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Image stylization with enhanced structure on GPU

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science china(Information sciences) 2012年第5期55卷 1093-1105页

作者： LI Ping 1,SUN HanQiu 1,SHENG Bin 1,2 & SHEN JianBing 3 1 Department of computer science and engineering,The Chinese university of Hong Kong,Hong Kong,china 2 Department of computer science and engineering,shanghai Jiao Tong university,shanghai 200240,china 3 school of computer science and Technology,Beijing Institute of Technology,Beijing 100081,china Department of computer science and engineering The Chinese University of Hong Kong Hong Kong China Department of computer science and engineering Shanghai Jiao Tong University Shanghai China school of computer science and Technology Beijing Institute of Technology Beijing China

This paper presents a graphics processing unit (GPU) based stylization approach that preserves the fine structure between the original and the stylized images using gradient *** abstraction and painterly stylization methods focused on contrast manipulation only,and thus the detailed salient structures of the input images are always destroyed when performing the current stylization techniques because of limitations like unavoidable salience information loss caused by contrast *** propose an image structure map to naturally model the fine structure existing in the original ***-based structure tangent generation and tangent-guided image morphology are used to construct the structure *** image structure map,unlike an edge map,not only systematically models the boundary information within the imagery but also accentuates the underlying inner structure detail for further *** facilitate the final stylization via parallel bilateral grid and structure-aware stylizing optimization on a GPU-CUDA platform in real *** multiple experiments,the proposed method consistently demonstrates efficient and high quality image stylization performance.

关键词： image stylization non-photorealistic rendering real-time processing GPU image abstraction

Modification mechanism of cerium on the Al-18Si alloy

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Rare Metals 2006年第1期25卷 11-15页

作者： ZHANG Henghua DUAN Haili SHAO Guangjie XU Luoping YIN Junlin YAN Biao school of Materials science and engineering Shanghai University Shanghai 200072 China school of Materials science and engineering Tongji University Shanghai 200092 China

The effect of the rare earth cerium （Ce） on the hypereutectic Al-Si alloy under different casting states have been studied by optical microscope and quantitative image analysis. It is found that the size and the quantity of primary silicon in castings decrease with the increase of added Ce in the melt. Meanwhile primary silicon changes from branched shape to fine facetted shape. Although the modification on eutectic silicon in castings also improves with the increase of added Ce in the melt, the effect of modification on eutectic silicon away from primary silicon is more obvious than that on eutectic silicon close to primary silicon. The modification mechanism was analyzed in detail by means of scanning electron microscope equipped with energy dispersive analysis of X-ray and thermodynamics analysis, which included the analysis on the change in standard Gibbs energy of reaction and reaction equilibrium.

关键词： metal material modification mechanism thermodynamics analysis rare earth element hypereutectic Al-Si alloy

Efficient video cutout based on adaptive multilevel banded method

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science china(Information sciences) 2012年第5期55卷 1082-1092页

作者： CHEN MinGang 1,SUI BoCong 1,GAO Yan 2 & MA LiZhuang 1 1 Department of computer science and engineering,shanghai Jiao Tong university,shanghai 200240,china 2 Software engineering Institute,East china Normal university,shanghai 200062,china Department of computer science and engineering Shanghai Jiao Tong University Shanghai China Software engineering Institute East China Normal University Shanghai China

Although many efficient image cutout approaches have been proposed,it is still a challenge to cut out foreground objects from a video clip because of the costs of time and memory consumption and the difficulty in maintaining temporal coherence for the cutout *** this paper,we propose a novel and efficient video cutout approach by extending a multilevel banded image segmentation method to video *** our method,the segmentation results are propagated frame by frame at the lowest resolution level based on optical flow,and are refined in image pyramids level by level through banded graph *** construct an adaptive narrow band to ensure that the segmentation result falls exactly into the narrow band during *** results show that the video cutout approach based on adaptive multilevel bands dramatically reduces time and memory costs,and achieves ideal segmentation results.

关键词： video object cutout multilevel band graph cuts video segmentation

A STEEL MATRIX WEAR RESISTANT COMPOSITE REINFORCED BY IN-SITU GRANULAR EUTECTICS

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Acta Metallurgica Sinica(English Letters) 2001年第2期14卷 79-84页

作者： Z.M. Xu, T.X. Li and J.G. Li (school of Materials science and engineering, shanghai Jiao Tong university, shanghai 200030, china) Sch. of Mat. Sci. and Eng. Shanghai Jiaotong Univ. Shanghai 200030 China

A new steel matrix wear resistant composite reinforced by in situ granular eutectics can be obtained by modifying with a Si-Ce-Ti compound in the steel melt. The result indicates that the in situ granular eutectic is a pseudo-eutectic of austenite and (Fe,Mn)3C, which is formed between austenite dendrites during solidification due to the segregation of C and Mn impelled by modifying elements. The quantity of in situ granular eutectic reaches up to 8%-12% and its grain size is in the range from 10um to 20um. The austenite steel matrix wear resistant composite reinforced by in situ granular eutectic (abbreviated AGE composite) and austenite-bainite steel mains wear resistant composite reinforced by in situ granular eutectic (abbreviated ABGE composite) are obtained in the as-cast state and by air hardening, respectively. The wear resistance of the AGE and ABGE composites can be more greatly increased than that of their matrix steels under low and medium impact working condition.

