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The effects of land market development on economic growth: an empirical analysis based on Chinese panel data,1999-2005 被引量:1
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作者 YANG Hong-mei 《Ecological Economy》 2010年第1期88-95,共8页
Optimized land resources allocation is important for economic growth because land is one of the basic elements for economic development. And urban land resources allocation has had an increasingly important influence ... Optimized land resources allocation is important for economic growth because land is one of the basic elements for economic development. And urban land resources allocation has had an increasingly important influence since the Chinese socialist market economy system was established. This paper estimates the production function of both the secondary and the tertiary industries of China's 31 provinces, autonomous regions and municipalities directly under the central government through an analysis of the panel data of the total output value of the secondary and the tertiary industries, invested capital, invested labor jorces and the land market-jeatured management of the above-mentioned regions during the period of 1999-2005. and examines the positive influence of the above- mentioned factors on regional economic output, This study concludes that urban economic output is positively related with the level of urban land resources market-featured management, since the rate of economic growth of those regions approximates 14. 7% under the condition of urban land market running during the period of 1999-2005. 展开更多
关键词 Land market Economic growth panel data Regional difference
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Finite Difference-Peridynamic Differential Operator for Solving Transient Heat Conduction Problems
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作者 Chunlei Ruan Cengceng Dong +2 位作者 Zeyue Zhang Boyu Chen Zhijun Liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第9期2707-2728,共22页
Transient heat conduction problems widely exist in engineering.In previous work on the peridynamic differential operator(PDDO)method for solving such problems,both time and spatial derivatives were discretized using t... Transient heat conduction problems widely exist in engineering.In previous work on the peridynamic differential operator(PDDO)method for solving such problems,both time and spatial derivatives were discretized using the PDDO method,resulting in increased complexity and programming difficulty.In this work,the forward difference formula,the backward difference formula,and the centered difference formula are used to discretize the time derivative,while the PDDO method is used to discretize the spatial derivative.Three new schemes for solving transient heat conduction equations have been developed,namely,the forward-in-time and PDDO in space(FT-PDDO)scheme,the backward-in-time and PDDO in space(BT-PDDO)scheme,and the central-in-time and PDDO in space(CT-PDDO)scheme.The stability and convergence of these schemes are analyzed using the Fourier method and Taylor’s theorem.Results show that the FT-PDDO scheme is conditionally stable,whereas the BT-PDDO and CT-PDDO schemes are unconditionally stable.The stability conditions for the FT-PDDO scheme are less stringent than those of the explicit finite element method and explicit finite difference method.The convergence rate in space for these three methods is two.These constructed schemes are applied to solve one-dimensional and two-dimensional transient heat conduction problems.The accuracy and validity of the schemes are verified by comparison with analytical solutions. 展开更多
关键词 Peridynamic differential operator finite difference method STABILITY transient heat conduction problem
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Fault Diagnosis Method of Rolling Bearing Based on ESGMD-CC and AFSA-ELM
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作者 Jiajie He Fuzheng Liu +3 位作者 Xiangyi Geng Xifeng Liang Faye Zhang Mingshun Jiang 《Structural Durability & Health Monitoring》 EI 2024年第1期37-54,共18页
