• Proceedings of the KSR Conference
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• 2004.10a
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• pp.1419-1424
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• 2004

Railway safety is based on a risk analysis and safety assessment for the whole railway system as human, train, electric, signaling, operation, maintenance and etc. Therefore in this study, after investigating the accidents happened in electric railway on Choongang line for 5 years, from '97 to '01, a Data-Base was made through a cause and result analysis. In consideration of economic loss and human resources damage, a risk assessment for electric railway was also performed.

• Journal of the Korean Society of Marine Environment & Safety
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• v.13 no.1 s.28
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• pp.55-60
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• 2007

Many electric power cables span the sea in Korean archipelago. Lots of shipping routes were established between the islands in the same area and ships frequently sail under the cable which cross the seas. Sometimes electric power cables were accidently broken by sailing ships and catastrophic damage of island industry followed thereby. If navigators have detailed knowledge about the height of electric power cable, the ship's sailing condition will be greatly improved. But at the present time, navigators have limited data about the electric power cable. Those are the horizontal distance between pylons, the height of pylons and minimum height of electric power cable. This study introduced the calculating methodology to find out the height of cable at any position between pylons. The ship's tracks were recorded and traffic safety was assessed by statistical method in relation to cable height.

• Transactions of the Korean Society of Automotive Engineers
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• v.24 no.6
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• pp.635-641
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• 2016

Regenerative braking performance of an electrically powered vehicle is closely related to driving distance per battery charge. An electric vehicle uses appropriate amounts of mechanical braking force and electromagnetic regenerative braking force to recover energy and increase driving efficiency. In particular, when it drives on a downhill road, energy recovery rate is maximized through regenerative braking during coasting based on the mass inertia of the vehicle. Since an electric two-wheeled vehicle covered in this paper is lighter than an electric four-wheeled vehicle, the improvement of its driving distance per battery charge through regenerative braking is different from an electric four-wheeled vehicle. This study compared the driving characteristics of an electric two-wheeled vehicle based on regenerative braking. Two driving test modes were simulated with a chassis dynamometer system. By analyzing the measurement of a chassis dynamometer, the driving characteristics of a two-wheel electric vehicle, such as driving efficiency, were analyzed. In addition, test results were reviewed to draw the limitations of conventional test methods for regenerative braking performance of an electric two-wheel vehicle.

• Journal of the Society of Disaster Information
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• v.20 no.1
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• pp.32-39
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• 2024

Purpose and Method: This study aims to suggest institutional improvements to enhance the response to electric vehicle fires. To this end, we examined the prevalence of electric vehicles, fires, and related legal systems in Seoul. Results: The top-level laws and ordinances related to electric vehicles are centered on distribution policies, so there is no practical fire response plan for electric vehicle fires. In order to apply the same regulations to each local government, it is necessary to set standards and establish a system for firefighting and safety facilities in higher laws. Conclusion: Establishing standards for the installation of fire and safety facilities that take into account the characteristics of electric vehicle fires and improving related systems will ultimately lead to an increase in the penetration rate of electric vehicles.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.838-843
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• 2006

In our modern society, such electric facilities as lighting, elevators, water supplies, drainages, waste water treatments and landscape lighting are being more enlarged, diversified and technology-intensive owing to outstanding technological development, while they require reliable and safe electricity. On the other hand, as more electric energy is consumed with more complicated systems operated, any accident from a personal electric system is likely to have wider spreading effects. In particular, the electric receivers and transformers installed for such public facilities as subway stations require highest safety, reliability and economy, but such requirements tend to be less considered than such financial requirements as budget conditions, much less their safety and reliability. In such a circumstance, this study was aimed at suggesting some standards for safe, reliable and economic subway electric systems in terms of their scale, location and uses. Specifically, this study put forwards the ways to optimize and standardize the electric systems including receivers and transformers for subway stations in order to make them safer, more reliable and economic.

• Journal of Auto-vehicle Safety Association
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• v.15 no.4
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• pp.32-38
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• 2023

With the transition from internal combustion engine vehicles to eco-friendly cars, it has become essential to systematically construct an education system for electric vehicles based on high-voltage electric devices. In this study, we discussed the establishment of an educational system for electric vehicles based on high-voltage electric devices and proposed methods for qualifications after completing the education. To ensure systematic education, we presented a classification of learners according to their levels and job competencies. Additionally, we emphasized the importance of providing adequate practical training equipment for courses that require higher qualifications. Finally, to distinguish between the levels of completion of training and practical skills, we highlighted the necessity of implementing a system to certificates to individuals who have successfully completed the systematic training program.

• 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.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.12
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• pp.2113-2118
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• 2016

The precise detection of electric leakage point of underground power cable is very important to reduce cost and time of maintenance and prevent electric shock accident through expedite repair of electric leakage point. This paper proposes a electric leakage point detection system underground power cable using of half-period modulated transmission waveform and earth electric potential measurement. The developed system is composed of transmitter to generate the wanted pulse waveform, receiver to measure and display earth electric potential by the transmitted pulse in electric leakage point and PC Software program to display of GPS coordinate on detection cable line. The performance of the electric leakage point detection system was tested in the constructed underground cable leakage detection test bed. The test results on signal generation voltage precision of signal transmitter, mean detection earth voltage, mean detection leakage current and electric leakage point detection error showed the developed system can be used in electric leakage point detection underground power cable.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.1105-1108
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• 2004

This paper describes the structural analysis result and load test result of accident EMU(Electric Multiple Units). Structural analysis and load test of EMU were performed for the criteria of safety assessment. Structural analysis using commercial I-DEAS software provided important information on the stress distribution and load transfer mechanisms as well as the amount of damages during rolling stock crash. The purpose of the load test is to evaluate a safety which carbody structure shall be considered fully sufficient rigidity so as to satisfy proper system function under maximum load and operating condition. The results have been used to provide the critical information for the criteria of safety assessment.

• Journal of the Korean Society of Safety
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• v.19 no.2
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• pp.34-40
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• 2004

This paper presents an analysis of SAR(Specific Absorption Rate) distribution characteristics in a head model using FDTD(Finite Difference Time Domain). In this study human head was modelled in four elements-layered structure, consisting of skin, fat, skull and brain. To calculate the electromagnetic fields wihtin the head model, FDTD method was used. In the FDTD method, the electromagnetic wave is analyzed by solving a Maxwell's equations repeatedly. For the calculation, distance between power source and head model increased by 10[m]. Power density and incident electric field intensity were calculated. Based on the incident electric field, the program which calaculated internal electric fields intensity and SAR calculation of the head model were developed. The results of developed program using FDTD were compared with those of a commericial programs, which showed the availability and usefulness of the suggested scheme in this paper.