• Journal of the Computational Structural Engineering Institute of Korea
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• v.28 no.3
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• pp.241-248
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• 2015

There are a lot of equipment related to safety and electric power production in nuclear power plants. The structure and equipment in NPPs were generally designed considering a high safety factor to remain in the elastic zone under earthquake load. However it is needed to revaluate the seismic capacity of the structure and equipment as the magnitude of earthquake was recently increased. In this study the floor response due to the nonlinear behaviors of structure was analyzed and the inelastic structural response factor was calculated by the nonlinear time history analysis. The inelastic structural response factor was calculated by the EPRI method and the nonlinear analysis method to realistically evaluate the seismic fragility for the equipment. According to the analysis result, it was represented that the inelastic structural response factor was affected by the natural frequency of equipment, the location of equipment and the dynamic property of structure.

• Journal of the Korean Society of Safety
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• v.32 no.1
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• pp.9-14
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• 2017

Diffusion bonding is a technique that has the ability to join materials with minimum change in joint micro-structure and deformation of the component. The quality of the joints produced was examined by metallurgical characterization and the joint micro-structure developed across the diffusion bonding was related to changes in mechanical properties as a function of the bonding time. An increase in bonding time also resulted in an increase in the micro-hardness of the joint interface from 55 VHN to 180 VHN, The increase in hardness was attributed to the formation of intermetallic compounds which increased in concentration as bonding time increased.

• International Journal of Highway Engineering
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• v.19 no.6
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• pp.117-127
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• 2017

PURPOSES : The objective of this research is establishing system components and optimizing operational procedures in order to systematically manage road cave-ins in urban areas. METHODS : Based on the literature review and alternative comparison, optimization methods is suggested. RESULTS : Throughout the study, location referencing system, database structure, and operation strategy(procedure) were clarified, and the optimization methods for each item were suggested. CONCLUSIONS : Road cave-in management should be focused on user safety rather than focusing on economic aspects. The occurrence of road cave-in should be addressed thoroughly by road management system(location referencing system, database structure, and operation strategy(procedure), and the optimization methods), since they are closely related to road users' safety.

• YAKHAK HOEJI
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• v.58 no.1
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• pp.53-57
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• 2014

In recent, the abuse of newly-emerging psychoactive drugs, ('designer drugs') is a rapidly increasing problem in Korean society. Quantitative-structure activity relationship (QSAR) is an alternative method to predict bioactivities of new abused compounds. In this study, cathinone-related new designer drugs, 4-methylbuphedrone and 4-methoxy-N,N-dimethylcathinone were tested for prediction of the bioactivity with QSAR model. The bioactivity of 4-methylbuphedrone and 4-methoxy-N,N-dimethylcathinone was similar to those of methylone. These results suggest that the prediction with QSAR model may provide scientific evidences for regulatory decision.

• Korean Journal of Health Education and Promotion
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• v.18 no.1
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• pp.127-137
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• 2001

The study of home injury and injury prevention has been a neglected area of research and practice. This study has the following purposes: 1) to describe the pattern of home injuries; 2) to analyze the differences in injuries by social characteristics; and 3) to compare the impact of safety structure and action. The data were collected by person-to-person interviews with 450 residents living in Wonju area. The statistical methods used for the analysis were $\chi$2-test and multiple logistic regression. The results are as follows: 1) Whether or not a certain injury has occurred varies by household type. The elderly household reported more injuries than other types of household. 2) Using logistic regression method, we found that safety-related behavioral habit was statistically significant in predicting injury occurrence. However, residence type was not a statistically significant variable. This indicates that cognitive change strategy is more important than structural change strategy.

• Journal of the Korean Society of Systems Engineering
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• v.20 no.spc1
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• pp.108-118
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• 2024

As shared electric kick scooters spread to cities worldwide as a result of the proliferation of personal mobility, they have emerged as a significant social issue, impacting pedestrian and user safety, as well as urban aesthetics. In this study, we propose solutions to the unique problems associated with shared electric kick scooters, such as illegal parking, charging, and redistribution. Furthermore, we present research on supplementary services utilizing electric kick scooters in urban areas to enhance citizen safety and user satisfaction through the development of an autonomous electric kick scooter system structure and operational strategies. We suggest a low-cost autonomous electric kick scooter structure and propose AI processing, sensor fusion, and system operation methods to add autonomous capabilities to affordable electric kick scooters. Additionally, we propose operational systems and related technologies for offering various supplementary services.

