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Seamlet carving for shape-aware image resizing

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Science china(Information Sciences) 2012年第5期55卷 1073-1081页

作者： LIN Xiao 1,2,SHENG Bin 1,MA LiZhuang 1,SHEN Yang 1 & CHEN ZhiHua 3 1 department of Computer Science and engineering,Shanghai Jiao Tong university,Shanghai 200240,china 2 Academy of Information Technology,Luoyang Normal university,Luoyang 471022,china 3.department of Computer Science and engineering,East china university of Science and Technology,Shanghai 200237,china 1. department of Computer Science and engineering Shanghai Jiao Tong University Shanghai 200240 China2. Academy of Information Technology Luoyang Normal University Luoyang 471022 China3. Department of Computer Science and Engineering East China University of Science and Technology Shanghai 200237 China

In this paper we propose an optimized seam-carving approach for anti-shearing image *** image/video seam-carving strategy only focuses on deleting the pixels along 8-connected seams,which may lead to the obvious information loss during *** the traditional seam-carving methods,our approach can construct a seamlet to handle the discontinuous pixels and further achieve an optimized image resizing results with *** particular,to suppress zigzag artifacts,we introduce the anti-shearing energy into the seamlet generation,which includes two steps:1) the energy map is formalized by using Gabor filtering and the saliency map;2) The energy computation is optimized in Gabor feature space to obtain the resizing results without the connectivity *** experimental results and comparisons show the effectiveness of our method.

关键词： image resizing seamlet carving saliency map

Overall Planning of Development of Urban-Rural Areas:A Policy Mechanism for Urban-Rural Coordinated Growth

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Chinese Journal of Population,Resources and Environment 2004年第1期2卷 57-60页

作者： Sun JinSociology department, china agricultural university, Beijing 100874, china Sociology department China Agricultural University Beijing 100874 China

While analyzing overall planning and coordinated development of urban-rural areas, this paper shows that overall planning for the development of urban-rural areas is a requirement for the best use of productive forces. It means the setting up of a policy mechanism for coordinated growth. Recognizing this, the government should set up a way to lead and manage a unified program to increase service and decrease controlling administration power, while safeguarding and fulfilling the farmers' ownership to the means of production.

关键词： Overall planning of development of urban-rural areas Cxjordinated development of urban-rural areas

Mathematic Expression of Kinetic Compensation Effect and Relationship between the Exothermic Decomposition Temperature and Critical Temperature of Thermal Explosion of Eighty-six Energetic Materials

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含能材料 2001年第1期9卷 8-9页

作者： HU Rong zu 1, YANG De suo 2, ZHANG Jiao qiang 3 (1. department of Chemistry,Northwest university, Xi′an 710065, china 2. department of Chemistry and Chemical engineering, Baoji College of Arts and Science, Baoji 721007, china 3. department of 西北大学陕西西安 710065 宝鸡文理学院陕西 721007 西北工业大学陕西西安 710072

Two relationships are established using the least squares method,between the kinetic parameters (the apparent activation energy and pre exponential constant),and the exothermic decomposition temperature and ther... 详细信息

关键词： critical temperature of thermal explosion decomposition temperature DSC energetic materials.

Thermoelastic properties of sandwich materials with pin-reinforced foam cores

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Science china(Technological Sciences) 2008年第12期51卷 2059-2074页

作者： LU TianJian1,LIU Tao2,3 & DENG ZiChen2,4 1 MOE Key Laboratory of Strength and Vibration,School of Aerospace,Xi’an Jiaotong university,Xi’an 710049,china 2 department of engineering Mechanics,Northwestern Polytechnical university,Xi’an 710072,china 3.department of engineering,university of Cambridge,Cambridge CB2 1PZ,UK 4 State Key Laboratory of Structural Analysis of Industrial Equipment,Dalian university of Technology,Dalian 116024,china MOE Key Laboratory of Strength and Vibration School of Aerospace Xi’an Jiaotong University Xi’an 710049 China department of engineering Mechanics Northwestern Polytechnical University Xi’an 710072 China department of engineering University of Cambridge Cambridge CB2 1PZ UK State Key Laboratory of Structural Analysis of Industrial Equipment Dalian University of Technology Dalian 116024 China

