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识字卡片在语文教学中的优势
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作者 杨玉莲 《甘肃教育》 2020年第8期143-143,共1页
识字教学是小学语文基础教育课程中最重要的内容,随着部编教材的推行使用,汉字的识记方法、字源的探究了解也成为了识字教学中必不可少的内容,汉字素养的渗透也越来越得到教师们的重视。在多媒体教学日益普及的当下,传统的识字卡片教学... 识字教学是小学语文基础教育课程中最重要的内容,随着部编教材的推行使用,汉字的识记方法、字源的探究了解也成为了识字教学中必不可少的内容,汉字素养的渗透也越来越得到教师们的重视。在多媒体教学日益普及的当下,传统的识字卡片教学方式渐渐淡化,而单借助多媒体开展识字教学也有一定的局限性。因此,在多媒体教学的运用中巧妙使用识字卡片,不但能激发学生学习汉字的兴趣和热情,而且能帮助学生形成较好的汉字应用能力。 展开更多
关键词 小学语文 识字卡片 “问题点” “兴趣点” “巩固点”
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The influencing factors and Development Countermeasures of Large Farming Household in Jiangxi Province
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作者 戴天放 麻福芳 《Agricultural Science & Technology》 CAS 2015年第3期573-577,共5页
As an important part of the new agricultural business entities, large-scale grain-production households play a significantly positive role in improving the land resource utilization, improving agricultural productivit... As an important part of the new agricultural business entities, large-scale grain-production households play a significantly positive role in improving the land resource utilization, improving agricultural productivity, increasing agricultural output and farmers" income, and making a certain contribution to stabilize grain production. This paper analyzed the current situation of large-scale grain-production household in Jiangxi Province, as well as the problems in land transfer, farmland infrastructure, production and management, capital and other risks. At last, the paper proposed targeted countermeasures. 展开更多
关键词 Large farming household Development characteristics PROBLEMS COUNTERMEASURES
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Statistical segmentation model on lattices
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作者 俞璐 谢钧 吴乐南 《Journal of Southeast University(English Edition)》 EI CAS 2008年第1期10-14,共5页
To reduce the difficulty of implementation and shorten the runtime of the traditional Kim-Fisher model, an entirely discrete Kim-Fisher-like model on lattices is proposed. The discrete model is directly built on the l... To reduce the difficulty of implementation and shorten the runtime of the traditional Kim-Fisher model, an entirely discrete Kim-Fisher-like model on lattices is proposed. The discrete model is directly built on the lattices, and the greedy algorithm is used in the implementation to continually decrease the energy function. First, regarding the gray values in images as discrete-valued random variables makes it possible to make a much simpler estimation of conditional entropy. Secondly, a uniform method within the level set framework for two-phase and multiphase segmentations without extension is presented. Finally, a more accurate approximation to the curve length on lattices with multi-labels is proposed. The experimental results show that, compared with the continuous Kim-Fisher model, the proposed model can obtain comparative results, while the implementation is much simpler and the runtime is dramatically reduced. 展开更多
关键词 image segmentation curve evolution conditional entropy LATTICE labelling problem
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Singular Perturbation of Two Points Boundary Value Problems for a Class of Third Order Quasilinear Differential Equations 被引量:1
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作者 谢峰 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第3期69-74,共6页
In this paper, the fixed-point Theorem i s used to estimate an asymptotic solution of boundary value problems for a class o f third order quasilinear differential equation and the uniformly valid asymptot ic expansio... In this paper, the fixed-point Theorem i s used to estimate an asymptotic solution of boundary value problems for a class o f third order quasilinear differential equation and the uniformly valid asymptot ic expansion of solution of any orders including boundary layer is obtained. 展开更多
关键词 fixed-point Theorem quasilinear differential eq uation asymptotic expansion singular perturbaiton
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Positive Solutions of a Semilinear Elliptic Equation with Coefficient That Changes Sign
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作者 马如云 姚庆六 李宝麟 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第4期10-14,共5页
We prove the existence of a positive solution to the problem-Δu=a(x)f(u), x∈Ω, u(x)=0,x∈Ω,where Ω is a bounded domain in R n with smooth boundary, a(x) is allowed to change sign.
