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Shape blending of artistic brushstroke represented by disk B-spline curves

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Progress in Natural Science:Materials International 2007年第12期17卷 1501-1507页

作者： Cheng Min1,2 and Wang Guojin1(1. Department of Mathematics, zhejiang university, hangzhou 310027, china 2. Department of Mathematics, zhejiang university of Technology, hangzhou 310032, china) Department of Mathematics Zhejiang University Hangzhou 310027 China 2. Department of Mathematics Zhejiang University of Technology Hangzhou 310032 China

This paper presents an algorithm for automatically generating in-between frames of two artistic brushstrokes. The basic idea of the algorithm is to represent the two key frames of artistic brushstrokes in disk B-spline curves, and then make blending of their geometric intrinsic variables. Given two key frames of artistic brushstrokes, the skeleton curves can be obtained by certain skeleton-based techniques. After disk B-spline representation of the key frames is generated, interpolation of the intrinsic variables of the initial and the target disk B-spline curves is carried out. Examples show that this method can efficiently create in-between frames of artistic brushstrokes.

关键词： computer aided calligraphy shape blending brushstroke disk B-spline curve skeleton.

STOCHASTIC MODELLING OF FATIGUE CRACK GROWTH UNDER CONSTANT AMPLITUDE LOADING

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Acta Mechanica Solida Sinica 1996年第2期9卷 169-178页

作者： Jiang Mingxiao Zhu Weiqiu, zhejiang university, hangzhou 310027, P. R. china zhejiang UNIV HANGZHOU 310027PEOPLES R CHINA

Two stochastic models of fatigue crack growth under constant amplitude cyclic loading are proposed and studied by using the stochastic averaging method and total probability theorem to account for high frequency component and low frequency component, respectively, of the irregular nature of fatigue crack growth observed in Virkler's experiment. Particular attention is paid to the prediction performance of the models under a change in the initial crack length. It is shown that the models proposed in the present paper yields better agreement with experimental data than other models available in literature.

关键词： stochastic averaging random fatigue crack growth fatigue crack growth cycles

Expression and Identification of Mutated Osteoprotegerin in Culture Cells and Larvae of Silkworm

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Acta Biochimica et Biophysica Sinica 2004年第5期36卷 331-335页

作者： Hai-Long XIAO, Yong-Feng JIN, and Yao-Zhou ZHANG1* Institute of Biochemistry, College of Life sciences, zhejiang university, hangzhou 310029, china College of Life sciences, zhejiang university of Science & Technology, hangzhou 310018, china College of Life sciences Zhejiang University of Science & TechnologyHangzhou 310018China Institute of Biochemistry College of Life SciencesZhejiang UniversityHangzhou 310029China

The mutated osteoprotegerin (OPG-372) gene was inserted into the baculovirus transfer vector pBacPAK8, and the recombinant plasmid was co-transfected with linearized Bm-BacPAK6 virus DNA into BmN cells, then homologous recombination occurred inside the cells. The recombinant virus BmNPV-OPG- 372 was screened and identified by Southern blotting. The recombinant human OPG-372 was expressed in cultured cells and the larvae of silkworm by inoculation of recombinant virus. The expression products were run on the SDS-PAGE and their immunoreactivities were determined by Western blotting. It was found that a 42 kD recombinant protein was expressed in BmN cells and a 46 kD one in larvae respectively. The bioactivi- ties of the recombinant proteins were determined by hypocalcemic effect assay in the mice. The results showed that the recombinant proteins had a significant hypocalcemic effect on mice sera.

关键词： OPG-372 silkworm baculovirus expression system hypocalcemic effect

Feedback minimization of first-passage failure of quasi integrable Hamiltonian systems

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Acta Mechanica Sinica 2007年第4期23卷 437-444页

作者： Maolin Deng Weiqiu Zhu Department of Mechanics,State Key Laboratory of Fluid Power Transmission and Control,zhejiang university,hangzhou 310027,china Department of Mechanics State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

Abstract A nonlinear stochastic optimal control strategy for minimizing the first-passage failure of quasi integrable Hamiltonian systems （multi-degree-of-freedom integrable Hamiltonian systems subject to light dampings and weakly random excitations） is proposed. The equations of motion for a controlled quasi integrable Hamiltonian system are reduced to a set of averaged It6 stochastic differential equations by using the stochastic averaging method. Then, the dynamical programming equations and their associated boundary and final time conditions for the control problems of maximization of reliability and mean first-passage time are formulated. The optimal control law is derived from the dynamical programming equations and the control constraints. The final dynamical programming equations for these control problems are determined and their relationships to the backward Kolmogorov equation governing the conditional reliability function and the Pontryagin equation governing the mean first-passage time are separately established. The conditional reliability function and the mean first-passage time of the controlled system are obtained by solving the final dynamical programming equations or their equivalent Kolmogorov and Pontryagin equations. An example is presented to illustrate the application and effectiveness of the proposed control strategy.

