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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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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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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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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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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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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:2
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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 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 Review of Recent Advances in Research on Asian Monsoon in China 被引量:13
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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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A Research on Oral English Competence of English Majors in XFU
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作者 任芳 《海外英语》 2018年第11期242-243,共2页
Nowadays, it is obvious to see the importance of oral English competence. Cultivating students' oral English competence is not only the need of the development of the society but also the development of college st... Nowadays, it is obvious to see the importance of oral English competence. Cultivating students' oral English competence is not only the need of the development of the society but also the development of college students. This paper will analyze existing problems of English majors in Xi'an Fanyi University. Based on this, the author will put forward some countermeasures to improve their oral English competence. 展开更多
关键词 oral English existing problems COUNTERMEASURES
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Protection of Metasequoia glyptostroboides Hu et Cheng in China
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作者 WANG Xi-qun GUO Bao-xiang 《Forestry Studies in China》 CAS 2009年第4期249-257,共9页
Metasequoia (Metasequoia glyptostroboides Hu et Cheng) is an important but endangered tree species. In a sense, the course of protection of the metasequoia can be considered a miniature of the history of the protect... Metasequoia (Metasequoia glyptostroboides Hu et Cheng) is an important but endangered tree species. In a sense, the course of protection of the metasequoia can be considered a miniature of the history of the protection of rare Chinese plants over the past 50 years. The approval and establishment of the National Class Nature Reserve for metasequoia is a milestone in this course. A thorough understanding of this course is beneficial to design the correct future protection plans and for taking effective measures. In this paper the entire protection course of metasequoia is reviewed, three detailed measures are proposed according to the present situation and existing problems and discussed as follows. 1) We should reinforce unceasingly the establishment of National Nature Reserves of metasequoia, put emphasis on the protection of the original natural mother trees (ONMTs) of metasequoia, design far- sighted projects to protect the ONMTs and strictly implement and enforce the regulations or laws regarding the protection of meta- sequoia. The establishment and functions of the organization should meet the demands of protecting the ONMTs and developing metasequoias. The budget should support and the quality of the personnel assigned to this task should satisfy the protection and de- velopment of the ONMTs. We should also promote the complete protection of the ONMTs at the same time and strengthen the pro- tection and restoration of the ONMTs and their ecosystem in the Xiaohe valley, Lichuan County, Hubei Province, one of the natural concentration areas of ONMTs in the world. 2) A gene bank should be established for comprehensive protection of the genes of ex- isting original mother trees of metasequoia. 3) The key is to study the theoretical fundamentals of restoration and re-establishment of natural vegetation of metasequoia in the Xiaohe valley to harmonize the relation among environmental departments, forestry sectors, academies of sciences and other educational or research units, to carry out scientific research and strengthen academic exchanges to promote jointly the protection and utilization of metasequoia and other natural resources in China. 展开更多
关键词 Metasequoia glyptostroboides Hu et Cheng original mother trees protection course existing problems
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Current Development Status of Cucumber Industry in Linyi City and Countermeasures for Improving Quality and Benefits
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作者 Yongtao ZHANG Xuyuan ZHOU +2 位作者 Peng LENG Zhaoshuai GU Deqiang CAO 《Asian Agricultural Research》 2020年第5期21-24,共4页
In order to expand and strengthen the cucumber industry in Linyi City of Shandong City and make it more effective in revitalizing the rural economy,the authors surveyed the current situation of the cucumber planting a... In order to expand and strengthen the cucumber industry in Linyi City of Shandong City and make it more effective in revitalizing the rural economy,the authors surveyed the current situation of the cucumber planting area,production management,fresh-keeping processing and marketing in Linyi City.Based on the survey,it analyzed the current problems in the development of the cucumber industry in Linyi City,including low level of facilities and equipment,the post-picking processing technology,the imperfect quality control system,the low degree of information and the weak degree of organization.Finally,it came up with recommendations including developing increasing modern technological innovation of facility structure and equipment,accelerating research on post-picking commercial processing technology of cucumber,accelerating the construction of product quality traceability system,promoting in-depth integration of informationization and cucumber industry,and improving the degree of organization and industrialization,to improve the quality and benefits of cucumber industry,so as to provide guidance for improving the overall quality,benefit and market competitiveness of cucumber industry in Linyi City. 展开更多
