• The Journal of the Acoustical Society of Korea
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• v.21 no.4
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• pp.415-420
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• 2002

To identify linear parameters of loudspeaker, two methods are presented. Linear parameter identification methods by box method and added mass method are developed. These methods are compared with conventional software to show advantages and disadvantages of developed methods. Results identified by conventional method of Laud software are significantly different from developed methods. But two methods developed show 4% error in Thiele-Small (TS) parameters identified. In box method, it shows that TS parameters are dependent on the amount of porous material.

• Geotechnical Engineering
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• v.12 no.5
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• pp.27-40
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• 1996

Box culvert has long since been used for various purposes , water and sewerage works, communication and electricity facilities, subway, railway, etc. In urban area, the construetion of box culvert generally consists of excavation-installation of the culvert-backfill. However, the existing design methods for earth pressure on the box culvert do not take into account the excavation(or backfill) geometry. ' A new method considering excavation geometry for earth pressure on box culvert is suggested here. The lateral earth pressures by the newly suggested method agree relatively with results of finite element analyses, but those of existing method are greatly overestimated. The vertical pressure on the top of the box culvert by the new method is similar to those of existing method and finite element analysis. However, the reactional pressure on the bottom of the box culvert depends largely upon the stiffness of the foundation soil. The reactional pressure by the new method agrees well with that of finite element analysis, only when the stiffness is low. From the finite element analysis it is shown that the lateral earth pressure on box culvert depends upon the excavated slope (G) and the net bottom distance (Bc).

• Journal of Navigation and Port Research
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• v.40 no.4
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• pp.207-212
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• 2016

The box-counting(BC) method is one of the most commonly used methods for fractal dimension calculation of binary images in the fields of Engineering, Science, Medical Science, Geology, etc due to its simplicity and reliability. It deals with only square images with each size equal to the power of 2 to prevent it from discarding unused pixels for images of arbitrary size. In this paper, we presents a more efficient BC method based on the original one, which is applicable to images of arbitrary size. The proposed approach allows the number of the counting boxes to be real to improve the estimation accuracy. The mean absolute error performance is computed on two deterministic fractal images whose theoretical dimensions are well known to compare with those of the existing BC method and triangular BC method. The experimental results show that the proposed method can outperform the two methods and assess the complexity of coastline images of Korea and Chodo island taken from the Google map.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.6A
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• pp.779-788
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• 2008

In this present study, the three dimensional shell elements analysis method for exact distortional behavior of multicell trapezoidal box girders subjected to an eccentric loading is proposed. In order to perform the independent distortional analysis using shell elements, it is necessary to calculate exact distortional forces. In this study, the force-decomposition equation for applied eccentric load acting on multicell trapezoidal box girder is derived and the equation based on static force equilibrium and superposition theory decompose the eccentric load to the loads cause flexture, torsion and distortion. So by using this force-decomposition equation and shell element analysis, each behavior can be easily analysis independently. This independent analysis method is very useful to physically understand each major behavior of multicell box girder, especially distortional phenomenon. Furthermore, it may be also very useful for designer to perform the independent distortional analysis for diaphragm design using simple 3D shell elements model without preliminary complex calculation for distortional constants.

• Journal of Digital Convergence
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• v.17 no.3
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• pp.73-78
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• 2019

Recently, there is a need to introduce a Korean-style restriction sandbox system that exempts or suspends existing regulations so that new products or services based on new technologies can be commercialized without restrictions. In response, the government reorganized the relevant statutes to promptly check regulations centering on four fields, including industrial convergence, ICT, FinTech, and regional innovation growth, and to allow experimental, proof and market releases by setting certain conditions(zone, period, scale, etc.). However, despite the same regulatory sandbox application, depending on the nature of the field applied, differences in application subject, whether application of regulatory specifics, system of push ahead decision-making and whether support of financial and taxation are shown. This research is intended to present efficient operation measures for successful settling of Korean-style regulation sandboxes by comparing and analyzing, centering on the Industrial Fusion Promotion Act in the Industrial Convergence Field, ICT field's Information and Communication Convergence Act, FinTech field's Financial Innovation Act and Regional Special Zone Act in the Regional Innovation and Growth Sector.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1994.10a
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• pp.111-115
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• 1994

본 연구에서는 보강 되지 않은 사각단면 박스 구조물, 보강된 사각 단면 박스 구조물, 그리고 보강된 요철형 단면 박스 구좀ㄹ에 대하여 양단 고정(clamped-clamped)과 일단 고정 타단 자유(clamped-free)의 경계 조건에 대해 실험적 진동 해석을 수행 하였으며, 유한요소 code인 ANSYS를 이용하여 유한 요소 해석을 수행하였다. 또한 유한 요소 해석과 실험을 통하여 신뢰성이 검증된 요소를 각 박스 구조물에 적용하여 각 경우에 대한 응력해석을 유한요소법을 이용하여 수행하였다. 또한 각각의 경우에 보강재의 개수 및 단면 형상 변화, 그리고 두께 변화가 진동과 응력에 미치는 민감도를 연구하였다.

• ICROS
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• v.18 no.3
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• pp.37-42
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• 2012

이번 편에서는 첫 번째 편에서 소개된 블랙박스 모델을 결정하는 기법 중의 하나인 매개변수 시스템 식별법을 소개한다. 이 기법은 식별하고자 하는 대상 시스템에 대하여 매개변수들로 표현되는 여러 가지 후보 모델들을 선정한 후 확정된 입출력 데이터와 추정 알고리즘을 적용하고 여러 가지 검증과정을 통하여 실제 시스템의 데이터에 가장 가까운 특성을 보이는 모델을 선정하는 방법이다. 이를 위해서 본 편에서는 선형-시불변 시스템의 블랙박스 식별에서 종종 사용되는 여러 가지 모델구조들을 소개한다.

• Proceedings of the Korean Society of Computer Information Conference
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• 2021.01a
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• pp.291-294
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• 2021

본 논문에서는 영어 교육에 대한 사회적인 인식은 중요해지면서 다양한 방식의 영어공부와 학습모델들을 분석하고 오랫동안 가억이 가능한 학습시스템을 검토하였다. 그러나 영어의 기초가 되는 영어 단어의 공부법이 논리적인 근거 없이 강사의 인지도와 명성에 현혹되어 강사가 추천해 주는 공부 방법에 따라 잘못된 학습하는 경우가 대부분이다. 또한 사람마다 자기에게 맞는 학습법은 분명 존재할 것이다. 하지만 그 방법 외에 효과적인 다른 방법 또한 찾아 볼 수 있다. 헤르만 에빙하우스는 사람의 망각 연구한 결과 망각의 주기를 수치로 나타내었고, 라이트너는 플래시 카드를 박스에 넣어 복습을 반복하는 아날로그 장치를 만들어 복습의 효과를 연구하였다. 본 논문에서는 헤르만 에빙하우스의 망각 곡선 이론을 통해 효율적인 영어 단어 학습방법을 논리적으로 증명하고, 웹사이트를 사용한 라이트너 박스와 망각 곡선의 이론을 적용하여 망각의 주기에 따른 복습의 효과를 적용하여 결과적으로 사용자에게 접근성이 좋은 학습형 플랫폼을 제공하여 시간 대비 학습률이 좋은 시스템을 개발하고자 하였다.

• 베이커리
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• no.11 s.376
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• pp.62-63
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• 1999

• 베이커리
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• no.4 s.393
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• pp.126-129
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• 2001