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Predictor-corrector interior-point algorithm for linearly constrained convex programming

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Journal of Central South university 2001年第3期13卷 208-212页

作者： LIANG Xi-ming (college of information science & {3., Central South university, Changsh a 410083. China) college of information science & {3. Central South University Changsha China

Active set method and gradient projection method are curre nt ly the main approaches for linearly constrained convex programming. Interior-po int method is one of the most effective choices for linear programming. In the p aper a predictor-corrector interior-point algorithm for linearly constrained c onvex programming under the predictor-corrector motivation was proposed. In eac h iteration, the algorithm first performs a predictor-step to reduce the dualit y gap and then a corrector-step to keep the points close to the central traject ory. Computations in the algorithm only require that the initial iterate be nonn egative while feasibility or strict feasibility is not required. It is proved th at the algorithm is equivalent to a level-1 perturbed composite Newton method. Numerical experiments on twenty-six standard test problems are made. The result s show that the proposed algorithm is stable and robust.

关键词： linearly constrained convex programming predictor corrector interior point algorithm numerical experiment

Vision navigation algorithm for mine agent based on quaternion

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中国有色金属学会会刊：英文版 2011年第S3期21卷 610-615页

作者： LI Ke-zhao1, 4, LEI Wei-wei1, 2, GUO Zeng-zhang1, 2, WU Li-xin3. ZHANG Qin4 1. School of Survey and Land information engineering, henan Polytechnic {3., Jiaozuo 454003. China 2. Key Laboratory of Mine Spatial information Technologies of State Bureau of Surveying and Mapping, henan Polytechnic {3., Jiaozuo 454003. China 3. college of Resources and Civil engineering, Northeastern {3., Shenyang 110819, China 4. college of Geology engineering and Geomatics, Chang’an {3., Xi’an 710054, China School of Survey and Land information engineering Henan Polytechnic University Jiaozuo 454003 China college of Geology engineering and Geomatics Chang'an University Xi'an 710054 China Key Laboratory of Mine Spatial information Technologies of State Bureau of Surveying and Mapping Henan Polytechnic University Jiaozuo 454003 China college of Resources and Civil engineering Northeastern University Shenyang 110819 China

Autonomous relative navigation is the key technology in mining or rescuing. On the basis of mine requirement and the theories of machine vision, an autonomous relative navigation algorithm for mine agent based on quaternion was proposed. In rotation transformation, this algorithm was represented by using quaternion. Because the Jacobi matrix of this method is lower than that of Hall algorithm, the calculation efficiency is improved by using this algorithm. The results of these experiments show that the computation burden of this algorithm based on quaternion is about half that of Hall algorithm. This algorithm based on quaternion is improved as a valid way to solve the problem of mine real-time navigation.

关键词： quaternion mine agent vision navigation

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 college of science China Agricultural University Beijing China college of engineering Ocean University of China Qingdao China School of Mechanical engineering University of Science and Technology Liaoning Anshan 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

THE LIMITING CASE OF THIELE'S INTERPOLATING CONTINUED FRACTION EXPANSION

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Journal of Computational Mathematics 2001年第4期19卷 433-444页

作者： Jie-qing Tan (Institute of Applied Mathematics, college of science and CAD/CG Division college of Computer & {3. Hefei, university of technology, Hefei 23.009, China) 中国科学技术大学安徽合肥 230009

By means of the determinantal formulae for inverse and reciprocal differences with coincident data points, the limiting case of Thiele's interpolating continued fraction expansion is studied in this paper and given numerical example shows that the limiting Thiele's continued fraction expansion can be determined once for all instead of carrying out computations for each step to obtain each convergent as done in [3..

关键词： Continued fraction Inverse difference Reciprocal difference Expansion.

