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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 1. Department of computer science and engineering The Chinese University of Hong Kong Hong Kong China2. Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China3. School of Computer Science and Technology Beijing Institute of Technology Beijing 100081 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

The Young's moduli prediction of random distributed short-fiber-reinforced polypropylene foams using finite element method

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science China(Technological sciences) 2009年第1期52卷 72-78页

作者： WANG Bo1, WANG RongXiu2 & WU Yong1 1 school of mathematic science, Chongqing Institute of Technology, Chongqing 400050, China 2 Department of computer science and Information engineering, Chongqing Technology and Business University, Chongqing 400067, China school of mathematic science Chongqing Institute of Technology Chongqing 400050 China Department of computer science and Information engineering Chongqing Technology and Business University Chongqing 400067 China

The elastic moduli of short-fiber-reinforced foams depend critically on the fiber content and fiber length, as well as on the fiber orientation distribution. Based on periodic tetrakaidecahedrons, the finite element models with short-fiber reinforcement were proposed in this paper to examine the effects of the fiber content and fiber length on Young's modulus. The fiber length distribution and fiber orientation distribution were also considered. The proposed models featured in a three-dimensional diorama with random short-fiber distribution within or on the surfaces of the walls and edges of the closed-cells of polypropylene (PP) foams. The fiber length/orientation distributions were modeled by Gaussian prob-ability density functions. Different fiber volume fractions, different lengths, and different distributions were investigated. The predicted Young's moduli of the PP foams with short-glass-fiber or short-carbon-fiber reinforcement were compared with other theoretic and experimental results, and the agreement was found to be satisfactory. The proposed finite element models were proved to be acceptable to predict the Young's moduli of the grafted closed-cell PP foams with short-fiber reinforcement.

关键词： short-fiber reinforcement Young’s modulus finite element Gaussian distribution

A community-centric approach to automated service composition

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science China(Information sciences) 2010年第1期53卷 50-63页

作者： LIU XuanZhe1,2, HUANG Gang1,2 & MEI Hong1,2 1school of Electronics engineering and computer science, Peking University, Beijing 100871, China 2Key Laboratory of High Confidence Software Technologies, Ministry of Education, Peking University, Beijing 100871, China 1. school of Electronics engineering and computer science Peking University Beijing 100871 China2. Key Laboratory of High Confidence Software Technologies Ministry of Education Peking University Beijing 100871 China

In the recent years, the web has kept growing rapidly and undergone tremendous changes towards a user-centric environment. With the proliferation of services available on the Internet, millions of users are able to voluntarily participate in and collaborate for their own interests and benefits by means of service composition. However, due to the ever increasing number of services, it then becomes a challenging issue to enable the users to rapidly select and compose the proper services. In this paper, we propose an approach which utilizes service communities for automated service composition. This paper makes three contributions. Firstly, we propose the service community architecture and identify two key components to facilitate service discovery and composition. Secondly, assisted by the service community, we provide two composition types to help users explore the space of potential composition opportunities without having to understand too many details of individual candidate services. Finally, we evaluate our approach by performance analysis and provide a web-based prototype that lowers the entry barrier for the users.

关键词： services computing service composition service community

Complex conforming Delaunay triangulation

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science China(Information sciences) 2010年第6期53卷 1130-1140页

作者： MENG XianHai 1, LI JiGang 1, YANG Qin 1, CAI Qiang 2 & CHEN QiMing 3 1 NLSDE, school of computer science and engineering, BeiHang University, Beijing 100083, China 2 school of computer sciences, Beijing Technology and Business University, Beijing 100037, China 3 school of Mechanical engineering and Automation, BeiHang University, Beijing 100083, China 1. NLSDE School of Computer Science and Engineering BeiHang University Beijing 100083 China2. School of Computer Sciences Beijing Technology and Business University Beijing 100037 China3. School of Mechanical Engineering and Automation BeiHang University Beijing 100083 China

A novel algorithm of conforming Delaunay triangulation for curved geometry is presented in the paper.A progress has been made for the problem puzzled Delaunay refinement where curved constraints cannot be accepted as input *** algorithm is based on a new sufficient condition for the existence of constraints in *** requires computing only the intersection between constraints and Voronoi edges or faces instead of the circum-sphere of curved *** the termination of the algorithm when small input angles exist in constraints, a weighted method is applied to ensure that the algorithm can terminate under any *** two-dimensional and three-dimensional results are also *** is shown that the algorithm has the capability of dealing with both linear and nonlinear constraints in a consistent way, without the need of maintaining triangular meshes on face constraints.

