• Journal of Korean Tunnelling and Underground Space Association
• /
• v.22 no.1
• /
• pp.107-120
• /
• 2020

In a performance-based evaluation of structures in use, the current performance is assessed by summing up the weighting of the evaluation indices for each performance. In this study, to suggest a performance-based evaluation technique for NATM tunnels in use, the performance evaluation indices were derived by examining the characteristics and similarities of each index developed from previous study. The weighting of the evaluation indices was derived by calculating the relative importance of each evaluation indices from the AHP analysis. In order to develop a quantitative evaluation model, grading criteria for each performance index was derived through literature review, and performance evaluation tables for road and railway tunnels were presented. In order to verify the significance of the proposed performance evaluation model, the correlation analysis was performed between each evaluation index and the final evaluation result. In the correlation analysis, the survey data measured through precision safety diagnosis in the tunnel in use was applied. It may be said that the proposed evaluation indices, weighting, criteria and evaluation models for tunnels in use can be applied to the performance-based maintenance system of tunnels.

• Proceedings of the Safety Management and Science Conference
• /
• 2008.11a
• /
• pp.681-692
• /
• 2008

• Journal of the Korean Society of Safety
• /
• v.18 no.1
• /
• pp.64-70
• /
• 2003

For the unconfined vapor cloud explosion(UVCE) accident by the continuous release of gas-liquid flow of various saturated liquids in a vessel at ground level, overpressures were estimated by TNT equivalency model with two estimation methods, such as UVCE I model based on a constant release time and UVCEII model based on a real travel time of vapor by dispersion and analyzed with various release conditions. As a simulation result the simple, easy, and correct method of evaluation of consequences of the UVCE accident was proposed by using consequences of UVCE I model and correlation equations for differences of overpressures between UVCE models, so that this evaluation method could be used easily in the small and medium size enterprises without using the dispersion model.

• Proceedings of the Safety Management and Science Conference
• /
• 2002.05a
• /
• pp.91-97
• /
• 2002

In this thesis presents line balancing problems of two-sided and mixed model assembly line widely used in practical fields using genetic algorithm for reducing throughput time, cost of tools and fixtures and improving flexibility of assembly lines. Two-sided and mixed model assembly line is a special type of production line where variety of product similar in product characteristics are assembled in both sides. This thesis proposes the genetic algorithm adequate to each step in tow-sided and mixed model assembly line with suitable presentation, individual, evaluation function, selection and genetic parameter. To confirm proposed genetic algorithm, we apply to increase the number of tasks in case study. And for evaluation the performance of proposed genetic algorithm, we compare to existing algorithm of one-sided and mixed model assembly line. The results show that the algorithm is outstanding in the problems with a larger number of stations or larger number of tasks.

• Journal of the Korea Safety Management & Science
• /
• v.4 no.2
• /
• pp.83-101
• /
• 2002

In this thesis presents line balancing problems of two-sided and mixed model assembly line widely used in practical fields using genetic algorithm for reducing throughput time, cost of tools and fixtures and improving flexibility of assembly lines. Two-sided and mixed model assembly line is a special type of production line where variety of product similar in product characteristics are assembled in both sides. This thesis proposes the genetic algorithm adequate to each step in tow-sided and mixed model assembly line with suitable presentation, individual, evaluation function, selection and genetic parameter. To confirm proposed genetic algorithm, we apply to increase the number of tasks in case study. And for evaluation the performance of proposed genetic algorithm, we compare to existing algorithm of one-sided and mixed model assembly line. The results show that the algorithm is outstanding in the problems with a larger number of stations or larger number of tasks.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
• /
• 1997.11a
• /
• pp.384-391
• /
• 1997

The hazard assessment in which the potential hazard factors In the buildings are investigated and the scale of the hazard is analyzed should be performed first in order to prevent personal and material damages due to building fire. In this study, the building fire hazard are assessed using 822-item checklist, for the qualitative evaluation of which the main factors are classified into 10 items, yielding 100 scale points with some weighting. It is shown that present model is applicable for the assessment of all general buildings through the examination of the suitability of assessment model by actual assessment of existing building. Also, the checklist is prepared in itemized questionnaire form for easy assessment of building fire hazard. Therefore, the present model will be helpful for those working in fire prevention, who are suffering from the lack of manifest evaluation model for the fire prevention assessment so far in Korea.

