
82

Context Mediation in the Semantic Web: Handling OWL Ontology and Data Disparity through Context Interchange

Tan, Philip Eik Yeow, Tan, Kian Lee, Madnick, Stuart E. 01 1900 (has links)
The COntext INterchange (COIN) strategy is an approach to solving the problem of interoperability of semantically heterogeneous data sources through context mediation. COIN has used its own notation and syntax for representing ontologies. More recently, the OWL Web Ontology Language is becoming established as the W3C recommended ontology language. We propose the use of the COIN strategy to solve context disparity and ontology interoperability problems in the emerging Semantic Web – both at the ontology level and at the data level. In conjunction with this, we propose a version of the COIN ontology model that uses OWL and the emerging rules interchange language, RuleML. / Singapore-MIT Alliance (SMA)
83

Habitat associations of cavity-nesting owls in the Sierra Nevada

Groce, Julie Elizabeth 15 May 2009 (has links)
Several species of small, cavity-nesting owls occur in the Sierra Nevada, including in areas impacted by human activities. The owls typically use standing dead trees (snags) for nest sites. Although descriptive studies exist regarding habitats associations around nest and roost sites, few studies have examined habitat associations at larger spatial scales or relative to certain snag characteristics (e.g., density, decay class). To improve our understanding of the habitat associations of these owls, I compared habitat characteristics at 2 spatial scales around areas of owl detection and non-detection. I also examined distances between conspecifics and heterospecifics to determine if clustering of conspecifics or avoidance of predators occurred. I conducted owl broadcast surveys and snag sampling during the spring and summer of 2006 and 2007 in the Lake Tahoe Basin of central Sierra Nevada. I measured additional habitat variables (e.g., vegetation cover, distance to roadways) from pre-existing geographical information system layers. I used stepwise logistic regression to ascertain which variables were influential in predicting owl occurrence. The northern saw-whet owl (Aegolius acadicus) was the only species detected in sufficient numbers for statistical analysis, with a detection probability of 0.25. I detected saw-whets in a wide range of conditions and it appeared that few factors influenced their distribution in the basin. Areas dominated by white fir, however, were correlated with the absence of saw-whets at both the macrohabitat and microhabitat scales. White fir-dominated areas tend to occur on the west side of the basin and it is possible white fir was acting as a proxy for other factors not measured in this study, such as microclimate conditions or prey availability. I was also more likely to find a saw-whet within 1000 m of another saw-whet than within 1000 m of a non-use point, indicating clustering of conspecifics in the basin. While it appears saw-whet needs are being met in the basin, restoration projects are ongoing to decrease both the number of snags and relative abundance of white fir. Continued monitoring of the species is essential to understand potential effects of restoration activities. Suggestions are provided for appropriate timing and effort of future surveys.
84

Maintaining Integrity Constraints in Semantic Web

Fang, Ming 10 May 2013 (has links)
As an expressive knowledge representation language for Semantic Web, Web Ontology Language (OWL) plays an important role in areas like science and commerce. The problem of maintaining integrity constraints arises because OWL employs the Open World Assumption (OWA) as well as the Non-Unique Name Assumption (NUNA). These assumptions are typically suitable for representing knowledge distributed across the Web, where the complete knowledge about a domain cannot be assumed, but make it challenging to use OWL itself for closed world integrity constraint validation. Integrity constraints (ICs) on ontologies have to be enforced; otherwise conflicting results would be derivable from the same knowledge base (KB). The current trends of incorporating ICs into OWL are based on its query language SPARQL, alternative semantics, or logic programming. These methods usually suffer from limited types of constraints they can handle, and/or inherited computational expensiveness. This dissertation presents a comprehensive and efficient approach to maintaining integrity constraints. The design enforces data consistency throughout the OWL life cycle, including the processes of OWL generation, maintenance, and interactions with other ontologies. For OWL generation, the Paraconsistent model is used to maintain integrity constraints during the relational database to OWL translation process. Then a new rule-based language with set extension is introduced as a platform to allow users to specify constraints, along with a demonstration of 18 commonly used constraints written in this language. In addition, a new constraint maintenance system, called Jena2Drools, is proposed and implemented, to show its effectiveness and efficiency. To further handle inconsistencies among multiple distributed ontologies, this work constructs a framework to break down global constraints into several sub-constraints for efficient parallel validation.
85

