• 한국철도학회:학술대회논문집
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• 한국철도학회 1998년도 추계학술대회 논문집
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• pp.583-588
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• 1998

Large extrusions of aluminium alloy can be more general and useful as structural material of rolling stocks to reduce weight and labor cost than mild steel and stainless steel. Our company is studying aluminium coach body will be made of 6005A and A5083 alloy. In this paper, at first detailed finite element analysis is carried out to calculate the orthotropic material properties of aluminium extrusions. And then global strength evaluation of coach body is carried out according to UIC 566 OR code.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 춘계학술대회논문집
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• pp.1449-1452
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• 2006

When fluid at high speed flows over an open cavity, large acoustic pressure fields inside the cavity are produced by fluid/structure interactions at the downstream end of the cavity. The inter-coach spacing is one of the most important sources of the aero-acoustic noise of a high-speed train. This noise can usually be heard as low frequency structure-borne noise inside the train. In this study experiments were performed in order to investigate the effects of mud-flap length on the aeroacoustic noise generation inside high-speed trains. Results of the measurement confirmed that the characteristics of the noise generated from the inter-coach spacing are strongly dependent on the size of the gap. Also investigated are the characteristics of the turbulent flow after the inter-coach spacing and consequent generation of the aeroacoustic noise inside the cabin.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2006년도 추계학술대회 논문집
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• pp.43-49
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• 2006

To design railway vehicles to ensure comfortable running, ride comfort of human exposed on vibrating carbody should be considered. Also, to improve ride comfort for passenger coach, many factors should be analysed and evaluated. There are many factors as suspension characteristics of railway vehicle, track characteristics to run etc. In this paper, passenger coach sujected to test on specific routine were evaluated using test results. Test routine were divided by 13 sections to analyse more detail. And the characteristics of every section were analysed distributions of radius curves, tunnel and bridge which could give impact to ride comfort. The evaluation of ride comfort were accomplished by UIC and ISO methods.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2006년도 추계학술대회 논문집
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• pp.1259-1263
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• 2006

The inter-coach spacing is one of the most important sources of the aero-acoustic noise of a high-speed train. When fluid at high speed flows over an open cavity, such as the inter-coach spacing, large acoustic pressure fields inside the cavity are produced by fluid/structure interactions at the downstream end of the cavity. In this study experiments were performed to investigate the characteristics the aero-acoustic noise generation from the inter-coach spacing of a high-speed train. Results of the measurement confirmed that the noise generated from the gap between mud-flaps are strongly dependent on the size of the gap.

• 디지털융복합연구
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• 제19권12호
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• pp.487-494
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• 2021

본 연구는 중학교 축구지도자의 리더십 유형과 운동 몰입 및 팀 분위기의 관계 알아보는 데 그 목적이 있으며 다음과 같은 결과가 나왔다. 첫째, 인구통계학적 특성에 따라 분석한 결과 연령에서는 팀 분위기의 동료 관계 특성에서, 지도자와의 생활기간에 따른 변인으로는 상호적 리더십이 유의한 차이가 있는 것으로 나타났다. 둘째, 중학교 축구지도자의 리더십 유형과 운동 몰입의 관계를 알아본 결과 리더십 유형 중 서번트 리더십은 운동 몰입의 모든 하위요인에, 변혁적 리더십은 행동몰입에 영향을 미치는 것으로 나타났다. 셋째. 중학교 축구지도자의 리더십 유형과 팀 분위기의 관계를 알아본 결과 팀 분위기의 하위요인인 역할특성에는 모든 리더십 유형이, 동료 관계 특성에는 서번트 리더십이, 팀 특성에는 상호적 리더십이 영향을 미치는 것으로 나타났다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.2011-2016
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• 2004

Study of human-robot communication is one of the most important research areas. Among various communication media, any useful law we find in voice communication in human-human interactions, is significant in human-robot interactions too. Control strategy of most of such systems available at present is on/off control. These robots activate a function if particular word or phrase associated with that function can be recognized in the user utterance. Recently, there have been some researches on controlling robots using information rich fuzzy commands such as "go little slowly". However, in those works, although the voice command interpretation has been considered, learning from such commands has not been treated. In this paper, learning from such information rich voice commands for controlling a robot is studied. New concepts of the coach-player model and the sub-coach are proposed and such concepts are also demonstrated for a PA-10 redundant manipulator.

