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Effects of Nonmonotonic Functional Responses on a Disease Transmission Model:Modeling and Simulation

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Communications in Mathematics and Statistics 2022年第2期10卷 195-214页

作者： abhishek Kumar Nilam Department of Applied Mathematics Delhi Technological UniversityDelhi 110042India

In this article,a novel susceptible-infected-recovered epidemic model with nonmonotonic incidence and treatment rates is proposed and analyzed *** Monod-Haldane functional response is considered for nonmonotonic behavior of both incidence rate and treatment *** model analysis shows that the model has two equilibria which are named as disease-free equilibrium(DFE)and endemic equilibrium(EE).The stability analysis has been performed for the local and global behavior of the DFE and *** the help of the basic reproduction number(R_(0)),we investigate that DFE is locally asymptotically stable when R_(0)*** local stability of DFE at R_(0)=1 has been analyzed,and it is obtained that DFE exhibits a forward transcritical ***,we identify conditions for the existence of EE and show the local stability of EE under certain ***,the global stability behavior of DFE and EE has been ***,numerical simulations have been done in the support of our theoretical findings.

关键词： Monod-Haldane functional Basic reproduction number Local and global stability Bifurcation

Deep Neural Network and Pseudo Relevance Feedback Based Query Expansion

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Computers, Materials & Continua 2022年第5期71卷 3557-3570页

作者： abhishek Kumar Shukla Sujoy Das Department of Mathematics Bio-Informatics and Computer ApplicationsMaulana Azad National Institute of Technology BhopalBhopalMadhya Pradesh462003India

The neural network has attracted researchers immensely in the last couple of years due to its wide applications in various areas such as Data mining,Natural language processing,Image processing,and Information retrieval *** embedding has been applied by many researchers for Information retrieval *** this paper word embedding-based skip-gram model has been developed for the query expansion *** terms are obtained from the top“k”initially retrieved documents using the Pseudo relevance feedback model and then they are trained using the skip-gram model to find the expansion terms for the user *** performance of the model based on mean average precision is *** proposed model compares with other existing *** improvement of 6.61%,6.93%,and 9.07%on MAP value is observed compare to the Original query,BM25 model,and query expansion with the Chi-Square model *** proposed model also retrieves 84,25,and 81 additional relevant documents compare to the original query,query expansion with Chi-Square model,and BM25 model respectively and thus improves the recall value *** per query analysis reveals that the proposed model performs well in 30,36,and 30 queries compare to the original query,query expansion with Chi-square model,and BM25 model respectively.

关键词： Information retrieval query expansion word embedding neural network deep neural network

Three-phase AC-DC Converter for Direct-drive PMSG-based Wind Energy Conversion System

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Journal of Modern Power Systems and Clean Energy 2023年第2期11卷 589-598页

作者： Kumar abhishek Singh Ayushi Chaudhary Kalpana Chaudhary Department of Electrical Engineering Indian Institute TechnologyVaranasiIndia Department of Electrical Engineering Indian Institute TechnologyKanpurIndia

In this paper,a wind energy conversion system(WECS)is presented for the electrification of rural areas with wind energy availability.A three-phase AC-DC converter based on a bridgeless Cuk converter is used for power extraction from the permanent magnet synchronous generator(PMSG).The bridgeless topology enables the elimination of the front-end diode bridge rectifier(DBR).Moreover,the converter has fewer components,simple control,and high efficiency,making it suitable for a small-scale WECS.A squirrel cage induction motor(SCIM)is used to emulate a MOD-2 wind turbine to implement the PMSG-based WECS.A direct-drive eight-pole PMSG is used in this study;thus,a low-input-voltage system is *** converter is designed to operate in the discontinuous inductor current mode(DICM)for inherent power factor correction(PFC)and the maximum power point tracking(MPPT)is achieved through the tip-speed ratio(TSR)*** performance of the developed system is analyzed through simulation,and a 500 W hardware prototype is developed and tested in different wind speed conditions.

