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Simplified Calculation Methods for All-Vertical-Piled Wharf in Offshore Deep Water

China Ocean Engineering 2017年第2期31卷 182-191页

作者： WANG yuan-zhan HE Lin-lin State Key Laboratory for Simulation & Safety of Hydraulic Engineering Tianjin Key Laboratory of Harbor & Ocean EngineeringTianjin University College of River and Ocean Engineering Key Laboratory of Regulation Technology for Inland Waterway in Transportation IndustryKey Laboratory of Hydraulic and Waterway Engineering of Ministry of EducationChongqing Jiaotong University

All-vertical-piled wharf is a kind of high-piled wharf, but it is extremely different from the traditional ones in some aspects, such as the structural property, bearing characteristics, failure mechanism, and static or dynamic calculation methods. In this paper, the finite element method （FEM） and theoretical analysis method are combined to analyze the structural property, bearing behavior and failure mode of the all-vertical-piled wharf in offshore deep water, and to establish simplified calculation methods determining the horizontal static ultimate bearing capacity and the dynamic response for the all-vertical-piled wharf. Firstly, the bearing capability and failure mechanism for all-vertical-piled wharf are studied by use of FEM, and the failure criterion is put forward for all-vertical-piled wharf based on the ＇plastic hinge＇. According to the failure criterion and P-Y curve method, the simplified calculation method of the horizontal static ultimate bearing capacity for all-vertical-piled wharf is proposed, and it is verified that the simplified method is reasonable by comparison with the FEM. Secondly, the displacement dynamic magnification factor for the all-vertical-piled wharf under wave cyclic loads and ship impact loads is calculated by the FEM and the theory formula based on the single degree of freedom （SDOF） system. The results obtained by the two methods are in good agreement with each other, and the simplified calculation method of the displacement dynamic magnification factor for all-vertical-piled wharf under dynamic loads is proposed. Then the simplified calculation method determining the dynamic response for the all-vertical-piled wharf is proposed in combination with P-Y curve method. That is, the dynamic response of the structure can be obtained through the static calculation results of P-Y curve method multiplied by the displacement dynamic magnification factor. The feasibility of the simplified dynamic response method is verified by compariso

关键词： all-vertical-piled wharf failure criterion plastic hinge dynamic amplification coefficient simplified calculation methods

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Bayesian edge detector for SAR imagery using discontinuity-adaptive Markov random feld modeling

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Chinese Journal of Aeronautics 2013年第6期26卷 1534-1543页

作者： yuan zhan He You Cai Fuqing Research Institute of Information Fusion Technology Naval Aeronautical and Astronautical University

Synthetic aperture radar（SAR）image is severely affected by multiplicative speckle noise,which greatly complicates the edge *** this paper,by incorporating the discontinuityadaptive Markov random feld（DAMRF）and maximum a posteriori（MAP）estimation criterion into edge detection,a Bayesian edge detector for SAR imagery is accordingly *** the proposed detector,the DAMRF is used as the a priori distribution of the local mean reflectivity,and a maximum a posteriori estimation of it is thus obtained by maximizing the posteriori energy using gradient-descent *** normalized ratios constructed in different directions are computed,based on which two edge strength maps（ESMs）are *** fnal edge detection result is achieved by fusing the results of two thresholded *** experimental results with synthetic and real SAR images show that the proposed detector could effciently detect edges in SAR images,and achieve better performance than two popular detectors in terms of Pratt＇s fgure of merit and visual evaluation in most cases.

关键词： Discontinuity-adaptive Markov random feld(DAMRF) Edge detection Local mean reflectivity Maximum a posteriori(MAP) estimation Synthetic aperture radar(SAR

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Quantum Effect in the Mesoscopic RLC Circuits with a Source

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Communications in Theoretical Physics 2005年第6X期44卷 1091-1094页

作者： LIU Jian-Xin YAN zhan-yuan Department of Electrical Engineering North China Electric Power University Baoding 071003 China Department of Applied Physics North China Electric Power University Baoding 071003 China

The research work on the quantum effects in mesoscopic circuits has undergone a rapid development recently, however the whole quantum theory of the mesoscopic circuits should consider the discreteness of the electric charge. In this paper, based on the fundamental fact that the electric charge takes discrete values, the finite-difference Schrodinger equation of the mesoscopic RLC circuit with a source is achieved. With a unitary transformation, the Schrodinger equation becomes the standard Mathieu equation, then the energy spectrum and the wave functions of the system are obtained. Using the WKBJ method, the average of durrents and square of the current are calculated. The results show the existence of the current fluctuation, which causes noise in the circuits. This paper is an application of the whole quantum mesoscopic circuits theory to the fundamental circuits, and the results will shed light on the design of the miniation circuits, especially on the purpose of reducing quantum noise coherent controlling of the mesoscopic quantum states.

