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A new adaptive fast motion estimation algorithm based on local motion similarity degree (LMSD)

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Progress in Natural science:materials International 2005年第12期15卷 1126-1134页

作者： LIU Long,HAN Chongzhao and BAI Yan school of Electronics & Information engineering,xi’an {2. university,xi’an 710049,china school of Electronics and Information engineering Xi'an Jiaotong University Xi'an 710049 China

In the motion vector field adaptive search technique (MVFAST) and the predictive motion vector field adaptive search technique (PMVFAST),the size of the largest motion vector from the three adjacent blocks (left,top,top-right) is compared with the threshold to select different search *** a suitable search center and search pattern will not be selected in the adaptive search technique when the adjacent motion vectors are not coherent in local *** paper presents an efficient adaptive search *** motion vector variation degree (MVVD) is considered a reasonable factor for adaptive search *** the relationship between local motion similarity degree (LMSD) and the variation degree of motion vector (MVVD),the motion vectors are classified as three categories according to corresponding LMSD; then different proposed search schemes are adopted for motion *** experimental results show that the proposed algorithm has a significant computational speedup compared with MVFAST and PMVFAST algorithms,and offers a similar,even better performance.

关键词： motion estimation motion vector video coding local motion

A Mathematical Model for Predicting Shrinkage Defect of Ductile Iron Castings

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International Journal of Minerals,Metallurgy and materials 2000年第1期14卷 24-29页

作者： ZhiqiangHan Junyi Su Kaike Cai Metallurgy school, university of {2. and Technology Beijing, Beijing 100083, china xi’an jiaotong university, xi’an 710049, china Metallurgy school University of Science and Technology Beijing Beijing 100083 China xi'an jiaotong university Xi'an 710049 China

The shrinkage defect of a ductile iron casting is attributed to the volume variations occurring in solidification, which consist of liquid contraction, solidification shrinkage, graphitization expansion, and mold cavity enlargement. Based on this understanding, a mathematical model for predicting the shrinkage defect of the casting is developed, in which the volume variations of the casting in soli- dification are numerically simulated, especially, the mold cavity enlargement is quantitatively calculated. Moreover, the reliability of the model is verified in production and experiment.

关键词： ductile iron casting shrinkage defect mold cavity enlargement mathematical model

Binary particle swarm optimization with multiple evolutionary strategies

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science china(Information sciences) 2012年第11期55卷 2485-2494页

作者： ZHAO Jing1,HAN ChongZhao1 & WEI Bin2.1Ministry of Education Key Lab For Intelligent Networks and Network Security,State Key Laboratory for Manufacturing Systems engineering,Institute of Integrated Automation,school of Electronics and Information engineering,xi'an jiaotong university,xi'an 710049,china 2.nstitute of System engineering,school of Electronics and Information engineering,xi'an jiaotong university,xi'an 710049,china Ministry of Education Key Lab For Intelligent Networks and Network Security State Key Laboratory for Manufacturing Systems Engineering Institute of Integrated Automation School of Electronics and Information Engineering Xi’an Jiaotong University Xi’an China Institute of System engineering School of Electronics and Information Engineering Xi’an Jiaotong University Xi’an China

This paper introduces a novel variation of binary particle swarm optimization(BPSO) algorithm and a further extension to improve its ***,mimicking the behaviors of some creatures group,multiple evolutionary strategies BPSO(MBPSO) is introduced which takes different evolutionary strategies for various particles according to their ***,on the basis of MBPSO,a new strategy is discussed to improve the performance of the MBPSO(M2.PSO) which adopts the concept of the mutation operator aiming to overcome the premature convergence and slow convergent speed during the later stages of the *** proposed two algorithms are tested on seven benchmark functions and their results are compared with those obtained by other *** results show that our methods outperform the other algorithms.

