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Synthesis and crystal structure of complex of Ce(NO_3)_3 with N-(3-methyl-pyridin-2-yl)-formimidoyl-(3-methyl-pyridin-2-yl) hydrazone

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science china Chemistry 2004年第3期47卷 251-256页

作者： JIANG Yinzhi1,2 & HU Weixiao1 1. department of Pharmaceutical science, zhejiang university of technology, hangzhou 310032, china 2. department of Applied Chemistry, zhejiang Institute of science and technology, hangzhou 310033, china 1. department of Pharmaceutical science Zhejiang University of Technology 310032 Hangzhou China 2. department of Applied Chemistry Zhejiang Institute of Science and Technology 310033 Hangzhou China

The reaction of 3,6-di-(3-methyl-pyridin-2-yI)-s-tetrazine (DMPTZ, II) with CeIII salt [Ce(NO3)3 · 6H2O] generates a new ligand, N-(3-methyl-pyridin-2-yl)-formimidoyl-(3-methyl-pyridin-2-yl) hydrazone (L), and forms a new complex: a mononuclear complex [Ce(L)(NO3)2 (H2O)3] · NO3 (III). Crystal data for III: space group P-1, with a = 0.7133(4) nm, b = 1.1139(2) nm, c = 1.4572(3) nm, α= 102.13(2)°, β= 99.81(3)°, γ= 91.10(3)°, Z = 2, V = 1113.6(7) nm3, μ = 2.123 mm?1 and F(000) = 630. L acts as a tri-dentate chelating ligand in III. There are 10 coordination sites around Ce3+ of III, which are respectively occupied by seven oxygen atoms (four from two nitrate anions and three from three H2O molecules) and three nitrogen atoms (all from L). The cerium atom and three chelating nitrogen atoms are coplanar. The mechanism of the metal assisted decomposition is discussed briefly.

关键词： rare earth, complex, crystal structure, synthesize, 3,6-bis (3-methyl-pyridin-2-yl)-s-tetrazine, N-(3-methyl-pyridin- 2-yl)-formimidoyl-(3-methyl-pyridin-2-yl) hydrazone.

Generative computer simulation for parallel layout of multi-story row house cluster

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science china(Technological sciences) 2010年第7期53卷 1785-1791页

作者： DING XiYing1,2 1 Zhenjianguniversity, hangzhou 310058, china 2 zhejiang university of science & technology, hangzhou 310058, china 1. Zhenjiang university Hangzhou 310058 China2. Zhejiang University of Science & Technology Hangzhou 310058 China

This study has established the functions between the environmental conditions and the inhabitants’ preferences for multi-story row house cluster with parallel layout, based on the data from the questionnaires’ in Beijing. A program has been written with multi-agent system and generative computer simulation approaches. The emergence candidate layout plans can be referenced and chosen by architects.

关键词： multi-agent system bottom up generative computer simulation multistory row house cluster parallel layout

Clustering-based hyperspectral band selection using sparse nonnegative matrix factorization

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Journal of zhejiang university-science C(computers and Electronics) 2011年第7期12卷 542-549页

作者： Ji-ming LI 1,2,Yun-tao QIAN 1 (1 School of computer science and technology,zhejiang university,hangzhou 310027,china) (2 zhejiang Police College,hangzhou 310053,china) School of computer science and technology Zhejiang University zhejiang Police College

Hyperspectral imagery generally contains a very large amount of data due to hundreds of spectral *** selection is often applied firstly to reduce computational cost and facilitate subsequent tasks such as land-cover classification and higher level image *** this paper,we propose a new band selection algorithm using sparse nonnegative matrix factorization (sparse NMF).Though acting as a clustering method for band selection,sparse NMF need not consider the distance metric between different spectral bands,which is often the key step for most common clustering-based band selection *** imposing sparsity on the coefficient matrix,the bands' clustering assignments can be easily indicated through the largest entry in each column of the *** results showed that sparse NMF provides considerable insight into the clustering-based band selection problem and the selected bands are good for land-cover classification.

