• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.10
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• pp.80-87
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• 2021

Our study introduces an improved modular agricultural platform to provide convenience to agricultural workers. We upgrade the platform design in three parts, namely, by adding a 458 pattern tire, electricity control, and four-wheel steering function, to improve the platform performance. Results showed that the upgrades enhanced the platform performance and reduced its overall weight as compared with the existing platform. To demonstrate the performance of our improved platform, we conducted five types of experiments with respect to the climbing angle, variable width, attitude control, speed, and obstacle passing.

• Journal of the Ergonomics Society of Korea
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• v.31 no.5
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• pp.637-646
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• 2012

Objective: The aim of this study was to develop the adaptive device for severe physical disabilities using smart device in the driving simulator and its performance evaluation. Development of appropriate driving adaptive device for the people with serious physical limitation could contribute to maintain their community mobility. Background: There is lack of adaptive driving devices for the people with disabilities in Korea. However, if smart device systems like iPod and iPhone are used for driving a car, the people with serious physical limitations can improve their community mobility. Method: Both gyroscope and accelerometer from iPod were used to measure the tilted angle of the smart device for driving. Customized Labview program was also used to control three axis motors for steering wheel, accelerator and brake pedals. Thirteen subjects were involved in the experiment for performance evaluation of smart device in simulator. Five subjects had driver licenses. Another four subjects did not have driver licenses. Others were people with disabilities. Results: Average driving score of the normal group with driver license in the simulator increased 46.6% compared with the normal group without driver license and increased 30.4% compared with the disabled group(p<0.01). There was no significant difference in the average driving score between normal group without driver license and disabled group(p>0.05). Conclusion: The normal group with driver license showed significantly higher driving score than other groups. The normal group without driver license and disabled group could improve their driving skills with training in simulator. Application: If follow-up studies would be continued and applied in adapted vehicle for on road environment, many people with more severe disabilities could drive and improve the quality of life.

• Journal of the HCI Society of Korea
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• v.10 no.2
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• pp.13-19
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• 2015

Display technology has recently made enormous progress. In particular, display companies are competing each other to develop flexible display. Curved display, as a precursor of flexible display, are now used for smart phones and TVs. Curved monitors have been just introduced in the market, and are used for office work or entertainment. The aim of the current study was to investigate whether the curvature of a 42" multi-monitor affects postural control when it is used for entertainment purpose. The current study used two curvature levels (flat and 600mm). Ten college students [mean(SD) age = 20.9 (1.5)] with at least 20/25 visual acuity, and without color blindness and musculoskeletal disorders participated in this study. In a typical VDT environment, each participant played a car racing video game using a steering wheel and pedals for 30 minutes at each curvature level. During the video game, a pressure mat on the seat pan measured the participant's COP (Center of Pressure), and from which four measures (Mean Velocity, Median Power Frequency, Root-Mean-Square Distance, and 95% Confidence Ellipse Area) were derived. A larger AP (Anterior-Posterior) RMS distance was observed in the flat condition, indicating more forward-backward upper body movements. It can be partly due to more variability in visual distance across display, and hence longer ocular accommodation time in the case of the flat display. In addition, a different level of presence or attention between two curvature conditions can lead to such a difference. Any potential effect of such a behavioral change by display curvature on musculoskeletal disorders should be further investigated.