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repellent properties of Cardiospermum,halicacabum Linn.(Family:Sapindaceae)plant leaf extracts against three important vector mosquitoes

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Asian Pacific Journal of Tropical Biomedicine 2012年第8期2卷 602-607页

作者： M Govindarajan r sivakumar Division of Vector Biology and Phytochemistry Department of ZoologyAnnamalai University

Objective:To determine repellent activity of hexane,ethyl acetate,benzene,chloroform and methanol extract of Cardiospermum halicacabum,(***) against Culex quinque/ascialus(***),Aedes aegypti(***) and Anopheles slephensi(***). Methods:Evaluation was carried out in a net cage(45 cm×30 cm×25 cm) containing 100 blood starved female mosquitoes of three mosquito species and were assayed in the laboratory condition by using the protocol of WHO 2005;The plant leaf crude extracts of *** was applied at 1.0,2.5,and 5.0 me/cm^2 separately in the exposed area of the fore *** ethanol served as ***:In this observation,the plant crude extracts gave protection against mosquito bites without any allergic reaction to the test person,and also,the repellent activity was dependent on the strength of the plant *** tested plant crude extracts had exerted promising repellent against all the three ***:From the results it can be concluded the crude extract of *** was potential for controlling ***, *** and *** mosquitoes.

关键词： repellency Cardiospermum halicacabum Culex quinquefasciatus Aedes aegypti Anopheles stephensi

Larvicidal and repellent activity of tetradecanoic acid against Aedes aegypti(Linn.) and Culex quinquejasciatus(Say.)(Diptera:Culicidae)

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Asian Pacific Journal of Tropical Medicine 2011年第9期4卷 706-710页

作者： sivakumar r Jebanesan A Govindarajan M rajasekar P Division of Vector Biology Department of Zoology.Annamalai University.Annamalainagar-608 002.Tamil NaduIndia

Objective:To investigate the larvicidal and repellent efficacy of tetradecanoic acid against Aedes aegrpti（***） L,and Culex quinquefasciatus（***） Say（Diptera: Culicidae）.Methods:Larvicidal efficacy of tetradecanoic acid was tested at various concentrations against the early third instar larvae of *** and ***. The repellent activity was determined against two mosquito species at three concentrations viz..1.***.2.5 and 5.0 ppm under the laboratory ***:The tetradecanoic acid was found to be more effective against *** than *** *** LC50 values were 14.08 ppm and 25.10 ppm,*** acid showed lesser repellency against *** and *** highest repellency was observed in higher concentration of 5.0 mg/cm2 provided 100%protection up to 60 and 90 min against *** and *** ***:From the results it can be concluded the tetradecanoic acid is a potential for controlling *** and *** mosquitoes.

关键词： Tetradecanoic acid Larvicidal activity repellent activity Aedes aegypti Culex quinquefasciatus

Brain Tumor Classification Using Image Fusion and EFPA-SVM Classifier

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Intelligent Automation & Soft Computing 2023年第3期35卷 2837-2855页

作者： P.P.Fathimathul rajeena r.sivakumar Anna University Chennai600025India Department of Computer Science and Engineering Tamilnadu College of EngineeringCoimbatore641659India

An accurate and early diagnosis of brain tumors based on medical ima-ging modalities is of great interest because brain tumors are a harmful threat to a person’s health *** medical imaging techniques have been used to analyze brain tumors,including computed tomography(CT)and magnetic reso-nance imaging(MrI).CT provides information about dense tissues,whereas MrI gives information about soft ***,the fusion of CT and MrI images has little effect on enhancing the accuracy of the diagnosis of brain ***,machine learning methods have been adopted to diagnose brain tumors in recent *** paper intends to develop a novel scheme to detect and classify brain tumors based on fused CT and MrI *** pro-posed approach starts with preprocessing the images to reduce the ***,fusion rules are applied to get the fused image,and a segmentation algorithm is employed to isolate the tumor region from the background to isolate the tumor ***,a machine learning classiﬁer classiﬁed the brain images into benign and malignant *** statistical measures evaluate the classi-ﬁcation potential of the proposed *** outcomes are provided,and the Enhanced Flower Pollination Algorithm(EFPA)system shows that it out-performs other brain tumor classiﬁcation methods considered for comparison.