关键词： Permanent magnet synchronous generator(PMSG) three-phase AC-DC converter wind energy conversion system(WECS) wind turbine emulator

Implications of REE incorporation and host sediment influence on the origin and growth processes of ferromanganese nodules from Central Indian Ocean Basin

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Geoscience Frontiers 2021年第3期12卷 609-623页

作者： Simontini Sensarma abhishek Saha Arghya Hazra CSIR-National Institute of Oceanography Dona PaulaGoa 403004India Indian Institute of Science BangaloreKarnataka 560012India School of Earth Ocean and Atmospheric SciencesGoa UniversityGoa 403206India

This study presents new major,trace and REE data for thirty-five ferromanganese nodules recovered from areas representing three different sediment types(siliceous,red clay and their transition zone)in the Central Indian Ocean Basin(CIOB)to address their genetic aspects,classification,growth rate,nature of host sediments and influence of REE in the processes of nodule *** nodules from CIOB are mostly either hydrogenetic(metals coming from oxygenated bottom water)and diagenetic(metals coming from suboxic sediment pore water)or a combination of both,depending on the source of supply of ***,a number of biogeochemical processes mediate this supply of metals which again changes from time to time,making the nodule growth process highly *** study suggests that at the initial stage of nodule growth,host sediments do not play much role in controlling the growth processes for which REEs can enter both Mn and Fe oxyhydroxide phases ***,the bottom water signature is imprinted in these early formed nodules irrespective of their host sediment substrate but with gradual growth and burial in the sediment,the main mode of metal enrichment becomes diagenetic through sediment pore *** tends to increase the concentration of Mn,Ni and Cu over other elements which are retained in the sediment *** the REEs,Ce concentration of the nodules shows significant positive anomaly due to variation in redox potential and hence its magnitude can be used to get an idea about the metal enrichment procedure and the genetic type of the ***,based on host sediment only,not much difference is found in the magnitude of Ce anomaly in these *** the other hand,discrimination diagram,based on HFSE and REY chemistry,indicates that most of these nodules are of diagenetic origin under oxic condition with a trend towards hydrogenetic ***,the genetic type of the ferromanganese nodules from the CIOB are more effectively differentiated

关键词： Central Indian Ocean Basin Ferromanganese nodules Deep-sea sediments Rare earth elements Geochemical discrimination

Vasectomy reversal： a clinical update

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Asian Journal of Andrology 2016年第3期18卷 365-371,I0007页

作者： abhishek P Patel Ryan P Smith Department of Urology University of Virginia Charlottesville VA 22908-0422 USA.

Vasectomy is a safe and effective method of contraception used by 42-60 million men worldwide. Approximately 3%-6% of men opt for a vasectomy reversal due to the death of a child or divorce and remarriage, change in financial situation, desire for more children within the same marriage, or to alleviate the dreaded postvasectomy pain syndrome. Unlike vasectomy, vasectomy reversal is a much more technically challenging procedure that is performed only by a minority of urologists and places a larger financial strain on the patient since it is usually not covered by insurance. Interest in this procedure has increased since the operating microscope became available in the 1970s, which consequently led to improved patency and pregnancy rates following the procedure. In this clinical update, we discuss patient evaluation, variables that may influence reversal success rates, factors to consider in choosing to perform vasovasostomy versus vasoepididymostomy, and the usefulness of vasectomy reversal to alleviate postvasectomy pain syndrome. We also review the use of robotics for vasectomy reversal and other novel techniques and instrumentation that have emerged in recent years to aid in the success of this surgery.

关键词： epididymovasostomy microsurgery postvasectomy orchialgia postvasectomy pain syndrome vas deferens vasectomy vasectomy reversal vasoepididymostomy vasovasostomy

Large eddy simulations of a turbulent mixing layer periodically excited with fundamental and third harmonic frequency

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Chinese Journal of Aeronautics 2023年第5期36卷 33-40页

作者： Jörg SCHLÜTER Dan ZHAO abhishek SARKAR School of Engineering Deakin UniversityWaurn Ponds 3216Australia College of Engineering University of CanterburyChristchurch 8041New Zealand School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore

A better understanding of the mixing behavior of excited turbulent mixing layers is critical to a number of aerospace *** studies of excited turbulent mixing layers focused on single frequency excitation or the excitation with fundamental and its second harmonic *** is a lack of detailed studies on applying low and higher frequency *** this study,we have performed large-eddy simulations of periodically excited turbulent mixing *** excitation consists of a fundamental frequency and its third *** have used phase-averaging to identify the vortex structure and strength in the mixing layer,and we have studied the vortex *** different vortex paring mechanisms are observed depending on the phase shift between the two excitation *** influence of these two mechanisms on the mixing of a passive scalar is also *** is found that exciting the mixing layer with these low and high frequencies has initially an adverse influence on the mixing process;however,it improves the mixing further downstream of the splitter plate with the excitation using a phase shift ofΔφ=πshowing the best mixing *** present works shed lights on the fundamental vortex dynamics,and has great potential for aeronautical,automotive and combustion engineering applications.

