• Journal of Preventive Medicine and Public Health
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• v.19 no.1 s.19
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• pp.16-30
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• 1986

In order to prepare the fundamental data for the improvement of noisy working environments and the effective hearing conservation program on workers exposed to industrial noise, the authors surveyed the working processes and evaluated the noise levels on 56 manufacturing industries in Pusan area from April to July in 1985. The results were summarized as follows : 1. The noise level was the highest in shipbuilding and repairing(95.6 dBA), and followed by steel rolling(94.0 dBA), manufacture of motor vehicles(93.1 dBA), manufacture of fishing nets(92.9 dBA), manufacture of testiles(92.5 dBA), iron and steel foundries(89.3 dBA), manufacture of metal products(89.1 dBA), preserving and processing of marine foods(87.0 dBA), manufacture of rubber products(85.3 dBA), manufacture of plywood(84.9 dBA) and manufacture of paints(84.5 dBA). 2. Among fifty surveyed working processes, the noise level of twenty-one processes (42%) exceeded the threshold limit value for 8 hours per day. 3. As the allowable exposure times by governmental threshold limit values to industrial noise level(dBA), cocking of shipbuilding and repairing and plating(CGL) of steel rolling were the shortest(30 minutes), and followed by assembling(rivet) of manufacture of motor vehicles(1 hour) weaving of manufacture of textiles and shot, machine, pipe laying of shipbuilding and repairing(2 hours). 4. By the result of octave band analysis on noisy working processes in excess of 90 dBA, the sound level was the highest at 2,000 Hz or 4,000 Hz. 5. It was recognized that the measurement of overall sound pressure level was also effective as octave band analysis in evaluating the industrial noise.

• The Journal of the Korean dental association
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• v.55 no.2
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• pp.139-155
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• 2017

The study of job satisfaction among female dentists is essential to improve the quality of their life. In this study, a job satisfaction survey of female dentists in Gwangju was performed and the factors affecting job satisfaction were examined. A survey of female dentists in Gwangju was conducted using a custom-designed and validated questionnaire which incorporated the Korean Dentist satisfaction Survey (KDSS) as well as questions regarding socio-demographics and professional characteristics. Satisfaction for each question was measured by a 5-point Likert scale. The final analysis was performed with 89 questionnaires, after excluding 3 non-response questionnaires. Analysis of the data for each group was carried out using a Mann-Whitney U test and Kruskal-Wallis H test. The reliability of the questionnaire was identified by the internal consistency of the survey using Cronbach coefficient. The data were statistically analyzed using SPSS (IBM SPSS Statistics 19, SPSS Inc, Chicago, Ill, USA). The level of statistical significance was set at p = 0.05. On analyzing with use of the above mentioned method, the following findings were observed: Income, leisure time, time for self-development, and overall job satisfaction were lower than the average, especially the percentage of dissatisfaction was much higher than that of satisfaction. Satisfaction was associated with age, duration of employment, and the number of assistants. The limitations of this study are the lack of an adequate sample size, convenience sampling during extraction, the lack of questionnaire items, the limitations of quantitative research, and failure to perform measurement in the non-response group. However, female dentists can be expected to achieve a more satisfactory and enhanced working environment if the research based on the current study is followed up in an expanded target group.

• Journal of Environmental Science International
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• v.26 no.9
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• pp.1013-1021
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• 2017

Exposure to Diesel Particulate Matter (DPM) potentially causes adverse health effects (e.g. respiratory symptoms, lung cancer). Due to a lack of data on Elemental Carbon (EC) exposure levels in underground copper ore mining (unlike other underground mining industries such as non-metallic and coal mining), this case study aims to provide individual miners' EC exposure levels, and information on their work practices including use of personal protective equipment. EC measurement was carried out during different work activities (i.e. drilling, driving a loader, plant fitting, plant operation, driving a Specialized Mining Vehicle (SMV)) as per NIOSH Method 5040. The copper miners were working 10 h/day and 5 days/week. This study found that the most significant exposures to EC were reported from driving a loader (range $0.02-0.42mg/m^3$). Even though there were control systems (i.e. water tanks and DPM filters) on the diesel vehicles, around 49.5% of the results were over the adjusted recommendable exposure limit ($0.078mg/m^3$). This was probably due to: (1) driver's frequently getting in and out of the diesel vehicles and opening the windows of the diesel vehicles, and (2) inappropriate maintenance of the diesel vehicles and the DPM control systems. The use of the P2 type respirator provided was less than 19.2%. However, there was no significant difference between the day shift results and the night shift results. In order to prevent or minimize exposure to EC in the copper ore mine, it is recommended that the miners are educated in the need to wear the appropriate respirator provided during their work shifts, and to maintain the diesel engine and emission control systems on a regular basis. Consideration should be given to a specific examination of the diesel vehicles' air-conditioning filters and the air ventilation system to control excessive airborne contaminants in the underground copper mine.

