자동차 페달 반복 사용 시 보조 발판이 하지근육 활동과 피로에 미치는 영향

김정룡,서경배,Kim, Jung-Yong,Seo, Kyung-Bae 대한인간공학회 2005 大韓人間工學會誌 Vol.24 No.4

This study examined the effect of ergonomic heel rest that was designed for drivers who have physical handicap in the low leg muscles or have to drive prolonged hours with frequent foot pedaling. An experiment was designed to test the ergonomic heel rest with traditional foot pedal. Forty subjects participated in the experiment. Electromyography(EMG) was used to monitor the muscle activity and fatigue of right leg, and Electro-goniometer was used to measure the ranges of motions of the knee and ankle. A simulator of driver's seat was built for the experiment and the heel rest was installed on it. In order to examine the low muscle activity and range of motion, subjects used the foot pedal for 15 minutes repetitively for each experimental condition. Another 15 minutes test without the heel rest was also performed for comparison. The Root Mean Square(RMS) and Mean Power Frequency(MPF) Shift were used to quantify the level of muscle activity and local muscle fatigue. In results, statistically significant decreases of muscle activity and fatigue were found in all the low leg muscles. The range of motion of the knee and ankle joint also decreased when the heel rest was used. The mechanism of the heel rest effect was discussed in this study. This type of heel rest can be applied to real driving situation after ensuring the safety, or overcoming the psychological discomfort possibly due to unfamiliarity.

다자 중심적 사용성 평가 방법의 구조화 과정

김정룡,이하연,최영철,Kim, Jung-Yong,Lee, Ha-Yeun,Choi, Young-Cheol 대한인간공학회 2005 大韓人間工學會誌 Vol.24 No.2

In order to minimize a biased view of evaluators in usability test, a multiple evaluation method so called Multi-Centered Usability Evaluation Method(MCUEM) was suggested and structured in this study. To use MCUEM, the existing evaluation methods were re-categorized into 'developer and evaluator-centered', 'evaluator-centered', 'user-centered', 'evaluator and user-centered', and the 'developer, evaluator, and user-centered methods. Furthermore, in order to verify the relevance of MCUEM, the usability of mobile phone was tested in this study. In results, it was found that different evaluation methods generated greatly different results, that showed the risk of using a particular usability method due to different perspectives of evaluators. At the same time, it was found that MCUEM could greatly minimize such biases. Therefore, it was concluded that using MCUEM could help the usability engineer design a test protocol with a minimal risk of bias due to different perspective of evaluators.

고속도로 건설현장의 인적오류 예방을 위한 실무자용 도구 개발

김정룡(Jung Yong Kim),윤상영(Sang Young Yoon),조영진(Young Jin Cho) 대한인간공학회 2011 大韓人間工學會誌 Vol.30 No.1

Objective: The aim of this study is to reclassify human errors and to develop hands-on tools to apply the new classification for preventing human error accidents in highway construction site. Background: The main cause of accidents in highway construction was reported as the carelessness of workers. However, such diagnosis could not help us operationally prevent accidents in real workplace. Method: The accidents in highway construction were reanalyzed and the causes of human error were reclassified in order to educate and improve the awareness of human error in highway construction. Field survey and interview with safety managers and workers were conducted to find the causal relationship between the actual accidents and the human errors. Results: The most frequently observed human errors in highway construction were classified into six categories such as mis-perception, distraction, memory fail, slip, cognition error and mis-judgment. In order to provide hands-on tools to increase the awareness of human error in construction field, the human error checklist and card sorting diary were developed. Especially, the card sorting diary was designed to increase the ability in human error inspection of safety manager at construction site. Moreover, posters were developed based on actual accident cases. Conclusion: We suggested that the improved awareness and analytical report on checklist, card sorting diary and posters for construction field could collectively prevent the accident. Application: The classification of human error, hands-on tools and posters can be directly applicable on highway construction site. This analytical and collective approach preventing human error-related accident could be extended to other construction workplaces.