关键词 elliptic equation positive solution Leray-Schauder fixed point theorem
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Boundary Value Problems of p-Laplace Equations with Finite Time Delay
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作者 王宏洲 邓立虎 葛渭高 《Journal of Beijing Institute of Technology》 EI CAS 2001年第1期1-6,共6页
By establishing equivalent fixed point theorem, the boundary value problems of p Laplace equations with finite time delay are studied. It’s the first time that the functional differential equation is discussed w... By establishing equivalent fixed point theorem, the boundary value problems of p Laplace equations with finite time delay are studied. It’s the first time that the functional differential equation is discussed with p Laplacian. The topological degree and fixed point theorem on cone are used to prove the existence of solution and positive solution. The conditions are all easy to check. 展开更多
关键词 boundary value problem n Laplacian finite time delay fixed point
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Existence of Solutions for S-L Singular Boundary Value Problems with p-Laplacian Operators
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作者 郭彦平 葛渭高 单文锐 《Journal of Beijing Institute of Technology》 EI CAS 2002年第2期220-224,共5页
The existence of solutions for singular nonlinear two point boundary value problems subject to Sturm Liouville boundary conditions with p Laplacian operators is studied by the method of upper and lower solution... The existence of solutions for singular nonlinear two point boundary value problems subject to Sturm Liouville boundary conditions with p Laplacian operators is studied by the method of upper and lower solutions. The proof is based on an application of Schauder’s fixed point theorem to a modified problem whose solutions are that of the original one. At the same time, Arzela Ascoli theorem is used to prove that the defined operator N is a compact map. 展开更多
关键词 nonlinear boundary value problems p Laplacian operators fixed point upper solution lower solution
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Singular Solutions of the Cauchy Problem for SemilinearParabolic Equations with Singular Potentions
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作者 曾有栋 陈祖墀 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第1期1-8,共8页
In this paper we consider the Cauchy problem for the singular semilinear parabolic equation u t-Δu+V 1(x)u=V 2(x)u p,x∈R n\{0},t>0, where V 1(x),V 2(x) may have singularities at the origin. Using functions... In this paper we consider the Cauchy problem for the singular semilinear parabolic equation u t-Δu+V 1(x)u=V 2(x)u p,x∈R n\{0},t>0, where V 1(x),V 2(x) may have singularities at the origin. Using functions of the Kato class and the Green tight functions we got the existence of the positive solution being singular at the origin. 展开更多
关键词 SINGULARITY Kato class Green tight function fixed point
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L(d,1)-labeling of regular tilings
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作者 戴本球 宋增民 《Journal of Southeast University(English Edition)》 EI CAS 2005年第1期115-118,共4页
L(d, 1)-labeling is a kind of graph coloring problem from frequency assignment in radio networks, in which adjacent nodes must receive colors that are at least d apart while nodes at distance two from each other must ... L(d, 1)-labeling is a kind of graph coloring problem from frequency assignment in radio networks, in which adjacent nodes must receive colors that are at least d apart while nodes at distance two from each other must receive different colors. We focus on L(d, 1)-labeling of regular tilings for d≥3 since the cases d=0, 1 or 2 have been researched by Calamoneri and Petreschi. For all three kinds of regular tilings, we give their L (d, 1)-labeling numbers for any integer d≥3. Therefore, combined with the results given by Calamoneri and Petreschi, the L(d, 1)-labeling numbers of regular tilings for any nonnegative integer d may be determined completely. 展开更多
关键词 Graph theory Radio communication
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Positive Solutions of Boundary Value Problems for Systems of Nonlinear Second-order Differential Equations 被引量:3
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作者 ZHENG Dong-mei LU Shi-ping 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第2期179-184,共6页
By using fixed-point index theory,we study boundary value problems for systems of nonlinear second-order differential equation,and a result on existence and multiplicity of positive solutions is obtained.
