Search results for "2008"
showing 10 items of 71 documents
Analysis of the limitations of WiFi communications managed by the IEEE 802.11 protocol in data transmission in automated power distribution systems
2010
This paper presents a study on the performances of the IEEE 802.11 protocol used in a Medium Voltage networks management system, carried out using a model for the simulation of WiFi chains architectures. The results of the simulations give some practical indications for the use of the IEEE 802.11 protocol also in presence of transmissions characterized by rigid time intervals, for which this protocol is usually not suitable. Finally the whole communications system is presented.
Assessing the effectiveness of IEEE 802.11e in multi-hop mobile network environments
2004
The IEEE 802.11e technology is receiving much interest due to the promising enhancements it offers to wireless local area networks in terms of QoS support. Until now, research has focused on single hop, access point based environments, which are the most common. We review the enhancements proposed in the last IEEE 802.11e draft (version 8.0). We analyze the performance of the IEEE 802.11e protocol on ad-hoc networks (multi-hop) in terms of throughput and end-to-end delay. We also measure the effectiveness for static and fully dynamic networks with a variable number of source stations. Finally, we analyze the performance of IEEE 802.11e when legacy IEEE 802.11 stations (no IEEE 802.11e suppo…
QoS Support for Time-Constrained Multimedia Communications in IEEE 802.11 WLANs: A Performance Evaluation
2005
During the past few years, we have been witnessing the massive deployment of IEEE 802.11 wireless LANs. Even though the widespread deployment of such wireless LANs, many studies are still underway aiming to design and develop simple yet effective QoS mechanisms for supporting time-constrained services over such platforms. In this paper, we first overview five different QoS mechanisms recently introduced in the literature as well as the upcoming IEEE 802.11e (EDCA) standard. We then carry out a comparative performance evaluation of all the QoS mechanisms. We focus our study on the effectiveness of the various QoS mechanisms for supporting time-constrained services.
Liberalizing Industrial Relations in Southern-Europe: Towards the End of a Coordinated and Egalitarian Model
2016
The paper focuses on the changes that occurred to the architecture of industrial relations in Southern-European countries during the last decade. In particular, the bargaining systems of Italy, France, Spain, Greece and Portugal are compared, with a particular attention to the legislative measures enacted under the influence of international institutions after the 2008 financial and sovereign debt crisis. The theoretical framework, under which the process of transformation is analysed, is the literature on comparative politics as recently reviewed by Thelen. At the same time, the work takes into account the labour law dogmatic category of "inderogability", represented by the couple law-bran…
Radiocarbon dates, accumulation rates, δ¹³C and July temperature of profiles obtained from Selwyn and Misaw Lake, subarctic Canada
2010
The rapid warming of arctic regions during recent decades has been recorded by instrumental monitoring, but the natural climate variability in the past is still sparsely reconstructed across many areas. We have reconstructed past climate changes in subarctic west-central Canada. Stable carbon and oxygen isotope ratios (d13C, d18O) were derived from a single Sphagnum fuscum plant component; alpha-cellulose isolated from stems. Periods of warmer and cooler conditions identified in this region, described in terms of a "Mediaeval Climatic Anomaly" and "Little Ice Age" were registered in the temperature reconstruction based on the d13C record. Some conclusions could be drawn about wet/dry shifts…
Zvaigžņotā Debess: 2008, Rudens
2008
Latvijas Zinātņu akadēmija, Latvijas Universitāte
Zvaigžņotā Debess: 2007/08, Ziema
2007
Latvijas Zinātnes padome, Latvijas Universitāte
Zvaigžņotā Debess: 2008/09, Ziema
2008
Latvijas Zinātņu akadēmija, Latvijas Universitāte
Linguistica Lettica, Nr. 19
2010
Lavoro a termine e contrattazione collettiva
2014
Nel ripercorrere l’evoluzione della disciplina del lavoro a tempo determinato, considerato come emblema della flessibilità e, al contempo, quale strumento per favorire l’incremento dell’occupazione, l’A. analizza in particolare il ruolo svolto dalla contrattazione collettiva, che talvolta è destinataria di un ampio rinvio legale, talaltra si ritrova ad operare entro ristretti limiti. Analysing the evolution and the regulation of fixed-term contract, considered as a symbol of flexibility and, at the same time, as a means to increase employment, the Author particularly examines the role played by collective bargaining, that sometimes is connected to a large legal referral, sometimes has to op…