Incomplete fault signal characteristics and ease of noise contamination are issues with the current rolling bearing early fault diagnostic methods,making it challenging to ensure the fault diagnosis accuracy and relia... Incomplete fault signal characteristics and ease of noise contamination are issues with the current rolling bearing early fault diagnostic methods,making it challenging to ensure the fault diagnosis accuracy and reliability.A novel approach integrating enhanced Symplectic geometry mode decomposition with cosine difference limitation and calculus operator(ESGMD-CC)and artificial fish swarm algorithm(AFSA)optimized extreme learning machine(ELM)is proposed in this paper to enhance the extraction capability of fault features and thus improve the accuracy of fault diagnosis.Firstly,SGMD decomposes the raw vibration signal into multiple Symplectic geometry components(SGCs).Secondly,the iterations are reset by the cosine difference limitation to effectively separate the redundant components from the representative components.Additionally,the calculus operator is performed to strengthen weak fault features and make them easier to extract,and the singular value decomposition(SVD)weighted by power spectrum entropy(PSE)can be utilized as the sample feature representation.Finally,AFSA iteratively optimized ELM is adopted as the optimized classifier for fault identification.The superior performance of the proposed method has been validated by various experiments. 展开更多
关键词 Symplectic geometry mode decomposition calculus operator cosine difference limitation fault diagnosis AFSAELM model
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LEIBNIZ′FORMULA OF GENERALIZED DIFFERENCE WITH RESPECT TO A CLASS OF DIFFERENTIAL OPERATORS AND RECURRENCE FORMULA OF THEIR GREEN′S FUNCTION 被引量:1
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作者 许跃生 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1984年第3期1359-1364,共6页
In this paper, Leibniz' formula of generalized divided difference with respect to a class of differential operators whose basic sets of solutions have power form, is considered. The recurrence formula of Green fun... In this paper, Leibniz' formula of generalized divided difference with respect to a class of differential operators whose basic sets of solutions have power form, is considered. The recurrence formula of Green function about the operators is also given. 展开更多
关键词 LEIBNIZ S FUNCTIon FORMULA OF GENERALIZED DIFFERENCE WITH RESPECT TO A CLASS OF differentIAL OPERATORS AND RECURRENCE FORMULA OF theIR GREEN
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NOTES ON THE SPECTRAL PROPERTIES OF THE WEIGHTED MEAN DIFFERENCE OPERATOR G(u,v;?) OVER THE SEQUENCE SPACE ?_1
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作者 Vatan KARAKAYA Ezgi ERDOGAN 《Acta Mathematica Scientia》 SCIE CSCD 2016年第2期477-486,共10页
In the study by Baliarsingh and Dutta [Internat. J.Anal., Vol.2014(2014), Article ID 786437], the authors computed the spectrum and the fine spectrum of the product operator G (u, v; A) over the sequence space e1.... In the study by Baliarsingh and Dutta [Internat. J.Anal., Vol.2014(2014), Article ID 786437], the authors computed the spectrum and the fine spectrum of the product operator G (u, v; A) over the sequence space e1. The product operator G (u, v; △) over l1 is defined by (G(u,v;△)x)k=^k∑i=0ukvi(xi- xi-1) with xk = 0 for all k 〈 0, where x = (xk)∈e1,and u and v axe either constant or strictly decreasing sequences of positive real numbers satisfying certain conditions. In this article we give some improvements of the computation of the spectrum of the operator G (u, v; △) on the sequence space gl. 展开更多
关键词 Spectrum of an operator weighted mean difference operator sequence space
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Trajectory Controllability of Nonlinear Integro-Differential System—An Analytical and a Numerical Estimations
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作者 Dimplekumar Chalishajar Heena Chalishajar John David 《Applied Mathematics》 2012年第11期1729-1738,共10页
A stronger concept of complete (exact) controllability which we call Trajectory Controllability is introduced in this paper. We study the Trajectory Controllability of an abstract nonlinear integro-differential system... A stronger concept of complete (exact) controllability which we call Trajectory Controllability is introduced in this paper. We study the Trajectory Controllability of an abstract nonlinear integro-differential system in the finite and infinite dimensional space setting. We will then discuss how approximations to these problems can be found computationally using finite difference methods and optimization. Examples will be presented in one, two and three dimensions. 展开更多
关键词 Trajectory ConTROLLABILITY MOnoTonE Operator theory Set VALUED Function LIPSCHITZ ConTINUITY Finite Difference Optimization
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The Relationship between the Performance of Listed Companies in Pharmaceutical Manufacturing and Inventory Turnover, Operating Rate
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作者 Yutong Hai 《经济管理学刊(中英文版)》 2019年第1期9-21,共13页
