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Construction of multiple new analytical soliton solutions and various dynamical behaviors to the nonlinear convection-diffusion-reaction equation with power-law nonlinearity and density-dependent diffusion via Lie symmetry approach together with a couple of integration approaches

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Journal of Ocean Engineering and Science 2023年第3期8卷 226-237页

作者： Shoukry El-Ganaini sachin kumar Monika Niwas Department of Mathematics Faculty of ScienceDamanhour UniversityDamanhour 22514Egypt Department of Mathematics Faculty of Mathematical SciencesUniversity of DelhiDelhi 110007India Department of Mathematics University of DelhiDelhi 110007India

By taking advantage of three different computational analytical methods:the Lie symmetry analysis,the generalized Riccati equation mapping approach,and the modified Kudryashov approach,we construct multiple new analytical soliton solutions to the nonlinear convection-diffusion-reaction equation(NCDR)with power-law nonlinearity and density-dependent *** symmetry analysis is one of the pow-erful techniques that reduce the higher-order partial differential equation into an ordinary differential equation by reduction of independent *** the Lie group technique,we obtain one-parameter in-variant transformations,determining equations and corresponding vectors for the considered convection-diffusion-reaction *** treating the parameters of the governing equation as constants,the ap-plied methods yield a variety of new closed-form solutions,including inverse function solutions,periodic solutions,exponential function solutions,dark solitons,singular solitons,combo bright-singular solitons,and the combine of bright-dark solitons and dark-bright ***,using the Bäcklund transfor-mation of the generalized Riccati equation and modified Kudryashov method,we can construct multiple solitons and other solutions of the considered *** obtained new solutions of this work demon-strate that the used approaches are powerful and effective in dealing with nonlinear equations,and that these solutions are required to explain many biological and physical *** our obtained solutions of this paper with the ones obtained in the literature,we see that our solutions are new and not reported *** newly formed soliton solutions will be more beneficial in the various dis-ciplines of ocean engineering,plasma physics,and nonlinear sciences.

关键词： Lie symmetry analysis Generalized riccati equation mapping Modified kudryashov approach Nonlinear convection-diffusion-reaction equation Solitary wave solutions Closed form solutions Backlund transformation Exact solution Dynamical wave structures Bäcklund transformation

A Delay-dependent Dynamic Wide Area Damping Controller for Renewable Energy Integrated Power System Resilient to Communication Failure

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CSEE Journal of Power and Energy Systems 2023年第2期9卷 577-588页

作者： Anirban Sengupta Dushmanta kumar das Bidyadhar Subudhi Department of Electrical and Electronics Engineering Sikkim Manipal Institute of TechnologySMUSIkkim737136 India Department of Electrical and Electronics Engineering National Institute of TechnologyNagalandDimapur797103 India School of Electrical Science Indian Institute of TechnologyGoaIndia

Integration of renewable energy sources(RES)with a conventional power system has a detrimental effect on interarea *** popular RESs are solar photovoltaic(PV)and wind energy conversion systems(WECS).Both solar PV power generation and WECS are integrated with power systems using a power electronic *** the amount of RES generation lead towards reduction of system damping,which leads towards inter-area ***,the intermittent behavior of a RES reduces the effectiveness of damping controllers.A dynamic controller based wide area damping controller(WADC)is proposed in this paper to increase small signal stability of a RES integrated power *** WADC is designed for contemplating delay in a communication channel,communication failure and *** anti-windup compensator is developed to overcome the effect of actuator ***,the gain of the anti-windup compensator is calculated using LyapunovKrasovskii functional(LKF)in terms of linear matrix inequality(LMI).The actuator considered in this paper is a unified power flow controller(UPFC).Efficacy of PV and wind power integration on power system is also *** efficacy of the developed dynamic controller is verified using IEEE 39 bus and 68 bus power system.

