• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1993년도 가을 학술발표회논문집
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• pp.199-204
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• 1993

Noise and vibration induced by subway operation are one of the major factor that annoying residents living near the. railway. In general, lateral vibration was the major concern when we are considering vibration of the building. Since the energy due to earthquake is enormous it affects wide area. However, the vertical vibration became a major concern in considering the vibration induced by subway because relatively smaller energy affects only nearby areas than that of earthquake. Analysis model of the structure for the vertical vibration should consider the effect of beam vibration. Thus, the model of the structure for the lateral vibration can not be applied. Appropriate analysis model which can consider the inertia force of the beam is necessary when analyzing a structure for the vertical vibration. Modeling technique for the vertical vibration analysis of structures has been studied on this paper. It is recommeneded to use 2 or more elements for columns and to use 3 or more elements for beams when analyzing structures for vertical vibration induced by subway.

• 한국안전학회지
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• 제19권3호
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• pp.108-117
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• 2004

Dynamic analysis method is Presented for analyzing rectangular liquid storage structures excited by horizontal and vertical ground motions. The irrotational motion of invicid and incompressible ideal fluid in rigid rectangular liquid storage structures subjected to horizontal and vertical ground motions and the motion of fluid induced by structural deformation are expressed by analytic solutions. Analysis methods are obtained by applying analytic solutions of the fluid motion to finite element equation of the structural motion. The fluid-structure interaction effect is reflected into the coupled equation as added fluid mass matrix. The free surface sloshing motion, hydrodynamic pressure acting on the wall and structural behavior due to horizontal and vertical ground motions are obtained by the presented method.

• 산업기술연구
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• 제29권A호
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• pp.127-134
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• 2009

In this paper, an numerical approach is performed to investigate the effects of smear zone, occurred by penetrating vertical drains, on consolidation behavior of soft clay deposits. Such a numerical analysis is applied to the field condition to confirm its applicability. Parametric numerical analyses is carried out to study influencing factors such as permeability in smear zone, boundary of smear zone and discharge capacity of vertical drains on the consolidation of soil. As results of analyses, for the given conditions of soil, degree of consolidation is getting faster with increase of permeability of vertical drain. Degree of consolidation is delayed with decrease of permeability of smear zone. As the ratio of drain width to smear zone increases, the degree of consolidation decreases. Proposed values of influencing factors by previous researchers is found to be reliable from results of numerical analyses with Cam-clay model.

• 한국기계가공학회지
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• 제12권5호
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• pp.50-56
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• 2013

Machine tools are the cores of industrial development in recent period. It is difficult to develop a system which can do cutting and grinding process in the one system. Hybrid Vertical Grinding System is capable of processing in a single apparatus cutting or grinding. The modal analysis and structural analysis for the development of Hybrid Vertical Grinding System is the first time of domestic work. In this study, Hybrid Vertical Grinding System bed was designed and analyzed by using SS401 and FC300 as materials. And by using Finite Element Methods, the design and material of the bed was analysed. Finally, we can make a better choice of structure and material of the bed by comparing the analysis results.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 봄 학술발표회 논문집
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• pp.512-519
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• 2000

The discharge capacity of vertical drains installed in the field is reduced with time elapsed after installation due to deformation of drains and clogging effect. Discharge capacity of two types of vertical drains was analysed about three years after installation in the subsoil. Discharge capacity of two types of vertical drains were measured by small, middle, and large scale test apparatus. The results indicate that the discharge capacity of vertical drains after three years operation dramatically decreased compare to the initial discharge capacity.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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• pp.70-73
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• 2006

Recently, several researches have been performed on the prediction of vertical vibration on structures by using an analytical method. However, these studies have been focused on mainly the vibration analysis through analytical modeling of structures. This study aims to investigate the characteristics of vertical vibration transfer in terms of the directions of transfer(upward transfer and downward transfer) on the shear wall building structures due to heel-drop impact forces. In order to examine the characteristics of vertical vibration transfer, the mode analysis and the impact experiment were conducted several times on two shear wall building structures. The results of this study suggest that the characteristics of vertical vibration transfer are similar in terms of the directions of transfer.

• 통합자연과학논문집
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• 제8권3호
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• pp.221-232
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• 2015

In this study, the vertical characteristics of wind were analyzed using the horizontal wind, vertical wind, and vertical wind shear, which are generated from a wind profiler during concentrated heavy rain, and the quantitative characteristics of concentrated heavy rain were analyzed using CAPE, SWEAT, and SRH, among the stability indexes. The analysis of the horizontal wind showed that 9 cases out of 10 had a low level jet of 25 kts at altitudes lower than 1.5 km, and that the precipitation varied according to the altitude and distribution of the low-level jet. The analysis of the vertical wind showed that it ascended up to about 3 km before precipitation. The analysis of the vertical wind shear showed that it increased up to a 1 km altitude before precipitation and had a strong value near 3 km during heavy rains. In the stability index analysis, CAPE, which represents thermal buoyancy, and SRH, which represents dynamic vorticity, were used for the interpretation of the period of heavy rain. As SWEAT contains dynamic upper level wind and thermal energy, it had a high correlation coefficient with concentrated-heavy-rain analysis. Through the case studies conducted on August 12-13, 2012, it was confirmed that the interpretation of the prediction of the period of heavy rain was possible when using the intensive observation data from a wind profiler and the stability index.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.58-63
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• 2010

HEMU-400X train have been developed and will be operated over 350km/h. In this paper, the influence of vertical alignment on running behavior and safety for HEMU-400X train was instigated by numerical analysis. The wavelength and amplitude of vertical alignment were considered in scenario of this numerical analysis. This research is based on just numerical analysis and the final result which include measurement will be published in the future.

• 한국결정성장학회지
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• 제25권6호
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• pp.231-238
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• 2015

사파이어 단결정은 GaN계 화합물 증착이 용이하여 고휘도 LED(Light Emitting Diode), 고출력 레이저 산업 등에서 크게 각광받고 있다. 다양한 사파이어 단결정 제조공법 중 vertical Bridgman 공법은 고품질의 사파이어를 c-축 방향으로 성장시킬 수 있는 공법이며 상업적으로 적용이 검토되고 있다. 본 연구에서는 2인치 사파이어 성장 vertical Bridgman 공정에서 성장시 온도구배에 의해 발생하는 열응력을 유한요소 모델을 통해 분석하였다. 이를 통해 성장시 수직, 수평방향으로의 온도구배가 사파이어 결정의 열응력과 결함발생에 미치는 영향을 검토하였다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집 특별세미나,특별/일반세션
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• pp.359-366
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• 2009

This paper aims for analyzing the vibration serviceability of train by simply expressing its vertical vibration when it passes a railway bridge. For this purpose, bridge-train transfer function was derived and bridge-train interaction analysis was performed by using the derived function. The bridge-train transfer function was developed with the assumption that train is a single mass-spring system, and bridge-train interaction analysis was performed on simple beams of KTX passenger car. The vertical acceleration signals of passenger cars obtained from bridge-train interaction analysis were compared with them of cars obtained from the bridge-train transfer function. As a result, it could be estimated to express the vertical vibration inside the passenger car required for vibration serviceability evaluation by using the vertical vibration of bridges obtained from moving load analysis. Therefore, it may be possible to evaluate the vibration serviceability of railway bridges considering bridge-train interaction effect.