As an important part of the pharmaceutical industry, the pharmaceutical manufacturing industry is always at the battlefield of the international public health and health industry. At the same time, as a basic and stra... As an important part of the pharmaceutical industry, the pharmaceutical manufacturing industry is always at the battlefield of the international public health and health industry. At the same time, as a basic and strategic sub-industry in China's manufacturing industry, the medical manufacturing industry closely related to people’s livelihood which is not only related to social Responsibility but also plays a key role in China's economy today. For the Chinese people, the new medical reforms and the irreversible aging of the population have increased the nation’s total expenditure on health care. From January to October 2017, the pharmaceutical industry’s main business income was RMB 2,410.29 billion, a year-on-year increase of 13.10%. This is a 4.50 percentage point higher than the 10.30% growth rate in 2016. However, even if the circumstance of this industry is getting better, high growth also has a drag on the national health insurance system and the standard of living of the people. This article chooses to analyze the financial and operating-level factors of China's pharmaceutical manufacturing listed companies such as Inventory turnover rate and operating rate. Study the impact on the performance of China's pharmaceutical manufacturing listed companies. The results of the study will fill gaps in the research of this industry and help pharmaceutical manufacturing listed companies choose the right capital size, liabilities, and expansion strategies, and more effectively absorb the current development dividends of China’s “four new economy”, and use them rationally and effectively. Markets and complex and limited capital and resources of enterprises, as China's industry benchmarks continue to guide the rapid growth of the market. on the other hand, to help investor the empirical point of view better choice of investment targets. This paper uses data from 2007-2016 for randomly selecting 19 companies from 118 medical manufacturing listed companies classified by China Securities Regulatory Commission. After dealing with panel data, multiple inspections are performed on panel data. To avoid the deviation from the actual level of the regression results, the panel-corrected standard deviation model was used to derive the relationship between the operating-level factors of pharmaceutical manufacturing listed companies and their performance. The results of the study indicate that there is a positive correlation between Inventory turnover rate, operating rate and performance, which fills the domestic empirical research on this issue. This area of industry company performance is blank. 展开更多
关键词 PHARMACEUTICAL Manufacturing LISTED Companies CORPORATIon PERFORMANCE panel Data Inventory TURnoVER Operating Rate of Return
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Research on the Optimization Design of Intersections for Safe Operation of Large Trucks
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作者 Yujie Bao Pincheng Wang Yuhang Li 《Journal of Information Hiding and Privacy Protection》 2020年第3期143-154,共12页
When big trucks are running at urban road intersections,they are easy to interfere with other motor vehicles,and the turning big trucks are easy to have conflicts with non-motor vehicles and pedestrians,which will aff... When big trucks are running at urban road intersections,they are easy to interfere with other motor vehicles,and the turning big trucks are easy to have conflicts with non-motor vehicles and pedestrians,which will affect the safety of intersections.This paper first studied the intersection of trucks to the running trajectory,on this basis,through the establishment of mathematical model analysis of large truck steering conditions inside the wheel,and the influence of blind area to the driver.In the research of intersection safety design,the safety design is divided into three parts:Entrance road,internal operation and signal control.At the same time,the design method of the entrance road,the interior of the intersection and the signal control is given,which improves the safety of the truck driving at the intersection.Finally,the intersection of Jungong road and Zhoujiazui road in Yangpu district of Shanghai was selected as a case,and the optimal design of the intersection for large trucks was carried out through the investigation and analysis of actual data.The evaluation and analysis were carried out by using the multi-index matter-element model.The results show that the comprehensive safety correlation degree of the intersection is reduced to 0.42,and the safety level of is improved by one level. 展开更多
关键词 Large truck city road intersection safety design safety operation inner wheel difference blind area
