• Journal of the Korea Computer Industry Society
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• v.4 no.12
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• pp.1013-1020
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• 2003

In this paper, the discharge properties due to time variation were investigated in order to estimate a electrical performance of the insulator for small transformer. AC 10[kVl applied to specimen was converted to $\pm$5[V] and stored to personal computer through A/D converter. A period of applied wave form and discharge values were divided into 64 parts and discharge values generated during 10 seconds were accumulated by phases. As a result, it was confirmed that count of discharge, total discharge and the variation degree of average discharge were decreased as time elapsed.

• Korean Journal of Computational Design and Engineering
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• v.4 no.4
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• pp.355-359
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• 1999

This paper presents a method for determining machining parameters in electrical discharge machining process (EDM) based on discharge area. The parameters are the peak value of currents, the pulse-on time, and the pulse-off time, on which the EDM performance depends chiefly. The optimal machining parameters are closely related on discharge area, which can be calculated from a tool electrode and a discharge height. In the paper the discharge area is obtained from NC code for machining the tool electrode instead of its geometric model. The method consists of following three steps. First a Z-Map model is constructed from the NC code. Secondly, the discharge area is obtained from the Z-Map model and a Z-height. Finally, the machining parameters are calculated from the discharge area. An introduced example shows that the machining parameters are calculated by the using a Z-map model obtained from the machining data for a tool electrode.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.9
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• pp.1297-1301
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• 2013

This paper analyzes of PD occurrence position through an analysis of the arrival time difference between the GIS partial discharge signal. Because of GIS (Gas Insulated Switchgear) is a facility very important power equipment and as part of the equipment that make up the power system, the stabilization of the power industry, which accounted for 88.5% share of GIS substation in the form of a substation is an important equipment for power supply. In the situation where we are gradually expanding the need for preventive diagnosis in order to improve the efficiency of equipment management and failure prevention for Preventive diagnosis. In this paper as a method for extracting pre-defect of failure of GIS Apply the average value method of calculating the 5 times each using a pulse of the first time of the second pulse (${\Delta}t$) with an oscilloscope generation position PD(Partial Discharge). the results of GIS internal inspection, the partial discharge of the actual the position of the partial discharge was confirmed with an accuracy of about 82% of positions. Arrival time difference in the most effective manner if the partial discharge of GIS internal occurs by applying the averaging method and TOA(Time of arrival) method, the partial discharge occurs you through the measurement and analysis of PD signal occurs was confirmed in the experiment are presented and diagnostic methods location tracking.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.1
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• pp.27-33
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• 2000

This paper presents a method for determining machining parameters in 3-dimentional electrical discharge machining(EDM). The parameters are the peak value of currents, the pulse-on time, and the pulse-off time. It is known that they influence the performance of EDM more than the other else. The parameters are determined from the discharge area between a tool electrode and a work piece. The discharge area is directly influenced by the geometry of a tool surface and the tool discharge position. The discharge area on a tool discharge position is calculated from intersection curves between the tool surface and a horizontal plane. The grid search method is applied to determine the intersection curves. An example is introduced to show that the machining parameters are obtained from the surface geometry of a tool electrode.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.08a
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• pp.67-71
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• 2003

One of the most important problems in ADS method is that the method has too long addressing period, The addressing time can be defined as the sum of the discharge time lag and the duration of discharge current. If the addressing time increases, the sustaining period for display image should be decreased. As a result, the luminance of the PDP decreases. Therefore, the discharge time lag and duration of discharge current should be decreased in order to reduce the addressing time. In this paper, in order to improve addressing time, relationships between addressing time and cell structure in AC PDP was studied

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.488-493
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• 2006

Accurate river discharge is the most important factor in managing river basins and for successfully maintaining total maximum daily loads in Korea. It is not easy to measure the discharge directly in large rivers owing to physical and environmental constraints, even after investing much time and money. Recently, to overcome these historical drawbacks in river discharge measurement, we have developed the Automatic Discharge Acquisition & Management System (ADAMS) that scans the river cross-section and measures each cell $(1m{\times}1m)$ velocity using HADCP. The hardware system is composed of an HADCP sensor and winch, as well as a PC and software system for the discharge calculation module and hardware control module. It is controlled remotely via the internet and uses the velocity-depth integration method and the velocity-contour method for calculating river discharges. The characteristics of ADAMS are a ubiquitously accessible system, featuring real time automatic discharge measurement, remote control via the internet. The results using ADAMS at the Jindong stage site show less than 5% uncertainty and are 4 times more efficient than the ADCP & Q-boat system. This system can be used to measure any large river, river mouth or tributary river affected by backwater, all of which have a very difficult measuring real time discharge. The next generation of ADAMS will feature an upgrade to increase portability and GPS integration.

• Journal of IKEEE
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• v.19 no.3
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• pp.366-370
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• 2015

This paper proposes an alternating battery discharge method by balancing discharge time of battery cells, which significantly increases battery lifetime. In the conventional method, several battery cells are alternately discharged to make battery recovery effect, and this increases battery lifetime. In this case, there are some overlap intervals where several battery cells are ON to avoid system power cut-off, but this makes several problems due to the voltage differences of battery cells. To mitigate these problems, discharge time of battery cells are controlled to make battery cell voltages as equal as possible. Measurements show that the battery lifetime is exxtended by 19.2% in the proposed method.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.296-299
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• 2005

Time series of spring discharge data in Jeju island can provide abundant information on the spatial groundwater system. In this study, the classification based on time series of spring discharge was performed with clustering analysis: discharge rate and EC. Peak discharges are mainly observed in august or september. However, double peaks and late peaks of discharge are also observed at a plenty of springs. Based on results of clustering analysis, it can be deduced that GH model is not appropriate for the conceptual model of Groundwater system in Jeju island. EC distributions in dry season are also support the conclusion.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.08a
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• pp.72-75
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• 2003

Effects of delay and panel temperature on the discharge time lag and the controllability of weak discharge mode were studied under single cell driving circumstances of ac PDP. It was found that sufficient number of priming particle is necessary for inducing weak discharge in ramp voltage driving. Discharge time lag was reduced dramatically under elevated panel temperature condition It is speculated that decrement of discharge time lag at the high temperature is related to the reduction of diffusion loss of charged particles during the after glow.

• Proceedings of the KIEE Conference
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• 2003.07c
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• pp.1686-1688
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• 2003

Effects of delay and panel temperature on the discharge time lag and the controllability of weak discharge mode were studied under single cell driving circumstances of at PDP. It was found that sufficient number of priming particle is necessary for inducing weak discharge in ramp voltage driving. Discharge time lag was reduced dramatically under elevated panel temperature condition. It is speculated that decrement of discharge time lag at the high temperature is related to the reduction of diffusion loss of charged particles during the after glow.