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Short cycle structures for graphs on surfaces and an open problem of Mohar and Thomassen

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science china Mathematics 2006年第2期49卷 212-224页

作者： REN Han & DENG Mo department of Mathematics, east china {3. university, shanghai 200062, china College of Mathematics & information science, Northwest {3. university, Lanzhou 73.070, china 1. department of Mathematics East China Normal University Shanghai 200062 China 2. College of Mathematics & information science Northwest Normal University Lanzhou 730070 China

In this paper we investigate cycle base structures of a (weighted) graph and show that much information of short cycles is contained in an MCB (i.e., minimum cycle base). After setting up a Hall type theorem for base-transformation, we give a sufficient and necessary condition for a cycle base to be an MCB. Furthermore, we show that the structure of MCB in a (weighted)graph is unique. The property is also true for those having a longest length (although much work has been down in evaluating MCB, little is known for those having a longest length). We use those methods to find out some unknown properties for short cycles sharing particular properties in (unweighted) graphs. As applications, we determine the structures of short cycles in an embedded graph and show that there exist polynomially bounded algorithms in finding a shortest contractible cycle and a shortest two-sided cycle provided such cycles exist. Those answer an open problem of B. Mohar and C. Thomassen.

关键词： cycle base facial cycle graph embedding.

An improved approach to the efficient construction of and search operations in motion graphs

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science china(information sciences) 2012年第5期55卷 1042-1051页

作者： GAO Yan 1,CHEN ZhiHua 2,CHEN MinGang 3.& SHEN Yang 3.1 Software Engineering Institute,east china normal {3.sity,shanghai 200062,china 2 department of Computer science and Engineering,east china {3.sity of science and technology,shanghai 20023.,china 3.department of Computer science and Engineering,shanghai Jiao Tong {3.sity,shanghai 200240,china 1. Software Engineering Institute East China Normal University Shanghai 200062 China2. Department of Computer Science and Engineering East China University of Science and Technology Shanghai 200237 China3. Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China

Motion graphs have been widely used as an effective technique in the synthesis of human *** synthesize well-formed motions,motion graphs require smooth transitions and good ***,the time and costs grow quadratically as the graph size *** this paper,we present a method to set up a hierarchical structure,called a structure *** coarse level of this graph models different motion categories and their transitions,and the fine level mainly captures different motion *** interpolation space method is used to improve the graph connectivity at the fine *** structure guides the establishment of a faster and more realistic graphical *** the building process,this structure also helps with searching the motion graph,by performing a traverse search and placing the findings into a direct look-up table or local search ***,when there is no direct link between the different motions,a navigation map is introduced to conduct an appropriate search path via a series of transition motion *** experimental results indicate that our approach could lower the computation time in construction and searching,while simultaneously providing a richer variety of motion styles.

关键词： motion graph structure table registration curve motion interpolation

Denitrification in Chongming east tidal flat sediment, Yangtze estuary, china

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science china Earth sciences 2006年第10期49卷 1090-1097页

作者： WANG Dongqi1,2, CHEN Zhenlou1,3. XU Shiyuan1,2, HU Lingzhen1 & WANG Jun1,2 1. College of Resources & Environment, east china normal {3.sity, shanghai 200062, china 2. State Key Laboratory of Estuarine and Coastal Sediment Dynamics and Morphodynamics, east china normal {3.sity, shanghai 200062, china 3. Key Laboratory of Geographical information science of Ministry of Education,east china normal {3.sity,shanghai 200062, china 1. College of Resources & Environment East China Normal University Shanghai 200062 China 2. State Key Laboratory of Estuarine and Coastal Sediment Dynamics and Morphodynamics East China Normal University Shanghai 200062 China 3. Key Laboratory of Geographical information science of Ministry of Education East China Normal University Shanghai 200062 China

From July 2003.to July 2004, samples were collected on Chongming Island east tidal flat every two months. The research showed that the nitrous oxide (N2O) production rate was very low in the water, Chongming east tidal flat (CM) sediment was the N2O source of the water. Sediment N2O natural production rate was between -0.08 and 1.74 μmolN·m-2·h-1. N2O natural production rate was higher in the summer. The difference of the N2O natural production rate in the different tidal flats, the correlation between the N2O natural production rate and the denitrification rate, and those with the temperature and DO indicate that middle tidal flat sediment denitrification was the main process of the N2O production, while in the low tidal flat sediment, the production of the N2O came from several processes of the nitrogen cycling. Tidal flat sediment denitrification reaction was stronger in summer and winter but relatively lower in the late autumn and early spring. Seasonal change of the sediment denitrification rate was wide, from 1.12 to 3..3. μmolN·m-2·h-1. Temperature, DO and the coactions of them had the prominent effect on the tidal flat sediment denitrification.

关键词： Yangtze estuary, tidal flat sediment, denitrification, nitrous oxide, effect factor.

