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Fuzzy Dynamic Optimal Model for COVID-19 Epidemic in India Based on Granular Differentiability
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作者 KHATUA Debnarayan DE Anupam +3 位作者 KAR Samarjit SAMANTA Eshan SEKH Arif Ahmed GUHA ADHYA Debashree 《Journal of Shanghai Jiaotong university(Science)》 2025年第3期545-560,共16页
The pandemic SARS-CoV-2 has become an undying virus to spread a sustainable disease named COVID-19 for upcoming few years.Mortality rates are rising rapidly as approved drugs are not yet available.Isolation from the i... The pandemic SARS-CoV-2 has become an undying virus to spread a sustainable disease named COVID-19 for upcoming few years.Mortality rates are rising rapidly as approved drugs are not yet available.Isolation from the infected person or community is the preferred choice to protect our health.Since humans are the only carriers,it might be possible to control the positive rate if the infected population or host carriers are isolated from each other.Isolation alone may not be a proper solution.These are the resolutions of previous research work carried out on COVID-19 throughout the world.The present scenario of the world and public health is knocking hard with a big question of critical uncertainty of COVID-19 because of its imprecise database as per daily positive cases recorded all over the world and in India as well.In this research work,we have pre-sented an optimal control model for COVID-19 using granular differentiability based on fuzzy dynamical systems.In the first step,we created a fuzzy Susceptible-Exposed-Infected-Asymptomatic-Hospitalized-Recovered-Death(SEIAHRD)model for COVID-19,analyzed it using granular differentiability,and reported disease dynamics for time-independent disease control parameters.In the second step,we upgraded the fuzzy dynamical system and granular differentiability model related to time-dependent disease control parameters as an optimal control problem invader.Theoretical studies have been validated with some practical data from the epidemic COVID-19 related to the Indian perspective during first wave and early second wave. 展开更多
关键词 COVID-19 ASYMPTOMATIC SUSCEPTIBLE fuzzy dynamical system granular differentiability
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GÂTEAUX DIRECTIONAL DIFFERENTIABILITY OF THE GENERALIZED METRIC PROJECTION IN BANACH SPACES
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作者 Jinlu LI 《Acta Mathematica Scientia》 2025年第4期1597-1618,共22页
Let X be a real uniformly convex and uniformly smooth Banach space and C a nonempty closed and convex subset of X.Let Π_(C):X→C denote the generalized metric projection operator introduced by Alber in[1].In this pap... Let X be a real uniformly convex and uniformly smooth Banach space and C a nonempty closed and convex subset of X.Let Π_(C):X→C denote the generalized metric projection operator introduced by Alber in[1].In this paper,we define the Gâteaux directional differentiability of Π_(C).We investigate some properties of the Gâteaux directional differentiability of Π_(C).In particular,if C is a closed ball,or a closed and convex cone(including proper closed subspaces),or a closed and convex cylinder,then,we give the exact representations of the directional derivatives of Π_(C).By comparing the results in[12]and this paper,we see the significant difference between the directional derivatives of the generalized metric projection operator Π_(C) and the Gâteaux directional derivatives of the standard metric projection operator PC. 展开更多
关键词 uniformly convex and uniformly smooth Banach space the generalized metric projection directional differentiability of the generalized metric projection directional derivative of the generalized metric projection
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Some Equivalent Conditions for the Differentiability of Continuous Gauge Functions on Banach Space
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作者 南朝勋 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第4期84-88,共5页
In this paper,some equivalent conditions for differentiability of condtinuous gauge function are given.
