检索结果-南通市图书馆

Kadomstev-Petviashvilli-Burgers (KPB) Equation in a Five Component Cometary Plasma with Kappa Described Electrons and Ions

在线全文

学校读者我要写书评

暂无评论

Journal of Applied Mathematics and Physics 2015年第11期3卷 1431-1442页

作者： Manesh Michael Sreekala Gopinathan Sijo Sebastian Neethu T. Willington Anu Varghese Renuka Gangadharan chandu venugopal School of Pure & Applied Physics Mahatma Gandhi University Priyadarshini Hills Kottayam Kerala India Department of Physics C. M. S. College Kottayam India Kerala State Council for Science Technology & Environment Sasthra Bhavan Pattom Thiruvananthapuram India

We investigate the existence of Ion-Acoustic solitary/shock waves in a five component cometary plasma consisting of positively and negatively charged oxygen ions, kappa described hydrogen ions, hot electrons and cold electrons. The KPB equation is derived for the system;its solution is plotted for different kappa values, as well as for the temperature ratios of ions. It is found that the amplitude of solitary structure increases with increasing kappa values and negatively charged oxygen ion densities. As the temperature of the positively charged oxygen ions increases, the amplitude of solitary wave also increases. We have also studied the dependence of coefficients of the KPB equation on physical parameters relevant to comet Halley.

关键词： Cometary Multi-Ion Plasma Ion-Acoustic Solitary Wave Shock Wave KPB Equation

Performance analysis of jig for coal cleaning using 3D response surface methodology

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

International Journal of Mining Science and Technology 2017年第2期27卷 333-337页

作者： Kumar Shravan venugopal R. Department of Fuel and Mineral Engineering Indian Institute of Technology(ISM)Dhanbad826004India

Beneficiation of coal of -4.76 mm + 3 mm size fraction was investigated in a laboratory model Denver *** variables were studied to analyze their effect on the performance of jig in terms of yield and ash content of clean coal. Three-factor three-level Box-Behnken design of experiments with response surface methodology(RSM) was employed to understand the performance behavior of jig. From the study, the bed height was found to be the most significant parameter affecting the yield and ash content of clean coal. It was possible to reduce the ash content from 24.32% in feed to an ash content of 16.55% in clean coal at 2 L/min water flow rate and 10 min jigging time. Influence of operating variables of the jig on responses was presented and discussed in 3D surface plots. The developed model was found to be significant within the range of parameters under investigation with correlation of co-efficient values as 0.99(yield) and 0.98(ash).

关键词： Coal beneficiation Jigging Bed height 3D-RSM Box-Behnken

Blockchain: Secured Solution for Signature Transfer in Distributed Intrusion Detection System

在线全文

学校读者我要写书评

暂无评论

Computer Systems Science & Engineering 2022年第1期40卷 37-51页

作者： Shraddha R.Khonde venugopal Ulagamuthalvi Department of Computer Science and Engineering Sathyabama Institute of Science and TechnologyChennai600119India Department of Computer Engineering M.E.S.College of EngineeringS.P.Pune UniversityPune411001India

Exchange of data in networks necessitates provision of security and *** networks compromised by intruders are those where the exchange of data is at high *** main objective of this paper is to present a solution for secure exchange of attack signatures between the nodes of a distributed *** activities are monitored and detected by the Intrusion Detection System(IDS)that operates with nodes connected to a distributed *** IDS operates in two phases,where the first phase consists of detection of anomaly attacks using an ensemble of classifiers such as Random forest,Convolutional neural network,and XGBoost along with genetic algorithm to improve the performance of *** novel attacks detected in this phase are converted into signatures and exchanged further through the network using the blockchain framework in the second *** phase uses the cryptosystem as part of the blockchain to store data and secure it at a higher *** blockchain is implemented using the Hyperledger Fabric v1.0 and v2.0,to create a prototype for secure signature *** exchanges signatures in a much more secured manner using the blockchain architecture when implemented with version 2.0 of Hyperl-edger *** performance of the proposed blockchain system is evaluated on UNSW NB15 *** performance has been evaluated in terms of execution time,average latency,throughput and transaction processing *** evidence of the proposed IDS system demonstrates improved performance with accuracy,detection rate and false alarm rate(FAR)as key parameters *** and detection rate increase by 2%and 3%respectively whereas FAR reduces by 1.7%.

