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Comparative Studies between Picard’s and Taylor’s Methods of Numerical Solutions of First Ordinary Order Differential Equations Arising from Real-Life Problems
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作者 Khalid Abd Elrazig Awad Alla Elnour 《Journal of Applied Mathematics and Physics》 2024年第3期877-896,共20页
To solve the first-order differential equation derived from the problem of a free-falling object and the problem arising from Newton’s law of cooling, the study compares the numerical solutions obtained from Picard’... To solve the first-order differential equation derived from the problem of a free-falling object and the problem arising from Newton’s law of cooling, the study compares the numerical solutions obtained from Picard’s and Taylor’s series methods. We have carried out a descriptive analysis using the MATLAB software. Picard’s and Taylor’s techniques for deriving numerical solutions are both strong mathematical instruments that behave similarly. All first-order differential equations in standard form that have a constant function on the right-hand side share this similarity. As a result, we can conclude that Taylor’s approach is simpler to use, more effective, and more accurate. We will contrast Rung Kutta and Taylor’s methods in more detail in the following section. 展开更多
关键词 First-Order Differential Equations Picard Method Taylor Series Method Numerical solutions Numerical Examples MATLAB Software
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Kangfuxin solution alleviates esophageal stenosis after endoscopic submucosal dissection:A natural ingredient strategy
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作者 Xin Zhou Dan Ma +7 位作者 Yi-Xiang He Jing Jin Hong-Lian Wang Yun-Feng Wang Fan Yang Jian-Qin Liu Jie Chen Zhi Li 《World Journal of Gastroenterology》 SCIE CAS 2025年第1期110-125,共16页
BACKGROUND Esophageal stricture ranks among the most significant complications following endoscopic submucosal dissection(ESD).Excessive fibrotic repair is a typical pathological feature leading to stenosis after ESD.... BACKGROUND Esophageal stricture ranks among the most significant complications following endoscopic submucosal dissection(ESD).Excessive fibrotic repair is a typical pathological feature leading to stenosis after ESD.AIM To examine the effectiveness and underlying mechanism of Kangfuxin solution(KFX)in mitigating excessive fibrotic repair of the esophagus post-ESD.METHODS Pigs received KFX at 0.74 mL/kg/d for 21 days after esophageal full circumferential ESD.Endoscopic examinations occurred on days 7 and 21 post-ESD.In vitro,recombinant transforming growth factor(TGF)-β1(5 ng/mL)induced a fibrotic microenvironment in primary esophageal fibroblasts(pEsF).After 24 hours of KFX treatment(at 1.5%,1%,and 0.5%),expression ofα-smooth muscle actin-2(ACTA2),fibronectin(FN),and type collagen I was assessed.Profibrotic signaling was analyzed,including TGF-β1,Smad2/3,and phosphor-smad2/3(p-Smad2/3).RESULTS Compared to the Control group,the groups treated with KFX and prednisolone exhibited reduced esophageal stenosis,lower weight loss rates,and improved food tolerance 21 d after ESD.After treatment,Masson staining revealed thinner and less dense collagen fibers in the submucosal layer.Additionally,the expression of fibrotic effector molecules was notably inhibited.Mechanistically,KFX downregulated the transduction levels of fibrotic functional molecules such as TGF-β1,Smad2/3,and p-Smad2/3.In vitro,pEsF exposed to TGF-β1-induced fibrotic microenvironment displayed increased fibrotic activity,which was reversed by KFX treatment,leading to reduced activation of ACTA2,FN,and collagen I.The 1.5%KFX treatment group showed decreased expression of p-Smad 2/3 in TGF-β1-activated pEsF.CONCLUSION KFX showed promise as a therapeutic option for post-full circumferential esophageal ESD strictures,potentially by suppressing fibroblast fibrotic activity through modulation of the TGF-β1/Smads signaling pathway. 展开更多
关键词 Kangfuxin solution Natural component Endoscopic submucosal dissection Esophagus stricture Fibrosis
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Normalized Solutions of Nonlinear Choquard Equations with Nonconstant Potential
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作者 LI Nan XU Liping 《应用数学》 北大核心 2025年第1期14-29,共16页
