• Journal of Information Technology Services
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• v.12 no.4
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• pp.435-447
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• 2013

If we use a smartphone to analyze and detect falling, it is a huge advantage that the person with a sensor attached to one's body is free from awareness of difference and limitation of space, unlike attaching sensors on certain fixed areas. In this paper, we suggested effective posture analysis of smartphone users, and fall detecting system. Suggested algorithm enables to detect falling accurately by using the fact that instantaneous change of acceleration sensor is different according to user's posture. Since mobile applications working on smart phones are low in compatibility according to mobile platforms, it is a constraint that new development is needed which is suitable for sensor equipment's characteristics. In this paper, we suggested posture analysis algorithm using smartphones to solve the problems related to user's inconvenience and limitation of development according to sensor equipment's characteristics. Also, we developed fall detection system with the suggested algorithm, using hybrid mobile application which is not limited to platform.

• Proceedings of the Society of Korea Industrial and System Engineering Conference
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• 2002.05a
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• pp.63-68
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• 2002

This study performed to evaluated musculoskeletal disorders(MSDs) during sitting work. The musculskeletal system is affected by various work factors such as strength, weight, posture, repetition, duration and exertion. Ergonomic study on sitting work is necessary to evaluate these factors affecting human body. But the strength and work load data by the work factors are insufficient in Korea. Therefore, this study evaluated the work load using the elcctromyogram(EMG) and measured the arm strength by arm posture and push pull work during sitting work. to evaluated muscle load, the vertical height and horizontal angle of arm were adjusted around acromion. And EMG data were recorded on pc during the test.

• Industrial Engineering and Management Systems
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• v.6 no.2
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• pp.146-157
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• 2007

This paper discusses two algorithms for recommending notebook computer (NBC) and workstation adjustments so that the user can assume an ergonomic seated posture during NBC operation. Required input data are the user's anthropometric data and physical dimensions of the NBC and the workstation. The first algorithm is based on an assumption that there are no workstation constraints while the second algorithm considers the actual seat height and work surface height. The results from the algorithms include recommendations for adjusting the NBC (tilt angle of the NBC base unit, angle between the base and screen units, and base support height) and the workstation (heights of seat support and footrest, and distance between the body and the NBC).

• Journal of the Ergonomics Society of Korea
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• v.31 no.2
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• pp.281-289
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• 2012

Objective: The purpose of this study is to evaluate the potential risk of shoulder muscle at particular working postures in sitting. Background: The cause of shoulder pain needs to be specifically studied in relation with particular shoulder postures to prevent shoulder MSDs in workplace. Method: In this study MVC, fatigue and subjective workload were investigated depending on the change of shoulder posture. An experiment was designed to evaluate the six shoulder muscles at nine shoulder postures including the combination of 30(adduction), 0, 30(abduction) degrees and 60, 90, and 120 degrees of shoulder flexion. Surface electrodes were attached to the middle trapezius, inferior middle trapezius, anterior deltoid, posterior deltoid, serratus anterior and teres major. Thirteen subjects participated in the experiment. Dependent variables were RPE (rating of perceived exertion), MVC(maximum voluntary contraction) and MPF(mean power frequency) shift by EMG (electromyography). Results: The middle trapezius and inferior middle trapezius were not significantly fatigued at all postures. The decline of MPF slope was less than 10% at all postures. The anterior deltoid was significantly fatigued all postures. The decline of MPF slope was more than 10% at all postures. The posterior deltoid was significantly fatigued 30 degrees of adduction and 90 degrees of flexion. And, neutral and 30 degrees of abduction postures were fatigued more than 90 degrees of flexion. The serratus anterior was significantly fatigued except for 30 degrees of adduction and 60 degrees of flexion posture. The teres major was significantly fatigued except for neutral and 60 degrees of flexion, 30 degrees of abduction and 60 degrees of flexion posture. Conclusion: It was found that a certain muscle was fatigued fast at particular posture compared to other muscles, which would mean that a certain shoulder muscle at particular posture could be easily exposed to the risk of musculoskeletal disorders than other muscles. Application: It is expected that the result can be applied to design workplace using shoulder muscles.

• Safety and Health at Work
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• v.9 no.2
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• pp.192-202
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• 2018

Background: Work-related musculoskeletal disorders are accumulative disorders that are most frequently found in agricultural farmers. The purpose of this study was to investigate factors that affect symptoms resulting from work-related musculoskeletal disorders among Cambodian farm workers working in fruit plantations in the eastern region of Thailand. Methods: The Nordic Musculoskeletal Questionnaire, Rapid Upper Limb Assessment, and Hazard Zone Jobs Checklist techniques were used to interview 861 farmers who participated in the study. Results: The data showed that men who had been working for >10 years were more at risk of neck pain than those working for <1 year with adjusted odds ratio (aOR) 1.66, 95% confidence interval (CI) (1.90, 14.5). Among women those who had been working for >10 years experienced lower back pain with aOR 8.13, 95% CI (1.04, 63.74), compared with those who had been working for <1 year. Men whose tasks required raising the arms above shoulder height had a risk factor contributing to neck pain of aOR 1.68, 95% CI (1.08, 2.61) when compared with those who did not work with this posture, and women had aOR 1.82, 95% CI (1.07, 3.12) when compared with those who did not work with this posture. Conclusion: Based on the results of this study, it is recommended that work-related health conditions are monitored in migrant plantation workers to reduce the risks of musculoskeletal disorders.

