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REGULARITY OF POISSON EQUATION IN SOME LOGARITHMIC SPACE
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作者 Jia Huilian Li Dongsheng Wang Lihe 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2007年第1期29-36,共8页
In this note, the regularity of Poisson equation -△u = f with f lying in logarithmic function space L^P(LogL)^a(Ω)(1 〈 p 〈 ∞, a ∈ R) is studied. The result of the note generalizes the W^2,p estimate of Poi... In this note, the regularity of Poisson equation -△u = f with f lying in logarithmic function space L^P(LogL)^a(Ω)(1 〈 p 〈 ∞, a ∈ R) is studied. The result of the note generalizes the W^2,p estimate of Poisson equation in L^P(Ω). 展开更多
关键词 maximal function logarithmic function space distribution function.
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A New Function for Modelling Diameter Frequency Distribution in the Tropical Rain Forest of Xishuangbanna,Southwest of China 被引量:6
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作者 LuYuanchang LeiXiangdong JiangLei 《Forestry Studies in China》 CAS 2003年第2期1-6,共6页
Permanent plots in the montane tropical rain forests in Xishuangbanna, southwest China, were established, and different empirical models, based on observation data of these plots in 1992, were built to model diameter ... Permanent plots in the montane tropical rain forests in Xishuangbanna, southwest China, were established, and different empirical models, based on observation data of these plots in 1992, were built to model diameter frequency distributions. The focus of this study is on predicting accuracy of stem number in the larger diameter classes, which is much more important than that of the smaller trees, from the view of forest management, and must be adequately considered in the modelling and estimate. There exist 3 traditional ways of modelling the diameter frequency distribution: the negative exponential function model, limiting line function model, and Weibull distribution model. In this study, a new model, named as the logarithmic J-shape function, together with the others, was experimented and was found as a more suitable model for modelling works in the tropical forests. 展开更多
关键词 tropical forests diameter distribution modelling logarithmic J-shape function
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A LAW OF THE ITERATED LOGARITHM FOR NEAREST NEIGHBOR ESTIMATION OF MULTIVARIATE DENSITY FUNCTION
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作者 洪圣岩 陈规景 +1 位作者 孔繁超 高集体 《Acta Mathematica Scientia》 SCIE CSCD 1992年第4期472-478,共7页
Let X be a d-dimensional random vector with unknown density function f(z) = f (z1, ..., z(d)), and let f(n) be teh nearest neighbor estimator of f proposed by Loftsgaarden and Quesenberry (1965). In this paper, we est... Let X be a d-dimensional random vector with unknown density function f(z) = f (z1, ..., z(d)), and let f(n) be teh nearest neighbor estimator of f proposed by Loftsgaarden and Quesenberry (1965). In this paper, we established the law of the iterated logarithm of f(n) for general case of d greater-than-or-equal-to 1, which gives the exact pointwise strong convergence rate of f(n). 展开更多
关键词 A LAW OF THE ITERATED LOGARITHM FOR NEAREST NEIGHBOR ESTIMATION OF MULTIVARIATE DENSITY function exp
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Beach Profiles Characteristics Along Giao Thuy and Hai Hau Coasts,Vietnam:A Field Study 被引量:2
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作者 NGUYEN Viet Thanh 郑金海 张弛 《China Ocean Engineering》 SCIE EI 2012年第4期699-712,共14页
Giao Thuy and Hai Hau coasts are located in Nam Dinh province, Vietnam, with a total coastline of 54.42 km in length. The sea-dike system has been seriously damaged and there have been many dike breaches which caused ... Giao Thuy and Hai Hau coasts are located in Nam Dinh province, Vietnam, with a total coastline of 54.42 km in length. The sea-dike system has been seriously damaged and there have been many dike breaches which caused floods and losses. This situation is considered of a general representative for coastal area in the northern part of Vietnam. A variety of studies have shown that the gradient in the longshore sediment transport rate and the offshore fine sediment lost are the main mechanisms causing the beach erosion. This study presents a field investigation of the beach profiles at Giao Thuy and Hai Hau beaches. Three types of empirical functions for the equilibrium beach profile are applied and compared with the observations. Results show that all observed beach profiles can be described by a single function. However, one specific equilibrium profile equation is not sufficient to assess all beach profiles. In Section 1 of Giao Thuy and Section 3 of Hai Thinh beaches, beach profiles are consistent with the logarithmic function, while the exponential function fits well in Section 2. This difference is explained with respect to coastal morphology, sediment characteristics and hydrodynamic conditions which vary in site. An analysis of the validity of the beach profile functions is recommended for the numerical modeling and engineering designs in this area. 展开更多
关键词 beach profile field study power function exponential function logarithmic function
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Two-Stage Resource Allocation Scheme for Three-Tier Ultra-Dense Network 被引量:5
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作者 Junwei Huang Pengguang Zhou +2 位作者 Kai Luo Zhiming Yang Gongcheng He 《China Communications》 SCIE CSCD 2017年第10期118-129,共12页