关键词： binary particle swarm optimizer evolutionary strategies swarm intelligence

A quantum-confinement model for surrounding-gate MOSFETS from subthreshold to strong-inversion regions

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science china(Information sciences) 2012年第10期55卷 2399-2408页

作者： LIU LinLin & LI ZunChao school of Electronics and information engineering,xi’an {2. university,xi’an 710049,china school of Electronics and information engineering Xi’an Jiaotong University Xi’an China

A new analytical model is developed for quantum-confinement effects of short channel surroundinggate *** eigenenergies and wavefunctions are obtained by solving Schrdinger’s equation with an accurate potential energy *** potential energy distribution is derived from the solution of Poisson’s equation,which contains both depletion charge and free *** eigenenergies obtained from our model are compared with other two quantum-confinement models,which use flat-well approximation and parabola-well approximation as the potential energy distributions,*** we point out the relationship between the eigenenergies and the potential energy distribution for the first *** on this model,the electron density with quantum confinement effects are derived,and threshold voltage is defined based on average electron *** considering quantum confinement effects,the electron density becomes smaller while the threshold voltage becomes *** results show that this model is applicable from the subthreshold region to the stronginversion region in different channel doping conditions.

关键词： surrounding gate quantum-confinement effects potential energy MOSFET

Dry Friction Characteristics of Ti-6Al-4V Alloy under High Sliding Velocity

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Journal of Wuhan university of Technology(materials {2.) 2007年第4期22卷 582-585页

作者：邱明 school of Mechatronic engineering Henan University of Science and Technology Theory of Lubrication and Bearing Institute Xi'an Jiaotong UniversityXi'an 710049China

Tribological behaviours of Ti-6Al-4V alloy pins sliding against GCr15 steel discs over a range of contact pressures （0.33-1.33 MPa） and sliding velocities （30-70 m/s） were investigated using a pin-on-disc tribometer under unlubricated conditions. The wear mechanisms and the wear transition were analyzed based on examinations of worn surfaces using SEM, EDS and XRD. When the velocity increases, the friction coefficient and the wear rate of the Ti-6Al-4V alloy show typical transition features, namely, the critical values of sliding velocities for 0.33 and 0.67 MPa are 60 and 40 m/s, respectively. The experimental results reveal that the tribological behaviours of Ti-6Al-4V alloys are controlled by the thermal-mechanical effects, which connects with the friction heat and hard particles of the pairs. A tribolayer containing mainly Ti oxides and V oxides is formed on the worn surface of Ti-6Al-4V alloy.

关键词： Ti alloy dry sliding friction behavior contact temperature wear mechanism

A mathematical model for concept granular computing systems

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science china(Information sciences) 2010年第7期53卷 1397-1408页

作者： QIU GuoFang1, MA JianMin2. YANG HongZhi3 & ZHANG Wenxiu3 1school of Management, xi’an university of Architecture & Technology, xi’an 710055,{2. 2.aculty of science, Chang’an university, xi’an 710064,{2. 3Faculty of science, xi’an jiaotong university, xi’an 710049,{2. school of Management Xi’an University of Architecture & Technology Xi’an China Faculty of science Chang’an University Xi’an China Faculty of science Xi’an Jiaotong University Xi’an China

Extent-intent and intent-extent operators are introduced between two complete lattices in this paper and a mathematical model for concept granular computing system is established. We proved that the set of all concepts in this system is a lattice with the greatest element and the least element. This framework includes formal concept lattices from formal contexts, L fuzzy concept lattices from L fuzzy formal contexts and three kinds of variable threshold concept lattices, i.e. the extension and the intension of a concept are a crisp set and a crisp set, a crisp set and a fuzzy set, a fuzzy set and a crisp set, respectively. Finally, some iterative algorithms for constructing concepts are proposed and they are proved to be optimal concepts under some conditions in this system.

关键词： granular computing formal concept analysis concept lattice mathematical model

Cushioning Performance of a Novel Polyurethane Foam material Applied in Fragile Packaging

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Acta Mechanica Solida Sinica 2024年第3期37卷 487-497页

作者： Huifeng xi Chunqiu Guo Jinbiao Yang xiaogang Wang Bowei Wang Shiqing Huang Zhiwei Wang school of Mechanics and Construction engineering Jinan UniversityGuangzhou510632China College of Packing engineering Jinan UniversityZhuhai519070China MOE Key Lab of Disaster Forecast and Control in engineering Jinan UniversityGuangzhou510632China Foshan Soft Valley Technology Co. Ltd.Foshan528000China