Spatial Ontology for the Production Domain of Petroleum Geology

Liadey, Dickson M. 11 May 2012 (has links)
ABSTRACT The availability of useful information for research strongly depends on well structured relationships between consistently defined concepts (terms) in that domain. This can be achieved through ontologies. Ontologies are models of the knowledge of specific domain such as petroleum geology, in a computer understandable format. Knowledge is a collection of facts. Facts are represented by RDF triples (subject-predicate-object). A domain ontology is therefore a collection of many RDF triples, which represent facts of that domain. The SWEET ontologies are upper or top-level ontologies (foundation ontologies) consisting of thousands of very general concepts. These concepts are obtained from of Earth System science and include other related concepts. The work in this thesis deals with scientific knowledge representation in which the SWEET ontologies are extended to include wider, more specific and specialized concepts used in Petroleum Geology. Thus Petroleum Geology knowledge modeling is presented in this thesis.
86

Habitat associations of cavity-nesting owls in the Sierra Nevada

Groce, Julie Elizabeth 15 May 2009 (has links)
Several species of small, cavity-nesting owls occur in the Sierra Nevada, including in areas impacted by human activities. The owls typically use standing dead trees (snags) for nest sites. Although descriptive studies exist regarding habitats associations around nest and roost sites, few studies have examined habitat associations at larger spatial scales or relative to certain snag characteristics (e.g., density, decay class). To improve our understanding of the habitat associations of these owls, I compared habitat characteristics at 2 spatial scales around areas of owl detection and non-detection. I also examined distances between conspecifics and heterospecifics to determine if clustering of conspecifics or avoidance of predators occurred. I conducted owl broadcast surveys and snag sampling during the spring and summer of 2006 and 2007 in the Lake Tahoe Basin of central Sierra Nevada. I measured additional habitat variables (e.g., vegetation cover, distance to roadways) from pre-existing geographical information system layers. I used stepwise logistic regression to ascertain which variables were influential in predicting owl occurrence. The northern saw-whet owl (Aegolius acadicus) was the only species detected in sufficient numbers for statistical analysis, with a detection probability of 0.25. I detected saw-whets in a wide range of conditions and it appeared that few factors influenced their distribution in the basin. Areas dominated by white fir, however, were correlated with the absence of saw-whets at both the macrohabitat and microhabitat scales. White fir-dominated areas tend to occur on the west side of the basin and it is possible white fir was acting as a proxy for other factors not measured in this study, such as microclimate conditions or prey availability. I was also more likely to find a saw-whet within 1000 m of another saw-whet than within 1000 m of a non-use point, indicating clustering of conspecifics in the basin. While it appears saw-whet needs are being met in the basin, restoration projects are ongoing to decrease both the number of snags and relative abundance of white fir. Continued monitoring of the species is essential to understand potential effects of restoration activities. Suggestions are provided for appropriate timing and effort of future surveys.
87

Från luddig verklighet till strikt formalism : Utveckling av en metod för den semantiska webben

Hahne, Fredrik, Lindgren, Åsa January 2005 (has links)
<p>Internet is the world’s largest source of information, and it is expanding every day. It is possible to find all kind of information as long as you know how and where to look for it, but still it is only the words itself that are searched for. We have with this essay tried to find an approach that makes it possible to give the word a meaning or a context.</p><p>We have, as a starting point used the Socrates method, which is a method that breaks down texts into its smallest elements and forms activities. We have redone these activities to ontologies by forming general and specific descriptions of the activities. The ontologies are meant to create a common language for as well humans as computers, where meaning and context are built in.</p><p>After we have created our ontologies we used Web Ontology Language, OWL, which is the ontology language that is considered being closest to a standard. It has been developed for the semantic web, and that is the ultimate objective of our essay. The semantic web is meant to be an extension of the existing web, and it will include comprehension for computers.</p><p>We have become conscious that the semantic web would be a great improvement for both humans and computers, since it will be a lot easier to find the information you are looking for.</p> / <p>Internet är världens största källa till information och det expanderar för varje dag. Det är möjligt att hitta all slags information om man bara vet vart och hur man ska leta, ändå är det bara orden som eftersöks. Vi har med vår uppsats försökt ta fram ett tillvägagångssätt som gör det möjligt att ge orden en betydelse eller ett sammanhang.</p><p>Som utgångspunkt har vi använt oss av Sokratesmetoden, vilket är en metod som bryter ner texter till dess minsta beståndsdelar, och bildar aktiviteter. Dessa aktiviteter har vi gjort om till ontologier genom att bilda generella och specifika beskrivningar av aktiviteterna. Ontologier är tänkta att skapa ett gemensamt språk för människor och datorer, där betydelse och sammanhang byggs in.</p><p>När vi skapat våra ontologier använde vi oss av Web Ontology Language, OWL, vilket är ett ontologispråk som anses vara närmast en standard. Detta språk har utvecklats för att kunna användas för den semantiska webben, vilken även är slutmålet med vår uppsats. Den semantiska webben är tänkt att utöka den befintliga webben, och ska bygga in förståelse även för datorer.</p><p>Vi har insett att den semantiska webben skulle innebära en stor förbättring för såväl människor som datorer, då det skulle bli enklare att hitta eftersökt information.</p>
88

