期刊文献+
共找到10,504篇文章
< 1 2 250 >
每页显示 20 50 100
Predicted Critical State Based on Invariance of the Lyapunov Exponent in Dual Spaces
1
作者 刘通 夏旭 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第1期68-76,共9页
Critical states in disordered systems,fascinating and subtle eigenstates,have attracted a lot of research interests.However,the nature of critical states is difficult to describe quantitatively,and in general,it canno... Critical states in disordered systems,fascinating and subtle eigenstates,have attracted a lot of research interests.However,the nature of critical states is difficult to describe quantitatively,and in general,it cannot predict a system that hosts the critical state.We propose an explicit criterion whereby the Lyapunov exponent of the critical state should be 0 simultaneously in dual spaces,namely the Lyapunov exponent remains invariant under the Fourier transform.With this criterion,we can exactly predict a one-dimensional quasiperiodic model which is not of self-duality,but hosts a large number of critical states.Then,we perform numerical verification of the theoretical prediction and display the self-similarity of the critical state.Due to computational complexity,calculations are not performed for higher dimensional models.However,since the description of extended and localized states by the Lyapunov exponent is universal and dimensionless,utilizing the Lyapunov exponent of dual spaces to describe critical states should also be universal.Finally,we conjecture that some kind of connection exists between the invariance of the Lyapunov exponent and conformal invariance,which can promote the research of critical phenomena. 展开更多
关键词 STATE exponent CRITICAL
下载PDF
Application of the Conditional Nonlinear Local Lyapunov Exponent to Second-Kind Predictability
2
作者 Ming ZHANG Ruiqiang DING +2 位作者 Quanjia ZHONG Jianping LI Deyu LU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第9期1769-1786,共18页
In order to quantify the influence of external forcings on the predictability limit using observational data,the author introduced an algorithm of the conditional nonlinear local Lyapunov exponent(CNLLE)method.The eff... In order to quantify the influence of external forcings on the predictability limit using observational data,the author introduced an algorithm of the conditional nonlinear local Lyapunov exponent(CNLLE)method.The effectiveness of this algorithm is validated and compared with the nonlinear local Lyapunov exponent(NLLE)and signal-to-noise ratio methods using a coupled Lorenz model.The results show that the CNLLE method is able to capture the slow error growth constrained by external forcings,therefore,it can quantify the predictability limit induced by the external forcings.On this basis,a preliminary attempt was made to apply this method to measure the influence of ENSO on the predictability limit for both atmospheric and oceanic variable fields.The spatial distribution of the predictability limit induced by ENSO is similar to that arising from the initial conditions calculated by the NLLE method.This similarity supports ENSO as the major predictable signal for weather and climate prediction.In addition,a ratio of predictability limit(RPL)calculated by the CNLLE method to that calculated by the NLLE method was proposed.The RPL larger than 1 indicates that the external forcings can significantly benefit the long-term predictability limit.For instance,ENSO can effectively extend the predictability limit arising from the initial conditions of sea surface temperature over the tropical Indian Ocean by approximately four months,as well as the predictability limit of sea level pressure over the eastern and western Pacific Ocean.Moreover,the impact of ENSO on the geopotential height predictability limit is primarily confined to the troposphere. 展开更多
关键词 conditional nonlinear local Lyapunov exponent second-kind predictability coupled Lorenz model ENSO
下载PDF
The Dual of the Two-Variable Exponent Amalgam Spaces (Lq(),lp())(Ω)
3
作者 Sambourou Massinanke Sékou Coulibaly Mamadou Traore 《Journal of Applied Mathematics and Physics》 2024年第2期383-431,共49页
Wiener amalgam spaces are a class of function spaces where the function’s local and global behavior can be easily distinguished. These spaces are ex-tensively used in Harmonic analysis that originated in the work of ... Wiener amalgam spaces are a class of function spaces where the function’s local and global behavior can be easily distinguished. These spaces are ex-tensively used in Harmonic analysis that originated in the work of Wiener. In this paper: we first introduce a two-variable exponent amalgam space (L<sup>q</sup><sup>()</sup>,l<sup>p</sup><sup>()</sup>)(Ω). Secondly, we investigate some basic properties of these spaces, and finally, we study their dual. 展开更多
关键词 Amalgam Spaces Variable exponent Lebesgue Spaces Dual of a Vector Space
下载PDF
伪抛物型p-Kirchhoff方程的爆破解
4
作者 李锋杰 李平 《数学物理学报(A辑)》 CSCD 北大核心 2024年第3期717-736,共20页
该文研究了一类具有变指数的伪抛物型p-Kirchhoff方程的齐次Dirichlet初边值问题.首先,采用改进的势阱法和辅助函数法,对初始能量进行最优分类,得到解的爆破和整体存在的判据.其次,分别得到了解的爆破时间估计和整体解的大时间性态.
