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Multi-scenario Simulation of the Impact of Land Use Change on the Ecosystem Service Value in the Suzhou-Wuxi-Changzhou Metropolitan Area,China
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作者 WANG Bin HU Chunguang ZHANG Yushuo 《Chinese Geographical Science》 SCIE CSCD 2024年第1期79-92,共14页
As the most economically developed metropolitan area in China’s Yangtze River Delta,the rapid changing land use patterns of Suzhou-Wuxi-Changzhou(Su-Xi-Chang) metropolitan area have profound impacts on the ecosystem ... As the most economically developed metropolitan area in China’s Yangtze River Delta,the rapid changing land use patterns of Suzhou-Wuxi-Changzhou(Su-Xi-Chang) metropolitan area have profound impacts on the ecosystem service value(ESV).Based on the patterns of land use change and the ESV change in Su-Xi-Chang metropolitan area from 2000 to 2020,we set up four scenarios:natural development scenario,urban development scenario,arable land protection scenario and ecological protection scenario,and simulated the impact of land use changes on the ESV in these scenarios.The results showed that:1) the area of built-up land in the Su-XiChang metropolitan area increased significantly from 2000 to 2020,and the area of other types of land decreased.Arable land underwent the highest transfer-out area,and was primarily converted into built-up land.The total ESV of Su-Xi-Chang metropolitan area increased initially then declined from 2000–2020,and the value of almost all individual ecosystem services decreased.2) Population density,GDP per area,night lighting intensity,and road network density can negatively impact the ESV.3) The total ESV loss under the natural development and urban development scenarios was high,and the expansion of the built-up land and the drastic shrinkage of the arable land contributed to the ESV decline under both scenarios.The total ESV under arable land protection and ecological protection scenarios increases,and therefore these scenarios are suitable for future land use optimization in Su-Xi-Chang.This study could provide a certain reference for land use planning and allocation,and offer guidance for the rational allocation of land resources. 展开更多
关键词 multiple scenarios land use simulation ecosystem service value(ESV) Patch-Generating Land Use Simulation(PLUS)model Suzhou-Wuxi-Changzhou(Su-Xi-Chang)metropolitan area
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Multiple positive solutions for a class of nonlinear four-point boundary value problem with p-Laplacian 被引量:10
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作者 LI Xiang-feng 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第2期143-150,共8页
This paper deals with the existence of multiple positive solutions for a class of nonlinear singular four-point boundary value problem with p-Laplacian:{(φ(u′))′+a(t)f(u(t))=0, 0〈t〈1, αφ(u(... This paper deals with the existence of multiple positive solutions for a class of nonlinear singular four-point boundary value problem with p-Laplacian:{(φ(u′))′+a(t)f(u(t))=0, 0〈t〈1, αφ(u(0))-βφ(u′(ξ))=0,γφ(u(1))+δφ(u′(η))0,where φ(x) = |x|^p-2x,p 〉 1, a(t) may be singular at t = 0 and/or t = 1. By applying Leggett-Williams fixed point theorem and Schauder fixed point theorem, the sufficient conditions for the existence of multiple (at least three) positive solutions to the above four-point boundary value problem are provided. An example to illustrate the importance of the results obtained is also given. 展开更多
关键词 p-Laplacian operator multiple positive solution four-point singular boundary value problem fixed-point theorem.
