Search results for "communications"

A Guaranteed performance of a green data center based on the contribution of vital nodes

2016

International audience; In order to satisfy the need for the critical computing resources, many data center architectures proposed to house a huge number of network devices. These devices are used to achieve the highest performance in case of full utilization of the network. However, the peak capacity of the network is rarely reached. Consequently, many devices are set into idle state and cause a huge energy waste leading to a non-proportionality between the network load and the energy consumed. In this paper, we propose a power-aware routing algorithm that saves energy consumption with a negligible trade-off on the performance of the network. The idea is to keep active only the source and …

Achieving energy efficiency in data centers with a performance-guaranteed power aware routing

2017

Nowadays, data centers are designed to offer the highest performance in case of high traffic load and peak utilisation of the network. However, in a realistic data center environment, the peak capacity of the network is rarely reached and the average utilisation of devices varies between 5% and 25% which results into a huge loss of energy since most of the time links and servers are idle or under-utilized. The high impact of this wasted power on environmental effects, energy needs and electricity costs raised the concerns to seek for an efficient solution to make data centers more power effective while keeping the desired quality of service. In this paper, we propose a power-aware routing a…

Special issue on the occasion of the International Workshop on Complex Networks and their Applications

2014

On the path representation of networks

1982

A compact data structure for networks is obtained by storing arcs of paths sequentially. This structure allows forward and backward access from a node to its neighbors.

Network structure and optimal technological innovation

2019

The role of networks in the emergence, diffusion and evolution of technological innovations has attracted much theoretical and empirical attention. Yet, much of the work has explored the role of undirected and homogeneous networks. In real cases, many networks are directed. The flow of information, benefits or observations is directed from one node towards another node. Real networks are also heterogeneous, for example, few nodes have a high degree while many others have a low degree. In this article, we report on the results of an evolutionary agent-based model in which a group of agents, in our case firms, collectively search a complex (rugged) technological landscape and observe each oth…

The Development of Students’ Metacognitive Competences. A Case Study

2010

In the information society metacognitive competencies are essential. Based on some activities from the Enrichment Instrumental Program elaborated by professor Reuven Feuerstein we have designed a program for developing the students capacities of selfcontrol, selfknowing and intelectual learning strategies. The case study presents the formation of students’ metacognitive competences at the "Lucian Blaga" University of Sibiu, "Hermann Oberth" Faculty of Enginereeing, Department of Computers Sciences. A Web based application has been developed in order to enable students to self-evaluate their metacognitive competencies and to acquire self-regulatory abilities.

New super-orthogonal space-time trellis codes using differential M-PSK for noncoherent mobile communication systems with two transmit antennas

2010

Published version of an article in the journal: Annals of Telecommunications-Annales Des Telecommunications. Also available from the publisher at: http://dx.doi.org/10.1007/s12243-010-0191-1 In this paper, we develop super-orthogonal space-time trellis codes (SOSTTCs) using differential binary phase-shift keying, quadriphase-shift keying and eight-phase shift keying for noncoherent communication systems with two transmit antennas without channel state information at the receiver. Based on a differential encoding scheme proposed by Tarokh and Jafarkhani, we propose a new decoding algorithm with reduced decoding complexity. To evaluate the performance of the SOSTTCs by way of computer simulat…

An Improved Detection Technique for Cyclic-Prefixed OFDM

2010

A novel Orthogonal Frequency Division Multiplexing detection technique compatible to standard (e.g. Wireless LAN) transmitters is proposed. It features enhanced error-rate performance with flexible computational complexity and robustness to imperfect channel estimation. It is based on exploitation of the redundancy available in the cyclic prefix after cancellation of interference from the preceding block. In order to show the effectiveness of our proposal, an analysis of computational complexity and a number of comparisons to the standard per-subcarrier receiver and a previously existing method in terms of error rates are reported.

Population Monte Carlo Schemes with Reduced Path Degeneracy

2017

Population Monte Carlo (PMC) algorithms are versatile adaptive tools for approximating moments of complicated distributions. A common problem of PMC algorithms is the so-called path degeneracy; the diversity in the adaptation is endangered due to the resampling step. In this paper we focus on novel population Monte Carlo schemes that present enhanced diversity, compared to the standard approach, while keeping the same implementation structure (sample generation, weighting and resampling). The new schemes combine different weighting and resampling strategies to reduce the path degeneracy and achieve a higher performance at the cost of additional low computational complexity cost. Computer si…

Too Much or Too Little Messaging? Situational Determinants of Guilt About Mobile Messaging

2021

Abstract Mobile messaging has been associated with guilt. Guilt about too much messaging may result from self-control failures during goal conflicts. Conversely, guilt about too little messaging may result from violating the salient norm to be available. This research considers both boundary conditions of guilt about mobile communication—goal conflicts and availability norm salience—simultaneously for the first time. We conducted two preregistered experiments to investigate their interplay. Results from a vignette experiment, but not from a laboratory experiment, support the hypotheses that goal conflicts trigger guilt about using messengers and that guilt about not using messengers arises …