A Framework for Semantic Interoperability for Distributed Geospatial Repositories

Interoperable access of geospatial information across disparate geospatial applications has become essential. Geospatial data are highly heterogeneous -- the heterogeneity arises both at the syntactic and semantic levels. Finding and accessing appropriate data in such a distributed environment is an important research issue. The paper proposes a methodology for interoperable access of geospatial information based on Open Geospatial Consortium (OGC) specified standards. An architecture for integrating diverse geospatial data repositories has been proposed using service-based methodology. The semantic issues for discovery and retrieval of geospatial data over distributed geospatial services have also been proposed in the paper. The proposed architecture utilizes the ontological concepts for service description and subsequent discovery of services. An approach for semantic similarity assessment of geospatial services has been discussed

Is question answering fit for the Semantic Web? A survey

With the recent rapid growth of the Semantic Web (SW), the processes of searching and querying content that is both massive in scale and heterogeneous have become increasingly challenging. User-friendly interfaces, which can support end users in querying and exploring this novel and diverse, structured information space, are needed to make the vision of the SW a reality. We present a survey on ontology-based Question Answering (QA), which has emerged in recent years to exploit the opportunities offered by structured semantic information on the Web. First, we provide a comprehensive perspective by analyzing the general background and history of the QA research field, from influential works from the artificial intelligence and database communities developed in the 70s and later decades, through open domain QA stimulated by the QA track in TREC since 1999, to the latest commercial semantic QA solutions, before tacking the current state of the art in open userfriendly interfaces for the SW. Second, we examine the potential of this technology to go beyond the current state of the art to support end-users in reusing and querying the SW content. We conclude our review with an outlook for this novel research area, focusing in particular on the R&D directions that need to be pursued to realize the goal of efficient and competent retrieval and integration of answers from large scale, heterogeneous, and continuously evolving semantic sources

Ontology based data warehousing for mining of heterogeneous and multidimensional data sources

Heterogeneous and multidimensional big-data sources are virtually prevalent in all business environments. System and data analysts are unable to fast-track and access big-data sources. A robust and versatile data warehousing system is developed, integrating domain ontologies from multidimensional data sources. For example, petroleum digital ecosystems and digital oil field solutions, derived from big-data petroleum (information) systems, are in increasing demand in multibillion dollar resource businesses worldwide. This work is recognized by Industrial Electronic Society of IEEE and appeared in more than 50 international conference proceedings and journals

Making Distant Futures: Implementing Geological Disposal of Nuclear Waste in the UK and Finland

This thesis explores the making of distant futures through two nuclear waste disposal projects. Geological disposal of nuclear waste (GD) has enjoyed a technopolitical consensus for decades as the best available method for the long-term management of hazardous radioactive material, yet, to date, no geological repository facilities exist anywhere in the world. These ‘disposal facilities’ are expected to seclude nuclear waste from the environment for up to one million years, raising challenges for technical knowledge production, policy implementation and public expectations. Examining the proposed implementation of GD in the UK and Finland, this thesis focuses on the ways in which the management of nuclear waste is crafted in the present day and projected on, million of years into the future, as necessitated by the waste half- lives and as demanded by regulatory practice. In exploring these two national contexts, the thesis traces how knowledge is made about distant futures that exist beyond contemporary knowledge making capacity. As a contribution to limited ethnographic discussion on nuclear waste matters, the making of distant nuclear futures is examined in spaces that have been overlooked in sociological literatures on GD e.g. materials science laboratories. The thesis draws from actor-network approaches, sociology of time and feminist STS literature to develop a ‘comparative-conversationalist’ framework. This approach enabled the comparison of wildly different cases by bringing them into conversation rather than direct comparison with each other. Based on participant-observations in two university research labs; interviews with civil servants, university researchers, technical consultants, regulators and industry representatives; and documentary analysis, I trace practices through which the future is made safe, and, nuclear wastes crafted as manageable. The thesis will demonstrate how future making around nuclear waste varies over time and space. I propose that, because of the very distant future that GD concerns, we should discuss the safety aspects of GD and the ability of disposal facilities to contain wastes as ‘real unrealised present possibilities’. Towards this, I develop the notion of contain-ability. Contain-ability directs attention towards the relational makings of safety in the present, and the uncertainty of containment in the very distant future. It underlines safety as an emergent feature rather than an inherent property of disposal concepts and facilities achieved by engineers. 3 Overall then, the thesis demonstrates that a distant nuclear future is a crafted through situated makings that depend on available sociotechnical conditions, including: geological environments; the scale and complexity of nuclear industries and waste inventories; available financial resources and cultural reserves; and imaginations of wastes, nuclear futures and pasts. The successes and failures of policies for the implementation of GD cannot be construed simply through public acceptance or opposition arguments and more attention needs to be directed to the contingencies of scientific knowledge production and future making