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Existence of Multiple Positive Solutions for Fourth Order Two-point Boundary Value Problems 被引量:1
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作者 戚仕硕 《Northeastern Mathematical Journal》 CSCD 2002年第1期63-72,共10页
The present paper tackles two-point boundary value problems for fourth-order differential equations as follows:Several existence theorems on multiple positive solutions to the problems are obtained, and some examples ... The present paper tackles two-point boundary value problems for fourth-order differential equations as follows:Several existence theorems on multiple positive solutions to the problems are obtained, and some examples are given to show the validity of these results. 展开更多
关键词 existence theorem multiple positive solution fourth-order boundary value problem
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FAULT DETECTION FOR MULTIPLE-VALUED LOGIC CIRCUITS WITH FANOUT-FREE 被引量:1
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作者 PanZhongliang 《Journal of Electronics(China)》 2004年第5期376-383,共8页
The single fault and multiple fault detections for multiple-valued logic circuits are studied in this paper. Firstly, it is shown that the cardinality of optimal single fault test set for fanout-free m-valued circuits... The single fault and multiple fault detections for multiple-valued logic circuits are studied in this paper. Firstly, it is shown that the cardinality of optimal single fault test set for fanout-free m-valued circuits with n primary inputs is not more than n + 1, for linear tree circuits is two, and for multiplication modulo circuits is two if n is an odd number or if n is an even number and m > 3, where the optimal test set of a circuit has minimal number of test vectors. Secondly,it is indicated that the cardinality of optimal multiple fault test set for linear tree circuits with n primary inputs is 1 + [n/(m - 1)], for multiplication modulo circuits is n+ 1, for fanout-free circuits that consist of 2-input linear tree circuits and 2-input multiplication modulo circuits is not greater than n+ 1, where [x] denotes the smallest integer greater than or equal to x. Finally,the single fault location approaches of linear tree circuits and multiplication modulo circuits are presented, and all faults in the two types of circuits can be located by using a test set with n + 1 vectors. 展开更多
关键词 多值逻辑 数字电路 故障检测 单层错 多重故障
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ON MULTIPLE WIENER INTEGRAL EXPANSIONS FOR D'-VALUED NONLINEAR RANDOM FUNCTIONALS
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作者 吴奖伦 《Acta Mathematica Scientia》 SCIE CSCD 1993年第2期220-228,共9页
In this paper, the multiple stochastic integral with respect to a Wiener D'-process is defined. And also it is shown that for a D'-valued nonlinear random functional there exists a sequence of multiple integra... In this paper, the multiple stochastic integral with respect to a Wiener D'-process is defined. And also it is shown that for a D'-valued nonlinear random functional there exists a sequence of multiple integral kernels such that the nonlinear functional can be expanded by series of multiple Wiener integrals of the integral kernels with respect to the Wiener D'-process. 展开更多
关键词 valueD NONLINEAR RANDOM FUNCTIONALS ON multiple WIENER INTEGRAL EXPANSIONS FOR D ONB
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Estimating the expected value of multiple prospects in bidding blocks
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作者 Jun Li Xuebin Huang 《Energy Geoscience》 2022年第3期263-269,共7页
In recent years,China has accelerated the reform of its oil and gas management system,especially in competitive transfer of mining rights.Evaluating the expected value(EV)of lease blocks is crucial for the bidding dec... In recent years,China has accelerated the reform of its oil and gas management system,especially in competitive transfer of mining rights.Evaluating the expected value(EV)of lease blocks is crucial for the bidding decision of oil companies.When bidding for a block with several individual prospects,the simple addition of each prospect EV usually leads to overly high and optimistic resource volume and value estimates.For the assessment of the EV of a multi-prospect block,two factors should be considered.Firstly,the geological setting of the prospects,including their relative spatial relationship,their chance of geological success,their resources and their geological dependency,etc.The second factor is the exploration strategy of oil companies,concerned with the dry hole tolerance,the committed wells and the drilling priorities for the prospects,etc.A probabilistic method to assess the EV of a multi-prospect block is proposed,which proves to be favorable for formulating a bidding strategy for oil companies.In addition,a case study on two specific blocks with several prospects is presented to illustrate the effect of the above mentioned factors on the EV. 展开更多
关键词 Expected value(EV) multiple prospects Bidding block Probabilistic method
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MULTIPLE POSITIVE SOLUTIONS OF A SINGULAR (n-1,1) CONJUGATE BOUNDARY VALUE PROBLEM WITH DELAY 被引量:2
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作者 Weng Peixuan\ Tian YanlingDept. of Math.,South China Normal Univ.,Guangzhou 51 0 631 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2000年第2期128-136,共9页
This paper discusses the singular ( n\|1,1 ) conjugate boundary value problem as follows by using a fixed point index theorem in cones[HL(2:1,Z;2,Z]u (n) (t)+a(t)f(u(w(t)))=0,(0<t<1), u(t)=φ(t),(-τ≤t&l... This paper discusses the singular ( n\|1,1 ) conjugate boundary value problem as follows by using a fixed point index theorem in cones[HL(2:1,Z;2,Z]u (n) (t)+a(t)f(u(w(t)))=0,(0<t<1), u(t)=φ(t),(-τ≤t<0), u (j) (0)=u(1)=0,(1≤j≤n-2).Effort is devoted to give some sufficient conditions for which the equation has at least two positive solutions.An example to illustrate the application of this theorem is given. [FQ(6*2。39,X-W] 展开更多
关键词 Conjugate boundary value problem functional differential equation multiple positive solution.Keywords:Conjugateboundaryvalueproblem functionaldifferentialequation multiplepositivesolu-tion.