In this paper,we mainly focus on a type of nonlinear Choquard equations with nonconstant potential.Under appropriate hypotheses on potential function and nonlinear terms,we prove that the above Choquard equation with ... In this paper,we mainly focus on a type of nonlinear Choquard equations with nonconstant potential.Under appropriate hypotheses on potential function and nonlinear terms,we prove that the above Choquard equation with prescribed 2-norm has some normalized solutions by introducing variational methods. 展开更多
关键词 Nonlinear Choquard equation Potential function Variational method Normalized solution
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General Solutions’ Laws of Nonlinear Partial Differential Equations
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作者 Honglai Zhu 《Journal of Applied Mathematics and Physics》 2025年第1期166-208,共43页
In previous papers, we proposed the important Ztransformations and obtained general solutions to a large number of linear and quasi-linear partial differential equations for the first time. In this paper, we will use ... In previous papers, we proposed the important Ztransformations and obtained general solutions to a large number of linear and quasi-linear partial differential equations for the first time. In this paper, we will use the Z1transformation to get the general solutions of some nonlinear partial differential equations for the first time, and use the general solutions to obtain the exact solutions of some typical definite solution problems. 展开更多
关键词 TRANSFORMATION Nonlinear Partial Differential Equations Analytical solution General solution Definite solution Problems
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Global Piecewise Analysis of HIV Model with Bi-Infectious Categories under Ordinary Derivative and Non-Singular Operator with Neural Network Approach
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作者 Ghaliah Alhamzi Badr Saad TAlkahtani +1 位作者 Ravi Shanker Dubey Mati ur Rahman 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期609-633,共25页
This study directs the discussion of HIV disease with a novel kind of complex dynamical generalized and piecewise operator in the sense of classical and Atangana Baleanu(AB)derivatives having arbitrary order.The HIV i... This study directs the discussion of HIV disease with a novel kind of complex dynamical generalized and piecewise operator in the sense of classical and Atangana Baleanu(AB)derivatives having arbitrary order.The HIV infection model has a susceptible class,a recovered class,along with a case of infection divided into three sub-different levels or categories and the recovered class.The total time interval is converted into two,which are further investigated for ordinary and fractional order operators of the AB derivative,respectively.The proposed model is tested separately for unique solutions and existence on bi intervals.The numerical solution of the proposed model is treated by the piece-wise numerical iterative scheme of Newtons Polynomial.The proposed method is established for piece-wise derivatives under natural order and non-singular Mittag-Leffler Law.The cross-over or bending characteristics in the dynamical system of HIV are easily examined by the aspect of this research having a memory effect for controlling the said disease.This study uses the neural network(NN)technique to obtain a better set of weights with low residual errors,and the epochs number is considered 1000.The obtained figures represent the approximate solution and absolute error which are tested with NN to train the data accurately. 展开更多
关键词 HIV infection model qualitative scheme approximate solution piecewise global operator neural network
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N-Fold Darboux Transformation and Various Solutions for the Coupled mKdV Equations
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作者 Chunmei Fang 《Journal of Applied Mathematics and Physics》 2025年第2期381-391,共11页
In this paper, we get the N-fold Darboux transformation with multi-parameters for the coupled mKdV equations with the help of a guage transformation of the spectral problem. As an application, some new multi-soliton s... In this paper, we get the N-fold Darboux transformation with multi-parameters for the coupled mKdV equations with the help of a guage transformation of the spectral problem. As an application, some new multi-soliton solutions and complexiton solutions are obtained from choosing the appropriate seed solution. All obtained solutions and N-fold Darboux transformations are expressed using the Vandermonde-like determinants. 展开更多
关键词 The N-fold Darboux Transformation The Coupled mKdV Equations Multi-Soliton solutions Complexiton solutions
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Conservation Laws and Particular Solutions for a Keller-Segel Model