关键词： Actuator saturation communication failure linear matrix inequality renewable energy sources time delay wide area damping control

Specific wave profiles and closed-form soliton solutions for generalized nonlinear wave equation in(3+1)-dimensions with gas bubbles in hydrodynamics and fluids

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Journal of Ocean Engineering and Science 2023年第1期8卷 91-102页

作者： sachin kumar Ihsanullah Hamid M.A.Abdou Department of Mathematics Faculty of Mathematical SciencesUniversity of DelhiDelhi 110007India Department of Mathematics College of SciencesUniversity of BishaP.O.Box 344Bisha 61922Saudi Arabia Physics Department Faculty of ScienceMansoura UniversityMansoura 35516Egypt

Nonlinear evolution equations(NLEEs)are frequently employed to determine the fundamental principles of natural *** equations are studied extensively in nonlinear sciences,ocean physics,fluid dynamics,plasma physics,scientific applications,and marine *** generalized exponen-tial rational function(GERF)technique is used in this article to seek several closed-form wave solutions and the evolving dynamics of different wave profiles to the generalized nonlinear wave equation in(3+1)dimensions,which explains several more nonlinear phenomena in liquids,including gas bubbles.A large number of closed-form wave solutions are generated,including trigonometric function solutions,hyper-bolic trigonometric function solutions,and exponential rational functional *** the dynamics of distinct solitary waves,a variety of soliton solutions are obtained,including single soliton,multi-wave structure soliton,kink-type soliton,combo singular soliton,and singularity-form wave *** de-termined solutions have never previously been *** dynamical wave structures of some analyt-ical solutions are graphically demonstrated using three-dimensional graphics by providing suitable values to free *** technique can also be used to obtain the soliton solutions of other well-known equations in engineering physics,fluid dynamics,and other fields of nonlinear sciences.

关键词： Closed-form solutions Dynamical wave patterns Analytic solutions Nonlinear wave equation GERF Method Solitary waves Solitons

Off-Pump Coronary Artery Bypass Grafting in Patients with Left Ventricular Dysfunction: Short-Term Results from a Single Center in Bangladesh

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World Journal of Cardiovascular Surgery 2024年第9期14卷 145-156页

作者： Muhit Abdullah Md. Abir Tazim Chowdhury Satyajit Sharma Rehana Akther Munama Magdum Munjerin Refat Synthee Md. Zafar-Al-Nimari Saikat das Gupta Saleh Ahmed Samir kumar Biswas M. Quamrul Islam Talukder Farooque Ahmed Department of Cardiac Surgery National Heart Foundation Hospital and Research Institute (NHFH&RI) Dhaka Bangladesh Department of Cardiothoracic and Vascular Surgery Evercare Hospital Dhaka Dhaka Bangladesh Ispahani Islamia Eye Institute & Hospital Khamarbari Dhaka Bangladesh National Institute of Preventive and Social Medicine Dhaka Bangladesh Square Hospital Dhaka Bangladesh

