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Mixed boundary conditions for piezoelectric plates

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Science china(Physics,Mechanics & Astronomy) 2009年第5期52卷 755-761页

作者： GAO Yang 1 ,XU SiPeng 2 &ZHAO BaoSheng 3 1college of Science,china Agricultural University,Beijing 100083,china 2college of Engineering,Ocean University of china,Qingdao 266071,china 3 School of Mechanical Engineering,University of Science and Technology of Liaoning,Anshan 114044,china college of Science China Agricultural University Beijing 100083 China college of Engineering Ocean University of China Qingdao 266071 China School of Mechanical Engineering University of Science and Technology of Liaoning Anshan 114044 China

For plate bending and stretching problems in piezoelectric materials,the reciprocal theorem and the general solution of piezoelasticity are applied in a novel way to obtain the appropriate mixed boundary conditions accurate to all order.A decay analysis technique is used to establish necessary conditions that the prescribed data on the edge of the plate must satisfy in order that it should generate a decaying state within the *** the case of axisymmetric bending and stretching of a circular plate,these decaying state conditions are obtained explicitly for the first time when the mixed conditions are imposed on the plate *** are then used for the correct formulation of boundary conditions for the interior solution.

关键词： boundary conditions piezoelectric plates mixed data bending problems stretching problems

Maschke-type theorem and Morita context over weak Hopf algebras

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Science china Mathematics 2006年第5期49卷 587-598页

作者： ZHANG Liangyun college of Science, Nanjing Agricultural University, Nanjing 210095, china Department of Mathematics, Nanjing University, Nanjing 210008, china 1. college of Science Nanjing Agricultural University Nanjing 210095 China 2. Department of Mathematics Nanjing University Nanjing 210008 China

This paper gives a Maschke-type theorem over semisimple weak Hopf algebras,extends the well-known Maschke-type theorem given by Cohen and Fishman and constructs a Morita context over weak Hopf algebras.

关键词： weak Hopf algebra, smash product, Maschke-type theorem, Morita context.

Boundary conditions for the bending of a piezoelectric beam

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Science china(Physics,Mechanics & Astronomy) 2008年第7期51卷 847-856页

作者： GAO Yang1, XU SiPeng2 & ZHAO BaoSheng3 1 college of Science, china Agricultural University, Beijing 100083, china 2 college of Engineering, Ocean University of china, Qingdao 266071, china 3 School of Mechanical Engineering, University of Science and Technology Liaoning, Anshan 114044, china 1. college of Science China Agricultural University Beijing 100083 China 2. college of Engineering Ocean University of China Qingdao 266071 China 3. School of Mechanical Engineering University of Science and Technology Liaoning Anshan 114044 China

For beam bending in transversely isotropic piezoelectric media, the reciprocal theorem and the general solution of piezoelasticity are applied in a novel way to obtain the appropriate stress and mixed boundary conditions accurate to all orders for the beam of general edge geometry and loadings. By generalizing the method developed by Gregory and Wan, a set of necessary conditions on the edge-data for the existence of a rapidly decaying solution is established. The prescribed edge-data of the beam must satisfy these conditions in order that they could generate a decaying state within the beam. When stress and mixed conditions are imposed on the beam edge, these decaying state conditions for the case of bending deformation of piezoelectric beam are derived explicitly. They are then used for the correct formulation of boundary conditions for the beam theory solution (or the interior solution). Besides, an analytical solution of elastic beam is formulated to verify validity of our boundary conditions. For the stress data, our boundary conditions coincide with those obtained in conventional forms of beam theories. More importantly, the appropriate boundary conditions with two sets of mixed edge-data are obtained for the first time.

关键词： boundary conditions beam bending piezoelectric media decaying states regular states

P_(4k-1)-factorization of complete bipartite graphs

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Science china Mathematics 2005年第4期48卷 539-547页

作者： DU Beiliang & WANG Jian Department of Mathematics, Suzhou University, Suzhou 215006, china Nantong Vocational college, Nantong 226007, china 1. Department of Mathematics Suzhou University 215006 Suzhou China 2. Nantong Vocational college 226007 Nantong China

