• Proceedings of the KSR Conference
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• 2006.11b
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• pp.928-934
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• 2006

In this paper, the inductive power collector using electromagnetic induction for vehicle such as the electric railway vehicle system is suggested and some ideas for power collector design to improve the power transfer performance are presented. The inductive power of secondary part is related to amount of linked flux to secondary part by the length of air-gap, which is expected by such a system parameter as mutual inductance. This paper will study for the transfer characteristic of power from input to output and equation including mutual inductance.

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.1
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• pp.117-124
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• 2010

Different to other social infrastructures, bridge elements or bridges can be damaged or collapsed and this may cause death toll and severe social and economical damage, bridges should be managed to maintain a safety level. Diverse strengthening methods is developed to improve a deteriorated bridge performance up to original design level. But rational decision-making process and methodologies to select a optimum strengthening method are absence yet in Korea. This paper therefore derived items and proposed methodologies for quantity estimate considering uncertainty to select a optimum strengthening method among conceptually designed alternatives. And also, to demonstrate the applicability and verification of the proposed approach, it was applied to select the optimum strengthening method for the deteriorated T-shape concrete girder bridge. The model and the procedure can greatly contribute to the uncertainty-oriented alternative selection.

• Journal of the Korean Society for Railway
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• v.11 no.6
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• pp.569-574
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• 2008

Catenary and Pantograph are used to transmit electrical energy to electric railways. Catenary (Overhead Contact Lines) should be installed precisely and managed for stable train operations. But external factors such as weather, temperature, etc., or aging affect catenary geometry. Changed catenary stagger and height cause high voltage spark or instant electric contact loss. Big spark derived from contact loss can damage the pantograph carbon strip and overhead contact lines that might interrupt the train operations. Therefore, to prevent a big scale spark or electric contact loss, catenary maintenance are required catenary geometry measurement systems with catenary maintenance capability. In this paper, we describe the development of catenary height and stagger measurement system. The catenary height and stagger measurement system uses Acuity company's AR4000 Laser Range Finder for distance measurement and AccuRange Line Scanner for degree measurement. This system detects suspicious overhead line sections with excessive stagger and height stagger variance.

• Journal of Korean Society of Transportation
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• v.24 no.3 s.89
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• pp.85-94
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• 2006

Speeding is a critical issue related to safety. It is one of violations which result in high fatality regarding the crashes causing the death. It is also affected by driver s variables such as sex, age, or mileage. However, these demographic variables cannot only explain fully the psychological mechanisms of speeding but also they are not helpful for the traffic safety education. Therefore, in our study, focusing on the theory of planned behavior (TPB), we explored the effects of attitudes toward speeding as well as subjective norms and perceived behavioral control on the intention and behaviors of speeding in which the demographic variables were controlled. Moreover, because speeding can be habitual without driver s intention, we did hierarchical regression on Past behaviors or habit as variables with ought, anger, and impulse as Predictable variables. The result showed that it was significant that TPB variables predicted intention and behavior of speeding. In addition. all additional variables excepting ought and anger showed the significant increment of the explained variance. Consequently, the limitations and implications for the intervention program of speeding were discussed.

• Journal of the Korean Society of Safety
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• v.32 no.3
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• pp.74-82
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• 2017

This study was conducted to test the impacts of distractions caused by smartphones on pedestrians whilst walking alongside or across vehicular traffic in a high-density urban zone in South Korea. Through this study, we propose objective evidence for a link between the risk of traffic accidents and distractions from smartphones for pedestrians because of less likely notice activities surrounding road along their walking. This means that smartphones usage may cause inattentional blindness even during a simple activity that should require few cognitive resources. We conducted an experiment comparing pedestrian behavioral patterns of walking with smartphone distractions (such as listening to music with earphones or sending text messages) and normal walking without any distractions. In the experiment, participants walked along a pedestrian path prescribed by researchers and were observed at 8 points which were as follows: two observation points through which participants were instructed to listen to music whilst walking, two points where participants were instructed to send text messages, and four points through which participants were instructed not to use a smartphone at all. According to pedestrian behavior analysis, there is a trend for attention to be distributed amongst whatever other activities pedestrians are doing whilst walking. Therefore, this study proposes that pedestrians walking with such distractions are at a higher risk of traffic accidents compared to those who walk without such distractions. Thus, we advise for the South Korean government to consider ways to traffic policy that will enhance traffic safety for pedestrians.

