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1.
Martinez-Yelmo Isaias Alvarez-Horcajo Joaquin Briso-Montiano Miguel Lopez-Pajares Diego Rojas Elisa 《Telecommunication Systems》2019,72(4):555-565
Telecommunication Systems - The Software-Defined Networking (SDN) architecture decouples the control plane from the data plane, but it does not explicitly state where the control should be located.... 相似文献
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Scientometrics - Short communications are an integral part of academic journal publishing since they serve as a forum for scholarly debate on recently published journal articles. Their prestige and... 相似文献
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Mohsen Karimzadeh Kiskani Zheng Wang Hamid R. Sadjadpour Jose A. Oviedo Jose Joaquin Garcia‐Luna‐Aceves 《Wireless Communications and Mobile Computing》2015,15(14):1837-1850
A new approach for multiantenna broadcast channels in cellular networks based on multiuser diversity concept is introduced. The technique called opportunistic interference management achieves dirty paper coding capacity asymptotically with minimum feedback required. When there are K antennas at the base station with M mobile users in the cell, the proposed technique only requires K integer numbers related to channel state information between mobile users and base station. The encoding and decoding complexity of this scheme is the same as that of point‐to‐point communications, which makes the implementation of this technique easy. An antenna selection scheme is proposed at the base station to reduce the minimum required mobile users significantly at the expense of reasonable increase in feedback. In order to guarantee fairness, a new algorithm is presented that incorporates opportunistic interference management into existing Global System for Mobile communications (GSM) standard. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Joaquin Ramirez Adaikkappan Periyakaruppan Shubhashish Sarkar Govindarajan T Ramesh S. Chidananda Sharma 《Microgravity science and technology》2014,25(5):303-309
Gravity supports all the life activities present on earth. Microgravity environments have effect on the biological functions and physiological status of an individual. The present study was undertaken to investigate the effect of simulated microgravity on important regulatory enzymes of carbohydrate metabolism in liver using HLS mice model. Following hind limb unloading of mice for 11 days the animal’s average body weights were found to be not different, while the liver weights were decreased and found to be significantly different (p < 0.05) from control mice. Further, in liver the specific activity of hexokinase enzyme was reduced (p < 0.02) and the phosphoenolpyruvate carboxykinase activity was significantly increased in simulated microgravity subjected mice compared to control (p < 0.003). Immunoblot analysis show decreased phosphofructokinase-2 activity in HLS mice compared to control. Liver lactate dehydrogenase activity significantly reduced in simulated microgravity subjected mice (p < 0.005). Thus in our study the rodents have adapted to simulated microgravity conditions, with decreased glycolysis and increased gluconeogenesis in liver and reciprocally regulated. 相似文献
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In the last years the amount of information being transmitted through communication networks has increased, and this has lead to an increased use of security protocols. The implementations of security protocols do not accurately follow the standards and this causes many malfunctions and security flaws. In this paper we will analyze the different approaches followed by the scientific community to evaluate security protocols' implementations, and will also analyze the special characteristics of security protocols, in order to deduce which are the key points for such an evaluation, how they can be evaluated and also if existing evaluation techniques can be used. 相似文献
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Mari Pau Balaguer Joaquin Gomez-EstacaJosep Pasqual Cerisuelo Rafael GavaraPilar Hernandez-Munoz 《LWT》2014
In this work a new methodology based on thermo-pressing a resin made from gliadins and glycerol has been developed to obtain water resistant films. The effect of processing temperature was studied on the functional properties of the films. The results of SDS-PAGE analysis of the molecular weight profiles of the resulting films were indicative of disulfide/sulfhydryl interchange reactions giving rise to the formation of intermolecular disulfide bonds between the gliadin units. These reactions augmented the degree of cross-linking of the matrix, which increased with thermo-pressing temperature, as evidenced by the residual reaction enthalpy values determined by MDSC as well as by cross-linking density values determined from tensile tests. In consequence the films produced at high temperature had better water resistance upon immersion, greater maximum tensile strength and Young's modulus values, and lower water vapor and oxygen permeabilities compared with cast films. Based on the analytical test results, thermo-pressing the resin in successive time/force steps along with a temperature of 130 °C produced gliadin films with improved properties. 相似文献
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Maria M Velencoso Agustin SB Gonzalez Joaquin C García‐Martínez Maria J Ramos Antonio De Lucas Juan F Rodriguez 《Polymer International》2013,62(5):783-790
A simple strategy for the synthesis and functionalization of polyurethanes is described. Anionic ring‐opening polymerization was combined with ‘click’ chemistry to synthesize polyols with fluorescent properties. This route allows the incorporation of a wide range of functionalities in the polyols with an easy, clean and highly selective process compatible with several types of functional groups. The proposed strategy opens the way to the production, in a cost‐effective way, of ‘smart’ polyurethanes with non‐conventional properties like fire retardancy, antimite properties, antibacterial properties, etc. Alkynyl groups were introduced into the polyol chains by the controlled addition of glycidyl propargyl ether as co‐monomer during a conventional anionic ring‐opening copolymerization with propylene oxide. Subsequently 4‐azidomethyl‐7‐methoxycoumarin molecules were introduced onto the alkynyl‐polyether polyols by copper‐catalysed cycloaddition reactions to produce end‐functionalized polyols. The chemical structure of the novel polyols was characterized using infrared spectroscopy, nuclear magnetic resonance spectroscopy, gel permeation chromatography with triple detection and matrix‐assisted laser desorption/ionization time‐of‐flight mass spectroscopy. These characterization techniques confirmed the presence of a considerable amount of functional groups in the structure of the polyols. Finally, various fluorescent rigid foams, based on the functionalized polyols, were synthesized. Copyright © 2012 Society of Chemical Industry 相似文献
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Smoke-free policies have been an important tobacco control intervention. As recently as 20 years ago, few communities required workplaces and hospitality venues to be smoke-free, but today approximately 11% of the world's population live in countries with laws that require these places to be smoke-free. This paper briefly summarises important milestones in the history of indoor smoke-free policies, the role of scientific research in facilitating their adoption, a framework for smoke-free policy evaluation and industry efforts to undermine regulations. At present, smoke-free policies centre on workplaces, restaurants and pubs. In addition, many jurisdictions are now beginning to implement policies in outdoor areas and in shared multiunit housing settings. The future of smoke-free policy development depends on credible scientific data that documents the health risks of secondhand smoke exposure. Over the next 20 years smoke-free policies will very likely extend to outdoor and private areas, and changes in the types of tobacco products that are consumed may also have implications for the nature and scope of the smoke-free policies of the future. 相似文献