107,262 research outputs found

    Routing Protocols for Lossy Wireless Networks

    Get PDF
    Tato prĂĄce zkoumĂĄ vhodnost a poĆŸadavky nĂĄvrhu simulacĂ­ pro simulĂĄtor NS-3 pro pƙípad bezdrĂĄtovĂœch sĂ­tĂ­ pouĆŸĂ­vanĂœch v měƙícĂ­ infrastruktuƙe společnosti Kamstrup. V prĂĄci je popsĂĄn simulĂĄtor NS-3 a je vytvoƙena zĂĄkladnĂ­ implementace dvou protokolĆŻ. Wireless M-Bus jako pƙíklad jednosměrnĂ©ho protokolu pro zaƙízenĂ­ napĂĄjenĂ© z bateriĂ­. Simulace Wireless M-Bus je porovnĂĄna s daty naměƙenĂœmi v reĂĄlnĂ©m systĂ©mu. NS-3 poskytuje flexibilnĂ­ prostƙedĂ­ pro vĂœvoj simulacĂ­ rĆŻznĂœch sĂ­Ć„ovĂœch protokolĆŻ, včetně těch určenĂœch pro sĂ­tě inteligentnĂ­ch měƙidel.This thesis investigates suitability and design constraints of the NS-3 Simulator for simulations of wireless protocols used by Kamstrup metering infrastructure. An overview of NS-3 Simulator is given and preliminary implementations of two protocols are created. Wireless M-Bus as an example of a one-way protocol for battery-powered devices. The simulation of Wireless M-Bus is compared with measurements obtained in a real deployment. NS-3 proves to be a flexible framework for developing simulations of various network protocols, including the ones used for smart metering.

    Moving Object Trajectories Meta-Model And Spatio-Temporal Queries

    Full text link
    In this paper, a general moving object trajectories framework is put forward to allow independent applications processing trajectories data benefit from a high level of interoperability, information sharing as well as an efficient answer for a wide range of complex trajectory queries. Our proposed meta-model is based on ontology and event approach, incorporates existing presentations of trajectory and integrates new patterns like space-time path to describe activities in geographical space-time. We introduce recursive Region of Interest concepts and deal mobile objects trajectories with diverse spatio-temporal sampling protocols and different sensors available that traditional data model alone are incapable for this purpose.Comment: International Journal of Database Management Systems (IJDMS) Vol.4, No.2, April 201

    Forum Session at the First International Conference on Service Oriented Computing (ICSOC03)

    Get PDF
    The First International Conference on Service Oriented Computing (ICSOC) was held in Trento, December 15-18, 2003. The focus of the conference ---Service Oriented Computing (SOC)--- is the new emerging paradigm for distributed computing and e-business processing that has evolved from object-oriented and component computing to enable building agile networks of collaborating business applications distributed within and across organizational boundaries. Of the 181 papers submitted to the ICSOC conference, 10 were selected for the forum session which took place on December the 16th, 2003. The papers were chosen based on their technical quality, originality, relevance to SOC and for their nature of being best suited for a poster presentation or a demonstration. This technical report contains the 10 papers presented during the forum session at the ICSOC conference. In particular, the last two papers in the report ere submitted as industrial papers

    Mobile Online Gaming via Resource Sharing

    Full text link
    Mobile gaming presents a number of main issues which remain open. These are concerned mainly with connectivity, computational capacities, memory and battery constraints. In this paper, we discuss the design of a fully distributed approach for the support of mobile Multiplayer Online Games (MOGs). In mobile environments, several features might be exploited to enable resource sharing among multiple devices / game consoles owned by different mobile users. We show the advantages of trading computing / networking facilities among mobile players. This operation mode opens a wide number of interesting sharing scenarios, thus promoting the deployment of novel mobile online games. In particular, once mobile nodes make their resource available for the community, it becomes possible to distribute the software modules that compose the game engine. This allows to distribute the workload for the game advancement management. We claim that resource sharing is in unison with the idea of ludic activity that is behind MOGs. Hence, such schemes can be profitably employed in these contexts.Comment: Proceedings of 3nd ICST/CREATE-NET Workshop on DIstributed SImulation and Online gaming (DISIO 2012). In conjunction with SIMUTools 2012. Desenzano, Italy, March 2012. ISBN: 978-1-936968-47-

