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Implementation of K-Means Algorithm and Dynamic Routing Protocol in VANET

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Computer Systems Science & Engineering 2022年第2期40卷 455-467页

作者： Manoj Sindhwani Charanjeet Singh Rajeshwar Singh School of Electronics and Electrical Engineering Lovely Professional UniversityPhagwara144411India Doaba Group of Colleges Nawanshar144517India

With the growth of Vehicular Ad-hoc Networks,many services delivery is gaining more attention from the intelligent transportation ***,mobility characteristics of vehicular networks cause frequent disconnection of routes,especially during the delivery of *** both developed and developing countries,a lot of time is consumed due to traffic *** has significant negative consequences,including driver stress due to increased time demand,decreased productivity for various personalized and commercial vehicles,and increased emissions of hazardous gases especially air polluting gases are impacting public health in highly populated *** is one of the most powerful strategies for achieving a consistent topological *** algorithms are presented in this research ***,a k-means clustering algorithm in which dynamic grouping by k-implies is performed that fits well with Vehicular network’s dynamic topology *** suggested clustering reduces overhead and traffic ***,for inter and intra-clustering routing,the dynamic routing protocol is proposed,which increases the overall Packet Delivery Ratio and decreases the End-to-End *** to the cluster-based approach,the proposed protocol achieves improved efficiency in terms of Throughput,Packet Delivery Ratio,and End-to-End delay parameters comparing the situations by taking different number of vehicular nodes in the network.

关键词： Cluster head cluster member intelligent transportation system packet delivery ratio vehicular communication

Bandgap characteristics of 2D plasma photonic crystal with oblique incidence:TM case

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Chinese Physics B 2011年第6期20卷 1-6页

作者：谢应涛杨利霞 Department of communication Engnerring Jiangsu University State Key Laboratory of Millimeter Waves Southeast University

A novel periodic boundary condition （PBC）, that is the constant transverse wavenumber （CTW） method, is introduced to solve the time delay in the transverse plane with oblique incidence. Based on the novel PBC, the FDTD/PBC algorithm is proposed to study periodic structure consisting of plasma and vacuum. Then the reflection coefficient for the plasma slab from the FDTD/PBC algorithm is compared with the analytic results to show the validity of our technique. Finally, the reflection coefficients for the plasma photonic crystals are calculated using the FDTD/PBC algorithm to study the variation of bandgap characteristics with the incident angle and the plasma parameters. Thus it has provided the guiding sense for the actual manufacturing plasma photonic crystal.

关键词： finite-difference time-domain method photonic crystal plasma periodic boundary condition

Tracking of Non-Rigid Object in Complex Wavelet Domain

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Journal of Signal and Information Processing 2011年第2期2卷 105-111页

作者： Om Prakash Ashish Khare Department of Electronics & communication University of Allahabad centre of Computer Education University of Allahabad

In this paper we have proposed an object tracking method using Dual Tree Complex Wavelet Transform (DTCxWT). The proposed method is capable of tracking the moving object in video sequences. The object is assumed to be deform-able under limit i.e. it may change its shape from one frame to another. The basic idea in the proposed method is to decompose the image into two components: a two dimensional motion and a two dimensional shape change. The motion component is factored out while the shape is explicitly represented by storing a sequence of two dimensional models. Each model corresponds to each image frame. The proposed method performs well when the change in the shape in the consecutive frames is small however the 2-D motion in consecutive frames may be large. The proposed algorithm is capable of handling the partial as well as full occlusion of the object.

关键词： Object Tracking Dual Tree Complex Wavelet Transform Model Based Tracking Biorthogonal Filters

Stability Conditions of Fuzzy Filter Type III

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Journal of Signal and Information Processing 2011年第3期2卷 245-251页

作者： José de Jesús Medel Juárez Juan Carlos García Infante Juan Carlos Sánchez García centre of Computing Research National Polytechnic Institute professional School of Mechanical and Electrical Engineering National Polytechnic Institute

A digital fuzzy logic filter of type III interacts with a real model signal reference to obtain the best answer in the sense of minimum mean square error of the output. The key part of the filter is a fuzzy mechanism that adaptively selects and emits answer according to the changes of the external reference signal. Based on input signal level, this fuzzy filter selects the best parameter values from a set of membership in the knowledge base (KB), and the filter weights are updated according to the reference signal in a natural form. With this fuzzy structure the filter reduces error. The simulation result shows the stability of the filter. The states of the filtering process require that all of its answers are bounded by the error criteria probabilistically.

