• 한국자동차공학회논문집
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• 제10권4호
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• pp.206-215
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• 2002

It is to be classified into friendly environment and safety problems, as a main technology development of the recent automotive industry. As these tendency, lots of automobile companies focus on a reduction of fuel expenses and strengthen of crash safety using high strength steel. In this study advanced technologies such as tailored blanks, aluminum extrusion and high strength steel forming applied to bumper beam will be described. As a result of impact analysis and an actual impact test, in terms of beam performance and a possibility fur the mass production will be discussed.

• Steel and Composite Structures
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• 제4권1호
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• pp.49-75
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• 2004

The paper derives, validates and illustrates the application of GBT-based formulae to estimate distortional critical lengths and bifurcation stress resultants in cold-formed steel rack-section columns, beams and beam-columns with arbitrarily inclined mid-stiffeners and four support conditions. After a brief review of the Generalised Beam Theory (GBT) basics, the main concepts and procedures employed to obtain the formulae are addressed. Then, the GBT-based estimates are compared with exact results and, when possible, also with values yielded by formulae due to Lau and Hancock, Hancock and Teng et al. A few remarks on novel aspects of the rack-section beam-column distortional buckling behaviour, unveiled by the GBT-based approach, are also included.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2010년도 춘계 학술대회 제22권1호
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• pp.121-122
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• 2010

본 연구는 내진설계에서 중요한 부분인 철근콘크리트 보-기둥 접합부를 관찰한다. 접합부에 인접한 보에서 발생한 소성힌지로 인한 부착 감소로 보 주인장철근 미끄러짐에 따른 접합부 내력 및 연성 변화를 보 주인장철근량을 변수로 하여 평가한다.

• 제어로봇시스템학회논문지
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• 제10권1호
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• pp.30-41
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• 2004

This paper is concerned with the active vibration control of flexible cantilever beam system using electromagnetic farce actuator. The main objective of this paper is to propose the control algorithms and to implement the experimental setups for active vibration control. Dynamic equations of the electromagnetic actuator and the beam are combined to find the transfer function from the electromagnetic actuator to the laser sensor. The final transfer function is determined by considering only the first and second modes, and experiments confirm that this model works well. Several control algorithms are proposed and implemented on the experimental setups to show their efficacy. These include a PID control design, an optimal H$_2$ control design, and a fuzzy PID control design. Effectiveness and performance of the designed controller were verified by both simulation and experiment results.

• 대한기계학회논문집A
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• 제30권3호
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• pp.279-286
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• 2006

The main purpose of this paper is to apply differential transformation method(DTM) and generalized differential quadrature method(GDQM) to vibration analysis of Euler-Bernoulli beam with open cracks on elastic foundation. In this paper the concepts of DTM and GDQM were briefly introduced. The governing equation of motion of the beam with open cracks on elastic foundation is derived. The cracks are modeled by massless substitute spring. The effects of the crack location, size and the foundation constants, on the natural frequencies of the beam, are investigated. Numerical calculations are carried out and compared with previous published results.

• 한국구조물진단유지관리공학회 논문집
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• 제3권4호
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• pp.145-153
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• 1999

The major objective of this study is to investigate experimentally the shear strengthening effect of carbon fiber sheets upon reinforced concrete deep beam and shear failure behavior variation of reinforced concrete deep beam strengthened by carbon fiber sheets. Tests are carried out with 6 specimens were shear failure at first loading tests, and with parameters including the types of shear strengthening of carbon fiber sheets (I type, S type, U type), and plies of sheets (2 ply and 1 ply). From the results of test, analyzed load-deflection of midspan, strain variation of main bars and transverse reinforcement, maximum load capacity of strengthened specimens, and compared with the previous test results.

• 한국전자파학회논문지
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• 제10권5호
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• pp.738-746
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• 1999

본 논문은 10GHz 에서 동작하는 마이크로스트립 $18\times2$ 이중 빔 배열 안테나를 설계 하였다. 단일 복사 소자는 개구면 결합형 패치를 사용하였으며, 이를 전송선 모델을 이용하여 해석 하였다. 급전선은 Side Lobe Level(SLL)를 줄이기 위해 tapered 직-병렬 구조를 사용하였다. 또한 45도에서 이중 빔을 갖게 하기 위해 소자간에 180도 위상차를 주었다. 그 결과 SLL은 25dB를 가지며, $\pm44.5$도에서 두개의 빔을 갖게 되며 8도의 좁은 빔폭을 갖는다.

• 한국음향학회지
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• 제15권1호
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• pp.40-45
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• 1996

이 논문에서는 최적의 빔패턴을 얻기 위한 비선형 최적 설계 기법을 제시하였다. 제시된 방법을 사용하여 진동체 사이의 자기 및 상호 방사 임피던스를 고려하여 최대 허용 부엽준위가 주어진 경우 빔폭이 최소화된 빔 패턴을 설계할 수 있다. 그리고 37개의 진동체가 X, Y 및 $45^{circ}$축에 대칭으로 배열된 평면 배열에 대해 제안된 기법을 적용한 결과 빔폭은 변화없이 상당히 낮은 부엽 준위를 얻었다.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2002년도 봄 학술발표회 논문집
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• pp.43-50
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• 2002

Main goal of this study is to develop MATLAB programming for exact analysis of distortional deformation of the straight box girder. For this purpose, a theory for distortional deformation theory is firstly summarized and then a BEF (Beam on Elastic Foundation) theory is presented using analogy of the corresponding variables. Finally, the governing equation of the beam-column element on elastic foundation is derived. An element stiffness matrix of the beam element is established via a generalized linear eigenvalue problem. In order to verify the efficiency and accuracy of the element using exact dynamic stiffness matrix, buckling loads for the continuous beam structures with elastic foundation and distortional deformations of box girders are calculated.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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• pp.113-116
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• 2004

No specific guidelines are for computing the shear strength of steel coupling beam connections embedded in the reinforced concrete shear wall. In this paper, a theoretical study of the strength of hybrid coupled shear wall connections is achieved. The bearing stress at failure in the concrete below the steel coupling beam section is related to the concrete compressive strength and the ratio of the width of the steel coupling beam section to the thickness of the hybrid coupled shear wall. To revise factor affecting shear transfer strength across connections between coupled shear walls and steel coupling beam, experimental studies are achieved. The main test variables were auxiliary details of stud bolts. In this studies, these proposed equations are shown to be in good agreement with the test results reported in the paper and with other test data in the literature.