Background: Off-pump coronary artery bypass grafting (OPCAB) is considered a safer alternative to on-pump surgery, especially in patients with left ventricular dysfunction (LVD). Objectives: This study assessed short-term outcomes and functional improvements in LVD patients post-OPCAB. Methods: The study included 200 coronary artery disease patients who underwent isolated off-pump coronary artery bypass grafting (OPCAB) at the National Heart Foundation Hospital and Research Institute between January 2019 and June 2020. Patients were categorized into Group 1, with a left ventricular ejection fraction (LVEF) of 30% - 39%, and Group 2, with an LVEF of 40% or higher. Echocardiographic assessments of left ventricular dimensions and ejection fraction were performed preoperatively, at discharge, and one month postoperatively. Results: In Group 1, preoperative left ventricular internal dimensions during diastole (LVIDd) and systole (LVIDs) were 53.48 ± 4.40 mm and 44.23 ± 3.93 mm, respectively, with a left ventricular ejection fraction (LVEF) of 35.28% ± 2.26%. At discharge, these values improved to 51.58 ± 4.04 mm (LVIDd), 41.23 ± 5.30 mm (LVIDs), and 39.25% ± 3.75% (LVEF). One month postoperatively, further improvements were observed: 46.29 ± 3.76 mm (LVIDd), 37.45 ± 3.68 mm (LVIDs), and 43.22% ± 4.67% (LVEF). Group 2 showed similar positive outcomes, with preoperative values of 47.09 ± 5.06 mm (LVIDd), 35.11 ± 5.25 mm (LVIDs), and 50.13% ± 7.25% (LVEF), improving to 42.37 ± 4.18 mm (LVIDd), 31.05 ± 4.19 mm (LVIDs), and 55.33% ± 7.05% (LVEF) at one month postoperatively. Both groups demonstrated significant improvements in left ventricular function and NYHA class, with most patients moving from class III/IV to I/II. Complications were minimal, and no mortality was observed. Conclusion: OPCAB is safe and effective for patients with LVEF 30% - 39% and LVEF ≥ 40%, providing significant short-term functional improvements without increased risk.

关键词： Off-Pump Coronary Artery Bypass Grafting Left Ventricular Dysfunction (LVD) Short-Term Outcomes

A Parallel Approach to Discords Discovery in Massive Time Series Data

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Computers, Materials & Continua 2021年第2期66卷 1867-1878页

作者： Mikhail Zymbler Alexander Grents Yana Kraeva sachin kumar Department of Computer Science South Ural State UniversityChelyabinsk454080Russian

A discord is a refinement of the concept of an anomalous subsequence of a time *** one of the topical issues of time series mining,discords discovery is applied in a wide range of real-world areas(medicine,astronomy,economics,climate modeling,predictive maintenance,energy consumption,etc.).In this article,we propose a novel parallel algorithm for discords discovery on high-performance cluster with nodes based on many-core accelerators in the case when time series cannot fit in the main *** assumed that the time series is partitioned across the cluster nodes and achieved parallelization among the cluster nodes as well as within a single *** a cluster node,the algorithm employs a set of matrix data structures to store and index the subsequences of a time series,and to provide an efficient vectorization of computations on the *** each node,the algorithm processes its own partition and performs in two phases,namely candidate selection and discord refinement,with each phase requiring one linear scan through the *** the local discords found are combined into the global candidate set and transmitted to each cluster ***,a node performs refinement of the global candidate set over its own partition resulting in the local true discord ***,the global true discords set is constructed as intersection of the local true discord *** experimental evaluation on the real computer cluster with real and synthetic time series shows a high scalability of the proposed algorithm.

关键词： Time series discords discovery computer cluster many-core accelerator vectorization

Litterfall,decomposition and nutrient release of Shorea robusta and Tectona grandis in a sub-tropical forest of West Bengal,Eastern India

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Journal of Forestry Research 2016年第5期27卷 1055-1065页

作者： Chittaranjan das Naba kumar Mondal Department of Environmental Science The University of Burdwan

We studied leaf litter fall, decomposition and nutrient release patterns of Shorea robusta and Tectona grandis by using a litter bag technique to better understand the release pattern of nutrients to soil from leaf litter. Annual litterfall varied from 13.40 ± 2.56 t ha-1 a-1 for S. robusta to 11.03 ± 3.72 t ha-1 a-1 for T. grandis and the decay constant （k） of decomposed leaf litter was distinctly higher for T. grandis （2.70 ± 0.50 a-1） compared to S. robusta （2.41 ±0.30 a-1）. Biomass loss was positively correlated with the initial litter C, WSC, C/N and ash content in S. robusta and N, P and K concentration for T. grandis. Biomass was negatively correlated with lignin and L/N ratio for S. robusta and L, WSC, L/N and C/N ratio for T. grandis （P 〈 0.01）. Nutrient use efficiency （NUE） and nutrient accumulation index （NAI） of S. robusta was higher than for T. grandis. The retranslocation of bioelements from senescent leaves ranked as P 〉 N 〉 K. Annual N, P and K input to soil through litterfall differed significantly between the two species in the following order： N〉K^P. S. robusta was superior in terms of K and P return and T. grandis was superior in terms of N return. The two tree species showed a similar patterns of nutrient release （K 〉 P 〉 N） during decomposition of their leaf *** of N, K and P were the primary limiting nutrients returned to soil through litterfall with important roles in soil fertility and forest productivity.