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The Biorthogonality of Multiple Vector-valued Bivariate Wavelet Packets
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作者 CHEN Shao-dong HUANG Na 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第2期208-213,共6页
The notion of a sort of biorthogonal multiple vector-valued bivariate wavelet packets,which are associated with a quantity dilation matrix,is introduced.The biorthogonality property of the multiple vector-valued wavel... The notion of a sort of biorthogonal multiple vector-valued bivariate wavelet packets,which are associated with a quantity dilation matrix,is introduced.The biorthogonality property of the multiple vector-valued wavelet packets in higher dimensions is studied by means of Fourier transform and integral transform biorthogonality formulas concerning these wavelet packets are obtained. 展开更多
关键词 BIVARIATE multiple vector-valued multiresolution analysis multiple vectorvalued scaling function multiple vector-valued wavelet packets biorthogonality
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SPECTRAL ANALYSIS OF SOME INDEPENDENCES OF MULTIPLE-VALUED LOGICAL FUNCTIONS ON THEIR VARIABLES
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作者 武传坤 《Journal of Electronics(China)》 1993年第3期217-226,共10页
There are many kinds of special relationships between multiple-valued logical func-tions and their variables, and they are difficult to be judged from their expressions. In thispaper, some sufficient and necessary con... There are many kinds of special relationships between multiple-valued logical func-tions and their variables, and they are difficult to be judged from their expressions. In thispaper, some sufficient and necessary conditions of the independence and statistical independenceof multiple-valued logical functions on their variables are given. Some conditions of algebraicindependence of multiple-valued logical functions on some of their variables and the way to de-generate a function to the greatest extent are proposed, and some applications of these resultsare indicated. All the results are studied by using Chrestenson spectral techniques. 展开更多
关键词 multiple-valued logical function Chrestenson SPECTRUM DEGENERATION Correlationimmunity Linear code
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CIRCUIT TESTABLE DESIGN AND UNIVERSAL TEST SETS FOR MULTIPLE-VALUED LOGIC FUNCTIONS
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作者 Pan Zhongliang 《Journal of Electronics(China)》 2007年第1期138-144,共7页
The circuit testable realizations of multiple-valued functions are studied in this letter. First of all,it is shown that one vector detects all skew faults in multiplication modulo circuits or in addi-tion modulo circ... The circuit testable realizations of multiple-valued functions are studied in this letter. First of all,it is shown that one vector detects all skew faults in multiplication modulo circuits or in addi-tion modulo circuits,and n+1 vectors detect all skew faults in the circuit realization of multiple-valued functions with n inputs. Secondly,min(max) bridging fault test sets with n+2 vectors are pre-sented for the circuit realizations of multiple-valued logic functions. Finally,a tree structure is used instead of cascade structure to reduce the delay in the circuit realization,it is shown that three vec-tors are sufficient to detect all single stuck-at faults in the tree structure realization of multiple-valued logic functions. 展开更多
关键词 电路设计 可检测性设计 多值逻辑功能 信号故障 通用测试装置
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A two-parameter multiple shooting method and its application to the natural vibrations of non-prismatic multi-segment beams
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作者 R.HOŁUBOWSKI K.JARCZEWSKA 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第12期2243-2252,共10页
This paper presents an enhanced version of the standard shooting method that enables problems with two unknown parameters to be solved.A novel approach is applied to the analysis of the natural vibrations of Euler-Ber... This paper presents an enhanced version of the standard shooting method that enables problems with two unknown parameters to be solved.A novel approach is applied to the analysis of the natural vibrations of Euler-Bernoulli beams.The proposed algorithm,named as two-parameter multiple shooting method,is a new powerful numerical tool for calculating the natural frequencies and modes of multi-segment prismatic and non-prismatic beams with different boundary conditions.The impact of the axial force and additional point masses is also taken into account.Due to the fact that the method is based directly on the fourth-order ordinary differential equation,the structures do not have to be divided into many small elements to obtain an accurate enough solution,even though the geometry is very complex.To verify the proposed method,three different examples are considered,i.e.,a three-segment non-prismatic beam,a prismatic column subject to non-uniformly distributed compressive loads,and a two-segment beam with an additional point mass.Numerical analyses are carried out with the software MATHEMATICA.The results are compared with the solutions computed by the commercial finite element program SOFiSTiK.Good agreement is achieved,which confirms the correctness and high effectiveness of the formulated algorithm. 展开更多
关键词 two-parameter multiple shooting method two-point boundary value problem natural vibration non-prismatic beam multi-segment beam
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Research on Fuzzy Multiple Attribute Route Evaluation Decision Method