Let Km,n be a complete bipartite graph with two partite sets having m and n vertices, respectively. A Pv-factorization of Km,n is a set of edge-disjoint pv-factors of Km,n which partition the set of edges of Km,n. When v is an even number, Wang and Ushio gave a necessary and sufficient condition for the existence of Pv-factorization of Km,*** v is an odd number, Ushio in 1993 proposed a conjecture. However, up to now we only know that Ushio Conjecture is true for v = 3. In this paper we will show that Ushio Conjecture is true when v = 4k - 1. That is, we shall prove that a necessary and sufficient condition for the existence of a P4k-1-factorization of Km,n is (1) (2k - 1)m ≤ 2kn, (2) (2k -1)n≤2km, (3) m + n ≡ 0 (mod 4k - 1), (4) (4k -1)mn/[2(2k -1)(m + n)] is an integer.

关键词： complete bipartite graph, factorization, Ushio Conjecture.

RBF neural network and active circles based algorithm for contours extraction

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Progress in Natural Science:Materials International 2007年第6期17卷 681-686页

作者： Zhou Zhiheng, Zeng Delu and Xie Shengli(college of Electronic & Information Engineering, South china University of Technology, Guangzhou 510640, china) college of Electronic and Information Engineering South China University of Technology Guangzhou 510640 China

For the contours extraction from the images, active contour model and self-organizing map based approach are popular nowadays. But they are still confronted with the problems that the optimization of energy function will trap in local minimums and the contour evolutions greatly depend on the initial contour selection. Addressing to these problems, a contours extraction algorithm based on RBF neural network is proposed here. A series of circles with adaptive radius and center is firstly used to search image feature points that are scattered enough. After the feature points are clustered, a group of radial basis functions are constructed. Using the pixels’ intensities and gradients as the input vector, the final object contour can be obtained by the predicting ability of the neural network. The RBF neural network based algorithm is tested on three kinds of images, such as changing topology, complicated background, and blurring or noisy boundary. Simulation results show that the proposed algorithm performs contours extraction greatly.

关键词： contours extraction RBF neural network dynamic clustering.

Study on Tibetan Chicken embryonic adaptability to chronic hypoxia by revealing differential gene expression in heart tissue

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Science china(Life Sciences) 2009年第3期52卷 284-295页

作者： LI Mei & ZHAO ChunJiang college of Animal Science and Technology,china Agricultural University,Beijing 100193,china 1. college of Animal Science and Technology China Agricultural University Beijing 100193 China

Oxygen concentration is essential for appropriate *** can exert a significant impact on physiological alteration of the cell and *** Chicken(Gallus gallus) is a Chinese indigenous breed inhabiting in Tibetan areas,which is also a chicken breed living at high altitude for the longest time in the *** has developed an adaptive mechanism to hypoxia,which is demonstrated by that Tibetan Chicken has much higher hatchability than low-land chicken breeds in high-altitude areas of *** the present study,Tibetan Chicken fertilized full sib eggs were incubated up to Hamburger-Hamilton stage 43 under 13% and 21% oxygen concentration,*** Chicken and Dwarf Recessive White Chicken were used as control *** hearts in all of the 3 chicken breeds under hypoxic and normoxic conditions were isolated and hybridized to Genechip Chicken Genome Array to study molecular mechanisms underlying the adaptation to high altitude of Tibetan *** a result,50 transcripts highly expressed in hypoxia are screened *** up-regulated genes,some are involved in the gene ontology(GO) such as cell growth,cell difference,muscle contraction and signal ***,the expression levels of 21 transcripts are lower in hypoxia than those in *** down-regulated genes take part in cell communication,ion transport,protein amino acid phosphorylation and signal ***,gene enrichment analyses of these differential gene expressions are mainly associated with immune system response and ion channel activity in response to ***,the transcriptional expression profiles analyzed by hierarchical clustering and CPP-SOM software in all of the 3 different chicken breeds revealed that Tibetan Chicken is much closely related to Shouguang Chicken rather than Dwarf Recessive White *** addition,12 transcripts of Tibetan Chicken breed-specific expressed genes were identified,which seem to result in a more

关键词： adaptation chronic hypoxia gene chip chicken genome array Tibetan Chicken(Gallus gallus) differential gene expression

On adjacent-vertex-distinguishing total coloring of graphs

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Science china Mathematics 2005年第3期48卷 289-299页