关键词： Brain tumor classiﬁcation improved wavelet threshold integer wavelet transform medical image fusion

Mosquito larvicidal properties of Ficus henghalensis L.(Family:Moraceae) against Culex tritaeniorhynchus Giles and Anopheles subpictus Grassi(Diptera:Culicidae)

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Asian Pacific Journal of Tropical Medicine 2011年第7期4卷 505-509页

作者： M Govindarajan r sivakumar A Amsath S Niraimathi Division of Vector Biology and phytochemistry Department of ZoologyAnnamalai UniversityAnnamalainagar-608002India PG & research Department of Zoology Khadir Mohideen CollegeAdirampattinam-614701TamilnaduIndia PG & research Department of Biochemistry RVS College of Arts and ScienceKaraikal-609 609TamilnaduIndia

Objective:To determine the larvicidal efficacy of different solvent leaf extract of Ficus benghalensis（***） against Culex tritaeniorhynchus（***） and Anopheles subpictus（***）.Methods:Twenty five early third instar larvae of Cx. tritaeniorhynchus and *** were exposed to various concentrations and were assayed in the laboratory by using the protocol of WHO *** larval mortality was observed after 24 h of ***:Among three solvent extracts tested the maximum efficacy was observed in the methanol *** LC50 and LC90 values of *** against early third instar of Cx. tritaeniorhynchus and *** were 100.***.159.76 ppm and 56.***.85.84 ***. No mortality was observed in *** chi-square values were significant at Prom the results it can be concluded the crude extract of *** was an excellent potential for controlling *** and *** mosquito larvae.

关键词： Larvicidal activity Culex tritaeniorhynchus Anopheles subpictus Finis benghalensis

Preparation of cerium and yttrium doped ZnO nanoparticles and tracking their structural,optical,and photocatalytic performances

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Journal of rare Earths 2023年第5期41卷 682-688,I0002页

作者： Essia Hannachi Yassine Slimani Muhammad Nawaz r.sivakumar Zayneb Trabelsi r.Vignesh Sultan Akhtar Munirah A.Almessiere Abdulhadi Baykal Ghulam Yasin Department of Nuclear Medicine research Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam31441Saudi Arabia Department of Biophysics Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam31441Saudi Arabia Department of Nanomedicine research Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityPO.Box 1982Dammam31441Saudi Arabia Department of Physics Alagappa UniversityKaraikudi630003India Faculty of Sciences of Bizerte University of CarthageZarzouna7021Tunisi Department of Physics College of ScienceImam Abdulrahman Bin Faisal UniversityP0.Box 1982Dammam31441Saudi Arabia State Key Laboratory of Chemical resource Engineering College of Materials Science and EngineeringBeijing University of Chemical TechnologyBejing 100029China Institute for Advanced Study College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China

Yttrium(Y)and cerium(Ce)co-doped ZnO nanoparticles(NPs)were synthesized via the simple sol-gel auto-combustion *** effect of Ce and Y doping on the structure,morphology,optical,Zeta potential,and photocatalytic activities of ZnO NPs was examined by Fourier transform infrared(FTIr)spectrometer,X-ray diffraction(XrD),transmission electron microscope(TEM),UV-vis spectrophotometer,and Zetasizer *** data show that the fabricated samples crystallize into a hexagonal wurtzite *** dopants Y and Ce affect the crystal structure of ZnO *** crystallite size is reduced with the co-doping *** results confirm the nano-sized particles of the prepared *** increase in optical bandgap values from 3.19 eV for x=0.0 to 3.22,3.24,and 3.25 eV for x=0.01,0.03,and 0.05 samples was confirmed by UV-Vis spectroscopy analysis.Y and Ce co-doped ZnO nanoparticles show significant alteration of zeta potential and photocatalytic properties compared to undoped ZnO ***,undoped ZnO shows better stability in deionized water as compared to Ce-Y doped ZnO NPs and exhibits high photocatalytic activity(degradation rate,97.92%)for methyl orange(MO)degradation.

关键词： ZnO nanoparticles Co-doping rare earth Structure Bandgap energy Photocatalytic activity

Evanescent Mode Bandpass Filters for Microwave Communication Systems-A review

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Evanescent Mode Bandpass Filters for Microwave Communication...

Prediction of Better Flow Control Parameters in MHD Flows Using a High Accuracy Finite Difference Scheme

2011 International Conference on Signal,Image Processing and Applications（ICSIA 2011）

作者： G.ramakrishnan r.sivakumar Department of Information Technology R.M.K.Engineering CollegeKavaraipettaiThiruvallur District Department of Electronics and Communication Engineering R.M.K.Engineering CollegeKavaraipettaiThiruvallur District

This paper reviews some of the many published technical papers relating to the design of bandpass filters using Evanescent mode(waveguide below cut-off)technique.A small section of an evanescent mode closely represents lumped *** may be formed by introducing capacitive obstacles in the waveguide and this concept is being used in the design of tunable bandpass *** mode filters have drawn much attention to applications such as air-borne equipment and satellite systems due to the fact that they are light weight and smaller in size compared to conventional *** will follow the development of this methodology from the early investigations through the later applications and see how inductive strips in ridge waveguides would improve the performance of evanescent mode bandpass filters.

