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Construction of Legal System of China's Farmland Protection under the Coexistence of Multiple Objectives:Historical Logic,Practical Problems and Optimization Paths
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作者 Shengnan MA Jiaxin ZHOU Yongfang YANG 《Asian Agricultural Research》 2023年第2期26-34,38,共10页
[Objectives]To explore the evolution of the legal system of farmland protection and explore the rules and characteristics of policy development based on the theory and logic of institutional change since China's r... [Objectives]To explore the evolution of the legal system of farmland protection and explore the rules and characteristics of policy development based on the theory and logic of institutional change since China's reform and opening up,reveal the problems and deep-seated reasons of its legislation,clarify the direction of farmland protection in the new period,and solve the"non-agricultural""non-grain"and ecological problems of farmland.[Methods]Literature analysis and inductive deduction methods were used.[Results]The evolution of the farmland protection legal system has gone through the process of"national consciousness-policy guidelines-institutional system",the change from"single subject to multiple subjects";change from the use of"one-way administrative means to coordinated use of administrative,economic and technical means".The practical problems of the farmland protection legal system are mainly due to the insufficient systematization of the farmland protection legal system itself,the generalization of quantity protection,the transformation of quality protection,and the absence of ecological protection.[Conclusions]It is recommended to improve the existing farmland protection legal system from the establishment of the Farmland Protection Law,the improvement of the farmland protection public participation mechanism and supervision mechanism,the establishment of the farmland quality construction and improvement system,the differentiated farmland occupation and supplementation balance system,and the ecological restoration system. 展开更多
关键词 Farmland protection Legal system construction Policy evolution existing problems Optimization path
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The Problems and Solutions of Enterprise Financial Management in the Perspective of Digital Economy
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作者 Taoyuan Wan 《Proceedings of Business and Economic Studies》 2024年第5期206-212,共7页
From the perspective of the digital economy,enterprise financial management is facing unprecedented challenges and opportunities.Traditional financial management models are no longer suited to current development need... From the perspective of the digital economy,enterprise financial management is facing unprecedented challenges and opportunities.Traditional financial management models are no longer suited to current development needs.Fine-tuning financial management is essential to support the modernization of enterprises,guard against operational risks,and promote coordination across the entire value chain for greater economic efficiency.With the help of digital technology,data-driven,highly interconnected,and intelligent decision-making processes are becoming more prominent,profoundly transforming the operational and financial management models of enterprises.This enables financial management to keep pace with modern developments.In light of this,the paper explores the connotations and mechanisms of the digital economy and enterprise financial management,clarifies relevant conceptual characteristics,and identifies problems in financial management under the digital economy.It also offers strategies for optimization and problem-solving,with the aim of providing valuable insights for educators and practitioners. 展开更多
关键词 Digital economy ENTERPRISE Financial management existence problems Solution strategy
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EXISTENCE AND UNIQUENESS FOR THIRD ORDER NONLINEAR BOUNDARY VALUE PROBLEMS 被引量:5
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作者 WANG GUOCAN Department of Basic Science, Dalian Institute of Railway Technology, Dalian 116022 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1996年第1期7-16,共10页
In this paper, the existence and uniqueness of solutions for boundary valueproblem x′′′=f(t, x, x′, x″), x(0)=A, x′(0)=B, g(x′(1), x″(1))=0 are studied byusing Volterra type operator and upper and lower soluti... In this paper, the existence and uniqueness of solutions for boundary valueproblem x′′′=f(t, x, x′, x″), x(0)=A, x′(0)=B, g(x′(1), x″(1))=0 are studied byusing Volterra type operator and upper and lower solutions. Our results improve someknown works. 展开更多
关键词 Third order nonlinear boundary value problem existence and uniqueness Volterra type operator upper and lower solutions.