• 한국안전학회지
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• 제30권3호
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• pp.1-6
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• 2015

Self-piercing riveting (SPR) is receiving more recognition as a possible and effective solution for joining automotive body panels and structures, particularly for aluminum parts and dissimilar parts. In this study, static strength and fatigue tests were conducted using coach-peel and cross-tension specimens with Al-5052 plates for evaluation of fatigue strength of the SPR joints. For the static experiment results, the fracture modes are classified into pull-out fracture due to influence of plastic deformation of joining area. During the fatigue tests for the coach-peel and cross-tension specimens with Al-5052, interface failure mode occurred on the top substrate close to the rivet head in the most cycle region. There were relationship between applied load amplitude $P_{amp}$ and life time of cycle N, $P_{amp}=715.5{\times}N^{-0.166}$ and $P_{amp}=1967.3{\times}N^{-0.162}$ were for the coach-peel and cross- tension specimens, respectively. The finite element analysis results for specimens were adopted for the parameters of fatigue lifetime prediction. The relation between SWT fatigue parameter and number of cycles was found to be $SWT=192.8N_f^{-0.44}$.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 추계학술대회 논문집
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• pp.711-716
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• 2011

Today, high-speed trains enjoy wide acceptance as fast, convenient and environment-friendly means of transportation. However, increase in the speed of the train entails a concomitant increase in the aerodynamic noise, adversely affecting the passenger comfort. At the train speed exceeding 300 km/h, the effects of turbulent flows and vortex sheddding are greatly amplified, contributing to a significant increase in the aerodynamic noise. Drawing a biomimetic analogy from low-noise flight of owl, a method to reduce aerodynamic noise at inter-coach space of high-speed trains is investigated. The proposed method attempts to achieve the noise reduction by modifying the turbulent flow and vortex shedding characteristics at the inter-coach space. To determine the aerodynamic noise at various train speeds, wind tunnel testing and numerical CFD (Computational Fluid Dynamics) simulation for the basic inter-coach spacing model are carried out, and their results compared. The simulation and experimental results reveal that there are discrete frequency components associated with turbulent air flow at constant intervals in the frequency domain

• 대한기계학회논문집B
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• 제32권9호
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• pp.645-651
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• 2008

For a high speed train driving at 300 km/h, aero-acoustic noise is a dominant component among various noise sources. The aeroacoustic noise is mainly due to inter-coach spacings because discontinuities in the train surface significantly disturb turbulent flows. This often leads to the uncomfortableness of passengers. Interestingly, the aero-acoustic noise reduces with decreasing the mud-flap spacing of the inter-couch spacing. We perform numerical simulations to investigate flow characteristics around the inter-coach spacing. We model the inter-coach spacing as a simple 2-D cavity with flaps, and calculate the velocity and pressure field using two equation turbulence models, varying the flap spacing. The results show that a wider flap spacing develops a higher inflection point in mean velocity profiles over the cavity. It is likely that large eddies generated near the inflection point persist longer in the downstream since they are less affected by the wall. This probably induces the more aero-acoustic noises. The wider spacing also results in the larger pressure difference between the inside and outside of the cavity. This is also responsible for the increased noise since the large difference would cause a strong flow oscillations in and out of the cavity.

• 한국융합학회논문지
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• 제11권7호
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• pp.329-335
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• 2020

본 연구는 스쿠버다이빙 참여자의 비언어적 커뮤니케이션과 지도자 신뢰 및 참여지속의도 간의 관계를 규명하는데 목적이 있다. 이 연구의 목적 달성을 위해 강원도에 소재한 스쿠버다이빙 리조트 3곳의 이용자와 경기도에 소재한 스쿠버다이빙 풀 2곳의 이용자를 대상으로 편의표본추출법을 통해 최종 유효 표본 총 267부를 선정하였다. 자료처리는 SPSS 18.0을 이용하여 단순회귀분석 및 중다회귀분석을 실시하였으며 다음과 같은 결과를 도출하였다. 첫째, 비언어적 커뮤니케이션의 신체언어와 유사언어는 지도자 신뢰에 유의한 영향을 미치는 것으로 나타났으나 공간행위와 신체외양은 유의미 하지 않았다. 둘째, 지도자 신뢰는 참여지속의도에 유의한 영향을 미치는 것으로 나타났다. 셋째, 비언어적 커뮤니케이션의 신체언어는 참여지속의도에 유의한 영향을 미치는 것으로 나타났다. 그러나 공간행위, 유사언어, 신체외양은 참여지속의도에 유의미하지 않았다.