• 대한인간공학회지
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• 제32권1호
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• pp.145-152
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• 2013

Objective: The aim of this study is to develop an ergonomic office chair that has an alarm function for the unbalanced sitting postures. Background: Contrary to expectation, it is reported that office workers sit on their chairs much more in unbalanced postures during daily work. Even though an office worker uses an ergonomically good-designed chair and begins their work in a good sitting posture, his/her posture is likely to shift to the unbalanced bad posture. Therefore, a posture alarm system would be very helpful in keeping office workers' good postures. Method: We developed a prototype chair with four load cells under a seat pan and one load cell beneath a backrest. Through some experiments, we set the criteria for unbalanced bad postures then implemented the criteria into the alarm system of the prototype chair. The chair called e-BASE chair could detect unbalance postures and show alarms for chair users. We also enhanced back support by developing a step-wised folding backrest. Results: The e-BASE chair showed better performance in interface pressure distributions and balanced posture ratio in VDT work. Conclusion: The ergonomic chair with posture alarm function(e-BASE chair) was developed. It showed better performance in seat pressure distribution and in keeping good posture during office work. Application: The posture alarm system and folding backrest can be applied to the new models of office chair.

• 자동차안전학회지
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• 제12권1호
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• pp.52-61
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• 2020

In recent years, the increasing interest in health-care requires the industrial products to be well-designed ergonomically. In the commercial vehicle industry, several researchers have demonstrated the driver's posture has great effect on the orthopedic desease such as fatigue, back pain, scoliosis, and so on. However, the existing sensor systems developed for measuring the driver posture in real time have suffered from inaccuracy and low reliability issues. Here, we suggest our smart vehicle seat system capable of real-time driver posture monitoring by using the air bag sensor package with high sensitivity and reliability. The ergonomic numerical model which can evaluate a driver's posture has been developed on the basis of the human body segmentation method followed by simulation-based validation. Our experimental analysis of obtained pressure distribution of a vehicle seat under the different driver's postures revealed our smart vehicle system successfully achieved the driver's real-time posture data in great agreement with our numerical model.

• 자동차안전학회지
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• 제15권3호
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• pp.59-65
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• 2023

As advanced driving assistance system (ADAS) and autonomous driving performance continue to improve, existing crash accidents and crash types are changing. Accordingly, the collision angle and the seating posture of the occupant are changed. It is necessary to study how the occupant injury mechanism changes according to these different crash types. In this regard, a representative crash test mode was derived when the automatic emergency braking system (AEB), one of the autonomous driving performance, was applied to the representative car-to-car crash scenario in Korea. The derived crash test mode was used to analyse the mechanisms of collision injuries according to both impact angle and the occupant seating posture (reclined seat-back angle). The results obtained through this study can be utilized as reference data for the development of new crash evaluation methods and improvements in crash restraint systems for enhancing crash safety.

• 자동차안전학회지
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• 제15권4호
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• pp.48-57
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• 2023

With the advance of autonomous vehicle technology various sitting posture is possible like relax position (inclined seating posture). Parametric study was done with MADYMO, a mutibody dynamics solver, to investigate the effect of sitting posture in different frontal crash modes, full frontal, 40% offset, and angled rigid barrier crash as well as various impact speeds. Hybrid III 50th male and 5th female dummies were used to figure out the difference induced by occupant weight and dimension. Restraint system parameters complying to current safety protocols like NCAP are studied if they still work effectively in relax position which is feasible with autonomous vehicles.

• 대한안전경영과학회지
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• 제11권4호
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• pp.77-83
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• 2009

The purpose of this study was to examine the relative effectiveness of immediate feedback and informational prompt on safe sitting behaviors that may cause VDT syndromes. Participants were three white color workers and an ABCB within-subject design was adopted. Safety Posture System was developed specifically for the present study. The system could detect participants' unsafe sitting postures using sensors and provide feedback and prompt on the computer monitors. The results indicated that both immediate feedback and informational prompt considerably increased safe sitting behaviors. More importantly, the immediate feedback was more effective than the informational prompt in increasing safe sitting behaviors.

• 한국안전학회지
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• 제26권6호
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• pp.97-103
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• 2011

This study compared the effects of different frequencies of self-monitoring on safe sitting postures. Participants were four office workers. The dependent variable was the safety percentage for four body positions. The independent variable was self-monitoring frequency: high and low self-monitoring frequencies. Results showed that the safety percentage increased when self-monitoring was introduced. However, the effects of the two different self-monitoring frequencies on safe performance were not statistically different.

