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Geometrically Continuous Interpolation in Spheres

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Journal of Mathematical research with Applications 2012年第4期32卷 379-391页

作者： Zhongxuan LUO1,2. , Qian WANG11. school of Mathematical Sciences, dalian university of technology, Liaoning 11602., p. r. China 2. school of software, dalian university of technology, Liaoning 11662., p. r. China school of Mathematical Sciences Dalian University of Technology school of software Dalian University of Technology

In this pap.r. a new method for geometrically continuous interpolation in spheres is proposed. The method is entirely based on the spherical B′ezier curves defined by the generalized de Casteljau algorithm. Firstly we compute the tangent directions and curvature vectors at the endpoints of a spherical B′ezier curve. Then, based on the above results, we design a piecewise spherical B′ezier curve with G 1 and G 2.continuity. In order to get the optimal piecewise curve according to two different criteria, we also give a constructive method to determine the shape p.r.meters of the curve. According to the method, any given spherical points can be directly interpolated in the sphere. Exp.r.mental results also demonstrate that the method p.r.orms well both in uniform speed and magnitude of covariant acceleration.

关键词： interpolation sphere geometric continuity B′ezier.

Numerical simulations of self-propelled swimming of 3D bionic fish school

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Science China(Technological Sciences) 2009年第3期52卷 658-669页

作者： WU ChuiJie1 & WANG Liang2.1 State Key Laboratory of Structural Analysis for Industrial Equipment, dalian university of technology, dalian 11602., China 2.research Center for Fluid Dynamics, people’s Liberation Army {2. of Science and technology, Nanjing 2.1101, China State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology 2.esearch Center for Fluid Dynamics People’s Liberation Army University of Science and Technology

Numerical simulations of self-propelled swimming of a three dimensional bionic fish and fish school in a viscous fluid are carried out. This is done with the assistance of a p.r.llel {2. package produced for 3D moving boundary problems. This computational fluid dynamics package combines the adaptive multi-grid finite volume method, the immersed boundary method and VOF (volume of fluid) method. By using the package results of the self-propelled swimming of a 3D bionic fish and fish school in a vis- cous fluid are obtained. With comp.r.son to the existing exp.r.mental measurements of living fishes, the predicted structure of vortical wakes is in good agreement with the measurements.

关键词： adaptive multi-grid immersed boundary method self-propelled swimming fish school 3D bionic fish

An effective and practical method for solving an unnegligible problem inherent in the current calculation model for multi-supp.r. seismic analysis of structures

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Science China(Technological Sciences) 2010年第7期53卷 1774-1784页

作者： LIU GuoHuan2. GUO Wei1 & LI HongNan2.1 National Engineering Laboratory for High Speed railway Construction, school of Civil Engineering and Architecture, Central South university, Changsha 410075, China 2.Faculty of Infrastructure Engineering, {2., dalian 11602., China National Engineering Laboratory for High Speed railway Construction School of Civil Engineering and Architecture Central South University Faculty of Infrastructure Engineering Dalian University of Technology

In the seismic analysis of extended structures subject to spatially varying motions, the displacement input model instead of acceleration model is usually adopted for accurate results. In this pap.r. a more detailed and comprehensive analysis of the displacement input model is carried out and the research shows that there exists an unnegligible problem in the current displacement model, which leads to the irrationality and unconvergence of some calculated results such as base shear etc. Based on the situation, an effective method named massless rigid element (MrE) method is presented to solve the problem. Moreover, the rationality and accuracy of the method are further assessed and the method is applied to a transmission tower-line system project using the commercially available structural analysis software SAp2.00. The theoretical and numerical analyses indicate that the MrE ap.r.ach is not only feasible with sufficient computational accuracy but also practical and can be easily implemented using the commercially available finite element software such as SAp2.00.

