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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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ON THE EXISTENCE AND NODAL CHARACTER OF SOLUTIONS OF SINGULAR NONLINEAR BOUNDARY VALUE PROBLEMS 被引量:1
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作者 曹道珉 邓引斌 《Acta Mathematica Scientia》 SCIE CSCD 1990年第4期471-478,共8页
In this paper we prove the existence of k-node solution of singular nonlinear boundary value problems for each k is-an-element-of N union {0}.
关键词 ON THE existence AND NODAL CHARACTER OF SOLUTIONS OF SINGULAR NONLINEAR BOUNDARY VALUE problems BVP
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On the Experience, Problems in Science and Technology Services of Basic Scientific Research Institutes and Suggestions——Taking Zhenjiang Institute of Agricultural Sciences in Hilly Areas of Jiangsu as an Example
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作者 王敬根 单延博 +1 位作者 曲直 刘照亭 《Agricultural Science & Technology》 CAS 2017年第12期2681-2683,2686,共4页
Taking the Jiangsu Province as Zhenjiang Academy of Agricultural Sciences in Hilly Areas of an example, the paper elaborated the advanced practices of agricultural research institutes in agricultural science and techn... Taking the Jiangsu Province as Zhenjiang Academy of Agricultural Sciences in Hilly Areas of an example, the paper elaborated the advanced practices of agricultural research institutes in agricultural science and technology services and analyzed the difficulties and solutions in the services. process of science and technologyservices. 展开更多
关键词 Basic scientific research institutes Science and technology services EXPERIENCE Existing problems SOLUTIONS
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Development Status and Countermeasures of Farmers' Professional Cooperatives in Shangqiu City
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作者 Xiaofan XIAO 《Agricultural Biotechnology》 2024年第3期41-44,共4页
Farmers' professional cooperatives develop in various forms,and with the continuous improvement of development level,social effects have gradually appear.Based on the specific situation of farmers' professiona... Farmers' professional cooperatives develop in various forms,and with the continuous improvement of development level,social effects have gradually appear.Based on the specific situation of farmers' professional cooperatives in Shangqiu City,this paper expounded the development status of farmers' professional cooperatives in Shangqiu City,analyzed and discussed various problems encountered in the development process of farmers' professional cooperatives,and put forward some countermeasures and suggestions,such as establishing and perfecting cooperative rules and regulations,financing from multiple channels,introducing technical talents in various ways,breaking the information asymmetry restriction by various means,and giving full play to government functions,aiming to further promote standardized,large-scale,healthy and sustainable development of farmers' professional cooperatives. 展开更多
关键词 Farmers'professional cooperatives Shangqiu city Development status Existing problems Countermeasure analysis
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Problems and Strategies for Arable Land Eco-conservation in China 被引量:2
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作者 杨诗琴 杨子生 《Agricultural Science & Technology》 CAS 2017年第7期1355-1357,1360,共4页
Arable lands are so important to China concerning food security and ec- onomy development. And eco-problems are rising and food security risks are widespread. The research reviewed quantity and quality of domestic ara... Arable lands are so important to China concerning food security and ec- onomy development. And eco-problems are rising and food security risks are widespread. The research reviewed quantity and quality of domestic arable lands, analyzed existing problems and proposed countermeasures for reinforcing domestic arable land conservation. 展开更多
关键词 Arable land Eco-conservation Existing problems STRATEGIES China
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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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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 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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A Preliminary Study on the Problems and Improvement of the Latest Land Use Classification System in China
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作者 Qiuju WU Zisheng YANG 《Asian Agricultural Research》 2021年第7期32-34,共3页