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作者 Luyun Chen Jie Lou 《Advances in Pure Mathematics》 2025年第2期107-118,共12页
This work focuses on a Keller-Segel chemotaxis model, with an emphasis on its conservation laws. Through a new approach combined with the multiplier method, called the mixed method, we obtain conservation vectors that... This work focuses on a Keller-Segel chemotaxis model, with an emphasis on its conservation laws. Through a new approach combined with the multiplier method, called the mixed method, we obtain conservation vectors that are related and unrelated to symmetric information. In addition, some exact solutions with particular forms are obtained according to the method of conservation laws. These particular solutions are different from the group-invariant solutions. 展开更多
关键词 Keller-Segel Model Conservation Laws Mixed Method Exact solutions
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Synergistic effect of infinite and finite solid solution enabling ultrathin Li-Cu-Ag alloy toward advanced Li metal anode
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作者 Xiao-Xiao Chen Hao Huang +6 位作者 Lin-Yun Yi Zi-Hao Wang Zhi-Cui Song Jian-Xiong Xing Chao-Hui Wei Ai-Jun Zhou Jing-Ze Li 《Rare Metals》 2025年第1期121-134,共14页
Ultrathin Li-rich Li-Cu binary alloy has become a competitive anode material for Li metal batteries of high energy density.However,due to the poor-lithiophilicity of the single skeleton structure of Li-Cu alloy,it has... Ultrathin Li-rich Li-Cu binary alloy has become a competitive anode material for Li metal batteries of high energy density.However,due to the poor-lithiophilicity of the single skeleton structure of Li-Cu alloy,it has limitations in inducing Li nucleation and improving electrochemical performance.Hence,we introduced Ag species to Li-Cu alloy to form a 30μm thick Li-rich Li-Cu-Ag ternary alloy(LCA)anode,with Li-Ag infinite solid solution as the active phase,and Cu-based finite solid solutions as three-dimensional(3D)skeleton.Such nano-wire networks with LiCu4 and CuxAgy finite solid solution phases were prepared through a facile melt coating technique,where Ag element can act as lithiophilic specie to enhance the lithiophilicity of built-in skeleton,and regulate the deposition behavior of Li effectively.Notably,the formation of CuxAgy solid solution can strengthen the structural stability of the skeleton,ensuring the geometrical integrity of Li anode,even at the fully delithiated state.Meanwhile,the Li-Ag infinite solid solution phase can promote the Li plating/stripping reversibility of the LCA anode with an improved coulombic efficiency(CE).The synergistic effect between infinite and finite solid solutions could render an enhanced electrochemical performance of Li metal batteries.The LCA|LCA symmetric cells showed a long lifespan of over 600 h with stable polarization voltage of 40 mV,in 1 mA·cm^(-2)/1 mAh·cm^(-2).In addition,the full cells matching our ultrathin LCA anode with 17.2 mg·cm^(-2)mass loading of LiFePO4 cathode,can continuously operate beyond 110 cycles at 0.5C,with a high capacity retention of 91.5%.Kindly check and confirm the edit made in the article title. 展开更多
关键词 Li alloy anode Solid solution solution strengthening Lithiophilic skeleton Ternary alloy
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The N-periodic wave solutions to the N=1 supersymmetric Sawada–Kotera–Ramani equation
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作者 Pengcheng Xin Zhonglong Zhao Yu Wang 《Chinese Physics B》 2025年第2期207-213,共7页
The N-periodic wave solvability problem for the N=1 supersymmetric Sawada–Kotera–Ramani equation is considered by combining the Hirota's bilinear method and the super Riemann theta function. The constraint equat... The N-periodic wave solvability problem for the N=1 supersymmetric Sawada–Kotera–Ramani equation is considered by combining the Hirota's bilinear method and the super Riemann theta function. The constraint equations and unknown parameters are redefined, and the numerical calculation process of the N-periodic wave solutions is derived. It has been verified that under certain conditions, the asymptotic relations between N-periodic wave solutions and N-soliton solutions can be established. Some numerical solutions of three-periodic wave are presented. Under the influence of the Grassmann variable, the three-periodic wave solutions will generate an influence band in the middle region, and the amplitude becomes bigger as the distance from the influence band increases. 展开更多
关键词 SUPERSYMMETRY N-periodic wave solutions asymptotic relations
