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Assessing the Efficacy of Wheat-Soybean Based Intercropping System at Different Plant Densities in Bambili, Cameroon
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作者 Lendzemo E. Tatah Jeazet K. Teitiogo +3 位作者 Oben Tom Tabi Tange D. Achiri Njualem D. Khumbah Chi Christopher Tamu 《American Journal of Plant Sciences》 CAS 2024年第4期235-251,共17页
Wheat is one of the most important cereals in the world, serving as a staple for millions globally. In the wake of the geopolitical crisis between Russia and Ukraine, it has become incumbent for many countries to inve... Wheat is one of the most important cereals in the world, serving as a staple for millions globally. In the wake of the geopolitical crisis between Russia and Ukraine, it has become incumbent for many countries to invest in wheat production. Improving cropping systems for wheat production is paramount. Intercropping cereals with legumes has tremendous advantages. Therefore, this study was designed to optimize wheat production by intercropping it with soybean at different densities. Between March and August 2023, a randomized complete block design trial was conducted in Bambili, North West of Cameroon with treatments T1 (wheat monocrop at 200,000 plants ha<sup>−</sup><sup>1</sup>), T2 (soybean monocrop at 250,000 plants ha<sup>−</sup><sup>1</sup>), T3 (200,000 wheat and 125,000 soybean ha<sup>−</sup><sup>1</sup>), T4 (100,000 wheat and 250,000 soybean ha<sup>−</sup><sup>1</sup>), T5 (200,000 wheat and 250,000 soybean ha<sup>−</sup><sup>1</sup>) and T6 (100,000 wheat and 125,000 soybean ha<sup>−</sup><sup>1</sup>). Results revealed that growth parameters of wheat were not significantly influenced by monocrop or intercrop. The yield of wheat was significantly higher in the monocrop than the intercrop treatments, with slight variation amongst the intercrop treatments. Soybean yield was higher in the monocrop than in the intercrop, with no variations amongst the intercrop treatments. Only the land equivalence ratio (LER) for T5 was greater than 1.0. The competitive ratio for T5 was 0.54 for wheat and 1.90 for soybean, comparatively lower than the other monocrop treatments. Intercropping wheat and soybean at 200,000:250,000 ratio is recommended. 展开更多
关键词 Competitive Ration Land Equivalence Ration INTERCROP SOYBEAN WHEAT
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Modeling commuters' route choice behavior under pre-trip information system 被引量:2
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作者 李春燕 陈峻 +1 位作者 叶晓飞 郑竞恒 《Journal of Southeast University(English Edition)》 EI CAS 2012年第3期344-348,共5页
Research about the auto commuter's pre-trip route choice behavior ignores the combined influence of the real-time information and all respondents' historical information in the existing documents.To overcome this sh... Research about the auto commuter's pre-trip route choice behavior ignores the combined influence of the real-time information and all respondents' historical information in the existing documents.To overcome this shortcoming,an approach to describing the pre-trip route choice behavior with the incorporation of the real-time and historical information is proposed.Two types of real-time information are investigated,which are quantitative information and prescriptive information.By using the bounded rationality theory,the influence of historical information on the real-time information reference process is examined first.Estimation results show that the historical information has a significant influence on the quantitative information reference process,but not on the prescriptive information reference process.Then the route choice behavior is modeled.A comparison is also made among three route choice models,one of which does not incorporate the real-time information reference process,while the others do.Estimation results show that the route choice behavior is better described with the consideration of the reference process of both quantitative and prescriptive information. 展开更多
关键词 route choice pre-trip real-time information bounded rationality theory logit model
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Development of a Non-Pollution Orange Fruit Expert System Software Based on ASP.NET 被引量:10
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作者 LI Yi-shan HONG Li-fang 《Agricultural Sciences in China》 CAS CSCD 2011年第5期805-812,共8页
Based on ASP.NET,a orange fruit tree fertilizer expert system software was developed.The system could simulate and decide an annual fertilization plan for young and mature trees in terms of geographical position and c... Based on ASP.NET,a orange fruit tree fertilizer expert system software was developed.The system could simulate and decide an annual fertilization plan for young and mature trees in terms of geographical position and climate.This paper introduced the design conditions,framework,production,and deployment of the system.It exhibited characters of orange specialty and was a typical online agriculture expert system.The use of the system for orange fruit management could decrease production cost,guarantee orange quality and improve economical benefit at the same time.Farmer using the system saved N input by 41-238 g/plant,P2O5 input 3-24 g/plant,and K2O input 1-36 g/plant,and got higher yield by 6-17 kg/plant. 展开更多
关键词 rational fertilization expert system orange fruit tree ASP.NET
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A New Rational Algebraic Approach to Find Exact Analytical Solutions to a (2+1)-Dimensional System 被引量:7
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作者 BAI Cheng-Jie ZHAO Hong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第5X期801-810,共10页
