• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.63 no.11
• /
• pp.1582-1587
• /
• 2014

In this paper, we perform a modeling for the AT Feeder system in AC electric railway and we utilize the power EMTDC program to implement about AT feeder system modeling. In addition, we study the impedance characteristics of the AT feeder system and calculated fault current and impedance according to the distance due to fault accident. Based on it's result, fault current are compared between calculating the value and simulation value in EMTDC modeling. Impedance of power system is Largest at the middle point of the system and is smallest near autotransformer, and then showed that the fault current is inversely proportional to impedance characteristics.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.19 no.3
• /
• pp.240-245
• /
• 2006

Recently, as the road capacity reaches the limit and environmental problems becomes serious, there is gradually increased a need for railroad vehicles that are environment-friendly and have time regularity, reliability, and safety. Accordingly, in addition to conventional railroad vehicles, lots of vehicles are being newly developed. In this study, temperature sensors were adhered to transformer that is used in KHST(Korean High-Speed Train) to verify variation of temperature characteristics about transformer synthetically and efficiently. In the case that temperature of transformer exceeds reference temperature for running of KHST, overheating of transformer may cause a fatal accident of vehicle. Therefore, after on-line measuring system was constructed in vehicle, oil temperature and tank temperature were measured on real-time. Characteristics and main specifications of transformer in KHST were described in this paper. Also, measuring system for temperature measurement of transformer was explained in brief. Temperature data of transformer was acquired using measuring system, KRRI(Korea Railroad Research Institute) analyzed characteristic in contrast with comparing with temperature of transformer about month, running speed and running time.

• Journal of Korean Physical Therapy Science
• /
• v.4 no.4
• /
• pp.539-548
• /
• 1997

The purpose of this study was to determine the effects of FES on the clinical test patients who had disturbance gait due to cereberal vascular accident. The subjects for study were 16 hemiplegic patients (9 Male and 7 Female) who can gait with or without device. Their average age was 55 and they received average of 20.19 month of treatment collected data analysis was completed by using one-way analysis variable(ANOVA), Pearson ($-1{\leq}r{\geq}1$). The results were as follows : 1) There was difference in four variable (stride length,gait speed,gait cadence) between at the biginning and at the end of the treatment of FES (p<0.01). 2) There was relationship in capacity of activity between MAS and stride length (r = 0.751), gait speed (r = 0.689) but no relationship gait cadence (r = 0.236). 3) Age revealed relationship of stride length (r = -0.727), gait speed (r = -0.725), gait cadenc (r = -0.362). 4) There was no relationship in months post-CVA with MAS (r = 0.171), stride length (r = -0.110), gait speed (r = -0.096), gait cacedce (r = -0.154).

• Journal of Hydrogen and New Energy
• /
• v.23 no.4
• /
• pp.330-336
• /
• 2012

FCEV uses 250 ~ 450 V instead of using 12 V battery. High voltage vehicle can cause electric shock, fire and explosion accident. Therefore, it has potential factors that can cause hazard of safety for users. United states of America and Europe legislate regulations such as ECE R100, FMVSS 305 for regulating electrical safety during driving or after collision. The company manufacturing high voltage components must do advanced R&D about Method for improving and confirming the safety of high voltage. We develop the specific hardware components of high voltage wiring system for the power train system and power supply system of Hyundai Motors FCEV. This paper shows test method of insulative performance for securing the electrical safety of high voltage components such as power cable, connectors and buss-bar, and proposals the guide line value for human safety of FCEV according to the test result of our development components.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.18 no.7
• /
• pp.1695-1703
• /
• 2014

Manipulating a car navigation system while driving can lead to car accident due to loss of concentration. This will be more serious for elders or beginner drivers. Recently, a new Road Traffic Law in Korea prohibits drivers from watching or operating any video displaying devices. So the car navigation system came hard to use. In order to solve the issue we design and implement a novel system where a remote person can control the car navigation system on behalf of the driver. In the proposed system, we suggest to utilize the driver's smartphone for allowing sharing the Internet connection of the phone with the navigation system. The required smartphone application and the server will also be designed and implemented.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2008.06a
• /
• pp.377-378
• /
• 2008