关键词 伪抛物型p-Kirchhoff方程 大时间性态 爆破时间 初始能量 变指数
下载PDF
TWO DISJOINT AND INFINITE SETS OF SOLUTIONS FOR AN ELLIPTIC EQUATION INVOLVING CRITICAL HARDY-SOBOLEV EXPONENTS
5
作者 Khalid BOUABID Rachid ECHARGHAOUI Mohssine EL MANSOUR 《Acta Mathematica Scientia》 SCIE CSCD 2023年第5期2061-2074,共14页
In this paper,by an approximating argument,we obtain two disjoint and infinite sets of solutions for the following elliptic equation with critical Hardy-Sobolev exponents■whereΩis a smooth bounded domain in RN with ... In this paper,by an approximating argument,we obtain two disjoint and infinite sets of solutions for the following elliptic equation with critical Hardy-Sobolev exponents■whereΩis a smooth bounded domain in RN with 0∈?Ωand all the principle curvatures of?Ωat 0 are negative,a∈C1(Ω,R*+),μ>0,0<s<2,1<q<2 and N>2(q+1)/(q-1).By2*:=2N/(N-2)and 2*(s):(2(N-s))/(N-2)we denote the critical Sobolev exponent and Hardy-Sobolev exponent,respectively. 展开更多
关键词 Laplacien critical Sobolev-Hardy exponent critical Sobolev exponent infinitely many solutions Pohozaev identity
下载PDF
THEORETICAL RESULTS ON THE EXISTENCE,REGULARITY AND ASYMPTOTIC STABILITY OF ENHANCED PULLBACK ATTRACTORS:APPLICATIONS TO 3D PRIMITIVE EQUATIONS
6
作者 王仁海 郭柏灵 黄代文 《Acta Mathematica Scientia》 SCIE CSCD 2023年第6期2493-2518,共26页
Several new concepts of enhanced pullback attractors for nonautonomous dynamical systems are introduced here by uniformly enhancing the compactness and attraction of the usual pullback attractors over an infinite forw... Several new concepts of enhanced pullback attractors for nonautonomous dynamical systems are introduced here by uniformly enhancing the compactness and attraction of the usual pullback attractors over an infinite forward time-interval under strong and weak topologies.Then we provide some theoretical results for the existence,regularity and asymptotic stability of these enhanced pullback attractors under general theoretical frameworks which can be applied to a large class of PDEs.The existence of these enhanced attractors is harder to obtain than the backward case[33],since it is difficult to uniformly control the long-time pullback behavior of the systems over the forward time-interval.As applications of our theoretical results,we consider the famous 3D primitive equations modelling the large-scale ocean and atmosphere dynamics,and prove the existence,regularity and asymptotic stability of the enhanced pullback attractors in V×V and H^(2)×H^(2) for the time-dependent forces which satisfy some weak conditions. 展开更多
关键词 3D primitive equations pullback attractors REGULARITY FATTENING stability
下载PDF
Gradient descent decomposition of force-field motor primitives optogenetically elicited for motor mapping of the murine lumbosacral spinal cord
7
作者 Paola Salmas Vincent C.K Cheung 《Zoological Research》 SCIE CAS CSCD 2023年第3期604-619,共16页
Generating diverse motor behaviors critical for survival is a challenge that confronts the central nervous system(CNS)of all animals.During movement execution,the CNS performs complex calculations to control a large n... Generating diverse motor behaviors critical for survival is a challenge that confronts the central nervous system(CNS)of all animals.During movement execution,the CNS performs complex calculations to control a large number of neuromusculoskeletal elements.The theory of modular motor control proposes that spinal interneurons are organized in discrete modules that can be linearly combined to generate a variety of behavioral patterns.These modules have been previously represented as stimulus-evoked force fields(FFs)comprising isometric limb-endpoint forces across workspace locations.Here,we ask whether FFs elicited by different stimulations indeed