关键词 boundary value problems fixed-point index positive solution CONE
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On the Existence of Positive Solutions of Singular Second Order Boundary Value Problems 被引量:2
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作者 LIHe-cheng 《Chinese Quarterly Journal of Mathematics》 CSCD 2004年第1期101-106,共6页
This paper deals with the existence of positive solutions of the equation u'+f(t, u)=0 with linear boundary conditions. We show the existence of at least one positive solution if / is neither superlinear nor subli... This paper deals with the existence of positive solutions of the equation u'+f(t, u)=0 with linear boundary conditions. We show the existence of at least one positive solution if / is neither superlinear nor sublinear on u by a simple application of a fixed point Theorem in cones. 展开更多
关键词 boundary value problem positive soulution fixed point EXISTENCE
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The Existence of Solutions of Three-point Boundary Value Problems for Second Order Impulsive Differential Equation 被引量:5
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作者 CAI Guo-lan ZHANG Jian-ping GE Wei-gao 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2005年第3期247-257,共11页
We study the existence of solutions to the second order three-point boundary value problem:{x″(t)+f(t,x(t),x′(t))=0,t≠ti,△x(ti)=Ii(x(ti),x′(ti)),i=1,2,…,k,△x′(ti)=Ji(x(ti),x′(t)),i=1... We study the existence of solutions to the second order three-point boundary value problem:{x″(t)+f(t,x(t),x′(t))=0,t≠ti,△x(ti)=Ii(x(ti),x′(ti)),i=1,2,…,k,△x′(ti)=Ji(x(ti),x′(t)),i=1,2,…,k,x(0)=0=x(1)-αx(η),where 0〈η〈1,α∈R,and f:[0,1]×R×R→R,Ii:R×R→R,Ji:R×R→R(i=1,2,…,k)are continuous. Our results is new and different from previous results. In particular, we obtain the Green function of the problem, which makes the problem simpler. 展开更多
关键词 impulsive differential equation boundary value problem fixed points CONE
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A Boundary Value Problem for Second Order Functional Differential Equations with Impulses
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作者 何智敏 葛渭高 《Journal of Beijing Institute of Technology》 EI CAS 1998年第4期323-329,共7页
Aim To investigate the boundary value problem for second order functional differentiai equations with impulses. Methods The fixed point principle was used to establish our results. Results and Conclusion The results o... Aim To investigate the boundary value problem for second order functional differentiai equations with impulses. Methods The fixed point principle was used to establish our results. Results and Conclusion The results of the esistence, the uniqueness and the continuous dependence on aprameter of soiutions of the boundary value problems for second order functional differential equations with impulses are obtained. 展开更多
关键词 functional differential equation boundary value Problem impulse fixed point principle
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An Existence Theorem of Positive Solution for Fourth-order Superlinear Semipositone Eigenvalue Problems
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作者 江秀芬 姚庆六 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第2期64-68,共5页
In this paper we investigate the existence of positive solution for a class of fourth_order superlinear semipositone eigenvalue problems. This class of problems usually describes the deformation of the elastic beam wh... In this paper we investigate the existence of positive solution for a class of fourth_order superlinear semipositone eigenvalue problems. This class of problems usually describes the deformation of the elastic beam whose both end_points are fixed. 展开更多
关键词 elastic beam equation existence of positive solution SEMIPOSITONE fixed point theorem on cone
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A Parameter-Uniform Finite Difference Method for a Coupled System of Convection-Diffusion Two-Point Boundary Value Problems 被引量:3
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作者 Eugene O'Riordan Jeanne Stynes Martin Stynes 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE 2008年第2期176-197,共22页
A system of m (≥2) linear convection-diffusion two-point boundary value problems is examined,where the diffusion term in each equation is multiplied by a small parameterεand the equations are coupled through their c... A system of m (≥2) linear convection-diffusion two-point boundary value problems is examined,where the diffusion term in each equation is multiplied by a small parameterεand the equations are coupled through their convective and reactive terms via matrices B and A respectively.This system is in general singularly perturbed. Unlike the case of a single equation,it does not satisfy a conventional maximum princi- ple.Certain hypotheses are placed on the coupling matrices B and A that ensure exis- tence and uniqueness of a solution to the system and also permit boundary layers in the components of this solution at only one endpoint of the domain;these hypotheses can be regarded as a strong form of diagonal dominance of B.This solution is decomposed into a sum of regular and layer components.Bounds are established on these compo- nents and their derivatives to show explicitly their dependence on the small parameterε.Finally,numerical methods consisting of upwinding on piecewise-uniform Shishkin meshes are proved to yield numerical solutions that are essentially first-order conver- gent,uniformly inε,to the true solution in the discrete maximum norm.Numerical results on Shishkin meshes are presented to support these theoretical bounds. 展开更多
关键词 Singularly perturbed CONVECTION-DIFFUSION coupled system piecewise-uniform mesh
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Application of GA, PSO, and ACO Algorithms to Path Planning of Autonomous Underwater Vehicles 被引量:8
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作者 Mohammad Pourmahmood Aghababa Mohammad Hossein Amrollahi Mehdi Borjkhani 《Journal of Marine Science and Application》 2012年第3期378-386,共9页