关键词： Blockchain intrusion detection system machine learning algorithms secured communication ensemble approach

Microstructural Characterization and Mechanical Properties of Powder Metallurgy Dual Phase Steel Preforms

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

Journal of Materials Science & Technology 2012年第12期28卷 1085-1094页

作者： K. Mahesh S. Sankaran P. venugopal Department of Metallurgical and Materials Engineering IIT Madras Chennai India

In order to improve the mechanical properties of powder metallurgy （P/M） ferrite-pearlite steel, a dual phase （DP） ferrite-martensite steel was produced through intercritical annealing of sintered P/M preforms. Mi-crostructures of the sintered and DP steels were examined with optical, scanning and transmission electron microscopes. Mechanical properties were evaluated through hardness measurements and compression tests. Microstructural studies revealed that sintered steel contained polygonal ferrite-pearlite while the DP steel contained polygonal, lath and acicular ferrite along with lath-type martensite as microstructural constituents. In DP steels, with increasing mean preform density, the microstructure contained fine and continuous network of martensite colonies with minimum porosity. The work hardening rate vs plastic strain plots （Jaoul-Crussard analysis） of both the steels revealed typical three stage deformation behaviour for low and high mean preform densities. Compression tests revealed that, DP P/M steel displayed higher strength-plasticity combination than the sintered steel.

关键词： Powder metallurgy Dual phase Jaoul-Crussard analysis Work hardening rate

BHLM:Bayesian theory-based hybrid learning model for multi-document summarization

在线全文

学校读者我要写书评

暂无评论

International Journal of Modeling, Simulation, and Scientific Computing 2018年第2期9卷 229-250页

作者： S.Suneetha A.venugopal Reddy Computer Science and Engineering Department Hasvita Institute of Engineering and Technology Hyderabad India Jawaharlal Nehru Technological University Hyderabad India

In order to understand and organize the document in an efficient way,the multidocument summarization becomes the prominent technique in the Internet *** the information available is in a large amount,it is necessary to summarize the document for obtaining the condensed *** perform the multi-document summarization,a new Bayesian theory-based Hybrid Learning Model(BHLM)is proposed in this ***,the input documents are preprocessed,where the stop words are removed from the ***,the feature of the sentence is extracted to determine the sentence score for summarizing the *** extracted feature is then fed into the hybrid learning model for ***,learning feature,training error and correlation coefficient are integrated with the Bayesian model to develop ***,the proposed method is used to assign the class label assisted by the mean,variance and probability ***,based on the class label,the sentences are sorted out to generate the final summary of the *** experimental results are validated in MATLAB,and the performance is analyzed using the metrics,precision,recall,F-measure and *** proposed model attains 99.6%precision and 75%rouge-1 measure,which shows that the model can provide the final summary efficiently.

关键词： Multi-document text feature sentence score hybrid learning model Bayesian theory

Influence of Rotational Speed on Microstructure and Mechanical Properties of Dissimilar Metal AISI 304-AISI 4140 Continuous Drive Friction 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

Journal of Iron and Steel Research International 2012年第10期19卷 64-73页

作者： G Subhash Chander G Madhusudhan Reddy A venugopal Rao Swarna Bharathi Institute of Science and Technology Khammam 507002APIndia Defense Metallurgical Research Laboratory Kanchanbagh 500058APIndia

Fundamental investigation of continuous drive friction welding of austenitic stainless steel (AISI 304) and low alloy steel (AISI 4140) is described. The emphasis is made on the influence of rotational speed on the microstructure and mechanical properties such as hardness, tensile strength, notch tensile strength and impact toughness of the dissimilar joints. Hardness profiles across the weld show the interface is harder than the respective parent metals. In general, maximum peak hardness is observed on the stainless steel side, while other peak hardness is on the low alloy steel side. A trough in hardness distribution in between the peaks is located on the low alloy steel side. Peak hardness on the stainless steel and low alloy steel side close to the interface increases with a decrease in rotational speed. All transverse tensile joints fractured on stainless steel side near the interface. Notch tensile strength and impact toughness increase with increase in rotational speed up to 1 500 r/min and decrease thereafter. The mechanism of influence of rotational speed for the observed trends is discussed in the torque, displacement characteristics, heat generation, microstructure, fractography and mechanical properties.

关键词： friction welding dissimilar metal joint austenitic stainless steel low alloy steel microstructure impact toughness tensile strength

Impact of mangrove vegetation on seasonal carbon burial and other sediment characteristics in the Vellar-Coleroon estuary, India

在线全文

学校读者我要写书评

暂无评论

Journal of Forestry Research 2014年第4期25卷 787-794页

作者： Kandasamy Kathiresan venugopal Gomathi Raj Anburaj Kandasamy Saravanakumar Centre of Advanced Study in Marine Biology Faculty of Marine Sciences Annamalai University Parangipettai 608 502 India