• Proceedings of the Safety Management and Science Conference
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• 2009.04a
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• pp.69-78
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• 2009

The goal of this study is to propose the effective method of investigating the injurious factors and making improved plans that prevents the workers against musculoskeletal disorders at an autoparts company and the same business field with similar working conditions and process. A questionnaire were adopted to analyze the symptoms of workers' musculoskeletal disorders, and an ergonomic assessment method such as RULA, OWAS were performed to find out harmful factors of workplace and working posture. Based on the result of the evaluation, to enhance the working environment, improvement of worktable, working space, tools, and outfit was suggested, and induction of mechanical system was also suggested. It can be concluded that the method and process described in this paper could be helpful for diagnosing the musculoskeletal disorders and making improvement plans to the autopart company and the same business field with similar working conditions and process.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.465-472
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• 2022

Manual material handling is the one of the leading causes for musculoskeletal disorders (MSDs) and lower back discomfort. According to a study, construction formworkers suffer greater rates of muscular injuries and related illness due to manual activities. However, there is still a paucity of information on MSD, preventive posture issues, and corresponding solutions for construction aluminum formworkers. As a result, MSD and disregard of worker health and safety continue to exist at construction sites. Although preventive measures and strategies have been studied in previous research, we believe it is imperative to shed light on this problem through this study. This study aims to 1) implement a simple and cost-effective elevated bench to reduce MSDs, and 2) determine the rapid upper limbs assessment (RULA) and Ovako working posture analyzing system (OWAS) action catagory of workers in different postures to assess their MSD conditions and obtain an optimal position and posture using the Jack human modeling software and simulation tool. The study findings reveal a considerable reduction in MSD discomfort and which posture is acceptable in post-intervention instances.Thus results provide inexpensive and simple ergonomic interventions with favorable RULA and OWAS ratings that can be applied at construction sites. This study demonstrates workstation ergonomic intervention cases that can aid in understanding the urgency of applying existing research strategies into practice.

• Journal of the Ergonomics Society of Korea
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• v.34 no.2
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• pp.191-198
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• 2015

Objective: As a cue for desired mood, we attempted to identify types of sitting postures when people are involved in various tasks during their working hours. Background: Physical behaviors in reaction to user contexts were studied, such as automated posture analysis for detecting a subject's emotion. Sitting postures have high feasibility and can be detected robustly with a sensing chair, especially when it comes to an office. Method: First, we attached seven sensors, including six pressure sensors and one distance sensor, to an office chair. In Part 1, we recorded participants' postures while they took part in four different tasks. From the seven sensors, we gathered five sets of data related to the head, the lumbar, the hip, thigh pressure and the distance between the backrest and the body. We classified them into four postures: leaning forward, upright, upright with the lumbar supporting, and leaning backward. In part 2, we requested the subjects to take suitable poses for the each of the four task types. In this way, we compared the matches between postures and tasks in a natural setting to those in a controlled situation. Results: We derived four types of sitting postures that were mapped onto the different tasks. The comparison yielded no statistical significance between Parts 1 and 2. In addition, there was a significant association between the task types and the posture types. Conclusion: The users' sitting postures were related to different types of tasks. This study demonstrates how human emotion can interact with lighting, as mediated through physical behavior. Application: We developed a posture-based lighting system that manipulates the quality of office lighting and is operated by changes in one's posture. Facilitated by this system, color temperatures ranging between 3,000K and 7,000K and illuminations ranging between 300lx and 700lx were modulated.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.23 no.1
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• pp.43-51
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• 2017

Background: This study was carried out to compare the effects of shoulder stabilization exercise and thoracic extension exercise including deep neck flexor exercise on posture and pain targeting physical therapists and occupational therapists with forward head posture. Methods: A total of 30 physical therapists and occupational therapists (15 males, 15 females), who are working in the nursing hospital at Daejeon, were randomly divided into a shoulder stabilization group (n=10), a thoracic extension exercise (n=10), and a control group (n=10), and 3 times were carried out for 8 weeks. Results: In the results of all measurements, 2 groups except for the control group showed a significant change in the recovery of forward head posture, and the should stabilization exercise group showed a relatively superior effect compared to the thoracic extension exercise group. Conclusions: These results of a study will be a basic data for the development of the forward head posture exercise therapy program.

• Journal of the Ergonomics Society of Korea
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• v.29 no.2
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• pp.225-239
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• 2010

A high prevalence of farmer's work-related musculo-skeletal disorders (MSDs) have been reported in precedent studies. Risk factors - physical, chemical, biological, ergonomic risk factor etc. - in farm-work were identified by previous studies. To prevent farmers from exposing to them and reduce, Agricultural Safety Technology were introduced and used on farm. The purpose of this study is to review and summarize the agricultural safety technology on farm in Korea. According to strategy principles, this technology is classified as four criteria - workload reduction by reducing awkward posture, workload reduction by using manual material handling aids, Comfort improvement by protecting worker from hot, cold environment and work efficiency improvement by workplace redesign and cultivation modification. This technology includes transporting tools, working cloth, personal protective equipment, and pesticide-proof Clothing. Anthropometric study of Korean farmers was also carried out to support the development of equipment and clothes. In long terms, it needs to precaution activity from risk factors by using cultivation modification and working improvement. Although working condition gets better and workload reduce by this technology, it required customized safety technology in each crops - rice cultivation, horticulture and livestock farming. And farmers should use the assistive technology and participate voluntarily in ergonomic intervention program.