In this paper, we present a new rational algebraic approach to uniformly construct a series of exact analytical solutions for nonlinear partial differential equations. Compared with most existing tanh methods and othe... In this paper, we present a new rational algebraic approach to uniformly construct a series of exact analytical solutions for nonlinear partial differential equations. Compared with most existing tanh methods and other sophisticated methods, the proposed method not only recovers some known solutions, but also finds some new and general solutions. The solutions obtained in this paper include rational form triangular periodic wave solutions, solitary wave solutions, and elliptic doubly periodic wave solutions. The efficiency of the method can be demonstrated on (2+1)-dimensional dispersive long-wave equation. 展开更多
关键词 rational algebraic approach (2+1)-dimensional dispersive long-wave equation exact solutions
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Spectral and Energy Efficiency of Downlink MU-MIMO Systems with MRT 被引量:4
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作者 Weiqiang Tan Shi Jin Jide Yuan 《China Communications》 SCIE CSCD 2017年第5期105-111,共7页
This paper studies the achievable spectral efficiency(SE)of downlink multiuser multiple-input-multiple-output(MIMO)system,where the base station(BS)is deployed an arbitrary finite antenna number and communicates simul... This paper studies the achievable spectral efficiency(SE)of downlink multiuser multiple-input-multiple-output(MIMO)system,where the base station(BS)is deployed an arbitrary finite antenna number and communicates simultaneously with many users. We assume that the BS has accurate channel state information(CSI)and adopt maximum ratio transmission(MRT)precoding. An accurate analytical result for the achievable SE is obtained. Based on the analytical result on the achievable SE,we further study the achievable energy efficiency(EE)of multiuser MIMO system by considering an energy consumption model. Results indicate that the increasing number of BS antennas can boost the achievable SE of system,whilst the achievable SE tends to a saturated rate in the high signal-tonoise ratios(SNR)regime. Furthermore,an important conclusion is that the increasing number of users is beneficial for the achievable EE and there is an optimal antenna number to maximize the EE of system. 展开更多
关键词 energy efficiency multiuser MIMO maximum ration transmission spectral efficiency
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Computation of the Rational Representation for Solutions of High-dimensional Systems 被引量:3
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作者 TAN CHANG ZHANG SHU-GONG 《Communications in Mathematical Research》 CSCD 2010年第2期119-130,共12页
This paper deals with the representation of the solutions of a polynomial system, and concentrates on the high-dimensional case. Based on the rational univari- ate representation of zero-dimensional polynomial systems... This paper deals with the representation of the solutions of a polynomial system, and concentrates on the high-dimensional case. Based on the rational univari- ate representation of zero-dimensional polynomial systems, we give a new description called rational representation for the solutions of a high-dimensional polynomial sys- tem and propose an algorithm for computing it. By this way all the solutions of any high-dimensional polynomial system can be represented by a set of so-called rational- representation sets. 展开更多
关键词 rational univariate representation high-dimensional ideal maximally independent set rational representation irreducible component
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CTE Solvability and Exact Solution to the Broer-Kaup System 被引量:3
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作者 CHEN Chun-Li LOU Sen-Yue 《Chinese Physics Letters》 SCIE CAS CSCD 2013年第11期6-9,共4页
A consistent tanh expansion(CTE)is used to solve the Broer–Kaup(BK)system.It is proved that the BK system is CTE solvable.Some exact interaction solutions among different nonlinear excitations such as solitons,ration... A consistent tanh expansion(CTE)is used to solve the Broer–Kaup(BK)system.It is proved that the BK system is CTE solvable.Some exact interaction solutions among different nonlinear excitations such as solitons,rational waves,periodic waves,error function waves and any Burgers waves are explicitly given. 展开更多
关键词 RATIONAL EXCITATION EXACT
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Optimal opportunistic maintenance model of multi-unit systems 被引量:3
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作者 Zhijun Cheng Zheng Yang Bo Guo 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第5期811-817,共7页
An opportunistic maintenance model is presented for a continuously deteriorating series system with economical de-pendence. The system consists of two kinds of units, which are respectively subjected to the deteriorat... An opportunistic maintenance model is presented for a continuously deteriorating series system with economical de-pendence. The system consists of two kinds of units, which are respectively subjected to the deterioration failure described by Gamma process and the random failure described by Poisson process. A two-level opportunistic policy defined by three decision parameters is proposed to coordinate the different maintenance actions and minimize the long-run maintenance cost rate of the system. A computable expression of the average cost rate is established by using the renewal property of the stochastic process of the maintained system state. The optimal values of three deci- sion parameters are derived by an iteration approach based on the characteristic of Gamma process. The behavior of the proposed policy is illustrated through a numerical experiment. Comparative study with the widely used corrective maintenance policy demonstrates the advantage of the proposed opportunistic maintenance method in significantly reducing the maintenance cost. Simultane- ously, the applicable area of this opportunistic model is discussed by the sensitivity analysis of the set-up cost and random failure rate. 展开更多
关键词 opportunistic maintenance policy multi-unit system economical dependence Gamma process continuously deterio- ration.
