• 산업기술연구
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• 제15권
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• pp.169-174
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• 1995

A method of calculating the natural frequency corresponding to the first mode of vibration of beams and tower structures, with irregular cross-sections and with arbitrary boundary conditions was developed and reported by D. H. Kim in 1974. IN this paper, the result of application of this method to the laminated plates with axial forces and with attached point mass/masses is presented. Both $N_x$ and $N_y$ forces are considered. The solution for the laminated plates with arbitrary boundary conditions and irregular section can be obtained by simply obtaining the deflection influence coefficients by any method. The effect of neglecting the mass of the plates on the natural frequency, as the ratio of the point mass/masses to the plate mass increases, is thoroughly studied. The influence of $N_x$ and $N_y$ is also carefully investigated.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.1021-1026
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• 2003

The problem of predicting the fracture strength behavior in orthotropic plate with a crack inclined with respect to the principal material axes is analyzed. Both the load to cause fracture and the crack direction of crack growth arc of interest. The theoretical results based on the normal stress ration theory show significant effects of biaxial loading and the fiber orientation on the crack growth angle and the critical stress. The additional term in the asymptotic expansion of the crack tip stress field appears to provide more accurate critical stress prediction.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 합동 추계학술대회 논문집 정보 및 제어부문
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• pp.228-232
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• 2002

This paper is reporting the whole process of developing a weight measuring scaler of truck and trailer system for static and dynamic condition. The sensors attached on the top of springs each wheels. Acquisition and data processing performs accurate data extraction from noise environment, filtering and estimation. Weight information was highly distorted with noise and perturbation. Hence the perturbation was classified several categories and evaluated for accurate signal extract. The final products supply accurate and easy readable data of load weight for truck. It supplies total weight as well as loading condition of each axle. It is expected that it give the information to the truck operator of proper amount loading and safe condition to drive with it.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2011년도 정기 학술대회
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• pp.148-151
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• 2011

현재 방폭설계 관련 설계지침은 기둥제거시나리오를 이용한 대체하중경로법을 주로 적용하고 있지만, 실제로 폭발이 발생하였을 때 기둥의 완전한 파괴가 일어나지 않을 경우 이 방식을 적용하는 것은 적합하지 않다. 따라서 본 논문에서는 비선형 동적 해석 프로그램인 AUTODYN을 이용해 편심하중을 받는 철근 콘크리트 기둥의 잔존 폭발 저항 성능을 평가하는 방식을 제안하였다. 해석결과를 비교해보면 TNT양과 축하중이 클수록 철근콘크리트 기둥의 잔존 폭발 저항 성능이 감소되었다. 이것은 폭발이 발생하기전의 기둥의 편심하중에 의한 응력상태에 따라 폭발 저항 성능이 달라짐을 알 수 있다.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2005년도 춘계학술대회
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• pp.51-57
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• 2005

There are very large differences on the standards of gross weight and single axle weight for commercial motor vehicles between international and Korean standards. Short Wheelbase Truck are produced and run only in Korea. It has very serious effects on the durabilities of bridges and roads and makes logistic competitive power fall back and overconsuming energy. This paper deals with a comparative study of the international standards with Korean, grasps the drawbacks and makes up the suggestions to strengthen the logistic competitive power of Korea and reduce the maintenance cost for the roads and the consumption of energy.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.906-915
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• 2004

Derivation procedures of exact dynamic stiffness matrices of thin-walled curved beams subjected to axial forces are rigorously presented for the spatial free vibration analysis. An exact dynamic stiffness matrix is established from governing equations for a uniform curved beam element with nonsymmetric thin-walled cross section. Firstly this numerical technique is accomplished via a generalized linear eigenvalue problem by introducing 14 displacement parameters and a system of linear algebraic equations with complex matrices. Thus, displacement functions of dispalcement parameters are exactly derived and finally exact stiffness matrices are determined using clement force-displacement relationships. The natural frequencies of the nonsymmetric thin-walled curved beam are evaluated and compared with analytical solutions or results by ABAQUS's shell elements in order to demonstrate the validity of this study.

• 한국공간구조학회논문집
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• 제13권4호
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• pp.67-74
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• 2013

The Age-adjusted effective Modulus Method(AEMM) is one of the methods adopted for the construction stage analysis of concrete structures. The AEMM uses the aging factor to consider the effects of the varying concrete stress. In the aspects of computation time and the accuracy of the results, the AEMM is considered as one of most appropriate methods for construction stage analysis of tall building structures. Previous researches proposed appropriate values of the aging factor in the forms of graphs or using very simple equations. In this paper, an equation for estimating the aging factor as a function of rebar ratio in the section, compressive strength of concrete, notional member dimension, and age of concrete at the load application. The validity of aging factor proposed in this paper were examined by the comparison with the results of step-by step method.

• 한국지반공학회논문집
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• 제17권2호
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• pp.103-111
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• 2001

지반네일 보강방법은 이론적 뒷받침과 함께 경험적인 작업을 기초로 발전되어 왔으며, 연구 결과를 바탕으로 현장적용이 활발하게 이루어지고 있다. 본 연구에서는 소일 네일로 보강된 토체의 안정성에 중요한 요소인 소일네일의 인발저항력을 높이기 위하여 네일의 끝 부분에 앵커와 같은 구근이 형성된 네일로 보강된 토체의 파괴거동을 이해하기 위하여 비교적 큰 규모의 실험을 실시하였다. 토체의 변위, 네일의 축변형률, 네일의 축하중, 토체내부의 토압 등에 관한 자료를 얻었으며 이러한 자료들을 분석하였다. 또한 같은 조건에서 일반적인 형태의 네일로 실험된 결과와 비교분석을 실시하였다.

• 대한기계학회논문집A
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• 제31권2호
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• pp.231-236
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• 2007

This paper presents the effect of the center of the series on convergence in solving vibration problems by Differential Transformation Method(DTM) to the transverse vibration of the Euler-Bernoulli beam under varying axial force. The governing differential equation of the transverse vibration of the Euler-Bernoulli beam under varying axial force is derived. The concepts of DTM were briefly introduced. Numerical calculations are carried out and compared with previously published results. The effect of the center of the series on convergence in solving the problem by DTM is discussed.

• 대한안전경영과학회지
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• 제7권3호
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• pp.37-46
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• 2005

There are very large differences on the standards of gross weight and single axle weight for commercial motor vehicles between international and Korean standards. Short Wheelbase Truck are produced and run only in Korea. It has very serious effects on the durabilities of bridges and roads and makes logistic competitive power fall back and overconsuming energy. This paper deals with a comparative study of the international standards with Korean, grasps the drawbacks and makes up the suggestions to strengthen the logistic competitive power of Korea and reduce the maintenance cost for the roads and the consumption of energy.