• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.1
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• pp.445-453
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• 2013

This paper was calculated the earthquake load using ELFP(Equivalent Lateral Force Procedure) and RSA(Response Spectrum Analysis) for PSC Box Girder representative bridges by the Phase of KTX designed by ELFP and verified the difference of these analyses. It have been modeled 3 dimensional FE model of 5 bridges using a commercial FEM program for the comparison of these analyses using a commercial FEM program and were compared the earthquake load. It has been to confirm the increase of the difference ELFP of RSA calculated to seismic ground acceleration according to the ground condition and natural period. It is mean that the necessity of seismic reinforcement due to the application of a larger of earthquake load than designed earthquake load form the seismic performance evaluation result according to the difference of calculated earthquake loads.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2009.11a
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• pp.198-201
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• 2009

본 연구는 미생물색소로 염색한 소재의 색채감성을 평가하여 색채감성에 영향을 미치는 색채감각과 물리적 색채특성을 규명하고자 한 것이다. 미생물 Zooshikella rubidus 가 생산하는 색소를 추출하여 면, 견, 모, 나일론 직물에 염색한 소재에 대하여 20 대 대학생 남녀 40 명을 대상으로 의미미분법에 의하여 색채감성을 평가시켰다. 색채감성용어에 대한 요인분석결과, 명랑성, 품위성, 매력성, 편안성등 4 개 요인이 도출되었다. 명랑성 요인은 L*, a*, C*, 맑다, 가볍다, 부드럽다, 밝다와 정적 상관을, b*, 강하다, 깊다, 딱딱하다와 부적상관을 보였으며, 품위성 요인은 b*, 따뜻하다와 정적 상관을, a*, C*, 가볍다, 강하다와 부적 상관을 보였다. 또한 매력성 요인은 a*, C*, 맑다, 밝다와 정적 상관을 보였으며, 편안성은 b*, h, 따뜻하다와 정적 상관을, a*, C*, 강하다와 부적 상관을 보였다. 한편, 미생물색소로 염색한 소재에 대한 색채감성 평가는 성에 따른 유의한 차이가 없었으나, 선호도는 성에 따른 유의한 차이가 있었다.

• Korean Journal of Materials Research
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• v.8 no.6
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• pp.565-570
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• 1998

SiCp/6061AI 복합재료의 파괴인성을 평가하기 위하여 정적파괴인성에 대해서는 복수시험편법을, 동적파괴인성시험에 대해서는 stop block법을 실시하였다. 주균열은 예비균열의 선단에서 시험편두께방향 전역에 걸쳐서 일시에 발생하는 것이 아니고, 균열발생의 초기단계에서 국부적으로 형성된 균열이 시험편두께방향으로의 균열의 확장을 완료한 후 주균열로 이행해 간다. 정적 및 동적시험에서 컴플라이언스변화율법에 의해 검출된 균열발생점은 균열확장의 완료점과 거의 일치하고 있기 때문에 본 재료의 파괴인성 결정에 유효하다. 본 재료에서 동적파괴인성치는 정적파괴인성치보다 크게 나타났다. 이것은 동적충격시 입자파괴에 의한 에너지의 흡수.분산효과와 균열진전경로의 큰 편향에 기인한다고 생각된다.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.36 no.2
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• pp.156-162
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• 2008

The static aeroelastic analysis of composite hingeless rotor blades in hover was performed using free-wake method. Large deflection beam theory was applied to analyze blade motions as a one-dimension beam. Anisotropic beam theory was applied to perform a cross-sectional analysis for composite rotor blades. Aerodynamic loads were calculated through a three-dimensional aerodynamic model which is based on the unsteady vortex lattice method. The wake geometry in hover was described using a time-marching free-wake method. Numerical results of the steady-state deflections for the composite hingeless rotor blades were presented and compared with those results based on two-dimensional quasi-steady strip theory and prescribed wake method. It was shown that wakes affect the steady-state deflections.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.3A
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• pp.497-512
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• 2006

In this paper, a simple but effective analysis procedure to estimate seismic capacities of multi-span continuous bridge structures is proposed on the basis of modal pushover analysis considering all the dynamic modes of structure. Unlike previous studies, the proposed method eliminates the coupling effects induced from the direct application of modal decomposition by introducing an identical stiffness ratio and an approximate elastic deformed shape. Moreover, in addition to these two introductions, the use of an appropriate distributed load {P} makes it possible to predict the dynamic responses for all kinds of bridge structures through a simpler analysis procedure. Finally, in order to establish the validity and applicability of the proposed method, correlation studies between rigorous nonlinear time history analysis and the proposed method are conducted for multi-span continuous bridges.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1990.06a
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• pp.389-392
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• 1990

