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退火对银膜反射率的影响

光学技术 1985年第1期 18-19页

作者： k.p.vijayakumar ,C.purushothaman ,王显厚

一、引言退火对于银膜结构的影响,已经被人们广泛地研究。大家观察到的结果,主要是在薄膜表面会出现凝结成团或发生异常变态——小丘的生长。凝结成团的尺寸,随温度增加而加大,当温度达到一个特殊的数值,即0.59T时,小丘的尺寸达到最大... 详细信息

一、引言退火对于银膜结构的影响,已经被人们广泛地研究。大家观察到的结果,主要是在薄膜表面会出现凝结成团或发生异常变态——小丘的生长。凝结成团的尺寸,随温度增加而加大,当温度达到一个特殊的数值,即0.59T时,小丘的尺寸达到最大值(T代表银的熔融温度)。这种现象过去是用缓慢的结晶位相迁移来说明的。Chopra曾发现温度加热到100℃时,影响最严重。这与Czanderna报导的结果相吻合。根据Hunderi的解释,在薄膜表面发生的这些变化,都可能对银膜的光学特性产生很大影响。本文的目的就在于试验这种变化对银膜光反射

关键词：银膜偏振光非自然光线反射比率反射率银原子

Frequency Control Approach and Load Forecasting Assessment for Wind Systems

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Intelligent Automation & Soft Computing 2023年第1期35卷 971-982页

作者： k.Sukanya p.vijayakumar Department of EEE Karpagam College of EngineeringCoimbatore641032India

Frequency deviation has to be controlled in power generation units when there arefluctuations in system *** several renewable energy sources,wind energy forecasting is majorly focused in this work which is a tough task due to its variations and uncontrollable *** there is a mismatch between generation and demand,the frequency deviation may arise from the actual frequency 50 Hz(in India).To mitigate the frequency deviation issue,it is necessary to develop an effective technique for better frequency control in wind energy *** this work,heuristic Fuzzy Logic Based Controller(FLC)is developed for providing an effective frequency control support by modeling the complex behavior of the system to enhance the load forecasting in wind based hybrid power *** control is applied to reduce the frequency deviation due tofluctuations and load prediction information using ANN(Artificial Neural Network)and SVM(Support Vector Machine)learning *** performance analysis of the proposed method is done with different machine learning based *** forecasting assessment is done over various climates with the aim to decrease the prediction errors and to demote the forecasting *** results show that the Mean Absolute percentage Error(MApE),Root Mean Square Error(RMSE)and Normalized Mean Absolute Error(NMAE)values are scaled down by 41.1%,9.9%and 23.1%respectively in the proposed method while comparing with existing wavelet and BpN based approach.

关键词： Load forecasting wind power prediction fuzzy logic controller ANN SVM hybrid power systems

pV based water pumping system for agricultural irrigation

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Frontiers in Energy 2016年第3期10卷 319-328页

作者： T A BINSHAD k vijayakumar M kALEESWARI Department of Electrical Engineering Malaviya National Institute of Technology Jaipur 302017 India Department of Electrical Engineering Poomima University Jaipur302017 India

This paper investigates the operation and analysis of the photovoltaic water pumping system in detail. power electronic controllers were designed and developed for the water pumping system using a boost converter along with an inverter followed by an induction motor pump set. The proposed system could be employed in agricultural irrigation under any operating condition of varying natures of solar irradiances and temperatures. The configuration and implementation of the system were described in detail. Further, the detailed method of analysis and simulation characteristics of such pV water pumping system was also presented. With the concern of shortage of fossil fuel, global warming and energy security, the proposed pV based water pumping significant demand of electricity agricultural sector. system can meet the and serve for the

关键词： photovoltaic water pumping system power electronic controller solar irradiances and temperature

Exponential gravitational search algorithm-based VM migration strategy for load balancing in cloud computing

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International Journal of Modeling, Simulation, and Scientific Computing 2018年第1期9卷 96-124页

作者： vijayakumar polepally k.Shahu Chatrapati Department of Computer Science and Engineering kakatiya Institute of Technology and Science Warangal TelanganaIndia Department of Computer Science and Engineering JNTUH College of Engineering Manthani KarimnagarTelanganaIndia