represent the most elementary units of motor control or are themselves the combination of a limited number of even more fundamental motor modules.To probe for potentially more elementary modules,we optogenetically stimulated the lumbosacral spinal cord of intact and spinalized Thy1-ChR2 transgenic mice(n=21),eliciting FFs from as many single stimulation loci as possible(20-70 loci per mouse)at minimally necessary power.We found that the resulting varieties of FFs defied simple categorization with just a few clusters.We used gradient descent to further decompose the FFs into their underlying basic force fields(BFFs),whose linear combination explained FF variability.Across mice,we identified 4-5 BFFs with partially localizable but overlapping representations along the spinal cord.The BFFs were structured and topographically distributed in such a way that a rostral-to-caudal traveling wave of activity across the lumbosacral spinal cord may generate a swing-to-stance gait cycle.These BFFs may represent more rudimentary submodules that can be flexibly merged to produce a library of motor modules for building different motor behaviors. 展开更多
关键词 Motor mapping OPTOGENETICS Spinal cord Motor primitives Traveling wave
下载PDF
The regulation of ferrocene-based catalysts on heat transfer in highpressure combustion of ammonium perchlorate/hydroxyl-terminated polybutadiene/aluminum composite propellants 被引量:1
8
作者 Jinchao Han Songqi Hu Linlin Liu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第5期174-186,共13页
The regulation of the burning rate pressure exponent for the ammonium perchlorate/hydroxylterminated polybutadiene/aluminum(AP/HTPB/Al)composite propellants under high pressures is a crucial step for its application i... The regulation of the burning rate pressure exponent for the ammonium perchlorate/hydroxylterminated polybutadiene/aluminum(AP/HTPB/Al)composite propellants under high pressures is a crucial step for its application in high-pressure solid rocket motors.In this work,the combustion characteristics of AP/HTPB/Al composite propellants containing ferrocene-based catalysts were investigated,including the burning rate,thermal behavior,the local heat transfer,and temperature profile in the range of 7-28 MPa.The results showed that the exponent breaks were still observed in the propellants after the addition of positive catalysts(Ce-Fc-MOF),the burning rate inhibitor((Ferrocenylmethyl)trimethylammonium bromide,Fc Br)and the mixture of Fc Br/catocene(GFP).However,the characteristic pressure has increased,and the exponent decreased from 1.14 to 0.66,0.55,and 0.48 when the addition of Ce-FcMOF,Fc Br and Fc Br/GFP in the propellants.In addition,the temperature in the first decomposition stage was increased by 7.50℃ and 11.40℃ for the AP/Fc Br mixture and the AP/Fc Br/GFP mixture,respectively,compared to the pure AP.On the other hand,the temperature in the second decomposition stage decreased by 48.30℃ and 81.70℃ for AP/Fc Br and AP/Fc Br/GFP mixtures,respectively.It was also found that Fc Br might generate ammonia to cover the AP surface.In this case,a reaction between the methyl in Fc Br and perchloric acid caused more ammonia to appear at the AP surface,resulting in the suppression of ammonia desorption.In addition,the coarse AP particles on the quenched surface were of a concave shape relative to the binder matrix under low and high pressures when the catalysts were added.In the process,the decline at the AP/HTPB interface was only exhibited in the propellant with the addition of Ce-Fc-MOF.The ratio of the gas-phase temperature gradient of the propellants containing catalysts was reduced significantly below and above the characteristic pressure,rather than 3.6 times of the difference in the blank propellant.Overall,the obtained results demonstrated that the pressure exponent could be effectively regulated and controlled by adjusting the propellant local heat and mass transfer under high and low pressures. 展开更多
