Search results for "VDP::Technology: 500::Information and communication technology: 550::Telecommunication: 552"
showing 10 items of 87 documents
Two Teletraffic-based Schemes for Energy Saving in Cellular Networks with Micro-cells
2012
Published version of an article in the journal: Journal of Communications. Also available from the publisher at: http://dx.doi.org/10.4304/jcm.7.10.726-739 Open access The energy consumption of Base Stations (BSs) is known to constitute a major part of the power consumption in a cellular network. In this paper, we propose a novel approach which may switch a BS off under light traffic conditions in order to conserve the power consumption of such networks. More specifically, when the traffic load in the middle cell of a network with three micro-cells is sufficiently low, the corresponding BS can be switched off and its users will be covered by increasing the transmission power of one sector a…
Improving the Performance Metric of Wireless Sensor Networks with Clustering Markov Chain Model and Multilevel Fusion
2013
Published version of an article in the journal: Mathematical Problems in Engineering. Also available from the publisher at: http://dx.doi.org/10.1155/2013/783543 Open access The paper proposes a performance metric evaluation for a distributed detection wireless sensor network with respect to IEEE 802.15.4 standard. A distributed detection scheme is considered with presence of the fusion node and organized sensors into the clustering and non-clustering networks. Sensors are distributed in clusters uniformly and nonuniformly and network has multilevel fusion centers. Fusion centers act as heads of clusters for decision making based on majority-like received signal strength (RSS) with comparis…
LCRT: A ToA Based Mobile Terminal Localization Algorithm in NLOS Environment
2009
©2009 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE. Article also available from publisher: http://dx.doi.org/10.1109/VETECS.2009.5073644 Non line-of-sight (NLOS) propagation in range measurement is a key problem for mobile terminal localization. This paper proposes a low computational residual test (LCRT) algorithm that can identify the number of line-of-sight (LOS) transmissions and reduce the computational com…
Performance Analysis of Cooperative Communication Systems with Imperfect Channel Estimation
2009
This paper investigates the effects of channel estimation errors on the symbol-error-rate (SER) performance of a cooperative communication system operating in an amplify-and- forward (AF) mode. A pilot symbol assisted modulation scheme with linear minimum mean square estimation (LMMSE) is used for the channel estimation. An accurate and easy-to-evaluate SER expression is presented for uncoded cooperative communication systems with quadrature amplitude modulation (QAM) and phase-shift keying (PSK) constellations. Numerical simulations are conducted to verify the correctness of the proposed analytical formulation. It is shown that the performance loss caused by channel estimation errors incre…
Delivering Services to Residential Appliances by Utilizing Remote Resource Awareness
2008
Service providers are nowadays offering a variety of services, and in particular multimedia content delivery. Besides, consumer appliances are increasingly becoming digitalized including support for communication networks. However, it is difficult, and in many cases impossible, to use these services with standard consumer appliances, such as TV and media player devices. Rather, usage is often restricted so that they can only be accessed through web browsers from PCs, mobile phones and similar terminals. This is unfortunate, because dedicated consumer appliances are often better suited to handle the content and thereby give consumers a better experience. Within this paper, three design appro…
Broadband Internet Access via Multi-Hop Wireless Mesh Networks: Design, Protocol and Experiments
2010
Published version of an article from the journal: Wireless Personal Communications. The original publication is available at Spingerlink. http://dx.doi.org/10.1007/s11277-009-9907-9 While bandwidth for Internet access in urban areas is steadily increasing in recent years, many rural areas are still suffering from the effect of the digital divide. This paper presents a broadband Internet access paradigm developed in the context of the ADHOCSYS project, which was financed by the European Commission under the 6th Framework Program Information and Society Technologies, within the strategic objective of Broadband for All. Aiming at providing reliable Internet access in rural and mountainous regi…
Secure and efficient data storage in unattended wireless sensor networks
2009
©2009 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE. Article also available from publisher: http://dx.doi.org/10.1109/NTMS.2009.5384753 Providing forward and backward secrecy is still a big challenge in Unattended Wireless Sensor Networks (UWSNs), though some storage schemes have been proposed. Additionally, high storage requirement needs efficient storage techniques. In this paper, we propose a novel homomorphic…
Media Delivery to Remote Renderers Controlled by the Mobile Phone
2009
In today's content delivery solutions, service delivery and control are still tightly coupled, a service typically being delivered to the same device that controls the session. We present a solution that was designed with the goal to decouple service control and delivery. Using our approach, multimedia streaming services can be delivered to off-the-shelf DLNA devices in visited networks. The service provider receives information about the remote media player and access environment via a mobile phone. Proximity technologies (e.g. barcodes, NFC) of the control device are used for the exchange of required credentials. This paper describes a typical scenario and our prototype implementation.
Discovering web services in social web service repositories using deep variational autoencoders
2020
Abstract Web Service registries have progressively evolved to social networks-like software repositories. Users cooperate to produce an ever-growing, rich source of Web APIs upon which new value-added Web applications can be built. Such users often interact in order to follow, comment on, consume and compose services published by other users. In this context, Web Service discovery is a core functionality of modern registries as needed Web Services must be discovered before being consumed or composed. Many efforts to provide effective keyword-based service discovery mechanisms are based on Information Retrieval techniques as services are described using structured or unstructured textdocumen…
Mobile Security with Location-Aware Role-Based Access Control
2012
Published version of an article from the book: Security and privacy in mobile information and communication systems. Also available on SpringerLink: http://dx.doi.org/10.1007/978-3-642-30244-2_15 This paper describes how location-aware Role-Based Access Control (RBAC) can be implemented on top of the Geographically eXtensible Access Control Markup Language (GeoXACML). It furthermore sketches how spatial separation of duty constraints (both static and dynamic) can be implemented using GeoXACML on top of the XACML RBAC profile. The solution uses physical addressing of geographical locations which facilitates easy deployment of authorisation profiles to the mobile device. Location-aware RBAC c…