In this paper, an underwater vehicle was modeled with six dimensional nonlinear equations of motion, controlled by DC motors in all degrees of freedom. Near-optimal trajectories in an energetic environment for underwa... In this paper, an underwater vehicle was modeled with six dimensional nonlinear equations of motion, controlled by DC motors in all degrees of freedom. Near-optimal trajectories in an energetic environment for underwater vehicles were computed using a nnmerical solution of a nonlinear optimal control problem (NOCP). An energy performance index as a cost function, which should be minimized, was defmed. The resulting problem was a two-point boundary value problem (TPBVP). A genetic algorithm (GA), particle swarm optimization (PSO), and ant colony optimization (ACO) algorithms were applied to solve the resulting TPBVP. Applying an Euler-Lagrange equation to the NOCP, a conjugate gradient penalty method was also adopted to solve the TPBVP. The problem of energetic environments, involving some energy sources, was discussed. Some near-optimal paths were found using a GA, PSO, and ACO algorithms. Finally, the problem of collision avoidance in an energetic environment was also taken into account. 展开更多
关键词 path planning autonomous underwater vehicle genetic algorithm (GA) particle swarmoptimization (PSO) ant colony optimization (ACO) collision avoidance
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Investigation of a Network Failure Problem with a Significant Path, from the Perspective of Crisis Management 被引量:1
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作者 Jun-ichi Takeshita Hiroaki Mohri 《Journal of Mathematics and System Science》 2014年第7期479-485,共7页
The objective of this study is to investigate a network failure problem with a significant path, emerging from the context of crisis management, such as in the case of natural disasters. For a given tree with m failed... The objective of this study is to investigate a network failure problem with a significant path, emerging from the context of crisis management, such as in the case of natural disasters. For a given tree with m failed edges, we assume that we have sufficient resources to recover k edges of the m edges. Each node has a positive weight. In this situation, we consider which k edges should be fixed in order to maximize the sum of the weights of the nodes reachable from the significant path. In this paper, we formulate such a problem as a combinatorial problem. Further, we show that a part of our problem may be solved by translating it into the terms of the so-called tree knapsack problem. 展开更多
关键词 Network failure GRAPH tree structure combinatorial optimization risk management
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Existence and Uniqueness of Solutions for Higher Order Nonlinear Multi-point Boundary Value Problems 被引量:7
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作者 PEI Ming-he Sung-Kag Chang 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第2期258-266,共9页
In this paper, the existence and uniqueness theorems of solutions of k-point boundary value problems for nth-order nonlinear differential equations are established by Leray-Schauder continuation theorem.
关键词 nth-order nonlinear differential equations k-point boundary value problem EXISTENCE UNIQUENESS
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An Existence Theorem of Solution for a Singular Third-order Two-point Boundary Value Problem 被引量:1
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作者 姚庆六 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第1期61-66,共6页
By constructing suitable Banach space, an existence theorem is established under a condition of linear growth for the third-order boundary value problem u″′(t)+f(t,u(t),u′(t))=0,0〈t〈1,u(0)=u′(0)=u′... By constructing suitable Banach space, an existence theorem is established under a condition of linear growth for the third-order boundary value problem u″′(t)+f(t,u(t),u′(t))=0,0〈t〈1,u(0)=u′(0)=u′(1)=0, where the nonlinear term contains first and second derivatives of unknown function. In this theorem the nonlinear term f(t, u, v, w) may be singular at t = 0 and t = 1. The main ingredient is Leray-Schauder nonlinear alternative. 展开更多
关键词 singular ordinary differential equation boundary value problem existence theorem nonlinear alternative
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A mixed stochastic user equilibrium model considering influence of advanced traveller information systems in degradable transport network 被引量:4
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作者 程琳 楼小明 +1 位作者 周静 马捷 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第5期1182-1194,共13页
Advanced traveler information systems (ATIS) can not only improve drivers' accessibility to the more accurate route travel time information, but also can improve drivers' adaptability to the stochastic network cap... Advanced traveler information systems (ATIS) can not only improve drivers' accessibility to the more accurate route travel time information, but also can improve drivers' adaptability to the stochastic network capacity degradations. In this paper, a mixed stochastic user equilibrium model was proposed to describe the interactive route choice behaviors between ATIS equipped and unequipped drivers on a degradable transport network. In the proposed model the information accessibility of equipped drivers was reflected by lower degree of uncertainty in their stochastic equilibrium flow distributions, and their behavioral adaptability was captured by multiple equilibrium behaviors over the stochastic network state set. The mixed equilibrium model was formulated as a fixed point problem defined in the mixed route flows, and its solution was achieved by executing an iterative algorithm. Numerical experiments were provided to verify the properties of the mixed network equilibrium model and the efficiency of the iterative algorithm. 展开更多
关键词 mixed stochastic user equilibrium model degradable transport network advanced traveler information systems (ATIS) drivers' behavioral adaptability multiple equilibrium behaviors fixed point problem
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