关键词 AP/HTPB/Al propellants Heat transfer High-pressure combustion Ferrocene-based catalysts Pressure exponent
下载PDF
General mapping of one-dimensional non-Hermitian mosaic models to non-mosaic counterparts:Mobility edges and Lyapunov exponents
9
作者 蒋盛莲 刘彦霞 郎利君 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期79-86,共8页
We establish a general mapping from one-dimensional non-Hermitian mosaic models to their non-mosaic counterparts.This mapping can give rise to mobility edges and even Lyapunov exponents in the mosaic models if critica... We establish a general mapping from one-dimensional non-Hermitian mosaic models to their non-mosaic counterparts.This mapping can give rise to mobility edges and even Lyapunov exponents in the mosaic models if critical points of localization or Lyapunov exponents of localized states in the corresponding non-mosaic models have already been analytically solved.To demonstrate the validity of this mapping,we apply it to two non-Hermitian localization models:an Aubry-Andre-like model with nonreciprocal hopping and complex quasiperiodic potentials,and the Ganeshan-Pixley-Das Sarma model with nonreciprocal hopping.We successfully obtain the mobility edges and Lyapunov exponents in their mosaic models.This general mapping may catalyze further studies on mobility edges,Lyapunov exponents,and other significant quantities pertaining to localization in non-Hermitian mosaic models. 展开更多
关键词 non-Hermitian mosaic model mosaic-to-non-mosaic mapping mobility edge Lyapunov exponent
下载PDF
带临界指数的Kirchhoff型线性耦合方程组正解的多重性
10
作者 段雪亮 吴晓凡 +1 位作者 魏公明 杨海涛 《数学物理学报(A辑)》 CSCD 北大核心 2024年第3期699-716,共18页
该文研究了如下带Sobolev临界指数的Kirchhoff型线性耦合方程组{−(1+b_(1)∥u∥^(2))Δu+λ_(1)u=u5+βv,x∈Ω,−(1+b_(2)∥v∥^(2))Δv+λ_(2)v=v^(5)+βu,x∈Ω,u=v=0在∂Ω上,其中Ω⊂R^(3)是一个开球,∥⋅∥表示H_(0)^(1)(Ω)的范数,β... 该文研究了如下带Sobolev临界指数的Kirchhoff型线性耦合方程组{−(1+b_(1)∥u∥^(2))Δu+λ_(1)u=u5+βv,x∈Ω,−(1+b_(2)∥v∥^(2))Δv+λ_(2)v=v^(5)+βu,x∈Ω,u=v=0在∂Ω上,其中Ω⊂R^(3)是一个开球,∥⋅∥表示H_(0)^(1)(Ω)的范数,β∈R是一个耦合参数.常数b_(i)≥0和λ_(i)∈(−λ_(1)(Ω),−1/4λ_(1)(Ω)),i=1,2,这里λ_(1)(Ω)是(−Δ,H_(0)^(1)(Ω))的第一特征值.在含有Kirchhoff项的情形下,利用变分法证明了方程组有一个正基态解和一个高能量的正解,并研究了当β→0时这两个解的渐近行为. 展开更多
关键词 KIRCHHofF 型方程 线性耦合方程组 SOBOLEV 临界指数 变分法
下载PDF
The κ-point Exponent Set of Central Symmetric Primitive Matrices
11
作者 陈余喜 《Northeastern Mathematical Journal》 CSCD 2007年第2期132-140,共9页
Let G =(Y, E) be a primitive digraph. The vertex exponent of G at a vertex v E V, denoted by expG(v), is the least integer p such that there is a v → u walk of length p for each u E V. We choose to order the vert... Let G =(Y, E) be a primitive digraph. The vertex exponent of G at a vertex v E V, denoted by expG(v), is the least integer p such that there is a v → u walk of length p for each u E V. We choose to order the vertices of G in such a way that expG(v1) ≤ expG(v2) ≤... ≤expG(vn). Then expG(vk) is called the k-point exponent of G and is denoted by expG(k), 1 〈 k 〈 n. We define the k-point exponent set E(n, k) := {expG(k)|G= G(A) with A E CSP(n)|, where CSP(n) is the set of all n × n central symmetric primitive matrices and G(A) is the associated graph of the matrix A. In this paper, we describe E(n, k) for all n, k with 1 〈 k 〈 n except n ≡ l(mod 2) and 1 〈 k 〈 n - 4. We also characterize the extremal graphs when k = 1. 展开更多
关键词 exponent symmetric primitive matrix associated graph
下载PDF
The Exponent Set of Central Symmetric Primitive Matrices
12
作者 陈佘喜 胡亚辉 《Northeastern Mathematical Journal》 CSCD 2004年第4期424-434,共11页