In 5 G Ultra-dense Network(UDN), resource allocation is an efficient method to manage inter-small-cell interference. In this paper, a two-stage resource allocation scheme is proposed to supervise interference and reso... In 5 G Ultra-dense Network(UDN), resource allocation is an efficient method to manage inter-small-cell interference. In this paper, a two-stage resource allocation scheme is proposed to supervise interference and resource allocation while establishing a realistic scenario of three-tier heterogeneous network architecture. The scheme consists of two stages: in stage I, a two-level sub-channel allocation algorithm and a power control method based on the logarithmic function are applied to allocate resource for Macrocell and Picocells, guaranteeing the minimum system capacity by considering the power limitation and interference coordination; in stage II, an interference management approach based on K-means clustering is introduced to divide Femtocells into different clusters. Then, a prior sub-channel allocation algorithm is employed for Femtocells in diverse clusters to mitigate the interference and promote system performance. Simulation results show that the proposed scheme contributes to the enhancement of system throughput and spectrum efficiency while ensuring the system energy efficiency. 展开更多
关键词 ultra-dense network resource allocation logarithmic function K-means
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Estimation of postseismic deformation parameters from continuous GPS data in northern Sumatra after the 2004 Sumatra-Andaman earthquake
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作者 Bimar Anugrah Irwan Meilano +1 位作者 Endra Gunawan Joni Efendi 《Earthquake Science》 CSCD 2015年第5期347-352,共6页
Continuous global positioning system (GPS) in northern Sumatra detected signal of the ongoing physical process of postseismic deformation after the M9.2 2004 Sumatra-Andaman earthquake. We analyze the character- ist... Continuous global positioning system (GPS) in northern Sumatra detected signal of the ongoing physical process of postseismic deformation after the M9.2 2004 Sumatra-Andaman earthquake. We analyze the character- istics of postseismic deformation of the 2004 earthquake based on GPS networks operated by BIG, and the others named AGNeSS, and SuGAr networks located in northern Sumatra. We use a simple analytical logarithmic and exponential function to evaluate the postseismic deforma- tion parameters of the 2004 earthquake. We find that GPS data in northern Sumatra during time periods of 2005-2012 are fit better using the logarithmic function with dog of 104.2 ± 0.1 than using the exponential function. Our result clearly indicates that other physical mechanisms of post- seismic deformation should be taken into account rather than a single physical mechanism of afterslip only. 展开更多
关键词 The 2004 Sumatra-Andaman earthquakeContinuous GPS data logarithmic and exponential functions
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Application of Physics Phenomenon Model Towards Economic Symptoms in Indonesia (Spring Oscillation Model and Rupiah Rate Exchange)
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作者 Kunlestiowati H. Nani Yuningsih Sardjito 《Economics World》 2018年第2期133-141,共9页
A physical phenomenon can be duplicated similarly to different phenomenon. Based on these facts, the application of physics phenomenon model towards the economic cases that occurred in Indonesia will be discussed. Phy... A physical phenomenon can be duplicated similarly to different phenomenon. Based on these facts, the application of physics phenomenon model towards the economic cases that occurred in Indonesia will be discussed. Physical phenomenon to be discussed is the loaded oscillation spring, while the economic case is the dynamics of the Rupiah against foreign currencies, namely U.S. Dollars. Symptoms of the analyzed oscillations involve vibration load on the spring, with the mass load changes against time; for free oscillation, damped oscillation, forced oscillation, as well as forced damped oscillation. Oscillation is modeled into a non homogenous second order differential equation, which results in a solution of the deviation function of time in the form of logarithmic harmonic function. Obtained solutions of physical phenomenon model are matched with the dynamics of the exchange rate data for both steady state, as well as to the condition shortly after the surge (crash). Models are quite satisfactory, especially when being associated with the occurrence of momentary interruption followed by a relaxation mechanism, both for amplitude and period. 展开更多
关键词 spring oscillations mass change exchange rate logarithmic harmonic function
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An improve d smoothe d particle hydrodynamics approach using new inverse kernel function
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作者 J.R.Rajapriyadharshini 《Journal of Ocean Engineering and Science》 SCIE 2022年第4期327-336,共10页