• YAKHAK HOEJI
• /
• v.58 no.4
• /
• pp.255-261
• /
• 2014

Poly-pharmacy has been on the rise because of aging of population and chronic disease. Most of drug metabolism happens in the liver by CYP isozymes and the metabolism by CYP450 enzymes. The Cytochrome P450 (CYP) is a superfamily of enzymes that catalyzes the oxidations of many endogenous and exogenous compounds. Primary human Hepatocytes (HH) are considered as the gold standard model for In vitro drug interaction studies. However, there are several limitations (cost, limited life span) for using HH cells. HepaRG cells are being used as a possible alternative. HepaRG cells were cultured in William E medium containing the positive control inducers (1A2: 10, 25, 50 ${\mu}M$ omeprazole, 2C9 and 2C19: 10 ${\mu}M$ rifampin, 3A4: 10, 25, 50 ${\mu}M$ rifampin) at $37^{\circ}C$, 5 % $CO_2$ in a humidified atmosphere. This study was to evaluate the induction of CYP isozymes (1A2, 2C9, 2C19 and 3A4) using LC-MS/MS. We evaluated the potential induction ability of Bosentan, as a drug of pulmonary artery hypertension, in HepaRG cells. For reference, dose of the Bosentan is determined to the basis of the $C_{max}$ (835 mg/ml) value. The enzyme activity demonstrated that CYP2C9 and 3A4 were induced up to 20 times by Bosentan. Like as In vivo, the enzyme activity of CYP2C9 and CYP3A4 is significantly induced in a dose-dependent by Bosentan.

• Journal of the Korean Society of Safety
• /
• v.35 no.6
• /
• pp.54-60
• /
• 2020

Recently, the issue of construction safety is growing. In the construction industry, accidents have continued to increase since 2000. In particular, the number of accident deaths at small and medium-sized construction sites accounts for 72.11% of the total number of accident deaths in the construction industry. For construction safety, prior safety evaluation systems such as Design for safety and safety management plan preparation are in place. However, at construction sites, these systems are recognized as formal legal documents, and their effectiveness is greatly reduced. Therefore, in this study, a linkage model that links design safety review information and safety management plan information was presented so that the safety management plan can be efficiently established. In addition, the effectiveness of the proposed process was verified as an example of actual work. The linkage model will contribute to improving the safety management environment at the site by increasing the productivity of safety management work by enabling easy sharing of risk factor information in the construction stage safety management work. The results of this study will be used as basic information for the development of the integrated safety management system.

• Geomechanics and Engineering
• /
• v.30 no.3
• /
• pp.313-324
• /
• 2022

With the development of the economy, people's utilization of underground space are also improved, and a large number of cities have begun to build subways to relieve traffic pressure. The choice of subway station construction method is crucial. If an inappropriate construction method is selected, it will not only waste costs but also cause excessive deformation that may also threaten construction safety. In this paper, a subway station construction scheme selects model based on the AHP-fuzzy comprehensive evaluation. The rationality of the model is verified using numerical simulation and monitoring measurement data. Firstly, considering the economy and safety, a comprehensive evaluation system is established by selecting several indicators. Then, the analytic hierarchy process is used to determine the weight of the evaluation index, and the dimensionless membership in the fuzzy comprehensive evaluation method is used to evaluate the advantages and disadvantages of the construction method. Finally, the method is applied to Liaoyang east road station of Qingdao metro Line 2, and the results are verified by numerical simulation and monitoring measurement data. The results show that the model is scientific, practical and applicable.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.10 no.8
• /
• pp.1435-1442
• /
• 2006

The ideal method of safety evaluation is to verify results of execution against all possible operations within operating system, but it is impossible. However, the formal method can theoretically prove the safety on actual logic of operating system. Therefore we explain the contents of the art of the safety verification of security kernel, and make a comparative study of various standardized formal verification tools. And then we assigned PVS(Prototype Verification system) of SRI(Stanford Research Institute) to verify the safety of a modified BLP(Bell & LaPadula) model, the core access control model of multi-lavel based security kernel. Finally, we describe formal specification of the revised BLP model using the PVS, and evaluate the safety of the model by inspecting the specification of the PVS.