关键词： Hyperspectral Band selection Clustering Sparse nonnegative matrix factorization

A general communication performance evaluation model based on routing path decomposition

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Journal of zhejiang university-science C(computers and Electronics) 2011年第7期12卷 561-573页

作者： Ai-lian CHENG 1,Yun PAN 1,2,Xiao-lang YAN 2,Ruo-hong HUAN 3 (1 department of Information science and Electronic Engineering,zhejiang university,hangzhou 310027,china) (2 Institute of VLSI Design,zhejiang university,hangzhou 310027,china) (3 College of computer science and technology,zhejiang university of technology,hangzhou 310023,china) department of Information science and Electronic Engineering Zhejiang University Institute of VLSI Design Zhejiang University

The network-on-chip (NoC) architecture is a main factor affecting the system performance of complicated multi-processor systems-on-chips (MPSoCs).To evaluate the effects of the NoC architectures on communication efficiency,several kinds of techniques have been developed,including various simulators and analytical *** simulators are accurate but time consuming,especially in large space explorations of diverse network configurations;in contrast,the analytical models are fast and flexible,providing alternative methods for performance *** this paper,we propose a general analytical model to esti-mate the communication performance for arbitrary NoCs with wormhole routing and virtual channel flow *** resolve the inherent dependency of successive links occupied by one packet in wormhole routing,we propose the routing path decomposition approach to generating a series of ordered link *** we use the traditional queuing system to derive the fine-grained transmission latency for each network *** to our experiments,the proposed analytical model provides a good approximation of the average packet latency to the simulation results,and estimates the network throughput precisely under various NoC configurations and ***,the analytical model runs about 10 5 times faster than the cycle-accurate NoC *** applications of the model including bottleneck detection and virtual channel allocation are also presented.

关键词： Analytical model Communication performance Network-on-chip (NoC) Queuing system Routing path decom-position Virtual channel

Approximate merging of multiple Bézier segments

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Progress in Natural science:Materials International 2008年第6期18卷 757-762页

作者： Min Chenga,b,Guojin Wanga,* aInstitute of computer Graphics and Image Processing,zhejiang university,hangzhou 310027,china bCollege of science,zhejiang university of technology,hangzhou 310032,china Institute of computer Graphics and Image Processing Zhejiang University Hangzhou 310027 China College of science Zhejiang University of Technology Hangzhou 310032 China

This paper deals with the approximate merging problem of multiple adjacent Bézier curves with dierent degrees by a single Bézier curve,which is a frequently seen problem in *** unified matrix representation for precise merging is presented and the approx-imate merging curve is further derived based on matrix *** at the endpoints of curves is also discussed in the merging *** show that the method in this paper achieves satisfying merging results.

关键词： computer-aided geometric design Bézier curve Approximate merging Matrix representation

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.

Group sparse representation for image categorization and semantic video retrieval

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science china(Information sciences) 2011年第10期54卷 2051-2063页

作者： LIU YaNan 1,2 ,WU Fei 2 & ZHUANG YueTing 2 1 School of Information,zhejiang university of Finance & Economics,hangzhou,310018,china 2 College of computer science and technology,zhejiang university,hangzhou,310012,china 1. School of Information Zhejiang University of Finance & Economics Hangzhou 310018 China2. College of Computer Science and Technology Zhejiang University Hangzhou 310012 China

Multimedia content analysis and management are a promising and challenging *** this paper we develop a novel approach to image representation,which we call group sparse representation (GSR),for image classification and video *** basic idea is to represent a test image as a weighted combination of all the training *** particular,we introduce two sets of weight coefficients,one for each training image and the other for each ***,we formulate our concern as a group nonnegative garrote *** resulting representations are sparse,and they are appropriate for discriminant *** on Caltech101 and PASCAL VOC2008 image dataset and TRECVID2005 video corpus testify that our proposed approach is efficient and effective.