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Colorectal cancer early screening:Dilemmas and solutions
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作者 Di Wu Qi-Ying Song +4 位作者 Bai-Shu Dai Jie Li Xin-Xin Wang Jia-Yu Liu Tian-Yu Xie 《World Journal of Gastroenterology》 2025年第9期154-160,共7页
Colorectal cancer(CRC)is a prevalent malignancy worldwide,posing a significant public health concern.Mounting evidence has confirmed that timely early screening facilitates the detection of incipient CRC,thereby enhan... Colorectal cancer(CRC)is a prevalent malignancy worldwide,posing a significant public health concern.Mounting evidence has confirmed that timely early screening facilitates the detection of incipient CRC,thereby enhancing patient prognosis.Obviously,non-participation of asymptomatic individuals in screening programs hampers early diagnosis and may adversely affect long-term outcomes for CRC patients.In this letter,we provide a comprehensive overview of the current status of early screening practices,while also thoroughly examine the dilemmas and potential solutions associated with early screening for CRC.In response to these issues,we proffer a set of recommendations directed at governmental authorities and the general public,which focus on augmenting financial investment,establishing standardized screening protocols,advancing technological capabilities,and bolstering public awareness campaigns.The importance of collaborative efforts from various stakeholders cannot be overstated in the quest to enhance early detection rates and alleviate the societal burden of CRC. 展开更多
关键词 Colorectal cancer Early screening Asymptomatic candidates DILEMMAS solutionS
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MOUNTAIN-PASS SOLUTION FOR A KIRCHHOFF TYPE ELLIPTIC EQUATION
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作者 Lifu WENG Xu ZHANG Huansong ZHOU 《Acta Mathematica Scientia》 2025年第2期385-400,共16页
We are concerned with a nonlinear elliptic equation,involving a Kirchhoff type nonlocal term and a potential V(x),onℝ3.As is well known that,even in,H_(r)^(1)(R^(3)),the nonlinear term is a pure power form of∣u∣^(p−... We are concerned with a nonlinear elliptic equation,involving a Kirchhoff type nonlocal term and a potential V(x),onℝ3.As is well known that,even in,H_(r)^(1)(R^(3)),the nonlinear term is a pure power form of∣u∣^(p−1)u and V(x)≡1,it seems very difficult to apply the mountain-pass theorem to get a solution(i.e.,mountain-pass solution)to this kind of equation for all p∈(1,5),due to the difficulty of verifying the boundedness of the PalaisSmale sequence obtained by the mountain-pass theorem when p∈(1,3).In this paper,we find a new strategy to overcome this difficulty,and then get a mountain-pass solution to the equation for all p∈(1,5)and for both V(x)being constant and nonconstant.Also,we find a possibly optimal condition on V(x). 展开更多
关键词 elliptic equation ground state mountain-pass solution Kirchhoff equation
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Symplectic solutions for orthotropic micropolar plane stress problem
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作者 Long Chen Zhaofei Tang +1 位作者 Qiong Wu Qiang Gao 《Acta Mechanica Sinica》 2025年第1期106-127,共22页
The symplectic approach was utilized to derive solutions to the orthotropic micropolar plane stress problem.The Hamiltonian canonical equation was first obtained by applying Legendre’s transformation and the Hamilton... The symplectic approach was utilized to derive solutions to the orthotropic micropolar plane stress problem.The Hamiltonian canonical equation was first obtained by applying Legendre’s transformation and the Hamiltonian mixed energy variational principle.Then,by using the method of separation of variables,the eigenproblem of the corresponding homogeneous Hamiltonian canonical equation was derived.Subsequently,the corresponding eigensolutions for three kinds of homogeneous boundary conditions were derived.According to the adjoint symplectic orthogonality of the eigensolutions and expansion theorems,the solutions to this plane stress problem were expressed as a series expansion of these eigensolutions.The numerical results for the orthotropic micropolar plane stress problem under various boundary conditions were presented and validated using the finite element method,which confirmed the convergence and accuracy of the proposed approach.We also investigated the relationship between the size-dependent behaviour and material parameters using the proposed approach.Furthermore,this approach was applied to analyze lattice structures under an equivalent micropolar continuum approximation. 展开更多