작업부하 평가를 위한 생체역학적 측정방법

김정룡(Jung Yong Kim),박지수(Ji Soo Park),조영진(Young Jin Cho) 대한인간공학회 2010 大韓人間工學會誌 Vol.29 No.4

It is necessary to quantitatively evaluate the workload of workers in order to improve the level of safety and efficiency as well as to prevent workers from musculoskeletal disorders. The purpose of this study is to introduce biomechanical methods that are largely used to quantitatively evaluate workload. The biomechanical methods use kinematics and kinetics to analyze the movement and force of biomechanical body. Motion analysis, joint angle measurement, ground reaction force, mathematical model, and electromyography (EMG) were introduced as a tool or device for biomechanical evaluation. In this study, the special feature of each method was emphasized and important tips for field measurement were summarized. The information and technique disclosed in this summary can be used to evaluate and design the workplace better by effectively control the workload of field workers.

휴대전화 설계를 위한 연령대별 사용자 특성

김정룡(Jung Yong Kim),김성훈(Sung Hoon Kim),조영진(Young Jin Cho) 대한인간공학회 2010 大韓人間工學會誌 Vol.29 No.3

The purpose of this study is to investigate the user characteristics in different age groups by investigating the level of satisfaction and preference of design and function of mobile phone. 160 subjects participated in the experiment. Subjects with different ages were selected and divided into four groups: young age group (20 to less than 45), 1<SUP>st</SUP> middle age group (45 to less than 55), 2<SUP>nd</SUP> middle age group(55 to less than 65), and elderly group(over 65). A questionnaire was developed based on the previous design guideline, and additional questions were made to test newly developed function and design of the mobile phone. In particular, depth interviews were conducted in order to have a proper response from old subjects who have difficulties in completing written questionnaire. In result, it was found that except for price the major criterion to purchase mobile phone was the design, and the function of phone was the next except for elderly group. In the case of elderly group, the screen size is the first. Statistical results indicated that 37.5% of the young age group, 22.5% of 1<SUP>st</SUP> middle age group, 22.5% of 2<SUP>nd</SUP> middle age group and 10.0% of the elderly group preferred the design to function when they purchase mobile phones. Most elderly people were not satisfied with the supplementary function of the mobile phone. The 1<SUP>st</SUP> middle age group did not know exactly how to use the supplementary service although they were willing to use it. Regarding the emotional preference on the type of phone, the sliding type was preferred most. Current results can be used to anticipate the future trend of mobile phone and design a user-friendly product for the aged population.

User Experience를 고려한 자동차 전조등 설계 방안

김정룡(Jung Yong Kim),윤상영(Sang Young Yoon),민승남(Seung Nam Min),이호상(Ho Sang Lee) 대한인간공학회 2010 大韓人間工學會誌 Vol.29 No.4

The aim of study is to suggest the design procedure of automobile headlamp by considering driver's experience in regard of the visibility and glare during nighttime driving. The characteristics of driver were investigated in terms of the drivers' cognitive ability and reaction time, headlamp specification and visibility, light source and glare. And, the degree of visual discomfort was categorized and recognized as a tool to represent the subjective user experience. The UX point of view was stated when the existing results were seemingly lacking of it. The visual comfort and safety of elderly drivers were also discussed by reviewing the studies of ageing regarding the visibility and driving responses. Finally, this study suggested how to reduce the negative effect of nighttime driving due to the height of headlamp, angle of lighting, color spectrum, discomfort glare, source of light by using the UX perspective and methodology.

휴대전화와 MP3에 사용되는 Wheel Navigation Key의 사용성 평가

김정룡(Jung?Yong Kim),정현욱(Hyun?Wook Jung),민승남(Seung Nam Min) 대한인간공학회 2009 大韓人間工學會誌 Vol.28 No.3

The aim of the study is to investigate the usability of wheel navigation key(WNK) recently adopted for the new models of mobile phone and MP3 product. In this study, an experiment was designed to evaluate the functional benefit of WNK by using a performance test. A questionnaire was also used to examine the personal preference. In results, a significant difference was found in performance time between wheel-type and button-type product. In general, the difference was more significant as subject's skill level was higher. In particular, the performance time was significantly shortened with the WNK when a searching task was required, but push button was an effective interface for simple search task among beginners. Therefore, the wheel navigation key can be used to improve the usability of product by reducing the searching time in mobile phone and mp3. For practical application, the user's level of skill needs to be considered to maximize the effect of interface when choosing WNK or push button.