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Existence of solutions of nonlinear two-point boundary value problems for 4nth-order nonlinear differential equation 被引量:3
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作者 GAO Yong-xin(高永馨) 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2002年第4期424-428,共5页
Studies the existence of solutions of nonlinear two point boundary value problems for nonlinear 4n-th-order differential equationy (4n)=f(t,y,y′,y″,...,y (4n-1))(a)with the boundary conditions g 2i(y (2i)(a),y (2i+1... Studies the existence of solutions of nonlinear two point boundary value problems for nonlinear 4n-th-order differential equationy (4n)=f(t,y,y′,y″,...,y (4n-1))(a)with the boundary conditions g 2i(y (2i)(a),y (2i+1)(a))=0,h 2i(y (2i)(c),y (2i+1)(c))=0,(i=0,1,...,2n-1)(b) where the functions f, g i and h i are continuous with certain monotone properties. For the boundary value problems of nonlinear nth order differential equationy (n)=f(t,y,y′,y″,...,y (n-1))many results have been given at the present time. But the existence of solutions of boundary value problem (a),(b) studied in this paper has not been covered by the above researches. Moreover, the corollary of the important theorem in this paper, i.e. existence of solutions of the boundary value problem.y (4n)=f(t,y,y′,y″,...,y (4n-1)) a 2iy (2i)(a)+a 2i+1y (2i+1)(a)=b 2i,c 2iy (2i)(c)+c 2i+1y (2i+1)(c)=d 2i,(i=0,1,...2n-1)has not been dealt with in previous works. 展开更多
关键词 NONLINEAR 4n-th order DIFFERENTIAL EQUATION NONLINEAR two point BOUNDARY VALUE problems existENCE of solutions
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EXISTENCE AND UNIQUENESS RESULTS FOR BOUNDARY VALUE PROBLEMS OF HIGHER ORDER FRACTIONAL INTEGRO-DIFFERENTIAL EQUATIONS INVOLVING GRONWALL'S INEQUALITY IN BANACH SPACES 被引量:2
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作者 Dimplekumar N. CHALISHAJAR K. KARTHIKEYAN 《Acta Mathematica Scientia》 SCIE CSCD 2013年第3期758-772,共15页
We study boundary value problems for fractional integro-differential equations involving Caputo derivative of order α∈ (n-1, n) in Banach spaces. Existence and uniqueness results of solutions are established by vi... We study boundary value problems for fractional integro-differential equations involving Caputo derivative of order α∈ (n-1, n) in Banach spaces. Existence and uniqueness results of solutions are established by virtue of the Holder's inequality, a suitable singular Cronwall's inequality and fixed point theorem via a priori estimate method. At last, examples are given to illustrate the results. 展开更多
关键词 Boundary value problems fractional order integro-differential equations bound-ary value problems existence and uniqueness singular gronwall inequality fixed point theorem
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LOCAL EXISTENCE OF SOLUTION TO FREE BOUNDARY VALUE PROBLEM FOR COMPRESSIBLE NAVIER-STOKES EQUATIONS 被引量:3
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作者 刘健 《Acta Mathematica Scientia》 SCIE CSCD 2012年第4期1298-1320,共23页
This paper is concerned with the free boundary value problem for multidimensional Navier-Stokes equations with density-dependent viscosity where the flow density vanishes continuously across the free boundary. Local ... This paper is concerned with the free boundary value problem for multidimensional Navier-Stokes equations with density-dependent viscosity where the flow density vanishes continuously across the free boundary. Local (in time) existence of a weak solution is established; in particular, the density is positive and the solution is regular away from the free boundary. 展开更多
关键词 Navier-Stokes equations free boundary value problem local existence
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EXISTENCE AND UNIQUENESS OF POSITIVE SOLUTION FOR NONLINEAR SINGULAR 2mth-ORDER CONTINUOUS AND DISCRETE LIDSTONE BOUNDARY VALUE PROBLEMS 被引量:1
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作者 苑成军 文香丹 蒋达清 《Acta Mathematica Scientia》 SCIE CSCD 2011年第1期281-291,共11页
