• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.355-356
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• 2010

• 대한예방의학회:학술대회논문집
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• 1996.10a
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• pp.231-232
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• 1996

• Journal of the Korean association of regional geographers
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• v.4 no.1
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• pp.77-98
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• 1998

In general, spatial imbalance in regional growth is a major cause of social and political conflicts within a state. In Korea, this inequality has functioned as a threat to the state's integration. With the economic development policies by regional industrialization over the past three decades, most of the industrial activities have been concentrated in Seoul and Pusan metropolitan areas, which are surrounded by Kyonggi, Kyongnam provinces respectively. Compared to these areas, Chonnam and Chonbuk provinces have lagged behind in economic development. Therefore, in order to increase the regional economic development of the southwestern region in Korea, the central government has been enforcing several policies aimed at regional industrialization since the 1980s. The purpose of this study focuses on the regional economic impacts of a newly established industrial estate-Yulchon industrial complex- which would act as a regional growth center in the Kwangyang bay area. The Kwangyang bay area consists of several industrial estates such as Kwangyang Iron and Steel Co. and its related industrial complex, Chuam rural industrial estate, Yeochon industrial complex, and so on. In addition, the Kwangyang container port was constructed in 1997. The Kwangyang bay area has been changing to a new industrial district in the southwestern part of Korea as a result of industrialization policies which were activated by central government. The Yulchon industrial complex, which is expected to be completed in 2001, would draw many manufacturing plants. For example, Hyundai Motors Co. has a plan to locate a new automobile assembly plant within the estate. As the plan has high probability to be realized, it will be interesting to study the effects a new automobile assembly plant and its related production linkages have on the region. This study is to estimate the expected structural characteristics of automobile production activities in Yulchon. The following details will be discussed: the regional economic impacts of a new automobile industry in Yulchon industrial complex, the production linkage formation via hierarchical subcontracting systems, the alternative strategies to promote the growth of regional economies, and the scheme to improve the auto-parts and components industry in Kwangju and Chonnam provinces by establishing auto-mobile production function. Automoblie industry generally gives great influences on not only regional economies but the related industries, for example, the firms producing automotive components. If a new plant producing automobiles and its related firms producing components are to be established in Yulchon, they will affect on the regional development directions and change the regional characteristics of industrial structure. In order to increase the spread effects of the new industry in Yulchon industrial complex, almost all of the automobile production processes must be organized concurrently within a limited range of distance. There is an imperative that the co-operation system should be structured between the assembly firm and many firms producing its components. In addition to those, it would be required such as the effective division of labors between the firms, much more capabilities in the technical innovations, and the reconstruction of interrelationship between the labor unions and the firms' managers.

• Journal of the Korean Society for Precision Engineering
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• v.27 no.12
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• pp.75-83
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• 2010

Every mechanical part for mass production has dimensions with tolerances in engineering drawing. Tolerance is given to guarantee assemble parts together satisfying functional requirements and dimensional constraints. Tolerance is essential factor for standardization of parts or assembly and has huge influence on manufacturing cost. It will be desirable to have tolerances as broad as possible for minimizing manufacturing cost. This paper describes tolerance analysis of u-joint assembly that is a part of automobile steering system. Within the range of tolerances of parts, accumulated effect is estimated by arithmetic calculation, probability theory and Monte carlo simulation. Each result is compared to investigate the method for increasing productivity.

• Journal of the Ergonomics Society of Korea
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• v.30 no.2
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• pp.297-302
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• 2011