关键词： steel matrix composite Si-Ce-Ti compound in situ granular eutectic mechanical property

Experimental Study on Turbulent Structure of Humid Air Flame in a Bluff-body Burner

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Journal of Thermal science 2009年第2期18卷 185-192页

作者： Bing Ge Shu-Sheng Zang Pei-qing Guo school of Mechanical engineering, shanghai Jiao Tong university, shanghai 200240, china 800, Dong Chuan Road, shanghai, china. Zip: 200240 school of Mechanical engineering Shanghai Jiao Tong University Shanghai China shanghai China

The main objective of the present experimental study is to analyze the turbulent structure in humid airnon-premixed flame, and determine the effect of humidity on the flow field and the flame stability limit in turbulentnon-premixed flame. Particle Image Velocimetry (PIV) is used to capture the instantaneous appearance ofvortex structures and obtain the quantitative velocity field. The distributions of Reynolds shear stress, mean androot-mean squared fluctuating (rms) velocities are examined to get insight into the effect of fuel-to-air velocity ratioon velocity flow field. The results show that with steam addition, the air-driven vortex in the bluff-body wakeis thinner; the biggest peaks of rms velocity and Reynolds shear stress are lower; the distance between the peaksof rms velocity on the sides of centerline reduces. Besides these, the flame stability is affected. Both central fuelpenetration limit and partially quenching limit reduce with steam addition.

关键词： humid air combustion turbulence measurement PIV

Microstructure of Cu_(60)Zr_(20)Ti_(20) bulk metallic glass rolled at different strain rates

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science china(Physics,Mechanics & Astronomy) 2008年第4期51卷 394-399页

作者： LI JinFu,CAO QingPing & ZHOU YaoHe State Key Laboratory of Metal Matrix Composites,school of Materials science and engineering,shanghai Jiao Tong university,shanghai 200030,china State Key Laboratory of Metal Matrix Composites School of Materials Science and Engineering Shanghai Jiao Tong University Shanghai China

The structural evolution of Cu60Zr20Ti20 bulk metallic glass during rolling at different strain rates and cryogenic temperature was investigated by X-ray diffraction (XRD),differential scanning calorimetry (DSC) and high-resolution transmission electron microscopy (HRTEM). It is revealed that the deformation-induced transformation is strongly dependent on the strain rate. At the lowest experimental strain rate of 1.0×10-4 s-1,no phase transformation occurs until the highest deformation degree reaches 95%. In a strain rate range of 5.0×10-4-5.0×10-2 s-1,phase separation oc-curs in a high deformation degree. As the strain rate reaches 5.0×10-1 s-1,phase separation and nanocrystallization concur. The critical deformation degree for oc-currence of phase transformation decreases with the strain rate increasing.

关键词： metallic glass inhomogeneous deformation strain rate phase separation nanocrystallization

On Sequential Composition of Precise Zero-Knowledge

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Journal of shanghai Jiaotong university(science) 2010年第1期15卷 43-48页

作者：丁宁谷大武 Department of computer science and engineering Shanghai Jiaotong University

Precise zero-knowledge was introduced by Micali and Pass in STOC'*** notion captures the idea that the view of any verifier in interaction can be reconstructed in almost *** also obtained a sequential composition lemma for precise zero-knowledge ***,this lemma doesn't provide tight precisions for composed *** this paper we further obtain a sequential composition lemma for a subclass of precise zero-knowledge protocols,which all satisfy a property:their simulators use the code of verifier in almost the black-box *** call such subclass emulated black-box zero-knowledge *** lemma provides better precisions for sequential composition of such protocols.

关键词： cryptography zero-knowledge precise zero-knowledge

A NEW NUMERICAL METHOD FOR GROUNDWATER FIOW AND SOLUTE TRANSPORT USING VELOCITY FIELD

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Journal of Hydrodynamics 2008年第3期20卷 356-364页

作者： ZHANG Qian-fei LAN Shou-qi WANG Yan-ming XU Yong-fu school of Naval Architecture Ocean and Civil Engineering Shanghai Jiaotong University Shanghai 200030China shanghai Municipal engineering Design Institute Shanghai 200092 China Department of Geotechnical engineering Tongji University Shanghai 200092 China

A new numerical method for groundwater flow analysis was introduced to estimate simultaneously velocity vectors and water pressure head. The method could be employed to handle the vertical flow under variably saturated conditions and for horizontal flow as well. The method allows for better estimation of velocities at the element nodes which can be used as direct input to transport models. The advection-dispersion process was treated by the Eulerian-Lagrangian approach with particle tracking technique using the velocities at FEM nodes. The method was verified with the classical one dimensional model and applied to simulate contaminant transport process through a slurry wall as a barrier to prevent leachate pollution from a sanitary landfill.

关键词： groundwater flow solute transport velocity vectors finite element method Eulerian-Lagrangian approach particletracking technique

Effect of Polypropylene Fibers on the Long-term Tensile Strength of Concrete

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Journal of Wuhan university of Technology(Materials science) 2007年第1期22卷 52-55页

作者：姚武 school of Materials science and engineering Tongji University

The influence of low volume fraction of polypropylene（PP） fibers on the tensile properties of normal and high strength concretes was studied. The experimental results indicate that the addition of PP fibers in concrete leads to a reduction in tensile strength during the age of 28 d. Whereas, after 28 days, there is a notable effect in tensile strength due to PP fibers restraining the formation and growth of microcracks in concrete, which improves the continuity and integrality of concrete structure, Thus, a low volume fraction of PP fibers is beneficial to enhancing the long-term tensile strength of concrete materials and improving the durability of concrete structures.

关键词： polypropylene fiber concrete tensile strength microcrack