Space charge formation in various glass materials under electron beam irradiation was investigated. Charging of spacecraft occurs in plasma and radiation environment. Especially, we focused on an accident caused by internal charging in a glass material that was used as the cover plate of solar panel array, and tried to measure the charge distribution in glass materials under electron beam irradiation by using a PEA (Pulsed Electro-Acoustic method) system. In the case of a quartz glass (pure $SiO_2$), no charge accumulation was observed either during or after the electron beam irradiation. On the contrary, positive charge accumulation was observed in glass samples containing metal-oxide components. It is found that the polarity of the observed charges depends on the contents of the impurities. To identify which impurity dominates the polarity of the accumulated charge, we measured charge distributions in several glass materials containing various metal-oxide components and calculated the trap energy depths from the charge decay characteristics of all glass samples. Furthermore, the dependence of the polarity of accumulated charges on the component of glass materials is discussed by using the models of energy bands.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.57 no.12
• /
• pp.2220-2227
• /
• 2008

The safety equipments of railway level crossing which are installed at intersections between roads and railway lines prevent level crossing accidents by informing all of the vehicles and pedestrians of approaching trains. The intelligent safety system for level crossing which employs information and communication technology has been developed in USA and Japan, etc. But, in Korea, the relevant research has not been performed. In this paper, we analyze the cause of railway level crossing accidents and the inherent problem of the existing safety equipments. Based on analyzed results, we design the intelligent safety system which prevent collision between a train and a vehicle. This system displays train approaching information in real-time at roadside warning devices, informs approaching train of the detected obstacle in crossing areas, and is interconnected with traffic signal to empty the crossing area before train comes. Especially, we present the video based obstacle detection algorithm and verify its performance with prototype H/W since the abrupt obstacles in crossing areas are the main cause of level crossing accidents. We identify that the presented scheme detects both pedestrian and vehicle with good performance.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.13 no.1
• /
• pp.21-30
• /
• 1999

The research for retecting of insulating deterioration in transforrrer has been studied from long ago and the analysis rrethod of combustible gas which is included in insulating oil has been used Recently the spreading effect of the accident is larger than before because of high voltage and large capacity, so on-line detecting system is needed and the study for the estimation of partial discharge signals location has begun. This thesis is the study for the sermating noise signal that is the greatest problem in ultrasonic signal measurement which is one of the method of estimation of partial discharge signals location. Because we can measure the number and location of signal, it is rossible to distinguish between the signal of partial discharge and the external noise. Therefore, we can devolop the credibility of detecting of insulating deterioration in transformer.former.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.17 no.3
• /
• pp.95-102
• /
• 2003

To Prevent the damage of power system facilities by snow accretion on transmission lines, a prototype expert system has been developed. The system has the basic functions of forecasting snow accretion on transmission lines and making a list of all feasible and effective deicing countermeasures to assist power system operators. As estimating of snow accretion on power lines and making countermeasure plans are very difficult to solve analytically, knowledge engineering can be an effective method for this problem. The heuristics about the effect of weather conditions on the snow accretion process on power lines and power system operation for the deicing constitutes main nile base. Simulation results based on past snow accretion accident data show that the proposed system is very premising.

• Journal of Power Electronics
• /
• v.16 no.1
• /
• pp.205-216
• /
• 2016

The manufacturing sector resorts to automation to increase production and homogeneity of products during mass production, without increasing scarce, expensive, and unreliable manpower. Automation in the form of multiple robotic arms that handle materials in all directions in different stages of the process is proven to be the best way to increase production. This paper thoroughly investigates robotic single-arm movements, that is, 360° vertical rotation, with the help of a brushless DC motor, controlled by a fuzzy proportional-integral-derivative (PID) controller. This paper also deals with the design and performance of the fuzzy-based PID controller used to control vertical movement against the limited scope of conventional PID feedback controller and how the torque of the arm is affected by the fuzzy PID controller in the four quadrants to ensure constant speed and accident-free operation despite the influence of gravitational force. The design was simulated through MATLAB/SIMULINK and integrated with dSPACE DS1104-based hardware to verify the dynamic behaviors of the arm.