关键词 Cucumber industry Linyi City Current development status Existing problems Quality and benefit improvement COUNTERMEASURES
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Opening and Sharing of Large-scale Instruments and Equipment in Agricultural Research Institutes:A Case Study of Environment and Plant Protection Institute of Chinese Academy of Tropical Agricultural Sciences
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作者 Yanmei CUI Xiaoqiang CHU +3 位作者 Huaping HUANG Xinchun ZHANG Ye LI Shuchang WANG 《Asian Agricultural Research》 2020年第12期6-11,共6页
The article introduces the main practices and achievements of the Environment and Plant Protection Institute of Chinese Academy of Tropical Agricultural Sciences in promoting the sharing of large-scale instruments and... The article introduces the main practices and achievements of the Environment and Plant Protection Institute of Chinese Academy of Tropical Agricultural Sciences in promoting the sharing of large-scale instruments and equipment in recent years,analyzes the existing problems in the management system,management team,assessment incentives and maintenance guarantee,and proposes improvement measures and suggestions from aspects of improving the sharing management system,strengthening management team building,strengthening sharing assessment and incentives,improving maintenance capabilities and expanding external publicity,to further improve the sharing management of large-scale instruments and equipment. 展开更多
关键词 Agricultural scientific research institution Large-scale instrument and equipment Opening and sharing Existing problem SUGGESTION
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Supervisory Monitoring of Ecological Environment of Marine Nature Reserve
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作者 HUANG Bei SHAO Junbo +1 位作者 ZHOU Bin MA Xueying 《Journal of Landscape Research》 2016年第2期37-39,42,共4页
According to the latest situation of marine nature reserves in China, major problems in the construction of China's marine nature reserves and causes were analyzed. Considering related laws and regulations as well... According to the latest situation of marine nature reserves in China, major problems in the construction of China's marine nature reserves and causes were analyzed. Considering related laws and regulations as well as requirements of China's ecological environment protection, this paper pointed out the necessity and urgency of implementing supervisory monitoring over marine nature reserves, and suggested that Ministry of Environmental Protection should take the lead, marine, forestry, land resources and other departments in charge should cooperate to fulfi ll this task, the supervisory monitoring should cover ecological environment, protected objects, routine work of the nature reserve management agency, and the authority of supervisory monitoring results should be highlighted. 展开更多
关键词 Marine nature reserve Existing problems Supervisory monitoring Countermeasures and suggestions
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Reflections on Plain Greening in Coastal Urban Areas: A Case Study of Plain Greening in the Main Urban Area of Taizhou
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作者 Zhang Yunsheng Lu Wenmei 《Meteorological and Environmental Research》 CAS 2018年第2期47-49,57,共4页
The current situation,existing problems and characteristics of greening in the main urban area of Taizhou were analyzed,and the construction ideas and safeguard measures of plain greening in urban areas in the new era... The current situation,existing problems and characteristics of greening in the main urban area of Taizhou were analyzed,and the construction ideas and safeguard measures of plain greening in urban areas in the new era were put forward. 展开更多
关键词 Coastal plains Main urban area Plain greening Existing problems Construction ideas Safeguard measures
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The Schizophrenic Utterance in Chris Kraus’s I Love Dick
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作者 马春玉 《海外英语》 2021年第1期209-211,共3页
The novel I Love Dick,written by Chris Kraus,discusses the“least described”social problem.The novel starts with describing Chris’s love affair.Her love affair is narrated with her illustrations of some social probl... The novel I Love Dick,written by Chris Kraus,discusses the“least described”social problem.The novel starts with describing Chris’s love affair.Her love affair is narrated with her illustrations of some social problems that are shrunk into personal problems.This article aims to examine how she uses the schizophrenic utterances to illustrate the failure of her love affair differently. 展开更多
关键词 Chris Kraus’s I Love Dick the problem of Existing Language Unbridgeable the Schizophrenic Utterance a New Possibility
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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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