For fragile products,packaging requires cushioning protection to prevent irreversible damage from accidental falls,transportation impacts,and other *** new polyurethane foam(PUF)material demonstrates superior cushioning and vibration isolation performance in practical applications,effectively minimizing damage from *** and vibration experiments were conducted on packages comprising novel PUF,expandable polyethylene,ethylene-vinyl acetate copolymer foam,and *** verify that the new PUF material outperforms in cushioning and vibration isolation,as observed from the acceleration ***,a random vibration analysis of a packaging unit involving different thicknesses of PUF materials and bracelets reveals the enhanced vibration isolation effect within a specific thickness *** vibration results of the bracelet’s outer packaging align closely with finite element simulation results,validating the effectiveness of designing and optimizing the outer *** finite element simulation,deeper understanding and prediction of the bracelet’s vibration response under various conditions is achieved,facilitating optimized packaging design for better protection and vibration damping.

关键词： Flexible polyurethane foam Packaging of fragile goods Nonlinear dynamics Vibration frequency Finite element simulation

Analysis of Microstructure and Orientation in X80 Line Pipe Steels

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Journal of Iron and Steel Research International 2011年第S1期18卷 664-668页

作者： JI Ling-kang 1,2.LI Yang 2.3,MENG Li 3,LI He-lin 2.(1.school of material {2. and engineering,xi’an jiaotong university,xi’an 710049,Shaanxi,china 2.CNPC Tubular Goods Research Institute,xi’an 710065,Shaanxi,china 3.school of material {2. and engineering,university of {2. and Technology Beijing,Beijing 100083,china) xi An Jiao Tong Univ Sch Mat Sci & Engn Xian 710049 Shaanxi Peoples R China CNPC Tubular Goods Res Inst Xian 710065 Shaanxi Peoples R China Univ Sci & Technol Beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China

Microstructures in X80 line pipe were classified by SEM *** experimental results showed that the microstructures in X 80 line pipe steels were complicated consisting of polygonal ferrite,bainite and acicular *** relation within acicular ferrite was investigated systematically by means of *** sub-structures were observed maximum in acicular ferrite which gives high strength and high toughness to line pipe *** K-S orientation relation was generally observed between acicular ferrite and austenite during phase *** low energy CSL boundary characterized by Σ3 orientation relation according to Brandon criterion appeared with higher probability,which was benefit to improve the mechanical properties of line pipe *** orientations or texture of initial austenite grains could be deduced based on the Σ3 orientation relationship of acicular ferrite variants.

关键词： acicular ferrite EBSD K-S orientation relation TMCP

High-precision parallel computing model of solute transport based on GPU acceleration

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Journal of Hydrodynamics 2024年第1期36卷 202-212页

作者： Shang-hong Zhang Rong-qi Zhang Wen-da Li xi-yan Yang Yang Zhou school of Water Resources and Hydropower engineering North China Electric Power UniversityBeijing102206China Hubei Key Laboratory of Intelligent Yangtze and Hydroelectric science China Yangtze Power Co.Ltd.Yichang443133China

The scenario simulation analysis of water environmental emergencies is very important for risk prevention and control,and emergency *** quickly and accurately simulate the transport and diffusion process of high-intensity pollutants during sudden environmental water pollution events,in this study,a high-precision pollution transport and diffusion model for unstructured grids based on Compute Unified Device Architecture(CUDA)is *** finite volume method of a total variation diminishing limiter with the Kong proposed r-factor is used to reduce numerical diffusion and oscillation errors in the simulation of pollutants under sharp concentration conditions,and graphics processing unit acceleration technology is used to improve computational *** advection diffusion process of the model is verified numerically using two benchmark cases,and the efficiency of the model is evaluated using an engineering *** results demonstrate that the model perform well in the simulation of material transport in the presence of sharp ***,it has high computational *** acceleration ratio is 46 times the single-thread acceleration effect of the original *** efficiency of the accelerated model meet the requirements of an engineering application,and the rapid early warning and assessment of water pollution accidents is achieved.

关键词： Pollution transport and diffusion model parallel computing Compute Unified Device Architecture(CUDA) pollution event