• Title/Summary/Keyword: 페달

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Biomechanical Differences of Cycle Pedaling according to Uphill Slope (사이클 페달링 시 오르막 경사도에 따른 운동역학적 차이 분석)

  • Do-Hyung Kim;Suk-Hoon Yoon
    • Korean Journal of Applied Biomechanics
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    • v.34 no.3
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    • pp.105-114
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    • 2024
  • Objective: The purpose of this study is to provide quantitative data through biomechanics analysis of lower extremity movements according to uphill slope when pedaling a cycle. The method of the study were as follow. Method: Ten healthy adult males (age: 30.18 ± 4.2 yrs., height: 173.75 ± 2.99 cm, weight: 66.9 ± 2.64 kg), and who have a weekly exercise distance of more than 100 km and participated in amateur competitions with no lower extremity musculoskeletal injury within the past six months participated in this study. The experiment was conducted at three uphill slopes of 8%, 14%, and 20%, and the intensity of the experiment was 5.5 to 6 watts per kg of body weight for each slope for 4 minutes. A 3-Dimensional motion analysis with eight infrared cameras (sampling rate: 200 Hz) and five-channel of EMG (sampling rate: 2,000 Hz) was performed. In this study event 1, 2, 3, and 4 were set at angular position of pedal at 330°, 30°, 150° and 210°, respectively. Also connections of events were set as phases (P1~P4). A one-way ANOVA with repeated measures was conducted to verify the intervention effect and the statistical significance was set at α=.05. Results: As the uphill slope increased, the position of COM moved further back from the center of the cycle. In the knee joint, P1 and P3 showed greater ROM and higher angular velocity as the slope increased, while P2 and P4 showed opposite results. As the slope increased the peak activation timing was found to be faster for the vastus lateralis and biceps femoris, while the peak activation timing for the medial gastrocnemius muscle was delayed. Conclusion: There was a difference in kinematics as the uphill slope increased during cycling, and the difference between 8% and 14% showed a greater change than the difference between 14% and 20%.

Effect of Contruals on Social Action Perception: Modulation of Motor Resonance Effect by Perspectives (사회적 행위 지각에 있어 해석 효과: 관점에 따른 운동공명효과의 조절)

  • Lee, Dong-Hoon;Shin, Cheon-Woo;Shin, Hyun-Jung
    • Korean Journal of Cognitive Science
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    • v.23 no.1
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    • pp.109-132
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    • 2012
  • According to recent embodied cognition approach, understanding of actions is not based on abstract symbolic process but based on mental simulation of sensory-motor information related to those actions. As supporting evidence, motor resonance effect is a facilitation/interference effect of motor response in terms of similarity between observed action and concurrent own action. In the current research, we investigated this effect in the situation to perceive a complex social action perception and how it would be modulated by perspectives of construals of the social action scene. For this purpose, we created three kinds of fighting action scenes of two people in terms of body actions of the subject(ie., hitting, stepping, biting), and described them in two perspectives; active and passive. During the experiment, subjects had to verify the congruency of the picture and the description first, and if they are congruent, they had to do two different actions in terms of color of following cues. In the first experiment, subjects' response time for stepping on a pedal and pressing a button were analyzed for measuring motor resonance effect for the foot movement. In the second experiment, voice response time with a microphone and button pressing time were analyzed for the mouth movement motor resonance effect. Results showed the facilitation of the foot movement(in Exp1), and the mouth movement(in Exp2) only when the action scene was described in active perspective. Our results indicate that the motor resonance effect can be occurred during perception of social actions in the real life situation, but it can be also modulated by the perspective of the mental construal of the action event.

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Exploration of Neurophysiological Mechanisms underlying Action Performance Changes caused by Semantic Congruency between Perceived Action Verbs and Current Actions (지각된 행위동사와 현재 행위의 의미 일치성에 따른 행위 수행 변화의 신경생리학적 기전 탐색)