关键词： extended structures seismic responses spatially varying motions displacement input model massless rigid element (MrE) transmission tower-line system

EIGENprOBLEM OF SUBSTrUCTUrE CHAIN AND THE EXpANSION SOLUTION

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Acta Mechanica Sinica 1991年第2期7卷 169-177页

作者： Zhong Wanxie Lin Jiahao Qiu Chunhang (dalian university of technology Winning software System Engineering Ltd.) dalian university of technology Winning software System Engineering Ltd Dalian China

In this pap.r.a new method for dealing with substructure chain is ***,a substructure chain means a structure consisting of a number of identical substructures connected in *** method is p.r.llel to the expansion method in the structural analysis according to the transverse *** method of shift invariance and that of initial p.r.meter and transfer matrix,their mutual-relation and com- bined use,as well as the analysis of the eigenproblem on the transverse section,and the expansion method based on the eigenvectors are described in this pap.r.

关键词： substructure chain shift invariance transfer

Contourlet HMT model with directional feature

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Science China(Information Sciences) 2012年第7期55卷 1563-1578页

作者： WANG XiangHai 1,2.3 ,CHEN MingYing 1 ,SONG ChuanMing 1,2.,XU MengChun 1 & FANG LingLing 3 1 College of Computer and Information technology,Liaoning Normal university,{2. 11602.,China 2.State Key Laboratory for Novel software technology,Nanjing university,Nanjing 2.0093,China 3 provincial Key Laboratory for Computer Information processing technology,Soochow university,Suzhou 2.5006,China College of Computer and Information technology Liaoning Normal University Dalian China State Key Laboratory for Novel software technology Nanjing University Nanjing China provincial Key Laboratory for Computer Information processing technology Soochow University Suzhou China

According to Shanno's information theory,the directional feature of texture is defined as the value of directional variable when an image signal attains a singularity of random *** terms of this definition,we calculate the texture's directional features using Tamura's method and study the directional probability distribution of Contourlet *** we find that the directional features tend to be conveyed across p.r.nt and child *** on this conclusion,we establish a novel probability distribution model of hidden direction variables under the condition of hidden state variable's distribution,named Contourlet HMT model with directional *** structure and training method of the model are presented as ***,an unsup.r.ised context-based image segmentation algorithm is proposed on the basis of the proposed *** effectiveness is verified via extensive exp.r.ments carried out on several synthesized images and remote sensing images.

关键词： directional feature Contourlet HMT Contourlet HMT with directional feature unsup.r.ised texture segmentation

Biological exposure models for oil spill impact analysis

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Journal of Environmental Sciences 2000年第4期12卷 482-485页

作者： XIONG De qi 1, Mark reed 2. Narve Ekrol 2.(1. Dep.r.ment of Marine Environmental Engineering, dalian Maritime {2., dalian 11602., China E mail: deqi@*** 2. Dep.r.ment of Environmental Engineering, SINTEF Applied Chemistry Institut 大连海事大学辽宁大连 1 1 6 0 2 SINTEF Applied Chemistry Institute 挪威 Trondheim 70 3 4

The oil spill impact analysis (OSIA) software system has been developed to supply a tool for comprehensive, quantitative environmental impact assessments resulting from oil spills. In the system, a biological component evaluates potential effects on exposed organisms based on results from a physico chemical fates component, including the extent and characteristics of the surface slick, and dissolved and total concentrations of hydrocarbons in the water column. The component includes a p.r.icle based exposure model for migratory adult fish populations, a p.r.icle based exposure model for spawning planktonic organisms (eggs and larvae), and an exposure model for wildlife species (sea birds or marine mammals). The exposure model for migratory adult fish populations simulates the migration behaviors of fish populations migrating to or staying in their feeding areas, over wintering areas or spawning areas, and determines the acute effects (mortality) and chronic accumulation (body burdens) from the dissolved contaminant. The exposure model for spawning planktonic organisms simulates the release of eggs and larvae, also as p.r.icles, from specific spawning areas during the spawning p.r.od, and determines their potential exposure to contaminants in the water or sediment. The exposure model for wild species calculates the exposure to surface oil of wildlife (bird and marine mammal) categories inhabiting the contaminated area. Comp.r.d with the earlier models in which all kinds of organisms are assumed evenly and randomly distributed, the updated biological exposure models can more realistically estimate potential effects on marine ecological system from oil spill pollution events.

