• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.20 no.8
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• pp.761-766
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• 2010

The goal of this study is to analysis natural frequency for different static postures of human leg. To perform this research human leg is modeled by multi-body modeling for the musculoskeletal system. This leg model has biarticular muscles which acting on two joints and the muscles represents some of the major muscles, such as hamstring, of the upper and lower limbs. To obtain each static equilibrium position energy method is employed and to analysis natural frequency linearization method for constrained mechanical system is employed. Static equilibrium position depends on some parameter or condition such as hamstring stiffness or external force. Making a change these parameter the aim of this research can be performed.

• Journal of Fashion Business
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• v.25 no.3
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• pp.71-89
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• 2021

The purpose of this study was to design posture braces for rounded shoulders by examining characteristics of incorrect postures of rounded shoulders. The review of information in literature on rounded shoulder postures, correction exercise methods, and posture correction devices, has prompted this study to determine the design and material of a proper posture brace for rounded shoulders. In order to develop the pattern of a posture brace for rounded shoulders for women, the study carried out a comfort evaluation of the braces based on the 2D patterns through drafting method by utilizing the body measurements and relational formulae associated with the major body measurement such as bust circumference and on the 3D patterns of the brace which were obtained from 3D human model of women in their early 20s in Korea. Differences in angles were noted when 2D and 3D patterns of shoulder posture braces were compared. The side neck point was relocated farther outside in the 3D pattern to allow additional flexibility in the back-neck area, and the shoulder band was lowered by 14.8°, increasing armhole area comfort. The upper hemline of the front panel was found to rotate upward at an angle of 22.0° as the underarm point of the 3D pattern moved upwards than the underarm point of the 2D pattern, which enhanced comfort in the abdomen area. The 3D designs of shoulder posture brace was preferred in this study, as they significantly improved comfort while conducting fit evaluation compared to the 2D patterns of shoulder posture brace.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.15 no.2
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• pp.114-123
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• 2005

We analyzed the demographic and job features of 197 shipyard workers with work-related musculoskeletal disorders(WMSDs) compensated by the Industrial Accident Compensation Insurance Act, and the features of the disorders, the causes of operation and the induced behaviors. The three shipbuilding companies surveyed were located in Busan Metropolitan city and Gyungsangnam-do. The results were as follows. 1. The ages of WMSDs patients in shipyard were $43.6{\pm}8.6$ and the job tenure was $14.3{\pm}5.6$. The 40's of them was 40.1%, and the 30's was 29.4%. Patients less than 5 year-work duration were 85.3%, and ones more than 16 year-work duration 6.6%. In occupations, welders were 32.5%, pre-welders 17.3%, and setting engineers 6.6%. 2. The causes of WMSDs in shipyard were works(95.4%) and outer crash or accident shock (3.6%). Based on the standard of the NIOSH induced behaviors, the causes were awkward posture (62.9%), excessive movement(19.3%) and repetitive movement(13.7%). 3. The compensated WMSDs by body part was the highest, 36%, in the spines, 32.0% in both the upper limbs and the spines, and 14% in the upper limbs. The number of cases of WMSDs in body were 96 in the cervical, 79 in the lumbar and 72 in the shoulders. 4. As a result of chi-square test(${\chi}^2$) between diagnosis and operation in body, welding and spot welding had the most diagnoses in all parts of the body among other occupations. Chi-square test(${\chi}^2$) between diagnosis and induced behavior in body showed that awkward postures recorded the highest rate and repetitive movements was the second. 5. The most hazardous occupation was the welding(incidence rate=9.7) and the most hazardous behavior was the awkward posture.