  • Rha, Younghyoun;Jeong, Myung Yung;Kwak, Jarang;Lee, Donghoon
    • Korean Journal of Cognitive Science
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    • v.27 no.4
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    • pp.573-597
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    • 2016
  • Recent fMRI and EEG research for neural representations of action concepts insist that processing of action concepts evoke the simulation of sensory-motor information. Moreover, there are several behavioral studies showing that understanding of action verbs or sentences describing actions interfere or facilitate current action performance. However, it is unclear that online interaction between processing of action concepts and current action is based on the simulation of sensory-motor information, or other neural mechanisms. The present research aims to explore the underlying neural mechanism that how the perception of action language influence the performance of current action using high-spacial temporal resolution EEG and multiple source analysis techniques. For this, participants were asked to perform a cued-motor reaction task in which button-pressing hand action and pedal-stepping foot action were required according to the color of the cue, and we presented auditorily action verbs describing the responding actions (i.e., /press/, /step/, /stop/) just before the color cue and examined the interaction effect from the semantic congruency between the action verbs and the current action. Behavioral results revealed consistently a facilitatory effect when action verbs and responding actions were semantically congruent in both button-pressing and pedal-stepping actions, and an inhibitory effect when semantically incongruent in the button-pressing action condition. In the results of EEG source waveform analysis, the semantic congruency effects between action verbs and the responding actions were observed in the Wernicke's area during the perception of action verbs, in the anterior cingulate gyrus and the supplementary motor area (SMA) at the time when the motor-cue was presented, and in the SMA and primary motor cortex (M1) during action execution stage. Based on the current findings, we argue that perceived action verbs evoke the facilitation/inhibition effect by influencing the expectation and preparation stage of following actions rather than the directly activating the particular motor cortex. Finally we discussed the implication on the neural representation of action concepts and methodological limitations of the current research.

Strength Design of Lightweight Composite Bicycle Frame (복합재료 라미네이트 경량화 자전거 프레임의 강도 설계)

  • Lee, Jin Ah;Hong, Hyoung Taek;Chun, Heung Jae
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.37 no.2
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    • pp.265-270
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    • 2013
  • Strength design for a lightweight bicycle frame made of carbon/epoxy composite laminates was studied using Tsai-Wu's failure criterion. For the design of bicycle frames, reducing the weight of the frame is of great importance. Furthermore, the frame should satisfy the required strength under specific loading cases. In accordance with the European EN 14764 standard for bicycle frames, three loading cases-pedaling, vertical, and level loadings-were investigated in this study. Because of the anisotropic characteristics of composite materials, it is important to decide the appropriate stacking sequence and the number of layers to be used in the composite bicycle frame. From finite element analysis results, the most suitable stacking sequence of the fiber orientation and the number of layers were determined. The stacking sequences of $[0]_{8n}$, $[90]_{8n}$, $[0/90]_{2ns}$, $[{\pm}45]_{2ns}$, $[0/{\pm}45/90]_{ns}$ (n = 1, 2, 3, 4) were used in the analysis. The results indicated that the $[0/{\pm}45/90]_{3s}$ lay-up model was suitable for a composite bicycle frame. Furthermore, the weakest point and layer were investigated.