Pin-reinforced foam is a novel type of sandwich core materials formed by inserting pins(trusses) into a foam matrix to create a truss-like network reinforced foam *** loading,the pins deform predominantly by local stretching whilst the deformation of foam is governed by local *** paper presents a theoretical study on the thermoelasticity of pin-reinforced foam sandwich *** calculate the effective thermoelastic properties of pin-reinforced foam cores,the energy-based homogenization approach is employed to develop a micromechanics-based model,calibrated by the existing experimental *** is found that the stiffness of the sandwich core is mainly governed by pin reinforcements:the foam matrix contributes little to sandwich *** with traditional foam cores without pin reinforcements,the changes in inplane thermal expansion coefficients are not vigorous as a result of pin reinforcements,while the through-thickness thermal expansion coefficient changes *** is also demonstrated that it is possible to design materials with zero or negative thermal expansion coefficients under such a context.

关键词： sandwich panel pin reinforcement analytical solutions homogenization thermoelasticity thermal expansion

New discrete element models for elastoplastic problems

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Acta Mechanica Sinica 2009年第5期25卷 629-637页

作者： Ming Cheng Weifu Liu Kaixin Liu LTCS and department of Mechanics and Aerospace engineering,College of engineering, Peking university, 100871 Beijing, china LTCS and department of Mechanics and Aerospace engineering College of Engineering Peking University 100871 Beijing China

The discrete element method （DEM） has attractive features for problems with severe damages, but lack of theoretical basis for continua behavior especially for nonlinear behavior has seriously restricted its application. The present study proposes a new approach to developing the DEM as a general and robust technique for modeling the elastoplastic behavior of solid materials. New types of connective links between elements are proposed, the interelement parameters are theoretically determined based on the principle of energy equivalence and a yield criterion and a flow rule for DEM are given for describing nonlinear behavior of materials. Moreover, a numerical scheme, which can be applied to modeling the behavior of a continuum as well as the transformation from a continuum to a discontinuum, is obtained by introducing a fracture criterion and a contact model into the DEM. The elastoplastic stress wave propagations and the tensile failure process of a steel plate are simulated, and the numerical results agree well with those obtained from the finite element method （FEM） and corresponding experiment, and thus the accuracy and efficiency of the DEM scheme are demonstrated.

关键词： DEM Continuum Plasticity Fracture

CO_2 Mitigation in Coal Gasification Cogeneration Systems with Integration of the Shift Reaction, CO_2 Absorption and Methanol Production

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Journal of Thermal Science 2004年第3期13卷 193-198页

作者： Yuanyuan DUAN Jin ZHANG Key Laboratory of Thermal Science and Power engineering, department of Thermal engineering, Tsinghua university, Beijing 100084, china Key Laboratory of Thermal Science and Power engineering Department of Thermal Engineering Tsinghua University Beijing China

Cogeneration of electricity and liquid fuel can achieve higher efficiencies than electricity generation alone in Integrated Gasification Combined Cycle (IGCC), and cogeneration systems are also expected to mitigate CO2 emissions. A proposed methanol-electricity cogeneration system was analyzed in this paper using exergy method to evaluate the specified system. A simple cogeneration scheme and a complicated scheme including the shift reaction and CO2 removal were compared. The results show that the complicated scheme consumes more energy, but has a higher methanol synthesis ratio with partial capture of *** those methanol and electricity cogeneration systems, the CO2 mitigation is not merely an additional process that consumes energy and reduces the overall efficiency, but is integrated into the methanol production.

