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1.
A generalized Riemann boundary value problem   总被引:7,自引:0,他引:7  
The generalized Riemann boundary value problem for analytic functions is considered, where the unknown function may have branch points of the second order. Under certain assumptions, its general solution as well as the condition of solvability is obtained when the solution is required to be of finite order at infinity. Foundation item: Supported by the National Natural Science Foundation of China (No. 19871064) Biography: LIU Hua(1971-), male, Ph. D candidate, Research interests being in complex analysis and its applications.  相似文献   

2.
A new point-tree data structure genetic programming (PTGP) method is proposed. For the discontinuous function regression problem, the proposed method is able to identify both the function structure and discontinuities points simultaneously. It is also easy to be used to solve the continuous function’s regression problems. The numerical experiment results demonstrate that the point-tree GP is an efficient alternative way to the complex function identification problems. Foundation item: Supported by the National Natural Science Foundation (60173046) and the Natural Science Foundation of Hubei Province (2002AB040) Biography: Xiong Sheng-wu (1966-), male, Associate professor, research direction: evolutionary computing, parallel computing.  相似文献   

3.
A genetic algorithm on multiple sequences alignment problems in biology   总被引:2,自引:0,他引:2  
The study and comparison of sequences of characters from a finite alphabet is relevant to various areas of science, notably molecular biology. The measurement of sequence similarity involves the consideration of the possible sequence alignments in order to find an optimal one for which the “distance” between sequences is minimum. In biology informatics area, it is a more important and difficult problem due to the long length (100 at least) of sequence, this cause the compute complexity and large memory require. By associating a path in a lattice to each alignment, a geometric insight can be brought into the problem of finding an optimal alignment, this give an obvious encoding of each path. This problem can be solved by applying genetic algorithm, which is more efficient than dynamic programming and hidden Markov model using commomly now. Foundation item: Supported by Zi-qiang Foundation of Wuhan University and Open Foundation of the State Key-Laboratory of Software Engineering, Wuhan University Biography: Shi Feng(1966-), male, Associate professor, research direction: bioinformatics.  相似文献   

4.
A new public key encryption scheme is proposed in this paper, which is based on a hard problem over ergodic matrices. The security of this scheme is equal to the MQ-problem: multivariate quadratic equations over finite fields. This problem has been shown to be NP-complete and can't be solved with polynomial time algorithm.  相似文献   

5.
A RCS prediction system named SCTE (Scattering from Complex Target and Environment) for calculating high-frequency electromagnetic scattering from complex target within complex environment is presented. The scattering body is described by Computer-Aided-Design (CAD) representations in which the complex body is modeled as NURBS (Non-Uniform Rational B-spline) surfaces. The complex environment (rough surface of sea or ground) is also carefully considered by using fractal function. Scattering fields are calculated by using physical optics and the equivalent currents methods. There is a good agreement between the present results and that from measurements which demonstrates the accuracy of this system. Foundation item: Supported by the National Natural Science Foundation of China Biography: CAO Qin-feng (1972-) male, Ph.D. candidate.  相似文献   

6.
Chinese Postman Problem is an unsettled graphic problem. It was approached seldom by evolutionary computation. Now we use genetic algorithm to solve Chinese Postman Problem in undirected graph and get good results. It could be extended to solve Chinese postman problem in directed graph. We make these efforts for exploring in optimizing the mixed Chinese postman problem. Foundation item: Supported by the National Natural Science Foundation of China (60133010, 70071042) Biography: Jiang Hua(1974-), male, Master candidate, research direction: Evolutionary computation.  相似文献   

7.
The pollen of 57 species representing 7 sections of Artemisia was examined hy light microscope and scanning microscope for the purpose to elucidate the systematic relationships of the genus. The examination indicates that the pollen grains present high concordance which is characterized by the globular or the appruximate shape. 3-lobed circular from polar view while granular or ellipse sphere from tropical plate with tricolporate structure. The exinc of pollen has an obvious double structure of inner and outer layers (including the tecturn and columnar layers) where the outer is thicker than the inner and the sculpture of exine degenerates into small spinules easily distinguishable from other genera of the Compositae. Based on cxine sculpture, the pollen grains of Artemisia can be divided into two types: Myriantha type and Mongolica type, which possesses 4 subtypes according to the distribution forms of spinulc: (1) Sacrorum subtype, (2) Oligocarpa subtype, (3) Lavandulaefolia subtype. (4) Anomale subtype.  相似文献   

8.
In the manufacturing grid environment, the span of the consideration of security issues is more extensive, and the solutions for them are more complex, therefore these problems in manufacturing grid can't longer be addressed by existing security technologies. In order to solve this problem, the paper first puts forward the security architecture of manufacturing grid on the basis of the proposal of the security strategies for manufacturing grid; then the paper introduces key technologies based on public key infrastructure-certificate authority (PKI/CA) to ensure the security of manufacturing grid, such as single sign-on, security proxy, independent authentication and so on. Schemes discussed in the paper have some values to settle security problems in the manufacturing grid environment.  相似文献   

9.
双参数弹性地基上自由矩形中厚板问题分析尝试   总被引:2,自引:1,他引:1  
为了解决中厚板与双参数弹性地基的共同作用,基于弹性板理论,推导出中厚板弯曲的一种近似方法,求得了双参数地基上自由矩形中厚板弯曲问题的解析解,对数值算例编程求解,与Winklcr弹性地基上自由矩形中厚板的解进行比较,并与有限元解、差分解、福氏级数解、叠加解和复级数解进行对比,结果十分接近,证明该方法可行。  相似文献   