의사소통식 영어 발음지도

  • 김정렬
    • Proceedings of the KSPS conference
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    • 1997.07a
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    • pp.45-60
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    • 1997
  • 의사소통식 영어교수법은 Widdowson (1978)이래, 과거 20여 년간의 여러 외국어 교수 방법들을 (침묵식 교수법, Gattegno; 자연적 교수법, Terrell & Krashen; 전신반웅 교수법, Asher; 집단언어 학습법, Curran; 암시적 교수법, Lozanov) 거치면 서, 이들 중에서 의사소통을 중심으로 한 여러 가지 방법을 총괄하여, 명실공히 외국어 교육 방법의 중심으로 그 자리를 갈수록 확고히 잡아가고 있다. 의사소통식 교수법은 우선 언어란 의사소통을 위한 수단이며, 의사소통은 사회 속에서 일어나는 사회 언어적 행위로 본다. 따라서, 외국어 교육의 목적을 무엇보다도 의사소통 기능의 숙달에 두는 것이다. 일반적인 의사소통 상황을 보면 발화내용의 문법적 정확성은 그 상황에 대한 내용의 적절성 여부에 비하면, 부수적인 것이다. 예를 들면, 사과를 하는 의사소통기능을 공부하면서, 사과하는 표현으로 Sorry라는 말을 썼다고 하자. 이때, 영어는 주어 생략 언어가 아니기 때문에, Sorry 대신에 문법적으로 완전한 문장인 I'm sorry 로 표현해야 한다는 문법적인 문제보다는 사과하는 표현이 그 상황에서 적절하게 쓰인 것인지를 묻는 것에 초점을 맞춘 것이 의사소통식 교수 방법이다. 현재, 초등학교 16 종 영어 교과서도 의사소통 기농들을 적절한 상황에 맞춰서 의사소통식 교수 방법의 정신을 비교적 잘 반영하고 있다. 그러나, 발음에서만큼은 아직도 의사소통식 교수방법을 무시하고, 정확한 발음의 명시적인 설명이나, 예시에 그치는 경향이 뚜렷하다. 이러한 경향은 교육부에서 고시한 제6차 교육과정과 이에 따른 해설서에서 되풀이되고 있다. 발음지도에 많은 관심을 기울여 많은 양의 지면을 할애하고 있음에도 불구하고, 전후에 흐르는 의사 소통식 영어교육의 맥을 완전히 끊고, 단지 정확한 발음의 해부학적 예시와 기술에 그 치고 있다 (임영재 외 1995). 이러한 발음기관의 단면도를 이용한 해부학적 발음의 예시는 특정 자음의 정확한 혀의 위치를 알려 줄 수는 있지만, 발음훈련을 대신하지는 못한다. 예를 들어, 자전거를 타고자 하는 사람이 자전거의 페달을 밟았을 때, 그 동력전달 과정을 자세히 소개한 책자를 읽었다고 해서, 자전거를 탈 수 있는 것은 아니다. 역시, 자전거를 타고자 하면, 실제로 타고 넘어지면서 배우게 되는 것이다. 그리고, 발음훈련의 경우 교재의 내용이나 의사소통 기능은 의사소통식으로 가르치면서도 발음만큼은 아직도 원어민의 입모양을 활용한 듣고 따라하기 식의 전통적인 방법의 발음훈련을 계속하고 있다. 이러한 전통적 발음훈련 방법은 구체적으로 다음 장에서 제시되겠지만, 초등학교에서 듣고 따라하기나 듣고 골라내기와 같은 방법으로 발음훈련을 하면, 많은 학생들이 쉽게 지루해 하고, 아마 영어시간 중에서 가장 싫어하는 시간이 발음연습 시간이 될 가능성이 많이 있다. 현재 의사소통식 교수 방법을 모태로 한 교과서에서도 의사소통식 발음지도법을 쓰지 않았다는 것은 새로이 시작하는 초등학교 영어교육에서 아쉬운 점이라 아니할 수 없다. 초등학교 학생들에 대한 발음 지도의 핵심은 그들의 지적, 정서적, 신체적 특징을 잘 고려해야 한다. 초등학교 학생은 지적, 정서적, 신체적으로 성장기에 있어서, 호기심이 많고, 모방성이 강하며, 감수성이 예민하여 마음에 상처를 받기도 쉽다. 그리고, 무엇보다도, 끊임없이 신체적으로 움직이고 싶어한다. 이러한 학생들의 특정 을 반영하여 발음을 지도하는 길은 역시 초등학교 교과서의 다른 영역들처럼, 학생들은 움직이는 활동을 하면서 재미를 느끼고, 교사는 이들 활동을 통해서 교수목표를 성취하는 쪽으로 맞추어야 한다. 본 논문에서는 먼저 발음지도가 필요한 이유와 요인을 살펴본다. 그리고, 전통적인 발음지도 방법을 일별해 보고, 의사소통식 발음지도법을 제시하는 순으로 논의를 전개하기로 한다.

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Comparative Study of Subjective Mental Workload Assessment Techniques for the Evaluation of ITS-oriented Human-Machine Interface Systems (지능형 교통체계 기반 인간-기계 인터페이스 시스템 평가를 위한 정신적부하 측정방법의 비교 연구)

  • Cha, Doo-Won;Park, Peom
    • Journal of Korean Society of Transportation
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    • v.19 no.3
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    • pp.45-58
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    • 2001
  • Subjective mental workload assessment technique becomes a standard human factors and human-machine interface evaluation tool for the evaluation of ITS(Intelligent Transport Systems)-oriented information systems as well as the drivers visual activity analysis, physiological indices(GSR, EEG, ECG, etc.), secondary task performance, reaction time. vehicle control parameters(speed, steering behavior, accelerator control) that are widely applied for transportation and vehicle systems to evaluate the safety, to decide the system or design alternatives, and to establish the design guidelines. This paper reviewed and compared the most globally employed four mental workload assessment techniques that have been designed for the use of various human-machine systems and ITS-oriented in-vehicle information systems. NASA-TLX(National Aeronautics and Space Administration-Task Load Index). SWAT(Subjective Workload Assessment Technique), MCH(Modified Cooper-Harper) scale, and recently developed RNASA-TLX(Revision of NASA-TH) were compared in terms of sensitivity and subjective evaluations to derive the human-machine interface evaluation guidelines for the application of ITS-oriented in-vehicle information systems. Then, experiment results supported that RNASA-TLX is the prospective tool for the mental workload assessment of ITS-oriented in-vehicle information systems.