With the advancement in the science and technology,cloud computing has become a recent trend in environment with immense requirement of infrastructure and *** balancing of cloud computing environments is an important matter of *** migration of the overloaded virtual machines(VMs)to the underloaded VM with optimized resource utilization is the effective way of the load *** this paper,a new VM migration algorithm for the load balancing in the cloud is *** migration algorithm proposed(EGSA-VMM)is based on exponential gravitational search algorithm which is the integration of gravitational search algorithm and exponential weighted moving average *** our approach,the migration is done based on the migration cost and *** experimentation of proposed EGSA-based VM migration algorithm is compared with ACO and *** simulation of experiments shows that the proposed EGSA-VMM algorithm achieves load balancing and reasonable resource utilization,which outperforms existing migration strategies in terms of number of VM migrations and number of SLA violations.

关键词： Cloud computing load balancing VM migration strategy exponential gravitational search algorithm exponential weighted moving average

Cyathula prostrata:A potent source of anticancer agent against daltons ascites in Swiss albino mice

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Asian pacific Journal of Tropical Medicine 2013年第10期6卷 776-779页

作者： priya k krishnakumari S vijayakumar M pSG College of Arts and Science kongunadu Arts and Science College Institute of Biological Science Faculty of ScienceUniversity of Malaya

Objective:To evaluate the anticancer activity of the methanolic extract of Cyathula prostrata in Ehrlich ascites carcinoma(EAC)-bearing mice with methotrexate as positive control in the advanced stage of ***:EAC was induced in swiss albino mice by injecting10~6 cell/mL of tumor cell suspension *** methanolic extract of Cyathula prostrata effect on the tumor cell viability,DNA fragmentation and MTT assay were carried ***:Methanolic extract attenuated percentage increased in the cell survival lime when compared to control ***,the effect was less than that of *** and the extracts reversed the tumor-induced alterations in UNA fragmentation and MTT ***:The present study suggests that the methanol extract of Cyathula prostrata has significant anticancer activity and that is comparable to that of methotrexate.

关键词： Antitumor Cyathula prostrata MTT Cancer Ehrlich ascites carcinoma

Optimization of Cognitive Femtocell Network via Oppositional Beetle Swarm Optimization Algorithm

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Intelligent Automation & Soft Computing 2023年第4期36卷 819-832页

作者： k.Rajesh kumar M.vijayakumar Department of ECE Adhiyamaan College of EngineeringHosurTamilnaduIndia Department of EEE K.S.R.College of EngineeringTiruchengodeTamilnaduIndia

In past decades,cellular networks have raised the usage of spectrum resources due to the victory of mobile broadband *** devices create massive data than ever before,facing the way cellular networks are installed pre-sently for satisfying the increased trafﬁc *** development of a new exclusive spectrum offered to meet up the trafﬁc requirements is challenging as spectrum resources are limited,hence *** radio technology is pre-sented to increase the pool of existing spectrum resources for mobile users via Femtocells,placed on the top of the available macrocell network for sharing the same ***,the concurrent reuse of spectrum resources from Femto networks poses destructive interference on macro *** resolve this issue,this paper introduces an optimal channel allocation model using the Oppo-sitional Beetle Swarm Optimization Algorithm(OBSOA)to allocate the channel with interference avoidance.A new OBSOA is derived in this paper by the inclu-sion of opposition-based learning(OBL)in *** algorithm allocates the channels used by pUs(pUs)to the secondary users(SUs)in such a way that inter-ference is *** proposed approach is implemented in the MATrix LABoratory(MATLAB)*** performance of this proposed approach is evaluated in terms of several measures and the experimental outcome veriﬁed the superior nature of the OBSOA-based channel allocation *** mod-el has resulted in a maximum signal-to-interference-plus-noise ratio value of 86.42 dB.