关键词： Evanescent,Bandpass,Passband,Stopband,ridge,Substrate,Waveguide.

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American Journal of Computational Mathematics 2017年第3期7卷 243-275页

作者： A. D. Abin rejeesh S. Udhayakumar T. V. S. Sekhar r. sivakumar Department of Physics Pondicherry University Puducherry India School of Basic Sciences Indian Institute of Technology Bhubaneswar Bhubaneswar India

We have successfully attempted to solve the equations of full-MHD model within the framework of Ψ- ωformulation with an objective to evaluate the performance of a new higher order scheme to predict better values of control parameters of the flow. In particular for MHD flows, magnetic field and electrical conductivity are the control parameters. In this work, the results from our efficient high order accurate scheme are compared with the results of second order method and significant discrepancies are noted in separation length, drag coefficient and mean Nusselt number. The governing Navier-Stokes equation is fully nonlinear due to its coupling with Maxwell’s equations. The momentum equation has several highly nonlinear body-force terms due to full-MHD model in cylindrical polar system. Our high accuracy results predict that a relatively lower magnetic field is sufficient to achieve full suppression of boundary layer and this is a favorable result for practical applications. The present computational scheme predicts that a drag-coefficient minimum can be achieved when β=0.4 which is much lower when compared to the value β=1 as given by second order method. For a special value of β=0.65, it is found that the heat transfer rate is independent of electrical conductivity of the fluid. From the numerical values of physical quantities, we establish that the order of accuracy of the computed numerical results is fourth order accurate by using the method of divided differences.

关键词： Full-MHD Equations Forced Convective Heat Transfer High Order Compact Schemes Divided Differences

Minimizing transmission loss using inspired ant colony optimization and Markov Chain Monte Carlo in underwater WSN environment

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Journal of Ocean Engineering and Science 2019年第4期4卷 317-327页

作者： raj Priyadarshini r sivakumar N Department of Computer Science and Engineering Pondicherry Engineering CollegeEast Coast RoadPillaichavadiPuducherry 605014India

In Underwater Wireless Sensor Networks(UWSNs),the most important challenging issues are propagation delay,high error probability,high latency,high communication cost,limited bandwidth,limited memory,low packet delivery ratio,and transmission *** our proposed work,the various efforts are taken to minimize the propagation delay and transmission loss during data transmission in an underwater environment.A hybrid mechanism is implemented to improve energy efficiency for faster data transmission in underwater *** the underwater environment of acoustic channel condition,propagation delay and transmission loss lead to high complexity in accessing the information and also it is difficult to obtain the Channel Status Information(CSI).To address this problem,Ant Colony Optimization(ACO)routing with Markov Chain Monte Carlo(MCMC)algorithm is used and to capture the transmission loss in the MCMC approach,CSI Forecast Prediction(FP)algorithm is *** experimental simulations are evaluated by utilizing the performance evaluation metrics such as Transmission Loss,Probability Density Function,Average Delay and *** the simulation results it is evident that the proposed algorithm,ACO-MCMC has recorded the minimum transmission loss,increase in probability density function,minimum average delay and maximum throughput of the network when compared to the existing algorithms.

关键词： UWSN ACO-MCMC CSI Markov Chain Monte Carlo Transmission loss Probability density function

Stabilizing Energy Consumption in Unequal Clusters of Wireless Sensor Networks

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Computers, Materials & Continua 2020年第7期64卷 81-96页

作者： Nithya rekha sivakumar Department of Computer Sciences College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadh11671Saudi Arabia

In the past few decades,Energy Efficiency(EE)has been a significant challenge in Wireless Sensor Networks(WSNs).WSN requires reduced transmission delay and higher throughput with high quality services,it further pays much attention in increased energy consumption to improve the network *** collect and transmit data Clustering based routing algorithm is considered as an effective *** Head(CH)acts as an essential role in network connectivity and perform data transmission and data aggregation,where the energy consumption is superior to non-CH *** clustering approaches attempts to cluster nodes of same ***,owing to randomly distributed node distribution,a cluster with equal nodes is not an obvious possibility to reduce the energy *** resolve this issue,this paper provides a novel,Balanced-Imbalanced Cluster Algorithm(B-IBCA)with a Stabilized Boltzmann Approach(SBA)that attempts to balance the energy dissipation across uneven clusters in WSNs.B-IBCA utilizes stabilizing logic to maintain the consistency of energy consumption among sensor nodes’.So as to handle the changing topological characteristics of sensor nodes,this stability based Boltzmann estimation algorithm allocates proper radius amongst the sensor *** simulation shows that the proposed B-IBCA outperforms effectually over other approaches in terms of energy efficiency,lifetime,network stability,average residual energy and so on.

关键词： WSN stability cluster head node balancing average residual energy