This paper first establishes a distance inequality of the associated dia-graph of a central symmetric primitive matrix, then characters the exponent set of central symmetric primitive matrices, and proves that the exp... This paper first establishes a distance inequality of the associated dia-graph of a central symmetric primitive matrix, then characters the exponent set of central symmetric primitive matrices, and proves that the exponent set of central symmetric primitive matrices of order n is {1, 2,…, n - 1}. There is no gap in it. 展开更多
关键词 exponent primitive matrix primitive symmetric diagraph shortest path
下载PDF
Influence of temperature, stress, and grain size on behavior of nano-polycrystalline niobium
13
作者 晏玉平 张柳亭 +2 位作者 张丽攀 芦刚 涂志新 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期467-474,共8页
Atomic simulations are executed to investigate the creep responses of nano-polycrystalline(NC) niobium established by using the Voronoi algorithm. The effects of varying temperature, applied stress, and grain size(GS)... Atomic simulations are executed to investigate the creep responses of nano-polycrystalline(NC) niobium established by using the Voronoi algorithm. The effects of varying temperature, applied stress, and grain size(GS) on creep properties and mechanisms are investigated. Notably, the occurrence of tertiary creep is exclusively observed under conditions where the applied stress exceeds 4.5 GPa and the temperature is higher than 1100 K. This phenomenon can be attributed to the significant acceleration of grain boundary and lattice diffusion, driven by the elevated temperature and stress levels. It is found that the strain rate increases with both temperature and stress increasing. However, an interesting trend is observed in which the strain rate decreases as the grain size increases. The stress and temperature are crucial parameters governing the creep behavior. As these factors intensify, the creep mechanism undergoes a sequential transformation: initially from lattice diffusion under low stress and temperature conditions to a mixed mode combining grain boundaries(GBs) and lattice diffusion at moderate stress and mid temperature levels, and ultimately leading to the failure of power-law controlled creep behavior, inclusive of grain boundary recrystallization under high stress and temperature conditions. This comprehensive analysis provides in more detail an understanding of the intricate creep behavior of nano-polycrystalline niobium and its dependence on various physical parameters. 展开更多
关键词 creep behavior molecular dynamics simulation activation energy stress exponent nano-polycrystalline niobium
下载PDF
The Predictability Limit of Oceanic Mesoscale Eddy Tracks in the South China Sea
14
作者 Hailong LIU Pingxiang CHU +5 位作者 Yao MENG Mengrong DING Pengfei LIN Ruiqiang DING Pengfei WANG Weipeng ZHENG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第9期1661-1679,共19页
Employing the nonlinear local Lyapunov exponent (NLLE) technique, this study assesses the quantitative predictability limit of oceanic mesoscale eddy (OME) tracks utilizing three eddy datasets for both annual and seas... Employing the nonlinear local Lyapunov exponent (NLLE) technique, this study assesses the quantitative predictability limit of oceanic mesoscale eddy (OME) tracks utilizing three eddy datasets for both annual and seasonal means. Our findings reveal a discernible predictability limit of approximately 39 days for cyclonic eddies (CEs) and 44 days for anticyclonic eddies (AEs) within the South China Sea (SCS). The predictability limit is related to the OME properties and seasons. The long-lived, large-amplitude, and large-radius OMEs tend to have a higher predictability limit. The predictability limit of AE (CE) tracks