检索结果-南通市图书馆

Video Transmission secrecy Improvement Based on Fractional Order Hyper Chaotic system

在线全文

学校读者我要写书评

暂无评论

Computer systems science & Engineering 2023年第7期46卷 1201-1214页

作者： s.Kayalvizhi s.malarvizhi Department of Electronics and Communication Engineering SRM Institute of Science and TechnologyKattankulathur603203India

In the Digital World scenario,the confidentiality of information in video transmission plays an important *** systems have been shown to be effective for video signal *** improve video transmission secrecy,compressive encryption method is proposed to accomplish compression and encryption based on fractional order hyper chaotic system that incorporates Compressive sensing(Cs),pixel level,bit level scrambling and nucleotide sequences *** measurement matrix generates by the fractional order hyper chaotic system strengthens the efficiency of the encryption *** avoid plain text attack,the Cs measurement is scrambled to its pixel level,bit level scrambling decreases the similarity between the adjacent measurements and the nucleotide sequence operations are done on the scrambled bits,increasing the *** stages are comprised in the reconstruction technique,the first stage uses the intra-frame similarity and offers robust preliminary retrieval for each frame,and the second stage iteratively improves the efficiency of reconstruction by integrating inter frame Multi Hypothesis(MH)estimation and weighted residual sparsity *** each iteration,the residual coefficient weights are modified using a mathematical approach based on the MH predictions,and the split Bregman iteration algorithm is defined to resolve weighted l1 *** findings show that the proposed algorithm provides good compression of video coupled with an efficient encryption method that is resistant to multiple attacks.

关键词： Fractional order hyper chaotic system compressive sensing pixel level scrambling bit level scrambling nucleotide sequences

Experimental and numerical investigation on under-water friction stir welding of armour grade AA2519-T87 aluminium alloy

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2016年第4期12卷 324-333页

作者： s.sREE sABARI s.malarvizhi V.BALAsUBRAMANIAN G.MADUsUDHAN REDDY Centre for Materials Joining and Research (CEMAJOR) Department of Manufacturing Engineering Annamalai University Metal Joining section Defense Metallurgical Research Laboratory (DMRL)

Friction stir welding(FsW) is a promising welding process that can join age hardenable aluminium alloys with high joint efficiency. However,the thermal cycles experienced by the material to be joined during FsW resulted in the deterioration of mechanical properties due to the coarsening and dissolution of strengthening precipitates in the thermo-mechanical affected zone(TMAZ) and heat affected zone(HAZ). Under water friction stir welding(UWFsW) is a variant of FsW process which can maintain low heat input as well as constant heat input along the weld line. The heat conduction and dissipation during UWFsW controls the width of TMAZ and HAZ and also improves the joint properties. In this investigation, an attempt has been made to evaluate the mechanical properties and microstructural characteristics of AA2519-T87 aluminium alloy joints made by FsW and UWFsW processes. Finite element analysis has been used to estimate the temperature distribution and width of TMAZ region in both the joints and the results have been compared with experimental results and subsequently correlated with mechanical properties.? 2016 China Ordnance society. Production and hosting by Elsevier B.V. All rights reserved.

关键词： Aluminium alloy Friction stir welding Underwater friction stir welding Mechanical properties Microstructural characteristics Finite element analysis

Effect of welding processes on AA2219 aluminium alloy joint properties

在线全文

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals society of China 2011年第5期21卷 962-973页

作者： s.malarvizhi V.BALAsUBRAMANIAN Centre for Materials Joining & Research(CEMAJOR) Department of Manufacturing EngineeringAnnamalai UniversityAnnamalai Nagar 608002India

AA2219 aluminium alloy square butt joints without filler metal addition were fabricated using gas tungsten arc welding （GTAW）, electron beam welding （EBW） and friction stir welding （FsW） processes. The effects of three welding processes on the tensile, fatigue and corrosion behaviour were studied. Microstructure analysis was carried out using optical and electron microscopes. The results show that the FsW joints exhibit superior tensile and fatigue properties compared to EBW and GTAW joints. It is also found that the friction stir welds show lower corrosion resistance than EB and GTA welds. This is mainly due to the presence of finer grains and uniform distribution of strengthening precipitates in the weld metal of FsW joints.