Many WMSDs(work-related-musculoskeletal disorders) have been reported in diverse industries and have also attracted much attention in recent years. Neck-related MSD is generally known as one of common WMSDs, especially it happens to workers who are working at the automobile assembly plants and/or shipyards. The awkward posture is considered as a main cause of neck-related MSDs. A neck supporter was developed to prevent neck-related MSDs, and 10 males were recruited to evaluate the newly developed neck supporter by measuring subjective discomfort ratings of whole body, shoulder, neck and neck-muscle activities. Muscle activities from four neck muscle groups(left/right sternocleidomastoid and upper/middle trapezius) were measured while simulating an automobile assembly task. Results showed that the neck supporter help to significantly improve subjective discomfort for whole-body, shoulder as well as neck body parts. The analyses of muscular activities also showed that the activities of left/right sternocleidomastoid muscles were statistically decreased with the neck supporter in this study. The muscle activities of upper/middle trapezius in case of wearing the neck supporter were not significantly different with the muscle activities in case of no-wearing the neck supporter. Overall findings verified that the neck supporter might help to prevent neck-related MSDs based on the current study.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.16 no.3
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• pp.276-283
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• 2006

Work-related musculoskeletal disorders (WMSDs) were a major source of disability and lost work time after 'Foreign Currency Crisis(1998-2000)' in Korea. There is considerable evidence documenting the association between psychosocial risk factors and work disability due to WMSDs. But, there is not much in Korea. The present study aimed to explore the predictive association between the changed working conditions and WMSDs after 'Foreign Currency Crisis' in Korea. A study sample of 8,670 automobile assembly workers were recruited for this study. A structured-questionnaire was used to assess general characteristics, working conditions, and information concerning medical treatment of WMSDs. After adjustment for sociodemographic factors, increased overtime work(OR=1.22), daily work time(OR=1.20), work speed (OR=1.32), number of workers(OR=0.83), supervisory control(OR=1.39), physical load(OR=1.39), and mental load (OR=1.25) were all founded to be significantly associated with WMSDs. This study has shown the importance of changed working conditions in the occurrence of WMSDs. Therefore, it will be necessary to reduce WMSDs with controlling both physical and psychosocial factors.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.33 no.2
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• pp.103-114
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• 2023

Objectives: This study was conducted to evaluate hand-arm vibration (HAV) exposure levels due to the use of power hand tools and to evaluate the determinants in the automobile assembly process. Methods: The exposure level to HAV was evaluated for 30 work lines in five assembly processes (body, engine, chassis, door, and design) that use air-powered tools and battery-powered tools and operate in circulation for two hours. The 2-hr equivalent energy vibration acceleration, A (2), of the task was measured. The 8-hr equivalent energy vibration acceleration, A (8), was estimated in consideration of the number of tasks that can be performed per day by each process. In addition, a survey on the working environment was conducted with workers exposed to vibration. Results: The geometric mean of the HAV exposure level, A (2), for a total of 30 tasks was 2.51 m/s², and one case was 10.30 m/s², exceeding TLV (2hr). The HAV exposure level of A (8) was evaluated from 1.03 m/s² to 5.36 m/s². A (2) showed a statistically significant difference (P<0.01) for each process, and the chassis process (GM=3.90 m/s²) was the highest. The larger the tool size and the longer the tool length, the higher was the vibration acceleration when using a battery-powered tool than an air-powered tool (P<0.01). Battery-powered tool users showed higher dissatisfaction on all items than did air-powered tool users. Conclusions: As a result of this study, it is necessary to implement a program to reduce the HAV exposure levels.

• IE interfaces
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• v.16 no.2
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• pp.211-221
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• 2003

This paper introduces a simulation study regarding the design for the installation of Color Rescheduling Storage (CRS) in an automobile factory. In the painting shop the colors of vehicles are changed frequently according to the assembly schedule. When the color of a vehicle is changed from one to another, the cleaning process of painting-gun is necessary and it generates costs. Therefore many of the automobile manufacturers equip the CRS in front of the Top Coat Booth of the painting shop. The major objective of CRS is to reduce the change over cost in the painting process by grouping vehicles having same color. In this paper the configuration of CRS and the input/output algorithms are explained. The suggested system is verified using simulation models and experiments are conducted. Finally the best alternative is suggested by sensitivity analysis and evaluation of investment feasibility.