关键词： mesoscopic circuit Muthieu equation quantum effect

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Diffractive Scattering Factorization from J/ψ and γ Associated Production in HERA ep Collisions

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Communications in Theoretical Physics 2002年第11期37卷 583-586页

作者： YAN zhan-yuan DUAN Chun-Gui Department of Physics North China Electric Power University Baoding 071003 China Department of Physics Hebei Teachers'' University Shijiazhuang 050016 China CCAST (World Laboratory) P.O. Box 8730 Beijing 100080 China

Using three sets of Pomeron structure functions, the cross sections of J/ψ and γ associated productionvia resolved photon and proton diffractive scatting in ep collision are investigated. It is found that the cross sectionscalculated with various gluon distribution functions of Pomeron are different. The discrepancy is about 1.8 times fordifferential cross sections and 1.7 times for total cross sections. The experimental studies of the process could give valuableinsight in the diffractive production mechanism and test the color-octet mechanism for heavy quarkonium production ina new environment.

关键词：高能物理强子-强子碰撞 J/ψ介子

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Fast Algorithm for Maneuvering Target Detection in SAR Imagery Based on Gridding and Fusion of Texture Features

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Geo-Spatial Information Science 2011年第3期14卷 169-176页

作者： yuan zhan HE You CAI Fuqing Research Institute of Information Fusion Technology Naval Aeronautical and Astronautical University 128 Erma Road Yantai264001 China

Designing detection algorithms with high efficiency for Synthetic Aperture Radar(SAR) imagery is essential for the operator SAR Automatic Target Recognition(ATR) *** work abandons the detection strategy of visiting every pixel in SAR imagery as done in many traditional detection algorithms,and introduces the gridding and fusion idea of different texture fea-tures to realize fast target *** first grids the original SAR imagery,yielding a set of grids to be classified into clutter grids and target grids,and then calculates the texture features in each *** fusing the calculation results,the target grids containing potential maneuvering targets are *** dual threshold segmentation technique is imposed on target grids to obtain the regions of *** fused texture features,including local statistics features and Gray-Level Co-occurrence Matrix(GLCM),are *** efficiency and superiority of our proposed algorithm were tested and verified by comparing with existing fast de-tection algorithms using real SAR *** results obtained from the experiments indicate the promising practical application val-ue of our study.

关键词： synthetic aperture radar imagery target detection texture feature gridding gray-level co-occurrence matrix fusion

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Responses of plant diversity and species composition to the cessation of fertilization in a sandy grassland

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Journal of Forestry Research 2014年第2期25卷 337-342页

作者： Sheng-nan Shi zhan-yuan Yu Qiong Zhao State Key Laboratory of Forest and Soil Ecology Institute of Applied Ecology Chinese Academy of Sciences University of Chinese Academy of Sciences Daqinggou Ecological Station Institute of Applied EcologyChinese Academy of Sciences

Nitrogen was the main limiting nutrient of net primary production in the southeastern Keerqin Sandy Lands, Northeast China. Species richness declined and biomass increased after five consecutive years of nitrogen fertilization of these sandy grasslands （2004-2008）. After fertilization had been stopped for three years （2009-2011）, we surveyed vegetation on previously fertilized plots to quantify changes in commu- nity composition. Respect species richness showed an increasing trend over time since the cessation of fertilization. Respect vegetation height and coverage showed decreasing trends over time since the cessation of fertilization. Species composition changed after fertilization ceased, the dominant species shifting from Cannabis sativa, Phragmites communis and Chenopodium acuminaturn in 2008 to Cannabis sativa, Phragmites communis and Artemisia scoparia in 2011. Dominance of dominant species declined from 66.2% in 2008 to 57.5% in 2011. The importance value of annual plants in the earlier nitrogen addition plots was higher than in control plots, but the differences were not significant in 2011. The importance value of perennial plants differed significantly between treatments from 2009 to 2011. The reversion rate not only differed be- tween community characteristics, but also between functional groups in the same community characteristic. Although the residual effect of nitrogen addition on vegetation was still observed three years after fertilization ceased, the vegetation showed signs of recovery.

