3,169 research outputs found

    Virtual Location-Based Services: Merging the Physical and Virtual World

    Get PDF
    Location-based services gained much popularity through providing users with helpful information with respect to their current location. The search and recommendation of nearby locations or places, and the navigation to a specific location are some of the most prominent location-based services. As a recent trend, virtual location-based services consider webpages or sites associated with a location as 'virtual locations' that online users can visit in spite of not being physically present at the location. The presence of links between virtual locations and the corresponding physical locations (e.g., geo-location information of a restaurant linked to its website), allows for novel types of services and applications which constitute virtual location-based services (VLBS). The quality and potential benefits of such services largely depends on the existence of websites referring to physical locations. In this paper, we investigate the usefulness of linking virtual and physical locations. For this, we analyze the presence and distribution of virtual locations, i.e., websites referring to places, for two Irish cities. Using simulated tracks based on a user movement model, we investigate how mobile users move through the Web as virtual space. Our results show that virtual locations are omnipresent in urban areas, and that the situation that a user is close to even several such locations at any time is rather the normal case instead of the exception

    Knowledge Discovery in the SCADA Databases Used for the Municipal Power Supply System

    Full text link
    This scientific paper delves into the problems related to the develop-ment of intellectual data analysis system that could support decision making to manage municipal power supply services. The management problems of mu-nicipal power supply system have been specified taking into consideration modern tendencies shown by new technologies that allow for an increase in the energy efficiency. The analysis findings of the system problems related to the integrated computer-aided control of the power supply for the city have been given. The consideration was given to the hierarchy-level management decom-position model. The objective task targeted at an increase in the energy effi-ciency to minimize expenditures and energy losses during the generation and transportation of energy carriers to the Consumer, the optimization of power consumption at the prescribed level of the reliability of pipelines and networks and the satisfaction of Consumers has been defined. To optimize the support of the decision making a new approach to the monitoring of engineering systems and technological processes related to the energy consumption and transporta-tion using the technologies of geospatial analysis and Knowledge Discovery in databases (KDD) has been proposed. The data acquisition for analytical prob-lems is realized in the wireless heterogeneous medium, which includes soft-touch VPN segments of ZigBee technology realizing the 6LoWPAN standard over the IEEE 802.15.4 standard and also the segments of the networks of cellu-lar communications. JBoss Application Server is used as a server-based plat-form for the operation of the tools used for the retrieval of data collected from sensor nodes, PLC and energy consumption record devices. The KDD tools are developed using Java Enterprise Edition platform and Spring and ORM Hiber-nate technologies

    Orientation twisted homotopy field theories and twisted unoriented Dijkgraaf-Witten theory

    No full text
    Given a finite Z2\mathbb{Z}_2-graded group G^\hat{\mathsf{G}} with ungraded subgroup G\mathsf{G} and a twisted cocycle λ^∈Zn(BG^;U(1)π)\hat{\lambda} \in Z^n(B \hat{\mathsf{G}}; \mathsf{U}(1)_{\pi}) which restricts to λ∈Zn(BG;U(1))\lambda \in Z^n(B \mathsf{G}; \mathsf{U}(1)), we construct a lift of λ\lambda-twisted G\mathsf{G}-Dijkgraaf--Witten theory to an unoriented topological quantum field theory. Our construction uses a new class of homotopy field theories, which we call orientation twisted. We also introduce an orientation twisted variant of the orbifold procedure, which produces an unoriented topological field theory from an orientation twisted G\mathsf{G}-equivariant topological field theory