Enhancing Positive Citizenship Ideals on Students Through Bibliotherapy and Cognitive Counseling

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心理科学 2002年第1期25卷 47-52页

作者： Ismail Hussein Hashim (east china normal {3.sity department of Psychology,shanghai,200062) eastchinanormal{3.sitydepartmentofPsychology Shanghai200062

The paper views feelings touching as very important in cultivating positive citizenship ideals amongst the *** main preoccupation of the study was to provide relevant information concerning the efficacy of bibliotherapy and cognitive counseling as two methods that could be applied by counselors in school field to promote positive citizenship ideals in the *** study was carried out in Alfashir principality (Sudan)in April *** of one hundred and twenty five secondary school students were touched with regards to what they regarded as citizenship *** control and experimental measures approach,the two groups of the subjects were treated to bibliotherapy and cognitive counseling, while the third group was left as control *** indicated significant differences in the efficacy of the two methods for positively fostering citizenship ideals among the youth in favor of *** results have demonstrated that bibliotherapy can be effectively applied in school setting through the school curriculum to positively foster citizenship ideals among the youth.

关键词：学生心理学读书疗法认知咨询服务心理研究教育心理学

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 {3.sity,shanghai 200240,china 2 Academy of information technology,Luoyang normal {3.sity,Luoyang 471022,china 3.department of Computer science and Engineering,east china {3.sity of science and technology,shanghai 20023.,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

A computational investigation of boron-doped chromium and chromium clusters by density functional theory

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science china(Physics,Mechanics & Astronomy) 2010年第5期53卷 812-817页

作者： GE GuiXian1,JING Qun1 & LUO YouHua2,3.1 Key Laboratory of Ecophysics and department of Physics,normal College,Shihezi univer{3.,Xinjiang 83.003.china 2 school of science,east china univer{3. of science and technology,{13. 20023.,china 3.Institute of Theoretical Physics,school of Physics and information Optoelectronics,Henan univer{3.,Kaifeng 475004,china 1. Key Laboratory of Ecophysics and department of Physics Normal College Shihezi University Xinjiang 832003 China2. School of Science East China University of Science and Technology Shanghai 200237 China3. Institute of Theoretical Physics School of Physics and Information Optoelectronics Henan University Kaifeng 475004 China

The geometries,stabilities and electronic properties of Crn and CrnB(n=2-9) clusters have been systematically investigated by density functional *** results suggest that the lowest energy structures for CrnB clusters can be obtained by substituting one Cr atom in Crn+1 clusters with B *** geometries of CrnB clusters are similar to that of Crn+1 clusters except for local structural *** second-order difference and fragmentation energy show Cr4,Cr6,Cr8,Cr3.,Cr5B and Cr8B cluster are the most stable among these studied *** impurity B increases the stabilities of chromium *** B is doped on the Crn clusters,cluster geometry does dominate positive role in enhancing their *** doped B atom does not change the coupling way of the Cr site in Crn clusters,but breaks the symmetry and the Cr atoms are no longer *** doped B atom increases the total magnetic moments of Crn in most cases.

关键词： Crn and CrnB clusters geometries electronic properties

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 {3.sity,shanghai 200240,china 2 Software Engineering Institute,east china normal {3.sity,shanghai {13.,china 1. department of Computer science and Engineering Shanghai Jiao Tong University Shanghai 200240 China2. Software Engineering Institute East China Normal University Shanghai 200062 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

CURVILINEAR PATHS AND TRUST REGION METHODS WITH NONMONOTONIC BACK TRACKING TECHNIQUE FOR UNCONSTRAINED OPTIMIZATION

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Journal of Computational Mathematics 2001年第3期19卷 241-258页

作者： De-tong Zhu (department of Mathematics, shanghai normal {3.sity, shanghai 20023., china) 上海师范大学上海 200234

Focuses on a study which examined the modification of type approximate trust region methods via two curvilinear paths for unconstrained optimization. Properties of the curvilinear paths; Description of a method which combines line search technique with an approximate trust region algorithm; information on the convergence analysis; Details on the numerical experiments.

关键词： curvilinear paths trust region methods nonmonotonic technique unconstrained optimization

GENERAL CAUCHY PROBLEM FOR THE LINEAR SHALLOW-WATER EQUATIONS ON AN EQUATORIAL BETA-PLANE

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Journal of Hydrodynamics 2006年第3期18卷 303-309页

作者： SHEN Chun SHI Wei-hui school of Mathematics and information Yantai Normal University Yantai 264025 China shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China department of Mathematics Shanghai University Shanghai 200444 China

Based on the theory of stratification, the well-posedness of the initial value problem for the linear shallow-water equations on an equatorial beta-plane was discussed. The sufficient and necessary conditions of the existence and uniqueness for the local solution of the equations were presented and the existence conditions for formal solutions of the equations vere also given. For the Cauchy problem on the hyper-plane {t = O}, the local analytic solution were worked out and a special case was discussed. Finally, an example was used to explain the variety of formal solutions for the ill-posed problem.

关键词： stratification initial value problem,well-posedness shallow-water equations