关键词 Symplectic approach MICROPOLAR Orthotropic materials Size effect Analytical solution
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MULTIPLE SOLUTIONS FOR A HAMILTONIAN ELLIPTIC SYSTEM WITH SIGN-CHANGING PERTURBATION
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作者 Peng CHEN Longjiang GU Yan WU 《Acta Mathematica Scientia》 2025年第2期602-614,共13页
In this paper,we study the elliptic system{-Δu+V(x)u=|v|^(p-2)v-λ_(2)|v|^(s2-2)v,-Δu+V(x)v=|u|^(p-2)u-λ_(1)|u|^(s1-2)u,u,v∈H^(1)(R^(N))with strongly indefinite structure and sign-changing nonlinearity.We overcome... In this paper,we study the elliptic system{-Δu+V(x)u=|v|^(p-2)v-λ_(2)|v|^(s2-2)v,-Δu+V(x)v=|u|^(p-2)u-λ_(1)|u|^(s1-2)u,u,v∈H^(1)(R^(N))with strongly indefinite structure and sign-changing nonlinearity.We overcome the absence of the upper semi-continuity assumption which is crucial in traditional variational methods for strongly indefinite problems.By some new tools and techniques we proved the existence of infinitely many geometrically distinct solutions if parametersλ_(1),λ_(2)>0 small enough.To the best of our knowledge,our result seems to be the first result about infinitely many solutions for Hamiltonian system involving sign-changing nonlinearity. 展开更多
关键词 variational method strongly indefinite elliptic system multiple solutions signchanging nonlinearity
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In-Plane Static Analysis of Curved Nanobeams Using Exact-Solution-Based Finite Element Formulation
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作者 Omer Ekim Genel Hilal Koc Ekrem Tufekci 《Computers, Materials & Continua》 2025年第2期2043-2059,共17页
Due to their superior properties, the interest in nanostructures is increasing today in engineering. This study presents a new two-noded curved finite element for analyzing the in-plane static behaviors of curved nano... Due to their superior properties, the interest in nanostructures is increasing today in engineering. This study presents a new two-noded curved finite element for analyzing the in-plane static behaviors of curved nanobeams. Opposite to traditional curved finite elements developed by using approximate interpolation functions, the proposed curved finite element is developed by using exact analytical solutions. Although this approach was first introduced for analyzing the mechanical behaviors of macro-scale curved beams by adopting the local theory of elasticity, the exact analytical expressions used in this study were obtained from the solutions of governing equations that were expressed via the differential form of the nonlocal theory of elasticity. Therefore, the effects of shear strain and axial extension included in the analytical formulation are also inherited by the curved finite element developed here. The rigidity matrix and the consistent force vector are developed for a circular finite element. To demonstrate the applicability of the method, static analyses of various curved nanobeams subjected to different boundary conditions and loading scenarios are performed, and the obtained results are compared with the exact analytical ones. The presented study provides an accurate and low computational cost method for researchers to investigate the in-plane static behavior of curved nanobeams. 展开更多
关键词 Nonlocal elasticity finite element exact solution static analysis nanobeam curved
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HC-A solution limb perfusion alleviates liver damage induced by limb ischemia-reperfusion injury in pigs
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作者 Bowen Zhang Weixiang Ni +7 位作者 Qinglong Cai Huitao Ji Junhao Du Weixuan Hong Junwei Fang Lie Wang Yafeng Qi Chunhong Xiao 《Animal Models and Experimental Medicine》 2025年第3期421-428,共8页
Background:The aim of the study was to explore a feasible method for alleviating limb ischemia-reperfusion injury(LI/RI)through the use of a high-concentration citrate solution(HC-A solution)for limb perfusion(LP).Met... Background:The aim of the study was to explore a feasible method for alleviating limb ischemia-reperfusion injury(LI/RI)through the use of a high-concentration citrate solution(HC-A solution)for limb perfusion(LP).Methods:Eighteen pigs were divided into three groups:the Sham group,LI/RI group,and HCA group.The Sham group underwent exposure of the iliac artery and vein.The LI/RI group underwent tourniquet placement and clamping of the iliac artery and vein to simulate LI/RI.The HCA group received HC-A solution LP for 30 min through the left iliac artery below the level