• Advances in aircraft and spacecraft science
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• v.2 no.3
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• pp.329-343
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• 2015

This study aimed to observe the effect of a novel concept (referred to as the flap extension) implemented on the leading edge of the flap of a three element high lift device. The high lift device, consisting of a flap, main element and slat is designed around an Airbus research profile for sufficient take off and landing performance of a large commercial aircraft. The concept is realised on the profile and numerically optimised to achieve an optimum geometry. Two different optimisation approaches based on Genetic Algorithm optimisations are used: a zero order approach which makes simplifying assumptions to achieve an optimised solution: as well as a direct approach which employs an optimisation in ANSYS DesignXplorer using RANS calculations. Both methods converge to different optimised solutions due to simplifying assumptions. The solution to the zero order optimisation showed a decreased stall angle and decreased maximum lift coefficient against angle of attack due to early stall onset at the flap. The DesignXplorer optimised solution matched that of the baseline solution very closely. The concept was seen to increase lift locally at the flap for both optimisation methods.

• The Transactions of the Korea Information Processing Society
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• v.4 no.7
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• pp.1851-1864
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• 1997

This paper presents an algorithm simplifying the ESOP function by several rules. The algorithm is repeatedly performing operations based on the state of each terms by the product transformation operation of two functions and thus it is simplifying the ESOP function through the reduction of the product terms. Through the minimization of the product terms of the multi-valued input binary multi-output function, an optimization of the input has been done using EXOR PLA with input decoder. The algorithm when applied to four valued arithmetic circuit has been used for a EXOR logic circuit design and the two bits input decoder has been used for a EXOR-PLA design. It has been found from a computer simulation(IBM PC486) that the suggested algorithm can reduce the product terms of the output function remarkably regardless of the number of input variables when the variable AND-EXOR PLA is applied to the poperation circuit.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10a
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• pp.52-55
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• 1996

In this paper, we consider the decentralized reduced-order H$_{\infty}$ controller for the general plant. Simplifying method is suggested for the general plant with the decentralized controller structure. When the controller is reconstructed for the original system, the decentralizability of the controller for the transformed system is generally destroyed with the older method. We solve this problem. For the simplified system, the structure of the decentralized controller is suggested..

• Journal of the Korean Mathematical Society
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• v.52 no.1
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• pp.43-65
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• 2015

We present a new convergence analysis of popular Broyden's method in the Banach/Hilbert space setting which is applicable to non-smooth operators. Moreover, we do not assume a priori solvability of the equation under consideration. Nevertheless, without these simplifying assumptions our convergence theorem implies existence of a solution and superlinear convergence of Broyden's iterations. To demonstrate practical merits of Broyden's method, we use it for numerical solution of three nontrivial infinite-dimensional problems.

• Structural Engineering and Mechanics
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• v.9 no.2
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• pp.141-152
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• 2000

Based on the discussion about some empirical coherency models resulted from earthquake-induced ground motion recordings at the SMART-1 array in Taiwan, and a heuristic model of the coherency function from elementary notions of stationary random process theory and a few simplifying assumptions regarding the propagation of seismic waves, a practical coherency model for spatially varying ground motions, which can be applied in aseismic analysis and design, is proposed, and the regressive coefficients are obtained using least-square fitting technique from the above recordings.

• Proceedings of the IEEK Conference
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• 2000.11c
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• pp.109-112
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• 2000

Many applications in computer graphics require highly detailed complex models. However, the level of detail may vary considerably according to applications. It is often desirable to use approximations in place of excessively detailed models. We have developed a surface simplification algorithm which uses iterative contractions of edges to simplify models and maintains surface error approximations using a quadric metric. In this paper, we present an improved quadric error metric for simplifying meshes. The new metric, based on subdivided edge classification, results in more accurate simplified meshes. We show that a subdivided edge classification captures discontinuities efficiently. The new scheme is demonstrated on a variety of meshes.

• Journal of The Korean Astronomical Society
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• v.8 no.1
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• pp.35-39
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• 1975

Effect of the ratio of mixing length to the pressure scale-height ${\alpha}$=l/HP on the effective temperature has been investigated under some simplifying assumptions. The result is compared with that of the existing model calculations. The role of convection zone in the stellar evolution is briefly summarized.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.139-143
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• 1996

The theoretical study of deformation behavior for continous extrusion process (CONFORM) is shown in this paper. The extrusion process is compared with a conventional route, side extrusion, considering extrusion ratios, flash gaps and coefficients of friction. In each case the distribution of strain and strain rate is predicted by using the finite element method. In this study simplifying assumptions on the deformation geometry are made to investigate the plastic flow occuring in the area of deformation of the Conform process.

• 전기의세계
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• v.25 no.4
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• pp.63-67
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• 1976

A new method for simplifying linear, bilateral and passive networks is presented, and the principle employed is based upon the elimination of mutual impedance and floating nodes of the metwork by introducing incidence matrix notations and bus admittance matrices. The method suggested is, particularly, suited for machine computations and applycable for reducing the calculation time in power system short-circuit and load-flow studies with good results.

• Journal of Ocean Engineering and Technology
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• v.16 no.2
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• pp.10-20
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• 2002

본 논문에서는 바다의 자유표면에서 생성되는 항력에 대한 물리적 특성에 대한 연구가 기술되었다. 2차원 파장(Wave Field) 매개변수해석기법(Parametric Analyzing Technique)을 근거로 한 파경계층(Wave Boundary Layer : WBL)의 1차원 모델로서 항력계산과 파경계층의 특성을 추정하였으며 이론의 간략화(Simplifying)에 대한 연구에 주력하였다.