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 China college of engineering Ocean University of China Qingdao China School of Mechanical engineering University of Science and Technology of Liaoning Anshan 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

Large eddies induced by local impulse at wall of boundary layer with pressure gradients

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Progress in Natural science:Materials International 2008年第7期18卷 873-878页

作者： Changgen Lu a,b,*, Weidong Caob, Yanmei Zhang b, Jintao Pengb a college of Atmospheric science, Nanjing university of {3. science & technology, Nanjing 210044, China b college of Environmental science and engineering, Hohai university, Nanjing 210098, China college of Atmospheric science Nanjing University of Information Science & Technology Nanjing 210044 China college of Environmental science and engineering Hohai University Nanjing 210098 China

Large eddies induced by local impulse at the wall with pressure gradients in the boundary layer was studied by direct numerical sim- ulations. The results show that the amplitude evolution, the high and low speed stripes, the formation of streamwise vortices, the ejection and sweeping, inflexions and distortion at the mean velocity profiles, as well as other characteristics, are consistent with the experimental and other numerical results. It is also found that large eddies are easy to be excited with adverse pressure gradient in the boundary layer, and the growth of amplitudes, formation of streamwise vortices and the influencing area etc., are much larger than those with favorable pressure gradient in the boundary layer. In contrast, large eddies are hardly to be induced through local impulse disturbance at the wall with favorable pressure gradients in the boundary layer.

关键词： Boundary layer Pressure gradients Impulse Large eddies

Algorithm of graph isomorphism with threedimensional DNA graph structures

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Progress in Natural science:Materials International 2005年第2期15卷 86-89页

作者： LIU Guangwu 1,2*, YIN Zhixiang 1,3. XU Jin1 and DONG Yafei1(1. Department of Control science and engineering, Hua Zhong university of science and technology, Wuhan 43.074, China 2. college of Transportation, Wuhan university of technology, Wuhan 43.063. China 3. Department of Mathematics and Physics, Anhui university of science and technology, Huainan 23.001, China) Dept. of Control science and Eng. Huazhong Univ. of Sci. and Technol. Wuhan 430074 China Coll. of Transportation Wuhan Univ. of Technology Wuhan 430063 China Dept. of Mathematics and Physics Anhui Univ. of Sci. and Technol. Huainan 232001 China

An algorithm for solving the graph isomorphism problem with 3.D DNA structures is proposed in this paper. The k-armed branched junction molecules are used to code k-degree vertices. Double stranded molecules are used to code edges. Then the molecules are mixed in a tube to be ligated. The result can be detected by gel electrophoresis. The time complexity of the algorithm is O(n2), where n is the number of vertices of the graph.

关键词： DNA computing DNA graph structure graph isomorphism

Influence of mesoscale topography on vortex intensity

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Progress in Natural science:Materials International 2008年第1期18卷 71-78页

作者： Zhexian Luo*,Yun Gao Remote Sensing college,Nanjing university of information {3. and technology,Najing 210044,China Remote Sensing college Nanjing University of Information Science and Technology Najing 210044 China

The effect of mesoscale topography on multi-vortex self-organization is investigated numerically in this paper using a barotropic prim- itive equation model with topographic *** the initial field there are one DeMaria major vortex with the maximum wind radius rm of 80 km at the center of the computational domain,and four meso-b vortices in the vicinity of rm to the east of the major vortex center. When there is no topography present,the initial vortices self-organize into a quasi-final state flow pattern,i.e.a quasi-axisymmetric vor- tex whose intensity is close to that of the initial major ***,when a mesoscale topography is incorporated,the spatial scale of the quasi-final state vortex reduces,and the relative vorticity at the center of the vortex and the local maximum wind speed remarkably *** possible mechanism for the enhancement of the quasi-final state vortex might be that the negative relative vorticity lump, generated above the mesoscale topography because of the constraint of absolute vorticity conservation,squeezes the center of positive vorticity towards the mountain slope area,and thus reduces the spatial range of the major ***,because the total kinetic energy is basically conservative,the squeezing directly leads to the concentration of the energy in a smaller area,*** strengthening of the vortex.

关键词： Mesoscale topography Vortex Self-organization Intensity change

A characterization for a graphic sequence to be potentially C_r-graphic

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science China Mathematics 2010年第11期53卷 2893-2905页

作者： YIN JianHua Department of Mathematics, college of information science and {3., Hainan university, Haikou 570228, China Department of Mathematics College of Information Science and Technology Hainan University Haikou China

Let r 3. n r and π = (d1, d2, . . . , dn) be a graphic sequence. If there exists a simple graph G on n vertices having degree sequence π such that G contains Cr (a cycle of length r) as a subgraph, then π is said to be potentially Cr-graphic. Li and Yin (2004) posed the following problem: characterize π = (d1, d2, . . . , dn) such that π is potentially Cr-graphic for r 3.and n r. Rao and Rao (1972) and Kundu (1973. answered this problem for the case of n = r. In this paper, this problem is solved completely.

关键词： graph cycle degree sequence