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作者 Geng Yu Qing Liu 《World Journal of Engineering and Technology》 2019年第2期65-72,共8页
The route evaluation is an important basis for airlines to make route decisions. In order to solve the fuzzy multiple attribute route decision problem, route attribute weight was completely unknown, and the route eval... The route evaluation is an important basis for airlines to make route decisions. In order to solve the fuzzy multiple attribute route decision problem, route attribute weight was completely unknown, and the route evaluation fuzzy language information was given, the fuzzy language and preference information were converted into trapezoidal fuzzy numbers. A programming model was constructed by minimizing the total deviation between trapezoidal fuzzy numbers to determining the weight of each attribute in the route decision, By weighting the average of the route attribute value and the weights value, compared the expected value of fuzzy comprehensive evaluation for each route, and ranking alternatives by using the expected value operator of fuzzy variable. Finally, a numerical example was used to illustrate the proposed method. The results show that the method can be used by air-lines to solve multiple attribute route decision problems with unknown weights, and the method is scientific and effective. 展开更多
关键词 ROUTE DECISION FUZZY Language multiple ATTRIBUTE DECISION MAKING Trapezoidal FUZZY Number EXPECTED value
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Existence and Multiplicity of Positive Solutions for a Singular Third-Order Three-Point Boundary Value Problem with a Parameter
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作者 Xingfang Feng Hanying Feng 《Journal of Applied Mathematics and Physics》 2022年第4期1146-1157,共12页
In this paper, we investigate the existence of positive solutions for a singular third-order three-point boundary value problem with a parameter. By using fixed point index theory, some existence, multiplicity and non... In this paper, we investigate the existence of positive solutions for a singular third-order three-point boundary value problem with a parameter. By using fixed point index theory, some existence, multiplicity and nonexistence results for positive solutions are derived in terms of different values of λ. 展开更多
关键词 Three-Point Boundary value Problem Fixed Point Index Positive Solution EXISTENCE multiplICITY
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Analysis and Research on the Functional Value and Development Opportunities of Hainan National Breeding and Multiplication
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作者 Guanming CHEN Yaqiong LIN +1 位作者 Jinsong LI Liping WANG 《Asian Agricultural Research》 2013年第6期31-33,143,共4页
To further specify significance and development orientation of Hainan National Breeding and Multiplication ( hereinafter referred to as HNBM) ,such concepts as value engineering,industrial cluster and regional economy... To further specify significance and development orientation of Hainan National Breeding and Multiplication ( hereinafter referred to as HNBM) ,such concepts as value engineering,industrial cluster and regional economy were introduced by analyzing its properties and interpreting relevant policies,its functions,value and development opportunities were analyzed from multiple perspectives. According to the comprehensive analysis,HNBM concerns national core political and economic benefits in strategic and fundamental sense,which is a result of powerful comprehensive functions of HNBM and need of modern agricultural development. In addition,HNBM has a bottleneck in the development of industrial cluster. Only co-promoted by the province and the ministry,and by applying top-level design,breaking the conditionality,integrating and optimizing existing resources,HNBM will be constructed into a high-new seed industry center. 展开更多
关键词 HAINAN NATIONAL BREEDING multiplICATION ( HNBM) VA
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Precise integration method for a class of singular two-point boundary value problems 被引量:2
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作者 Wen-Zhi Zhang Pei-Yan Huang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2013年第2期233-240,共8页
In this paper we present a precise integration method based on high order multiple perturbation method and reduction method for solving a class of singular twopoint boundary value problems.Firstly,by employing the met... In this paper we present a precise integration method based on high order multiple perturbation method and reduction method for solving a class of singular twopoint boundary value problems.Firstly,by employing the method of variable coefficient dimensional expanding,the non-homogeneous ordinary differential equations(ODEs) are transformed into homogeneous ODEs.Then the interval is divided evenly,and the transfer matrix in every subinterval is worked out using the high order multiple perturbation method,and a set of algebraic equations is given in the form of matrix by the precise integration relation for each segment,which is worked out by the reduction method.Finally numerical examples are elaboratedd to validate the present method. 展开更多
关键词 Singular two point boundary value problem Precise integration method High order multiple perturbation method Reduction method
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THE DISTRIBUTION OF VALUES OF TAYLOR SERIES 被引量:1
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作者 余家荣 《Acta Mathematica Scientia》 SCIE CSCD 2012年第5期1719-1726,共8页
Clarify some classical results and their proofs on the distribution of values of simple Taylor series and extend them to multiple Taylor series.