is highest in autumn (winter) with 52 (53) days and lowest in spring (summer) with 40 (30) days. The spatial distribution of the predictability limit of OME tracks also has seasonal variations, further finding that the area of higher predictability limits often overlaps with periodic OMEs. Additionally, the predictability limit of periodic OME tracks is about 49 days for both CEs and AEs, which is 5-10 days higher than the mean values. Usually, in the SCS, OMEs characterized by high predictability limit values exhibit more extended and smoother trajectories and often move along the northern slope of the SCS. 展开更多
关键词 PREDICTABILITY mesoscale eddy nonlinear local Lyapunov exponent South China Sea seasonal variability
下载PDF
Existence of Entropy Solution for Degenerate Parabolic-Hyperbolic Problem Involving p(x)-Laplacian with Neumann Boundary Condition
15
作者 Mohamed Karimou Gazibo Duni Yegbonoma Frédéric Zongo 《Applied Mathematics》 2024年第7期455-463,共9页
We consider a strongly non-linear degenerate parabolic-hyperbolic problem with p(x)-Laplacian diffusion flux function. We propose an entropy formulation and prove the existence of an entropy solution.
关键词 Lebesgue and Sobolev Spaces with Variable exponent Weak Solution Entropy Solution Degenerate Parabolic-Hyperbolic Equation Conservation Law Leray Lions Type Operator Neumann Boundary Condition Existence Result
下载PDF
From Witch’s Ritual Performance to Writer’s Creation of Text—On Discussing How to“Treat Oneself”and“Cure Others”About Literature’s Function
16
作者 GONG Wei-jun XU Yue 《Cultural and Religious Studies》 2024年第7期417-427,共11页
In the post-modernistic movement to seek for the cultural root,literary anthropologists refocus and explore the original therapeutic function of literature,and make great efforts to restore the essence of disciplines... In the post-modernistic movement to seek for the cultural root,literary anthropologists refocus and explore the original therapeutic function of literature,and make great efforts to restore the essence of disciplines’theory that“literature is human science”to the real context of cultural integration.Based on this,the article intends to treat witch’s great traditional ritual as a starting point,aiming at building up and enriching the ethnography of literary therapy.However,in order to change roles from witches to writers and promote the primitive return of literary therapy,writers make little traditional creation of text focus on interpretation of“treating themselves”and“curing others”about literature’s function. 展开更多
关键词 literary therapy Great Tradition ETHNOGRAPHY primitive return
下载PDF
The Black Protests in Poland: An Example of an Anti-pastoral Revolution
17
作者 Szymon Wróbel 《Philosophy Study》 2024年第2期53-62,共10页
Michel Foucault in Security, Territory, Population: Lectures at the Collège de France, 1977-1978 argues, that there has never been such a thing as an anti-pastoral revolution in Western societies. Yes, we have ha... Michel Foucault in Security, Territory, Population: Lectures at the Collège de France, 1977-1978 argues, that there has never been such a thing as an anti-pastoral revolution in Western societies. Yes, we have had revolutions against the disciplinary apparatus and legal devices of power (schools, hospitals, prisons) and we have had examples of revolutions against the economic foundations of social inequality, but there has never been a genuine revolution against pastoral power as a power relating to the conduct of individuals (but also entire social groups) and their disposition to “voluntary submission” to the will of external authorities. In my paper, I would like to reflect on this thesis, and taking it quite seriously, to look for examples of such revolutions. One of them is a women’s strike in Poland during the power of the conservative government of “Law and Justice”. Mainly referring to the texts of Silvia Federici and Paul Preciado, I will want to reflect on contemporary practices of reclaiming the body in contemporary capitalism. I will defend the thesis that regaining control over sexuality and reproduction means changing the material conditions of life and modern reproductive technologies. 展开更多
