迭代函数法计算稀土串级萃取最优化k值

建立了计算串级萃取最优化k值的迭代函数 :R =c/k +d/(k - 1)。实例应用和分析对比结果表明 ,用该迭代函数来计算串级萃取最优化k值 ,计算简便 。

脑功能光学成像的迭代广义指示函数分析法

在脑光学功能成像领域,由T.Yokoo等人提出的广义指示函数法(Generalized Indicator Functions;G IF)能够在极低信噪比下有效地提取大脑行为模式图.但进一步研究发现,该算法在处理脑功能光学图像序列时存在计算量大的缺点.为解决一问题,本文将W eng等在处理FERET人脸数据库时提出的一种迭代算法与G IF算法相结合,给出了一种迭代格式的G IF算法———RG IF(Recursive G IF),RG IF算法利用迭代计算的特点能大幅削减计算量.利用仿真和实验数据对G IF和RG IF算法进行了对比分析,结果表明RG IF不仅能够大大节省计算时间,同时检测效果与G IF相当.

磁性材料复磁导率的宽带测量及模型

分析了线圈杂散参数对高频下复磁导率测量的影响,指出绕组电阻、寄生电容及漏感会导致传统复磁导率测量方法在高频下误差增大。在此基础上提出了使用单匝全包结构进行复磁导率宽带测量的方法,该方法适用于400 MHz以下频率的复磁导率测量。介绍了复磁导率的常见模型,并分别使用Levy法及有理函数迭代逼近法(IRFA)进行模型参数提取,分析了两种算法的优缺点及应用范围。应用推荐复磁导率测量方法对三种磁性材料进行了复磁导率的测量和建模,结果表明,使用推荐的复磁导率测量方法及数据提取算法,可以较好地实现对磁性材料的小信号建模。

分形理论的发展概况及研究现状

分形理论创始于二十世纪七十年代初期,其研究对象为自然界和现实生活中广泛存在的非规则而具有自相似特性的几何形态。本文对分形理论的产生和发展,分形理论的基本概念,以及其主要研究方法包括L-系统法、迭代函数系统(IFS)法、受限扩散凝聚(DLA)法、粒子系统法等做了介绍,并对对分形的研究领域及分形未来前景作了展望。

A non-monotone Phase-1 method in linear programming

To gain superior computational efficiency, it might be necessary to change the underlying philosophy of the simplex method. In this paper, we propose a Phase-1 method along this line. We relax not only the conventional condition that some function value increases monotonically, but also the condition that all feasible variables remain feasible after basis change in Phase-1. That is, taking a purely combinatorial approach to achieving feasibility. This enables us to get rid of ratio test in pivoting, reducing computational cost per iteration to a large extent. Numerical results on a group of problems are encouraging.

Study on Interaction Between Two Parallel Plates with Iteration Method in Functional Theory

By introducing the functional theory into the calculation of electric double layer （EDL） interaction, the interaction energies of two parallel plates were calculated respectively at low, moderate, and high potentials. Compared with the results of two existing methods, Debye-Hückel and Langmuir methods, which are applicable just to the critical potentials and perform poorly in the intermediate potential, the functional approach not only has much simpler expression of the EDL interaction energy, but also performs well in the entire range of potentials.

Doubly Periodic Wave Solutions of Jaulent-Miodek Equations Using Variational Iteration Method Combined with Jacobian-function Method

One of the advantages of the variational iteration method is the free choice of initial guess. In this paper we use the basic idea of the Jacobian-function method to construct a generalized trial function with some unknown parameters. The Jaulent-Miodek equations are used to illustrate effectiveness and convenience of this method, some new explicit exact travelling wave solutions have been obtained, which include bell-type soliton solution, kink-type soliton solutions, solitary wave solutions, and doubly periodic wave solutions.

Seismic data reconstruction based on iterative linear expansion of thresholds

Based on the compressive sensing,a novel algorithm is proposed to solve reconstruction problem under sparsity assumptions.Instead of estimating the reconstructed data through minimizing the objective function,the authors parameterize the problem as a linear combination of few elementary thresholding functions,which can be solved by calculating the linear weighting coefficients.It is to update the thresholding functions during the process of iteration.The advantage of this method is that the optimization problem only needs to be solved by calculating linear coefficients for each time.With the elementary thresholding functions satisfying certain constraints,a global convergence of the iterative algorithm is guaranteed.The synthetic and the field data results prove the effectiveness of the proposed algorithm.

Iterative Solution for Groundstate of H_2^+ Ion

To solve the wave functions and energies of the groundstate of H＋2 ion an iteration procedure for N- dimensional potentials is applied. The iterative solutions are convergent nicely, which are comparable to earlier results based on variational methods.

Distance-Stability of Nonlinear Discrete Systems

In this paper,the distance-sability of nonlinear discrete system is investigated by means of the Gauss-Seidel iteration method.Some algebric criteria of the distance-stability are ob-tained.Construction of Lyapunov function is avoided.