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The Effects of in Vehicle Watching TV on Driver Behavior (운전 중 TV시청이 운전행동에 미치는 영향)

  • Sin, Yong-Gyun;Im, Pyeong-Nam;Gang, Su-Cheol;Ryu, Jun-Beom
    • Journal of Korean Society of Transportation
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    • v.24 no.3 s.89
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    • pp.103-112
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    • 2006
  • For recent innovation of If technology and the beginning of Digital Multimedia Broadcasting (DMB) service, it has been dramatically increased to setup TV system in a car for watching TV and receiving traffic Information. Watching TV while driving would distract a driver s cognitive and visual attention as eating food, operating the radio, using a cell phone. However, there is paucity of empirical researches and it is uncertain how watching TV in driving impacts on the driver's cognition in the concrete. Therefore, we surveyed domestic drivers on the attitude watching TV while driving as well as conducted experiments through a driving simulator. Especially, we recruited two groups of participants to explore the effects of watching TV on driving behavior. The result proved that the participants who watched TV while their driving had relatively narrower the attention span than the Participants who did not watch TV. Also, those who watched TV drove with less stability and more urgent operations of the brake and accelerator than those who did not watched TV Finally, we discussed limitations and implications of the study.

Analysis of Muscle Activities and Driving Performance for Manipulating Brake and Accelerator Pedal by using Left and Right Hand Control Devices (장애인용 핸드컨트롤을 이용한 가속 및 제동 페달을 동작할 때의 상지 근육 EMG 분석 및 운전 성능 평가)

  • Song, Jeongheon;Kim, Yongchul
    • Journal of Biomedical Engineering Research
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    • v.38 no.2
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    • pp.74-81
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    • 2017
  • The purpose of this study was to investigate the EMG characteristics of driver's upper extremity and driving performance for manipulating brake and accelerator pedal by using left and right hand control devices during simulated driving. The people with disabilities in the lower limb have problems in operation of the motor vehicle because of functional loss for manipulating brake and accelerator pedal. Therefore, if hand control device is used for adaptive driving controls in people with lower limb impairments, the disabled people can improve their quality of life by driving a motor vehicle. Six subjects were participated in this study to evaluate driving performance and muscle activities for operating brake and accelerator pedal by using two different hand controls (steering column mounted hand control and floor mounted hand control) in driving simulator. We measured EMG activities of six muscles (posterior deltoid, middle deltoid, triceps, biceps, flexor carpi radialis, and extensor carpi radialis) during pushing and pulling movement with different hand controls for acceleration and braking. STISim Drive 3 software was used for the performance test of different hand control devices in straight lane course for time to reach target speed and brake reaction time. While pulling the hand control lever toward the driver, normalized EMG activities of middle deltoid, triceps and flexor carpi radialis in subjects with disabilities were significantly increased (p < 0.05) compared to the normal subjects. It was also found that muscle responses of posterior deltoid were significantly increased (p < 0.05) when using the right hand control than left hand control. While pushing the hand control lever forward away from the driver, normalized EMG activities of posterior deltoid, middle deltoid and extensor carpi radialis in subjects with disability were significantly increased (p < 0.05) compared to the normal subjects. It was shown that muscle responses of middle deltoid, biceps and extensor carpi radialis were significantly increased when using the right hand control than left hand control. Brake reaction time and time to reach target speed in subjects with disability was increased by 12% and 11.3% on average compared to normal subjects. The subjects with physical disabilities showed a tendency to relatively slow acceleration at the straight lane course.

A Study on the Cause of Noise and Vibration of an Elevator (엘리베이터 소음 및 진동의 원인에 관한 연구)