关键词 gauge function SUBGRADIENT Gauteaux differentiability Frechet differentiability
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DIFFERENTIABILITY OF CONVEX FUNCTIONS AND ASPLUND SPACES 被引量:3
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作者 程立新 张风 《Acta Mathematica Scientia》 SCIE CSCD 1995年第2期171-179,共9页
Characterizations of differentiability are obtained for continuous convex functions defined on nonempty open convex sets of Banach spaces as a generalization and application of a mumber of mathematicians several years... Characterizations of differentiability are obtained for continuous convex functions defined on nonempty open convex sets of Banach spaces as a generalization and application of a mumber of mathematicians several years effort, and a characteristic theorem is given for Banach spaces which are (weak) Asplund spaces. 展开更多
关键词 CONVEX FUNCTION differentiability BANACH SPACE ASPLUND SPACE
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Differentiability of Convex Functions in Locally Convex Spaces(Ⅰ)──Continuous Convex Functions and Gateaux Differentiability 被引量:3
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作者 吴从 程立新 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1994年第1期7-12,共6页
The aim of this paper is to investigate the differentiability(Gateaux differentiabllity and subdifferentiability) of continuous convex functions on locally convex spaces and to study the behaviour of some important re... The aim of this paper is to investigate the differentiability(Gateaux differentiabllity and subdifferentiability) of continuous convex functions on locally convex spaces and to study the behaviour of some important results for this research area in locally convex spaces. 展开更多
关键词 ss: differentiability CONVEX function LOCALLY CONVEX space
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ON TERM BY TERM DYADIC DIFFERENTIABILITY OF WALSH-KACZMARZ SERIES 被引量:2
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作者 Gyorgy Gdt(College of Nyiregyhaza, Hungary) 《Analysis in Theory and Applications》 2003年第1期55-75,共21页
The aim of this paper is to prove the following theorem concerning the term by term differentiation the-orem of Walsh-Kaczmarz series. Let (ck) be a decreasing real sequence withare integrable functions and f(x) is a.... The aim of this paper is to prove the following theorem concerning the term by term differentiation the-orem of Walsh-Kaczmarz series. Let (ck) be a decreasing real sequence withare integrable functions and f(x) is a. e. dyadic (or Butzer and Wagner) differentiate withThe function Kk means the kth Walsh-Kaczmarz function. 展开更多
关键词 dyadic (Butzer and Wagner) differentiability Walsh-Kaczmarz series monotone coefficients Fejer kernels
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ON THE PRODUCT OF GTEAUX DIFFERENTIABILITY LOCALLY CONVEX SPACES 被引量:1
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作者 沈喜生 程立新 《Acta Mathematica Scientia》 SCIE CSCD 2005年第3期395-400,共6页
A locally convex space is said to be a Gateaux differentiability space (GDS) provided every continuous convex function defined on a nonempty convex open subset D of the space is densely Gateaux differentiable in .D.Th... A locally convex space is said to be a Gateaux differentiability space (GDS) provided every continuous convex function defined on a nonempty convex open subset D of the space is densely Gateaux differentiable in .D.This paper shows that the product of a GDS and a family of separable Prechet spaces is a GDS,and that the product of a GDS and an arbitrary locally convex space endowed with the weak topology is a GDS. 展开更多
关键词 Convex function locally convex space Gateaux differentiability space
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DIFFERENTIABILITY OF C_0-SEMIGROUPS WITH APPLICATION
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作者 金振东 喻文焕 +1 位作者 靳展 王辅敏 《Transactions of Tianjin University》 EI CAS 1999年第2期25-29,共5页
This paper considers the differentiability of C 0 semigroups with respect to (w.r.t.) parameters contained in their infinitesimal generators.It is proved that the generalized continuity and strong differentiability ... This paper considers the differentiability of C 0 semigroups with respect to (w.r.t.) parameters contained in their infinitesimal generators.It is proved that the generalized continuity and strong differentiability of their infinitesimal generators w.r.t.parameters imply the differentiability of the C 0 semigroups.The results are applied to the differentiability of the solution of a linear delay differential equation w.r.t.its delays. 展开更多
关键词 C 0 semigroup infinitesimal generator generalized continuity strongly Frechet differential dalay equation