of blood flow occlusion based on the LI/RI group.Oxidative stress markers and inflammatory response markers were compared among the three groups.Results:Compared to the LI/RI group,the HCA group showed significantly lower levels of serum creatine kinase(CK),lactate dehydrogenase(LDH),malondialdehyde(MDA),tumor necrosis factor-α(TNF-α),aspartate aminotransferase(AST),and ala-nine aminotransferase(ALT),and significantly greater activities of serum superoxide dismutase(SOD)(p<0.05).There were no significant differences in serum interleukin-6(IL-6)or in muscle MDA,SOD,TNF-α,and IL-6 between the HCA group and the LI/RI group(p>0.05).Compared to the LI/RI group,MDA,TNF-α,and IL-6 levels in the liver were significantly lower in the HCA group(p<0.05),while SOD activities were not significantly different(p>0.05).Histopathological examination revealed reduced skeletal muscle and liver damage in the HCA group compared to the LI/RI group.Conclusions:HC-A solution LP can alleviate liver damage caused by LI/RI in pigs. 展开更多
关键词 HC-A solution limb ischemia-reperfusion injury limb perfusion tourniquet-related complications
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POSITIVE GROUND STATE SOLUTIONS FOR A QUASILINEAR SCHRODINGER EQUATION
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作者 JIN Qing-fei 《数学杂志》 2025年第2期95-110,共16页
This paper is concerned with the positive ground state solutions for a quasilinear Schrodinger equation with a Hardy-type term.We obtain positive ground state solutions for the given quasilinear Schrodinger equation b... This paper is concerned with the positive ground state solutions for a quasilinear Schrodinger equation with a Hardy-type term.We obtain positive ground state solutions for the given quasilinear Schrodinger equation by using a change of variables and variational method. 展开更多
关键词 Quasilinear equation schrodinger equation positive ground state solutions variational methods
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Sign-changing Solutions for a Fractional Schrödinger-Poisson System with Concave-convex Nonlinearities and a Steep Potential Well
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作者 FU Jiao LI Hongying LIAO Jiafeng 《数学理论与应用》 2025年第1期25-44,共20页
In this paper,we investigate the following fractional Schrödinger-Poisson system with concave-convex nonlinearities and a steep potential well{(-Δ)^(s)u+V_(λ)(x)u+ϕu=f(x)|u|^(q-2)u+|u|^(p-2)u,in R^(3),(-Δ)^(t)... In this paper,we investigate the following fractional Schrödinger-Poisson system with concave-convex nonlinearities and a steep potential well{(-Δ)^(s)u+V_(λ)(x)u+ϕu=f(x)|u|^(q-2)u+|u|^(p-2)u,in R^(3),(-Δ)^(t)ϕ=u^(2),in R^(3),where s∈(3/4,1),t∈(0,1),q∈(1,2),p∈(4,2_(s)^(*)),2_(s)^(*):=6/3-2s is the fractional critical exponent in dimension 3,V_(λ)(x)=λV(x)+1 withλ>0.Under the case of steep potential well,we obtain the existence of the sign-changing solutions for the above system by using the constraint variational method and the quantitative deformation lemma.Furthermore,we prove that the energy of ground state sign-changing solution is strictly more than twice of the energy of the ground state solution.Our results improve the recent results in the literature. 展开更多
关键词 Fractional Schrödinger-Poisson system Concave-convex nonlinearity Sign-changing solution Steep potential well
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Solid solution dependence of the deformation behavior in Mg-xZn(x=0,1,2 wt%)alloys:In-situ neutron diffraction and crystal plasticity modeling
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作者 Huai Wang Soo Yeol Lee +3 位作者 You Sub Kim Huamiao Wang Wanchuck Woo Ke An 《Journal of Magnesium and Alloys》 2025年第2期823-838,共16页
The effects of solid solution on the deformation behavior of binary Mg-xZn(x=0,1,2 wt%)alloys featuring a designated texture that enables extension twinning under tension parallel to the basal pole in most grains,were... The effects of solid solution on the deformation behavior of binary Mg-xZn(x=0,1,2 wt%)alloys featuring a designated texture that enables extension twinning under tension parallel to the basal pole in most grains,were investigated using in-situ neutron diffraction and the EVPSC-TDT model.Neutron diffraction was used to quantitatively track grain-level lattice strains and diffraction intensity changes(related to mechanical twinning)in differently oriented grains of each alloy during cyclic tensile/compressive loadings.These measurements were accurately captured by the model.The stress-strain curves of Mg-1 wt%Zn and Mg-2 wt%Zn alloys show as-expected solid solution strengthening