• Coupled systems mechanics
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• v.1 no.4
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• pp.325-343
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• 2012

We present different numerical methods for solving the shallow shelf equations with basal drag (SSAB). An alternative approach of splitting the SSAB equation into a Laplacian and diagonal shift operator is discussed with respect to the underlying eigenvalue problem. First, we solve the equations using standard methods. Then, the coupled equations are decomposed into operators for membranes stresses, basal shear stress and driving stress. Applying reasonable parameter values, we demonstrate that the operator of the membrane stresses is much stiffer than the operator of the basal shear stress. Here, we could apply a new splitting method, which alternates between the iteration on the membrane-stress operator and the basal-shear operator, with a more frequent iteration on the operator of the membrane stresses. We show that this splitting accelerates and stabilize the computational performance of the numerical method, although an appropriate choice of the standard method used to solve for all operators in one step speeds up the scheme as well.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2011.07a
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• pp.135-136
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• 2011

Sparse한 신호 복원 방법으로 underdetemined system에서 l1-minimization을 이용한 compressive sensing의 연구와 함께, l1-minimization비해 간단한 greed 알고리듬도 활발히 연구되고 있다. 이에 본 논문은 greed 알고리듬의 대표적인 orthogonal matching pursuit기법에서 iteration 마다 support 선택 개수에 따른 성능을 연구한다. 모의 실험을 통해 OMP의 iteration 단계에서 하나의 support만 선택하는 것보다 다수의 support를 선택하는 것이 더 낮은 sparsity의 신호를 복원할 수 있고 더 낮은 계산량의 이득을 가져오는 것을 확인 할 수 있다.

• Communications of the Korean Mathematical Society
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• v.19 no.1
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• pp.63-74
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• 2004

Suppose that X is a real Banach space, K is a nonempty closed convex subset of X and T : $K\;\rightarrow\;K$ is a uniformly continuous ${\phi}$-hemicontractive operator or a Lipschitz ${\phi}-hemicontractive$ operator. In this paper we prove that under certain conditions the three-step iteration methods with errors converge strongly to the unique fixed point of T. Our results extend the corresponding results of Chang [1], Chang et a1. [2], Chidume [3]-[7], Chidume and Osilike [9], Deng [10], Liu and Kang [13], [14], Osilike [15], [16] and Tan and Xu [17].

• Journal of Satellite, Information and Communications
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• v.11 no.1
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• pp.26-31
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• 2016

In this paper, we proposed a scheme to mitigate noises based on the EMD scheme for heterogeneous communication systems. Noise-corrupted data can be decomposed into a finite number of IMF components. Using the EMD method, we can mitigate noise with eliminate noise-corrupted IMF components. We proposed iteration stop rule for reduce EMD computation time. Simulation results show that proposed EMD scheme based on proposed algorithm for iteration stop rule efficiently mitigates 3 types of noise and reduces its computational time.

• Journal of Navigation and Port Research
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• v.29 no.6 s.102
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• pp.523-528
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• 2005

The flow analysis is made to simulate the turbulent flow in the pipe with an obstacle. The models used are k-$\epsilon$, k-$\omega$, Spalart-Allmaras and Reynolds. The structured grid is used for the simulation The velocity vector, the pressure contour, the change of residual along the iteration number and the dynamic head are simulated for the comparison of four example cases. For the analysis, the commercial code is used.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39A no.9
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• pp.566-568
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• 2014

In this letter, an MMSE based iterative soft decision interference cancellation scheme for massive MIMO systems is proposed. To reduce the complexity, the proposed scheme uses the Sherman-Morrison-Woodbury formula to compute the entire MMSE filtering vectors in one iteration by one matrix inverse operation. Simulation results show that the proposed scheme also has a comparable BER to the conventional scheme for massive MIMO systems.

• Proceedings of the KIEE Conference
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• 1999.11c
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• pp.485-487
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• 1999

We propose the algorithm with which one can solve the problem of the two-level hierarchical optimal control of nonlinear systems by repeatedly updating the state vectors using the haar function and Picard's iteration methods. Using the simple operation of the coefficient vectors from the fast haar transformation in the upper level and applying that vectors to Picard iteration methods in the independently lower level allow us to obtain the another method except the inversion matrix operation of the high dimention and the kronecker product in the optimal control algorithm.

• Kyungpook Mathematical Journal
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• v.52 no.4
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• pp.433-441
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• 2012

We adapt the concept of shrinking projection method of Takahashi et al. [J. Math. Anal. Appl. 341(2008), 276-286] to the iteration scheme studied by Kim and Lee [Kyungpook Math. J. 48(2008), 685-703] for two relatively weak nonexpansive mappings. By letting one of the two mappings be the identity mapping, we also obtain strong convergence theorems for a single mapping with two types of computational errors. Finally, we improve Kim and Lee's convergence theorem in the sense that the same conclusion still holds without the uniform continuity of mappings as was the case in their result.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.34S no.1
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• pp.65-71
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• 1997

In this paper, we propose a new .mu.-controller design method using an equivalent weighting function $W_{\mu}$(s). The proposed mehtod is not guaranteed to converge to the minimum as D-K and .mu.-K iteration method. However, the robust performance problem can be converted into an equivalent $H^{\infty}$ optimization problem of unstructured uncertainty by using an equivalent weightng function $W_{\mu}$(s). Also we can find a .mu.-optimal controller iteratively using an error index $d_{\epsilon}$ of differnce between maximum singular value and .mu.-norm. And under the condition of the same order of scaling functions, the proposed method provides the .mu.-optimal controller with the degree less than that obtained by D-K iteration..

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.2
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• pp.10-14
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• 2014

Krylov-Schur iteration method has been applied to the 2-Dim. waveguides of the varied geometrical structure. The eigen-equations for them have been constructed from FEM based on the tangential edge vectors of triangular elements. The eigen-values and their modes have been determined from the diagonal components of the Schur matrices and its transforming matrices. The eigen-pairs as the results have been revealed visually in the schematic representations.