• Journal of the Ergonomics Society of Korea
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• v.25 no.3
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• pp.61-66
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• 2006

Awkward work postures in workshop highly affect on work-related musculoskeletal disorders(WMSDs). Especially, in automobiles assembly process, these awkward work postures of workers may cause serious injury and illness. This study is to compare the performance among the evaluation tools which can measure the work-loads caused by the awkward work postures in automobiles assemble process. RULA, REBA and TVAL(Toyota Verification of Assembly Line) are used as the evaluation tools. The 85 jobs selected in the automobiles assembly process are applied to the three tools and their performances are analyzed after the evaluation of the work-load in each job. Through various measures of performance such as statistical test, DUNCAN test, regression test etc., the tendencies and characteristics among them are analyzed in detail.

• Journal of Korean Institute of Industrial Engineers
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• v.24 no.3
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• pp.447-455
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• 1998

It is important to identify and evaluate poor working postures properly to prevent work-related musculoskeletal disorders. The purpose of this study is to develope a new upper body micropostural classification scheme for analyzing postural stress in industry. Most of the existing postural classification schemes were based either on the literature, or on simple biomechanical principles, or on a subjective ranking system. The scheme suggested in this study was based on perceived joint discomfort measured through experiment, in which nineteen subjects participated and the magnitude estimation method was employed to obtain subjects' joint discomfort. Also, the criteria for evaluating postural stress of working postures were presented for practitioners of health and safety to be able to redesign working methods and workplaces, which was based on maximum holding time by Miedema and other people. It is expected that the scheme developed in this study could be used as a valuable tool when evaluating working postures.

• Journal of the Korean Society of Safety
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• v.12 no.2
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• pp.146-152
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• 1997

The number of accidents due to slipping, falling and awkward postures are estimated to account for over forty percent of annual industrial accidents in Korea. To prevent such accidents, stability-maintaining capabilities of workers should be understood before any other approach. This research was aimed to analyze capabilities of the workers with the help of yours male students maintaining standing postures on a tiltable stability platform. The experimental result showed that tilting direction, height of pivoting point, and permissible degree of swaying made significant effects on stability-maintaining duration. Besides, humans are more capable of maintaining their standing body postures on a platform tiltable fore and aft rather than or one tiltable sideways. The number of falling or tripping supported this phenomenon. A mechanical and physical discussion on the stability was added.

• Journal of the Ergonomics Society of Korea
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• v.36 no.5
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• pp.589-599
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• 2017

Objective: The objective of this study was to measure the upper-limb motions and postures of grapes-harvesting tasks using electrical goniometers and analyze the upper-limb motions in a kinematic way to assess the risk of musculoskeletal disorders. Background: Grapes farmers are exposed to various risk factors of musculoskeletal disorders (MSDs) such as repetitive upper-limb motions, non-neutral postures, and manual handling of heavy items. The farmers have to use scissors repetitively while harvesting grapes with their being arms elevated over the shoulder height, which presumed to increase the physical workload. It has been reported that the grapes farmers feel the harvesting task as the one of the hardest work in cultivating grapes. We tried measure the wrist and elbow angles while the farmers were carrying out harvesting tasks to understand how much workload the work impose on the farmers, which can be helpful in making interventions of preventing musculosksletal disorders among grapes farmers. Method: We measured joint angles at the right wrist and elbow with a wireless measuring system with two electrical goniometers from five grape farmers. The grapes-harvesting task was classified into 6 different subtasks: 1) searching, 2) picking, 3) cleaning, 4) carrying, 6) storing, and 7) miscellaneous tasks. The subtasks were compared by mean angles, 10%, 50%, and 90% APDF values of wrist flexion/extension, ulnar/radial deviation, and elbow flexion. Results: The Kruskal-Wallis tests showed that the 10th percentiles of APDF of ulnar/radial deviation and flexion/extension of the wrist significantly differs among subtasks (p<0.05). It was found that the farmers assumed more deviated wrist postures in the ulnar direction when they picking and adjusting the grapes. The use of scissors seemed to force the farmers to severely bend their wrist in the directions of ulnar deviation and flexion. The grapes-harvesting task showed similar wrist postures and motion with poultry deboning and milking tasks. Conclusion: The grapes harvesting tasks make the farmers take ulnar deviated and extended postures in the wrist. The use of scissors makes them take more severely deviated postures in the wrist. Safety guidelines including use of ergonomic scissors can be provided to the farmers to improve their work conditions. Application: The results of this study can be used as a basic data for the development of safety guidelines for agricultural work.