from the addition of Zn compared to pure Mg.The macroscopic yielding and hardening behaviors are explained by alternating slip and twinning modes as calculated by the model.The solid solution's influence on individual deformation modes,including basal〈a〉slip,prismatic〈a〉slip,and extension twinning,was then quantitatively assessed in terms of activity,yielding behavior,and hardening response by combining neutron diffraction results with crystal plasticity predictions.The Mg-1 wt%Zn alloy displays distinct yielding and hardening behavior due to solid solution softening of prismatic〈a〉slip.Additionally,the dependence of extension twinning,in terms of the twinning volume fraction,on Zn content exhibits opposite trends under tensile and compressive loadings. 展开更多
关键词 Magnesium alloy Deformation behavior Solid solution Crystal plasticity modeling Neutron diffraction
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Multiplicity and Concentration of Positive Solutions for a Quasilinear Schrödinger-Poisson System with Critical Nonlinearity
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作者 ZHANG Weiqiang WEN Yanyun 《数学理论与应用》 2025年第1期1-24,共24页
In this paper,we study the following Schrödinger-Poisson system{-ε^(p)Δ_(p)u+V(x)|u|^(p-2)u+ϕ|u|^(p-2)u=f(u)+|u|^(p*-2)u in R^(3),-ε^(2)Δϕ=|u|^(p)in R^(3),whereε>0 is a parameter,3/2<p<3,Δ_(p)u=div... In this paper,we study the following Schrödinger-Poisson system{-ε^(p)Δ_(p)u+V(x)|u|^(p-2)u+ϕ|u|^(p-2)u=f(u)+|u|^(p*-2)u in R^(3),-ε^(2)Δϕ=|u|^(p)in R^(3),whereε>0 is a parameter,3/2<p<3,Δ_(p)u=div(|∇u|^(p-2)∇u),p^(*)=3p/3-p,V:R^(3)→R is a potential function with a local minimum and f is subcritical growth.Based on the penalization method,Nehari manifold techniques and Ljusternik-Schnirelmann category theory,we obtain the multiplicity and concentration of positive solutions to the above system. 展开更多
关键词 Schrödinger-Poisson system Positive solution Ljusternik-Schnirelmann category theory Critical growth P-LAPLACIAN
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Analytical solution for estimating the minimum required strength of sill mat by considering failure due to rock wall closure
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作者 Chuan Fan Li Li +3 位作者 Guangsheng Liu Xiaocong Yang Lijie Guo Jing Tang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第2期996-1007,共12页
Underhand cut-and-fill mining has been widely used in underground mining operations,especially when the rock mass or orebody is of poor quality or prone to rockburst due to high stress.In such cases,mining workers sho... Underhand cut-and-fill mining has been widely used in underground mining operations,especially when the rock mass or orebody is of poor quality or prone to rockburst due to high stress.In such cases,mining workers should carry out all production activities under the cemented backfill roof or sill mat instead of a highly fractured and unstable rock roof or a strong rock roof with a high potential of rockburst.Therefore,the stability and required strength of the sill mat are critical issues for mining engineers.In 1991,Mitchell considered that sill mat could fail by caving,sliding,rotation,and flexure.Mitchell also proposed an analytical solution to determine the minimum required strength of the sill mat for each type of failure based on two stiff or immobile rock walls.However,recent publications using numerical modeling and field measurements indicate that the compressive stresses in the sill mat induced by rock wall closure due to a stope excavation beneath the sill mat can be significant.It is thus highly necessary to investigate the required strength of the sill mat by considering rock wall closure.In this study,the crushing failure of sill mat due to rock wall closure generated by underground excavation and a new failure mode called"crushing and caving”is revealed by numerical modeling.An analytical solution corresponding to each failure mode is then developed to estimate the minimum required cohesion(cmin)of the sill mat.A criterion is also proposed to determine if the sill mat fails by crushing or crushing-and-caving failure.The proposed analytical solution does not involve any correction coefficients.The validity of the proposed analytical solution is demonstrated by numerical modeling.The proposed analytical solution can thus be employed to predict the cmin of sill mat subjected to wall closure generated by underlying stope excavation. 展开更多
关键词 Underhand cut-and-fill mining Cemented backfill Wall closure CRUSHING Required strength Analytical solution
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