关键词： AA2219 aluminium alloy gas tungsten arc welding electron beam welding friction stir welding tensile properties fatigue properties pitting corrosion

Effect of welding processes on mechanical and microstructural characteristics of high strength low alloy naval grade steel joints

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2015年第3期11卷 308-317页

作者： s.RAGU NATHAN V.BALAsUBRAMANIAN s.malarvizhi A.G.RAO Department of Manufacturing Engineering Annamalai University Centre for Materials Joining & Research (CEMAJOR) Department of Manufacturing EngineeringAnnamalai University Naval Materials Research Laboratory (NMRL)

Naval grade high strength low alloy(HsLA) steels can be easily welded by all types of fusion welding processes. However, fusion welding of these steels leads to the problems such as cold cracking, residual stress, distortion and fatigue damage. These problems can be eliminated by solid state welding process such as friction stir welding(FsW). In this investigation, a comparative evaluation of mechanical(tensile, impact,hardness) properties and microstructural features of shielded metal arc(sMA), gas metal arc(GMA) and friction stir welded(FsW) naval grade HsLA steel joints was carried out. It was found that the use of FsW process eliminated the problems related to fusion welding processes and also resulted in the superior mechanical properties compared to GMA and sMA welded joints.

关键词：低合金高强度钢焊接工艺钢接头组织结构力学性能搅拌摩擦焊机械特性焊接方法

Electrochemical corrosion behaviour of stir zone of friction stir welded dissimilar joints of AA6061 aluminium-AZ31B magnesium alloys

在线全文

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals society of China 2017年第10期27卷 2181-2192页

作者： R.KAMAL JAYARAJ s.malarvizhi V.BALAsUBRAMANIAN Centre for Materials Joining and Research (CEMAJOR) Department of Manufacturing EngineeringAnnamalai University Annamalai Nagar 608002 Tamil Nadu India

Joining of dissimilar metals will offer many advantages in transportation sectors such as fuel consumption,weightreduction and emission ***,joining of aluminium(Al)alloys with magnesium(Mg)alloys by fusion welding processis very *** stir welding(FsW)is a feasible method to join these two dissimilar *** these two metalstogether in stir zone(sZ)leads to poor corrosion *** this investigation,an attempt has been made to understand thecorrosion resistance of sZ of FsWed dissimilar joints of AA6061Al alloy and AZ31B Mg *** polarization testwas conducted by varying chloride ion concentration,pH value of the NaCl solution and exposure *** corroded surfaces wereanalyzed using optical microscopy,scanning electron microscopy and XRD *** these three factors investigated,exposuretime is found to be the most significant factor to influence the corrosion behaviour of sZ of friction stir welded dissimilar joints ofAl/Mg alloys.

关键词： friction stir welding aluminium alloy magnesium alloy dissimilar joint corrosion behaviour

Application of response surface methodology to maximize tensile strength and minimize interface hardness of friction welded dissimilar joints of austenitic stainless steel and copper alloy

在线全文

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals society of China 2013年第8期23卷 2250-2259页

作者： G. VAIRAMANI T. sENTHIL KUMAR s. malarvizhi V. BALAsUBRAMANIAN Department of Mechanical Engineering Seshasayee Institute of Technology Department of Mechanical Engineering Anna University of ChennaiTiruchirappalli Campus Centre for Materials Joining & Research (CEMAJOR) Department of Manufacturing EngineeringAnnamalai University

An attempt was made to optimize friction welding parameters to attain a minimum hardness at the interface and a maximum tensile strength of the dissimilar joints of AIsI 304 austenitic stainless steel （Ass） and copper （Cu） alloy using response surface methodology （RsM）. Three-factor, five-level central composite design matrix was used to specify experimental conditions. Twenty joints were fabricated using Ass and Cu alloy. Tensile strength and interface hardness were measured experimentally. Analysis of variance （ANOVA） method was used to find out significant main and interaction parameters and empirical relationships were developed using regression analysis. The friction welding parameters were optimized by constructing response graphs and contour plots using design expert software. The developed empirical relationships can be effectively used to predict tensile strength and interface hardness of friction welded Ass-Cu joints at 95% confidence level. The developed contour plots can be used to attain required level of optimum conditions to join Ass-Cu alloy by friction welding process.