The establishment of a unified land use classification system is the basis for realizing the unified management of land and sea,urban and rural areas,and aboveground and underground space.In November 2020,the Ministry... The establishment of a unified land use classification system is the basis for realizing the unified management of land and sea,urban and rural areas,and aboveground and underground space.In November 2020,the Ministry of Natural Resources of the People's Republic of China issued the Classification Guide for Land and Space Survey,Planning and Use Control of Land and Sea(for Trial Implementation),which aims to establish a national unified land and sea use classification system,lay an important foundation for scientific planning and unified management of natural resources,rational use and protection of natural resources,and speed up the construction of a new pattern of land and space development and protection.However,there are still some obvious shortcomings in the Classification Guide.This paper analyzes some problems existing in this classification standard from three aspects of logicality,rigorousness and comprehensiveness,and puts forward some suggestions for further improvement.This has important practical significance to better guiding the practice of land use and land resources management,and then to achieving the goal of unified management of natural resources. 展开更多
关键词 Land use Classification system Existing problems Suggestions for improvement
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AN APPLICATION OF SCHAUDER’S FIXED POINT THEOREM TO THE EXISTENCE OF SOLUTlONS OF IMPULSIVELY DIFFERENTIAL EQUATIONS
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作者 董玉君 邹尔新 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1995年第4期377-381,共5页
In this paper the existence of solutions of a boundary value problem forimpulsively differential equations that is difficult to solve by the upper and lowersolution method will be proved by means of Schauder’s fixed ... In this paper the existence of solutions of a boundary value problem forimpulsively differential equations that is difficult to solve by the upper and lowersolution method will be proved by means of Schauder’s fixed point theorem,whichimproves some existing results. 展开更多
关键词 Schaudcr’s fixed point theorem boundary value problem existence of solutions
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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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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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A Study on the Problems and Countermeasures of English Vocabulary Teaching in Primary School
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作者 钱佩思 邵贤 《海外英语》 2021年第6期279-280,共2页
This paper analyzes the current situation of English vocabulary teaching in primary schools through a questionnaire sur⁃vey of 180 students in Liushi No.5 Primary School,and points out the existing problems.Then,some ... This paper analyzes the current situation of English vocabulary teaching in primary schools through a questionnaire sur⁃vey of 180 students in Liushi No.5 Primary School,and points out the existing problems.Then,some effective suggestions are put forward.The research in this paper is of great significance to helping primary school students improve their English vocabulary learning ability.Meanwhile,it can provide a powerful reference for how to enrich the primary school English vocabulary class and how to improve teaching efficiency. 展开更多
关键词 primary school English vocabulary teaching existing problems COUNTERMEASURES
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EXISTENCE AND NONEXISTENCE OF GLOBAL CONTINUOUS SOLUTIONS TO RIEMANN PROBLEM FOR DAMPED P-SYSTEM
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作者 林龙威 杨彤 《Acta Mathematica Scientia》 SCIE CSCD 1993年第1期1-12,共12页
In this paper, we extend the result in [16] to general p(v). We prove that, under condition (M), when P greater-than-or-equal-to 3/2, where P=pp triple overdot/p2, there exists a unique global continuous solution to t... In this paper, we extend the result in [16] to general p(v). We prove that, under condition (M), when P greater-than-or-equal-to 3/2, where P=pp triple overdot/p2, there exists a unique global continuous solution to the Riemann problem (E), (R), whose structure is similar to the local solution. When 1 < P* less-than-or-equal-to P* < 5/4, or P* = P* = 5/4, or 5 < P* less-than-or-equal-to P* < 3/2 where P*-inf/v P and P* = sup/v P for all v under consideration, if at least one of the initial centered rarefaction waves is sufficiently strong, then the solution must be breakdown in a finite time. 展开更多
关键词 existence AND NONexistence OF GLOBAL CONTINUOUS SOLUTIONS TO RIEMANN PROBLEM FOR DAMPED P-SYSTEM
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EXISTENCE OF NONTRIVIAL SOLUTION OF QUASILINEAR ELLIPTIC EIGENVALUE PROBLEM ON R^n WITH NATURAL GROWTH CONDITIONS
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作者 严树森 李工宝 《Acta Mathematica Scientia》 SCIE CSCD 1990年第2期121-134,共14页
In this paper, we get the existence result of the nontrivial weak solution (λ, u) of the following eigenvalue problem with natural growth conditions.