• Journal of the Korean Chemical Society
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• v.47 no.6
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• pp.578-584
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• 2003

Polychlorinated biphenyls (PCBs) known as environmental contaminants in soil were analyzed by the soil pollution standard process test and the static supercritical $CO_2$ extraction mode. It was shown that the percent average recoveries of PCBs by the soil pollution standard process test were ranged in 25-35% and the corresponding standard deviations were above 10%. In contrast, the percent average recoveries of PCBs by the static supercritical $CO_2$ extraction mode were 2-2.5 times higher and standard deviations were within 7%. These results indicate that static supercritical $CO_2$ extraction mode may be a useful alternative to sample pretreatment certified by the soil pollution standard process test. The increasing supercritical $CO_2$ pressure from 1130 psi to 1996 psi at $40^{\circ}C$ enhanced the recovery of all PCB congeners from soil. However, at same Tc and Pc, the equilibrium time (5 versus 60 minutes) had no effect on the recovery of each PCB congener. Finally, similar PCB recoveries were obtained under the same extraction condition, regardless of the molecular weight and structure (coplanar versus non-coplanar) of PCB congeners.

• Journal of the Korean GEO-environmental Society
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• v.10 no.1
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• pp.49-54
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• 2009

The seismic slope stability is most often evaluated by the pseudo-static limit analysis, in which the earthquake loading is simplified as static inertial loads acting in horizontal and/or vertical directions. The transient loading is represented by constant acceleration via the pseudostatic coefficients. The result of a pseudostatic analysis is governed by the selection of the value of the pseudostatic coefficient. However, selection of the value is very difficult and often done in an ad hoc manner without a sound physical reasoning. In addition, the maximum acceleration is commonly estimated from the design guideline, which cannot accurately estimate the dynamic response of a slope. There is a need to perform a 2D dynamic analysis to properly define the dynamic response characteristics. This paper develops a new hybrid pseudostatic method that links the modified one-dimensional seismic site response analysis and the pseudostatic algorithm. The modified site response analysis adjusts the density of the layers to simulate the change in mass and weight of the layers of the slope with depth. Multiple analyses were performed at various locations within the slope to estimate the change in seismic response of the slope. The calculated peak acceleration profiles with depth from the developed procedure were compared to those by the two-dimensional analyses. Comparisons show that the two methods result in remarkable match. The calculated profiles are used to perform pseudostatic analysis. The results show that use of peak or a fraction of acceleration at the surface can seriously underestimate or overestimate the factor of safety, and that the proposed procedure significantly enhances the reliability of a standard procedure.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.4
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• pp.239-250
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• 1993

The dynamic resilient modulus tests to determine the $M_R$ of the soils require expensive equipments and well trained personnels to obtain reliable test results. These problems inherent in the dynamic resilient modulus testing have been realized as major negative factors to hinder the $M_R$ test from being practically implemented as a routine test. In this regard. it is highly desirable to develop a simpler alternative testing method incorporating inexpensive equipments and easy-to-perform testing procedures. Developed in this study is an alternative $M_R$ test method based on statically repeated loading scheme utilizing the standard static triaxial test equipments. Applicability and limitations of the developed static $M_R$ testing method are investigated for typical subgrade soils in Korea.

• Journal of Navigation and Port Research
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• v.27 no.5
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• pp.519-526
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• 2003

For preliminary structural analysis of superstructures on very large floating structures(VLFS), superstructures are analyzed considering elastic deformations of barge type lower-structures subjected to wave loads. In this case, to consider the effect of wave loads on the superstructure, initial displacements at the support points of superstructures are evaluated as input data for the analysis. However, the evaluation and application of displacement loads are tedious and very time-consuming processes. Therefore, this paper proposes a simplified static analysis method to analyze the structural behaviors of superstructures on very large floating structures subjected to wave loads. In this study, the member forces due to the variation of beam span and the amplitude and period of wave load are analyzed by using an example 4 span -3 story structure and the amplification factors for beam moments are represented by the specific regression equation.