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Strong Convergence for Weighted Sums of Negatively Associated Arrays

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Chinese Annals of Mathematics,Series B 2010年第2期31卷 273-288页

作者： Hanying LIANG Jingjing ZHANG department of Mathematics Tongji University Shanghai 200092 China.

Let {Xni} be an array of rowwise negatively associated random variables and Tnk=k∑i=1 i^a Xni for a ≥ -1, Snk =∑｜i｜≤k Ф（i/nη）1/nη Xni for η∈（0,1],where Ф is some function. The author studies necessary and sufficient conditions of ∞∑n=1 AnP（max 1≤k≤n｜Tnk｜〉εBn）〈∞ and ∞∑n=1 CnP（max 0≤k≤mn｜Snk｜〉εDn）〈∞ for all ε 〉 0, where An, Bn, Cn and Dn are some positive constants, mn ∈ N with mn /nη →∞. The results of Lanzinger and Stadtmfiller in 2003.are extended from the i.i.d, case to the case of the negatively associated, not necessarily identically distributed random variables. Also, the result of Pruss in 2003.on independent variables reduces to a special case of the present paper; furthermore, the necessity part of his result is complemented.

关键词： Tail probability Negatively associated random variable Weighted sum

HARMONIC FUNCTIONS ON PRODUCT OF CERTAIN KAHLER MANIFOLDS WITH A POLE

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Chinese Annals of Mathematics,Series B 2001年第3期22卷 381-384页

作者： YANG YIHU department of Mathematics, tongji university, shanghai 200092, China ICTP, P. O. Box 586, Trieste 3.100, Italy. department of Mathematics Tongji University Shanghai 200092 China ICTP P. O. Box 586 Trieste 34100 Italy

It is proved that there is no nonconstant harmonic function of finite energy on product of certain Kahlerian manifolds with a pole.

关键词： Harmonic functions Kahlerian manifolds with a pole Pluriharmonicity

Some variational principles in electroelastic media under finite deformation

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Science China(Physics,Mechanics & Astronomy) 2008年第9期51卷 1390-1402页

作者： KUANG ZhenBang department of engineering Mechanics,shanghai Jiaotong {3.,shanghai 200240,China department of engineering Mechanics Shanghai Jiaotong University Shanghai 200240 China

It is proposed that the universal thermodynamic energy variational principle is in-cluded in the first law of thermodynamics. Some variational principles in the elec-troelastic media under finite deformation are derived from this universal thermo-dynamic variational principle. It is suggested that in the general electroelastic analysis the environment should be considered together with the discussed elec-troelastic medium. For the variational principle of nonlinear electroelastic media the variation of the electric potential is coupled with the virtual displacement,and the variation of the initial volume should be considered. The Maxwell stress in the initial configuration is naturally derived from this variational principle and it is unique in the second order precision.

关键词： first law of thermodynamics variational principle the electroelastic media the governing equation

Admissibilities of linear estimator in a class of linear models with a multivariate t error variable

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Science China Mathematics 2010年第8期53卷 2011-2019页

作者： YANG GuoQing 1 & WU QiGuang 2 1 department of Mathematics,tongji university,shanghai 200092,China 2 Institute of Systems Science,Academy of Mathematics and Systems Science,Chinese Academy of Sciences,Beijing 100190,China 1. department of Mathematics Tongji University Shanghai 200092 China2. Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China

This paper discusses admissibilities of estimators in a class of linear models,which include the following common models:the univariate and multivariate linear models,the growth curve model,the extended growth curve model,the seemingly unrelated regression equations,the variance components model,and so *** is proved that admissible estimators of functions of the regression coefficient β in the class of linear models with multivariate t error terms,called as Model II,are also ones in the case that error terms have multivariate normal distribution under a strictly convex loss function or a matrix loss *** is also proved under Model II that the usual estimators of β are admissible for p 2 with a quadratic loss function,and are admissible for any p with a matrix loss function,where p is the dimension of β.

关键词： multivariate t distribution convex loss quadratic loss matrix loss admissible estimator

TYPICAL DAMAGES OF TUNNEL ENTRANCE IN WORKING AND CASE STUDIES

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TYPICAL DAMAGES OF TUNNEL ENTRANCE IN WORKING AND CASE STUDI...

A Study on 3.D Nonlinear Rheological Behavior of Soft Rocks——Applications in Environmental and Safety Problems due to Underground Mining Construction

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作者： XIA Caichu~(1 2) ZHAO Xu~(1 2) (1 geotechnical Key Laboratory of tongji university tongji university {3. China 2 department of geotechnical engineering tongji university {3. China)

＜正＞Tunnel entrance consists of slopes,lining around tunnel portal and tunnel portal. Different kinds of deficiencies can happen on entrance of a *** main mechanism and reasons causing deficiencies are:bias pressure,creeping,slope sliding,bearing capacity deficiency, rockfall,earthquake and *** to the rules summarized form literatures and practices, damages of two working tunnels were *** is of significance to other practice.

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A Study on 3-D Nonlinear Rheological Behavior of Soft Rocks...