생체신호 측정을 통한 운전자의 감정적 안정상태 평가

김정룡(Jung Yong Kim),박지수(Ji Soo Park),윤상영(Sang Young Yoon) 대한인간공학회 2011 大韓人間工學會誌 Vol.30 No.1

Objective: The aim of this study is to introduce a methodology to assess driver's emotion stability by using bio-signals. Background: Psychophysiological analysis of driver's behavior has been conducted to improve the driving safety and comfort. However, the variability of bio-signal and individual difference made it difficult to assess the psychophysiological status of drivers that can be expressed as emotional stability of drivers. Method: Two experimental studies were reviewed and summarized. New techniques assessing emotional stability of drivers were explained. Statistical concept and multidimensional space were used to identify the emotionally stable conditions. Conclusion: Psychophysiological approach can provide information of driver's emotional status. The experimental methodology and algorithm used in this study showed the possibility of parameterization of psychophysiological response. Application: Currently measured statistical and geometrical data can be further applied to develop an interactive device monitoring and reacting driver's emotion when driver experiences emotionally unstable or uncomfortable situation.

3 분할유동좌판의 골반후방회전 감소효과 분석

김정룡(Kim Jung Yong),임성균(Im Sung Kyun),김정원(Kim Jung Won),이상훈(Lee Sang Hoon) 한국HCI학회 2020 한국HCI학회 학술대회 Vol.2020 No.2

본 연구는 일자형 요추의 원인이 되는 골반후방회전을 일으키는 일반 의자의 단점을 보완하기 위해 개발된 3 분할유동좌판의자의 효능을 실험하기 위해 설계되었다. 본 연구에서는 착석 시의 곧게 세운 자세와 구부정한 자세에서 근활성도와 골반회전 각도 및 만족도를 일반의자와 비교하고자 하였다. 실험참가자는 남자 대학생 6 명을 대상으로 실험을 진행했다. 의자 별로 척추세움근, 배곧은근, 배바깥빗근의 근활성도와 골반회전각도를 곧게 세운 자세(Erect sitting) 로 1 분(구간 1), 구부정한 자세 (Slump sitting) 로 1 분 (구간 2), 같은 자세로 8 분 후 1 회를 추가로 측정하였다(구간 3). 구부정한 자세를 취할 시 초기와 후기를 각각의 구간(구간 2,3)으로 설정하여 분석을 실시했다. 근활성도 분석 결과 구간 3 에서 3 분할유동좌판의자에 앉았을 때가 일반의자에 비해 배곧은근의 근활성도는 유의미하게 낮았고 반면 척추세움근의 근활성도는 유의미하게 높았다. 골반회전각도 분석 결과 전 구간에서 3 분할유동 좌판에 착석했을 때의 골반 후방회전각도가 비교적 작았다. 설문조사 분석 결과, 부위별 주관적 만족도 조사결과에서 허리, 오금부위에서 일반의자에 비해 긍정적인 평가를 받았다. 이러한 결과는 3 분할 유동 좌판의 움직임으로 골반의 후방 회전을 방해하여 요추의 만곡각을 유지시켜 주는 것으로 해석할 수 있다. 결론적으로 기능성 3 분할 좌판을 가진 의자가 일자 요추를 예방할 수 있다는 가능성을 보여주었고 사용성을 개선한다면 상용화도 가능할 것으로 기대된다.

들기/내리기 작업 시 소음과 배경음악이 몸통근육 피로도에 미치는 영향

김정룡(Jung Yong Kim),신현주(Hyun Joo Shin),이인재(In Jae Lee) 대한인간공학회 2008 大韓人間工學會誌 Vol.27 No.3

The purpose of this study was to define the effects of noise and background music on the trunk muscle fatigue during dynamic lifting and lowering tasks. Six healthy male subjects with no prior history of low back disorders participated in this study. The participants were exposed to two levels of background noise such as 40㏈ noise and 90㏈ noise and three levels of background music such as no music, slow music, and fast music. Six different combinations of background noise and background music were played while the participants were performing the lifting task at 15% level of Maximum Voluntary Contraction. Electromyography signals from six muscles were collected and fatigue levels were analyzed quantitatively. In results, the 90㏈ noise increased trunk muscle fatigue and slowed down the recovery. The trunk muscle fatigue was the lowest when the fast music was played for as background. After recovery, the 90㏈ noise increased trunk muscle fatigue. The trunk muscle fatigue was the lowest when the slow music was played for as background. The results can be useful to manage the cumulative fatigue of trunk muscles due to background noise and music during repetitive lifting and lowering tasks in industry.