Deconstructing U.S. Army Maps of Korea: A Case Study for Rethinking Historical Environmental Data

At a time when the natural world and global climate are experiencing extreme changes at unprecedented speeds, understanding these environmental changes over time is more important than ever. With advances in remote sensing technology, large amounts of information about the natural world are becoming more accessible than ever before; however, satellite-collected data are only available from 1984 onwards. To understand how land use has changed on longer timescales, researchers have turned towards archival maps as a data source. Archival maps are a rich source of environmental information; however, they are often saturated with complicated colonial histories. Maps, more so than other historical materials, can hide behind the veneer of objectivity and thus escape important interrogation. As methods that utilize archival maps become more popular, the need to critically analyze the historical and social contexts of the maps becomes even stronger. This thesis argues for a rethinking of historical environmental data through a case study of U.S. Military Maps of Korea from 1945-1954. By providing appropriate historical and social context, three maps of Seoul are deconstructed, thereby illuminating their fallibility as objective environmental sources. This case study ultimately encourages scholars to engage with environmental history more critically and think beyond the analogues dictated by current technology

Reusing Ontologies to Enrich Semantically User Content in Web2.0: A Case Study on Folksonomies

Semantic Web and Web2.0 emerged during the past decade promising to achieve new frontiers for the Web. On the one hand, the Semantic Web is an interlinked web of data, supported by ontological semantics and allowing for intelligent applications such as semantic search and integration of heterogeneous content across systems and applications. On the other hand, Web2.0 represents the new technologies and paradigms that revolutionised the user engagement in content creation and introduced novel means towards social interaction. Bridging the gap between Web2.0 and the Semantic Web has been proposed as a means to better manage and interact with the large amounts of user contributed content, which is a new challenge for Web2.0. This thesis focuses on a popular paradigm of Web2.0, folksonomies. In particular, we investigate the semantic enrichment of folksonomy tagspaces by reusing ontologies available in the Semantic Web. We identify the need for methods that automatically apply semantic descriptions to user generated content without requiring user intervention or alteration of the current tagging paradigm. We use an iterative approach in order to identify the characteristics of folksonomies and the attributes of knowledge sources that influence the semantic enrichment of tagspaces. We build on the results of our experimental studies to implement a folksonomy enrichment algorithm, that given an input tagspace, automatically creates a semantic structure that describes the meaning and relations of tags. We introduce measures for the evaluation of enriched tagspaces and finally, we propose a search algorithm that exploits the semantic structures to improve folksonomy search

{YAGO}2: A Spatially and Temporally Enhanced Knowledge Base from {Wikipedia}

We present YAGO2, an extension of the YAGO knowledge base, in which entities, facts, and events are anchored in both time and space. YAGO2 is built automatically from Wikipedia, GeoNames, and WordNet. It contains 80 million facts about 9.8 million entities. Human evaluation confirmed an accuracy of 95\% of the facts in YAGO2. In this paper, we present the extraction methodology, the integration of the spatio-temporal dimension, and our knowledge representation SPOTL, an extension of the original SPO-triple model to time and space

Methods for creating and using geospatio-temporal semantic web

This dissertation discusses the problems and the methods of creating and using ontologies in the area of digital cultural heritage. One of the problems is that content annotations in semantic cultural heritage portals commonly make spatiotemporal references to historical regions and places using names whose meanings are different in different times. For example, historical administrational regions such as countries, municipalities, and cities have been renamed, merged together, split into parts, and annexed or moved to and from other regions. The contribution of this dissertation to this problem is to develop methods which can be used to model, produce and utilize geospatio-temporal ontologies. The resources in geospatio-temporal ontologies can be used as annotation terms for describing content, and also for seeking information. The main point of this dissertation is to describe schemas, models and methods that produce and utilize a geospatio-temporal ontology. The schemas and the models are used as inputs for the methods. These methods generate identifiers for spatio-temporal instances, and also relationships between them. In this work, historical Finnish municipalities were modeled and geospatio-temporal descriptions for them created from a filled-up schema. Methods enriched the models by creating geospatio-temporal relationships between these temporal municipalities. The resulting collection of models are referred to as the Finnish Spatio-temporal Ontology (Suomen ajallinen paikkaontologia, SAPO). Specific relationships of the geo-spatiotemporal instances provided the basis for novel recommendation, data mining and visualization schemes. The results of the experiments were promising. For example, with the help of the ontology a user has the ability to retrieve also the content annotated to a historic region even if she searches using a contemporary name of the same or partially overlapping region. The work contributes also to modeling and reasoning about imprecise temporal intervals. A set of different measures based on analyzing two fuzzy temporal intervals are presented and evaluated in the work. The use of a combination of different measures for calculating relevance between temporal intervals was found out to perform best