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COMPACT DIFFERENCES OF COMPOSITION OPERATORS ON HOLOMORPHIC FUNCTION SPACES IN THE UNIT BALL 被引量:6
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作者 江良英 欧阳才衡 《Acta Mathematica Scientia》 SCIE CSCD 2011年第5期1679-1693,共15页
We find a lower bound for the essential norm of the difference of two composition operators acting on H 2(BN ) or As2 (BN ) (s 1). This result plays an important role in proving a necessary and sufficient condit... We find a lower bound for the essential norm of the difference of two composition operators acting on H 2(BN ) or As2 (BN ) (s 1). This result plays an important role in proving a necessary and sufficient condition for the difference of linear fractional composition operators to be compact, which answers a question posed by MacCluer and Weir in 2005. 展开更多
关键词 composition operators Hardy space Bergman spaces compact differences
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Discrete Fractional Lagrange Equations of Nonconservative Systems 被引量:3
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作者 SONG Chuanjing ZHANG Yi 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2019年第1期175-180,共6页
In order to study discrete nonconservative system,Hamilton's principle within fractional difference operators of Riemann-Liouville type is given. Discrete Lagrange equations of the nonconservative system as well a... In order to study discrete nonconservative system,Hamilton's principle within fractional difference operators of Riemann-Liouville type is given. Discrete Lagrange equations of the nonconservative system as well as the nonconservative system with dynamic constraint are established within fractional difference operators of Riemann-Liouville type from the view of time scales. Firstly,time scale calculus and fractional calculus are reviewed.Secondly,with the help of the properties of time scale calculus,discrete Lagrange equation of the nonconservative system within fractional difference operators of Riemann-Liouville type is presented. Thirdly,using the Lagrange multipliers,discrete Lagrange equation of the nonconservative system with dynamic constraint is also established.Then two special cases are discussed. Finally,two examples are devoted to illustrate the results. 展开更多
关键词 DISCRETE LAGRANGE equation time scale FRACTIonAL DIFFERENCE OPERATOR noNConSERVATIVE system
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ENTIRE FUNCTIONS SHARING ONE SMALL FUNCTION CM WITH THEIR SHIFTS AND DIFFERENCE OPERATORS 被引量:3
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作者 崔宁 陈宗煊 《Acta Mathematica Scientia》 SCIE CSCD 2017年第3期786-798,共13页
In this article, we mainly devote to proving uniqueness results for entire functionssharing one small function CM with their shift and difference operator simultaneously. Letf(z) be a nonconstant entire function of ... In this article, we mainly devote to proving uniqueness results for entire functionssharing one small function CM with their shift and difference operator simultaneously. Letf(z) be a nonconstant entire function of finite order, c be a nonzero finite complex constant, and n be a positive integer. If f(z), f(z+c), and △n cf(z) share 0 CM, then f(z+c)≡Af(z), where A(≠0) is a complex constant. Moreover, let a(z), b(z)( O) ∈ S(f) be periodic entire functions with period c and if f(z) - a(z), f(z + c) - a(z), △cn f(z) - b(z) share 0 CM, then f(z + c) ≡ f(z). 展开更多
关键词 Entire function SHIFTS difference operators shared values
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Properties for Solutions of Nonlinear Functional Difference Equations 被引量:2
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作者 DUANMU Lian-xi 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2005年第3期258-264,共7页
In this paper, some sufficient and necessary conditions are established for the oscillatory of solutions for nonlinear functional difference equations, which extend and improve some corresponding results obtained and ... In this paper, some sufficient and necessary conditions are established for the oscillatory of solutions for nonlinear functional difference equations, which extend and improve some corresponding results obtained and are discrete analogues of the corresponding results for the continuous version. 展开更多
关键词 functional difference equation OSCILLATIon increasing operator fixed point theorem
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A NOTE ON VALUE DISTRIBUTION OF DIFFERENCE POLYNOMIALS OF MEROMORPHIC FUNCTIONS 被引量:2
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作者 姚丽萍 陈宗煊 《Acta Mathematica Scientia》 SCIE CSCD 2014年第6期1826-1834,共9页
In this paper, we investigate the value distribution of the difference counterpart △f(z)- af(z)^n of f′(z)- af(z)^n and obtain an almost direct difference analogue of result of Hayman.