关键词： Digital Filtering Fuzzy Systems Estimation Stability

Flexible Uplink MU-MIMO Scheduling in UnlicensedSpectrum

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China communications 2017年第12期14卷 59-71页

作者： Boqi Jia Ting Zhou Honglin Hu Yang Yang Zhenhong Li Sandrine Boumard Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai China Shanghai Advanced Research Institute Chinese Academy of Sciences Shanghai China Shanghai Research Center for Wireless communication Shanghai China TCL communication Technology Holdings Ltd. Shanghai R&D Center Shanghai China VTT Technical Research centre of Finland Ltd Oulu Finland University of Chinese Academy of Sciences Beijing China

Utilizing the unlicensed spectrum as supplementary is being studied to meet the increasingly growing demand of user equipment for rate,traffic and bandwidth,and thus to mitigate the current spectrum scarcity *** this paper,we investigate the uplink multi-user multiple-input multiple-output(UL MU-MIMO) technique to achieve multiplexing gain in unlicensed *** first define a new parameter called channel busy radio(CBR) which is related to the probability of occupying the unlicensed channel,and find that the failure to occupy the unlicensed channel leads to the performance degradation in unlicensed ***,according to the user-specific CBR of the unlicensed channel,we propose a flexible scheduling scheme for UL MU-MIMO in unlicensed spectrum,and formulate an optimization problem for the optimal scheduled user ***,an adaptive scheduling algorithm is proposed to decide the optimal number of the scheduled users *** simulation results show that,based on statistical channel condition in unlicensed spectrum,adjusting the number of the scheduled user flexibly can offset the degraded throughput and form an optimal MU-MIMO transmission.

关键词： 5G unlicensed spectrum MU-MIMO uplink scheduling

Multi-Resources Management in 6G-Oriented Terrestrial-Satellite Network

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China communications 2021年第9期18卷 24-36页

作者： Shu Fu Bibo Wu Shaohua Wu Fang Fang College of Microelectronics and communication Engineering Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Space Information Network and Intelligent Information Fusion Chongqing UniversityChongqing 400044China communication Engineering Research centre Harbin Institute of Technology(Shenzhen)Guangdong 518055China Peng Cheng Laboratory Shenzhen 518055China Department of Engineering Durham UniversityDurham DH13LEU.K

The six-generation(6G)wireless network is expected to satisfy the requirements of ubiquitous connectivity and intelligent *** networks(TSN)enable seamless coverage for terrestrial users in a wide area,making it very promising in *** data traffic in TSNs surges,the integrated management for caching,computing,and communication(3C)has attracted much research *** this paper,we investigate the multi-resource management in the uplink and downlink transmission of TSN,*** particularly,we aim to guarantee both throughput fairness and data security in the uplink transmission of *** the intermittent communication of the satellite,we introduce two kinds of relays,i.e.,terrestrial relays(TRs)and aerial relays(ARs)to improve the system throughput performance in the downlink transmission of ***,we study a specific case of TSN with the uplink and downlink transmission,and the corresponding simulation results validate the effectiveness of our proposed schemes.

关键词： downlink transmission multi-resource management relay terrestrial-satellite networks up-link transmission

A Privacy-Preserving Image Retrieval Based on AC-Coefficients and Color Histograms in Cloud Environment

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Computers, Materials & Continua 2019年第1期58卷 27-43页

作者： Zhihua Xia Lihua Lu Tong Qiu H.J.Shim Xianyi Chen Byeungwoo Jeon Jiangsu Engineering centre of Network Monitoring Jiangsu Collaborative Innovation Center on Atmospheric Environment and Equipment TechnologySchool of Computer and SoftwareNanjing University of Information Science&TechnologyNanjing210044China College of Information&communication Engineering Sungkyunkwan UniversityKorea

Content based image retrieval(CBIR)techniques have been widely deployed in many applications for seeking the abundant information existed in *** to large amounts of storage and computational requirements of CBIR,outsourcing image search work to the cloud provider becomes a very attractive option for many owners with small ***,owing to the private content contained in images,directly outsourcing retrieval work to the cloud provider apparently bring about privacy problem,so the images should be protected carefully before *** paper presents a secure retrieval scheme for the encrypted images in the YUV color *** this scheme,the discrete cosine transform(DCT)is performed on the Y *** resulting DC coefficients are encrypted with stream cipher technology and the resulting AC coefficients as well as other two color components are encrypted with value permutation and position *** the image owner transmits the encrypted images to the cloud *** receiving a query trapdoor form on query user,the server extracts AC-coefficients histogram from the encrypted Y component and extracts two color histograms from the other two color *** similarity between query trapdoor and database image is measured by calculating the Manhattan distance of their respective ***,the encrypted images closest to the query image are returned to the query user.