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Differentiability of the Pritchard-Salamon systems with admissible state-feedback
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作者 于欣 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第4期311-314,共4页
Many papers on a wide range of control problems for Pritchard-Salamon systems have appeared and many of its important mathematical and system theoretical properties have been revealed. This paper deals with the differ... Many papers on a wide range of control problems for Pritchard-Salamon systems have appeared and many of its important mathematical and system theoretical properties have been revealed. This paper deals with the differentiability of the Pritchard-Salamon system with admissible state-feedback. Spectrum analysis showed that under definite condition, the unbounded perturbation semigroup of the Pritchard-Salamon system is eventually differentiable. 展开更多
关键词 C_0-semigroup differentiability Admissible operator Pritchard-Salamon systems PERTURBATION
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HOLDER CONTINUITY AND DIFFERENTIABILITY ON CONVERGING SUBSEQUENCES
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作者 Volker Elling 《Acta Mathematica Scientia》 SCIE CSCD 2012年第1期75-83,共9页
It is shown that an arbitrary function from D Rn to Rm will become C0,a-continuous in almost every x∈ D after restriction to a certain subset with limit pointx. For n 〉 m differentiability can be obtained. Example... It is shown that an arbitrary function from D Rn to Rm will become C0,a-continuous in almost every x∈ D after restriction to a certain subset with limit pointx. For n 〉 m differentiability can be obtained. Examples show the Ho1der exponent a=min{1,n/m}is optimal. 展开更多
关键词 Ho1der continuity Lipschitz continuity differentiability RESTRICTION weaksolution
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ON THE CONTINUITY AND DIFFERENTIABILITY OF AKIND OF FRACTAL INTERPOLATION FUNCTION
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作者 李红达 叶正麟 高行山 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第4期471-478,共8页
The sufficient conditions of Holder continuity of two kinds of fractal interpolation functions defined by IFS (Iterated Function System) were obtained. The sufficient and necessary condition for its differentiability ... The sufficient conditions of Holder continuity of two kinds of fractal interpolation functions defined by IFS (Iterated Function System) were obtained. The sufficient and necessary condition for its differentiability was proved. Its derivative was a fractal interpolation function generated by the associated IFS, if it is differentiable. 展开更多
关键词 FRACTAL interpolation function Holder continuity differentiability
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Differentiability of Functions on Spheres and Criterions of Convexity
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作者 CHEN Tingting GUO Qi 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2022年第4期273-280,共8页
Some basic concepts for functions defined on subsets of the unit sphere,such as the s-directional derivative,s-gradient and s-Gateaux and s-Frechet differentiability etc,are introduced and investigated.These concepts ... Some basic concepts for functions defined on subsets of the unit sphere,such as the s-directional derivative,s-gradient and s-Gateaux and s-Frechet differentiability etc,are introduced and investigated.These concepts are different from the usual ones for functions defined on subsets of Euclidean spaces,however,the results obtained here are very similar.Then,as applications,we provide some criterions of s-convexity for functions defined on unit spheres which are improvements or refinements of some known results. 展开更多
关键词 spherical convexity spherically convex function Gateaux and Frechet differentiability criterion of convexity
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The differentiability of solutions for elliptic equations which degenerate on part of the boundary of a convex domain
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作者 SONG Jia-xin CAO Yi 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2018年第4期421-435,共15页
In this paper,we study the differentiability of solutions on the boundary for equartions of type L;u=;u/x;+|x|;;u/y;=f(x,y),where λ is an arbitrary positive number. By introducing a proper metric that is related to... In this paper,we study the differentiability of solutions on the boundary for equartions of type L;u=;u/x;+|x|;;u/y;=f(x,y),where λ is an arbitrary positive number. By introducing a proper metric that is related to the elliptic operator L;, we prove the differentiability on the boundary when some well-posed boundary conditions are satisfied. The main difficulty is the construction of new barrier functions in this article. 展开更多