• Journal of Korean society of Dental Hygiene
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• v.4 no.2
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• pp.265-276
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• 2004

The purpose of this study,was to find out health status, characteristics related to working conditions, occurrence of low back pain and its related factors among dental hygienists working in dental clinics, and, thus, to provide basic information necessary to set up some plans for preventing the occurrence of low back pains and improving working conditions for dental hygienists. The data were collected from 310 dental hygienists working at dental clinics in Pusan and Kyungnam area, including Masan, Changwon, Jinhae and Jinju, with a self-administered questionnaire and were analyzed finally for 295 records with SPSS for Windows(7.52K) program. The results were as follows : Working condition was considered to be fair by 562% of dental hygienists were thought to threaten their health in the dental clinics. About seventy percent of dental hygienists worked over ten hours a day and 72.8% were standing while working over 7 hours, 65% considered working hours too long. Health status was thought be more than average for 82.3% while more than half perceived certain degree of stress frequently. The rate of complaining low back pains among dental hygienists was 87.8% with pains more than medium level for 39.3%. The variables significantly related to the degree of low back pains were height, uncomfortable postures, type of working postures and the height of working table, while some variables including height, hours of working on the feet, the presence of hazardous work environment, uncomfortable postures, the presence of hazardous works, the amount of working hours, type of working postures and work-associated stresses, were significantly related to the number of symptoms for low back pains. Multiple regression analysis showed that occurrence of low back pains was significantly influenced by 5 factors such as subjective status of health, work-related stresses, the degree of perception to work environment, the degree of perception to the amount of working hours and age. In conclusion, it might be necessary to manage working conditions effectively by reducing working hours, making good postures while working and removing stressful conditions in order to reduce risk factors for the occurrence of low back pains among dental hygienists. Therefore good working postures, assignment of appropriate rest time and some programs for early detection, care and education of low back pains should be provided for the dental hygienists.

• Journal of the Korean Society of School Health
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• v.12 no.2
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• pp.321-337
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• 1999

The purpose of this study was to obtain basic data for the prevention and control of adolescent back pain through analyzing connections between study environments and physical posture. The subjects were 960 male general high school students in the Chonju area and the data were collected by a self-reported questionnaire from Mar. 17 to Mar. 22, 1999. The collected data were analyzed by a frequency, chi-square and t-test using an SPSS program. The results are as follows; 1) The experience rate of back pain perceived by subjects was 67.5% and by each grade: 1st-27.5%, 2nd-35.4%, 3rd-37.1%. The relationship between grades and the experience of back pain didn't show any significant difference. 2) The causes of back pain perceived by subjects such as 'postures are not good' was 56.7%, 'sitting too much time in a chair' was 39.1%, and 'too severe exercise' was 32.4%. 27.8% had back pain first during the 3rd grade of middle school, and 23.9% had it first during the 1st grade of high school. 3) Intensity of subjects' back pain spread from 'moderate' at 49.6%, to 'severe' at 16.4%. Concerning the frequency of back pain, 58.6% said it was 'irregalar'. 4) Among interventions to deal with back pain: 'move by exercising my back or ask friends to beat my back' was 41.0%, 'just bear it' was 23.1%, and at home 'don't have 'any treatment' was ranked first, at 54.9%. 5) The relationship between subjects' general characteristics and back pain experiences: height (t=-1.99, P=.046), sitting/height (t=-2.61, P=.009), self-perceived condition of health (${\chi}^2=23.530$, P=.000), family history (${\chi}^2=43.903$, P=.000) showed significant difference, but the kinds of transportation, sleeping postures, sleeping method and smoking didn't show significant differences. 6) The relationship between subjects' learning environment and back pain experiences, the height of students' desk and chair showed significant difference (${\chi}^2=23.054$, P=.000), but the sitting time didn't show significant difference. 7) The relationship between the characteristics of subjects' physical postures and back pain experiences: standing postures (${\chi}^2=15.105$, P=.001), and sitting postures (${\chi}^2=20.264$X2, P=.001) showed significant difference, but lifting postures didn't show significant difference.

• Journal of the Korean Society of Safety
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• v.13 no.1
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• pp.131-138
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• 1998

This field study was conducted to survey the effect of seating ＆ lighting conditions on work. The results were as follows ; Discomfortable parts of body caused by unsuitable sitting postures on work were low back 52.05%, leg 15.75%, neck 14.38% and arm 9.59%. Work conditions of sitting postures were needed arm rest, back rest of seat and adjustable seat height. Effect of work efficiency by lighting conditions were statistically significant relationship between glaring state of workstation and lighting state.