关键词 shift difference operator order
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Monopulse instantaneous 3D imaging for wideband radar system 被引量:3
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作者 LI Yuhan QI Wei +2 位作者 DENG Zhenmiao FU Maozhong ZHANG Yunjian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第1期53-67,共15页
To avoid the complicated motion compensation in interferometric inverse synthetic aperture(InISAR)and achieve realtime three-dimensional(3 D)imaging,a novel approach for 3 D imaging of the target only using a single e... To avoid the complicated motion compensation in interferometric inverse synthetic aperture(InISAR)and achieve realtime three-dimensional(3 D)imaging,a novel approach for 3 D imaging of the target only using a single echo is presented.This method is based on an isolated scatterer model assumption,thus the scatterers in the beam can be extracted individually.The radial range of each scatterer is estimated by the maximal likelihood estimation.Then,the horizontal and vertical wave path difference is derived by using the phase comparison technology for each scatterer,respectively.Finally,by utilizing the relationship among the 3 D coordinates,the radial range,the horizontal and vertical wave path difference,the 3 D image of the target can be reconstructed.The reconstructed image is free from the limitation in InISAR that the image plane depends on the target's own motions and on its relative position with respect to the radar.Furthermore,a phase ambiguity resolution method is adopted to ensure the success of the 3 D imaging when phase ambiguity occurs.It can be noted that the proposed phase ambiguity resolution method only uses one antenna pair and does not require a priori knowledge,whereas the existing phase ambiguity methods may require two or more antenna pairs or a priori knowledge for phase unwarping.To evaluate the performance of the proposed method,the theoretical analyses on estimation accuracy are presented and the simulations in various scenarios are also carried out. 展开更多
关键词 cross-correlation operation phase ambiguity resolution wave path difference estimation monopulse three-dimensional(3D)imaging
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Mutual transformations between the P–Q, Q–P, and generalized Weyl ordering of operators
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作者 徐兴磊 李洪奇 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第3期119-122,共4页
Based on the generalized Weyl quantization scheme, which relies on the generalized Wigner operator Ok (p, q) with a real k parameter and can unify the P-Q, Q-P, and Weyl ordering of operators in k = 1, - 1,0, respec... Based on the generalized Weyl quantization scheme, which relies on the generalized Wigner operator Ok (p, q) with a real k parameter and can unify the P-Q, Q-P, and Weyl ordering of operators in k = 1, - 1,0, respectively, we find the mutual transformations between 6 (p - P) (q - Q), (q - Q) 3 (p - P), and (p, q), which are, respectively, the integration kernels of the P-Q, Q-P, and generalized Weyl quantization schemes. The mutual transformations provide us with a new approach to deriving the Wigner function of quantum states. The - and - ordered forms of (p, q) are also derived, which helps us to put the operators into their - and - ordering, respectively. 展开更多
关键词 generalized Wigner operator generalized Weyl quantization scheme different operator orderingrules mutual transformation
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Multigrid Solution of an Elliptic Fredholm Partial Integro-Differential Equation with a Hilbert-Schmidt Integral Operator
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作者 Duncan Kioi Gathungu Alfio Borzì 《Applied Mathematics》 2017年第7期967-986,共20页
An efficient multigrid finite-differences scheme for solving elliptic Fredholm partial integro-differential equations (PIDE) is discussed. This scheme combines a second-order accurate finite difference discretization ... An efficient multigrid finite-differences scheme for solving elliptic Fredholm partial integro-differential equations (PIDE) is discussed. This scheme combines a second-order accurate finite difference discretization of the PIDE problem with a multigrid scheme that includes a fast multilevel integration of the Fredholm operator allowing the fast solution of the PIDE problem. Theoretical estimates of second-order accuracy and results of local Fourier analysis of convergence of the proposed multigrid scheme are presented. Results of numerical experiments validate these estimates and demonstrate optimal computational complexity of the proposed framework. 展开更多
关键词 ELLIPTIC Problems FREDHOLM OPERATOR MULTIGRID SCHEMES Finite DIFFERENCES Numerical Analysis
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On Some Class of n-Normed Generalized Difference Sequences Related to l_p-Space
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作者 Binod Chandra Tripathy Inder Kumar Rana Stuti Borgohain 《Analysis in Theory and Applications》 2014年第2期214-223,共10页
In this paper, we introduce the class of n-normed generalized difference sequences related to lp-space. Some properties of this sequence space like solidness, symmetricity, convergence-free etc. are studied. We obtain... In this paper, we introduce the class of n-normed generalized difference sequences related to lp-space. Some properties of this sequence space like solidness, symmetricity, convergence-free etc. are studied. We obtain some inclusion relations involving this sequence space. 展开更多
关键词 Generalized difference operator n-norm n-Banach space symmetricity solidness convergence free completeness.