The main limitation of Smoothed Particle Hydrodynamics(SPH)method that resists the method’s poten-tial is its lack of providing stability and accuracy to the numerical technique.We improve the accuracy of the standar... The main limitation of Smoothed Particle Hydrodynamics(SPH)method that resists the method’s poten-tial is its lack of providing stability and accuracy to the numerical technique.We improve the accuracy of the standard SPH technique,by formulating a new inverse logarithmic kernel function.This new kernel function is derived based on the underlying properties of kernel functions.The approximation technique used here is based on the Moving Least Squares based technique.The adequacy of the proposed ker-nel function is tested by simulation of 2D shock wave propagation and 3D dam-break free surface flow against a cuboidal obstacle.The method was validated against experimental data by Kleefsman et al.,[1].The numerical results reveal that our new SPH approach using inverse logarithmic kernel function outper-forms existing ones in particle restoration,zero error,better accuracy and enhanced efficiency in kernel approximation.This new kernel function showed some improvement over existing kernels by showing very less error approximation value of 0.035h 2.The results showed some improvements over standard technique by being capable of handling problems with large deformations accurately and precisely. 展开更多
关键词 Inverse logarithmic function Moving least squares approximation Shock wave propagation 3D dam-break flow Zero error
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Complete monotonicity of a function involving the divided diference of digamma functions
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作者 QI Feng LUO QiuMing GUO BaiNi 《Science China Mathematics》 SCIE 2013年第11期2315-2325,共11页
In the paper, necessary and sufficient conditions are provided for a function involving the divided difference of two psi functions to be completely monotonic. Consequently, a class of inequalities for sums are presen... In the paper, necessary and sufficient conditions are provided for a function involving the divided difference of two psi functions to be completely monotonic. Consequently, a class of inequalities for sums are presented, the logarithmically complete monotonicity of a function involving the ratio of two gamma functions are derived, and two double inequalities for bounding the ratio of two gamma functions are discovered. 展开更多
关键词 necessary and sufficient condition completely monotonic function logarithmically completelymonotonic function divided difference psi function inequality for sums bound for the ratio of two gammafunctions
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A Functional LIL for Integrated α Stable Process
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作者 Rong Mao ZHANG Zheng Yan LIN 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2010年第2期393-404,共12页
Let {X(t),t ∈ R+} be an integrated α stable process. In this paper, a functional law of the iterated logarithm (LIL) is derived via estimating the small ball probability of X. As a corollary,, the classical C... Let {X(t),t ∈ R+} be an integrated α stable process. In this paper, a functional law of the iterated logarithm (LIL) is derived via estimating the small ball probability of X. As a corollary,, the classical Chung LIL of X is obtained. Furthermore, some results about the weighted occupation measure of X(t) are established. 展开更多
关键词 integrated α stable process functional law of the integrated logarithm small ball probability weighted occupation measure
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Chung’s functional law of the iterated logarithm for the Brownian sheet
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作者 Yonghong LIU Ting ZHANG Yiheng TANG 《Frontiers of Mathematics in China》 SCIE CSCD 2022年第6期1015-1024,共10页
In this paper,we investigate functional limit problem for path of a Brownian sheet,Chung’s functional law of the iterated logarithm for a Brownian sheet is obtained.The main tool in the proof is large deviation and s... In this paper,we investigate functional limit problem for path of a Brownian sheet,Chung’s functional law of the iterated logarithm for a Brownian sheet is obtained.The main tool in the proof is large deviation and small deviation for a Brownian sheet. 展开更多
关键词 Brownian sheet Chung’s functional law of the iterated logarithm
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A Functional LIL for m-Fold Integrated Brownian Motion
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作者 Rongmao ZHANG Zhengyan LIN 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2006年第4期459-472,共14页
Let {Xm(t), t∈R+} be an m-Fold integrated Brownian motion. In this paper, with the help of small ball probability estimate, a functional law of the iterated logarithm (LIL) for Xm(t) is established. This exten... Let {Xm(t), t∈R+} be an m-Fold integrated Brownian motion. In this paper, with the help of small ball probability estimate, a functional law of the iterated logarithm (LIL) for Xm(t) is established. This extends the classic Chung type liminf result for this process. Furthermore, a result about the weighted occupation measure for Xm(t) is also obtained. 展开更多
关键词 m-Fold integrated Brownian motion functional law of the integrated logarithm Small ball probability Weighted occupation measure
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FUNCTIONAL LAW OF ITERATED LOGARITHM FOR ADDITIVE FUNCTIONALS OF REVERSIBLE MARKOV PROCESSES
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作者 吴黎明 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2000年第2期149-161,共13页
Using the forward-backward martingale decomposition and the martingale limit theorems, we establish the functional law of iterated logarithm for an additive functional (At) of a reversible Markov process, under the mi... Using the forward-backward martingale decomposition and the martingale limit theorems, we establish the functional law of iterated logarithm for an additive functional (At) of a reversible Markov process, under the minimal condition that σ~2(A)= tim BA_t~2/t exists in R. We extend also t →∞ the previous remarkable functional central limit theorem of Kipnis and Varadhan. 展开更多