    The combination of spatial access methods and computational geometry in geographic database systems

    Get PDF
    Geographic database systems, known as geographic information systems (GISs) particularly among non-computer scientists, are one of the most important applications of the very active research area named spatial database systems. Consequently following the database approach, a GIS hag to be seamless, i.e. store the complete area of interest (e.g. the whole world) in one database map. For exhibiting acceptable performance a seamless GIS hag to use spatial access methods. Due to the complexity of query and analysis operations on geographic objects, state-of-the-art computational geomeny concepts have to be used in implementing these operations. In this paper, we present GIS operations based on the compuational geomeny technique plane sweep. Specifically, we show how the two ingredients spatial access methods and computational geomeny concepts can be combined fĂŒr improving the performance of GIS operations. The fruitfulness of this combination is based on the fact that spatial access methods efficiently provide the data at the time when computational geomeny algorithms need it fĂŒr processing. Additionally, this combination avoids page faults and facilitates the parallelization of the algorithms.

    Generic unified modelling process for developing semantically rich, dynamic and temporal models

    Get PDF
    Models play a vital role in supporting a range of activities in numerous domains. We rely on models to support the design, visualisation, analysis and representation of parts of the world around us, and as such significant research effort has been invested into numerous areas of modelling; including support for model semantics, dynamic states and behaviour, temporal data storage and visualisation. Whilst these efforts have increased our capabilities and allowed us to create increasingly powerful software-based models, the process of developing models, supporting tools and /or data structures remains difficult, expensive and error-prone. In this paper we define from literature the key factors in assessing a model’s quality and usefulness: semantic richness, support for dynamic states and object behaviour, temporal data storage and visualisation. We also identify a number of shortcomings in both existing modelling standards and model development processes and propose a unified generic process to guide users through the development of semantically rich, dynamic and temporal models

    MusA: Using Indoor Positioning and Navigation to Enhance Cultural Experiences in a museum

    Get PDF
    In recent years there has been a growing interest into the use of multimedia mobile guides in museum environments. Mobile devices have the capabilities to detect the user context and to provide pieces of information suitable to help visitors discovering and following the logical and emotional connections that develop during the visit. In this scenario, location based services (LBS) currently represent an asset, and the choice of the technology to determine users' position, combined with the definition of methods that can effectively convey information, become key issues in the design process. In this work, we present MusA (Museum Assistant), a general framework for the development of multimedia interactive guides for mobile devices. Its main feature is a vision-based indoor positioning system that allows the provision of several LBS, from way-finding to the contextualized communication of cultural contents, aimed at providing a meaningful exploration of exhibits according to visitors' personal interest and curiosity. Starting from the thorough description of the system architecture, the article presents the implementation of two mobile guides, developed to respectively address adults and children, and discusses the evaluation of the user experience and the visitors' appreciation of these application

    Time indeterminacy and spatio-temporal building transformations: an approach for architectural heritage understanding

    Get PDF
    Nowadays most digital reconstructions in architecture and archeology describe buildings heritage as awhole of static and unchangeable entities. However, historical sites can have a rich and complex history, sometimes full of evolutions, sometimes only partially known by means of documentary sources. Various aspects condition the analysis and the interpretation of cultural heritage. First of all, buildings are not inexorably constant in time: creation, destruction, union, division, annexation, partial demolition and change of function are the transformations that buildings can undergo over time. Moreover, other factors sometimes contradictory can condition the knowledge about an historical site, such as historical sources and uncertainty. On one hand, historical documentation concerning past states can be heterogeneous, dubious, incomplete and even contradictory. On the other hand, uncertainty is prevalent in cultural heritage in various forms: sometimes it is impossible to define the dating period, sometimes the building original shape or yet its spatial position. This paper proposes amodeling approach of the geometrical representation of buildings, taking into account the kind of transformations and the notion of temporal indetermination
    • 

    corecore