关键词： cogeneration system methanol synthesis CO2 mitigation exergy analysis

Synthesis of N-acetamide C_(60) nitride and its performance of optical limiting

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Chinese Science Bulletin 2000年第2期45卷 150-153页

作者： TANG Guangshi, ZHU Hesun & SONG Yinglin Research Center of Materials Science, Beijing Institute of Technology, Beijing 100081, china department of Applied Physics, harbin Institute of Technology. harbin 150001. china department of Applied Chemiscy Beiji Research Center of Materials Science Beijing institute of Technology Beijing China department of Applied Chemistry Beijing University of Chemicals Technology Beijing China department of Applied Physics Harbin Institute of Technology Harbin China

N-acetamide C60 nitride (N-acetamide-1,2-dihydro-1,2-aza-fullerene[60]) has been synthesized by the reaction of C60 and azidoacetamide and initially characterized. Its mechanism was that the objective product is formed through intermediate triazoline. The computational study shows that N-nitride structure is thermodynamically more stable by using the semi-empirical AM1 SCF-MO method. The properties of optical limiting were tested by using double frequency Nd: YAG pulse laser system and showed that the optical limiting mechanism is reverse saturation absorption. At wavelength of 532 nm, compared with optical limiting for ns pulse, this new material has good optical limiting character for ps pulse. At wavelength of 707 nm. the capacity of optical limiting of the derivative is prior to C60-

关键词： C60 derivatives N-nitride structure optical limiting properties reverse saturation absorption.

SYNTHESIS AND CHARACTERIZATION OF FOUR-ARMED BLOCK POLY(STYRENE-b-p-NITROPHENYL METHACRYLATE)PREPARED BY THE ATRP METHOD

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Chinese Journal of Polymer Science 2002年第4期20卷 353-360页

作者： Cai-yuan Pan Lei Tao Ye Liu department of Polymer Science and engineering university of Science and Technology of china, Hefei 230026 china department of Polymer Science and engineering University of Science and Technology of China Hefei 230026

A novel tetrafunctional initiator, C [CH_2O (CH_2)_3 OOCCH(Br)CH_3]_4 (1), was synthesized through the reaction oftetraol with α-bromopropionyl chloride, and then was used as initiator of atom transfer radical polymerization (ATRP) in thepreparation of 4-armed polystyrene (PSt) with narrow polydispersity. The structure, molecular weight and molecular weightdistribution (MWD) of each arm were studied by ~1H-NMR and GPC data of hydrolyzed products of the 4-armed PSt. TheATRP of St using 1/CuBr/bpy as initiator system is of 'living' character based on the following evidence: narrow MWD,constant concentration of chain radical during the polymerization, control of molecular weight by the molar ratio of monomerconsumed to 1. The 4-armed poly(St-b-p-nitrophenyl methacrylate) [poly(St-b-NPMA)] was prepared by the ATRP ofNPMA using 4-armed PSt with terminal bromine as the initiator, and characterized by FT-IR, ~1H-NMR spectra and GPCcurves. The micelles with PSt as core, and PNPMA as shell were formed by dropping DMSO into a solution of 4-armedpoly(St-b-NPMA) in DMF, as proved by laser light scatter (LLS) method.

关键词： Tetrafunctional initiator Atom transfer radical polymerization 4-Armed polystyrene 4-Armed poly(styrene-b-pnitrophenyl methacrylate) Unimolecular micelles

SURFACE MODIFICATION OF CaCO_3 WITH DENDRITIC CARBOXYLIC ACIDS

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Chinese Journal of Polymer Science 2002年第3期20卷 231-235页

作者： Zhao-xia Guo Jian Yu Institute of Polymer Science and engineering department of Chemical engineering Tsinghua university Beijing 100084 china Tsing Hua Univ Dept Chem Engn Inst Polymer Sci & Engn Beijing 100084 Peoples R China

Nanometer calcium carbonate was modified with Frechet type polyether dendrons bearing a COOH group at thefocal point by a wet-coating technique in dichloromethane at room temperature. The interaction between CaCO;and thedendritic modifier was proven by IR and mass spectroscopy of the modified CaCO;after thorough extraction withdichloromethane. The amount of tightly bonded organic modifier was estimated by TGA. It was shown that the amount ofbonded molecules decreased with increasing generation number due to the larger number of branches. Compared tounmodified CaCO;, the modified CaCO;possess different dispersibility in water and in organic solvents.

关键词： calcium carbonate surface modification polyether dendrimer dendritic carboxylic acid