This work quantified the total carbon and 12 other sediment characteristics at 10 soil depths, in planted and or natural mangrove forests in comparison with non-vegetated soil for four seasons of the year 2009-2010 in the Vellar-Coleroon estuarine complex, India. The sedi- ment characteristics varied significantly between mangrove-vegetated and non-vegetated habitats or seasons of analysis, but not between soil depths. The mangrove sediments were rich in total carbon and total or- ganic carbon as compared to non-mangrove sediments （p 〈0.01）. Total carbon was 98.2% higher in mature mangroves and 41.8% in planted mangroves than that in non-mangrove soil. Total organic carbon was as much as 2.5 times greater in mature mangroves and 2 times greater in planted mangroves than that in unvegetated soil. Carbon contents also varied many fold by season. Total carbon content was 8.6 times greater during pre-monsoon, 4.1 times greater during post-monsoon and 2.5 times greater during monsoon than during summer （P〈0.01 in all cases）. Similarly, total organic carbon was 5.9 times greater during pre-monsoon, 3.1 times greater during post-monsoon and 69% greater during monsoon than during summer. In general, higher levels of sediment carbon were recorded during pre and post-monsoon seasons than during other seasons. Total carbon concentration was correlated negatively to temperature, sand and phosphorus （P 〈0.01）; positively correlated with redox potential, silt, clay, C/N ratio, potassium （P 〈0.01） and nitrogen （P〈0.05）; but not correlated with soil depth, pH or salinity. This work revealed that the carbon burial was rapid at the annual rate of 2.8% for total carbon, and 6.7% for total organic carbon in mangrove-planted sediment. Cleating of mangroves can result in significantly and rapidly reduced carbon *** study highlights the importance of natural and plantation mangrove stands for conserving sediment carbon in the tropical coastal domain.

关键词： mangrove sediment carbon burial total carbon total organiccarbon

Non-spherical aluminum nanoparticles fabricated using picosecond laser ablation

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2020年第7期27卷 980-986页

作者： A.Brahma Swamulu S.venugopal Rao G.Krishna Podagatlapalli Department of Physics Rajiv Gandhi University of Knowledge TechnologiesNuzvidAndhra Pradesh 521202India Advanced Centre of Research in High Energy Materials(ACRHEM) University of HyderabadHyderabad 500046TelanganaIndia Department of Electronics&Physics Gandhi Institute of Technology and Management Institute of ScienceGandhi Institute of Technology and Management deemed to be UniversityVisakhapatnam 530045Andhra PradeshIndia

We report the picosecond laser ablation of aluminum targets immersed in a polar organic liquid(chloroform,CHCl3)with^2 ps laser pulses at an input energy of^350μ*** synthesized aluminum nanoparticles exhibited a surface plasmon resonance peak at^340 *** electron microscopy images of Al nanoparticles demonstrated the spherical morphology with an average size of(27±3.6)*** formation of smaller spherical Al nanoparticles and the diminished growth could be from the formation of electric double layers on the Al *** addition to spherical aluminum nanoparticles,triangular/pentagonal/hexagonal nanoparticles were also observed in the colloidal *** emission scanning electron microscopy images of ablated Al targets demonstrated laser induced periodic surface structures(LIPSSs),which were the high spatial frequency LIPSSs(HSF-LIPSSs)since their grating period was^280 ***,coarse structures with a period of^700 nm were observed.

关键词： ablation picosecond silver polar periodic surfaces electric double layers

Relationship between age, size, fecundity and climatic factors in Panax wangianus an endangered medicinal plant in the sacred grove forest of North-East India

在线全文

学校读者我要写书评

暂无评论

Journal of Forestry Research 2011年第3期22卷 427-435页

作者： N. venugopal Preeti Ahuja Plant Anatomy Lab Department of Botany North-Eastern Hill University Shillong-793022 Meghalaya India

Panax wangianus （Syn. Panax pseudoginseng） S. C. Sun （Araliaceae） is a critically endangered, medicinal plant of North-East India. The objective of this study was to determine how plant size affects flowering phenology and to evaluate the effect of climatic factors on flowering, fruiting and seed production. Data on vegetative and repro- ductive characters were monitored from 2016 individuals of Panax wangianus population in Law Lyngdoh, Smit sacred grove in Nongkrem, Shillong, India. Leaflet area was measured by a planimeter. Size variables of both vegetative and reproductive traits in different age classes were measured. Climatic factors were recorded from 2007 to 2009. Age was recorded by counting the number of bud scale scars on the rhizome. Light intensity and relative humidity were measured using a photometer, LiCor Model LI-189 and thermohygrometer respectively. Different climatic variables are correlated with vegetative and reproductive phenological events. Statistical analysis revealed that a strong positive correlation was observed between the age versus vegetative and reproductive characters, except 1%–2% plants showed neoteny. Morphological variations were observed in natural conditions on the basis of the number of prong and carpellate conditions. Phenological status revealed that most of the individuals of the age class 35–50 years and above 50 years contributed the most to flowering, fruiting and seed production. Age class was significant to predict the size of the plant and its reproductive capacity. Climatic factors such as temperature, precipitation and relative humidity show synergistic effect on both the vegetative and reproductive phases in Panax wangianus in the undisturbed Nongkrem sacred grove. The color of flowers of P. wangianus also varied depending upon the sunlight intensity. Therefore, in the view of conservationand management, the age class of 35–50 years and above 50 years is the most important for population sustainability.

关键词： Panax wangianus medicinal plant North-East India Nongkrem sacred grove climatic factors vegetative and reproductive relationship with age