By fixed point theorem of a mixed monotone operators, we study Lidstone boundary value problems to nonlinear singular 2mth-order differential and difference equations, and provide sufficient conditions for the existen... By fixed point theorem of a mixed monotone operators, we study Lidstone boundary value problems to nonlinear singular 2mth-order differential and difference equations, and provide sufficient conditions for the existence and uniqueness of positive solution to Lidstone boundary value problem for 2mth-order ordinary differential equations and 2mth-order difference equations. The nonlinear term in the differential and difference equation may be singular. 展开更多
关键词 Mixed monotone operator fixed point theorem boundary value problems existence UNIQUENESS
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Existing Problems of Intensive Curing Barn and Optimization Analysis 被引量:1
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作者 左业华 雷庭 +2 位作者 王远辉 刘会忠 卢顺友 《Agricultural Science & Technology》 CAS 2014年第8期1271-1273,共3页
Intensive curing barn is an important component of flue-cured tobacco pro-duction in China, with progress made. However, problems stil exist, such as lower heat energy utilization efficiency and slow equipment update.... Intensive curing barn is an important component of flue-cured tobacco pro-duction in China, with progress made. However, problems stil exist, such as lower heat energy utilization efficiency and slow equipment update. In the research, opti-mization ways of tobacco barn were analyzed in flue-cured tobacco production re-gions, and assessment was made on improvement effects, in order to provide refer-ences for highly-efficient and low-carbon development of curing barn. 展开更多
关键词 Intensive curing barn existing problems Optimization analysis
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On the Existence of Positive Solution for a Nonlinear Third-order Three-point Boundary Value Problem 被引量:6
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作者 姚庆六 《Northeastern Mathematical Journal》 CSCD 2003年第3期244-248,共5页
An existence theorem of positive solution is established for a nonlinear third-order three-point boundary value problem. Here, we concentrated on the case that the nonlinear term is neither superlinear nor sublinear, ... An existence theorem of positive solution is established for a nonlinear third-order three-point boundary value problem. Here, we concentrated on the case that the nonlinear term is neither superlinear nor sublinear, and is not asymptotic at zero and infinity. 展开更多
关键词 third-order ordinary differential equation three-point boundary value problem positive solution existENCE
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EXISTENCE AND NONEXISTENCE OF GLOBAL SOLUTIONS OF THE INITIAL-BOUNDARY VALUE PROBLEM FOR SOME DEGENERATE HYPERBOLIC EQUATION 被引量:1
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作者 叶耀军 《Acta Mathematica Scientia》 SCIE CSCD 2005年第4期703-709,共7页
The author considers the global existence and global nonexistence of the initial-boundary value problem for some degenerate hyperbolic equation of the form utt- div(|△↓|^P-2 △↓u)=|u|^m u, (x,t)∈[0, +∞)... The author considers the global existence and global nonexistence of the initial-boundary value problem for some degenerate hyperbolic equation of the form utt- div(|△↓|^P-2 △↓u)=|u|^m u, (x,t)∈[0, +∞) ×Ω with p 〉 2 and m 〉 0. He deals with the global solutions by D.H.Sattinger's potential well ideas. At the same time, when the initial energy is positive, but appropriately bounded, the global nonexistence of solutions is verified by using the analysis method. 展开更多
关键词 Degenerate hyperbolic equations global existence and global nonexistence initial-boundary value problem
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EXISTENCE RESULTS FOR SEMIPOSITONE BOUNDARY VALUE PROBLEMS 被引量:4
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作者 马如云 王汝发 任立顺 《Acta Mathematica Scientia》 SCIE CSCD 2001年第2期189-195,共7页
The authors study the existence of positive solutions to the boundary value problem where f and e: [r,R] x [0,∞) → R are two continuous functions satisfying f 0 and |e| M for some M > 0. The authors show that... The authors study the existence of positive solutions to the boundary value problem where f and e: [r,R] x [0,∞) → R are two continuous functions satisfying f 0 and |e| M for some M > 0. The authors show that there exists at least one positive solution in the following two cases: (i) f is superlinear at infinity and λ > 0 is small enough; (ii) f is sublinear at infinity and λ > 0 is large enough. Their proofs are based on fixed point theorems in cones. 展开更多