关键词 elliptic equations convex domain differentiability
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Smulyan Lemma and Differentiability of the Support Function
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作者 Ildar Sadeqi Sima Hassankhali 《Analysis in Theory and Applications》 CSCD 2018年第4期348-357,共10页
The purpose of this paper is to verify the Smulyan lemma for the support function, and also the Gateaux differentiability of the support function is studied on its domain. Moreover, we provide a characterization of Fr... The purpose of this paper is to verify the Smulyan lemma for the support function, and also the Gateaux differentiability of the support function is studied on its domain. Moreover, we provide a characterization of Frechet differentiability of the support function on the extremal points. 展开更多
关键词 Frechet and Gateaux differentiability support function strict convexity Smulyan lemma
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Differentiability of Convex Functions in Locally Convex Spaces(Ⅱ)──Frechet
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作者 王晓敏 程立新 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1997年第1期1-4,共4页
DifferentiabilityofConvexFunctionsinLocallyConvexSpaces(II)──FrechetDifferentiabilityWUCongxinWANGXiaominCHE... DifferentiabilityofConvexFunctionsinLocallyConvexSpaces(II)──FrechetDifferentiabilityWUCongxinWANGXiaominCHENGLixin吴从aaay,王晓敏... 展开更多
关键词 王晓 differentiability of Convex Functions in Locally Convex Spaces Frechet
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DIFFERENTIABILITY FOR THE HIGH DIMENSIONAL POLYNOMIAL-LIKE ITERATIVE EQUATION 被引量:9
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作者 李晓培 邓圣福 《Acta Mathematica Scientia》 SCIE CSCD 2005年第1期130-136,共7页
This paper studies the smoothness of solutions of the higher dimensional polynomial-like iterative equation. The methods given by Zhang Weinian([7]) and by Kulczvcki M, Tabor j.([3]) are improved by constructing a new... This paper studies the smoothness of solutions of the higher dimensional polynomial-like iterative equation. The methods given by Zhang Weinian([7]) and by Kulczvcki M, Tabor j.([3]) are improved by constructing a new operator for the structure of the equation in order to apply fixed point theorems. Existence, uniqueness and stability of continuously differentiable solutions are given. 展开更多
关键词 ITERATION fixed point theorem differentiable solutions existence UNIQUENESS stability
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BIOLOGICAL INVASION PROBLEM WITH FREE BOUNDARY NONLOCAL DIFFUSION EQUATION 被引量:2
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作者 HE Yu-rong ZHANG Ya-rong 《数学杂志》 2025年第1期48-56,共9页
In order to better describe the phenomenon of biological invasion,this paper introduces a free boundary model of biological invasion.Firstly,the right free boundary is added to the equation with logistic terms.Secondl... In order to better describe the phenomenon of biological invasion,this paper introduces a free boundary model of biological invasion.Firstly,the right free boundary is added to the equation with logistic terms.Secondly,the existence and uniqueness of local solutions are proved by the Sobolev embedding theorem and the comparison principle.Finally,according to the relevant research data and contents of red fire ants,the diffusion area and nest number of red fire ants were simulated without external disturbance.This paper mainly simulates the early diffusion process of red fire ants.In the early diffusion stage,red fire ants grow slowly and then spread over a large area after reaching a certain number. 展开更多
关键词 Free boundary biological invasion differential equation
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强瞬变热环境下高温结构快速变温跟踪控制试验方法及验证
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作者 李振磊 李博琳 +4 位作者 李果 包绍宸 丁水汀 夏舒洋 左亮亮 《航空动力学报》 北大核心 2025年第4期140-148,共9页
针对先进航空发动机高温结构强瞬变热环境试验模拟需求,开发了快速变温跟踪控制试验方法并搭建了试验系统,对比两种面向不同温度变化率的控制方法,分别形成基于可编程控制器Arduino的单回路双作动proportion integration differentiatio... 针对先进航空发动机高温结构强瞬变热环境试验模拟需求,开发了快速变温跟踪控制试验方法并搭建了试验系统,对比两种面向不同温度变化率的控制方法,分别形成基于可编程控制器Arduino的单回路双作动proportion integration differentiation(PID)控制方法及基于智能仪表Eurotherm的双回路多段PID控制方法。通过仿真工具Simulink进行参数整定验证,利用该试验系统开展了不同速率目标与试样类型的快速变温跟踪控制试验。结果表明:航空发动机涡轮盘材料GH4169在300~650℃范围内三角波及梯形波目标下两种控制器控制误差均低于6.83%,控制效果平滑精准,空心薄壁管可控温度变化率达到100℃/s,基于Eurotherm的控制方法精度与适用性更具优势。 展开更多
关键词 温度控制 温度跟踪 proportion integration differentiation(PID) 强瞬变热环境 ARDUINO Eurotherm
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Postnatal development of rat retina:a continuous observation and comparison between the organotypic retinal explant model and in vivo development 被引量:1
