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On Representation Theorem of G-Expectations and Paths of G-Brownian Motion

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Acta Mathematicae Applicatae Sinica 2009年第3期25卷 539-546页

作者： ming-shang Hu Shi-ge Peng Institute of Mathematics Shandong University Jinan 250100 China

We give a very simple and elementary proof of the existence of a weakly compact family of probability measures {Pθ ： θ∈θ} representing an important sublinear expectation- G-expectation E[·]. We also give a concrete approximation of a bounded continuous function X（ω） by an increasing sequence of cylinder functions Lip（Ω） in order to prove that Cb（Ω） belongs to the completion of Lip（Ω） under the natural norm E[｜·｜].

关键词： Probability and distribution uncertainty G-normal distribution G-Brownian motion continuous paths

A SEMI-ANALYTICAL SOLUTION FOR CHARACTERISTICS OF A DAMRESERVOIR SYSTEM WITH ABSORPTIVE RESERVOIR BOTTOM

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Journal of Hydrodynamics 2008年第6期20卷 727-734页

作者： LI shang-ming LIANG Hong LI Ai-min School of Civil Engineering and Architecture Nanchang University Nanchang 330031 China

In this study, a semi-analytical formulation based on the Scaled Boundary Finite Element Method （SBFEM） was proposed and used to obtain the solution for the characteristics of a two-dimensional dam-reservoir system with absorptive reservoir bottom in the frequency domain. For simplicity, the dam with arbitrary upstream faces was assumed to be rigid and was subjected to a horizontal ground acceleration, while the reservoir with absorptive bottom was assumed to be semi-infinite. The reservoir was divided into two sub-domains： a near-field sub-domain and a far-field sub-domain. The near-field sub-domain with arbitrary geometry was modelled by the Finite Element Method （FEM）, while the effects of the far-field sub-domain which was assumed to be horizontal were described by a semi-analytical formation. The semi-analytical formulation involved the effect of absorptive reservoir bottom, as well as the radiation damping effect of a semi-infinite reservoir. A FEM/SBFEM coupling formulation was presented to solve dam-reservoir coupled problems. The accuracy and efficiency of the coupling formulation were demonstrated by computing some benchmark examples. Highly accurate results are produced even if the near-field sub-domain is very small.

关键词： dam-reservoir interaction absorptive bottom SBFEM Hydraulic pressure FEM/SBFEM coupling formulation

Development of a 1200 fine group nuclear data library for advanced nuclear systems

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Nuclear Science and Techniques 2017年第5期28卷 48-52页

作者： Jun Zou Lei-ming shang Fang Wang Li-Juan Hao Key Laboratory of Neutronics and Radiation Safety Institute of Nuclear Energy Safety Technology Chinese Academy of Sciences Hefei 230031 China

Accurate and reliable nuclear data libraries are essential for calculation and design of advanced nuclea systems. A 1200 fine group nuclear data library Hybrid Evaluated Nuclear Data Library/Fine Group(HENDL/FG with neutrons of up to 150 Me V has been developed to improve the accuracy of neutronics calculations and anal ysis. Corrections of Doppler, resonance self-shielding, and thermal upscatter effects were done for HENDL/FG Shielding and critical safety benchmarks were performed to test the accuracy and reliability of the library. The dis crepancy between calculated and measured nuclea parameters fell into a reasonable range.

关键词： Advanced nuclear system Fine group nuclear data library Effective multiplication factor

Object-based image analysis of suburban landscapes using Landsat-8 imagery

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International Journal of Digital Earth 2019年第6期12卷 720-736页

作者： ming shang Shixin Wang Yi Zhou Cong Du Wenliang Liu Institute of Remote Sensing and Digital Earth Chinese Academy of SciencesBeijingPeople’s Republic of China University of Chinese Academy of Sciences BeijingPeople’s Republic of China

Many experiments of object-based image analysis have been conducted in remote sensing ***,they commonly used highresolution imagery and rarely focused on suburban *** this research,with the Landsat-8 imagery,classification of a suburban area via the object-based approach is achieved using four classifiers,including decision tree(DT),support vector machine(SVM),random trees(RT),and naive Bayes(NB).We performed feature selection at different sizes of segmentation scale and evaluated the effects of segmentation and tuning parameters within each classifier on classification *** results showed that the influence of shape on overall accuracy was greater than that of compactness,and a relatively low value of shape should be set with increasing scale *** DT,the optimal maximum depth usually varied from 5 to *** SVM,the optimal gamma was less than or equal to 10^(-2),and its optimal C was greater than or equal to 10^(2).For RT,the optimal active variables was less than or equal to 4,and the optimal maximum tree number was greater than or equal to ***,although there was no statistically significant difference between some classification results produced using different classifiers,SVM has a slightly better performance.

关键词： Land cover remote sensing object-based classifier feature selection

Long-Term Effects of Recommendation on the Evolution of Online Systems

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Chinese Physics Letters 2013年第11期30卷 211-214页

作者： ZHAO Dan-Dan ZENG An shang ming-Sheng GAO Jian School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu 610054 Department of Physics University of FribourgChemin du Musée 3CH-1700 FribourgSwitzerland

We employ a bipartite network to describe an online commercial *** of investigating accuracy and diversity in each recommendation,we focus on studying the influence of recommendation on the evolution of the online bipartite *** analysis is based on two benchmark datasets and several well-known recommendation *** structure properties investigated include item degree heterogeneity,clustering coefficient and degree *** work highlights the importance of studying the effects and performance of recommendation in long-term evolution.