关键词： compressive sensing group sparse representation bag-of-SIFT-words nonnegative garrote l1-minimization apcluster

Dynamic behavior of polymer surface and the time dependence of contact angle

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science china Chemistry 2005年第6期48卷 553-559页

作者： WANG Xinping1, CHEN Zhifang1 & SHEN Zhiquan2 1. Key Laboratory of Advanced Textile Materials and Manufacturing technology of Education Ministry, department of Applied Chemistry, zhejiang Institute of science and technology, hangzhou 310033, china 2. department of Polymer science and Engineering, zhejiang university, hangzhou 310027, china 1. department of Applied Chemistry Zhejiang Institute of Science and Technology Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Education Ministry 310033 Hangzhou China 2. department of Polymer science and Engineering Zhejiang University 310027 Hangzhou China

Time-dependent contact angles were measured by depositing sessile drops of wa-ter on the polymer surfaces and monitoring the drop shape as a function of time. It was found that contact angles decreased sharply with contact time and the equilibrium contact angle was finally attained after a certain time. Values of starting (θ s) and equilibrium contact angles (θ e) obtained by the sessile drop method depend on polymer properties. The Wilhelmy plate technique was used to measure advancing and receding contact angles. The variations of starting (θ s) and equilibrium contact angles (θ e), advancing (θ a) and receding contact angles (θ r) have been studied on the oxidized surface of polymers containing polybutadiene block to explore the cause of time-dependence in contact angle measurement and the meaning of θ s and θ e. The results showed the linear relationships between starting (θ s) and advancing contact angles (θ a), the equilibrium (θ e) and receding contact angles (θ r). The similar relationship was also established between the contact angle hysteresis (θ a?θ r) and differences (θ s ?θ e) in starting contact angles and equilibrium contact angles. Therefore, time-dependence in contact angle measurement was mainly attributed to the surface reconstruction when water drops were deposited on polymer surfaces. The starting contact angle was contributed by the hydrophobic component on polymer surface and the equilibrium contact angle mainly by the hydrophilic component of polymer. These results not only demonstrated the interdependency between two contact angle measurements, the sessile drop method and the Wilhelmy plate technique, but also provided the experimental evidence to explain the cause of time-dependent contact angle. This may also provide a new method to study dynamic behavior of polymer surface.

关键词： contact angle, surface dynamic behavior, polymer surface, dynamic contact angle, time-dependence.

Interactive point cloud blending by drag-and-drop

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Journal of zhejiang university-science A(Applied Physics & Engineering) 2007年第10期8卷 1633-1641页

作者： ZOU Wan-hong?1, DING Zhan1, YE Xiu-zi1, CHEN Zhi-yang2 (1State Key Lab. of CAD and CG, School of computer science and technology, zhejiang university, hangzhou 310027, china) (2Software College, zhejiang university of technology, hangzhou 310014, china) State Key Lab. of CAD CG School of Computer Science technology Zhejiang University Hangzhou 310027 China Software College Zhejiang University of Technology Hangzhou 310014 China

With the rapid development of 3D digital photography and 3D digital scanning devices, massive amount of point samples can be generated in acquisition of complex, real-world objects, and thus create an urgent need for advanced point-based processing and editing. In this paper, we present an interactive method for blending point-based geometries by dragging-and- dropping one point-based model onto another model’s surface metaphor. We first calculate a blending region based on the polygon of interest when the user drags-and-drops the model. Radial basis function is used to construct an implicit surface which smoothly interpolates with the transition regions. Continuing the drag-and-drop operation will make the system recalculate the blending regions and reconstruct the transition regions. The drag-and-drop operation can be compound in a constructive solid geometry (CSG) manner to interactively construct a complex point-based model from multiple simple ones. Experimental results showed that our method generates good quality transition regions between two raw point clouds and can effectively reduce the rate of overlapping during the blending.

关键词： Drag-and-drop Point cloud model Interactive blending Geometry modeling