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Mohammad Reza Parsaei Hamid Reza Boveiri Reza Javidan Raouf Khayami 《International Journal of Communication Systems》2020,33(11)
Telemedicine is a new area based on the information and communication technology for collecting, storing, organizing, retrieving and exchanging medical information. One of the most important applications of telemedicine is indeed telesurgery in which an efficient telecommunication infrastructure between the surgery room and remote surgeons need to be established. One of the most important issues to be tackled in telesurgery is to find favorable links for routing as well as providing high Quality of Service (QoS). In this paper, an efficient model based on the hybridization of Type‐2 Fuzzy System (T2FS) and Cuckoo Optimization Algorithm (COA) over the Software Defined Networks (SDN) is proposed in order to achieve optimal and reliable routes for telesurgery application. Using T2FS, the fitness of the links is determined; then, a COA is conducted over the Constraint Shortest Path (CSP) problem to find the best routes. Delay is considered as a CSP problem which is satisfied by trying to find the paths with minimum cost. Due to the NP‐completeness of the CSP problem, an Enhanced COA (so‐called E‐COA) is proposed and utilized as a metaheuristic solver. To the best of our knowledge, this paper is the first SDN‐based communication model that applies both T2FS and E‐COA for assigning proper costs to the network's links, and solves the consequence CSP problem according to the QoS requirement for telesurgery. The model also recognizes and preserves the second‐best routes in order to keep the reliability for such a critical application. In addition to the simulations, the performance evaluation is also conducted on a real experimental scenario. Many comparisons are carried out between the proposed model and other conventional methods, and the evaluation study shows the superiority of the proposed model on all the three QoS‐related metrics, i.e. average end‐to‐end delay, packet loss ratio and PSNR. 相似文献
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YE Xiao-hua ZHANG Fang-di ZHANG Min ZHANG Rui YE Pei-daKey Laboratory of Optical Communication Lightwave Technologies Beijing University of Posts Telecommunications Beijing P.R. China 《中国邮电高校学报(英文版)》2006,13(1):67-83
1Introduction and BackgroundSelf-synchronization acts as a vital role in ultrafastOptical Ti me Division Multiplexing(OTDM)[1~3]packet networks.Self-synchronization is promising toperformpacket-level clock recovery,which i mplementsstreamcapture by detect… 相似文献
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S. Andrieu F. Ferrieu F. Arnaud d'Avitaya 《Applied Physics A: Materials Science & Processing》1989,49(6):719-722
In this paper, we present an analysis of antinomy deposition on silicon in the range of 0.1 to 1 monolayer by in situ spectroscopic ellipsometry. After a careful choice of viewpoint material, ellipsometric measurements are found to be sensitive to small surface perturbations, especially with antimony. In fact, less than a 0.1 monolayer of antimony on silicon at room temperature is detectable. Moreover, a linear dependence of the ellipsometric signal on Sb coverage is observed in the monolayer range. Consequently, the signal versus time variation directly gives the Sb adsorption kinetics on silicon. The saturation to one monolayer of compact antimony on silicon surface is used in order to calibrate the spectra. 相似文献
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采用分子动力学模拟方法模拟了在周期性边界条件下由500个原子构成的液态Mg模型系统的凝固过程,分别考察了在5×10^14 K/s、5×10^13 K/s、1×10^13 K/s 、1×10^12 K/s的冷却速率下液态Mg熔体的凝固行为。模拟结果很好地重现了实验值。模拟中原子间作用势采用FS势,结构分析采用径向分布函数、均方位移、系统总能量分析、H-A键对分析技术等方法。结果表明,当冷却速率为5×10^14 K/s时,系统形成以1541键对为主的非晶态结构;当冷却速率分别为5×10^13 K/s、1×10^13 K/s、1×10^12 K/s时,系统形成以1421、1422键对为主的hcp晶态结构;另外,在快速冷却形成非晶的过程中,大部分bcc结构被保留下来,而在慢冷形成晶态的过程中,大部分bcc结构最终演化形成了hcp结构。 相似文献
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Oodo Masayuki Miura Ryu Hori Teruhisa Morisaki Takayuki Kashiki Kanshiro Suzuki Mikio 《Wireless Personal Communications》2002,23(1):3-14
In the World Radiocommunication Conference 2000 (WRC-2000), use of the 31 GHzand 28 GHz bands was permitted for the fixed service (FS) by using highaltitude platform stations (HAPS) in some countries. This paper examines thesharing and compatibility of the HAPS-based FS with the other services usingthe same and adjacent frequency bands and establishes the conditions of thecoexistence with those services. Feasibility of dynamic channel assignment(DCA) scheme among the different communication systems to facilitate thecoexistence is also studied. 相似文献
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Proximity effects in normal metal/insulator/ferromagnetic semiconductor/superconductor (NM/I/FS/SC) and NM/I/SC/FS junctions are studied based on an extended Blonder-Tinkham-Klapwijk (BTK) theory. It is found that the magnitude of the proximity effects depends to a great extent on the mismatches of the effective mass and band between the FS and SC. For NM/I/FS/SC junction, the transition of the tunneling conductance from “0” to “π” state is determined by the mass, magnetic exchange energy in FS and the thickness of FS. For NM/I/SC/FS junctions, the conductance spectrum is spin-dependent, indicating a local coexistence of weak ferromagnetism and s-wave superconductivity. 相似文献
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