关键词： Femto networks channel allocation spectrum reuse cognitive network

Bio Caryota Fiber Reinforced polymer Composites: Mechanical properties and Vibration Behavior Analysis

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Journal of Bionic Engineering 2019年第3期16卷 480-491页

作者： kayaroganam palanikumar vijayakumar Subbiah Department of Mechanical Engineering Sri Sai Ram Institute of Technology Chennai Tamil Nadu India Department of Mechanical Engineerings Sathyabama Institute of Science and Technology Chennai Tamil Nadu India

polymer composites reinforced with the biofibers are found to have improved applications in many fields and also they can reduce the environmental effect. In this work, caryota-a new natural fiber for polymer composites is fabricated and their tensile, flexural and impact properties are estimated to be used in economical and lightweight load carrying structures. Laminates at different weight fraction (wt%) of 10 wt%, 20 wt%, 25 wt%, 30 wt%, 35 wt%, 40 wt% and 45 wt% are manufactured using a compression molding technique. Results asserted that the unidirectional arrangement having 40 wt% fiber posses good properties. Also the dynamic characteristics such as natural frequency and damping study are carried out for different wt% of unidirectional caryota fiber reinforced composite laminates by ex? perimental modal analysis. From this study, it has been asserted that by using the caryota fiber reinforced polyester composites, the traditional synthetic fiber can be replaced especially in automobile sector. If the caryota fiber reinforced composite material is applied properly, then its application fields will be improved.

关键词： natural fiber caryota fiber reinforcements polymer-matrix composites (pMCs) mechanical properties vibration analysis

Simultaneous Enhancement of Transparent and Antibacterial properties of ZnO Films by Suitable F Doping

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Journal of Materials Science & Technology 2015年第7期31卷 759-765页

作者： S.Snega k.Ravichandran M.Baneto S.vijayakumar post Graduate & Research Department of physics AVVM Sri Pushpam College(Autonomous) CUER-UL Universite de LomeFaculte Des Sciences post Graduate & Research Department of Botany and Microbiology AVVM Sri Pushpam College(Autonomous)

Undoped and fluorine doped ZnO （ZnO：F） thin films were deposited onto glass substrates by employing a simplified spray pyrolysis technique using a perfume atomizer. The fluorine doping level in the starting solution was varied from 0 to 20 at.% in steps of 5 at.~g and the effects of fluorine doping level on the structural, optical, surface morphological properties along with their antibacterial activity against Escherichia coil （E. coli） and Bacillus subtilis （B. subtilis） bacteria were studied and reported. The X-ray diffraction studies revealed that despite the orientation ofcrystallites was strongly influenced by fluorine doping, the preferential orientation was retained in favor of （002） plane even at the highest doping level. The crystallite size decreased as the F doping level was increased and the reason for this variation has been explained on the basis of Zener pinning effect. The average optical transparency in the visible range was about 80%-90g for doped films and the optical band gap was found to be slightly increased with the F doping level. The antibacterial efficiency of the F doped ZnO films was found to be enhanced as the F doping level was increased. The antibacterial efficiency was more pronounced in the case of B. subtilis （Gram-positive） when compared with E. coil （Gram-negative）.

关键词： ZnO filmAntibacterial activitySpray pyrolysisDoping

Electrical and non-linear optical studies on electrospun ZnO/BaO composite nanofibers

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Frontiers of Materials Science 2012年第1期6卷 69-78页

作者： G.NIXON SAMUEL vijayakumar M.RATHNAkUMARI p.SURESHkUMAR Department of physics R.M.K.Engineering CollegeR.S.M.NagarKavaraipettai 601206India Materiais Research Centre Department of PhysicsVelammal Engineering CollegeChennai 600066India

Nanocapacitors and nonvolatile ferroelectric random access memories require nanoscale thin film coatings with ferroelectric properties. One dimensional ferroelectric nanofibers are used in ferroelectric memory devices owing to the fact that decrease of the dimensionality of the memory device elements will reduce the addressing and appreciably increase the storage capacity, Novel ZnO/BaO nanocomposite fibers exhibiting ferroelectric properties have been prepared in the form of non-woven mesh by electrospinning the sol derived from the sol-gel route, Thin cylindrical nanofibers of average diameter 100 nm have been obtained and their morphology is confirmed by SEM and AFM images. In the electrospinning process, the effect of the working distance on the fiber morphology was studied and it showed that working distance between 11 and 15 cm can produce fibers without beads and the decrease in working distance in this range increases the fiber diameter. powder XRD was used to identify the phases and EDX analysis confirmed the presence of ZnO/BaO. Dielectric and non-linear optical properties have also been studied. The dielectric studies showed that ZnO/BaO composite nanofibers undergo a phase transition from ferroelectric to paraelectric at 323 k.

关键词： nanocomposite fiber sol-gel process dielectric property non-linear opticalproperty ferroelectric property