University of Cyprus

About: University of Cyprus is a education organization based out in Nicosia, Cyprus. It is known for research contribution in the topics: Large Hadron Collider & Context (language use). The organization has 3624 authors who have published 15157 publications receiving 412135 citations.

GridStat: A Flexible QoS-Managed Data Dissemination Framework for the Power Grid

Abstract: With the increase in the monitoring of operational data at very high rates in high voltage substations and the ability to time synchronize these data with global positioning systems, there is a growing need for transmitting this data for monitoring, operation, protection, and control needs. The sets of data that need to be transferred and the speed at which they need to be transferred depend on the application-for example, slow for postevent analysis, near real time for monitoring and as close to real time as possible for control or protection. In this paper, we describe GridStat, a novel middleware framework we have developed to provide flexible, robust, and secure data communications for the power grid's operations. Test results demonstrate that such a flexible framework can also guarantee latency that is suitable for fast wide-area protection and control.

Full-Duplex Cooperative Cognitive Radio with Transmit Imperfections

Abstract: This paper studies the cooperation between a primary system and a cognitive system in a cellular network where the cognitive base station (CBS) relays the primary signal using amplify-and-forward or decode-and-forward protocols, and in return it can transmit its own cognitive signal. While the commonly used half-duplex (HD) assumption may render the cooperation less efficient due to the two orthogonal channel phases employed, we propose that the CBS can work in a full-duplex (FD) mode to improve the system rate region. The problem of interest is to find the achievable primary-cognitive rate region by studying the cognitive rate maximization problem. For both modes, we explicitly consider the CBS transmit imperfections, which lead to the residual self-interference associated with the FD operation mode. We propose closed-form solutions or efficient algorithms to solve the problem when the related residual interference power is non-scalable or scalable with the transmit power. Furthermore, we propose a simple hybrid scheme to select the HD or FD mode based on zero-forcing criterion, and provide insights on the impact of system parameters. Numerical results illustrate significant performance improvement by using the FD mode and the hybrid scheme.

Study of double parton scattering using W + 2-jet events in proton-proton collisions at √s = 7 TeV

Abstract: Double parton scattering is investigated in proton-proton collisions at sqrt(s) = 7 TeV where the final state includes a W boson, which decays into a muon and a neutrino, and two jets. The data sample corresponds to an integrated luminosity of 5 inverse femtobarns, collected with the CMS detector at the LHC. Observables sensitive to double parton scattering are investigated after being corrected for detector effects and selection efficiencies. The fraction of W + 2-jet events due to double parton scattering is measured to be 0.055 +/- 0.002 (stat.) +/- 0.014 (syst.). The effective cross section, sigma[eff], characterizing the effective transverse area of hard partonic interactions in collisions between protons is measured to be 20.7 +/- 0.8 (stat.) +/- 6.6 (syst.) mb.