关键词： Decay constant Lignin Litterfall Nutrientreturn Decomposition Nutrient use efficiency

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

A malaria model with Caputo-Fabrizio and Atangana-Baleanu derivatives

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International Journal of Modeling, Simulation, and Scientific Computing 2021年第2期12卷 138-164页

作者： Hamadjam Abboubakar Pushpendra kumar Norodin A.Rangaig sachin kumar Department of Computer Engineering University Institute of Technology University of Ngaound´er´e P.O.Box 455 Ngaound´er´eCameroon Department of Mathematics and Statistics School of Basic and Applied Sciences Central University of Punjab BathindaPunjab-151001India Department of Physics Mindanao State University-Main Campus Marawi City 9700Philippines

In this paper,we study two fractional models in the Caputo–Fabrizio sense and Atangana–Baleanu sense,in which the effects of malaria infection on mosquito biting behavior and attractiveness of humans are *** Lyapunov theory,we prove the global asymptotic stability of the unique endemic equilibrium of the integer-order model,and the fractional models,whenever the basic reproduction number R0 is greater than *** using fixed point theory,we prove existence,and conditions of the uniqueness of solutions,as well as the stability and convergence of numerical *** simulations for both models,using fractional Euler method and Adams–Bashforth method,respectively,are provided to confirm the effectiveness of used approximation methods for different values of the fractional-orderγ.

关键词： Malaria fractional models Caputo-Fabrizio derivative Atangana-Baleanu derivative in the Caputo sense asymptotic stability fractional Euler method Adams-Bashforth method

Abundant different types of exact soliton solution to the (4+1)-dimensional Fokas and (2+1)-dimensional breaking soliton equations

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Communications in Theoretical Physics 2021年第10期73卷 64-80页

作者： sachin kumar Monika Niwas M S Osman M A Abdou Department of Mathematics Faculty of Mathematical SciencesUniversity of DelhiDelhi-110007India Department of Mathematics Faculty of ScienceCairo UniversityGiza 12613Egypt Department of Mathematics Faculty of Applied ScienceUmm Alqura UniversityMakkah 21955Saudi Arabia Department of Physics College of SciencesUniversity of BishaP.O.Box 344Bisha 61922Saudi Arabia Department of Physics Faculty of ScienceMansoura University35516 MansouraEgypt

The prime objective of this paper is to explore the new exact soliton solutions to the higher-dimensional nonlinear Fokas equation and(2+1)-dimensional breaking soliton equations via a generalized exponential rational function(GERF) method. Many different kinds of exact soliton solution are obtained, all of which are completely novel and have never been reported in the literature before. The dynamical behaviors of some obtained exact soliton solutions are also demonstrated by a choice of appropriate values of the free constants that aid in understanding the nonlinear complex phenomena of such equations. These exact soliton solutions are observed in the shapes of different dynamical structures of localized solitary wave solutions, singular-form solitons, single solitons,double solitons, triple solitons, bell-shaped solitons, combo singular solitons, breather-type solitons,elastic interactions between triple solitons and kink waves, and elastic interactions between diverse solitons and kink waves. Because of the reduction in symbolic computation work and the additional constructed closed-form solutions, it is observed that the suggested technique is effective, robust, and straightforward. Moreover, several other types of higher-dimensional nonlinear evolution equation can be solved using the powerful GERF technique.

关键词： nonlinear evolution equations soliton solutions exact solutions generalized exponential rational function method solitary waves