关键词： friction welding austenitic stainless steel copper alloy tensile strength interface hardness response surface methodology

Efficient Energy-Aware Resource Management Model(EEARMM)Based Dynamic VM Migration

在线全文

学校读者我要写书评

暂无评论

Computer systems science & Engineering 2022年第11期43卷 657-669页

作者： V.Roopa K.malarvizhi s.Karthik Department of Information Technology Sri Krishna College of TechnologyCoimbatore641042India Department of Electrical&Electronics Engineering Kumaraguru College of TechnologyCoimbatore641049India Department of Computer science&Engineering SNS College of TechnologyCoimbatore641035TamilnaduIndia

In cloud environment,an efficient resource management establishes the allocation of computational resources of cloud service providers to the requests of users for meeting the user’s *** proficient resource management and work allocation determines the accomplishment of the cloud ***,it is very difficult to persuade the objectives of the Cloud service Providers(CsPs)and end users in an impulsive cloud domain with random changes of workloads,huge resource availability and complicated service policies to handle them,With that note,this paper attempts to present an Efficient Energy-Aware Resource Management Model(EEARMM)that works in a decentralized ***,the model involves in reducing the number of migrations by definite workload management for efficient resource *** is,it makes an effort to reduce the amount of physical devices utilized for load balancing with certain resource and energy consumption management of every *** Estimation Model Algorithm(EMA)is given for determining the virtual machine ***,VM-selection Algorithm(sA)is also provided for choosing the appropriate VM to migrate for resource *** the incorporation of these algorithms,overloading of VM instances can be avoided and energy efficiency can be improved *** performance evaluation and comparative analysis,based on the dynamic workloads in different factors provides evidence to the efficiency,feasibility and scalability of the proposed model in cloud domain with high rate of resources and workload management.

关键词： Resource management model energy efficient cloud computing VM migration workload management

Optimizing the micro-arc oxidation (MAO) parameters to attain coatings with minimum porosity and maximum hardness on the friction stir welded AA6061 aluminium alloy welds

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2017年第2期13卷 111-117页

作者： R. Kamal Jayaraj s. malarvizhi V. Balasubramanian Centre for Materials Joining and Research(CEMAJOR) Department of Manufacturing EngineeringAnnamalai UniversityAnnamalai Nagar608 002Tamil NaduIndia

Micro-arc oxidation(MAO) technique is capable of producing dense oxide films on the aluminium alloy surface. This oxide film protects the aluminium alloy from the corrosion attack for longer *** relationships were derived to evaluate the MAO coating properties(porosity and hardness) by incorporating very important MAO parameters(current density, inter-electrode distance and oxidation time). MAO parameters were also optimized to achieve coatings with minimum porosity and maximum hardness. Further, the effect of MAO parameters on coating characteristics was analysed. From the results, it is found that the current density has greater influence on the responses than the other two parameters.

关键词： Micro-arc oxidation Aluminium alloy Friction stir weld Response surface methodology

Efficient Approach for Resource Allocation in WPCN Using Hybrid Optimization

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2022年第7期72卷 1275-1291页

作者： Richu Mary Thomas.malarvizhi subramani Department of Electronics and Communication Engineering SRMISTKattankulathur603203India

The recent aggrandizement of radio frequency(RF)signals in wireless power transmission combined with energy harvesting methods have led to the replacement of traditional battery-powered wireless networks since the blooming RF technology provides energy renewal of wireless devices with the quality of service(Qos).In addition,it does not require any unnecessary alterations on the transmission hardware side.A hybridized global optimization technique uniting Global best and Local best(GL)based particle swarm optimization(PsO)and ant colony optimization(ACO)is proposed in this paper to optimally allocate resources in wireless powered communication networks(WPCN)through coordinated operation of communication groups,in which the wireless energy transfer and information sharing take place concomitantly by the aid of a cooperative relay positioned in between the communicating *** designed algorithm assists in minimizing power consumption and maximizes the weighted sum rate at the end-user *** the principal target of the system is coordinated optimization of energy beamforming along with time and energy allocation to reduce the total energy consumed combined with assured information rates of the communication *** outputs are presented to manifest the proposed system’s performance to verify the analytical results via simulations.

关键词： Wireless powered communication networks cooperative communication relay hybrid optimization technique ant colony optimization particle swarm optimization