  • 이성춘;김준호;김두훈
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 1994.04a
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    • pp.94-99
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    • 1994
  • 최근 인구의 과밀화와 이에 따른 지가의 상승 등으로 대표적인 주거용 빌딩인 아파트의 고층화가 급속하게 진행되고 있고 아파트에 설치되는 엘리베이터도 점차 대형화, 고속화 되고 있다. 실례로 15층 아파트의 경우 11인승, 60m/min의 엘리베이터가 일반적으로 사용되는 반면, 20층 아파트의 경우 17인승, 90m/min이 주로 사용된다. 이와 같이 엘리베이터의 용량과 운행 속도가 증가함에 따라 필연적으로 소음 및 진동 문제가 발생하게 된다. 특히 아파트의 경우 침실, 공부방 등 고도의 정숙을 요하는 생활 공간이 많고, 내부 공간의 활용도를 높이기 위하여 이들 방들이 엘리베이터 기계실 또는 운행 통로와 직접 접하여 있는 경우도 있어 이 경우 소음, 진동 문제는 아주 심각한 문제로 대두된다. 본 연구소가 측정한 방에 의하면 S신도시 L아파트의 경우 아파트 최상층 방에서 실내 소음도가 46dB(A), 벽의 진동가속도가 3.4mm/s$^{2}$(RMS)으로 나타났다. 진동의 경우 생활에 직접적인 악영향을 미칠 수준은 아니지만 소음의 경우 ASHRAE 권장 주택소음 기준치가 35dB(A) 이하임ㅇㄹ 감안하면 주거에 곤란한 수준이다. 수년전, 고층 아파트가 보급될 초기에는 아파트에 엘리베이터가 설치되어있다는 그 자체만으로 충분한 장점이 되어 다소음 소음, 진동문제는 큰 불만거리가 되지 않았지만 엘리베이터가 보편화된 지금에는 엘리베이터의 편리성만으로는 점점더 크게 요구되는 정숙성이 보상되지 않는다. 따라서 전반적인 아파트의 소음, 진동 문제에 큰 비중을 차지하는 엘리베이터에 의한 소음, 진동에 관하여 체계적인 연구가 필요하다. 이에 본고에서는 엘리베이터에 의한 아파트의 소음 및 진동에 관하여 그 현황, 원인 그리고 대책에 관한여 논하고자 한다.감 방법을 연구하였고, T.Sakai는 5자유도 모델을 이용하여 엔진 공회전시 발생하는 치타음에 대해 이론과 실험을 통해 해석하고, 엔진 회전수 변동, 클러치 특성, 변속기의 드래그(drag) 토크의 영향과 치타음 저감을 위한 개선된 클러치 특성을 제시하였다. 이 외에도 Thomas C.T.와 E.P.Petkus는 특정 차량에 대한 동력전달계의 비틀림 진동 현상에 대해 연구하였다. 이러한 연구들로 볼 때, 자동차 동력전달계에서 발생하는 진동은 이론과 실험을 통해 그 해석이 가능하며 설계에 매우 유용하게 이용되고 있음을 알 수 있다. 따라서, 본 연구는 4 실린더 4 싸이클 1.5 L 엔진을 장착한 경승용차의 실차 주행실험을 통해 가속 페달의 급조작에 따른 차체의 종진동 현상을 측정하고, 엔진-변속기-타이어-차체의 반환정계 4자유도 진동모델로 시뮬레이션을 수행하여 실차 주행실험의 결과치와 비교, 분석한 후 클러치 비틀림 특성을 비롯한 자동차 동력전달계의 각 설계인자들이 차체의 종진동에 어떠한 영향을 미치는가를 해석하고자 한다.be presented.LIFO, 우선 순위 방식등을 선택할 수 있도록 확장하였다. SIMPLE는 자료구조 및 프로그램이 공개되어 있으므로 프로그래머가 원하는 기능을 쉽게 추가할 수 있는 장점도 있다. 아울러 SMPLE에서 새로이 추가된 자료구조와 함수 및 설비제어 방식등을 활용하여 실제 중형급 시스템에 대한 시뮬레이션 구현과 시스템 분석의 예를 보인다._3$", chain segment, with the activation energy of carriers from the shallow trap with 0.4[eV], in he amorphous regions.의 증발산율은 우기의 기상자료를 이용하여 구한 결과 0.05 - 0.1

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The effect of operating telematics device in vehicle on driver behaviors (운전중 텔레매틱스 장치 사용이 운전행동에 미치는 영향)

  • Sihn, Yong-Kyun;Ryu, Jun-Beom
    • Journal of Korean Society of Transportation
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    • v.26 no.6
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    • pp.39-47
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    • 2008
  • With dramatic development of IT technology and start of DMB service, installing the DMB equipment in a vehicle for watching TV programs and literal or pictorial traffic information are increasing. Watching the DMB during driving the vehicle could cause visual and cognitive distraction to drivers as much as eating food, operating radio and using mobile phone. However, there is not much empirical research for this topic and no research examined the effect of watching the DMB on driving behaviors in Korea. So, the present study examined the effect of watching the DMB on the driving behaviors with car simulator experiment. Within subject design was used in the study. That is, all subjects drove the vehicle both in the watching DMB condition and the non-watching DMB condition. The results indicated that subjects in the watching DMB condition took longer time to arrive at the destination and operated accelerator and brake pedal rapidly than subjects in the non-watching DMB condition. That is, their overall driving stability was lower than non-watching subjects'. Additionally, we examined the difference among the DMB control conditions (i.e., keypad condition, touch-pad condition and remote controller condition) in the driving behaviors. Finally, we discussed the limitations and the implications of the present study.