关键词 existence OF NONTRIVIAL SOLUTION OF QUASILINEAR ELLIPTIC EIGENVALUE PROBLEM ON R~n WITH NATURAL GROWTH CONDITIONS
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Problems existing in water resources development and the countermeasures in northwest China continental basins
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《Global Geology》 1998年第1期57-58,共2页
关键词 problems existing in water resources development and the countermeasures in northwest China continental basins
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A discussion on producing agro-residue composites with isocyanate resins 被引量:2
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作者 顾继友 高振华 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第1期74-76,84,共3页
With the urgent shortage of forest resource in China, using agro-residues as raw materials of composite become increasingly important. Agro-residue is the most potential fiber resource, which is helpful to sustainable... With the urgent shortage of forest resource in China, using agro-residues as raw materials of composite become increasingly important. Agro-residue is the most potential fiber resource, which is helpful to sustainable development of composite industries in China. Based on a great deal of researches, this paper summarized and discussed some problems in using agro-residues as raw materials of composites, including raw material preparation, hot-pressing, bonding technology, preventing composite from going moldy. It is proposed that to manufacture the composite of rice straws or wheat straws, the isocayante resin is a suitable adhesive, and the appropriate technologies, bonding, and treatment measures are also needed. 展开更多
关键词 Agro-residue Isocyanate resin Composite problems existing
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Thoughts on Building Nanchang a Forestry City
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作者 陈晓刚 林辉 罗悦平 《Agricultural Science & Technology》 CAS 2014年第7期1216-1218,共3页
From the concept of urban forest and status quo of urban forest in Nanchang,the problems existing on urban forest were proposed,as well as countermeasures and suggestions.
关键词 Urban forest Existing problems Policy and suggestions Nanchang
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A Review of Recent Advances in Research on Asian Monsoon in China 被引量:15
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作者 何金海 琚建华 +2 位作者 温之平 吕俊梅 金放华 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2007年第6期972-992,共21页
This paper reviews briefly advances in recent research on monsoon by Chinese scholars, including primarily: (1) the establishment of various monsoon indices. In particular, the standardized dynamic seasonal variabi... This paper reviews briefly advances in recent research on monsoon by Chinese scholars, including primarily: (1) the establishment of various monsoon indices. In particular, the standardized dynamic seasonal variability index of the monsoon can delimit the geographical distribution of global monsoon systems and determine quantitatively the date of abrupt change in circulation. (2) The provision of three driving forces for the generation of monsoon. (3) The revelation of the heating-pump action of the Tibetan Plateau, which strengthens southerlies in the southern and southeastern periphery of the Plateau and results in a strong rainfall center from the northern Bay of Bengal (BOB) to the Plateau itself. (4) Clarification of the initial onset of the Asian Summer Monsoon (ASM) in the BOB east of 90°E, Indochina Peninsula (ICP) and the South China Sea, of which the rapid northward progression of tropical convection in the Sumatra and the rapid westward movement of the South Asia High to the Indochina Peninsula are the earliest signs. (5) The provision of an integrated mechanism for the onset of the East Asian Summer Monsoon (EASM), which emphasizes the integrated impact of sensible heat over Indian Peninsula, the warm advection of the Tibetan Plateau and the sensible heat and latent heat over the Indochina Peninsula on the one hand, and the seasonal phase-lock effect of the northward propagation of low frequency oscillation on the other. (6) The revelation of the "planetary-scale moisture transport large-value band" from the Southern Hemisphere through to the Asian monsoon region and into the North Pacific, which is converged by several large-scale moisture transport belts in the Asian-Australian monsoon regions and whose variation influences directly the temporal and spatial distribution of summer rainfall in China. (7) Presenting the features of the seasonal advance of the EASM, the propagation of intraseasonal oscillation, and their relationship with rainfall in China; indicating that the intraseasonal oscillation of the EASM propagates in the form of a wave-train along the coast and behaves as monsoon surge propagating northward. (8) Describing the interannual and interdecadal variation of Asian monsoon, revealing the factors affecting it, and possible mechanisms of the variation of Asian monsoon. An elementary outlook on the existing problems and future direction of monsoon research is also provided. 展开更多
关键词 recent research MONSOON China review ADVANCES existing problems PROSPECTS
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Research Progress in National Land Use Planning and Implementation Guarantee System
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作者 瞿如一 杨子生 《Agricultural Science & Technology》 CAS 2017年第6期1106-1108,共3页
Land use plan serves as a leading role in land resource management, necessitating a powerful implementation guarantee system. The research concluded researches on guarantee system for land use plan from law, administr... Land use plan serves as a leading role in land resource management, necessitating a powerful implementation guarantee system. The research concluded researches on guarantee system for land use plan from law, administration, econo- my, society and technology. Finally, existing problems and suggestions were pro- posed. 展开更多
关键词 Land use planning Implementation guarantee system Research status quo Existing problem COUNTERMEASURES
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