• The korean journal of orthodontics
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• v.27 no.5 s.64
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• pp.669-682
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• 1997

[$Bj\ddot{o}rk$] and Skieller concluded after following facial growth patterns using implants in upper and lower jaw bones that stable structures, which are not influenced by the growth do exist and so these must be the reference landmarks in the process of superimposition. In spite of such facts, for the last 40 years since the discovery of stable structures, most orthodontists have preferred best fit superimposition method to structural method. Cases such as Angle's Class II division 2 malocclusion that show characteristic forward and upward growth or one under long period of post-treatment observation demonstrate that distinct differences exist between the two methods of superimposition. Today, ethical concerns prohibit further growth studies that use implants, md so there is no choice but to use stable structural superimposition method based on $Bj\ddot{o}rk's$ data. Thus, to encourage clinical use of stable structural superimposition method, logic for the use of stable structural superimposition method will be demonstrated, and its technical methods of application will be introduced step by step.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.36 no.10
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• pp.979-987
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• 2008

In aerospace structural design, the position of lightening hole is often required to be optimized from the initial design in order to avoid an excessive stress concentration. To remodel the updated configuration in optimization procedure, re-meshing procedure is conventionally adopted. However, this approach is time-consuming, and has limitations especially in handling hexahedral or quadrilateral meshes, which are preferred because of their good numerical performances. To attenuate these disadvantages, new optimization scheme is proposed by combining the MLS(Moving Least Squares) based overset method and the genetic algorithm in this work. To test the validity of the proposed optimization scheme, optimizations of positions of lightening holes in 2D structures have been carried out.

• Transactions of the Korean Society of Mechanical Engineers
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• v.11 no.1
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• pp.26-35
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• 1987

As an attempt to make the multi-objection for the line design of the rope way, the resulted formulas from the catenary curve as exact ones were summarized, and it was found out that the Kuhn-Tucker's optimality conditions and regions of the objective functions can analytically be expressed with dimensionless parameters. The Pareto's optimum solution set was analytically obtained through the objective function-the minimum relation of $W^{*}$, and $W^{*}$ is a trade-off relation. From this, The dimension of a rope and the value of an initial tension that are the standard in design of the rope way were determined. It was concluded that $V^{*}$ should become minimum, and that the ratio of the dimension of rope to the value of and initial tension become larger than superposition factor corresponding to curve AB.to curve AB.

• Proceedings of the KIEE Conference
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• 1999.07g
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• pp.3153-3155
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• 1999

최근 수년간 의료영상분야는 국내외적으로 급격한 발전을 거듭하고 있다. 특히 자기공명영상장치 (Magnetic Resonance Imaging), X-ray CT(Computed Tomography)와 단층촬영장치는 인체내부를 비침습적(non-invasive)으로 영상화함으로써 해부학적인 질병진단에 많은 장점을 가지고 있다. 이와같은 단층영상 재구성에는 역매트릭스법(matrix inversion). 반복재구성법(interative method), 역투영 법(back-projection), 2차원 Fourier 변환법(2D FFT), 중첩재구성법(Filtered back-projection) 등의 다양한 알고리즘을 사용하고 있다. 본 연구에서는 X-ray CT에서의 단층영상재구성 기법 중 널리 사용되고 있는 Filtered Back Projection 기법의 연산순서도와 연산량을 분석하고 이를 시뮬레이션을 통하여 확인하고 실시간 영상재구성을 위하여 범용 Digital Signal Processor의 병렬처리시스템 구성에 기반된 최적 Architecture를 선정하고자 한다.

• Proceedings of the Korean Information Science Society Conference
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• 2000.04b
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• pp.583-585
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• 2000

본 논문에서는 적은 수의 특징점을 이용한 얼굴 복원 방법을 제안한다. 먼저 얼굴을 형태와 질갑 프로토타입들의 선형 중첩으로 모형화한 다음, 특징점에서의 형태와 질감정보만을 가지고 각각의 얼굴이 요구하는 변형의 근사값을 찾는다. 본 논문에서는 이러한 under-determined 조건에서 최소 제곱법(least square minimization method)을 사용하여 최적값을 얻는다. 실험을 통하여 적은 수의 특징점을 이용하여 2차원 얼굴 영상을 효율적으로 복원할 수 있음을 검증하였다. 우리는 제안된 얼굴 영상을 압축하거나 겹침이나 잡영에 의해 손상된 영상으로부터 원래의 전체 정보를 복원하는데 중요한 역할을 할 수 있을 것으로 기대한다.