作者： ZHANG Zhongfu, CHEN Xiang’en, LI Jingwen, YAO Bing, LU Xinzhong & WANG Jianfang college of Mathematics and Information Science, Northwest Normal University, Lanzhou 730070, china Department of Computer, Lanzhou Normal college, Lanzhou 730070, china Institute of Applied Mathematics, Lanzhou Jiaotong University, Lanzhou 730070, china college of Information and Electrical Engineering, Lanzhou Jiaotong University, Lanzhou 730070, china Institute of Applied Mathematics, Chinese Academy of Sciences, Beijing 100080, china 1. college of Mathematics and Information Science Northwest Normal University 730070 Lanzhou China 2. Department of Computer Lanzhou Normal College 730070 Lanzhou China 3. Institute of Applied Mathematics Lanzhou Jiaotong University 730070 Lanzhou China 4. college of Information and Electrical Engineering Lanzhou Jiaotong University 730070 Lanzhou China 5. Institute of Applied Mathematics Chinese Academy of Sciences 100080 Beijing China

In this paper, we present a new concept of the adjacent-vertex-distinguishing total coloring of graphs (briefly, AVDTC of graphs) and, meanwhile, have obtained the adjacent-vertex-distinguishing total chromatic number... 详细信息

关键词： graph, proper total coloring, adjacent-vertex-distinguishing total coloring, adjacent-vertex-distinguishing total chromatic number.

Modified adaptive controller for synchronization of incommensurate fractional-order chaotic systems

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Chinese Physics B 2012年第3期21卷 126-130页

作者： Zhang Ruo-Xun (张若洵) college of Elementary Education, Xingtai University, Xingtai 054001, china college of Physics Science and Information Engineering Hebei Normal University Shijiazhuang 050016 China college of Elementary Education Xingtai University Xingtai 054001 China

We investigate the synchronization of a class of incommensurate fractional-order chaotic systems, and propose a modified adaptive controller for fractional-order chaos synchronization based on the Lyapunov stability theory, the fractional order differential inequality, and the adaptive strategy. This synchronization approach is simple, universal, and theoretically rigorous. It enables the synchronization of O fractional-order chaotic systems to be achieved in a systematic way. The simulation results for the fractional-order Qi chaotic system and the four-wing hyperchaotic system are provided to illustrate the effectiveness of the proposed scheme.

关键词： synchronization modified adaptive controller incommensurate fractional-order chaotic system

yellow^0,a marker for low body weight in Drosophila melanogaster

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Science china(Life Sciences) 2009年第7期52卷 672-682页

作者： Li XinHai & Deng XueMei college of Animal Science and Technology,china Agricultural University,Beijing 100193,china 1. college of Animal Science and Technology China Agricultural University Beijing 100193 China

Marker-assisted selection(MAS) is an important modern breeding technique,but it has been found that the effect of the markers for quantitative trait loci(QTL) is inconsistent,leading in some cases to MAS failure and raising doubts about its *** the model organism Drosophila melanogaster was employed to study whether an effective marker could be found and applied to *** crossed the stock carrying the y0 marker(a recessive mutation allele of the yellow gene on the X chromosome) with three other stocks carrying corresponding wild-type markers in an F2 design,and found that the y0 marker was in significant association with low body weight(P<0.001).This association was consistent across different backgrounds and the marker effects in female and male were approximately 0.95 σP(phenotypic standard deviation) and 0.68 σP,*** next introgressed a fragment via the y0 marker into a wild stock background over 20 generations of marker-assisted introgression(MAI),and constructed the introgression stock y0(OR)20 in which body weight decreased by 13% and 7%,in female and male,respectively,compared to the wild stock(P<0.0001).This indicated that there must be a single QTL for low body weight that is tightly linked to the y0 *** then shortened the introgressed fragment to less than 1.5 cM by a deeper MAI using the y0 marker and the white *** narrower fragment also resulted in a similar decrease in body weight to that induced by y0(OR)20,indicating that the QTL for low body weight is located within this less-than-1.5 cM *** characteristics of the y0 marker by PCR amplification and Southern blotting revealed that yellow gene was deficient in the y0 stock,leading to disappearance of melanin from the cuticle and probably influencing the developmental *** above results confirmed the existence of effective QTL markers applicable to MAS breeding schemes,and their potential application in breeding new stocks.

关键词： Drosophila low body weight yellow quantitative trait loci marker-assisted selection introgression