• Journal of the Korean Society of Costume
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• v.54 no.4
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• pp.75-84
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• 2004

Stage costumes perform not only the instrumental but also the expressive functions. The major goal of this study is to develop the functional and aesthetic costume designs for musical players considering the characteristics of instruments. players’ postures. The scope of this study is restricted to the musical costumes for female adult soloists playing the wind and string instruments. This study is composed of theory research, empiricalresearch and manufacturing a real costume. First, theory research contains theory of musical costumes and that of pure musical areas. Concept, characteristics and wearing effects are analysed in theory of musical costumes. Second, designs of instruments and playing postures are analysed in the theory of pure musical areas. Proper and improper designs are compared based on the survey asking the favorite designs of 56 wind and string players. Third, I manufacture a stage costume for a harpist. The conclusions of this study are as follows. First, wind and string players think the functionality of costumes more importantly than the esthetic sense. And there are differences in design preferences for different playing postures. Second, string Players basically use arms, fingers and the upper body. Wind players use fingers more than string players and do abdominal breathing. Third, string players think the design of arms and sleeves because of frequent usage of bow and prefer the design without sleeves. On the contrary, wind players think the silhouette importantly because of standing playing posture. Fourth, players don't think that the accessory is not important and want it so long as it doesn't hinder playing. Fifth, shoes plays more important role than costume in case of playing posture with using pedals and moving legs frequently. Lastly, both wind and string players prefer the design with simplicity and comfort most.

• Journal of Fashion Business
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• v.15 no.2
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• pp.145-159
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• 2011

The study aimed to analyze the status quo of manufacturing work environment and the work clothes' clothing comfort and wearer mobility of welding and grinding work processes in the machine and shipbuilding industries in South Korea. A questionnaire survey was conducted for the study, which consisted of questions about work clothes' clothing comfort and wearer mobility according to body parts. The findings derived from the research were: the high impact levels of work environment factors on welding and grinding work processes were noise, metal fragment, superheat, toxic gas, UV ray factors. Subject workers' assessment of work clothes' clothing pressures were in the levels between 3 (i.e. moderate) and 4 (i.e. comfortable) in a range of 5-point scale. The impact levels of wearer mobility factor were high on the work processes of welding and grinding in machine and grinding in shipbuilding. While welding process in shipbuilding showed a 'moderate' wearer mobility level and this was because its work postures were uncomfortable yet the rate of the motion change was low. The consideration to develop the work clothes specialized for certain work processes should include the materials' protecting performance from the hazardous work environment factors; and work clothes' designs that provides workers with maximized clothing comfort and wearer mobility for bending or tilting postures of upper, lower and lateral body parts defined in the study.

• Journal of Fashion Business
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• v.16 no.6
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• pp.21-35
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• 2012

In consideration of the injuries and deaths occurring at manufacturing sites due to the use of inappropriate work clothes or safety devices, this study aims to categorize manufacturing work processes to develop functional work clothes for heavy industries including the automobile, machine and shipbuilding industries in South Korea. Defining the features of the work environments and work postures of these industries provided for a categorization of the work processes which would enable the development of suitable work clothes for each work process' category. The results of the study based on a questionnaire survey are as follows: Work process category 1, including steel panel pressing and auto body assembly, final inspection (in automobile) and inspection (in machine), requires work clothes with upper body and arm mobility and performance to protect from the toxic fume factor. Work process category 2, consisting of welding (in automobile), cutting-and-forming (in machine) and attachment-and-construction (in shipbuilding), requires clothing elasticity, durability and heat and fire resistance. Work process category 3 comprising welding and grinding in the machine and shipbuilding industries, requires work clothes' tear resistance and elasticity, particularly for lateral bending mobility, and work clothes' sleeves' and pants' hemlines with sealed designs to defend against iron filing penetration, as well as incombustible and heat-resistant material performance. Finally, work process category 4, including painting in machine and shipbuilding, requires work clothes with waterproofing, air permeability, thermal performance, elasticity, durability and abrasion resistance.

• Korean Journal of Applied Biomechanics
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• v.14 no.3
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• pp.1-15
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• 2004

