检索结果-南通市图书馆

Examining the Quality Metrics of a Communication Network with Distributed Software-Defined Networking Architecture

在线全文

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2024年第11期141卷 1673-1708页

作者： Khawaja Tahir Mehmood Shahid Atiq Intisar Ali Sajjad Muhammad Majid Hussain Malik M.Abdul Basit department of Electrical Engineering Khwaja Fareed University of Engineering and Information TechnologyRahim Yar Khan64200Pakistan department of telecommunication systems Bahauddin Zakariya UniversityMultan60000Pakistan department of Electrical Engineering University of Engineering and TechnologyTaxila47050Pakistan School of Engineering and Physical Sciences Heriot-Watt UniversityEdinburghEH144ASUK

Software-Defined Networking(SDN),with segregated data and control planes,provides faster data routing,stability,and enhanced quality metrics,such as throughput(Th),maximum available bandwidth(Bd(max)),data transfer(DTransfer),and reduction in end-to-end delay(D(E-E)).This paper explores the critical work of deploying SDN in large-scale Data Center Networks(DCNs)to enhance its Quality of Service(QoS)parameters,using logically distributed control *** is a noticeable increase in Delay(E-E)when adopting SDN with a unified(single)control structure in big DCNs to handle Hypertext Transfer Protocol(HTTP)requests causing a reduction in network quality parameters(Bd(max),Th,DTransfer,D(E-E),etc.).This article examines the network performance in terms of quality matrices(bandwidth,throughput,data transfer,etc.),by establishing a large-scale SDN-based virtual network in the Mininet *** SDN network is simulated in three stages:(1)An SDN network with unitary controller-POX to manage the data traffic flow of the network without the server load management algorithm.(2)An SDN network with only one controller to manage the data traffic flow of the network with a server load management algorithm.(3)Deployment of SDN in proposed control arrangement(logically distributed controlled framework)with multiple controllers managing data traffic flow under the proposed Intelligent Sensing Server Load Management(ISSLM)*** a result of this approach,the network quality parameters in large-scale networks are enhanced.

关键词： Software defined networking quality of service hypertext transfer protocol data transfer rate latency maximum available bandwidth server load management

Texture Feature Extraction from Thyroid MR Imaging Using High-Order Derived Mean CLBP

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Computer Science & Technology 2019年第1期34卷 35-46页

作者： Zhe Liu Cheng-Jian Qiu Yu-Qing Song Xiao-Hong Liu Juan Wang Victor S.Sheng School of Computer Science and telecommunication Jiangsu UniversityZhenjiang 212013China department of Computer Science University of Central ArkansasArkansas 72035U.S.A.

In the field of medical imaging,the traditional local binary pattern (LBP)and its improved algorithms are often sensitive to *** LBPs are solely based on the signal information from local differences,and the binary quantization method oversimplifies the local texture features while disregarding the imaging information from the concaveconvex regions between the high-order pixels and the neighboring sampling ***,we propose an improved Derived Mean Complete Local Binary Pattern (DM_CLBP) algorithm based on high-order *** the DM_CLBP method,the grey value of a single pixel is replaced by the mean grey value of the rectangular area block,and the difference between pixel values in the area is obtained using the second-order differentiation *** on the calculation concept of the complete local binary pattern (CLBP)algorithm,the cascade signs and magnitudes of the two components are encoded and recombined in DM_CLBP using a uniform *** results from the experiments showed that the proposed DM_CLBP descriptors achieved a classification accuracy of 94.4%.Compared with LBP and other improved algorithms,the DM_CLBP algorithm presented in this study can effectively differentiate between lesion areas and normal areas in thyroid MR,(magnetic resonance)images and shows the improved accuracy of area classification.

关键词： thyroid magnetic resonance imaging (MRI) local binary pattern texture feature complete local binary pattern (CLBP)

Multi-Gigabit CO-OFDM System over SMF and MMF Links for 5G URLLC Backhaul Network

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2021年第5期67卷 1747-1758页

作者： Amir Haider MuhibUr Rahman Tayyaba Khan Muhammad Tabish Niaz Hyung Seok Kim department of Intelligent Mechatronics Engineering Sejong UniversitySeoul05006Korea department of Electrical Engineering Polytechnique MontrealMontrealCanada department of telecommunication Engineering University of Engineering and TechnologyTaxila47050Pakistan

