Abstract Infrastructures like transportation, power, and pipeline networks which are characterized by a spatial embedding are known as spatial networks. Spatial networks are ubiquitous in our everyday life and used in transport, navigation, and city planning as well as in Geographical Information Systems (GIS) and other geo-spatial applications. The largely increasing amount of generated data about spatial networks can only be... Infrastructures like transportation, power, and pipeline networks which are characterized by a spatial embedding are known as spatial networks. Spatial networks are ubiquitous in our everyday life and used in transport, navigation, and city planning as well as in Geographical Information Systems (GIS) and other geo-spatial applications. The largely increasing amount of generated data about spatial networks can only be efficiently stored and analyzed in a database system. However database support for large spatial networks in order to represent, store, query, and manipulate them is rare. This article aims to provide a conceptual, abstract, and formal model of spatial networks, called Spatial Network Algebra (SNA). It includes data types, operations, and predicates and serves as a specifification for their later implementation in spatial database systems and GIS. Finally, we show how our spatial network concepts can be embedded into an SQL-like query language. Read More Read Less

Abstract Exploring the topology of a region object requires the mathematical study of its geometric properties that are preserved under deformations. A moving region whose location and extent change over time can undergo several topological changes such as the splitting of a region or the formation of a hole. The study of this kind of changes is important in many applications,... Exploring the topology of a region object requires the mathematical study of its geometric properties that are preserved under deformations. A moving region whose location and extent change over time can undergo several topological changes such as the splitting of a region or the formation of a hole. The study of this kind of changes is important in many applications, e.g., for the topology control of wireless sensor networks and the processing of animation images in multimedia applications. Since we often lack the ability of capturing the location, extent, and shape changes of a moving region during its lifespan, it is challenging to detect these changes. Further, for a complex moving region containing multiple components, it is difficult to determine which component before a change corresponds to which component after the change. In this article, we propose a model pursuing a three-phase strategy to determine the topological changes of a complex moving region represented by a sequence of snapshots called observations. The fifirst phase partitions the observations into several evaluation units. The second phase uniquely maps each unit before the change to exactly one unit after the change. The third phase interprets the topological changes by integrating all basic topological changes from the evaluation units. We also show the detailed algorithms of this three-phase strategy which turn out to be efficient. Finally, a case study illustrates our concepts. Read More Read Less

Abstract In this paper we investigated the levels of addiction and personal data disclosure within Massively Multiplayer Online Role Playing Game environments (MMORPG’s). The study made use of an online survey, a combination of a six point behavioural addiction framework, Self Determination Theory and Impression Management theory to assess addictive behaviour and consequential data disclosure amongst a sample of 188 Singaporean... In this paper we investigated the levels of addiction and personal data disclosure within Massively Multiplayer Online Role Playing Game environments (MMORPG’s). The study made use of an online survey, a combination of a six point behavioural addiction framework, Self Determination Theory and Impression Management theory to assess addictive behaviour and consequential data disclosure amongst a sample of 188 Singaporean based MMORPG gamers. These findings were juxtaposed with results of a previous study which investigated MMORPG addiction and data disclosure amongst 357 European online gamers to facilitate a cultural comparison [8]. Results found that pathological gaming addiction had a direct effect on levels of personal and sensitive data disclosure and participants who were disclosing high amounts of data were considered more vulnerable to exploitation and predation. In addition, the Singaporean sample exhibited similar levels of addiction yet marginally lower levels of data disclosure compared to their European counterparts. Read More Read Less

Abstract Table has been recognized as a simply and widely used data representation scheme. Each table alone typically contains rich and useful information which is valuable for many applications such as information retrieval, question-answering and etc. While all table formats can simply be parsed by human, this parsing is difficult for computer, prohibiting such applications to be done in an automatic... Table has been recognized as a simply and widely used data representation scheme. Each table alone typically contains rich and useful information which is valuable for many applications such as information retrieval, question-answering and etc. While all table formats can simply be parsed by human, this parsing is difficult for computer, prohibiting such applications to be done in an automatic manner. In this paper, we thus propose the comprehensive and novel table interpreta- tion technique, namely tInterpreter. Essentially, it transforms a table into its corresponding horizontal 1-dimensional tables. To achieve this, the underlying work is based on (i) the similarity of two given cells with respect to the data type and the semantic correspondence concerns; (ii) the discovery for the boundary of a primitive table residing in a composite table; (iii) the identifification of the attribute-value relationship and the value association of cells; and (iv) the integration of two pieces of similar or dissimilar information. The experimental result showed that the overall effectiveness of tInterpreter was higher than Chen,Tengli and Kim. Read More Read Less