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Modeling and optimal control of COVID-19 with comorbidity and three-dose vaccination in Indonesia

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Journal of Biosafety and Biosecurity 2024年第3期6卷 181-195页

作者： Muhammad Abdurrahman Rois Fatmawati Cicik Alfiniyah Santi Martini Dipo Aldila Farai Nyabadza department of mathematics Faculty of Science and TechnologyUniversitas AirlanggaSurabayaIndonesia department of mathematics Universitas Islam Negeri SalatigaSalatigaIndonesia department of Epidemiology BiostatisticsPopulation and Health PromotionFaculty of Public HealthUniversitas AirlanggaSurabayaIndonesia department of mathematics Faculty of Mathematics and Natural SciencesUniversitas IndonesiaDepokIndonesia department of mathematics and applied mathematics University of JohannesburgAuckland ParkSouth Africa department of applied sciences Emirates Aviation UniversityUnited Arab Emirates

This paper presents and examines a COVID-19 model that takes comorbidities and up to three vaccine doses into *** analyze the stability of the equilibria,examine herd immunity,and conduct a sensitivity analysis validated by data on COVID-19 in *** disease-free equilibrium is locally and globally asymptotically stable whenever the basic reproduction number is less than one,while an endemic equilibrium exists and is globally asymptotically stable when the number is greater than ***,the model incorporates two effective measures,namely public education and enhanced medical care,to determine the most advantageous approach for mitigating the transmission of the *** optimal control model is then determined using Pontryagin’s maximum *** integrated control strategy is the best method for reliably safeguarding the general population against COVID-19 *** evaluations and numerical simulations corroborate this conclusion.

关键词： COVID-19 Comorbidity Stability Herd immunity Optimal control Cost evaluation

The Gain Equation of a Helical Wiggler Free Electron Laser with Ion-Channel Guiding and/or an Axial Magnetic Field

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Chinese Physics Letters 2013年第3期30卷 56-59页

作者： Taghi Mohsenpour Hassan Ehsani Amri department of Physics Faculty of Basic SciencesMazandaran UniversityBabolsarIran department of Physics Islamic Azad UniversityNour BranchIran

Electron motion in the combined ion-channel,helical wiggler and axial magnetic fields is analyzed in the absence of a radiation *** analysis of the gain equation in a free-electron laser is *** calculations are made to illustrate the effects of the two electron-beam guiding devices on the gain when applied separately and simultaneously.

关键词： Electron Wiggler Channel

Ground states for quasilinear equations of N-Laplacian type with critical exponential growth and lack of compactness

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Science China mathematics 2024年

作者： Sitong Chen Dongdong Qin Vicen?iu D.Rǎdulescu Xianhua Tang School of mathematics and statistics Hunan Key Laboratory of Analytical Mathematics and ApplicationsCentral South University faculty of applied mathematics AGH University of Kraków department of mathematics University of Craiova

In this paper,（i） we present unified approaches to studying the existence of ground state solutions and mountain-pass type solutions for the following quasilinear equation:-△Nu + V（x）|u|N-2u = f（u） in RN, N≥2 in three different cases allowing the potential V ∈ C（RN, R） to be periodic, radially symmetric, or asymptotically constant, where △Nu := div(|▽u|N-2▽u) and f has critical exponential growth;（ii） two new compactness lemmas in W1,N（RN） for general nonlinear functionals are established, which generalize the ones obtained in the radially symmetric space Wrad1,N（RN）;（iii） based on some key observations, we construct a special path allowing us to control the mountain-pass minimax level by a fine threshold under which the compactness can be restored for the critical case. In particular, some delicate analyses are developed to overcome non-standard difficulties due to both the quasilinear characteristic of the equation and the lack of compactness aroused by the critical exponential growth of f. Our results extend and improve the ones of Alves et al.（2012）, Ibrahim et al.（2015）(N = 2), and Masmoudi and Sani（2015）(N≥3) for the constant potential case, Alves and Figueiredo（2009） for the periodic potential case, Lam and Lu（2012） and Yang（2012） for the coercive potential case, and Chen et al.（Sci China Math, 2021） for the degenerate potential case, which are totally new even for the simpler semilinear case of N = 2. We believe that our approaches and strategies may be adapted and modified to attack more variational problems with critical exponential growth.