关键词： nitrogen fertilization recovery Keerqin Sandy Lands vegetation

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Quantum Effects of Mesoscopic Inductance and Capacity Coupling Circuits

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Communications in Theoretical Physics 2006年第6期45卷 1126-1130页

作者： LIU Jian-Xin AN zhan-yuan SONG Yong-Hua Department of Electrical Engineering North China Electric Power University Baoding 071003 China Department of Applied Physics North China Electric Power University Baoding 071003 China Electronic and Computer Engineering Department Brunel University London UK

Using the quantum theory for a mesoscopic circuit based on the discretenes of electric charges, the finitedifference Schrodinger equation of the non-dlssipative mesoscopic inductance and capacity coupling circuit is achieved. The Coulomb blockade effect, which is caused by the discreteness of electric charges, is studied. Appropriately choose the components in the circuits, the finlte-dlfference Schrodinger equation can be divided into two Mathieu equations in representation.＂ With the WKBJ method, the currents quantum fluctuations in the ground states of the two circuits are calculated. The results show that the currents quantum zero-point fluctuations of the two circuits are exist and correlated.

关键词： mesoscopic circuit Mathieu equation quantum effect

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Vibrating-Sliding Motion of Caisson Breakwaters Under Various Breaking Wave Impact Forces

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China Ocean Engineering 2003年第4期18卷 565-576页

作者： WANG yuan-zhan(王元战) YU Hong-xia(于红霞) Department of Port and Coastal Engineering School of Civil Engineering Tianjin University Tianjin300072 China Department of Port and Coastal Engineering School of Civil Engineering Tianjin University Tianjin300072 China

Sliding is one of the principal failure types of caisson breakwaters and is an essential content of stability examination in caisson breakwater design. Herein, the mass-spring-dashpot model of caisson-base system is used to simulate the vibrating-sliding motion of the caisson under various types of breaking wave impact forces, i.e., single peak impact force, double peak impact force, and shock-damping oscillation impact force. The effects of various breaking wave impacts and the sliding motion on the dynamic response behaviors of caisson breakwaters are investigated and the calculation of relevant system parameters is discussed. It is shown that the dynamic responses of the caisson are significantly different under different types of breaking wave impact forces even when the amplitudes of impact forces are equal. The amplitude of dynamic response of the caisson is lower under single peak impact excitation than that under double peak impact or shock-damping oscillation impact excitation. Though the displacement of the caisson is large due to sliding, the rotation, the sliding force and the overturning moment of the caisson are significantly reduced.

关键词： breakwater various types of breaking wave impact vibrating-sliding motion

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Quantum Effect in Mesoscopic Open Electron Resonator

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Communications in Theoretical Physics 2008年第8期50卷 521-524页

作者： YAN zhan-yuan zhanG Xiao-Hong HAN Ying-Hui School of Mathematics and Applied Physics North China Electric Power University Baoding 071003 China

The open electron resonator is a mesoscopic device that has attracted considerable attention due to its remarkable behavior： conductance oscillations. In this paper, using an improved quantum theory to mesoscopic circuits developed recently by Li and Chen, the mesoscopic electron resonator is quantized based on the fundamental fact that the electric charge takes discrete value. With presentation transformation and unitary transformation, the SchrSdinger equation becomes an standard Mathieu equation. Then, the detailed energy spectrum and wave functions in the system axe obtained, which will be helpful to the observation of other characters of electron resonator. The average of currents and square of the current are calculated, the results show the existence of the current fluctuation, which causes the noise in the circuits, the influence of inductance to the noise is discussed. With the results achieved, the stability characters of mesoscopic electron resonator are studied firstly, these works would be benefit to the design and control of integrate circuit.

关键词： mesoscopic circuit Mathieu equation quantum effect

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A Test of Color-Octet Heavy Quarkonium Production Mechanism

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Communications in Theoretical Physics 2001年第11期36卷 569-572页

作者： DUAN Chun-Gui YAN zhan-yuan HE Zhen-Min CCAST World Laboratory P.O.Box 8730Beijing 100080China CCAST(World Laboratory) P.O.Box 8730Beijing 100080China Physics DepartmentNorth China Electric Power UniversityBaoding 071003China CCAST World LaboratoryP.O.Box 8730Beijing 100080China CCAST(World Laboratory) P.O.Box 8730Beijing 100080China

Using the scale evolution of nuclear parton distributions,the contribution of color-octet heavy quarkonium production mechanism to the P + Fe → J/ψ + γ + X process in calculated and *** our theoretical results with... 详细信息

关键词： nuclear parton distribution,color-octet,nonrelativistic QCD

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