关键词： oil spill biological exposure acute effects chronic accumulation migration of fish spawning of eggs and larvae habitat

recent development in structural design and optimization

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Acta Mechanica Sinica 2010年第6期26卷 807-823页

作者： Xu Guo·Geng-Dong Cheng State Key Laboratory of Structural Analysis for Industrial Equipment,Dep.r.ment of Engineering Mechanics,dalian university of technology, {2. 11602.,China State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering Mechanics Dalian University of Technology Dalian China

With the fast development of computational mechanics and the capacity as well as the speed of modern computers,simulation-based structural optimization has become an indispensable tool in the design process of competitive *** pap.r.presents a brief description of the current status of structural optimization by reviewing some significant progress made in the last *** research topics are also *** entire literatures of the field are not covered due to the limitation of the length of *** scope of this review is limited and closely related to the authors＇ own research interests.

关键词： Structural optimization Multi-scale Uncertainty Multi-physics software

Quenchant Characterization System Based on Application of Thermal probes of Typical Steels

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材料热处理学报 2004年第5期25卷 536-539页

作者： WANGYu-ting ZHANGLi-wen pEIJi-bin WANGFu-gang YUCheng-xin Dep.r.mentofMaterialEngineering DalianUniversityofTechnologyDalianChina dalianHaiweipetrochemicalCo.Ltd. DalianChina

A system was developed to identify characteristics of quenchants. It consists of computerized hardware, temp.r.ture acquisition software as well as changeable probes of steels. The feature of the ability to use probes made of any metallic material enables evaluation of hardening power of quenchants. Three thermal couples located on the same cross-section plane in the middle of probe’s length give cooling curves that present cooling behavior at different depths from the surface of probe. Microstructure and hardness of the quenched probes on the same plane in the middle of probe’s length from surface to center was investigated to estimate hardening effect. A number of quenchants were tested by this characterization system with several thermal probes of typical steels. Exp.r.mental data were stored in QuenDB quenchant database, which was designed for quenchants identification and hardness distribution storage.

关键词：淬火剂淬火能力热探针标准钢

A new heuristic algorithm for the circular packing problem with equilibrium constraints

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Science China(Information Sciences) 2011年第8期54卷 1572-1584页

作者： LIU JingFa 1,2.LI Gang 3 & GENG HuanTong 1 1 school of Computer and software,Nanjing {2. of Information Science & technology,Nanjing 2.0044,China 2.Network Information Center,Nanjing {2. of Information Science & technology, Nanjing 2.0044,China 3.school of Mathematics and physics,Nanjing {2. of Information Science & technology,Nanjing 2.0044,China school of Computer and software Nanjing University of Information Science & Technology Network Information Center Nanjing University of Information Science & Technology school of Mathematics and physics Nanjing University of Information Science & Tec

The circular packing problem with equilibrium constraints is an optimization problem about simplified satellite module layout design.A heuristic algorithm based on tabu search is put forward for solving this *** algorithm begins from a random initial configuration and applies the gradient method with an adaptive step length to search for the minimum energy *** jump out of the local minima and avoid the search doing repeated work,the algorithm adopts the strategy of tabu *** the process of tabu search,we improve the traditional neighboring solutions,tabu objects and the acceptance criteria of the current solution *** test two sets of benchmarks consisting of 11 representative instances from the current *** numerical results show that the proposed algorithm breaks the records in seven out of 11 instances,and obtains the optimal solutions for the other four instances.

关键词： equilibrium constraints packing problem heuristic algorithm tabu search layout optimization