Search

A cross-layer optimization method is presented for video transmission over multirate generalized multicarrier code division multiple access (GMC-CDMA) wireless links. Findings reveal the optimization of the proposed method in the operational rate-distortion sense.

This paper examines the role of renewable energy sources (RES), especially the sun, as a potential solution for solar radiation management concerns. It states how photovoltaic (PV), especially low-cost PV and other thin film technology, can be applied and what impact and share they can have on the European market – using the Cyprus market as an example of strategic implementation. The Energy Service of the Ministry of Energy, Commerce, Industry and Tourism currently reports a 7.5% share (as at end of 2012) of RES in overall final energy consumption and suggests ways in which that share can increase. In the near future, PVs will be the most significant electricity source if the cost per kWh produced is further reduced, as was proven recently during the award procedures for PV systems. [ABSTRACT FROM AUTHOR]

In this paper, we consider the problem of video transmission over wireless generalized multicarrier code division multiple access (GMC-CDMA) systems. Such systems offer deterministic elimination of multiple access interference. A scalable video source codec is used and a multirate setup is assumed, i.e., each video user is allowed to occupy more than one GMC-CDMA channels. Furthermore, each of these channels can utilize a different number of subcarriers. We propose a cross-layer optimization method to select the source coding rate, channel coding rate, number of subcarriers per GMC-CDMA channel and transmission power per GMC-CDMA channel given a maximum transmission power for each video user and an available chip rate. Universal rate distortion characteristics (URDC) are used to approximate the expected distortion at the receiver. The proposed algorithm is optimal in the operational rate distortion sense, subject to the specific setup used and the approximation caused by the use of the URDC. Experimental results are presented and conclusions are drawn. [ABSTRACT FROM AUTHOR]

Abstract: A Project funded by the Research Promotion Foundation of Cyprus was undertaken by the Cyprus University of Technology and other collaborators, to investigate and determine the geothermal parameters of the ground in Cyprus since such information is currently unavailable. The purpose of this paper is to report on the ground temperatures collected by now, at the six representative sites in relation to depth, time of the year, structure of the ground and altitude and report on their impact on the efficiency of Ground Coupled Heat Pumps. Every month since October 2009, the temperature of the ground is being recorded along the depth of the boreholes. It is anticipated that the project will be completed by the end of 2010 and geothermal information will be collected and reported for all six locations. The data collected until now clearly indicate that there is a potential for the efficient use of GCHPs in Cyprus leading to significant savings in power. [Copyright &y& Elsevier]