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作者 Baoqi Hu Rui Wang +8 位作者 Hanyue Zhang Xiou Wang Sijia Zhou Bo Ma Yan Luan Xin Wang Xinlin Chen Zhichao Zhang Qianyan Kang 《Neural Regeneration Research》 SCIE CAS 2025年第3期900-912,共13页
The organotypic retinal explant culture has been established for more than a decade and offers a range of unique advantages compared with in vivo experiments and cell cultures.However,the lack of systematic and contin... The organotypic retinal explant culture has been established for more than a decade and offers a range of unique advantages compared with in vivo experiments and cell cultures.However,the lack of systematic and continuous comparison between in vivo retinal development and the organotypic retinal explant culture makes this model controversial in postnatal retinal development studies.Thus,we aimed to verify the feasibility of using this model for postnatal retinal development studies by comparing it with the in vivo retina.In this study,we showed that postnatal retinal explants undergo normal development,and exhibit a consistent structure and timeline with retinas in vivo.Initially,we used SOX2 and PAX6 immunostaining to identify retinal progenitor cells.We then examined cell proliferation and migration by immunostaining with Ki-67 and doublecortin,respectively.Ki-67-and doublecortin-positive cells decreased in both in vivo and explants during postnatal retinogenesis,and exhibited a high degree of similarity in abundance and distribution between groups.Additionally,we used Ceh-10 homeodomain-containing homolog,glutamate-ammonia ligase(glutamine synthetase),neuronal nuclei,and ionized calcium-binding adapter molecule 1 immunostaining to examine the emergence of bipolar cells,Müller glia,mature neurons,and microglia,respectively.The timing and spatial patterns of the emergence of these cell types were remarkably consistent between in vivo and explant retinas.Our study showed that the organotypic retinal explant culture model had a high degree of consistency with the progression of in vivo early postnatal retina development.The findings confirm the accuracy and credibility of this model and support its use for long-term,systematic,and continuous observation. 展开更多
关键词 bipolar cells differentiation in vivo microglia Müller glia organotypic retinal explant culture postnatal retina development proliferation retinal progenitor cells
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Müller cells are activated in response to retinal outer nuclear layer degeneration in rats subjected to simulated weightlessness conditions 被引量:1
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作者 Yuxue Mu Ning Zhang +7 位作者 Dongyu Wei Guoqing Yang Lilingxuan Yao Xinyue Xu Yang Li Junhui Xue Zuoming Zhang Tao Chen 《Neural Regeneration Research》 SCIE CAS 2025年第7期2116-2128,共13页
A microgravity environment has been shown to cause ocular damage and affect visual acuity,but the underlying mechanisms remain unclear.Therefore,we established an animal model of weightlessness via tail suspension to ... A microgravity environment has been shown to cause ocular damage and affect visual acuity,but the underlying mechanisms remain unclear.Therefore,we established an animal model of weightlessness via tail suspension to examine the pathological changes and molecular mechanisms of retinal damage under microgravity.After 4 weeks of tail suspension,there were no notable alterations in retinal function and morphology,while after 8 weeks of tail suspension,significant reductions in retinal function were observed,and the outer nuclear layer was thinner,with abundant apoptotic cells.To investigate the mechanism underlying the degenerative changes that occurred in the outer nuclear layer of the retina,proteomics was used to analyze differentially expressed proteins in rat retinas after 8 weeks of tail suspension.The results showed that the expression levels of fibroblast growth factor 2(also known as basic fibroblast growth factor)and glial fibrillary acidic protein,which are closely related to Müller cell activation,were significantly upregulated.In addition,Müller cell regeneration and Müller cell gliosis were observed after 4 and 8 weeks,respectively,of simulated weightlessness.These findings indicate that Müller cells play an important regulatory role in retinal outer nuclear layer degeneration during weightlessness. 展开更多
关键词 glial fibrous acidic protein GLIOSIS Müller cells nerve growth factor neural differentiation neurodegeneration proteomic retinal degeneration retinal outer nuclear layer simulated weightlessness
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