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Adjoint method for the optimum planning of industrial pollutant sources

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Science china Earth sciences 2005年第8期48卷 1270-1279页

作者： LIU Feng1,2. HU Fei2.& ZHU Jiang2.1. College of Environmental sciences, Peking University, beijing 100871,{2. 2. LAPC, institute of Atmospheric physics, chinese academy of sciences, beijing 10002.,{2. 1. College of Environmental sciences Peking University 100871 Beijing China 2. LAPC Institute of Atmospheric Physics Chinese Academy of Sciences 100029 Beijing China

The optimum planning of industrial pollutant sources, which optimizes the economic object without violating environmental constraints, is an important and hard task to be conquered. In this paper, an adjoint method is developed to solve the problem. The penalty function is in-troduced to deal with the environmental inequality constraints, and Lagrange function is con-structed to derive the adjoint equation and the gradient of the object function. In this means, the gradient of the object function can be calculated by solving the adjoint equation, and the infor-mation from the gradient is used to make the object function descend and approach to an optimal solution after some iterations. A two-dimensional, simplified model is used for numerical experi-ments. The theoretical derivations are verified by the results of the experiments. Furthermore, the adjoint method is shown to be of excellent convergence and efficiency, which is adaptive to the fast development of air quality numerical models and super computers.

关键词： optimum planning, industrial pollutant sources, adjoint equation, penalty function, gradient.

High Throughput SNP Genotyping with Two Mini-sequencing Assays

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Acta Biochimica et Biophysica Sinica 2004年第6期36卷 379-384页

作者： Chunqing LUO1,2., Libin DENG1#, and Changqing ZENG1,2. The institute of Genetic and Developmental Biology, the chinese academy of sciences, {2. 100101, china 2.2. Genomics institute, the chinese academy of sciences, {2. 101300, china The institute of Genetic and Developmental Biology the Chinese Academy of SciencesBeijing 100101 China beijing Genomics institute the Chinese Academy of SciencesBeijing 101300 China

Two mini-sequencing methods, FP-TDI (template-directed dye-terminator incorporation with fluorescence-polarization) and MassArray (matrix assisted laser desorption ionization time of flight detection mass spectrometry), were optimized. A numeric standard was introduced to evaluate the SNP scoring quality of FP-TDI assay, thus made the optimization work easier. At the same time, using multi-PCR technology, 8-plex genotyping of MassArray assay was successfully carried out, some softwares were developed and the data process of MassArray was highly automated. Then these two methods were applied to high throughput SNP genotyping, the accuracy, efficiency and robustness were compared. The result shows FP-TDI is more sensitive to the concentration of SNPprimer and PCR product, as well as extension cycles, the SNPprimer length of FP-TDI should be 2.–30 bp long, whereas MassArray assay prefers to be as short as only 16 *** 6440 SNP sites of human chromosome 3 were genotyped in a sample of 90 individuals, 4792.sites by FP-TDI assay and 1648 sites by MassArray assay, the success rates of FP-TDI and MassArray were 67.7% and 93.6% respectively. The throughput of MassArray was higher than FP-TDI, and the cost of MassArray was lower, MassArray was more suitable for high throughput SNP genotyping.

关键词： SNP genotyping FP-TDI MassArray high throughput

SOLVING INTEGRAL EQUATIONS WITH LOGARITHMICKERNEL BY USING PERIODIC QUASI-WAVELETSOLVING INTEGRAL EQUATIONS WITH LOGARITHMICKERNEL BY USING PERIODIC QUASI-WAVELET

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Journal of Computational Mathematics 2000年第5期18卷 487-512页

作者： Han-lin Chen,Si-long Peng (institute of Mathematics, chinese academy of sciences,{2., china) 中科院数学所北京 100080

In solving integral equations with logarithmic kernel which arises from the boundary integral equation reformulation of some boundary value problems for the two dimensional Helmholtz equation, we combine the Galerkin method with Beylkin's ([2.) approach, series of dense and nonsymmetric matrices may appear if we use traditional method. By appealing the so-called periodic quasi-wavelet (PQW in abbr.) ([5]), some of theme matrices become diagonal, therefore we can the a algorithm with only O(K(m)2. arithmetic operations where m is the highest level. The Galerkin approximation has a polynomial rate of convergence.

关键词： Periodic Quasi-Wavelet Integral equation Multiscale.

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(r,k)-catching code

chinese Science Bulletin 1998年第10期43卷 812-815页

作者： LI Anping institute of Applied Mathematics, chinese academy of sciences,{2., china institute of Applied Mathematics Chinese Academy of Sciences Beijing China

A collection of r_words on an alphabet of n letters is called (r,k)_catching code if for every r_word w there is one selected member v such that v coincides with w in at least k places. How large is the smallest size of the (r,k)_catching code and how to find the minimal (r,k)_\%catching code? Some methods are advanced to construct such codes.

关键词： catching code.