Migratory behavior of the elf owl (Micrathene whitneyi)

Tellez, Carol Ann Mead, 1940- January 1968 (has links)
No description available.
89

Contaminant Hydrogeology Knowledge Base (CHKb) of Georgia, USA

Sarajlic, Semir 18 December 2013 (has links)
Hydrogeologists collect data through studies that originate from a diverse and growing set of instruments that measure, for example, geochemical constituents of surface and groundwater. Databases store and publish the collected data on the Web, and the volume of data is quickly increasing, which makes accessing data problematic and time consuming for individuals. One way to overcome this problem is to develop ontology to formally and explicitly represent the domain (e.g., contaminant hydrogeology) knowledge. Using OWL and RDF, contaminant hydrogeology ontology (CHO) is developed to manage hydrological spatial data for Georgia, USA. CHO is a conceptual computer model for the contaminant hydrogeology domain in which concepts (e.g. contaminant, aquifer) and their relationships (e.g. pollutes) are formerly and explicitly defined. Cyberinfrastructure for exposing CHO and datasets (i.e., CHKb) as Linked Data on the Web is developed. Cyberinfrastructure consists of storing, managing, querying, and visualizing CHKb that can be accessed from URL: cho.gsu.edu.
90

Exposure of the eastern screech-owl to selected contaminants in apple orchards of southern Quebec

Richards, Ngaio L. January 2003 (has links)
This study examined the exposure of the Eastern Screech-owl (Otus asio) to contaminants in apple orchards of southern Quebec. Using a worstcase scenario approach, secondary exposure to three organophosphorus insecticides, (phosmet, azinphosmethyl and phosalone), two anticoagulant rodenticides, (chlorophacinone and diphacinone), and residues of previously applied organochlorines, particularly DDT and metabolites, was assessed. Exposure to PCBs and trace metals was also considered. Small mammal species preyed upon by Screech-owls were captured in orchards for residue analysis on a continual basis for persistent compounds or after insecticide and rodenticide applications. Beginning in the winter of 2000, 98 nest boxes were constructed and installed in woods inhabited by Screech-owls, adjacent to orchards. These boxes were then repeatedly inspected for pellets and prey remains. Estimated exposure of Screech-owls 0-60 hr post-application was 0.641 mg/kg for phosmet and azinphosmethyl and 0.401 mg/kg for phosalone. Exposure to phosmet at this level may warrant concern. The acute poison zinc phosphide is now the primary means of small mammal control in the study area and the possibility of exposure to anticoagulant rodenticides is diminishing. Observed DDE residues were most elevated in the short-tailed shrew (Blarina brevicauda) and ranged from <1.00 to 26.29 ug/g (wet wt) in whole-body pools. A Screech-owl egg found in a nest box between two orchards may have been thinned by as much as 19.8%, of concern because thinning maintained at 15.0 - 20.0% has been linked to population decline. Only background levels of PCBs and trace metals were detected. Finally, over 950 Screech-owl case files were also obtained from one Canadian and seven United States wildlife rehabilitation facilities and analyzed for evidence that pesticide exposure was an underlying or contributing cause of admissions.

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