关键词： mesh generation Delaunay triangulation conforming curved constraints tetrahedralization weight

An interpolating boundary element-free method (IBEFM) for elasticity problems

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science China(Physics,Mechanics & Astronomy) 2010年第4期53卷 758-766页

作者： REN HongPing 1 , CHENG YuMin 2 & ZHANG Wu 1 1 school of computer engineering and science, Shanghai University, Shanghai 200072, China 2 Shanghai Institute of Applied mathematics and Mechanics, Shanghai University, Shanghai 200072, China 1. school of computer engineering and science Shanghai University Shanghai 200072 China2. Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China

The paper begins by discussing the interpolating moving least-squares (IMLS) method. Then the formulae of the IMLS method obtained by Lancaster are revised. On the basis of the boundary element-free method (BEFM), combining the boundary integral equation method with the IMLS method improved in this paper, the interpolating boundary element-free method (IBEFM) for two-dimensional elasticity problems is presented, and the corresponding formulae of the IBEFM for two-dimensional elasticity problems are obtained. In the IMLS method in this paper, the shape function satisfies the property of Kronecker δ function, and then in the IBEFM the boundary conditions can be applied directly and easily. The IBEFM is a direct meshless boundary integral equation method in which the basic unknown quantity is the real solution to the nodal variables. Thus it gives a greater computational precision. Numerical examples are presented to demonstrate the method.

关键词： moving least-squares (MLS) approximation interpolating moving least-squares (IMLS) method boundary integral equation meshless method boundary element-free method (BEFM) interpolating boundary element-free method (IBEFM) elasticity problem

Asymptotic SEP of MIMO beamforming in two-hop AF relaying systems

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science China(Information sciences) 2012年第2期55卷 377-383页

作者： FU YouHua1,HAN YuJie2,YANG LvXi2,ZHU WeiPing3 & LIU Chen1 1school of Electronic science and engineering,Nanjing University of Posts and Telecommunications,Nanjing 210003,China 2school of Information science and engineering,Southeast University,Nanjing 210096,China 3Department of Electrical and computer engineering,Concordia University,Montreal H3G 1M8,Canada 1. school of Electronic science and engineering Nanjing University of Posts and Telecommunications Nanjing 210003 China2. School of Information Science and Engineering Southeast University Nanjing 210096 China3. Department of Electrical and Computer Engineering Concordia University Montreal H3G 1M8 Canada

This paper derives an asymptotic average symbol error probability(SEP)expression for multiple-input multiple-output(MIMO)two-hop amplify-and-forward(AF)relay systems with optimal *** analysis at high signal-to-noise ratio(SNR)quantifies the diversity order and array gain,which are valid for any antenna numbers of the terminals and arbitrary channel fading *** is also proved that the system performance is dominated by the relatively degraded one of the two-hop *** results based on the simple expressions provide valuable insights into the performance and practical design considerations of MIMO AF networks.

关键词： MIMO relay networks optimal beamforming symbol error probability(SEP) diversity order

Surface-phonon-polariton-enhanced photoinduced dipole force for nanoscale infrared imaging

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National science Review 2024年第5期11卷 227-235页

作者： jian Li Junghoon Jahng Xuezhi ma Jing Liang Xue Zhang Qianhao Min Xiao-Liang Wang Shuangjun Chen Eun Seong Lee Xing-Hua Xia State Key Lab of Analytical Chemistry for Life science School of Chemistry and Chemical Engineering Nanjing University Hyperspectral Nano-Imaging Team Korea Research Institute of Standards and Science Institute of materials Research and engineering Agency for ScienceTechnology and Research College of materials science and engineering Nanjing Tech University

The photoinduced dipole force(Pi DF) is an attractive force arising from the Coulombic interaction between the light-induced dipoles on the illuminated tip and the sample. It shows extreme sample-tip distance and refractive index dependence, which is promising for nanoscale infrared(IR) imaging of ultrathin samples. However, the existence of Pi DF in the mid-IR region has not been experimentally demonstrated due to the coexistence of photoinduced thermal force(Pi TF), typically one to two orders of magnitude higher than Pi DF. In this study, we demonstrate that, with the assistance of surface phonon polaritons, the Pi DF of c-quartz can be enhanced to surpass its Pi TF, enabling a clear observation of Pi DF spectra reflecting the properties of the real part of permittivity. Leveraging the detection of the Pi DF of phonon polaritonic substrate, we propose a strategy to enhance the sensitivity and contrast of photoinduced force responses in transmission images, facilitating the precise differentiation of the heterogeneous distribution of ultrathin samples.