    Lightning Imaging Sensor (LIS) for the Earth Observing System

    Get PDF
    Not only are scientific objectives and instrument characteristics given of a calibrated optical LIS for the EOS but also for the Tropical Rainfall Measuring Mission (TRMM) which was designed to acquire and study the distribution and variability of total lightning on a global basis. The LIS can be traced to a lightning mapper sensor planned for flight on the GOES meteorological satellites. The LIS consists of a staring imager optimized to detect and locate lightning. The LIS will detect and locate lightning with storm scale resolution (i.e., 5 to 10 km) over a large region of the Earth's surface along the orbital track of the satellite, mark the time of occurrence of the lightning, and measure the radiant energy. The LIS will have a nearly uniform 90 pct. detection efficiency within the area viewed by the sensor, and will detect intracloud and cloud-to-ground discharges during day and night conditions. Also, the LIS will monitor individual storms and storm systems long enough to obtain a measure of the lightning flashing rate when they are within the field of view of the LIS. The LIS attributes include low cost, low weight and power, low data rate, and important science. The LIS will study the hydrological cycle, general circulation and sea surface temperature variations, along with examinations of the electrical coupling of thunderstorms with the ionosphere and magnetosphere, and observations and modeling of the global electric circuit

    NASA space research and technology overview (ITP)

    Get PDF
    A series of viewgraphs summarizing NASA space research and technology is presented. Some of the specific topics covered include the organization and goals of the Office of Aeronautics and Space Technology, technology maturation strategy, integrated technology plan for the Civil Space Program, program selection and investment prioritization, and space technology benefits

    Mobile-cloud Cross Development (McX)

    Get PDF
    There is a multitude of Mobile Operating Systems (MOSs) with iOS, Android, Windows Phone and, BlackBerry leading the space. New players continue to enter the market. Without a de-facto leader in this space, it has become necessary for businesses & developers to target multiple devices & MOSs in order to establish a relevant presence within their target audience. Cross-platform Mobile Development Tools (XMTs) were born out of this need to reduce developer effort in creating mobile applications by providing “write once run anywhere” (WORA) functionality. However, most of these tools sacrifice performance, features or maintainability in order to provide WORA functionality. Furthermore, these tools only attempt to manage the user interface and related client-side functionality. Most mobile applications need to follow the same principals that guide development of non-mobile web or desktop apps. Typical apps are deployed using an n-tier, cloud-based strategy with substantial functionality delegated to cloud resources. Given the above, there are two parts of an application’s anatomy that don’t get much attention – the cloud middleware functionality, and the database/model management features. In this paper I address these problems through creation of a Mobile-cloud Cross Development (McX) tool-chain that includes a type-safe meta-programming language, an integrated cloud node and, an active compiler. In order to effectively understand the problem with the current state of the art, I use 3 of the leading XMTs alongside the developed McX tool-chain and compare the effectiveness of each. The paper further introduces the language; it’s grammar and semantic structure, and provides discussions on how this approach fits the future of cross-platform, cloud-integrated mobile application development along with the associated issues and areas for further research

    Performance assessment of RDF graph databases for smart city services

    Get PDF
    Abstract Smart cities are providing advanced services aggregating and exploiting data from different sources. Cities collect static data such as road graphs, service description, as well as dynamic/real time data like weather forecast, traffic sensors, bus positions, city sensors, events, emergency data, flows, etc. RDF stores may be used to set up knowledge bases integrating heterogeneous information for web and mobile applications to use the data for new advanced services to citizens and city administrators, thus exploiting inferential capabilities, temporal and spatial reasoning, and text indexing. In this paper, the needs and constraints for RDF stores to be used for smart cities services, together with the currently available RDF stores are evaluated. The assessment model allows a full understanding of whether an RDF store is suitable to be used as a basis for Smart City modeling and applications. The RDF assessment model is also supported by a benchmark which extends available RDF store benchmarks at the state the art. The comparison of the RDF stores has been applied on a number of well-known RDF stores as Virtuoso, GraphDB (former OWLIM), Oracle, StarDog, and many others. The paper also reports the adoption of the proposed Smart City RDF Benchmark on the basis of Florence Smart City model, data sets and tools accessible as Km4City Http://www.Km4City.org , and adopted in the European Commission international smart city projects named RESOLUTE H2020, REPLICATE H2020, and in Sii-Mobility National Smart City project in Italy
    • 

    corecore