• Fashion & Textile Research Journal
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• v.14 no.5
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• pp.803-810
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• 2012

This study investigates the effect of nonverbal communication on trust, switching barrier, and repurchase intention. Sample subjects used in this study were customers of a fashion shop in Sunchon. The questionnaires were conveniently sampled from July 2010 to August 2010. Questionnaire data from 335 customers of a national brand were analyzed through a reliability analysis, factor analysis, and multiple regression analysis. The results of this study are as follows. First, nonverbal communication by the service provider was divided into 3 types, physical appearance and paralanguage, postures and proxemics, and facial expressions. Second, it was found that physical appearance and paralanguage, postures and proxemics, facial expression of nonverbal communication had a significant impact on customer trust. Third, given the relationship between nonverbal communication and switching barrier, it was represented that the postures and proxemics and facial expressions (except physical appearance and paralanguage) had a significantly positive influence on the switching barrier. Forth, physical appearance/paralanguage, postures/proxemics, and facial expressions (nonverbal communication) had a positive influence on repurchase intention. Fifth, given the relationship between trust and repurchase intention as well as switching barrier and repurchase intention, it was represented that trust and switching barrier have a significantly positive influence upon repurchase intention. According to the results of this study, the more positive nonverbal communication by the service provider then the higher the customer repurchase intention as well as trust and switching barrier. Fifth, given the relationship between trust and repurchase intention as well as switching barrier and repurchase intention, it was represented that trust and switching barrier have a significantly positive influence upon repurchase intentions.

• Journal of Oral Medicine and Pain
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• v.25 no.4
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• pp.383-394
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• 2000

This study was performed to investigate the effect of change of body posture on the rest position and the rotational torque movement of the mandible. Thirty dental students without any signs and symptoms of temporomandibular disorders and with natural dentition were selected for this study. Cervical inclination and the amount of the mandibular movement on protrusion, on left and right excursion, and on tapping in three body postures such as sitting position, supine position without pillow, and supine position with pillow were measured by goniometer, Cervical-Range-of-$Motion^{(R)}$, and mandibular tracking device, $BioEGN^{(R)}$ with $Rotate!^{(R)}$ program. The data obtained were classified and processed according to body posture and type of lateral guidance with SPSS windows program and the results were as follows: 1. There was significant difference among the three cervical inclinations by body postures. 2. Comparison of mandibular rest positions among body postures showed significant difference only for lateral distance in frontal plane, but comparison between before and after swallowing showed significant difference except for the lateral distance, vice versa. 3. Distance and amount of the rotational torque movement on protrusion and/or lateral excursions didn't show any difference by body posture. But by both body posture and lateral guidance type, there were slightly significant difference for some items. 4. A significant difference was shown for the rotational torque movement in frontal plane on tapping by body postures, for the lateral distance in frontal plane on sitting position by lateral guidance type, and for the rotational torque movement in frontal plane by both body posture and lateral guidance type.

• Physical Therapy Korea
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• v.22 no.1
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• pp.1-8
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• 2015

The purpose of this study was to compare the change in electromyography (EMG) activity in the gluteus maximus (G-max) and the gluteus medius (G-med) in subjects with and without chronic ankle instability (CAI) during three functional postures. Twenty four females were recruited for this study. Subjects were assigned into two groups: with CAI ($n_1=12$) and without CAI ($n_2=12$). The assessment postures were rotational squat, one leg stand above a gradient and crossed leg-sway. Electromyographic activities of the G-max and the G-med were recorded using surface EMG and was normalized using the maximal voluntary isometric contraction elicited using a manual muscle testing. Independent t-test was used to determine the statistical differences between two groups during the three functional postures. The comparisons of the three posture between two groups were performed using a one-way repeated analysis of variance. A Bonferroni adjustment used for post hoc analysis. The activation of EMG on G-max performing the one leg stand above a gradient and crossed leg-sway in subjects with CAI is significantly higher than normal group (p<.05). The activation of EMG on the G-max during the rotational squat was significantly increased, compared to those of the one leg stand above a gradient and crossed leg-sway (p<.05). The activation of EMG on G-med performing three exercise at CAI is significantly higher than normal group (p<.05). The activation of EMG on the G-med during the crossed leg-sway was significantly increased, compared to the rotational squat (p<.05). This study provides valuable information for clinician who research CAI.