10.
A trusted third party introduced in watermarking protocols would decrease the security and affect the implementation of the protocols. In this paper, a new watermarking protocol with an un-trusted third party (UTTP) was proposed. Based on the idea of all-or-nothing disclosure of secret (ANDOS), all of the buyer, the seller and the third party didn't know the exact watermark, which was embedded in a digital content for tracing piracy. The proposed protocol provided mechanisms to trace piracy and protect customer's right. In addition, the problem that a seller colluded with UTTP to frame the buyer, namely, the conspiracy problem, could be avoided.  相似文献   

11.
Event correlation is one key technique in network fault management. For the event sample acquisition problem in event correlation, a novel approach is proposed to collect the samples by constructing network simulation platform. The platform designed can set kinds of network faults according to user's demand and generate a lot of network fault events, which will benefit the research on efficient event correlation techniques. Foundation item: Supported by the National Natural Science Foundation of China (69983005) Biography: Su Yu-bei(1972-), male, Ph.D. candidare, research direction: intelligent network fault management.  相似文献   

12.
In this paper, we give a necessary and sufficient condition of sequence of nodes, such that, the error of trigonometric interpolation for analytic function converges to 0. Foundation item: Supported by the Science Foundation of SEC of China and Foundation of Wuhan University Biography: LIU Hua (1971-), male, PH. D candidate, Research interest is in complex analysis.  相似文献   

13.
This paper discusses a re-examinatlon of dual methods based on Gomory's cutting plane for the solution of the integer programming problem, in which the increment of objection function is allowed as a pivot variable to decide the search direction and stepsize. Meanwhile, we adopt the current equivalent face technique so that lattices are found in the discrete integral face and stronger valid inequalities are acquired easily.  相似文献   

14.
Adopting the lifting scheme, introduced by Sweldens, a new wavelet is constructed. It overcomes the shortcoming of the classical wavelets that has no flexibility in the number of vanishing moment. Two examples are given to prove the second-generation wavelets‘s potentialities in the singularity detection of signal: a wavelet with vanishing moment and symmetry can be constructed according to the problem.  相似文献   

15.
The purpose of this paper is to present a new general approach to solve ground-state energies of the double-electron systems in a uniform magnetic field, in which the basic element of evolution is the set in the solution space, rather than the point. The paper defines the Cell Evolutionary Algorithm, which implements such a view of the evolution mechanism. First, the optimal set in which the optimal solution may be obtained. Then this approach applies the embedded search method to get the optimal solution. We tested this approach on the atomic structure, and the results show that it can improve not only the efficiency but also the accuracy of the calculations as it relates to this specific problem. Foundation item: Supported by the opening Foundation of state key Laboratory of Magnetic Resonance and Atomic and Molecular physics, Wuhan Institute of physics, Chinese Academy of Science (981510) Biography: Liu Lian-jun(1946-), female, Associate professor, research direction: atom and molecular physics.  相似文献   

16.
Optical dispersive nonlinearities in Er-doped optical fiber are discussed and measured at the third window wavelength 1.55 μm for optical communications firstly. The experimental method, which is developed by us, is based on dynamic scanning for fixed-point-interference (DSFPI) of two fiber beams. The real part and complex value of the third-order susceptibility at the wavelength are also obtained from the measured Kerr coefficient and nonlinear-absorption coefficient reported elsewhere. Foundation item: Supported by the National Natural Science Foundation of China(69487007) Biography: SONG Qian(1937-), female, Professor. Research direction: nonlinear optics and all-optical communications.  相似文献   

17.
From the Physical Optics theory (PO) and Leontovich Impedance Boundary Condition (IBC), We research RCS reduction (RCSR) of multilayer dielectric and magnetic medium on different shape conductors such as plate, cuboid and cone by use of Matlab programs. Some available RCS data and graph results are given. These show the connection between Radar Absorbent Material (RAM) parameters and the number of layers. In the mean time, the relation between RAM optimized parameters and RCS value is also shown. It has better practical significance. Foundation item: Supported by the National Natural Science Foundation of China(69571021) Biograph: ZHANG Chang-jiang (1968-), male, Master candidate. Research direction: electronic magnetics theory.  相似文献   

18.
Many practical problems in commerce and industry involve finding the best way to allocate scarce resources a-mong competing activities. This paper focuses on the problem of integer programming, and describes an evolutionary soft a-gent model to solve it. In proposed model, agent is composed of three components: goal, environment and behavior. Experimental shows the model has the characters of parallel computing and goal driving. Foundation item: Supported by the National Natural Science Foundation of China( 60205007) , Natural Science Foundation of Guangdong Province(001264), Research Foundation of Software Technology Key Laboratory in Guangdong Province and Research Foundation of State Key Laboratory for Novel Software Technology at Nanjing University Biography: Yin Jian ( 1968-), male, Associate professor, research direction: artificial intelligence, data mining.  相似文献   

19.
The purpose to this paper is to study the existence problem of solutions to the vector quasivariational inequality for vector-valued functions inH-space. Foundation item: Supported by the Science Research Foundation of Xianning Teacher’s College (No. K9911) Biography: Mao Jian-feng (1960-), male, Lecturer, research direction: nonlinear functional analysis.  相似文献   

20.
本文首先用Fourier复级数将非线性问题化为线性问题,从而得到各级近似的边值问题,进而提出圆薄板非轴对称大变形问题的修正迭代法,讨论了圆薄板非轴对称的非线性问题。作为算例,在均变荷载、周边可移夹紧、位移在平面内不受约束的条件下对圆薄板非轴对称的非线性问题进行了求解,并绘出了特征曲线。本文的结果与相应的线性问题进行了比较,证明本文提出的理论和方法是正确的。  相似文献   

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