关键词： bipartite correlation evolution

Empirical Analysis on the Human Dynamics of a Large-Scale Short Message Communication System

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Chinese Physics Letters 2011年第6期28卷 352-355页

作者： ZHAO Zhi-Dan XIA Hu shang ming-Sheng ZHOU Tao Web Sciences Center School of Computer Science and EngineeringUniversity of Electronic Science and Technology of ChinaChengdu 610054 Department of Modern Physics University of Science and Technology of ChinaHefei 230026

Research on human behavior has attracted increasing attention recently because of its scientific significance and potential *** empirical results have indicated that the timing of many human activities follows non-Poisson *** analyze a real-life huge dataset of short message communication with 6326713 users and 37577781 records during the 2006 Chinese New *** results show that the number of short message sendings,the interevent time between two consecutive short message sendings and the response time all follow heavy-tailed *** further observe a strongly positive correlation between the activity and the power-law exponent of the interevent time *** addition,the short message communication system displays a bursty property yet no memory effects,which is in particular different from some well-studied human-activited systems such as email-sending,library-loaning and file printing.

关键词： email Message printing

Atomistic study on the microscopic mechanism of grain boundary embrittlement induced by small dense helium bubbles in iron

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Nuclear Science and Techniques 2024年第3期35卷 84-95页

作者： Lei Peng Yong-Jie Sun Jing-Yi Shi Yi-Fei Liu shang-ming Chen Liu-Liu Li State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230027China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610213China

The helium bubbles induced by 14 MeV neutron irradiation can cause intergranular fractures in reduced activation ferritic martensitic steel,which is a candidate structural material for fusion *** order to elucidate the susceptibility of different grain boundaries(GBs)to helium-induced embrittlement,the tensile fracture processes of 10 types of GBs with and without helium bubbles in body-centered cubic(bcc)iron at the relevant service temperature of 600 K were investigated via molecular dynamics *** results indicate that in the absence of helium bubbles,the GBs studied here can be classified into two distinct categories:brittle GBs and ductile *** atomic scale analysis shows that the plastic deformation of ductile GB at high temperatures originates from complex plastic deformation mechanisms,including the Bain/Burgers path phase transition and deformation twinning,in which the Bain path phase transition is the most dominant plastic deformation ***,the presence of helium bubbles severely inhibits the plastic deformation channels of the GBs,resulting in a significant decrease in elongation at *** bubble-decorated GBs,the ultimate tensile strength increases with the increase in the misorientation ***,the coherent twin boundary∑3{112}was found to maintain relatively high fracture strength and maximum failure strain under the influence of helium bubbles.

关键词： Helium bubble Grain boundary Embrittlement Reduced activation ferritic martensitic steel Molecular dynamics Bain path

Interactive Image Enhancement by Fuzzy Relaxation

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International Journal of Automation and computing 2007年第3期4卷 229-235页

作者： shang-ming Zhou John Q.Can Li-Da Xu Robert John School of Computing De Montfort UniversityLeicester LE1 9BHUK Department of Computer Science University of EssexColchester CO3 4SQUK Department of Information Technology and Decision Sciences Old Dominion UniversityNorfolk VA23529-0218USA

In this paper, an interactive image enhancement （HE） technique based on fuzzy relaxation is presented, which allows the user to select different intensity levels for enhancement and intermit the enhancement process according to his/her preference in applications. First, based on an analysis of the convergence of a fuzzy relaxation algorithm for image contrast enhancement, an improved version of this algorithm, which is called FuzzIIE Method 1, is suggested by deriving a relationship between the convergence regions and the parameters in the transformations defined in the algorithm. Then a method called FuzzIIE Method 2 is introduced by using a different fuzzy relaxation function, in which there is no need to re-select the parameter values for interactive image enhancement. Experimental results are presented demonstrating the enhancement capabilities of the proposed methods under different conditions.

关键词： Interactive image enhancement fuzzy relaxation fuzzy set crossover point convergence.

Impact of climate factors on runoff in the Kaidu River watershed:path analysis of 50-year data

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Journal of Arid Land 2011年第2期3卷 132-140页

作者： XueMei LI LanHai LI LingPeng GUO FeiYun ZHANG Suwannee ADSAVAKULCHAI ming shang Xinjiang Laboratory of Water Cycle and Utilization in Arid Zone Xinjiang Institute of Ecology and Geography Chinese Acad-emy of Sciences Urumqi 830011 China Graduate University of Chinese Academy of Sciences Beijing 100049 China School of Engineering University of the Thai Chamber of Commerce Bangkok 10400 Thailand

Runoff formation is a complex meteorological-hydrological process impacted by many factors,especially in the inland river *** on the data of daily mean air temperature,precipitation and runoff during the period of 1958-2007 in the Kaidu River watershed,this paper analyzed the changes in air temperature,precipitation and runoff and revealed the direct and indirect impacts of daily air temperature and precipitation on daily runoff by path *** results showed that mean temperature time series of the annual,summer and autumn had a significant fluctuant increase during the last 50 years（P 0.05）.Only winter precipitation increased significantly（P 0.05） with a rate of 1.337 mm/*** annual and winter runoff depthes in the last 50 years significantly increased with the rates of 7.11 mm/10a and 1.85 mm/10a,*** driving function of both daily temperature and precipitation on daily runoff in annual and seasonal levels is significant in the Kaidu River watershed by correlation *** result of path analysis showed that the positive effect of daily air temperature on daily runoff depth is much higher than that of daily precipitation in annual,spring,autumn and winter,however,the trend is opposite in summer.

关键词： climate factors runoff formation inland river Kaidu River watershed path analysis