• Child Health Nursing Research
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• v.22 no.4
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• pp.336-345
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• 2016

Purpose: This study was conducted to describe health in optimal fitness (HOF) in young children born prematurely and to analyze factors affecting HOF in health status, investment resources, and anthropological values, based on HOF theory. Methods: A case-control study of 76 children with preterm births (PTB) was conducted at 24 to 42 months of corrected age. Their HOF status was evaluated based on height, weight, head circumference, and the Korean-Bayley Scale of Infant Development-II and classified as either HOF-achieved or HOF-uncertain in the domain of growth, development, and all together. Results: For growth, development, and all, 26.3%, 27.6%, and 47.4% of children, respectively, belonged to the HOF-uncertain group. Logistic regression analysis showed that longer length of hospital stay (${\geq}21days$; OR=7.8; 95% CI [1.5, 40.5]), worse scores on the Home Observation for Measurement of the Environment (HOME) (${\geq}38$; OR=0.1; 95% CI [0.0, 0.4]), having a working mother, (OR=5.7; 95% CI [1.2, 27.6]), and an older mother (${\geq}35years$; OR=8.8; 95% CI [2.1, 37.3]) were statistically significant contributors of HOF-uncertain in the domain of all. Conclusion: Findings show that young children born prematurely with prolonged stays in a neonatal intensive care unit and insufficient socioeconomic resources at home are more likely to exhibit delayed growth and development.

• The Journal of the Korea Contents Association
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• v.16 no.4
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• pp.100-113
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• 2016

Purpose: This study was performed to investigate the influence of children's hospital nurses' job characteristics and job stress on turnover intention. Method: The subjects were 148 nurses who have been working in 6 children's hospitals located in G city. Measurement tools used for this study included job characteristics were created by Lee, and modified by Hong, and job stress tool developed Kim & Ku and modified by Choi. And the tools used for assessing turnover intention were created by Mobley and Becker and modified by Kim. The collected data was analyzed using descriptive statistics, the independent t-test, one-way ANOVA, Pearson' Correlation and regression on SPSS 21.0 program. Result: Job challenge and job fitness among the sub-areas of job characteristics, job stress and salary were identified as factors influencing turnover intention. These factors explained 36.5% of variance of turnover intention. Conclusion: In conclusion, this results can be used to help the children's hospitals creates an environment where nurses can enhance Job challenge and job fitness also, reduce job stress which lead to turnover rate and turnover intention.

• Journal of Digital Convergence
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• v.15 no.3
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• pp.187-193
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• 2017

Objects Internet-based healthcare services provide healthcare and healthcare services, including measurement of user's vital signs, diagnosis and prevention of diseases, through a variety of object internet devices. However, there is a problem that new security vulnerability can occur when inter-working with the security weakness of each element technology because the internet service based on the object Internet provides a service by integrating various element technologies. In this paper, we propose a user privacy protection model that can securely process user's healthcare information from a third party when delivering healthcare information of users using wearable equipment based on IoT in a mobile environment to a server. The proposed model provides attribute values for each healthcare sensor information so that the user can safely handle, store, and store the healthcare information, thereby managing the privacy of the user in a hierarchical manner. As a result of the performance evaluation, the throughput of IoT device is improved by 10.5% on average and the server overhead is 9.9% lower than that of the existing model.

• Journal of the Korean Society of Physical Medicine
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• v.15 no.3
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• pp.69-77
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• 2020

PURPOSE: The aim of this study was to measure changes in spine inclination and thoracolumbar structure and morphology according to upper-extremity movements with and without resistance in order to evaluate the spine stability in workers. METHODS: Forty-eight middle-aged male workers (mean age, 40.48 ± 6.27 years) participated in this study. Using the spine analysis system, changes in the inclination of the spine and structure as well as shape of the thoracolumbar spine were measured. For posture measurement, the postures of standing, lifting the right and left arms (shoulder joint 90° flexion), and lifting with both arms were measured in random order. In addition, variables were measured using a resistance of 3 kg for each posture. The statistical significance level was set at α = .05 for all variables. RESULTS: There were statistically significant differences between the front and back inclinations of the spine, kyphotic curve of the thoracic spine, lordotic curve of the lumbar spine, rotation changes in the thoracolumbar spine, and rotation changes in the T4 vertebra (p < .05). However, there was no significant difference in the left and right tilts of the spine. In the post-hoc analysis, rotation changes in the T4 vertebra showed a significant difference in posture when resistance was applied to the left and right sides CONCLUSION: Causes of musculoskeletal diseases include excessive thoracic spine rotation, torsion, and hyperlordosis of the lumbar spine. Therefore, it is necessary to improve the working environment in order to ensure a healthy posture and prevent musculoskeletal diseases that can reduce the ability to carry various and/or excessive loads.

