• Journal of the Korean Society of Safety
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• v.22 no.6
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• pp.46-54
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• 2007

The purpose of this study was to examines the burning rate of fire retardant treated wood in the cone heater with a one-dimensional integral model. The wood samples used in this study were four species. The species of woods are Redwood, White oak, Douglas fir and Maple. Each sample was nominally 50mm thick and 100mm square. Samples were exposed to a range of incident heat fluxes 10 to $35kW/m^2$ using the cone heater. A one-dimension integral model has been used to predict burning rate, heat of gasification, flame heat fluxes, charring rate and char depth of samples. As a result measurement of mass loss rate, softwoods(Redwood and Douglas fir) has relatively low value than those for hardwoods(White oak and Maple). Average charring rate of woods in case of fire retardant treatment showed reduction effect of 41.29%, 50.00%, 48.18% and 60.82% for Redwood, Douglas fir, White fir and Maple, respectively. Almost all the predictions from integral model showed faster charring than those measured. Average difference between predictions and experimental data was 16%, 9.5% and 11.8% for N, F1 and F2 respectively. Water-soluble fire retardant used in this study find out more effect in hardwood than softwood from the result of measurement of mass loss rate and average charring rate.

• Journal of the Korean Society of Safety
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• v.32 no.3
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• pp.151-159
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• 2017

This study deals with characteristics and risk of a PM based on user survey result, road driving test and data analysis of PM accident. Text mining method is applied to extract PM accident data from Big Data, which are claim data of private insurance company. Road driving test and survey on safety, convenience, noise, overtake ability, steering ability, and climbing ability of PM are performed to evaluate user's safety and convenience considering domestic road condition. As the result of claim data analysis, annual average increase rate of PM accident is 47.4% and average compensation of personal mobility is higher than that of bicycle by maximum 1.5 times. 79.8% of PM accident is self-caused accident due to unskilled driving and age-specific diagnosis rate of driver over 60 is higher than that of under 60. Diagnosis rate of over 60 at lower limb, foot, rib and spine is especially higher than that of under 60. As the result of road driving test and user survey, satisfaction level on safety and convenience of PM is evaluated as close to that of bicycle and satisfaction level of PM is increased after boarding. Overtake ability, steering ability, and climbing ability of PM are evaluated as same or better than that of bicycle but warning equipment to pedestrian or bike such as horn is required because noise level of PM during driving is too low. Finally, user survey result shows that bicycle road is suitable for PM and safety standard, advance-education and insurance are required for PM. It is suggested that drivers' license for PM can be replaced by advance-education. Results of this study can be used to prepare safety measures and legal basis for PM operation.

• Journal of Korean Society on Water Environment
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• v.30 no.3
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• pp.351-360
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• 2014

The allocation of margin of safety (MOS) at a uniform rate to all areas of the unit watershed makes it very difficult to keep the load allotment stable in the area for lack of reduction measures like forest land. This study developed an equation to calculate margin of safety differentially according to the regional characteristics. The equation was formulated on the basis of the regional characteristic factors such as a load contribution factor for land use type and a site conversion factor for the unit watershed. The load contribution factor represents a contribution of loads from a particular land use. The site conversion factor was derived from the site conversion ratio of a unit watershed. Margin of safety for the non-point pollution load in the land use sector decreased by 20~25% in three river basins. The margin of safety in the unit watersheds with low site occupation ratios decreased in high rate, while in the unit watersheds with large urban area decreased in low rate. With the application of the differential margin of safety considering regional characteristics, not only the reduction of pollution loads can become lighter but also it can be easier to develop plans for Total Maximum Daily Loads (TMDLs) even where the reduction measures are not available.

• Korean Journal of Construction Engineering and Management
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• v.12 no.6
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• pp.3-13
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• 2011

The construction industry is still the most risky industry and labor accident is a significant management factor on construction site. Safety management has been studied for improving the safety performance on construction sites. However, Almost all of them have been considered on the site safety management for the contractors and evaluation of accident rate. To resolve the limitation of current research, this study is focused on considering accident result and effort by performing the evaluation of safety level of the head office and site in construction companies. By studying the research about a safety management and interviewing with specialists in safety management, 7 items were selected and weighted based on the KOSHA18001 List. Consequently, The checklist was developed to evaluate safety performance management in construction company and Safety Management Index was suggested to coordinate 1) the score of results in accident rate and 2) the effort to evaluate a safety performance management. Safety Management Index is more helpful to evaluate the safety management results and effort. As a result of considering the score of the accident rate and the safety performance management, the outcome of prequalification was changed. Using this index, contractors will attempt to prevent accidents and owners will be able to discriminate individual differences in bidding process.

