• International Journal of Safety
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• v.4 no.2
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• pp.18-23
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• 2005

There are many electrical connections in the electric apparatus and most fires due to a fault contact result from a failure or misuse of electric apparatus and installation. The fault contact happens between electrical connections by the loose and the mechanical vibration. In this paper, we have investigated thermal and electrical properties of screwed electric contacts due to the mechanical vibration. The exciter was connected to a signal generator and power amplifier that provided the vibration frequency and amplitude. The vibration, temperature and voltage data were sent to a data acquisition system (DAQ). In the case that fault contact took place, the arc happened between the screwed electric contact and electric wire, heat due to the arc was transmitted to the adjacent insulators, for which the oxide could be generated more. In addition, a spark was generated and the insulator began to melt. Thus, the possibility of electrical fire became the highest in this case. Finally, when the fault contact takes place due to vibration, the hazard of an electric accident is very high.

• Journal of Radiation Protection and Research
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• v.21 no.3
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• pp.201-215
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• 1996

Radiation and radioactive materials serve man in many beneficial ways. Diagnostic X-ray, radiation therapy, and other nuclear medicine uses of radioactivity save thousands of lives each year. Industrial application of radiation, such as radiography, make many manufactured products more reliable and less expensive. Nuclear power plants are producing more electrical power each year and reducing our dependence on imported oil. However, radiation can and dose produce harmful effects particularly as the reault of a radiation accident in which a victim receives as the result of a radiation accident in which a victim receives a large dose. Fortunately such accidents are very rare and recently we need more electric power produced by nuclear power plants. Considering increase of use of radiation or radioactive materials, we have to establish the radiological emergency response system prepared for radiation accidents.

• Proceedings of the KIEE Conference
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• 2003.10b
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• pp.289-291
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• 2003

Railway takes an important role of transporting massive passenger and freight. Accidents which occur related to trains have a risk of serious loss of lives, so those accidents need to be controlled urgently Therefore moving picture transmission system is required which transmits exact information of moving picture of accident status to CTC and also communication line is also required with it. By using WTB line as a wayside transmission line, railway telephones, fax and train service information are provided to local offices. As transmission line improving project, optical cabling work is being processed by phases. Therefore optical fiber line is more effective way for a communicating way between stations than coaxial transmission line. This Paper considers connecting method when optical fibers is used for moving picture data transmission of train accidents and its problems.

• Proceedings of the KIEE Conference
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• 2003.10b
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• pp.286-288
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• 2003

Accidents at level crossing where railways and roads cross cause many casualties because of collision of cars etc and it also has a risk of the 2nd accident of trains. it is the most vulnerable point in the railway safety. Fundamental solution for accidents at level crossing is making the crossings cubic. but it can't be easily progressed because of environmental and financial difficulties. every kind of anti-accident measures are being strived for. one of the strived results is level crossing obstacle detector which automatically detects obstacles like defected cars etc in the middle of level crossing and transmits the information of obstacles to the approaching train. However present level crossing obstacle auto detector needs high expenses to be installed and has difficulties that lenses of beam transmitter, beam receiver should be cleaned in snowing winter. this document reviews level crossing obstacle auto detector using ultrasonic sensor to measure these difficulties.

• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.653-654
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• 2006

This paper proposes a new linear magnetic damper for absorbing shock from a crash accident involving high speed vehicles. The magnetic damper is composed of a conductive plate, a yoke and permanent magnets which are constructed to a Halbach array to improve the damping force. In order to calculate the damping force, finite element analysis(FEA) using J-Mag, a commercial FEA tool, is performed and the results are validated by the experiment. Also, the design optimization of the plate generating the eddy current causing the damping force performed to obtain the most efficient damping force. Finally, the specifications and the performance of the proposed magnetic damper are represented.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1197_1198
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• 2009

The development of Technology study for preventing of accident and reducing the risk through the intelligence of level crossing is provide the detection of stopped car at railway crossing with the most advanced intelligence technology such as sensor, computer, communication and date processing and transmit to the operational staff on broad for reaction or make the train stopped automatically through the connection with train. Also this study include that showing the situation of crossing railway when the train is approached and prevent the accident and reduce the risk through the connection of road transit signal system. On this study is performed the test through the date from spot level crossing and the development of video detection algorism for stopped road transit vehicle at level crossing with intelligent system.

• Proceedings of the KIEE Conference
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• 1998.11c
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• pp.1054-1060
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• 1998

Previous counter-current flow limitation (CCFL) and critical heat flux (CHF) studies included investigations on the inlet entrance, inclined channel and gap effects for the most part. In this study, the local CHF correlation was presented to be used in the numerical analysis for the 3 dimensional hemispherical geometry. Also, first-principle analyses were performed to determine the maximum heat removal capability from the debris through the gap that may be formed during a core melt accident. The maximum heat removal capability by gap cooling can be applied in quantitatively assessing the severe accident management measures.

• Proceedings of the KIEE Conference
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• 2005.11b
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• pp.316-318
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• 2005

Increasing elevator system every year that is directly connected passenger's safety and connected peculiarity Reliability of each variety equipment that is composing elevator is linked with passenger's safely, and prevent accident is important. Malfunction by electric part of elevator system that is composing elevator is not easy to examine closely the cause. Estimation about malfunction of component by electric power quality must consist among them. In this paper, inspect elevator accident figure to examine effect that electric power quality gets on elevator that see and presented thing for research direction and necessity of electric safety consideration by such electric malfunction.

• Proceedings of the KIPE Conference
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• 2005.07a
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• pp.131-133
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• 2005

Recently the harmonic generation has declined electricity quality and has bad influence on the electrical installation including OA(Office Automation), FA(Factory Automation), IT(Information Telecommuni-cation) devices and so on. The study of harmonics be greatly interested in diagnosis accident with harmonics was not merely guesswork but clarify the cause by experimental data at these days. Therefore, it is necessary development of AC power source for correct experiment with reliable data. In this paper, we realized the AC power source that can produce and compose harmonics for analysis of accident with harmonics.

• Proceedings of the KIEE Conference
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• 2005.07e
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• pp.67-69
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• 2005

Due to the unusual change in the weather to be increased suddenly, the damage of the lightning accident is recently more increased than before. Many water treatment facilities are operated by automatic control or by remote control. Automatic control systems are adopted in water treatment facilities. So there are damaged by lightning inevitably. This study is intended to measure and analyze the lightning accident occurred by the lightning and to show the methods minimizing the lightning accidents.