关键词： surface phonon polariton photoinduced dipole force nanoscale infrared imaging ultrathin sample

Reducing the vacancies associated with ferroelectric polarization to promote photocatalytic overall water splitting

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science China Chemistry 2024年第10期67卷 3258-3264页

作者： Haozhi Qi Yuyang Kang jian-An Liu Lichang Yin Wenyu Zhang Shangyi ma jianhang Qiu Lingli Li Weijin Hu Lianzhou Wang Gang Liu Institute of Metal Research Chinese Academy of SciencesShenyang 110016China school of materials science and engineering University of Science and Technology of ChinaShenyang 110016China Nanomaterials Centre School of Chemical Engineering and Australian Institute for Bioengineering and NanotechnologyThe University of QueenslandSt LuciaBrisbane QLD 4072Australia

Ferroelectric materials hold great promise in photocatalytic water splitting because their built-in electric field induced by the depolarization field can fulfill the separation of photogenerated ***,a number of intrinsic charged vacancy defects are simultaneously generated to screen the depolarized field for stabilizing the crystal structure,always resulting in severe recombination of photogenerated carriers and thus poor overall water splitting ***,we proposed a strategy to promote the separation and transport of photogenerated carriers of ferroelectric photocatalysts by adjusting the ferroelectric polarization and altering the coordination environment of elements to reduce the defect ***,we prepared a series of Ta-doped PbTiO_(3)with low Pb(V_(Pb))and O(V_(O))vacancy concentrations by reducing the polarization intensity and strengthening the Pb–O *** Ta-doped PbTiO_(3)shows efficient charge separation and greatly enhanced photocatalytic overall water splitting activity with the assistance of *** work highlights the importance of regulating ferroelectric polarization and vacancy defect concentration by the doping strategy in charge separation for photocatalytic water splitting.

关键词： PbTiO_(3) ferroelectric polarization vacancy defect element doping photocatalytic overall water splitting

Effect of heat treatment on microstructural evolution,mechanical properties and tribological properties of H13 steel prepared using selective laser melting

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Journal of Iron and Steel Research International 2024年第5期31卷 1246-1259页

作者： Li-xiong Han Yan Wang Shi-feng Liu Zhao-hui Zhang Wei Liu Xin Yang Dang-shen ma jian Zhou Ying-kang Wei College of Metallurgical engineering Xi’an University of Architecture and TechnologyXi’an710055ShaanxiChina Zhejiang University City College Hangzhou310015ZhejiangChina China Iron and Steel Research Institute Group Co. Ltd.Beijing100081China

H13 tool steel was successfully prepared by selective laser melting(SLM)*** effects of heat treatment on the microstructure,mechanical properties,and tribological properties of SLMed H13 steel were *** heat treatment process involved a solution treatment and a double aging treatment of the deposited H13 tool steel prepared by *** aim is to optimize the microstructure and mechanical properties of SLMed H13 *** to the rapid heating and cooling effects of SLM,carbide precipitation in the deposited H13 steel was not uniform and residual stresses were *** purpose of the solution treatment is to dissolve the solution at a high temperature to eliminate the residual stresses and defects introduced by the SLM-forming *** solution treatment and first aging treatment produced the precipitation of small carbides at the grain boundaries and inside the crystals,which increased the hardness of SLMed H13 *** hardness increased from 538±4.0 HV of the as-deposited sample to 548±5.8 HV of samples after the first aging ***,the ultimate tensile strength and the elongation at break decreased from 1882 MPa and 11.5%in the as-deposited sample to 1697 MPa and 7.9%in those after the first aging treatment,***,the friction coefficient and wear rate in the as-deposited sample decreased from 0.5160 and 2.36×10^(–6)mm^(−3)N^(−1)m^(−1)to 0.4244 and 1.04×10^(–6)mm^(−3)N^(−1)m^(−1),***,the distribution of carbides inside the crystals was not *** second aging treatment adjusted the morphology of carbide precipitation and made it more uniform,but the precipitation of carbides grew and settled at the bottom of the grain *** hardness decreased to 533±6.7 HV compared with that with the first aging treatment,but the ultimate tensile strength and plasticity reached a balance(1807 MPa,14.05%).Accordingly,the friction coefficient and wear rate also showed a stable and decreasin

关键词： Selective laser melting H13 steel Solution aging Double aging Friction and wear Retained austenite