• Journal of Korean Society of Forest Science
• /
• v.90 no.3
• /
• pp.388-397
• /
• 2001

In forestry, where improvement of labor environment is quite impossible, improved posture would result in direct effects by preventing waste of physical strength, prevention of accidental injury caused by fatigue accumulated on certain body parts, and prevention of human error by inattentiveness due to weakened body. Therefore, this research carried on analysis of working posture in manual forest work(thinning using chain-saw, salvage cutting using chain-saw, clearing using hand saw, clearance of twiner using sickle, pruning using saw with a long handle, and tending of young growth using sickle) using OWAS analysis system. According to the OWAS method, percentage of OWAS action categories III and IV in the tasks using chain-saw and sickle was higher than another tasks. For the compared middle skillful worker group and low skillful worker group at felling work using chain-saw, percentage of OWAS action categories IV in middle skillful worker group was 5.1%, and low skillful worker group was 14.1%.

• Korean Institute of Interior Design Journal
• /
• v.17 no.3
• /
• pp.131-138
• /
• 2008

This research is on a seating posture happening at a chair in a cinema and looked into various changes in a posture through the analysis of bodily movement in a established space like a cinema. Through the behavioral analysis of a seating posture in a limited space, each behavioral characteristic shown by a male and female and interdependent relations with a limited space were grasped. The conclusion through the above research work was as follows: 1) This research suggested a frame of analysis by dividing a seating posture into the side and upper part and was able to analyze its subsequent change characteristic of a seating posture by a male and female. 2) As for the side posture, a male was found to change fewer postures than a female, but as for the upper posture, there appeared a high frequency in posture change in case of a female. 3) As for time of staying in the side posture, a female was found to keep up a specific posture, and relatively a male changes his postures frequently while appreciating a movie; likely, as for the upper posture, it was found out that there existed a difference between the preference for the upper posture and time to keep it up. 4) A male and female were establishing a comfortable environment through their change in a posture, and there appeared changes in a posture the most within every 10 minutes in both the side and upper part postures. 5) As for the correlation between a initial posture and keep-up posture, it was found that a male tend to pursue a comfortable posture as time goes by, while a female kept up a comfortable one from her initial seating posture.

• IE interfaces
• /
• v.24 no.4
• /
• pp.387-395
• /
• 2011

This study was aiming to examine work time, frequency, work environment, and postures of retail grocery store workers to evaluate the risk of musculoskeletal disorders. An ergonomic evaluation was conducted using job analysis and posture analysis. The four most time-consuming tasks were inspecting (27.4%), arranging (21.4%), cutting (17.6%), and displaying (15.6%). The height and length of the shelves evaluated in the field was inappropriate for workers. The most common posture was a standing posture with neutral back, and bent head, right upper arm, lower arms, and hands. Finally, this paper concluded that 'arranging,' 'cutting,' and 'displaying' seemed more stressful than other operations. The result of the ergonomic evaluation would contribute to design a better workspace in ergonomics.

• Korean Journal of Agricultural Science
• /
• v.40 no.3
• /
• pp.209-214
• /
• 2013

This study examined the work time, work posture, and work intensity for the actual measurement step in forest road the design work that was being carried out. The measurement of the forest road was being carried by a team of three workers and a team of four workers. The examination of work time found that the measurement of 1km took about 8 hours for the four-worker team and 12 hours for the three-worker team. The examination of work intensity found that the energy metabolic rates of the three-worker team were lower than four-worker team. Because their energy consumption per minute decreased as their work time and rest time increased. Furthermore, when appropriate rest time was applied according to work time, the energy metabolic rate decreased and the work intensity became lower. The four-worker team was more advantageous from the time and cost aspects of the forest road measurement work. Furthermore, as the rest time was very low compared to the work time, more efficient forest road measurement work would be possible if the work intensity was lowered by considering the rest time when calculating the standard work time.

• Journal of the Ergonomics Society of Korea
• /
• v.26 no.1
• /
• pp.29-37
• /
• 2007

This study was performed to evaluate the characteristics of transmitted vibration to hand-arm system under different work posture while operating a light-weighted powered hand grinder. For the experiment, 8 different types of wrist posture (natural, unlar-flexion, radual-flexion, flexion, extension, complex posture, and etc.) and 3 types of feed force (20[N], 50[N], 70[N]) were considered. 10 male subjects were employed to polish metal plate with a hand grinder. All of them were normal and healthy with no history and symptom of the work related musculoskeletal disorders in the dominant hand. Vibration acceleration data were recorded with sampling rate, 2048[Hz]. In addition, unweighted overall R.M.S. acceleration at the tool and wrist, and transmissibility between them were used to evaluate factors from the recorded tri-axial vibration acceleration. The results indicate that transmissibility of natural wrist posture was significantly higher than others. In addition, as the feed force becomes larger, the vibration was transmitted in large quantities to hand-arm system through radius.

• PNF and Movement
• /
• v.17 no.2
• /
• pp.253-261
• /
• 2019

Purpose: The purpose of this study was to identify the causal relationship between workplace stress and working posture and the development of work-related neck pain in office workers. Methods: The study participants included 62 office workers who had not experienced neck pain in the previous 12 months. A battery of measures to evaluate potential workplace risk factors in an office setting were conducted at baseline, and the 12-month incidence of work-related neck pain was reported via monthly questionnaires. Survival analysis was used to evaluate the longitudinal relationship between the workplace risk factors and the development of work-related neck pain. Results: The incidence of work-related neck pain was 1.91 (95% CI: 1.06-3.45) per 100 person months. The incidence of neck pain was predicted to be less likely to happen when workers had a more upright thorax posture during computer work (hazard ratio, 0.94; 95% CI: 0.89-0.99). However, stress may deteriorate the preventative effects of other risk factors on neck pain and showed a positive relationship with episodes of neck pain (hazard ratio, 1.37; 95% CI: 1.03-1.84). Conclusion: Understanding the psychophysiological effects of neck pain may explain the development of neck pain in office workers. Our interest in prevention plans and treatments should therefore involve a multifactorial pathology of neck pain in the workplace.