Ab-initio molecular dynamics simulation on nano-system under external pressure

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Science china Mathematics 2004年第z1期47卷 92-100页

作者： Jl Min, SUN Deyan & GONG XingaoSurface physics Laboratory and Department of physics, Fudan University, Shanghai 2.0433,{2. institute of Solid State physics, chinese academy of sciences, Hefei 2.0031,{2. Interdisciplary Center for Theoretical studies, chinese academy of sciences, beijing 100080,{2. Fudan Univ Surface Phys Lab Shanghai 200433 Peoples R China Fudan Univ Dept Phys Shanghai 200433 Peoples R China chinese Acad Sci Inst Solid State Phys Hefei 230031 Peoples R China chinese Acad Sci Interdisciplinary Ctr Theoret Studies Beijing 100080 Peoples R China

A new constant-pressure molecular dynamics (MD) method is developed to simulate the dynamic behavior and structure transition of finite system under external pressure. In this method, no artificial parameter is introduced and the computation overheads are very small. As an application, a hard-soft transition of single wall carbon nanotube (SWCNT) under external pressure is found, which is in agreement with the experiments.

关键词： phase transition, simulation, nano-particles

MODELLING AND NUMERICAL SOLUTIONS OF A GAUGE PERIODIC TIME DEPENDENT GINZBURG-LANDAU MODEL FOR TYPE-Ⅱ SUPERCONDUCTORS

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Journal of Computational Mathematics 1997年第4期15卷 365-384页

作者： Zhi-ming Chen (institute of Mathematics, chinese academy of sciences, {2., china) 中科院数学所北京

In this paper we seek the solutions of the time dependent Ginzburg-Landau model for type-Ⅱ superconductors such that the associated physical observables are spatially periodic with respect to some lattice whose basic lattice cell is not necessarily rectangular. After appropriately foring the gange, the model can be formulated as a system of nonlinear parabolic partial differential equations with quasi-periodic boundary conditions. We first give some results concerning the existence, uniqueness and regularity of solutions and then we propose a semiimplicit finite element scheme solving the system of nonlinear partial dmerential equations and show the optimal error estimates both in the L2.and energy *** also report on some numerical results at the end of the paper.

关键词： Math QT MODELLING AND NUMERICAL SOLUTIONS OF A GAUGE PERIODIC TIME DEPENDENT GINZBURG-LANDAU MODEL FOR TYPE SUPERCONDUCTORS

Strengthening of the boreal winter Hadley circulation and its connection with ENSO

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Progress in Natural Science:Materials International 2007年第11期17卷 1327-1333页

作者： Ma Jie1,2.and Li Jianping2.1. College of Atmospheric sciences, Lanzhou University, Lanzhou 730000, china 2. LASG, {2. of Atmospheric physics, chinese academy of sciences, beijing 10002., china) College of Atmospheric sciences Lanzhou University Lanzhou 730000 China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Empirical orthogonal function (EOF) analysis is carried out for the year-to-year variability of the boreal winter (DJF) mass stream function of the mean meridional circulation (MMC) during the period 1948—2.05. The results demonstrate that it is dominated by the equatorially asymmetric and symmetric modes. Further analysis shows that the former mode is linked with the boreal winter Hadley cell mainly on the decadal time-scale, and the latter on the interannual time-scale. The asymmetric mode index (AMI) with a clear upward trend contributes to the decadal strengthening of the boreal Hadley circulation, and is closely correlated with the tropical SST warming, especially in the region of Indo-west Pacific warm pool (INWP). Furthermore, the AMI also contributes to the abrupt change of the correlation coefficient between the boreal Hadley circulation and ENSO after 1976. The symmetric mode index (SMI) with robust and stable linkage with ENSO shows a significant interannual variability, suggesting that the variability of the Hadley circulation is mainly associated with ENSO on the interannual time-scale.

关键词： the Hadley circulation interannual time-scale decadal time-scale

Difference discrete connection and curvature on cubic lattice

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Science china Mathematics 2006年第11期49卷 1458-1476页

作者： WU Ke, ZHAO Weizhong & GUO Hanying Department of Mathematics, Capital Normal University, beijing 100037, china {2. of Theoretical physics, chinese academy of sciences, beijing 100080, china 1. Department of Mathematics Capital Normal University Beijing 100037 China 2. institute of Theoretical physics Chinese Academy of Sciences Beijing 100080 China

In a way similar to the continuous case formally, we define in different but equivalent manners the difference discrete connection and curvature on discrete vector bundle over the regular lattice as base space. We deal with the difference operators as the discrete counterparts of the derivatives based upon the differential calculus on the lattice. One of the definitions can be extended to the case over the random lattice. We also discuss the relation between our approach and the lattice gauge theory and apply to the discrete integrable systems.

关键词： discrete connection, discrete curvature, noncommutative calculus, lattice gauge theory, discrete Lax pair.

Local canonical correlation coefficients and canonical variables of groups of random variables

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chinese Science Bulletin 1998年第10期43卷 815-817页

作者： XU Xingzhong institute of Systems Science, chinese academy of sciences,{2., china institute of Systems Science Chinese Academy of Sciences Beijing China

The concepts of local correlation coefficient, local canonical correlation coefficients and local canonical variables of groups of random variables are defined, which generalize the classical concepts in two groups of random *** concepts together with total corresponding concepts clarify the correlativity among groups of random variables.

关键词： groups of random variables covariance matrix local canonical correlation coefficients local canonical variables.