• Journal of the Korean Society of Safety
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• v.35 no.4
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• pp.64-73
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• 2020

As Korean government and safety-related organizations make continuous efforts to reduce the number of industrial accidents, accident rate has steadily declined since 2010, thereby recording 0.48% in 2017. However, the number of fatalities due to industrial accidents was 1,987 in 2017, which means that more efforts should be made to reduce the number of industrial accidents. As an essential activity for enhancing the system safety, accident analysis can be effectively used for reducing the number of industrial accidents. Accident analysis aims to understand the process of an accident scenario and to identify the plausible causes of the accident. Accident analysis offers useful information for developing measures for preventing the recurrence of an accident or its similar accidents. However, it seems that the current practice of accident analysis in Korean manufacturing companies takes a simplistic accident model, which is based on a linear and deterministic cause-effect relation. Considering the actual complexities underlying accidents, this would be problematic; it could be more significant in the case of human error-related accidents. Accordingly, it is necessary to use a more elaborated accident model for addressing the complexity and nature of human-error related accidents more systematically. Regarding this, HFACS(Human Factors Analysis and Classification System) can be a viable accident analysis method. It is based on the Swiss cheese model and offers a range of causal factors of a human error-related accident, some of which can be judged as the plausible causes of an accident. HFACS has been widely used in several work domains(e.g. aviation and rail industry) and can be effectively used in Korean industries. However, as HFACS was originally developed in aviation industry, the taxonomy of causal factors may not be easily applied to accidents in Korean industries, particularly manufacturing companies. In addition, the typical characteristics of Korean industries need to be reflected as well. With this issue in mind, we developed HFACS-K as a method for analyzing accidents happening in Korean industries. This paper reports the process of developing HFACS-K, the structure and contents of HFACS-K, and a case study for demonstrating its usefulness.

• Journal of the Earthquake Engineering Society of Korea
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• v.22 no.3
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• pp.169-174
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• 2018

A total of 594 reservoirs (17%), which are managed by KRC, equipped with earthquake-resistant facilities whereas remaining ones did not. In addition, reservoirs were placed without the effect of geological structures (i.e., fault and lineament). Therefore, development on technique for alleviating the potential hazards by natural disasters along faults and lineaments has required. In addition, an effective reinforcement guideline related to the geological vulnerabilities around reservoirs has required. The final goal of this study is to suggest the effective maintenance for the safety of earth fill dams. A radius 2 km, based on the center of the reservoir in the study area was set as the range of vulnerability impacts of each reservoir. Seismic design, precise safety diagnosis, seismic influence and geological structure were analyzed for the influence range of each reservoir. To classify the vulnerability of geological disasters according to the fault distribution around the reservoir, evaluation index of seismic performance, precise safety diagnosis, seismic influence and geological structure were also developed for each reservoir, which were a component of the vulnerability assessment of geological disasters. As a result, the reservoir with the highest vulnerability to geological disasters in the pilot district was analyzed as Kidong reservoir with an evaluation index of 0.364. Within the radius of 100km from the epicenter of the Pohang earthquake, the number of agricultural infrastructure facilities subject to urgent inspections were 1,180 including reservoirs, pumping stations and intakes. Four reservoirs were directly damaged by earthquake among 724 agricultural reservoirs. As a result of the precise inspection and electrical resistivity survey of the reservoir after the earthquake, it was reported that cracks on the crest of reservoirs were not a cause of concern. However, we are constantly monitoring the safety of agricultural facilities by Pohang aftershocks.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.1370-1378
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• 2007

High speed railway bridge is affected on safety of bridge by dynamic amplification effect, when dynamic response of bridge is equal to effect cycle load for rolling stock axle according to high speed operation train. And excessive deformation of structure has negative effect on operation safety of train and comfort of passenger due to fluctuation of wheel load by torsion of track etc. and decrease of contact force on vehicle wheel-rail. To ensure the safety of track and train operation safety, it is have to perform the study on resonance and deformation of structure. That criteria and requirement of railway bridge is limitation of vertical acceleration on deck for dynamic behavior of structure, contact of vehicle wheel and rail, limitation of face distortion and rotation angle of end deck, and limitation of vertical displacement by train. Unlike KYEONGBU High Speed Railway, New constructed HONAM High Speed Railway have to applied the new requirement for dynamic behavior safety according to change of condition which is type of ballast (slab ballast), interval of track, and actual rolling stock load. Therefore, in this paper, it was conformed the dynamic characteristic due to parameter, which related with above mentioned criteria, for steel composite bridges.

• Hwankyungkyoyuk
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• v.22 no.1
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• pp.97-109
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• 2009

The purpose of this study is to grasp the degree of recognition of the ESD(Education for Sustainable Development) form Technology Home Economic teachers in high schools, to analyze contents related to the ESD within the textbooks, and to propose the improvement method of the textbooks. As a result, first, the degree of recognition on the ESD was less than about 30.1% in Technology Home Economic teachers. Second, the content and factor criterions for the ESD were developed on the basis of the previous studies. They are suitable for applying to the Vehicle Chapter in the textbooks and are including 9 contents and 7 factors, respectively. Third, the contents related to the ESD within a Technology. Home Economic textbook showed 36.1% in Technology, 33.8% in Home Economics including social and cultural(44.7%), environmental(47.1%), and economic contents(8.2%). But they in the Vehicle Chapter within the textbooks presented 69.1%, 4.8%, 26.1% in social and cultural, environmental, and economic contents, respectively. Finally, the improvement method of the new textbook for the Vehicle Chapter is to adopt issued factors including the suitable adjustment on the vehicle structure and safety as well as the supplement of environmental contents related to the ESD. In addition, it is necessary to contain the contents such as the developing process of environment-friendly vehicles, the economically sustainable consumption strategy, and the cause-and-effect relationship with the global warming in the new textbook.