关键词 existENCE positive solution boundary value problem CONE
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EXISTENCE OF BOUNDARY VALUE PROBLEMS FOR TFD EQUATION IN QUANTUM MECHANICS
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作者 王国灿 丁培柱 郑成德 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第2期243-248,共6页
TFD ( Thomas-Fermi-Dirac) equation in quantum mechanics is established. The existence theorems of the solutions are obtained by singular boundary value problem theory of ordinary differential equation and upper and lo... TFD ( Thomas-Fermi-Dirac) equation in quantum mechanics is established. The existence theorems of the solutions are obtained by singular boundary value problem theory of ordinary differential equation and upper and lower solution method. 展开更多
关键词 TFD equation singular boundary value problem existENCE upper and lower solution
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EXISTENCE AND UNIQUENESS FOR SECOND-ORDER VECTOR BOUNDARY VALUE PROBLEM OF NONLINEAR SYSTEMS
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作者 Du Zengji Lin Xiaojie Ge Weigao 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2005年第3期323-330,共8页
This paper is concerned with the following second-order vector boundary value problem :x^R=f(t,Sx,x,x'),0〈t〈1,x(0)=A,g(x(1),x'(1))=B,where x,f,g,A and B are n-vectors. Under appropriate assumptions,exis... This paper is concerned with the following second-order vector boundary value problem :x^R=f(t,Sx,x,x'),0〈t〈1,x(0)=A,g(x(1),x'(1))=B,where x,f,g,A and B are n-vectors. Under appropriate assumptions,existence and uniqueness of solutions are obtained by using upper and lower solutions method. 展开更多
关键词 vector differential equation nonlinear boundary value problem existence and uniqueness upper and lower solutions method.
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Existence of an Asymptotic Second-order Three-point Boundary Value Problem
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作者 江秀芬 姚庆六 《Northeastern Mathematical Journal》 CSCD 2003年第2期123-126,共4页
By making use of degree theory, a new existence theorem is established for an asymptotic second-order three-point boundary value problem.
关键词 second-order asymptotic equation three-point boundaxy value problem existence theorem
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Research on Causes and Countermeasures of Existing Problems in Tourism Signage System
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作者 Niu Wei 《Management Studies》 2021年第3期220-225,共6页
China takes the road of tourism development,and the tourism industry is gradually branded,which is also a reflect of tourism management to adapt to the trend of the times.Tourism is an important economic project for t... China takes the road of tourism development,and the tourism industry is gradually branded,which is also a reflect of tourism management to adapt to the trend of the times.Tourism is an important economic project for the participation of the whole people.By optimizing the local resources,the tourism space is carried out in an orderly manner,and the rich tourism products are displayed in front of the tourists.With the development of tourism,the scientific tourism system has been established,and the globalization of tourism has been realized.To promote the healthy development of tourism,tourist signs are essential.From the current established tourism signage system,there are still some problems,which affect the quality of tourism management.It is necessary to take corresponding countermeasures.This paper focuses on the causes and strategies in response to the existing problems in the tourism signage system. 展开更多
关键词 tourism signage system existing problems COUNTERMEASURES
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The Existing Structural Problems in World Economy
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《Contemporary International Relations》 1995年第4期6-12,共7页
Since the seventies,world economy has been engaged in adjustment princi-pally in the following three fields.First,the shift of economic developmentmode from that of aggregate quantitative growth to that of quality-eff... Since the seventies,world economy has been engaged in adjustment princi-pally in the following three fields.First,the shift of economic developmentmode from that of aggregate quantitative growth to that of quality-effective-ness.Second,the reform of economic system with more and more countries realiz-ing market economy.Third,the economy getting more opened as economic global-ization further avdances. 展开更多