关键词 simple and multiple Taylor series distribution of values
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Carbon stock and sink economic values of forest ecosystem in the forest industry region of Heilongjiang Province, China 被引量:1
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作者 Mingjuan Li 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第3期875-882,共8页
The values of forest carbon stock (CSV) and carbon sink (COV) are important topics in the global carbon cycle. We quantitatively analyzed the factors affecting changes in both for forest ecosystem in 2000−2015. With m... The values of forest carbon stock (CSV) and carbon sink (COV) are important topics in the global carbon cycle. We quantitatively analyzed the factors affecting changes in both for forest ecosystem in 2000−2015. With multiple linear stepwise regression analysis, we obtained the factors that had a significant impact on changes of CSV and COV, and then the impacts of these variables on CSV and COV were used for further quantitative analysis using the vector autoregressive model. Our results indicated that both stand age and afforestation area positively affect CSV and COV;however, the forest enterprise gross output value negatively affects CSV. Stand age has the largest long-term cumulative impact on CSV and COV, reaching 40.4% and 9.8%, respectively. The impact of enterprise gross output value and afforestation area on CSV and COV is the smallest, reaching 4.0% and 0.3%, respectively. 展开更多
关键词 Carbon stock value Carbon sink value multiple regression analysis VAR model
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Consistency and Stability Issues in the Numerical Integration of the First and Second Order Initial Value Problem 被引量:1
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作者 Isaac Fried 《Applied Mathematics》 2019年第8期676-690,共15页
In this note we consider some basic, yet unusual, issues pertaining to the accuracy and stability of numerical integration methods to follow the solution of first order and second order initial value problems (IVP). I... In this note we consider some basic, yet unusual, issues pertaining to the accuracy and stability of numerical integration methods to follow the solution of first order and second order initial value problems (IVP). Included are remarks on multiple solutions, multi-step methods, effect of initial value perturbations, as well as slowing and advancing the computed motion in second order problems. 展开更多
关键词 INITIAL value Problems Numerical Integration CONSISTENCY STABILITY multiple Solutions Sensitivity to INITIAL Conditions Slowing and Advancing the COMPUTED Motion
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Parker Test for Heteroskedasticity Based on Sample Fitted Values 被引量:1
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作者 Jingming Jiang Guangming Deng 《Open Journal of Statistics》 2021年第3期400-408,共9页
<p> <span style="font-family:Verdana;">To address the drawbacks of the traditional Parker test in multivariate linear</span><span style="font-family:;" "=""> ... <p> <span style="font-family:Verdana;">To address the drawbacks of the traditional Parker test in multivariate linear</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">models:</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">the process is cumbersome and computationally intensive,</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">we propose a new heteroscedasticity test.</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">A new heteroskedasticity test is proposed using the fitted values of the samples as new explanatory variables, reconstructing the regression model, and giving a new heteroskedasticity test based on the significance test of the coefficients, it is also compared with the existing Parker test which is improved using the principal component idea. Numerical simulations and empirical analyses show that the improved Parker test with the fitted values of the samples proposed in this paper is superior.</span> </p> 展开更多
关键词 multiple Linear Regression Model Parker Test Fitted values Heteroskedasticity Test
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AN ANALYSIS ON LOCATION FACTORS AFFECTING THE SPATIAL DISTRIBUTION OF SHANGHAI LAND VALUES
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作者 杜德斌 徐建刚 《Chinese Geographical Science》 SCIE CSCD 1998年第4期48-55,共0页
I.INTRODUCTIONThereisaclosecorelationbetweenthelocationofalandparcelanditsvalue.Arealestateexpertoncestatedt... I.INTRODUCTIONThereisaclosecorelationbetweenthelocationofalandparcelanditsvalue.Arealestateexpertoncestatedthatthefactorsdete... 展开更多
关键词 SHANGHAI LAND valueS LOCATION FACTORS multiple regression ANALYSIS GIS
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