关键词： Nonlinear stochastic system First-passage time Reliability Stochastic control Dynamical programming

STUDY ON THE MORPHOLOGY OF POLYVINYL CHLORIDE/POLYSTYRENE BLENDS BY ELECTRON MICROPROBE ANALYSIS

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Chinese Journal of Polymer Science 2000年第5期18卷 437-441页

作者： Zheng-ping Fang Gen-lin Wang Guo-ping Cai Cheng-wei Xu Jie Qian Institute of Polymer Composites, zhejiang university, hangzhou 310027, china College of Chemical Engineering, zhejiang university of Technology, hangzhou 310014, china zhejiang Univ Inst Polymer Composites Hangzhou 310027 Peoples R China zhejiang Univ Technol Coll Chem Engn Hangzhou 310014 Peoples R China

The morphology of polyvinyl chloride/polystyrene (PVC/PS) blend samples with different mass ratios, prepared by means of solution casting and melt mixing, have been successfully examined by electron microprobe analysis (EMP). This experiment was performed in a scanning electron microscope attached to an energy dispersive X-ray analyzer. Differential scanning calorimetry was also used to investigate the phase separation of the blends. The results show that PVC and PS are incompatible and the blends have sea-islands phase structures. Blends prepared via melt mixing have finer phase-dispersion than those prepared via solution casting.

关键词： electron microprobe analysis polyvinyl chloride/polystyrene blends morphology

The structure of uniform B-spline curves with parameters

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Progress in Natural Science:Materials International 2008年第3期18卷 303-308页

作者： Juan Cao , Guozhao Wang Institute of Image Processing and Computer Graphic, Department of Mathematics, zhejiang university, hangzhou 310027, china Institute of Image Processing and Computer Graphic Department of Mathematics Zhejiang University Hangzhou 310027 China

The shape-adjustable curve constructed by uniform B-spline basis function with parameter is an extension of uniform B-spline curve. In this paper, we study the relation between the uniform B-spline basis functions with parameter and the B-spline basis functions. Based on the degree elevation of B-spline, we extend the uniform B-spline basis functions with parameter to ones with multiple parameters. Examples show that the proposed basis functions provide more flexibility for curve design.

关键词： Uniform B-spline Shape parameter Shape-adjustable curve Degree elevation

Technological paradigm and innovation of EST of SMEs in china

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Journal of Environmental sciences 1997年第1期9卷 120-126页

作者： Lu Yan Cai Ning School of Management,zhejiang university,hangzhou 310027,china School of Management Zhejiang University Hangzhou 310027 China

This article described the change of technological paradigm from environmentally un- friendly technology to environmentally sound technology(EST),and reported results from the in- vestigation made in 1993-1995 of how china's small-medium enterprises(SMEs)have been inno- vating technology in response to environmental pressures and tried to identify factors affecting china' SMEs to innovate more environmentally sound products and processes.

关键词： EST technology management SMEs.

GRAFTING OF HYDROPHILIC MONOMERS ONTO POLYURETHANE MEMBRANES BY SOLUTION OR PRE-ABSORBING METHODS FOR ACCELERATION OF CELL COMPATIBILITY

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Chinese Journal of Polymer Science 2001年第5期19卷 493-498页

作者： Chang-you Gao Jian-jun Guan Jia-cong Shen Department of Polymer Science and Engineering zhejiang university hangzhou 310027, china zhejiang Univ Dept Polymer Sci & Engn Hangzhou 310027 Peoples R China

Two grafting methods, i.e. solution grafting and pre-adsorbing, are introduced to covalently immobilizehydrophilic polymers on segmented polyurethane (SPU) to modify its hydrophilicity and to improve its cell *** grafting results in higher degree of grafting and rougher surface morphology. Cell culture evaluation demonstratesthat the modified membranes thus obtained are disadvantageous to the endothelial cell (ECs) growth probably because thehydrophilic groups on the surface are over-crowded. However, pre-absorbing grafting generates lower degree of grafting,which is detected and confirmed by ATR-FTIR spectra and water conted angle. Scanning electron microscopic (SEM)measurement shows that the latter method produces a plane and smooth morphology, which is similar to the SPU controlsample controlled. When grafting with lower monomer concentration, ECs could grow on SPU-g-PHEA [poly(2-hydroxyethyl acrylate)], SPU-g-PAAm (polyacrylamide), SPU-g-PDMA [poly(2-(dimethylamino)ethyl methacrylate)] orquatemized SPU-g-PDMA surface with elongated cell shapes. Hence, the cell compatibility of SPU is improved and a usefulmethod to construct a cell compatible layer on the polymer surface has been developed.

关键词： segmented polyurethane cell compatibility surface grafting endothelial cell

Geochemical migration of arsenic and its environmental efect

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Journal of Environmental sciences 1997年第2期9卷 37-46页

作者： Weng Huanxin, Lan Xiang Department of Earth sciences, zhejiang university, hangzhou 310027, china

This paper presents the results of a field study regarding the transport and environmental fate of arsenic. Concentrations of arsenic and various forms of its compounds in rock, soil, river water, and river bottom deposits in an area near hangzhou, china, were measured and analyzed. On the basis of these field data, the source and interface transfer of arsenic were discussed. A few very interesting findings were reported. This paper indicates that there was relatively low arsenic concentration in Jing Hang Canal, whereas, rather high arsenic concentration in the river bottom mud was found. The paper attributed this phenomenon to mechanism of arsenic deposition and absorption in the water column, the canal has a rather high self purification ability relative to the arsenic input.

关键词： arsenic geochemical migration environmental effect.