关键词 functional law of iterated logarithm forward-backword martingale decomposition reversible markov processes
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The Further Development and Application of Grey Forecasting Model
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作者 LIN Chun-yanDepartment of Mathematics, Dalian University of Technology, Dalian 116024, China 《Systems Science and Systems Engineering》 CSCD 2002年第3期302-305,共4页
In this paper, the method which forecasts original sequences {x (0)(k)} with logarithmic function or with power function has been complemented, and the method which handles original sequences by logarithmic function-... In this paper, the method which forecasts original sequences {x (0)(k)} with logarithmic function or with power function has been complemented, and the method which handles original sequences by logarithmic function-power function transformation or by power function-logarithmic function transformation has been presented, then smooth degree and precision of forecasting of discrete data have been improved. 展开更多
关键词 grey forecasting power function transformation logarithmic function-power function transformation power function-logarithmic function transformation
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A CORPUS-BASED STUDY ON VOCABULARY GROWTH MODEL FOR ENGLISH OF SCIENCE AND TECHNOLOGY
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作者 李晶洁 《Chinese Journal of Applied Linguistics》 2008年第2期93-106,129,共15页
本文采用语料库证据支持的方法,重点考察了科技英语的篇际词汇增长模型。研究表明,现有的数学模型(Brunet模型,Guiraud模型,Tuldava模型及Herdan模型)不能精确地描述科技英语词汇增长曲线。通过对幂函数和对数函数的比较分析,本文构建... 本文采用语料库证据支持的方法,重点考察了科技英语的篇际词汇增长模型。研究表明,现有的数学模型(Brunet模型,Guiraud模型,Tuldava模型及Herdan模型)不能精确地描述科技英语词汇增长曲线。通过对幂函数和对数函数的比较分析,本文构建了新的词汇增长模型,并应用此模型推导出科技英语的理论词汇增长曲线及其95%双向置信区间。本研究对EFL教学有显著意义。新的词汇增长模型可用于推断任意给定语篇的词汇量以及生成任意词汇量需要的语篇数。 展开更多
关键词 vocabulary growth growth model logarithmic function power law
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Hyperspectral image unmixing algorithm based on endmember-constrained nonnegative matrix factorization 被引量:1
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作者 Yan ZHAO Zhen ZHOU +2 位作者 Donghui WANG Yicheng HUANG Minghua YU 《Frontiers of Optoelectronics》 EI CSCD 2016年第4期627-632,共6页
The objective function of classical nonnegative matrix factorization (NMF) is non-convexity, which affects the obtaining of optimal solutions. In this paper, we proposed a NMF algorithm, and this algorithm was based... The objective function of classical nonnegative matrix factorization (NMF) is non-convexity, which affects the obtaining of optimal solutions. In this paper, we proposed a NMF algorithm, and this algorithm was based on the constraint of endmember spectral correlation minimization and endmember spectral difference max- imization. The size of endrnember spectral overall- correlation was measured by the correlation function, and correlation function was defined as the sum of the absolute values of every two correlation coefficient between the spectra. In the difference constraint of the endmember spectra, the mutation of matrix trace was slowed down by introducing the natural logarithm function. Combining the image decomposition error with the influences of end- member spectra, in the objective function the projection gradient was used to achieve NMF. The effectiveness of algorithm was verified by the simulated hyperspeetral images and real hyperspectral images. 展开更多
关键词 hyperspeclral image UNMIXING nonnegativematrix factorization (NMF) correlation logarithm function
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How big are the Csorgo-Revesz increments of two-parameter Wiener processes?
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作者 WANG WenshengDepartment of Mathematics, Hangzhou Teacher’s College, Hangzhou 310012, China Institute of Applied Mathematics, Chinese Academy of Sciences, Beijing 100080, China 《Science China Mathematics》 SCIE 2004年第6期894-907,共14页
In this paper, we prove a theorem on the set of limit points of the increments of a two-parameter Wiener process via establishing a large deviation principle on the increments of the two-parameter Wiener process.
关键词 two-parameter Wiener process INCREMENT functional law of the iterated logarithm large deviation.
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On Global and Local Properties of the Trajectories of Gaussian Random Fields——A Look Through the Set of Limit Points
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作者 Wen Sheng WANG Zhong Gen SU Yi Min XIAO 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2020年第2期137-152,共16页
This paper studies the global and local properties of the trajectories of Gaussian random fields with stationary increments and proves sufficient conditions for Strassen's functional laws of the iterated logarithm... This paper studies the global and local properties of the trajectories of Gaussian random fields with stationary increments and proves sufficient conditions for Strassen's functional laws of the iterated logarithm at zero and infinity respectively.The sets of limit points of those Gaussian random fields are obtained.The main results are applied to fractional Riesz-Bessel processes and the sets of limit points of this field are obtained. 展开更多
关键词 Fractional Riesz-Bessel processes functional law of the iterated logarithm Gaussian random fields large deviation principle
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