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A New Approach for Indoor Navigation Using Semantic Webtechnologies and Augmented Reality

Indoor navigation is an important research topic nowadays. The complexity of larger buildings, supermarkets, museums, etc. makes it necessary to use applications which can facilitate the orientation. While for outdoor navigation already exist tried and tested solutions, but few reliable ones are available for indoor navigation. In this paper we investigate the possible technologies for indoor navigation. Then, we present a general, cost effective system as a solution. This system uses the advantages of semantic web to store data and to compute the possible paths as well. Furthermore it uses Augmented Reality techniques and map view to provide interaction with the users. We made a prototype based on client-server architecture. The server runs in a cloud and provides the appropriate data to the client, which can be a smartphone or a tablet with Android operation system.

Geodint: Towards Semantic Web-Based Geographic Data Integration

The main objective of data integration is to unify data from different sources and to provide a unified view to the users. The integration of heterogeneous data has some benefits both for companies and for research. However, finding the common schema and filtering the same element becomes difficult due to the heterogeneity. In this paper, a system is presented that is able to integrate geographic data from different sources using Semantic Web technologies. The problems that appear during the integration are also handled by the system. An ontology has been developed that stores the common attributes that are given after schema matching. To filter the inconsistent and duplicate elements, clustering and string similarity metrics have been used. The data given after integrating can be used among others for touristic purposes, for example it could provide data to an augmented reality browser.

A Semantically Enriched Augmented Reality Browser

Owing to the remarkable advancement of smartphones, Augmented Reality applications have become part of everyday life. Augmented Reality browsers are the most commonly used among these applications. The users can search and display interesting places from the physical environment surrounding them by means of these browsers. Some of the most popular AR browsers use only one data source and the openly available datasets are not used. In contrast, the main objective of Linked Open Data community project is to link knowledge from different data sources. This pursuit makes it easier to retrieval information, among others. In this paper, an Augmented Reality browser was presented. Information derived from Linked Open Data was used by the browser as data source. Due to this, the system is able to handle more data sources.

An Ontology-Based Augmented Reality Application Exploring Contextual Data of Cultural Heritage Sites

In this study, we present a novel Augmented Reality (AR) application for providing contextual information of cultural heritage sites. Whereas most location-based AR systems are designed to show simple information on a Point of Interest (POI) in the real world, the suggested application offers information related to various cultural heritages including tangible and intangible heritages linked to the POI. is is accomplished by a cultural heritage ontology that aggregates heterogeneous data and reorganizes information in themes and relationships. The users can browse information such as the person who created the POI and events that took place at the location as separate entities. We implemented the application for Injeongjeon and the vicinity of Changdeokgung palace and conducted user studies to determine how people explore and consume contextual information at the heritage site. We provide directions that will be useful for designing information to support heritage site visiting, and discuss how the AR technology could improve the application.

mSWB: Towards a Mobile Semantic Web Browser

An enormous amount of information stored in semantic format has become available nowadays. In order to browse this huge data, the development of different browsers has become necessary. Today, many browsers available, but these are typically desktop applications. Vast knowledge bases have been created by means of linking the different public datasets. The efficient query of these data is a difficult problem. The currently available browsers typically do not allow browsing over the federated datasets, generally displaying only the information of a specified dataset. In this paper a mobile semantic web information system is presented, which allows smartphones to browse federated semantic datasets. In addition, the details of data integrator middleware and the Android-based client and the evaluation are described.

Ontology-based mobile augmented reality in cultural heritage sites: information modeling and user study

Augmented reality (AR) has received much attention in the cultural heritage domain as an interactive medium for requesting and accessing information regarding heritage sites. In this study, we developed a mobile AR system based on Semantic Web technology to provide contextual information about cultural heritage sites. Most location-based AR systems are designed to present simple information about a point of interest (POI), but the proposed system offers information related to various aspects of cultural heritage, both tangible and intangible, linked to the POI. This is achieved via an information modeling framework where a cultural heritage ontology is used to aggregate heterogeneous data and semantically connect them with each other. We extracted cultural heritage data from five web databases and modeled contextual information for a target heritage site (Injeongjeon Hall and its vicinity in Changdeokgung Palace in South Korea) using the selected ontology. We then implemented a mobile AR application and conducted a user study to assess the learning and engagement impacts of the proposed system. We found that the application provides an agreeable user experience in terms of its affective, cognitive, and operative features. The results of our analysis showed that specific usage patterns were significant with regard to learning outcomes. Finally, we explored how the study’s key findings can provide practical design guidance for system designers to enhance mobile AR information systems for heritage sites, and to show system designers how to support particular usage patterns in order to accommodate specific user experiences better.

The Design and Implementation of Semantic Web-Based Architecture for Augmented Reality Browser

Due to the proliferation of smartphones, Augmented Reality applications have become more widespread nowadays. Augmented Reality browsers have especially enjoyed wide popularity within these applications. The physical environment could be extended by location-aware additional information using these browsers. At present, typically a specific data source is used by the current Augmented Reality browsers, even if there is an enormous amount of available data sources. The Semantic Web could help to bridge this problem. The goal of this work is to combine Augmented Reality and Semantic Web technologies in order to enhance the existing mobile Augmented Reality browsers using Semantic Web technologies. For this purpose, we utilize the advantages of the Semantic Web technologies such as data integration, unified data model as well as publicly available semantic data sources, among other things.

Augmented Reality Supported by Semantic Web Technologies

Augmented Reality applications are more and more widely used nowadays. With help of it the real physical environment could be extended by computer generated virtual elements. These virtual elements can be for example important context-aware information. With Semantic Web it is possible among others to handle data which come from heterogeneous sources. As a result we have the opportunity to combine Semantic Web and Augmented Reality utilizing the benefits of combination of these technologies. The obtained system may be suitable for daily use with wide range of applications in field of tourism, entertainment, navigation, ambient assisted living, etc. The purpose of my research is to develop a prototype of general framework which satisfies the above criteria.

Parallel enumeration of degree sequences of simple graphs II

Abstract In the paper we report on the parallel enumeration of the degree sequences (their number is denoted by G(n)) and zerofree degree sequences (their number is denoted by (Gz(n)) of simple graphs on n = 30 and n = 31 vertices. Among others we obtained that the number of zerofree degree sequences of graphs on n = 30 vertices is Gz(30) = 5 876 236 938 019 300 and on n = 31 vertices is Gz(31) = 22 974 847 474 172 374. Due to Corollary 21 in [52] these results give the number of degree sequences of simple graphs on 30 and 31 vertices.

Experimental evaluation of some geodata management systems

Several Geographic Information Systems have become available nowadays. As a result, the most widely used, different types of databases (relational, semantic, NoSQL) allow efficient management of spatial data types. These spatial functions are also required by Augmented Reality browsers in order to handle Points of Interest that have some spatial attributes. In the past few years, some studies on database evaluation and benchmarking applications have been published. However, we have not found one that would be optimized for the case of Augmented Reality browsers. In this paper, a benchmarking tool and the evaluation of spatial properties of the most popular relational and semantic databases is presented.