• Journal of the Korea Convergence Society
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• v.6 no.6
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• pp.241-246
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• 2015

In cold winter season, the apparatuses of heating and heater which warm up the interior of a room are necessary element and the used amount of these apparatuses from the year 2000 has been increased abruptly. But, the fire accident and the danger of fire are also increased. Therefore, 3D modelling is done by referring three kinds of the electric heaters as the heaters of ceramic, carbon and near infrared ray sold in the city for the design of more safe heating apparatuses in this study. The thermal analyses with these models are carried out and the durabilities due to the thermal deformation and stress are studied. By the background of the study results derived in this study ultimately, the durabilities of electric heater models due to each shape can be anticipated and contributed to the development of new heating apparatus with more safe resistance to fire. And it is possible to be grafted onto the convergence technique at design and show the esthetic sense.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.1
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• pp.90-97
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• 2016

Sunken vessels accidents have harmful impacts on the marine environment because of oils and chemicals in the vessels. The government has managed them and developed risk assessment which can evaluate potential risk quantitatively since 1999. But the grades of present risk assessment has changed greatly depending on quantity of remaining fuel oils, and the list of remaining fuel oils omitted in status report of sunken vessels. Therefore, the aim of the study is to estimate and develop model for quantity of remaining fuel oils and verify the remaining fuel estimation comparison with active vessels. To accomplish the purpose of the study, apply this verified estimation model to current risk assessment and recommend guideline for an accurate sunken vessels risk assessment.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.12
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• pp.5464-5468
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• 2011

This paper deals with the development of the safety lancet and the electric lancing device. The safety lancet, in which a needle and a protective cap become one body, is designed. It is to prevent the secondary contamination by needlestick injury because the needle is always in the protective cap except for a moment of blood-gathering. The electric lancing device powered by batteries is devised to be operated by the moving rod of solenoid hitting the lancet. and to be used after selecting the repeat or the single hitting mode. The impact force by a hitting rod, the expected life of battery and etc. are measured for product development. This lancing device can be also used for the bloodletting device of the oriental medicine.

• Journal of the Korean Society for Nondestructive Testing
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• v.36 no.1
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• pp.45-52
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• 2016

Blast furnaces are crucial equipment for steel production. A typical furnace risks unexpected accidents caused by contraction and expansion of the walls under an environment of high temperature and pressure. In this study, an acoustic emission (AE) monitoring system was tested for evaluating the large-scale structural health of a blast furnace. Based on the growth of shell cracks with the emission of high energy levels, severe damage can be detected by monitoring increases in the AE energy parameter. Using this monitoring system, steel mill operators can establish a maintenance period, in which actual shell cracks can be verified by cross-checking the UT. From this study, we expect that AE systems permit early fault detection for structural health monitoring by establishing evaluation criteria based on the severity of shell cracking.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.5
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• pp.554-560
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• 2021

CRUD (chalk river unidentified deposits) is a porous material deposited on the surface of nuclear fuel during nuclear power plant operation. The CRUD is composed of metal oxides, such as iron, nickel, and chromium. It is essential to investigate the effects of the CRUD layer on the wall heat transfer between the nuclear fuel surface and the coolant in the event of a nuclear accident. CRUD only negatively affects the temperature of the nuclear fuel due to heat resistance because the effects of the CRUD layer on two-phase boiling heat transfer are not considered. In this study, the physical property models for the porous CRUD layer were developed and implemented into the SPACE code. The effects of boiling heat transfer models on the peak cladding temperature and quenching were investigated by simulating a reflood experiment. The calculation results showed some positive effects of the CRUD layer.