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Dynamical Transmission of Coronavirus Model with Analysis and Simulation

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Computer Modeling in Engineering & sciences 2021年第5期127卷 753-769页

作者： Muhammad Farman Ali Akgul Aqeel Ahmad Dumitru Baleanu Muhammad Umer Saleem department of mathematics and statistics University of LahoreLahore54590Pakistan faculty of Art and Science Department of MathematicsSiirt UniversitySiirt56100Turkey department of mathematics Cankaya UniversityAnkara06530Turkey Institute of Space sciences MagureleR76900Romania department of Medical Research China Medical UniversityTaichung40402Taiwan department of mathematics University of EducationLahore54770Pakistan

COVID-19 acts as a serious challenge to the whole *** data of COVID-19 is collected through media and web sources to analyze and investigate a system of nonlinear ordinary differential equation to understand the outbreaks of this epidemic *** analyze the diseases free and endemic equilibrium point including stability of the *** certain threshold value of the basic reproduction number R0 is found to observe whether population is in disease free state or endemic ***,the epidemic peak has been obtained and we expect a considerable number of ***,some numerical results are presented which show the effect of parameters estimation and different step size on our obtained solutions at the real data of some countries to check the actual behavior of the COVID-19 at different countries.

关键词： Epidemic model COVID-19 parameter estimation reproductive number stability analysis

Traditional rice-based fermented products:Insight into their probiotic diversity and probable health benefits

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Food Bioscience 2022年第6期50卷 52-70页

作者： Shruti Mishra S.Mithul Aravind Pratiksha Charpe Said Ajlouni C.Senaka Ranadheera S.Chakkaravarthi department of basic and applied sciences National Institute of Food Technology and Entrepreneurship ManagementHaryanaIndia School of Agriculture and Food Faculty of Veterinary and Agricultural SciencesThe University of MelbourneParkvilleVIC3010Australia

Various fermented foods and beverages are considered as representations of the traditional and cultural heritage of *** fermented products have been enjoyed worldwide since time *** products are popular due to their enhanced sensory attributes and probable health benefits,owing to the microorganisms and biochemical changes involved during ***,one of the popularly consumed cereal,forms a staple diet of many people across the globe especially Asia,Latin America and parts of *** traditional/ethnic fermented foods and beverages have been prepared from rice,since *** to urbanization and change in lifestyles,traditional rice based fermented products are losing its ***,there is an alarming need to explore these traditional food items scientifically to understand the relation among the fermented foods,microorganisms involved and their clinical studies assisted health *** from conventional rice,pigmented rice varieties have the potential to be used as raw material in production of rice based fermented products,because of their phytochemical contents,that increase by many folds due to *** review is intended to assess an overview of the nutritional composition of various rice varieties,probiotics in fermented rice-based products,their intervention in improving health and possible applications in the food and beverage sectors,to regain the lost popularity of these ethnic products.

关键词： Fermented food Health benefits Pigmented rice varieties Prebiotics Probiotics Rice

Investigation of fission fragments average spin based on four dimensional Langevin dynamical model

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Chinese Physics C 2017年第2期41卷 124-131页

作者： D.Naderi M.Salimi department of Physics Faculty of Basic Sciences Razi University P.O.Box 67149 Kermanshah Iran

We applied the four dimensional Langevin dynamical model to investigate the average spin of fission fragments. Elongation, neck thickness, asymmetry parameter, and the orientation degree of freedom（K coordinate）are the four dimensions of the dynamical model. We assume that the collective modes depend on the emission angle of the fragments, then different parameters related to the average spin of fission fragments are calculated *** angle dependence of average spin of fission fragments is investigated by calculating the spin at angles 90？and165？. Also, the obtained results based on the transition state model at scission point are presented. One can obtain better agreement between the results of the dynamical model and experimental data in comparison with the results of the transition state model.