• Journal of Preventive Medicine and Public Health
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• v.35 no.1
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• pp.72-75
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• 2002

Objectives : To evaluate the health hazards in the underground storage facilities of ginger roots. Methods : The authors reviewed the emergency rescue records from the Seosan fire department over the period Jan 1, 1996 to Aug 31, 1999. The atmospheres in 3 different underground storage locations were analyzed for $O_2,\;CO_2,\;CO,\;H_2S\;and\;NH_4$. Results : From the emergency records, we were able to identify 20 individuals that had been exposed to occupational hazards in the underground storage facilities. Among these 20 cases, 13 were due to asphyxiation (resulting in f deaths) and 7 were due to falls. In the first atmospheric tests, peformed on Feb 25, 1998, the O2 level inside the underground storage facility, located about $5{\sim}6$ meters below the surface, was 20.6% and the $CO_2$ level was about 1,000 ppm. CO, $H_2S\;and\;NH_4$ were not detected. In the second tests on Jul 6, 1999, measurements of the $O_2$ level at 3 meters below the surface in two different storage locations were 15.3 and 15.1%. And the $O_2$ levels inside the storage facilities were 12.2 and 12.1%. The $CO_2$ level was above 5,000 ppm (beyond upper limits of measurement). CO, $H_2S\;and\;NH_4$ were not detected. Conclusions : We conclude that asphyxiation in the underground storage facilities for ginger roots was not due to the presence of toxic gases such as CO, $H_2S\;and\;NH_4$, but rather the exclusion of oxygen by carbon dioxide was responsible for causing casualties. For the development of a hazard free working environment, safety education as well as improvements in storage methods are needed.

• Molecular & Cellular Toxicology
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• v.4 no.4
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• pp.360-365
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• 2008

In the last several years, studies on the association of oxidative stress damage with exposure in the work place have been conducted. Xenobiotics create an imbalance of the homeostasis between oxidant molecules and antioxidant defense. By monitoring oxidative stress biomarkers, information was obtained on damages induced by oxidative stress and the toxicity of xenobiotics. In the present study, a Job Exposure Matrix (JEM) was constructed using the data from the Working Environment Measurement (WEM) of painters in the shipyard industry from the past 3 years to assess the exposure status. Additionally, by measuring the concentration of urinary malondialdehyde (MDA), the effect of lipid peroxidation was examined. The subjects consisted of 68 workers who were exposed to mixed organic solvents in the painting process and 25 non-exposure controls. The exposure indices of the exposure groups were significantly different (sprayer: 0.83, touchup: 0.54, assistant: 0.13, P<0.05). The urinary MDA concentration of the exposure group was 48.60${\pm}$ 39.23 ${\mu}mol$/mol creatinine, which was significantly higher than 18.03${\pm}$16.33 ${\mu}mol$/mol creatinine of the control group (P<0.05). From the multiple regression analysis of urinary MDA, the regression coefficient for exposure grade was statistically significant. In future studies, evaluation of the antioxidant levels of subjects should be performed simultaneously with quantitative exposure measurements.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.8
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• pp.419-428
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• 2017

In this study, energy loss due to ventilation load in the dock system was analyzed through simulation. Also, flow generated in the dock system of the warehouse was measured using manufactured measuring devices. Numerical simulation was conducted by simulating the most common picking tasks by examining the actual working environment. Incompressible and unsteady turbulent flows were assumed, and the turbulence model was the k-e standard model. Proper grid was selected through grid dependency test. Measurement was conducted using Honeywell and Vaisala sensors, and flow and temperature inside the warehouse were measured and compared with simulation results to validate simulation. When comparing amount of loss occurring in two hours and amount of loss occurring in 15 minutes, docking time of the former was eight times longer but energy loss was 3.8 times lower. Ventilation load occurring during the initial period after opening docking system accounted for a large proportion of total ventilation load. Also, comparing the load when the dock was closed and the load when the truck was parked, ventilation load was significantly higher than load due to heat conduction from the wall. Therefore, in improving the docking system, it is effective to reduce the gap by improving compatibility of the docking system and truck, rather than wall material.