关键词： Image retrieval AC-coefficients histogram color histogram discrete cosine transform

Formaldehyde gas sensor based on TiO_2 thin membrane integrated with nano silicon structure

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Optoelectronics Letters 2016年第4期12卷 308-311页

作者：郑轩明安杰叶丽陈凤华孙西龙刘卫兵李超波欧文王玮冰陈大鹏 School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of Sciences Smart Sensing Research and Development centre Institute of MicroelectronicsChinese Academy of Sciences Laboratory of Advanced Polymer Materials Institute of ChemistryChinese Academy of Sciences

An innovative formaldehyde gas sensor based on thin membrane type metal oxide of Ti O2 layer was designed and fabricated. This sensor under ultraviolet(UV) light emitting diode(LED) illumination exhibits a higher response to formaldehyde than that without UV illumination at low temperature. The sensitivities of the sensor under steady working condition were calculated for different gas concentrations. The sensitivity to formaldehyde of 7.14 mg/m^3 is about 15.91 under UV illumination with response time of 580 s and recovery time of 500 s. The device was fabricated through micro-electro-mechanical system(MEMS) processing technology. First, plasma immersion ion implantation(PIII) was adopted to form black polysilicon, then a nanoscale TiO_2 membrane with thickness of 53 nm was deposited by DC reactive magnetron sputtering to obtain the sensing layer. By such fabrication approaches, the nanoscale polysilicon presents continuous rough surface with thickness of 50 nm, which could improve the porosity of the sensing membrane. The fabrication process can be mass-produced for the MEMS process compatibility.

关键词： Crystal symmetry Fabrication Formaldehyde Gas detectors Ion implantation MEMS Metals Nanotechnology Plasma applications Polycrystalline materials Polysilicon Temperature Titanium dioxide

Synchronizability of time-varying structured duplex dynamical networks with different intra-layer rewiring mechanisms

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Science China(Technological Sciences) 2022年第2期65卷 375-385页

作者： WU XiaoQun ZHOU Xiong LIU Jie YANG QiRui CHEN Yuan Yuan School of Mathematics and Statistics Wuhan UniversityWuhan 430072China Hubei Key Laboratory of Computational Science Wuhan UniversityWuhan 430072China Research centre of Nonlinear Science Wuhan Textile UniversityWuhan 430073China School of Journalism and communication Hubei University of EconomicsWuhan 430205China

Global synchronizability of duplex networks induced by three different intra-layer rewiring mechanisms is explored in this *** rewiring mechanisms are named as model-preserving rewiring(MPR), simply direct rewiring(SDR), and degree-preserving rewiring(DPR), respectively. It is found that high switching frequencies will certainly enhance global synchronizability for WSWS duplex networks(i.e., each layer is independently formed by the algorithm proposed by Watts and Strogatz for generating small-world networks), ER-ER duplex networks(i.e., each layer is independently generated by the algorithm proposed by Erd ¨os and Renyi) and BA-BA duplex networks(i.e., each layer is independently formed by the classical BA algorithm). Namely,the faster the intra-layer couplings are reconnected, the faster the duplex networks reach global synchronization. Furthermore,we find that by increasing the intra-or inter-coupling strengths, the WS-WS time-varying network’s global synchronizability is enhanced. Take the WS-WS time-varying network as an example, we find that SDR mechanism has greater impact on global synchronizability than MPR mechanism and DPR mechanism. The related dynamical networks can arrive at synchronization faster by SDR than by MPR or DPR. Thus, we only study the effects of SDR on ER-ER duplex networks and BA-BA duplex networks. In addition, we obtain the fact via numerical simulations that, switching intra-layer coupling topologies under SDR mechanism has the greatest impact on the BA-BA duplex network, followed by the ER-ER network, and has the weakest influence on the WS-WS duplex network in terms of improving the global synchronizability when all the intra-layer networks are sparse and have the same average degree. Finally, the global synchronizability of WS-WS and BA-BA time-varying networks is improved compared with static duplex networks, the reason being that the networks tend to be randomized under SDR according to analysis of the networks’ average clus

关键词： multiplex network time-varying networks intra-layer connection synchronizability reconnection