Search results for "Protocol"
showing 10 items of 1808 documents
Delfos: the Oracle to Predict NextWeb User's Accesses
2007
Despite the wide and intensive research efforts focused on Web prediction and prefetching techniques aimed to reduce user's perceived latency, few attempts to implement and use them in real environments have been done, mainly due to their complexity and supposed limitations that low user available bandwidths imposed few years ago. Nevertheless, current user bandwidths open a new scenario for prefetching that becomes again an interesting option to improve web performance. This paper presents Delfos, a framework to perform web predictions and prefetching on a real environment that tries to cover the existing gap between research and praxis. Delfos is integrated in the web architecture without…
Semantic web technologies for facilities management
2007
Facility management is the practice of coordinating the physical workplace with the people and work of the organization. It integrates the principles of business administration, architecture and the behavioral and engineering sciences. To deal with these requirements, we have developed a framework based on Semantic Web technologies: RDF, OWL, SWRL and named graph. This framework, called C-DMF, allows facilities manager to organize all knowledge generating during building lifecycle in end-user contextual graphs.
Context DataModel Framework: semantic facilities management
2008
Facility management is the practice of coordinating the physical workplace with the people and work of the organisation. It integrates the principles of business administration, architecture and the behavioural and engineering sciences. Software dedicated to facility management are usually limited to spreadsheet software. With the development of the Industry Foundation Class (IFC; a new object-oriented standard to model buildings) and web-based networks, a new generation of methods and tools dedicated to facility management are required. To deal with these requirements, we have developed a framework based on Semantic Web technologies: RDF, Ontology Web Language (OWL), Semantic Web Rule Lang…
Ontology languages for the semantic web: A never completely updated review
2006
This paper gives a never completely account of approaches that have been used for the research community for representing knowledge. After underlining the importance of a layered approach and the use of standards, it starts with early efforts used for artificial intelligence researchers. Then recent approaches, aimed mainly at the semantic web, are described. Coding examples from the literature are presented in both sections. Finally, the semantic web ontology creation process, as we envision it, is introduced.
OGC-to-W3C Services: A Wrapper-Based Solution for Geospatial Metadata Exchange
2018
When trying to compose services that are developed according to different standards, interoperability issues arise that are often faced by developing ad-hoc solutions. A typical example is represented by the composition of W3C and OGC services, which were developed more or less concurrently by independent organizations. In such a context, developing a wrapper that abstracts as much as possible the inner details and logic of a wrapped service well embraces the low-coupled nature of the general Service Oriented Computing paradigm. This paper focuses on the proper management of geospatial metadata into a W3C-based environment and is based on the development of a wrapper that exposes OGC functi…
Ontology-based Semantic Web Service platform in Mobile Environments
2006
The number of mobile terminals is continuously increasing in the world, although in many developed countries the market has saturated. Thus, the market can only grow if new service types are offered to the mobile terminals. One emerging technology that might make this possible is semantic web services. At the core of this technology are ontologies that are necessary for automatic discovery and composition of the services. In this paper we discuss how mobility affects the architectural considerations of semantic web service platform and particularly ontology management. We rely on reference architecture for Semantic Web Services in our work.
WiSHFUL : enabling coordination solutions for managing heterogeneous wireless networks
2017
The paradigm shift toward the Internet of Things results in an increasing number of wireless applications being deployed. Since many of these applications contend for the same physical medium (i.e., the unlicensed ISM bands), there is a clear need for beyond-state-of-the-art solutions that coordinate medium access across heterogeneous wireless networks. Such solutions demand fine-grained control of each device and technology, which currently requires a substantial amount of effort given that the control APIs are different on each hardware platform, technology, and operating system. In this article an open architecture is proposed that overcomes this hurdle by providing unified programming i…
Energy-aware design for wireless mesh networks
2014
International audience; Wireless mesh networks (WMNs) are the next step in the development of the wireless architecture, delivering wireless services for a large variety of users in personal, local, campus, and metropolitan areas. Energy efficiency solutions are becoming more vital for both local access networks and wireless networks and Green IT has attracted a considerable attention. However, the application of green network for wireless mesh networks has seldom been described in the literature. However, WMNs infrastructure devices are always active. Thus, during lower traffic periods the energy consumption is the same as in busy hours, while it would be possible to save a large amount of…
WINSE: WiMAX NS-2 extension
2009
IEEE 802.16 standard defines the wireless broadband technology called WiMAX. When compared to other wireless technologies, it introduces many interesting advantages at PHY, MAC, and QoS layers. Heavy simulations are needed to study IEEE 802.16 performance and propose further enhancements to this standard. Link level simulations are not always sufficient, while system level simulators are not always accurate to capture MAC and transport protocol details. We implemented a 802.16 extension for the NS-2 network simulator. It includes upper PHY modeling, almost all the features of the 802.16 MAC layer, as well as the QoS framework. This article describes the implemented features, simulation meth…
Supporting a Pseudo-TDMA Access Scheme in Mesh Wireless Networks
2013
Wireless mesh networks appear a promising solution for pro- viding ubiquitous low-cost wireless access, but cannot rely on simple CSMA access protocols because of the critical inefficiencies that arise in topologies with hidden nodes. To overcome these limitations, some important protocol extensions based on synchronization and reservation mechanisms have been ratified. In this paper we show that an alternative approach to the standardiza- tion of new features and signaling messages for mesh networks can be the utilization of programmable nodes able to execute different MAC protocols programmed on the fly. Signaling messages are used only for disseminating the new protocol among the nodes. …