关键词： Flow control Flow excitation Large eddy simulations Turbulent mixing layer Vortex dynamics

Advances in endobariatrics:past,present,and future

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Gastroenterology Report 2023年第1期11卷 140-150页

作者： abhishek Shenoy Allison R.Schulman Division of Gastroenterology and Hepatology University of MichiganMichigan MedicineAnn ArborMIUSA Department of Surgery University of MichiganMichigan MedicineAnn ArborMIUSA

The obesity epidemic in the USA and worldwide is well documented and continues to *** metabolic and bariatric therapies may offer a less invasive approach than surgical *** article will review advances in endobariatrics over the last several decades,addressing the past and current state of bariatric and metabolic *** and Drug Administration-cleared devices and interventions currently under investigation are described including gastric devices,gastric remodeling procedures,small-bowel devices,duodenal ablation,as well as procedures to address weight regain after bariatric *** studies evaluating gastric and duodenal combination therapy,adjunctive pharmacotherapy,as well as individualized precision-health algorithms are underway.

关键词： metabolic devices endoscopic sleeve gastroplasty obesity endobariatrics bariatric therapy

Preparation,crystallization,microstructure and dielectric properties of lead bismuth titanate borosilicate glass ceramics

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Journal of Advanced Ceramics 2014年第3期3卷 194-206页

作者： Chandkiram RGAUTAM abhishek MADHESHIYA Ranabrata MAZUMDER Advanced Glass and Glass Ceramic Research Laboratory Department of PhysicsUniversity of LucknowLucknow 226007India Department of Ceramic Engineering National Institute of TechnologyRouerkela 769008India

Various bulk and transparent glasses were prepared by rapid melt quenching technique in the glass system 55[(Pb_(x)Bi_(1-x))TiO_(3)]-44[2Si_(O)2B_(2)O_(3)]-La2O3(x=0-0.7).The X-ray diffraction(XRD)studies of the glass samples confirmed the amorphous *** differential thermal analyses(DTA)were carried out from room temperature to 900℃with a heating rate of 10℃/*** DTA patterns of the samples showed one or more exothermic sharp peaks shifting towards lower temperature side with increasing concentration of bismuth oxide(BiO).On the basis of DTA results,the solid solution of bismuth titanum oxide(Bi_(2)Ti_(2)O_(7))/lead bismuth titanium oxide(Pb3Bi4Ti6O21)was precipitated in borosilicate glassy matrix as a major *** glasses were subjected to 4 h and 8 h heat treatment schedules to convert into glass *** analysis of these glass ceramic samples showed that the major crystalline phase of the entire glass ceramic samples with 0≤x≤0.5 is found to have cubic crystal structure,while it is tetragonal for glass ceramic sample with x=*** scanning electron microscopy(SEM)micrographs indicated the uniform distribution of Bi_(2)Ti_(2)O_(7)and Pb3Bi4Ti6O21 crystallites in the glassy matrix.

关键词： lead bismuth titanate differential thermal analysis(DTA) crystallization scanning electron microscopy(SEM) dielectric behavior

Effects of defects on the electronic properties of WTe_2 armchair nanoribbons

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Journal of Semiconductors 2014年第11期35卷 10-15页

作者： Bahniman Ghosh abhishek Gupta Bhupesh Bishnoi Microelectronics Research Center 10100Burnet RoadBldg.160University of Texas at AustinAustinTX78758USA Department of Electrical Engineering Indian Institute of Technology Kanpur

We have investigated the electronic properties of WTe2 armchair nanoribbons with defects. WTe2 nanoribbons can be categorized depending on the edge structure in two types： armchair and zigzag. WTe2 in its bulk form has an indirect band gap but nanoribbons and nanosheets of WTe2 have direct band gaps. Interestingly, the zigzag nanoribbon is metallic while the armchair nanoribbons are semiconducting. Thus they can find applications in device fabrication. Therefore, it is very important to study the effect of defects on the electronic properties of the armchair nanoribbons as these defects can impair the device properties and characteristics. We have considered defects such as： vacancy, rough edge, wrap, ripple and twist in this work. We report the band gap variation with these defects. We have also studied the change in band gap and total energy with varying degrees of wrap, ripple and twist.

关键词： electronic property WTe2 armchair nanoribbons defects