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Optimization of the seismic processing phase-shift plus finite-difference migration operator based on a hybrid genetic and simulated annealing algorithm 被引量:2
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作者 Luo Renze Huang Yuanyi +2 位作者 Liang Xianghao Luo Jun Cao Ying 《Petroleum Science》 SCIE CAS CSCD 2013年第2期190-194,共5页
Although the phase-shift seismic processing method has characteristics of high accuracy, good stability, high efficiency, and high-dip imaging, it is not able to adapt to strong lateral velocity variation. To overcome... Although the phase-shift seismic processing method has characteristics of high accuracy, good stability, high efficiency, and high-dip imaging, it is not able to adapt to strong lateral velocity variation. To overcome this defect, a finite-difference method in the frequency-space domain is introduced in the migration process, because it can adapt to strong lateral velocity variation and the coefficient is optimized by a hybrid genetic and simulated annealing algorithm. The two measures improve the precision of the approximation dispersion equation. Thus, the imaging effect is improved for areas of high-dip structure and strong lateral velocity variation. The migration imaging of a 2-D SEG/EAGE salt dome model proves that a better imaging effect in these areas is achieved by optimized phase-shift migration operator plus a finite-difference method based on a hybrid genetic and simulated annealing algorithm. The method proposed in this paper is better than conventional methods in imaging of areas of high-dip angle and strong lateral velocity variation. 展开更多
关键词 Migration operator phase-shift plus finite-difference hybrid algorithm genetic andsimulated annealing algorithm optimization coefficient
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HOMOCLINIC SOLUTIONS OF NONLINEAR LAPLACIAN DIFFERENCE EQUATIONS WITHOUT AMBROSETTI-RABINOWITZ CONDITION
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作者 Antonella NASTASI Stepan TERSIAN Calogero VETRO 《Acta Mathematica Scientia》 SCIE CSCD 2021年第3期712-718,共7页
The aim of this paper is to establish the existence of at least two non-zero homoclinic solutions for a nonlinear Laplacian difference equation without using AmbrosettiRabinowitz type-conditions. The main tools are mo... The aim of this paper is to establish the existence of at least two non-zero homoclinic solutions for a nonlinear Laplacian difference equation without using AmbrosettiRabinowitz type-conditions. The main tools are mountain pass theorem and Palais-Smale compactness condition involving suitable functionals. 展开更多
关键词 Difference equations homoclinic solutions non-zero solutions (p q)-Laplacian operator
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Small Sample Estimation in Dynamic Panel Data Models: A Simulation Study 被引量:1
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作者 Lorelied.A. Santos Erniel B. Barrios 《Open Journal of Statistics》 2011年第2期58-73,共16页
We used simulated data to investigate both the small and large sample properties of the within-groups (WG) estimator and the first difference generalized method of moments (FD-GMM) estimator of a dynamic panel data (D... We used simulated data to investigate both the small and large sample properties of the within-groups (WG) estimator and the first difference generalized method of moments (FD-GMM) estimator of a dynamic panel data (DPD) model. The magnitude of WG and FD-GMM estimates are almost the same for square panels. WG estimator performs best for long panels such as those with time dimension as large as 50. The advantage of FD-GMM estimator however, is observed on panels that are long and wide, say with time dimension at least 25 and cross-section dimension size of at least 30. For small-sized panels, the two methods failed since their optimality was established in the context of asymptotic theory. We developed parametric bootstrap versions of WG and FD-GMM estimators. Simulation study indicates the advantages of the bootstrap methods under small sample cases on the assumption that variances of the individual effects and the disturbances are of similar magnitude. The boostrapped WG and FD-GMM estimators are optimal for small samples. 展开更多
关键词 Dynamic panel Data Model Within-Groups ESTIMATOR First-Difference Generalized Method of MOMENTS ESTIMATOR PARAMETRIC BOOTSTRAP
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