The purpose of this study was to investigate the kinematic variables of the upper part of the body for 8 elderly men during walking. For this study, kinematic data were collected using a six-camera (240Hz) Qualisys ProReflex system. The room coordinate system was right-handed and fixed in space, with righted orthogonal segment coordinate systems defined for the head, trunk, and pelvis. Based on a rigid body model, reflective marker triads were attached on the 3 segments. Three-dimensional Cartesian coordinates for each marker were determined at the time of recording using a nonlinear transformation(NLT) technique with ProReflex software (Qualisys, Inc.). Coordinate data were low-pass filtered using a fourth-order Butterworth with cutoff frequency of 6Hz. Three-dimensional angles of the head, trunk, and pelvis segment were determined using a Cardan method. On the basis of each segment angle, angle-angle plot used to estimated the movement coordinations between segments. The conclusions were as follows; (1) During the support phase of walking, the elderly people generally kept their, head the flexional and abductional posture. Particularly, the elderly displayed little internal/external rotation. (2) The elderly people showed extensional and external rotation postures in the trunk movement. Particularly, It showed the change from adduction into abduction at the heel contact event of the stance phase. (3) The elderly people showed almost same pelvis movement from the flexion into extension, from the abduction into adduction, and from internal rotation into external rotation at the mid stance and toe off of the stance phase.

• Journal of the Ergonomics Society of Korea
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• v.35 no.2
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• pp.67-74
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• 2016

Objective: The aim of this study is to develop a farming shovel to reduce workload, which helps farmers lower the risk of musculoskeletal disease. Background: Most of work using farming tools including shovels requires repetitive works and awkward postures on body parts, and it could possibly cause work-related musculoskeletal disorders. It is necessary to develop and distribute farm equipment and tools in order to reduce physical workload. Method: To improve the most uncomfortable task perceived by ten farmers during the work with a shovel, the improved shovel was designed and made as a prototype for experiment for the comparison of the existing and improved shovels. Twenty males were recruited for this experiment, and muscle activity (%MVC) of six body parts and subjective discomfort ratings by body parts while working with a shovel were measured. A paired t-test was performed to compare physical workload between the existing shovel and the developed one. Results: A shovel applying foothold tied between shaft and blade was designed, which can help workers reduce repetitive bending of back and pressures for upper limbs while digging soil. According to compared evaluation of the developed shovel and the existing shovel, the developed shovel's %MVCs in all experimental muscles were significantly lower than those of the existing shovel. The developed shovel showed the biggest drop in perceived subjective discomfort rating of back, followed by arm and neck, compared to the existing shovel. Conclusion: It was confirmed that attaching a foothold to a shovel was an effective way of reducing workload in back and upper limbs during digging. Application: In the near future, if we put the prototype of developed shovel to practical use after making up for defects, it will help farm work environment be healthier and safer.

• Proceedings of the KAIS Fall Conference
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• 2011.05b
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• pp.1044-1047
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• 2011

본 연구는 소방대원의 현장 작업자세 평가와 분석을 통하여 소방대원의 근골격계 부담작업 유해요인을 분석하고자 한다. B시에 소재하고 있는 소방서의 남자 소방대원을 대상으로 소방 현장에서 많이하는 자세 중 요구조자 이송작업자세, 방수작업자세, 유압구조장비 작업자세, 만능도끼작업 자세를 인간공학적 평가 기법인 Rapid Entire Body Assessment(REBA), Rapid Upper Limb Assessment(RULA)와 NIOSH Lifting Equation(NLE)를 이용하여 평가하고 분석하였다. 자세 분석결과, RULA 분석에서 모든 작업이 최고 점수인 7점으로 평가되었고 REBA는 5점에서 10점까지로 RULA분석에 비하여 낮은 점수를 나타내었다. 따라서, 소방대원들의 작업환경과 자세에 문제가 많다는 것을 알 수 있었다.

• Journal of Korean Institute of Industrial Engineers
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• v.39 no.2
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• pp.105-108
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• 2013

Drivers' sitting strategies are considered in car seat design. Existing research has identified representative sitting strategies by visual inspection of seating pressure measurements collected from a small sample size of drivers. The present study recruited 20 female and 20 male participants, measured seating pressure, and classified sitting strategies by cluster analysis. The participants' sitting postures were classified based on seating pressure distribution into mid-back and scapular, mid-back and lumbar, and lumbar sitting strategies for the upper body and hip concentrated, hip and mid-thigh concentrated, and hip and mid-thigh distributed sitting strategies for the lower body. The effects of gender and occupant package layout (OPL) on sitting strategy were nout found significant. The identified sitting strategies would be of use for the design and evaluation of an OPL and a seat.