• 유체기계공업학회:학술대회논문집
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• 2001.11a
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• pp.293-299
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• 2001

Since the previous cut-and-try design algorithm require much cost and time, it has recently been concerned the automatic design technique using the CFD and optimum design algorithm. In this study, the Navier-Stokes equations is solved to consider the more detail viscous flow informations of cascade interaction and O-H multiblock grid system is generated to impose an accurate boundary condition. The cubic-spline interpolation is applied to handle a relative motion of a rotor to the stator. To validate present procedure, the time averaged aerodynamic loads are compared with experiment and good agreement obtained. Once the N-S equations have been solved, the computed aerodynamic loads may be used to computed the sensitivities of the aerodynamic objective function. The Modified Method of feasible Direction(MMFD) is usef to compute the

• Journal of the Korean Society of Propulsion Engineers
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• v.8 no.2
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• pp.25-31
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• 2004

This paper describes a new vibration-suppression technique for flexible cantilevered structures by using a pipe containing an internal flow. The stability and dynamic response are analyzed based on the finite element method. The flutter limit and optimum stabilizing fluid velocity are determined in root locus diagrams. The impulse responses of the system are studied by the mode superposition method to observe the damping rate of the motion. The stabilizing effect of an internal flow is demonstrated by impulse responses of the structures with and without an material damping. It is found that the response of the pipe with flow of liquid has a larger effect of, stabilizing than that with flow of gas.

• Journal of Internet Computing and Services
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• v.11 no.1
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• pp.35-48
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• 2010

For the next generation mobile communication system, diverse wireless network techniques such as beyond 3G LTE, WiMAX/WiBro, and next generation WLAN etc. are proceeding to the form integrated into the All-IP core network. According to this development, Beyond 3G integrated into heterogeneous wireless access technologies must support the vertical handover and network to be used of several radio networks. However, unified management of each network is demanded since it is individually serviced. Therefore, in order to solve this problem this study is introducing the theory of Common Radio Resource Management (CRRM) based on Generic Link Layer (GLL). This study designs the structure and functions to support the vertical handover and propose the vertical handover algorithm of which policy-based and MCDM are composed between LTE and WLAN systems using GLL and CRRM. Finally, simulation results are presented to show the improved performance over the data throughput, handover success rate and the system service cost.

• Journal of the Korea Institute of Military Science and Technology
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• v.26 no.3
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• pp.205-213
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• 2023

An optimal design of a simple beam-shaped flexure hinge mount supporting an optical mirror is presented. An optical mirror assembly is an opto-mechanically coupled system as the optical and mechanical behaviors interact. This side-supporting mount is flexible in the radial direction and rigid for the remaining degrees of freedom to support the mirror without transferring thermal load. Through thermo-elastic, optical and eigenvalue analysis, opto-mechanical performance was predicted to establish the objective functions for optimization. The key design parameters for this flexure are the thickness and length. To find the optimal values of design parameters, response surface analysis was performed using the design of experiment based on nested FCD. Optimal design candidates were derived from the response surface analysis, and the optimal design shape was confirmed through Opto-mechanical performance validation analysis.

• 한국HCI학회:학술대회논문집
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• 2006.02a
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• pp.1361-1366
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• 2006

본 논문에서는 제약되지 않은 카메라에서 얻어진 회전과 크기 변화를 가진 영상들을 특징 기반의 보로노이 거리 매칭 방법을 이용하여 고속으로 합성 하는 기법에 관해 기술한다. 기존의 특징점 기반 매칭 기법들이 사람의 개입에 의해 영상을 정합하거나, 크기나 회전 변화를 고려하지 않은 형태의 영상들을 처리하는 것과 달리 회전이나 크기변화요소가 포함된 입력영상들을 사람의 개입이 없이 자동으로 정확한 중첩영역을 빠르게 검색하는 방법을 제안한다. 제안된 방법은 우선 영상내의 특징 점들의 위상 정보와 특징 점들 사이의 거리 정보를 가지는 보로노이 거리 정합법을 통해 대응점을 구하고, 찾아진 대응 쌍들을 이용하여 2차원 투영의 초기 변환행렬을 구한다. 다음으로 비선형 이승오차 최적화 알고리즘을 이용하여 최적의 변환 행렬을 구한 후, 마지막으로 구해진 변환 행렬을 이용하여 영상을 합성한다. 실험결과를 통해 본 논문에서 제안한 방법의 효율성을 보인다.