A modified method to calculate reliability index using maximum entropy principle

Routine reliability index method, first order second moment (FOSM), may not ensure convergence of iteration when the performance function is strongly nonlinear. A modified method was proposed to calculate reliability index based on maximum entropy (MaxEnt) principle. To achieve this goal, the complicated iteration of first order second moment (FOSM) method was replaced by the calculation of entropy density function. Local convergence of Newton iteration method utilized to calculate entropy density function was proved, which ensured the convergence of iteration when calculating reliability index. To promote calculation efficiency, Newton down-hill algorithm was incorporated into calculating entropy density function and Monte Carlo simulations (MCS) were performed to assess the efficiency of the presented method. Two numerical examples were presented to verify the validation of the presented method. Moreover, the execution and advantages of the presented method were explained. From Example 1, after seven times iteration, the proposed method is capable of calculating the reliability index when the performance function is strongly nonlinear and at the same time the proposed method can preserve the calculation accuracy; From Example 2, the reliability indices calculated using the proposed method, FOSM and MCS are 3.823 9, 3.813 0 and 3.827 6, respectively, and the according iteration times are 5, 36 and 10 6 , which shows that the presented method can improve calculation accuracy without increasing computational cost for the performance function of which the reliability index can be calculated using first order second moment (FOSM) method.

Iterative Methods for Parametric Linear Systems with Linear Functions

This paper mainly proposes a new C-XSC （C- for eXtended Scientific Computing） software for the symmetric single step method and relaxation method for computing an enclosure for the solution set and compares the methods with others＇ and then makes some modifications and finally, examples illustrating the applicability of the proposed methods are given.

Free Transverse Vibration Analysis of an Underwater Launcher Based on Fluid-Structure Interaction

A pneumatic launcher is theoretically investigated to study its natural transverse vibration in water. Considering the mass effect of the sealing cover, the launcher is simplified as a uniform cantilever beam with a top point mass. By introducing the boundary and continuity conditions into the motion equation, the natural frequency equation and the mode shape function are derived. An iterative calculation method for added mass is also presented using the velocity potential function to account for the mass effect of the fluid on the launcher. The first 2 order natural frequencies and mode shapes are discussed in external flow fields and both external and internal flow fields. The results show good agreement with both natural frequencies and mode shapes between the theoretical analysis and the FEM studies. Also, the added mass is found to decrease with the increase of the mode shape orders of the launcher. And because of the larger added mass in both the external and internal flow fields than that in only the external flow field, the corresponding natural frequencies of the former are relatively smaller.

Solitary Wave and Wavelet

In this paper,it is shown that the homoclinic orbits exist in iterated functional systems.so do the solitary wave structures.Moreover,Harr father wavelet,Mexican Cap wavelet,and other closed form wavelets have this solitary wave structure,too So wavelet is a certain kind of solitary wave.

Strong Approximation Method and the(Functional)Law of Iterated Logarithm for GI/G/1 Queue

In this paper, a unified method based on the strong approximation(SA) of renewal process(RP) is developed for the law of the iterated logarithm(LIL) and the functional LIL(FLIL), which quantify the magnitude of the asymptotic rate of the increasing variability around the mean value of the RP in numerical and functional forms respectively. For the GI/G/1 queue, the method provides a complete analysis for both the LIL and the FLIL limits for four performance functions: The queue length, workload, busy time and idle time processes, covering three regimes divided by the traffic intensity.

Solution to Nonlinear Parabolic Equations Related to P-Laplacian

Consider the following Cauchy problem：where 1 〈 p 〈 2, 1 〈 m 〈 p_~11, and # is a a-finite measure in N. By the Moser＇s iteration method, the existence of the weak solution is obtained, provided that （M＋1）N 〈 P. In mN＋l contrast, if 〉 p, there is no solution to the Cauchy problem with an initial value δ（X）, where 5（x） is the classical Dirac function.

A learning method for energy optimization of the plug-in hybrid electric bus

The optimal energy management for a plug-in hybrid electric bus(PHEB)running along the fixed city bus route is an important technique to improve the vehicles’fuel economy and reduce the bus emission.Considering the inherently high regularities of the fixed bus routes,the continuous state Markov decision process(MDP)is adopted to describe a cost function as total gas and electric consumption fee.Then a learning algorithm is proposed to construct such a MDP model without knowing the all parameters of the MDP.Next,fitted value iteration algorithm is given to approximate the cost function,and linear regression is used in this fitted value iteration.Simulation results show that this approach is feasible in searching for the control strategy of PHEB.Simultaneously this method has its own advantage comparing with the CDCS mode.Furthermore,a test based on a real PHEB was carried out to verify the applicable of the proposed method.

An Independent Component Analysis Algorithm through Solving Gradient Equation Combined with Kernel Density Estimation

A new algorithm for linear instantaneous independent component analysis is proposed based on maximizing the log-likelihood contrast function which can be changed into a gradient equation.An iterative method is introduced to solve this equation efficiently.The unknown probability density functions as well as their first and second derivatives in the gradient equation are estimated by kernel density method.Computer simulations on artificially generated signals and gray scale natural scene images confirm the efficiency and accuracy of the proposed algorithm.