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A mathematical model for DNA computing using the recombination behavior of DNA molecules, known as a sticker system, has been introduced in 1998. In sticker system, the sticker operation is based on the Watson-Crick complementary feature of DNA molecules. The computation of sticker system starts from an incomplete double-stranded sequence. Then by iterative sticking operations, a complete double-stranded sequence is obtained. It is known that sticker systems with finite sets of axioms and sticker rule (including the simple regular sticker system) generate only regular languages. Hence, different types of restrictions have been considered to increase the computational power of the languages generated by the sticker systems. In this paper, we study the properties of probabilistic simple regular sticker systems. In this variant of sticker system, probabilities are associated with the axioms, and the probability of a generated string is computed by multiplying the probabilities of all occurrences of the initial strings. The language are selected according to some probabilistic requirements. We prove that the probabilistic enhancement increases the computational power of simple regular sticker systems. [ABSTRACT FROM AUTHOR]

Several areas of applications, such as model order reduction, preconditioner design, and eigenvalue problems for spectral projectors can be found in the literature. In this paper, a fast and sparsity preserving approach for computing the spectral projectors is proposed. The suggested approach can be used in both Newton iteration and integral representation based methods. A comparison of the original and the suggested approaches in terms of computation time, sparsity preservation and accuracy is presented in this paper. [ABSTRACT FROM AUTHOR]

Integer goal programming problems arise quite naturally in many real-world applications. In this paper, we propose a reference direction approach and interactive algorithm to solve integer goal programming problem. We use analytic hierarchy process (AHP) to get the reference direction. At each iteration, only one integer linear programming problem is solved to get an efficient solution. Through analytic hierarchy process the decision maker has to provide the preference point such that the original problem has been transformed into linear integer programming model. [ABSTRACT FROM AUTHOR]

This paper describes a subdivision method for surface smoothing. It generates surfaces defined by a non-structured net of vertices. The vertex net does not need to have a regular rectangular grid as most surface modeling methods but can be of any topology and with a variety of n-sided faces. After a small number of iterations the method produces smooth surfaces which are defined by the initial vertex net. [ABSTRACT FROM AUTHOR]

In this paper the Fast-Means algorithm, an enhanced version of the K-Means algorithm; inspired by the Early Classification algorithm; is presented. After analyzing the Early Classification algorithm it was found that the higher centroid displacement at each iteration can be used as mean to define whether an object remains in the same cluster for subsequent iterations, also we found that the reduction strategy can be applied from the beginning to the end of the algorithm execution unlike the Early Classification algorithm where the strategy is applied from the second to the last iteration. Results show that the Fast-Means outperforms the standard version because it reaches a time reduction up to 99.02% with only a quality reduction of 7.62% for the Transaction dataset. Additionally, Fast-Means compared to Early Classification reached an improvement in time reduction up to 41.92% with only a difference of 2.73% in quality reduction. [ABSTRACT FROM AUTHOR]

Image blurring is one of the most crucial techniques in image processing and computer vision. The equation used for solving image blurring problem is known as anisotropic diffusion equation. It able to smooth the inner region of the image without blurring the significant part such as fine details and sharp edges. The main purpose of this paper is to examine the efficiency of Accelerated Over Relaxation (AOR) iterative method with two weighted parameters for solving image blurring problems. To do the performance analysis based on the number of iterations and computational time, three iterative methods which are Gauss-Seidel, Succesive Over Relaxation (SOR) and AOR had been examined to produce the same quality image of Jacobi iterative method. Based on numerical results of the experiments taken out, the findings have shown that AOR iteration is slightly better than Gauss-Seidel and SOR iteration in reducing the number of iterations and computational time approximately by 30% and 2% respectively. [ABSTRACT FROM AUTHOR]

Significant advances made in the field of Terahertz Imaging have captured the attention of many applications including industrial NDE, biomedical imaging and homeland security. The NASA spray on foam insulation (SOFI) inspection is one such critical application were Terahertz imaging is used to detect disbonds and delamination between SOFI and the substrate metal (external tank). This paper discusses modeling aspects of the high frequency inspection system. The feasibility of using a simple ray-tracing model is studied. The efficiency of the model is demonstrated by comparing the model prediction with experimental measurements and further using it in an iterative inverse problem scheme for defect reconstruction. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Mathematical model for description of the dynamic processes in liquid crystals under weak mechanical, temperature and electric perturbations was proposed. In this work the parallel computational algorithm for analysis of the influence of electric field on a layer of a liquid-crystal medium is represented. In the exterior part of the layer, a potential of electric field satisfies the Laplace equation, which solution is constructed by the method of straight lines. Inside the layer, the equation taking into account anisotropy of a medium is solved by means of iterative method. In the presence of electric field, the molecules of the crystal experience the action of bulk forces and couple stresses, which can be used as right-hand sides of the basic equations of mathematical model. The algorithm is implemented using the CUDA technology for computer systems with graphics accelerators. Parallel program contains modules realizing the method of straight lines with the use of a three-point sweep, the fast Fourier transform and the SLAE solution method by means of the LU-decomposition, the iterative method of solving the equation for potential. [ABSTRACT FROM AUTHOR]

The developed method of iterative optimization of interplanetary missions with the low thrust, using sequence of movement specified mathematical models and design shape spacecraft, is realized. The new articular analytical decision describing planar movement of spacecraft with solar electric propulsion is described, allowing to construct initial approach in the iterative scheme of optimization. Developed a method of modelling and optimization of interplanetary missions ballistic schemes, based on a combination of Pontryagin's maximum principle formalism conditions of transversality and methods of the mathematical programming, allowing to consider restrictions characteristic for concrete interplanetary missions. Recommendations for choice design-ballistic parameters of the interplanetary missions spacecraft, received taking into account features nuclear and solar power plant for missions on delivery of a payload to orbits of Mars, expeditions the Earth-Mars-Earth are received. [ABSTRACT FROM AUTHOR]

Here we present an unusual iterative method to solve a given (possibly ill-conditioned) linear system, which exploits the solution of an associated vectorial differential equation. The aim of this work is to provide insight into an unusual way of building an iterative method, which does not want to compete with already well established iterative methods, but just introduces a different point of view. The presented method is compared with other well known iterative methods and reported numerical results confirm the effectiveness of this approach. [ABSTRACT FROM AUTHOR]

A new numerical method for solving the perpetual case of Ameripean options is proposed. The Ameripean delayed exercise model analyzes a new class of option model with American and ParAsian features. The model is mathematically described by ultraparabolic and parabolic PDE's which are valid over different regions. The perpetual case leads to the parabolic-elliptic twophase Stefan problem with free internal boundary. To deal with the obtained nonlinear problem an iterative numerical method is proposed. Numerical analysis are presented and discussed. [ABSTRACT FROM AUTHOR]