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Joint frequency offset tracking and PAPR reduction algorithm in OFDM systems 被引量:4
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作者 Lijun Ge Yingxin Zhao Hong Wu Ning Xu Yu'ang Jin Wenqi Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第4期557-561,共5页
This paper presents an algorithm that aims to reduce the peak-to-average power ratio(PAPR) of orthogonal frequency division multiplexing(OFDM) communication systems while maintaining frequency tracking.The algorit... This paper presents an algorithm that aims to reduce the peak-to-average power ratio(PAPR) of orthogonal frequency division multiplexing(OFDM) communication systems while maintaining frequency tracking.The algorithm achieves PAPR reduction by applying the complex conjugates of the data symbol obtained from the frequency domain to cancel the phase of the data symbol.A likelihood estimator is used to obtain the sub-carrier phase error due to the residual carrier frequency offset(RCFO) using the same complex conjugates as a pilot signal.Furthermore,a joint time and frequency domain multicarrier phase locked loop(MPLL) is developed to compensate additional frequency offset.Simulation results show that this algorithm is capable of reducing PAPR without impacting the frequency tracking performance. 展开更多
关键词 orthogonal frequency division multiplexing(OFDM) peak-to-average power ration(PAPR) carrier frequency offset complex conjugate multicarrier phase locked loop(MPLL) phase error.
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Modeling and verifying So S performance requirements of C4ISR systems 被引量:2
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作者 Yudong Qi Zhixue Wang +1 位作者 Qingchao Dong Hongyue He 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第4期754-763,共10页
System-of-systems (SOS) engineering involves a com- plex process of refining high-level SoS requirements into more detailed systems requirements and assessing the extent to which the performances of to-be systems ma... System-of-systems (SOS) engineering involves a com- plex process of refining high-level SoS requirements into more detailed systems requirements and assessing the extent to which the performances of to-be systems may possibly satisfy SoS capa- bility objectives. The key issue is how to model such requirements to automate the process of analysis and assessment. This paper suggests a meta-model that defines both functional and non- functional features of SoS requirements for command and control, communication, computer, intelligence, surveillance reconnais- sance (C41SR) systems. A domain-specific modeling language is defined by extending unified modeling language (UML) con- structed of class and association with fuzzy theory in order to model the fuzzy concepts of performance requirements. An effi- ciency evaluation function is introduced, based on Bezier curves, to predict the effectiveness of systems. An algorithm is presented to transform domain models in fuzzy UML into a requirements ontology in description logic (DL) so that requirements verification can be automated with a popular DL reasoner such as Pellet. 展开更多
关键词 performance requirements efficiency evaluation func-tion description logic (DL) rationality.