• Journal of the Ergonomics Society of Korea
• /
• v.32 no.5
• /
• pp.469-474
• /
• 2013

Objective: The purpose of this study was to analyze the risk factors of MSDs for the types of office work. Background: Physical risk factors of VDT(Video Display Terminal) associated with shoulder and neck musculoskeletal disorders(MSDs) include static work postures and workstation status. Method: In this study, office work was divided into data search, data entry and design work(drawings, etc.), and then we were surveyed 7 major work places which was included these works. We recorded working postures and obtained still images, depending on the types of office work. Then, RULA(Rapid Upper Limb Assessment) and ROSA(Rapid Office Strain Assessment) were used to analysis the risk factors. Results: The results of RULA showed that design work was under risk levels and required change, but ROSA showed that data entry and design work were high risk. The RULA is to evaluate the level of risk factors based on the working posture; on the other hand, the ROSA is to consider the use of peripheral, same as chair, keyboard/mouse, monitor and computer workstations. Conclusion: Conclusions of this study, the office work is necessary to identify the risk factors caused by the use of peripheral, as well as working posture.

• Physical Therapy Korea
• /
• v.30 no.3
• /
• pp.174-183
• /
• 2023

Background: Office workers experience neck or back pain due to poor posture, such as flexed head and forward head posture, during long-term sedentary work. Posture correction is used to reduce pain caused by poor posture and ensures proper alignment of the body. Several assistive devices have been developed to assist in maintaining an ideal posture; however, there are limitations in practical use due to vast size, unproven long-term effects or inconsistency of maintaining posture alignment. We developed a headphone and necklace posture correction system (HANPCS) for posture correction using an inertial measurement unit (IMU) sensor that provides visual or auditory feedback. Objects: To demonstrate the test-retest reliability and concurrent validity of neck and upper trunk flexion measurements using a HANPCS, compared with a three-dimensional motion analysis system (3DMAS). Methods: Twenty-nine participants were included in this study. The HANPCS was applied to each participant. The angle for each action was measured simultaneously using the HANPCS and 3DMAS. The data were analyzed using the intraclass correlation coefficient (ICC) = [3,3] with 95% confidence intervals (CIs). Results: The angular measurements of the HANPCS for neck and upper trunk flexions showed high intra- (ICC = 0.954-0.971) and inter-day (ICC = 0.865-0.937) values, standard error of measurement (SEM) values (1.05°-2.04°), and minimal detectable change (MDC) values (2.92°-5.65°). Also, the angular measurements between the HANPCS and 3DMAS had excellent ICC values (> 0.90) for all sessions, which indicates high concurrent validity. Conclusion: Our study demonstrates that the HANPCS is as accurate in measuring angle as the gold standard, 3DMAS. Therefore, the HANPCS is reliable and valid because of its angular measurement reliability and validity.

• Proceedings of the Safety Management and Science Conference
• /
• 2001.11a
• /
• pp.139-143
• /
• 2001

Work-related injurieshave become the issue in the twentieth century. Musculoskeletal disorders are the most common work-related injuriesand the most frequent from of work-related i11-health (more than 50％ of total work-related injuries (BLS 1990)). The workers at copy shops have complained of pain in their back, legs, and shoulders. Most of them work for more than 8 hours a day. They have claimed that their pains were associated with repetitive and continuous work over a long term. The purpose of this research is to suggest an ergonomically comfortable redesign of the copy machine. This study was performed by conducting a survey of copy shop workers who have complained of job-related physical pain, and analyzing their working postures. The copy machine was ergonomically modified to reduce the workers' pain. The VIS10N 3000 software was used to analyze the posture. The analysis showed significant difference in the ranges of back and neck motion (p<0.05).

• Korean Journal of Agricultural Science
• /
• v.38 no.1
• /
• pp.101-108
• /
• 2011

In forest work, working conditions are very hard to improve. The proper distribution of work time and good posture is believed to bring about direct improvements such as accident prevention. On this, this study has analyzed forest workers' posture and their working hours in order to improve their working conditions in stone channel work. Authors has chosen several core elements of stone channel work to focus on, which include stone masonry, excavation of bed, moving stone, directing work, choosing stone, and breaking stone. The ratio of real working time over total working time was shown as 84.6%. As for the time ratio of each elemental work over the real working time, the stone masonry was 60.4%, the directing work was 15.1%, moving stone was 12.1%, choosing stone was 7.1%, breaking stone was 3.3%, and excavation of bed was 2.0%. According to the analytical results provided by OWAS, the ratio of category III (Work posture has a distinctly harmful effect on the musculoskeletal system) has shown that moving stone turned out 65.2%, choosing stone was 61.5%, stone masonry was 46.1%, breaking stone was 14.3%, excavation of bed was 12.5% and directing work was 6.8%. Furthermore, the ratio of category IV (Work posture with an extremely harmful effect on the musculoskeletal system) has shown that excavation of bed turned out 37.5%, breaking stone was 28.6%, stone masonry was 27.3%, choosing stone was 7.7%, moving stone was 6.1% and directing working was 4.5%. These results are expected to be utilized for the improvement with respect to both working methods in the stone channel work and the workers' working posture.