关键词 black protest morning-after pill primitive accumulation procreation refusal resistance voluntary submission women’s reproductive strike
下载PDF
具有临界增长的分数阶Choquard-Kirchhoff型问题解的存在性
18
作者 桑彦彬 车银芳 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第5期1-7,共7页
本文研究一类无界区域上分数阶Choquard-Kirchhoff型问题,此类问题源于横振动中对弦长的非局部测量引起的张力,也可用于刻画量子机械波函数的自引力坍缩.该方程的非线性项包含临界项μ(I_(a)^(*)|u|^(2_(a,s)^(*)-2)u|)和扰动项λf(x)uq... 本文研究一类无界区域上分数阶Choquard-Kirchhoff型问题,此类问题源于横振动中对弦长的非局部测量引起的张力,也可用于刻画量子机械波函数的自引力坍缩.该方程的非线性项包含临界项μ(I_(a)^(*)|u|^(2_(a,s)^(*)-2)u|)和扰动项λf(x)uq-1,其中μ,λ均为正参数,2^(*)_(a,s)为分数阶Hardy-Littlewood-Sobolev临界指数,f(x)为连续函数.本文首先利用Nehari流形及Ekeland变分原理证得问题对应的能量泛函具有Palais-Smale序列,然后对参数μ的上界进行估计,在参数λ和次数q选取适当范围时借助Vitali定理及山路引理获得了问题正解的存在性及多重性.最后,当参数λ充分大时,本文利用强极大值原理及临界点定理建立了问题具有正解及无穷多对不同解的存在性定理. 展开更多
关键词 分数阶Choquard-Kirchhoff型问题 Hardy-Littlewood-Sobolev临界指数 NEHARI流形
下载PDF
Appropriate Garden Design of Primitive Ecology Based on the Indigenization of Environmental Ethics 被引量:1
19
作者 章晓岗 王长富 《Journal of Landscape Research》 2010年第2期29-32,95,共5页
The accelerating urbanization process leads to aggravated environmental problems, thus garden design which is a creative activity connecting human and nature has attracted much attention, and also garden designers hav... The accelerating urbanization process leads to aggravated environmental problems, thus garden design which is a creative activity connecting human and nature has attracted much attention, and also garden designers have had to rethink about environmental ethics and morals. This study, from the perspective of environmental ethics, duly proposed the brand-new concept of 'appropriate garden of primitive ecology', proceeded from the orientation, form, value, theoretical basis, realistic significance, culture and consumption psychology of 'garden of primitive ecology', fully developed outstanding ecological wisdoms and morals in traditional Chinese garden culture, boosted garden designs to the environmental ethics level of eco-justice, to seek for the approach to 'garden of primitive ecology' with indigenous Chinese environmental ethic characteristics. 展开更多
关键词 Environmental ethics Garden of primitive ecology Appropriate design INDIGENIZATION Eco-justice
下载PDF
CALCULATION OF CRITICAL EXPONENT β(L) OF MAGNETIC THIN FILMS BY USING ISING MODEL
20
作者 霍炳海 区镜添 《Transactions of Tianjin University》 EI CAS 1998年第2期51-54,共4页
The variational cumulant expansion developed in recent years has been extended to treat the Ising model in statistical physics.In this paper,a detailed calculation of the critical temperature T c (L) and criti... The variational cumulant expansion developed in recent years has been extended to treat the Ising model in statistical physics.In this paper,a detailed calculation of the critical temperature T c (L) and critical exponent β(L) for the magnetic film of L layers are presented by means of the variational cumulant expansion.For L >1,the results of our theoretical calculations are in approximate coincidence with the experimental ones made before,and for the special case of L =1 (2 D),the results of the calculation are identical to the data from other reports. 展开更多
关键词 variational cumulant expansion critical temperature critical exponent
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部