• Safety and Health at Work
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• v.2 no.1
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• pp.26-33
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• 2011

Objectives: The purpose of this retrospective cohort study was to investigate the relationship between exposure of Korean workers to petrochemicals in the refinery/petrochemical industry and lymphohematopoietic cancers. Methods: The cohort consisted of 8,866 male workers who had worked from the 1960s to 2007 at one refinery and six petrochemical companies located in a refinery/petrochemical complex in Korea that produce benzene or use benzene as a raw material. Standardized mortality ratios (SMRs) and standardized incidence ratios (SIRs) were calculated for 1992-2007 and 1997-2005 based on the death rate and cancer incidence rate of the Korean male population according to job title (production, maintenance, laboratory, and office workers). Results: The overall mortality and most cause-specific mortalities were lower among these workers than those of the general Korean population. Increased SMRs were observed for leukemia (4/1.45; SMR 2.77, 95% CI: 0.75-7.09) and lymphohematopoietic cancers (5/2.51; SMR 2, 95% CI: 0.65-4.66) in production workers, and increased SIRs were also observed in leukemia (3/1.34; SIR 2.24, 95% CI: 0.46-6.54) and lymphohematopoietic cancers (5/3.39; SIR 1.47, 95% CI: 0.48-3.44) in production workers, but the results were not statistically significant. Conclusion: The results showed a potential relationship between leukemia and lymphohematopoietic cancers and exposure to benzene in refinery/petrochemical complex workers. This study yielded limited results due to a short observational period; therefore, a follow-up study must be performed to elucidate the relationship between petrochemical exposure and cancer rates.

• Transactions of the Korean hydrogen and new energy society
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• v.28 no.6
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• pp.675-682
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• 2017

New government, the market for stationary fuel cell systems in domestic is expected to expand in line with the policy for expanding new and renewable energy. In order to promote and expand the domestic market for stationary fuel cell systems, it is required to do research and develop for cost reduction and efficiency improvement technologies through the localization of BOP. In this study, the safety performance including the power consumption, flow rate, noise and air-tightness of the domestic fuel booster blower and the foreign fuel booster blower was evaluated and the performance improvement of the domestic blower was confirmed. As a result of the power consumption measurement and the flow rate according to the back pressure of the A company 2nd prototype and B company, the values were 73 W, 27 LPM, and 55 W, 25 LPM. These results are attributed to the improvement of performance through design changes such as CAM angle and diaphragm material.

• Journal of the Korea Safety Management & Science
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• v.11 no.4
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• pp.261-267
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• 2009

The purposes of this article is to analyse how market competition of credit card company affect price(interest rate) and survival length of card users. This paper uses individual account data from a large Korean credit card company during the periods from 2002 to 2006. The findings of our study are as follows. First, market competition of credit card company have a negative effect with interest rate of credit card. Second, market competition of credit card company have a affirmative effect with survival length. Finally, The effect of Increasing delinquency rate due to price increase is smaller than decreasing delinquency rate due to extending survival length.

• Journal of Food Hygiene and Safety
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• v.12 no.4
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• pp.340-345
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• 1997

This study was undertaken to evaluate microbial risk degree of some processed foods in Korea. In this study the data on the outbreak of foodborne diseases during recent 18 years (1976-1989, 1993-1996. 8) were analyzed. The most frequently isolated pathogens were Salmonella (36.9%); followed vibrio (22.0%), Staphylococcus (15.7%) and Escherichia coli (13.3%). Outbreak rate of Staphylococcus, Vibrio, E. coli and Salmonella, was 33.0%, 23.5%, 17.5% and 17.1%, respectively. Overall risk degree of pathogens by fatality rate, outbreak rate and pathogen amount for foodborne outbreak was Clostridium, 5, Staphylococcus and Vibrio, 4, Salmonella and E. coli, 3. Based on foodborne pathogens, the risk degree of raw seafoods, raw eggs and processed seafoods were 4, and those of raw meats, Doshiraks and milk products were 3. Also, based on processing characteristics of foods, the risk degree of surimi-based imitation crab was 3. Foods of the highest actual risk degree were raw seafoods and raw eggs (16); followed raw meats (15), surimi-based imitation crab (12), Doshirak (9) and milk products (6).

• Journal of the Korean Society of Safety
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• v.14 no.4
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• pp.176-181
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• 1999

The objective of this study is to compare and analyze the industrial injury-values of all the industries through yearly accident rate and frequency rate based on the governmental documentation of industrial injuries. The samples for this study are chosen from the companies with less than 200 employees under charge of the Kangnung Ministry of Labor during the period of 1995-97. Safe-T-Score is used for statistic control on the qualitative comparison of the present and the past industrial injury-rates. In the comparison of the past and the present industrial injury-rate by means of Safe-T-Score, this study shows that there does not exist any remarkable improvement, whereas the document of the Ministry of labor reports that the rate is decreasing greatly. Therefore, this study proposes some solutions to reduce industrial disasters and points out the necessity of more practical and effective methods to analyze the industrial disaster.

• Journal of the Korean Society of Safety
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• v.5 no.2
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• pp.58-65
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• 1990

The purpose of this study is to consider the effects of strain rate on the stress-strain behavior of sheet metal at instability. The results and conclusions obtained as follows ： 1. As the strain rate increases, the fracture pressure increases and the polar height at fracture decreases. 2. The effect of strain rate on forming limit diagram produces a general lowering of the diagram with increasing strain rate but changes according to materials and strain paths. 3. The forming limit diagram predicted by swift instability theory is comparatively inconsistent with the experimental result at high strain rates, because there is inevitable gap between them.