关键词 The existing Structural problems in World Economy World
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Existence and iteration of monotone positive solutions for a third-order two-point boundary value problem 被引量:5
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作者 SUN Yong-ping 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第4期413-419,共7页
The existence of nondecreasing positive solutions for the nonlinear third-order twopoint boundary value problem u′″(t) + q(t)f(t,u(t),u′(t)) = 0, 0 〈 t 〈 1, u(0) = u″(0) = u′(1) = 0 is studied.... The existence of nondecreasing positive solutions for the nonlinear third-order twopoint boundary value problem u′″(t) + q(t)f(t,u(t),u′(t)) = 0, 0 〈 t 〈 1, u(0) = u″(0) = u′(1) = 0 is studied. The iterative schemes for approximating the solutions are obtained by applying a monotone iterative method. 展开更多
关键词 third-order two-point boundary value problem monotone iterative method positive solution existence iterative scheme
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EXISTENCE OF POSITIVE SOLUTIONS FOR A CLASS OF SINGULAR TWO POINT BOUNDARY VALUE PROBLEMS OF SECOND ORDER NONLINEAR EQUATION
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作者 杨作东 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1996年第5期465-476,共12页
In this paper, we establish the existence of positive solutions of (|y'| p-2g' )'+f(t,y)= 0 (P>1 ). y (0)=y (1) = 0. The function f is allowed to be singular when y= 0.
关键词 singular boundary value problems NONLINEAR positive solution existENCE
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Practice,Existing Problems and Countermeasures of Tobacco Planting Insurance in Qianxinan Prefecture
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作者 Qing MU Yang LIU +3 位作者 Binhua ZHAN Feng DING Qixue CHEN Chuanjiang FEI 《Agricultural Biotechnology》 CAS 2018年第6期152-155,共4页
The cultivation of the economic crop flue-cured tobacco is greatly impacted by natural climates,making it a risk industry.In recent years,flue-cured tobacco production is influenced by extreme weather such as typhoon,... The cultivation of the economic crop flue-cured tobacco is greatly impacted by natural climates,making it a risk industry.In recent years,flue-cured tobacco production is influenced by extreme weather such as typhoon,low temperature,hail,frost,drought,plant diseases and insect pests.It is imperative to establish a sound insurance system for tobacco planting.In this paper,the practice and functions of tobacco planting insurance in Qianxinan Prefecture were summarized,the experience and existing problems in the practice process were analyzed,and finally the countermeasures and suggestions were proposed to further improve the tobacco planting insurance. 展开更多
关键词 TOBACCO PLANTING INSURANCE existing problems COUNTERMEASURES Qianxinan Prefecture GUIZHOU
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EXISTENCE AND NONEXISTENCE FOR THE INITIAL BOUNDARY VALUE PROBLEM OF ONE CLASS OF SYSTEM OF MULTIDIMENSIONAL NONLINEAR SCHRDINGER EQUATIONS WITH OPERATOR AND THEIR SOLITON SOLUTIONS 被引量:3
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作者 郭柏灵 《Acta Mathematica Scientia》 SCIE CSCD 1989年第1期45-56,共12页
The nonlinear interactions between the monochromatic wave have been considered by K. Matsunchi, who also proposed one class of the nonlinear Schrdinger equation system with wave operator. We also obtain the same type ... The nonlinear interactions between the monochromatic wave have been considered by K. Matsunchi, who also proposed one class of the nonlinear Schrdinger equation system with wave operator. We also obtain the same type of equations, which are satisfied by transverse velocity of higher frequency electron, as we study soliton in plasma physics. In this paper, under some condition we study the existence and nonexistence for this equations in the cases possessing different signs in nonlinear term. 展开更多
关键词 DINGER EQUATIONS WITH OPERATOR AND THEIR SOLITON SOLUTIONS existENCE AND NONexistENCE FOR THE INITIAL BOUNDARY VALUE problem OF ONE CLASS OF SYSTEM OF MULTIDIMENSIONAL NONLINEAR SCHR
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