Smoothness for the collision local times of bifractional Brownian motions

作者： Sun Jun (department of geotechnical engineering,{3.,shanghai 200092,China)

1 Environmental and safety problems in mining engineering Around the stopping area in mine construction,the initial ground stress equilibrium state of rock mass is definitely disturbed,often appearing excessive displacement in rocks surrounding the coal tunnel(roadway) which may result in environmental damage,including ground surface movement with extending large area,rock strata deformation and non-contin- uous failures such as rock split and roof collapse,etc.,even endangering the safety of road- way *** weak and soft rock mines,such situation sometimes turns out to be even more *** sort of so-called"mining subsidence"problems are very common and vex- atious phenomena in China and other countries alike.

关键词： soft rock nonlinear rheological behavior constitutive model finite element method mining construction environmental & safety problem

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Science China Mathematics 2011年第9期54卷 1859-1873页

作者： SHEN GuangJun 1,2,& YAN LiTan 3.1 department of Mathematics,East China university of Science and Technology,shanghai 20023.,China 2 department of Mathematics,Anhui Normal university,Wuhu 241000,China 3.department of Mathematics,Donghua university,shanghai 201620,China 1. department of Mathematics East China University of Science and Technology Shanghai 200237 China2. Department of Mathematics Anhui Normal University Wuhu 241000 China3. Department of Mathematics Donghua University Shanghai 201620 China

Let B^Hi,Ki ={ Bt^Hi,Ki, t ≥ 0}, i= 1, 2 be two independent bifractional Brownian motions with respective indices Hi ∈ （0, 1） and K∈ E （0, 1]. One of the main motivations of this paper is to investigate f0^Tδ（Bs^H1 ,K1 - the smoothness of the collision local time, introduced by Jiang and Wang in 2009, IT = f0^T δ（Bs^H1,K1）ds, T 〉 0, where 6 denotes the Dirac delta function. By an elementary method, we show that iT is smooth in the sense of the Meyer-Watanabe if and only if min{H-1K1, H2K2} 〈-1/3.

关键词： bifractional Brownian motion collision local time intersection local time chaos expansion

Computational model for perception of objects and motions

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Science China(Life Sciences) 2008年第6期51卷 526-536页

作者： YANG WenLu1,2, ZHANG LiQing1 & MA LiBo1 1 department of Computer Science and engineering, shanghai Jiao Tong {3., shanghai 200240, China 2 department of Electronic engineering, shanghai Maritime {3., shanghai 20013., China 1. department of Computer Science and engineering Shanghai Jiao Tong University Shanghai 200240 China 2. department of Electronic engineering Shanghai Maritime University Shanghai 200135 China

Perception of objects and motions in the visual scene is one of the basic problems in the visual system. There exist 'What' and 'Where' pathways in the superior visual cortex, starting from the simple cells in the primary visual cortex. The former is able to perceive objects such as forms, color, and texture, and the latter perceives 'where', for example, velocity and direction of spatial movement of objects. This paper explores brain-like computational architectures of visual information processing. We propose a visual perceptual model and computational mechanism for training the perceptual model. The compu- tational model is a three-layer network. The first layer is the input layer which is used to receive the stimuli from natural environments. The second layer is designed for representing the internal neural information. The connections between the first layer and the second layer, called the receptive fields of neurons, are self-adaptively learned based on principle of sparse neural representation. To this end, we introduce Kullback-Leibler divergence as the measure of independence between neural responses and derive the learning algorithm based on minimizing the cost function. The proposed algorithm is applied to train the basis functions, namely receptive fields, which are localized, oriented, and bandpassed. The resultant receptive fields of neurons in the second layer have the characteristics resembling that of simple cells in the primary visual cortex. Based on these basis functions, we further construct the third layer for perception of what and where in the superior visual cortex. The proposed model is able to perceive objects and their motions with a high accuracy and strong robustness against additive noise. Computer simulation results in the final section show the feasibility of the proposed perceptual model and high efficiency of the learning algorithm.

关键词： visual perception visual cortex computational model receptive fields simple cells complex cells

Multiresolution Terrian Model in GIS

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测绘学报 2002年第Z1期31卷 92-98页

作者： ZHANG Jin 1,TONG Xiao hua 2 (1. department of Surveying and Mapping, Taiyuan university of Technology, Taiyuan 03.024,China 2. department of Surveying and Geo informatics, {3., shanghai 200092,China) department of Surveying and Mapping Taiyuan University of Technology Taiyuan 030024 department of Surveying and Geo-informatics Tongji University 上海 200092

DEM, which becomes a major component of geographic information processing in earth and engineering sciences, has been studied in the GIS literature for a long time. We use DEM to represent the terrain in GIS. The more data are available, the better representations of a terrain can be built. But not all tasks in the framework of a given application necessarily require the same accuracy, and even a single task may need different levels of accuracy in different areas of the domain. Multiresolution models, such as LOD, offer the possibility of representing and analyzing a terrain at a range of different levels of detail. In this paper, some key issues in multiresolution DEM model are studied. Three main models are focused on Hierarchical TIN(HTIN), multiresolution terrain model based Delaunay and Hierarchical Dynamic Simplification. The advantages and disadvantages of these methods are analyzed. The technology of tile to tile edge match is studied to maintain the consistency between adjacent edges and tile edges in HTIN model. And the Hypergraph based Objected oriented Model(HOOM) is presented to divide and code spatial area and describe the terrain feature in adding and deleting points based on Delaunay rule retriangulating. The conclusions have been drawn in the end.

关键词： DEM multiresolution LOD GIS