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Systematic rationalization approach for multivariate correlated alarms based on interpretive structural modeling and Likert scale 被引量:5
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作者 高慧慧 徐圆 +2 位作者 顾祥柏 林晓勇 朱群雄 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第12期1987-1996,共10页
Alarm flood is one of the main problems in the alarm systems of industrial process. Alarm root-cause analysis and alarm prioritization are good for alarm flood reduction. This paper proposes a systematic rationalizati... Alarm flood is one of the main problems in the alarm systems of industrial process. Alarm root-cause analysis and alarm prioritization are good for alarm flood reduction. This paper proposes a systematic rationalization method for multivariate correlated alarms to realize the root cause analysis and alarm prioritization. An information fusion based interpretive structural model is constructed according to the data-driven partial correlation coefficient calculation and process knowledge modification. This hierarchical multi-layer model is helpful in abnormality propagation path identification and root-cause analysis. Revised Likert scale method is adopted to determine the alarm priority and reduce the blindness of alarm handling. As a case study, the Tennessee Eastman process is utilized to show the effectiveness and validity of proposed approach. Alarm system performance comparison shows that our rationalization methodology can reduce the alarm flood to some extent and improve the performance. 展开更多
关键词 Alarm rationalization Root-cause analysis Alarm priority Interpretive structural modeling Likert scale Tennessee Eastman process
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An osculatory rational interpolation method of model reduction in linear system 被引量:1
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作者 顾传青 张莺 《Journal of Shanghai University(English Edition)》 CAS 2007年第4期365-369,共5页
A theorem for osculatory rational interpolation was shown to establish a new criterion of interpolation. On the basis of this conclusion a practical algorithm was presented to get a reduction model of the linear syste... A theorem for osculatory rational interpolation was shown to establish a new criterion of interpolation. On the basis of this conclusion a practical algorithm was presented to get a reduction model of the linear systems. Some numerical examples were given to explain the result in this paper. 展开更多
关键词 osculatory rational interpolation criterion of interpolation ALGORITHM linear system model reduction
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Computational Analysis of Performance for Heterogeneous Integrated System with Test Automation 被引量:1
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作者 K.Krishna Mohan A.Srividya Ravikumar Gedela 《International Journal of Automation and computing》 EI 2007年第4期353-358,共6页
Heterogeneity is inevitable in enterprises due to their various input requirements. The usage of proprietary integration products results in the increased cost of enterprises. During the integration, the focus area ha... Heterogeneity is inevitable in enterprises due to their various input requirements. The usage of proprietary integration products results in the increased cost of enterprises. During the integration, the focus area has been found to often address only the functional requirements, while the non-functional requirements are side-stepped during the initial stages of a project. Moreover, the use of proprietary integration products and non-standards-based integration platform has given rise to an inflexible integration infrastructure resulting in adaptability concerns. Web services-based integration, based on open standards, is deemed to be the only feasible solution in such cases. This paper explains the performance analysis of enterprise integration in heterogeneous environments for the distributed and the transactional applications. The analysis presented in this paper is seen as a step towards making intelligent decisions well in advance when choosing the integration mechanism/products to address the functional as well as the non-functional requirements considering the future integration needs. 展开更多
关键词 Enterprise application integration reliability performance web services point-to-point IBM/rational platform service oriented architecture.
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Credit Rationing in Medium-small Enterprises Credit Market under Asymmetric Information 被引量:2
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作者 Jinke Wu Qingmei Tan 《Chinese Business Review》 2005年第2期17-22,共6页
Credit rationing has been an objective phenomenon in medium-small enterprises credit market of China. By analyzing the present situation of medium-small enterprises credit market of China, this study gives a new credi... Credit rationing has been an objective phenomenon in medium-small enterprises credit market of China. By analyzing the present situation of medium-small enterprises credit market of China, this study gives a new credit rationing model fitting medium-small enterprises credit market of China well. It has been showed in the empirical study that different factor has each different influence on medium-small enterprises credit market; further more, only the change of chastisement factor can make the medium-small enterprises credit market achieve whole success, but other factors can merely get integrant success even though under the most ideal condition. 展开更多
关键词 medium-sman enterprises credit market credit rationing asymmetric information
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Does driving-day-based tradable credit scheme outperform license plate rationing? Examination considering transaction cost
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作者 Zhen Lian Xiaobo Liu Wenbo Fan 《Journal of Modern Transportation》 2019年第3期198-210,共13页