• Journal of the Korea Safety Management & Science
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• v.14 no.4
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• pp.259-264
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• 2012

Automobile market was grown up by 1.7% at the first half of 2012 comparison with 2011 in China and this growth trend will be continued for a while. Under this market environment the China automobile companies expand the production capacity and result in heightening the intense competition for companies. This paper deals with the more efficient production line and production logistics through SPS(Synchronized Production System) with construction of MES(Manufacturing Execution System) in H automobile company in China. In plastic painting line we can simultaneously prepare the production quantity and delivery time according to assembly production plan by introducing MES. We can reduce the excess production and result in extreme reduction of inventory.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.9 no.1
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• pp.56-72
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• 1999

Airborne concentrations of welding fumes in which 13 different metals such as Al, Cd, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Si, Sn, Ti, and Zn were analyzed were measured at 18 factories including automobile assembly and manufactures, steel heavy industries and shipyards. Air samples were collected by personal sampler at each worker's worksite(n=339). Blood levels of Cd, Cu, Fe, Mn, Pb and Zn were also measured from samples taken from 447 welders by atomic absorption spectrometry and compared with control values obtained from 127 non-exposed workers. The results were as follows ; 1. Among various welding types, $CO_2$ welding 70.2 % were widely used, shielded metal arc welding(SMAW) 22.1 % came next, and rest of them were metal inert gas(MIG) welding, submerged arc welding(SAW), spot welding(SPOT) and tungsten inert gas(TIG) welding. 2. Welding fume concentration was $0.92mg/m^3$($0.02{\sim}15.33mg/m^3$) at automobile assembly and manufactures, $4.10mg/m^3$($0.02{\sim}70.75mg/m^3$) at steel heavy industries and $5.59mg/m^3$($0.30{\sim}91.16mg/m^3$) at shipyards, respectively, showing significant difference among industry types. Workers exposed to high concentration of welding fumes above Korean Permissible Exposure Limit(KPEL) amounted to 7.9 % and 12.5 %, in $CO_2$ welding and in SMAW at automobile assembly and manufactures and 62.7 % in $CO_2$ welding, and 12.5 % in SMAW at shipyards, and 66.2 % in $CO_2$ welding and 70.6 % in SMAW at steel heavy industries. 3. Geometric mean of airborne concentration of each metal released from welding fumes was below one 10th of KPEL in all welding types. Percentage of workers, however, exposed to airborne concentration of metals above KPEL amounted to 16.8 % in Mn and 7.6 % in Fe in $CO_2$ welding; 37.5 % in Cu in SAW, 30 % in Cu in TIG; and 25 % in Pb in SPOT welding. As a whole, 76 Workers(22.4%) were exposed to high concentration of any of the metals above KPEL. 4. There were differences in airborne concentration of metals such as Al, Cd, Cr, Cu. Fe. Mn, Mo, Ni, Pb, Si, Sn, Ti and Zn by industry types. These concentrations were higher in shipyards and steel heavy industries than in automobile assembly and manufactures. Workers exposed to higher concentration of Pb above KPEI amounted to 7.4 % of workers(7/94) in automobile assembly and manufactures. In shipyards, 19.2 % of workers(19/99) were over-exposed to Mn and 7.1 % (7/99) to Fe above KPEL. In steel heavy industries, 14.4 %(21/146), 7.5 %(11/146) and 13 %(19/146) were over-exposed to Mn, Fe and Cu, respectively. As a whole, 76 out of 339 workers(22.4%) were exposed to any of the metals above KPEL. 5. Blood levels of Cd, Cu, Fe, Mn, Pb, and Zn in welders were $0.11{\mu}g/100m{\ell}$, $0.84{\mu}g/m{\ell}$, $424.4{\mu}g/m{\ell}$, $1.26{\mu}g/100m{\ell}$, $5.01{\mu}g/100m{\ell}$ and $5.68{\mu}g/m{\ell}$, respectively, in contrast to $0.09{\mu}g/100m{\ell}$, $0.70{\mu}g/m{\ell}$, $477.2{\mu}g/m{\ell}$, $0.73{\mu}g/100m{\ell}$, $3.14{\mu}g/100m{\ell}$ and $6.15{\mu}g/m{\ell}$ in non-exposed control groups, showing significantly higher values in welders but Fe and Zn.