Search results for "VDP::Technology: 500"
showing 10 items of 538 documents
Greedy versus Dynamic Channel Aggregation Strategy in CRNs: Markov Models and Performance Evaluation
2011
Publishes version of a paper from the book: Networking 2011 Workshops. Also available f rom the publisher on SpringLink:http://dx.doi.org/10.1007/978-3-642-23041-7_3 In cognitive radio networks, channel aggregation techniques which aggregate several channels together as one channel have been proposed in many MAC protocols. In this paper, we consider elastic data traffic and spectrum adaptation for channel aggregation, and propose two new strategies named as Greedy and Dynamic respectively. The performance of channel aggregation represented by these strategies is evaluated using continuous time Markov chain models. Moreover, simulation results based on various traffic distributions are utili…
Medium access in cognitive radio networks: From single hop to multiple hops
2012
Doktorgradsavhandling i informasjons- og kommunikasjonsteknologi, Universitetet i Agder, Grimstad, 2012 If channel assembling is enabled, this technique can be utilized for potential performance improvement in CRNs. Two use cases are envisaged for channel assembling. In the first use case, the system can accommodate parallel SU services in multiple channels, while in the second use case, the system allows only one SU service at a time. In the use case where parallel SU services are allowed, various channel assembling strategies are proposed and modeled in order to investigate their performance and to acquire better comprehension of the behavior of CRNs with channel assembling. Moreover, the…
“Sven and the Media Portal” : A Nomadic Use Case for the Extended Home
2006
The Networked and Electronic Media Technology Platform (NEM) [5] states that users will consume an “innovative mix of various media forms, delivered seamlessly over technologically transparent networks, to improve the quality, enjoyment and value of life. [6] visualizes a future use case and some of the challenges that need to be addressed before the NEM vision becomes reality.
A continuous-space analytical approach for relay node placement in hybrid cellular and ad hoc 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/ISWCS.2009.5285305 A hybrid network is composed of a cellular component and an ad hoc component connected by a relay node, for the purpose of coverage extension and/or capacity improvement. In this paper, we analyze the capacity of such a hybrid network by employing a continuous-space analytical …
Remote service usage through SIP with multimedia access as a use case
2007
The IP Multimedia Subsystem is under deployment, as an IP-based service control and access infrastructure, but how it interconnects with residential appliances is currently unclear. With IMS access for the residential appliances they can be used as both service consumers and service providers. In this paper we present a protocol which allows residential services to be remotely invoked, through the IMS, and consumed in a different network, along with a prototype implementation and early results. With our protocol services of two distinct service protocol systems can cooperate.
Channel simulation models for mobile broadband communication systems
2009
Doktorgradsavhandling i informasjons- og kommunikasjonsteknologi, Universitetet i Agder, Grimstad, 2009 Mobile broadband wireless communication systems (MBWCS) are emerging as a solution to provide broadband services to users on the move. These systems are expected to operate in a wide variety of propagation scenarios, at different mobile speeds, and at various frequency bands. Under such a variety of requirements, flexible and efficient channel simulation models will prove fundamental for the laboratory analysis of MBWCS. Currently, most of the existing channel simulation models are either too complex as to allow for an efficient performance investigation of MBWCS, or they cannot be applie…
Using Digital Hydraulics in Secondary Control of Motor Drive
2020
Due to the increased focus on pollution and global warming, there is a demand for energy efficient systems. This also applies to the offshore oil and gas industry. Normally used hydraulic systems tend to suffer from low energy efficiency, especially when operating with part loads. In the last decades, a new pump and motor technology has experienced increased interest due to the potential of high energy efficiency in a wide range of operation conditions. This new technology is called digital displacement machine technology. Nowadays, there is a desire from the offshore oil and gas industry to use this digital displacement machine technology to design highly efficient hydraulic winch drive sy…
Stability analysis with H∞ performance of production networks with autonomous work systems and time-varying delays
2011
Author's version of a chapter in the book: Proceeding of the 30th Chinese Control Conference. Also available from the publisher at: http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=6001452&tag=1 This paper considers the problem of stability analysis with an H ∞ performance for a class of production networks of autonomous work systems with delays in the capacity changes. The system under consideration shares information between work systems and the work systems adjust capacity with the objective of maintaining a desired amount of local work in progress. An appropriate Lyapunov function is utilized to establish some delay-range-dependent conditions in terms of linear matrix inequalitie…
Local Capacity Control for Production Networks of Autonomous Work Systems With Time-Varying Delays
2010
Published version of an article in the journal: IEEE Transactions on Automation Science and Engineering. Also available from publisher: http://dx.doi.org/10.1109/TASE.2010.2046735. (c) 2010 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works This paper considers the problem of local capacity H infinity control for a class of production networks of autonomous work systems with time-varying delays in the…
A parameter-dependent approach to observer-based H ∞ control for networked control LPV systems
2014
Published version of an article in the journal: Mathematical Problems in Engineering. Also available from the publisher at: http://dx.doi.org/10.1155/2014/698075 We address the observer-based H ∞ controller design problem for networked control LPV (NC LPV) systems, which are network-based systems that depend on unknown but measurable time-varying parameters. According to the analysis of the special issues brought by introducing network into LPV systems and the state reconstruction based on the observer, a new augmented model is established with two independent time-varying delays, which can carry out the controller and observer collaborative design effectively. Based on the parameter-depend…