This article models a novel driving-day-based tradable credit scheme (DD-TCS) to alleviate urban traffic congestion. In this model, car-using allowances (in terms of the number of days in a month, termed as "cred... This article models a novel driving-day-based tradable credit scheme (DD-TCS) to alleviate urban traffic congestion. In this model, car-using allowances (in terms of the number of days in a month, termed as "credit") are freely and uniformly allocated to all travellers, who are also allowed to trade them in a market according to his/her travel needs (e.g. driving more or fewer days than the free endowment). As opposed to most studies on TCS, this paper explicitly considers the transaction cost (e.g. infor-mation cost of finding potential traders) in the trading market. To assess the feasibility of DD-TCS, we compare it against the license plate rationing (LPR) scheme, which has been practically implemented in many cities such as Beijing and Chengdu in China. Taking the performance of LPR as a benchmark, we quantify the threshold values of the transaction cost in DD-TCS when the two schemes yield equivalent performance (in terms of the total gener-alized cost). In numerical studies, we also compare the DD-TCS and LPR with the no-action case and the congestion pricing case (representing the theoretical optimum). Results show that both DD-TCS and LPR outperform the no-action case under certain conditions. With small trans-action cost, DD-TCS may achieve a lower system cost that can be very close to the ideal optimum. In addition, parameter analysis shows that DD-TCS performs better than LPR in a wide range of transaction cost, where the threshold values appear to account for a considerable portion of the auto travel time. This implies that DD-TCS will be more appealing than LPR in practice because a transaction cost lower than the extremely large threshold values can be easily achieved for the trading market, e.g. via a mobile platform and modern communication techniques. 展开更多
关键词 Driving-day-based tradable CREDIT SCHEME License plate rationing Transaction cost Heterogeneous demand
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New Families of Rational Form Solitary Wave Solutions to (2+1)-Dimensional Broer-Kaup-Kupershmidt System*
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作者 WANGQi CHENYong +1 位作者 LIBiao ZHANGHong-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第5期769-774,共6页
Taking the (2+1)-dimensional Broer-Kaup-Kupershmidt system as a simple example, some families of rational form solitary wave solutions, triangular periodic wave solutions, and rational wave solutions are constructed b... Taking the (2+1)-dimensional Broer-Kaup-Kupershmidt system as a simple example, some families of rational form solitary wave solutions, triangular periodic wave solutions, and rational wave solutions are constructed by using the Riccati equation rational expansion method presented by us. The method can also be applied to solve more nonlinear partial differential equation or equations. 展开更多
关键词 Riccati equation rational expansion method (2+1) -dimensional Broer-Kaup-Kupershmidt system symbolic computation rational form solitary wave solutions
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New and More General Rational Formal Solutions to (2+1)-Dimensional Toda System
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作者 BAI Cheng-Lin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第5X期881-884,共4页
With the aid of computerized symbolic computation and Riccati equation rational expansion approach, some new and more general rational formal solutions to (2+1)-dimensional Toda system are obtained. The method used... With the aid of computerized symbolic computation and Riccati equation rational expansion approach, some new and more general rational formal solutions to (2+1)-dimensional Toda system are obtained. The method used here can also be applied to solve other nonlinear differential-difference equation or equations. 展开更多
关键词 Riccati equation rational expansion approach (2+1)-dimensional Toda system rational formal solutions
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STUDY ON EXACT ANALYTICAL SOLUTIONS FOR TWO SYSTEMS OF NONLINEAR EVOLUTION EQUATIONS
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作者 YAN Zhen-ya(闫振亚) +1 位作者 ZHANG Hong-qing(张鸿庆) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第8期925-934,共10页
The homogeneous balance method was improved and applied to two systems Of nonlinear evolution equations. As a result, several families of exact analytic solutions are derived by some new ansatzs. These solutions conta... The homogeneous balance method was improved and applied to two systems Of nonlinear evolution equations. As a result, several families of exact analytic solutions are derived by some new ansatzs. These solutions contain Wang's and Zhang's results and other new types of analytical solutions, such as rational fraction solutions and periodic solutions. The way can also be applied to solve more nonlinear partial differential equations. 展开更多
关键词 nonlinear evolution equations improved homogeneous balance method exact analytical solution solitary wave solution rational solution
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The Analysis of Credit Using and Rationing under Farmer 's Risk Attitudes Difference
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作者 Xinjun PANG Yunwu KUANG Xiaohong GONG 《Asian Agricultural Research》 2015年第4期24-32,共9页
This paper conducts a survey of 237 rural households in Zhangjiagang City,identifies farmers' risk attitude through ELCE method and problem design and empirically studies the relationship between risk attitudes an... This paper conducts a survey of 237 rural households in Zhangjiagang City,identifies farmers' risk attitude through ELCE method and problem design and empirically studies the relationship between risk attitudes and credit rationing by utilizing Probit and Logit model. The results show that farmers' risk attitude and credit rationing are in a significant positive correlation. The stronger farmers' risk aversion is,the more serious the demanded credit rationing becomes. Such risk attitude determines the risk cost and risk premium,thus affecting the credit behavior and credit rationing degree. In addition,distance between farmers' residence far the city and their land amount have a positive significant influence on credit rationing,while farmers' education level,income,family labor force have a negative significant effect on credit rationing. Based on these findings,the paper further analyzes the relationship between farmers' credit using and credit rationing as to farmers with different risk attitudes. Measures to relieve the farmer's credit rationing must be taken from government,financial institutions and farmers,respectively. 展开更多
关键词 RISK ATTITUDE CREDIT rationing RISK cost CREDIT us
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On the Solutions of Difference Equation Systems with Padovan Numbers
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作者 Yasin Yazlik D. Turgut Tollu Necati Taskara 《Applied Mathematics》 2013年第12期15-20,共6页
In this study, we investigate the form of the solutions of the following rational difference equation systems? , , such that their solutions are associated with Padovan numbers.
关键词 RATIONAL DIFFERENCE EQUATION system Padovan NUMBERS PLASTIC Number
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