关键词： Langevin equations average spin fission fragments

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Numerical investigations to design a novel model based on the fifth order system of Emden–Fowler equations

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Theoretical & applied Mechanics Letters 2020年第5期10卷 333-342页

作者： Zulqurnain Sabir Mehmet Giyas Sakar Manshuk Yeskindirova Onur Saldir department of mathematics and statistics Hazara UniversityMansehraPakistan department of mathematics Faculty of SciencesYuzuncu Yil UniversityVanTurkey department of Translation Theory and Practice L.N.Gumilyov Eurasian National UniversityKazakhstan

The aim of the present study is to design a new fifth order system of Emden–Fowler equations and related four types of the *** standard second order form of the Emden–Fowler has been used to obtain the new *** shape factor that appear more than one time discussed in detail for every case of the designed *** singularity atη=0 at one point or multiple points is also discussed at each type of the *** validation and correctness of the new designed model,one example of each type based on system of fifth order Emden–Fowler equations are provided and numerical solutions of the designed equations of each type have been obtained by using variational iteration *** comparison of the exact results and present numerical outcomes for solving one problem of each type is presented to check the accuracy of the designed model.

关键词： Fifth order Emden-Fowler system Multiple singularity Shape factor Numerical experimentations Variational iteration scheme

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Survey on Multi-period Mean-Variance Portfolio Selection Model

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Journal of the Operations Research Society of China 2022年第3期10卷 599-622页

作者： Xiang-Yu Cui Jian-Jun Gao Xun Li Yun Shi School of statistics and Management Shanghai University of Finance and EconomicsShanghai200433China School of Information Management and Engineering Shanghai University of Finance and EconomicsShanghai200433China department of applied mathematics The Hong Kong Polytechnic UniversityHong KongChina Academy of statistics and Interdisciplinary sciences Faculty of Economics and ManagementEast China Normal UniversityShanghai200062China

Due to the non-separability of the variance term,the dynamic mean-variance(MV)portfolio optimization problem is inherently difficult to solve by dynamic *** and Ng(Math Finance 10(3):387-406,2000)and Zhou and Li(Appl Math Optim 42(1):19-33,2000)develop the pre-committed optimal policy for such a problem using the embedding *** this line of research,researchers have extensively studied the MV portfolio selection model through the inclusion of more practical investment constraints,realistic market assumptions and various financial *** the principle of optimality no longer holds,the pre-committed policy suffers from the time-inconsistent issue,i.e.,the optimal policy computed at the intermediate time t is not consistent with the optimal policy calculated at any time before time *** time inconsistency of the dynamic MV model has become an important yet challenging research *** paper mainly focuses on the multi-period mean–variance(MMV)portfolio optimization problem,reviews the essential extensions and highlights the critical development of time-consistent policies.

关键词： Multi-period mean-variance Investment constraints Time inconsistency

On Symmetric Cayley Graphs of Valency Eleven

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Algebra Colloquium 2021年第2期28卷 309-318页

作者： Bo Ling Bengong Lou Li Ma Xue Yu School of mathematics and Computer sciences Yunnan Minzu University Kunming 650504China School of mathematics and statistics Yunnan University Kunming 650031China College of mathematics and statistics Qujing Normal University QujingYunnan 655011China department of mathematics Henan Institute of Science and Technology XinxiangHenan 453003China

A Cayley graph Г=Cay(G,S)is said to be normal if G is normal in Aut Г.In this paper,we investigate the normality problem of the connected 11-valent symmetric Cayley graphs Г of finite nonabelian simple groups G,where the vertex stabilizer A_(u) is soluble for A=Aut Г and v∈∨Г.We prove that either Г is normal or G=A_(5),A_(10),A_(54),A_(274),A_(549) or A_(1099).Further,11-valent symmetric nonnormal Cayley graphs of As,A54 and A274 are *** provides some more examples of nonnormal 11-valent symmetric Cayley graphs of finite nonabelian simple groups after the first graph of this kind(of valency 11)was constructed by Fang,Ma and Wang in 2011.

关键词： nonabelian simple group normal Cayley graph symmetric graph