The 5G cellular network aims at providing three major services:Massive machine-type communication(mMTC),ultra-reliable low-latency communications(URLLC),and enhanced-mobile-broadband(eMBB).Among these services,the URLLC and eMBB require strict end-to-end latency of 1 ms while maintaining 99.999%reliability,and availability of extremely high data rates for the users,*** of the critical challenges in meeting these requirements is to upgrade the existing optical fiber backhaul network interconnecting the base stations with a multigigabit capacity,low latency and very high reliability *** address this issue,we have numerically analyzed 100 Gbit/s coherent optical orthogonal frequency division multiplexing(CO-OFDM)transmission performance over 400 km single-mode fiber(SMF)and 100 km of multi-mode fiber(MMF)*** system is simulated over optically repeated and non-repeated SMF and MMF *** transmission is used,and the system is analyzed in a linear and non-linear *** system performance is quantified by bit error ratio(BER).Spectrally efficient and optimal transmission performance is achieved for 400 km SMF and 100 km MMF *** results designate thatMMF links can be employed beyond short reach applications by using them in the existing SMF infrastructure for long haul *** particular,the proposed CO-OFDM system can be efficiently employed in 5G backhaul *** multi-gigabit capacity and lower BER of the proposed system makes it a suitable candidate especially for the eMBB and URLLC requirements for 5G backhaul network.

关键词： CO-OFDM coherent transmission spectrally efficient optical communication optical networks dispersion eMBB URLLC 5G backhaul

AN IMPROVED PATTERN OF STAR TYPE LAN HAVING MULTIPLE ACCESS CAPABILITY

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1990年第20期35卷 1740-1744页

作者：逯昭义王思明 department of Electronics Lanzhou University Lanzhou 730070 PRC department of telecommunication Lanzhou Railway Institute Lanzhou 730070 PRC

Ⅰ. ISSUES PUT FORWARDWe have published some reports on a star type LAN which has multiple access capability （LAN1 for short ）. It has the superiority as follows: （ⅰ）The characteristics of topology structure can ... 详细信息

关键词： multiple access capability center-node.

Current Inversion in a Temperature Ratchet with Asymmetric Unbiased External Forces

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2005年第11期22卷 2772-2775页

作者：艾保全谢汇章刘良钢 School of Physics and telecommunication Engineering South China Normal University Guangzhou 510631 department of Physics South China University of Technology Guangzhou 510641 department of Physics Zhongshan University Guangzhou 510275

Transport of a Brownian particle moving in a symmetric potential is investigated in the presence of an asymmetric unbiased external force. The viscous medium is alternately in contact with the two heat reservoirs. We present the analytical expression of the net current at the quasi-steady state limit. It is found that the competition of the temporal asymmetric parameter of the driving force with the temperature difference leads to current reversals. The competition between the two opposite driving factors is a necessary but not a sufficient condition for current reversals.

关键词： CURRENT REVERSAL TRANSPORT EFFICIENCY RESONANCE DRIVEN SYSTEM

Procreating Tiles of Double Commutative-Step Digraphs

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2008年第2期24卷 185-194页

作者： Jian-qin Zhou telecommunication School Hangzhou Dianzi University Hangzhou 310018 China department of Computer Science Anhui University of Technology Ma'anshan 243002 China

Double commutative-step digraph generalizes the double-loop digraph. A double commutative-step digraph can be represented by an L-shaped tile, which periodically tessellates the plane. Given an initial tile L（l, h, x, y）, Aguil5 et al. define a discrete iteration L（p） = L（l ＋ 2p, h ＋ 2p, x ＋ p, y ＋ p）, p = 0, 1, 2,..., over L-shapes （equivalently over double commutative-step digraphs）, and obtain an orbit generated by L（l, h, x,y）, which is said to be a procreating k-tight tile if L（p）（p = 0, 1, 2, ~ ~ ~ ） are all k-tight tiles. They classify the set of L-shaped tiles by its behavior under the above-mentioned discrete dynamics and obtain some procreating tiles of double commutative-step digraphs. In this work, with an approach proposed by Li and Xu et al., we define some new discrete iteration over L-shapes and classify the set of tiles by the procreating condition. We also propose some approaches to find infinite families of realizable k-tight tiles starting from any realizable k-tight L-shaped tile L（l, h, x, y）, 0 ≤ y - x ≤ 2k ＋ 2. As an example, we present an infinite family of 3-tight optimal double-loop networks to illustrate our approaches.