• 대한안전경영과학회지
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• 제23권2호
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• pp.25-30
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• 2021

The possibility of developing musculoskeletal disorders increases with the length of service of the worker. Musculoskeletal disorders can occur when performing repetitive and forceful movements. Therefore, Cargo drivers operate repeatedly in the wrong posture for a long time. When loading and unloading a cargo, the cargo driver works repeatedly with force. Cargo operators are also exposed to musculoskeletal disorders in the working environment due to poor posture and repetitive movements. In this study, we are going to conduct a study on the level of awareness and prevention of the possibility of musculoskeletal disorders in cargo drivers for long periods of time. As a result of the study, the factors that cause musculoskeletal disorders in each group can occur during the long-term operation and preparation of drivers.

• 한국산림과학회지
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• 제110권2호
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• pp.210-216
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• 2021

우리나라 모든 산업에서 근골격계질환은 작업자들의 안전에 큰 영향을 미치고 있으며, 산림작업은 산업안전보건법에 따라 근골격계 부담작업으로 분류된다. 특히 벌도 및 가지제거작업은 주로 인력작업으로 실시되고 있으며, 작업원의 안정성 확보를 위해 작업자세에 대한 평가가 필요하다. 따라서 본 연구는 체인톱을 이용한 벌도 및 가지제거작업의 작업자를 대상으로 세가지 인간공학적 분석 도구(OWAS, RULA, REBA)를 이용하여 위험도를 평가하고, 평가기법별 작업자세에 대한 영향인자를 분석하였다. 벌도와 가지제거작업자세의 위험도는 RULA, OWAS, REBA 순으로 높게 평가되었으며, 대부분 2-3단계로 작업자세의 즉각 변경조치는 요구되지 않았다. 하지만 벌도작업에서 허리와 다리를 굽힌자세와 가지제거작업에서 벌도목 위에서 작업하는 자세는 위험도가 매우 높게 분석되었다. 또한 벌도작업의 경우 산지경사, 가지제거작업의 경우는 지상에서부터 벌도목 높이가 작업위험도 평가에 영향이 높은 것으로 분석되었다. 따라서 산림작업에 있어서 작업자의 안전성을 확보하기 위해 작업부하가 낮은 자세(벌도작업: 쪼그리는 자세, 가지제거작업: 허리와 다리가 곧은 자세)로 작업하는 것이 바람직한 것으로 사료된다.

• 대한안전경영과학회지
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• 제14권2호
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• pp.11-22
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• 2012

The purpose of this study was to compare drivers' postures with different car pedal systems and skilled levels. Fourteen subjects participated in this experiment and for three-dimensional analyses, six cameras (Proreflex MCU-240, Qualisys) were used to acquire raw data. The parameters were calculated and analyzed with Visual-3D. In conclusion, the patterns of pelvic, hip, knee and ankle joint angles were different as to pedal systems and skilled levels, and distal joints ROA pelvis have large angles. ROA(range of angle) of a double pedal system was small, but ROA of a single pedal system was large. These findings suggested that we should improve a present single pedal system.

• 대한인간공학회지
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• 제32권5호
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• pp.475-480
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• 2013

Objective: In this study, virtual reality was adopted to consider ergonomic factors in yacht design. Virtual human which is the same actual human was created in virtual environment using Digital Human Modeling which has been used in the manufacturing communities to design better workplaces and maximize the safety of workers. Background: During the past 40 years yachting has expanded from being, generally speaking, a minority sport - too expensive for the large majority of people - into a major recreational activity practiced by millions all over the world. Many new yacht designs have appeared and number of professional, as well as amateur designers has increased steadily. But they had not considered ergonomic factors in yacht design. Method: Worker's posture, traffic line and workload had been analyzed in sailing yacht. After the caution level was evaluated, we pointed out clues which had high workload and interference. To reduce workload, we applied ergonomic principles for improving working conditions and environments in Digital Human Model. Results: We found the space problems and workload of postures. Conclusion: (1) Unnatural posture of crews was sustained. (2) Workload that occurs in the human body was overloaded. (3) Crew's work space was very narrow. Application: This study will be applied the new ergonomic design of yacht.