• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.14 no.6
• /
• pp.3052-3060
• /
• 2013

When planning to construct adjacent structure by the side tunnel, the criteria of safety zone of tunnel have been proposed. There are no specific theoretical basis regarding load conditions and the distance of structure and the geological strata and the conditions of adjacent structure's location, and the conditions applied load. Two and three dimensional numerical analysis preformed to prove the deformation of the ground and structures caused by the tunnel excavation and evaluated the correlation and the suitability of the tunnel's safety zone regarding the location of adjacent structures and the changes in the modulus of deformation. This paper proposed the safety zone's range is getting bigger as the modulus of deformation is higher. Also, it seems that the possible range of construction under constraints in the diagram of revalued safety zone significantly expands as shear failure line appears on the invert extension line below the spring line.

• Korean Chemical Engineering Research
• /
• v.46 no.1
• /
• pp.156-163
• /
• 2008

Process change and modification, which are caused by process failure, equipment life cycle and economic environment, have been generated in the chemical plants. And the MOC (management of change) base on the reasonable process safety technology such as change judgment, hazard identification by accurate technical references and risk assessment. But it is difficult to carry out the MOC because of lack of experience, shortage of knowledge and none of process safety specialists. In this study, the MOC system which could make enhancement of safety by finding and complementing weakness of MOC in chemical facilities was developed. This developed MOC system based on QRA was recommended the obvious standard for decision-making process, MOC procedure based on risk assessment and risk estimation of the process modification. The study based on the above way sought the enhancement of safety by performing Risk Based MOC for chemical plants.

• Journal of the Korean Institute of Gas
• /
• v.19 no.5
• /
• pp.36-40
• /
• 2015

To evaluate the safety of propane cylinder, the flame test was performed by the flame exposure scenario of propane cylinder. The cylinder which was exposed in a flame was rapidly occurred to increase the internal pressure by liquid expansion, if so it cause of physical explosion. Therefore, the cylinder which was applied with thermal pressure relief device sholud be not bursted and the propane should be discharged to outside safely. The flame average temperature that was around of cylinder is $600^{\circ}C$, and then it increased $700^{\circ}C$ by discharged propane. The result of flame test, the cylinder was deformed, but it was not bursted. The regulations of flame exposure test for propane cylinder were not restricted, this paper can be applied to restrict the flame test if the cylinder is possible to expose the flame. Also, the results is expected as reference for estimation of the pressure cylinder performance.

• Safety and Health at Work
• /
• v.1 no.1
• /
• pp.61-68
• /
• 2010

Objectives: The extent of the occupational cancer burden has rarely been estimated in Korea. The aim of this study is to provide an estimation of the population attributable fraction (PAF) of occupational cancer in Korea. Methods: Nine kinds of Group 1 carcinogens addressed by the International Agency for Research on Cancer (IARC) and 7 kinds of cancer were selected for the target carcinogens and diseases, respectively. The prevalence of carcinogen-exposed workers was estimated and correction factors were applied so that the value would be representative of the total population. Data on relative risk (RR) were taken from IARC reports and were compared with the RRs from the studies on Korean workers. The PAF was estimated according to Levin's formula. Results: The proportion of the general Korean population exposed to carcinogens was 9.7%. The PAF of total cancer was 1.1% for incident cancer cases and 1.7% for cancer deaths. The PAFs of lung cancer and leukemia were 7.0% and 4.5%, respectively. With the RRs reported from Korean studies, the PAF for lung cancer and leukemia were 3.7% and 3.4%, respectively. Conclusion: The PAF in this study (1.1%) was lower than that reported in previous studies (2-4%) from developed countries. Considering that only 9 of the 29 kinds of Group 1 carcinogens were included in this study, the PAF might be underestimated. However, because the process of industrialization in Korea differs from that which occurred in other developed countries, 1.1% of the PAF might be appropriate for Korea.

• Food Science and Preservation
• /
• v.30 no.4
• /
• pp.573-588
• /
• 2023

The purpose of this study was to monitor changes in the quality of ginseng and predict its shelf-life. As the storage period of ginseng increased, some quality indicators, such as water-soluble pectin (WSP), CDTA-soluble pectin (CSP), cellulose, weight loss, and microbial growth increased, while others (Na₂CO₃-soluble pectin/NSP, hemicellulose, starch, and firmness) decreased. Principal component analysis (PCA) was performed using the quality attribute data and the principal component 1 (PC1) scores extracted from the PCA results were applied to the multivariate analysis. The reaction rate at different temperatures and the temperature dependence of the reaction rate were determined using kinetic and Arrhenius models, respectively. Among the kinetic models, zeroth-order models with cellulose and a PC1 score provided an adequate fit for reaction rate estimation. Hence, the prediction model was constructed by applying the cellulose and PC1 scores to the zeroth-order kinetic and Arrhenius models. The prediction model with PC1 score showed higher R² values (0.877-0.919) than those of cellulose (0.797-0.863), indicating that multivariate analysis using PC1 score is more accurate for the shelf-life prediction of ginseng. The predicted shelf-life using the multivariate accelerated shelf-life test at 5, 20, and 35℃ was 40, 16, and 7 days, respectively.

• Proceedings of KOSOMES biannual meeting
• /
• 2018.06a
• /
• pp.154-154
• /
• 2018

• Proceedings of KOSOMES biannual meeting
• /
• 2018.06a
• /
• pp.177-177
• /
• 2018

• Proceedings of the KSME Conference
• /
• 2001.11b
• /
• pp.824-829
• /
• 2001

The main objective of the study is to provide the criteria for determining the proper life cycle of rebuiled diesel-electric locomotive currently being operated in KNR. We predicted the most critical sections of the underframes and tested the diesel-electric locomotive vehicle to measure dynamic stresses applied to the underframes. The fileld test of the diesel-electric locomotive estimated 17.08years based on the fatigue-life estimation when they are continuously used in the present operation condition.

• Proceedings of the KSR Conference
• /
• 2001.10a
• /
• pp.240-246
• /
• 2001

The main objective of the study is to provide the criteria for determining the proper life cycle of rebuiled diesel-electric locomotive currently being operated in KNR. We predicted the most critical sections of the cast-iron bogie and tested the diesel-electric locomotive vehicle to measure dynamic stresses applied to the bogie. The fileld test of the diesel-electric locomotive estimated 9.90years based on the fatigue-life estimation when they are continuously used in the present operation condition.

• Proceedings of the KSR Conference
• /
• 2005.05a
• /
• pp.123-126
• /
• 2005

Recently many accidents have been occurred on track workers, these accidents have strong relationship with increase of train speed, electrification and multiple track portion. As a first step for the safety management, domestic and abroad track worker accidents data are analysed for the risk estimation of track worker. Analysis results shows that contact between track worker and train is the dormant reason. In order to reduce dormant reason fault trees are constructed in this study.