关键词： Double-loop digraph double commutative-step digraph L-shaped tile procreate infinite family

Flicker and thermal noise in an n-channel underlap DG FinFET in a weak inversion region

在线全文

学校读者我要写书评

暂无评论

Journal of Semiconductors 2013年第2期34卷 31-36页

作者： Sudhansu Kumar Pati Hemant Pardeshi Godwin Raj N Mohankumar Chandan Kumar Sarkar Nano Device Simulation Laboratory Electronics and Telecommunication Engineering DepartmentJadavpur University SKP College of Engineering TiruvannamalaiTamilnadu-606 611India

We propose an analytical model for drain current and inversion charge in the subthreshold region for an underlap DG FinFET by using the minimum channel potential method, i.e., the virtual source. The flicker and thermal noise spectral density models are also developed using these charge and current models expression. The model is validated with already published experimental results of flicker noise for DG FinFETs. For an ultrathin body, the degradation of effective mobility and variation of the scattering parameter are considered. The effect of device parameters like gate length Lg and underlap length Lun on both flicker and thermal noise spectral densities are also analyzed. Increasing Lg and Lun, increases the effective gate length, which reduces drain current, resulting in decreased flicker and thermal noise density. A decrease of flicker noise is observed for an increase of frequency, which indicates that the device can be used for wide range of frequency applications.

关键词： flicker noise thermal noise ultrathin body virtual source underlap DG FinFET

Andreev reflection and tunneling spectrum on metal-superconductor-metal junctions

在线全文

学校读者我要写书评

暂无评论

Frontiers of physics 2012年第4期7卷 449-452页

作者： Jiajun Ouyang W.LiMing Liangbin Hu department of Physics and Laboratory of Quantum Information TechnologySchool of Physics and Telecommunication EngineeringSouth China Normal UniversityGuangzhou 510006China

The tunneling spectrum of an electron and a hole in metal superconductor-metal junctions is com- puted using the Blonder-Tinkham Klapwijk method. The incident and the outgoing currents finally balance each other by an interface charge inside the superconductor and metal junction. The present computation shows a more abundant structure compared to that on a metal superconductor junc- tion, such as the resonance at bias voltages above the energy gap of the superconductor. The density of the interface charge shows a quantum-like oscillation.

关键词： Andreev reflection superconductivity

Performance Analysis of 5 G Wireless Hybrid Precoding Using Evolutionary Algorithms

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2023年第5期20卷 2317-2330页

作者： Madhusmita Sahoo Harish Kumar Sahoo department of ECE ITERSiksha O Anusandhan UniversityJagamaraBhubaneswarOdisha751030India department of Electronics and telecommunication Engineering Veer Surendra Sai University of TechnologyBurlaSambalpurOdisha768018India

Emerging 5G communication solutions utilize the millimeter wave(mmWave)band to alleviate the spectrum *** the mmWave range,Multiple Input Multiple Output(MIMO)technologies support a large number of simultaneous *** mmWave MIMO wireless systems,hybrid analog/digital precoding topologies provide a reduced complexity substitute for digital *** Error Rate(BER)and Spectral efficiency performances can be improved by hybrid Minimum Mean Square Error(MMSE)precoding,but the computation involves matrix inversion *** number of antennas at the broadcasting and receiving ends is quite large for mm-wave MIMO systems,thus computing the inverse of a matrix of such high dimension may not be practically *** to the need for matrix inversion and known candidate matrices,the classic Orthogonal Matching Pursuit(OMP)approach will be more *** novelty of research presented in this manuscript is to create a hybrid precoder for mmWave communication systems using metaheuristic algorithms that do not require matrix inversion *** metaheuristic approach has not employed much in the formulation of a precoder in wireless *** distinct evolutionary algorithms,such as Harris–Hawks Optimization(HHO),Runge–Kutta Optimization(RUN),Slime Mould Algorithm(SMA),Hunger Game Search(HGS)Algorithm and Aquila Optimizer(AO)are considered to design optimal hybrid precoder for downlink transmission and their performances are tested under similar practical *** to simulation studies,the RUN-based precoder performs better than the conventional algorithms and other nature-inspired algorithms based precoding in terms of spectral efficiency and BER.

关键词： Millimeter wave Hybrid precoding MIMO HHO HGS RUN SMA.AO