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Present Algorithm (present + algorithm)
Selected AbstractsVibration analysis of conical panels using the method of discrete singular convolutionINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 3 2008Ömer CivalekArticle first published online: 16 NOV 200 Abstract A discrete singular convolution (DSC) free vibration analysis of conical panels is presented. Regularized Shannon's delta kernel (RSK) is selected as singular convolution to illustrate the present algorithm. In the proposed approach, the derivatives in both the governing equations and the boundary conditions are discretized by the method of DSC. Effects of boundary conditions, vertex and subtended angle on the frequencies of conical panel are investigated. The effect of the circumferential node number on the vibrational behaviour of the panel is also analysed. The obtained results are compared with those of other numerical methods. Numerical results indicate that the DSC is a simple and reliable method for vibration analysis of conical panels. Copyright © 2006 John Wiley & Sons, Ltd. [source] A non-linear fin design problem in determining the optimum shape of spine and longitudinal finsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 2 2003Cheng-Hung Huang Abstract A non-linear fin design algorithm is applied to estimate the optimum shapes for the spine and longitudinal fins by using the conjugate gradient method (CGM) based on the desired fin efficiency and fin volume. One of the advantages in using CGM in the inverse design problem lies in that it can handle problems having a large number of unknown parameters easily and converges very fast. The validity of the present algorithm by using the CGM to solve the non-linear fin design problem is justified based on numerical experiments. Results show that the optimum fin shapes can always be obtained. Copyright © 2003 John Wiley & Sons, Ltd. [source] Discrete singular convolution and its application to the analysis of plates with internal supports.INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 8 2002Part 1: Theory, algorithm Abstract This paper presents a novel computational approach, the discrete singular convolution (DSC) algorithm, for analysing plate structures. The basic philosophy behind the DSC algorithm for the approximation of functions and their derivatives is studied. Approximations to the delta distribution are constructed as either bandlimited reproducing kernels or approximate reproducing kernels. Unified features of the DSC algorithm for solving differential equations are explored. It is demonstrated that different methods of implementation for the present algorithm, such as global, local, Galerkin, collocation, and finite difference, can be deduced from a single starting point. The use of the algorithm for the vibration analysis of plates with internal supports is discussed. Detailed formulation is given to the treatment of different plate boundary conditions, including simply supported, elastically supported and clamped edges. This work paves the way for applying the DSC approach in the following paper to plates with complex support conditions, which have not been fully addressed in the literature yet. Copyright © 2002 John Wiley & Sons, Ltd. [source] Computations of two passing-by high-speed trains by a relaxation overset-grid algorithmINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 12 2004Jenn-Long Liu Abstract This paper presents a relaxation algorithm, which is based on the overset grid technology, an unsteady three-dimensional Navier,Stokes flow solver, and an inner- and outer-relaxation method, for simulation of the unsteady flows of moving high-speed trains. The flow solutions on the overlapped grids can be accurately updated by introducing a grid tracking technique and the inner- and outer-relaxation method. To evaluate the capability and solution accuracy of the present algorithm, the computational static pressure distribution of a single stationary TGV high-speed train inside a long tunnel is investigated numerically, and is compared with the experimental data from low-speed wind tunnel test. Further, the unsteady flows of two TGV high-speed trains passing by each other inside a long tunnel and at the tunnel entrance are simulated. A series of time histories of pressure distributions and aerodynamic loads acting on the train and tunnel surfaces are depicted for detailed discussions. Copyright © 2004 John Wiley & Sons, Ltd. [source] A distributed adaptive guard channel reservation scheme for cellular networksINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 9 2007H.K. Pati Abstract In this paper, a distributed adaptive guard channel reservation (DAGCR) scheme is proposed to give priority to handoff calls. This scheme is built upon the concept of guard channels and it uses an adaptive algorithm to search automatically the optimal number of guard channels to be reserved at each base station. The quality-of-service (QoS) parameters used are the new and handoff call blockings. Simulation studies are performed to compare the present algorithm with the static guard channel policy. Simulation results show that this proposed algorithm guarantees the handoff call blocking probability to remain below the targeted threshold up to a substantially high offered load with a minimal blocking to new calls up to a moderate offered load and also shows significantly high channel utilization in all offered load conditions. This scheme is examined over a wide range of offered load. Thus, it seems the proposed scheme is very useful in controlling the blocking performances in wireless cellular networks. Copyright © 2006 John Wiley & Sons, Ltd. [source] Structural refinement by restrained molecular-dynamics algorithm with small-angle X-ray scattering constraints for a biomoleculeJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 1 2004Masaki Kojima A new algorithm to refine protein structures in solution from small-angle X-ray scattering (SAXS) data was developed based on restrained molecular dynamics (MD). In the method, the sum of squared differences between calculated and observed SAXS intensities was used as a constraint energy function, and the calculation was started from given atomic coordinates, such as those of the crystal. In order to reduce the contribution of the hydration effect to the deviation from the experimental (objective) curve during the dynamics, and purely as an estimate of the efficiency of the algorithm, the calculation was first performed assuming the SAXS curve corresponding to the crystal structure as the objective curve. Next, the calculation was carried out with `real' experimental data, which yielded a structure that satisfied the experimental SAXS curve well. The SAXS data for ribonuclease T1, a single-chain globular protein, were used for the calculation, along with its crystal structure. The results showed that the present algorithm was very effective in the refinement and adjustment of the initial structure so that it could satisfy the objective SAXS data. [source] A simple pharmacokinetics subroutine for modeling double peak phenomenonBIOPHARMACEUTICS AND DRUG DISPOSITION, Issue 3 2006Ahmad Mirfazaelian Abstract Double peak absorption has been described with several orally administered drugs. Numerous reasons have been implicated in causing the double peak. DRUG-KNT,a pharmacokinetic software developed previously for fitting one and two compartment kinetics using the iterative curve stripping method,was modified and a revised subroutine was incorporated to solve double-peak models. This subroutine considers the double peak as two hypothetical doses administered with a time gap. The fitting capability of the presented model was verified using four sets of data showing double peak profiles extracted from the literature (piroxicam, ranitidine, phenazopyridine and talinolol). Visual inspection and statistical diagnostics showed that the present algorithm provided adequate curve fit disregarding the mechanism involved in the emergence of the secondary peaks. Statistical diagnostic parameters (RSS, AIC and R2) generally showed good fitness in the plasma profile prediction by this model. It was concluded that the algorithm presented herein provides adequate predicted curves in cases of the double peak phenomenon. Copyright © 2006 John Wiley & Sons, Ltd. [source] | ||||||||||