• Proceedings of the KIEE Conference
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• 1995.07b
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• pp.616-619
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• 1995

This paper describes developement of on-line system for vibration signal analysis. In the power system, the main reason of transformer fault is due to a large amount of current by a short-circuit and a ground-fault. The electromagnetic force caused by fault-current deforms transformer windings and results in vibration pattern change. Therefore if the continuous on-line vibration monitoring on transformer is performed, an incipient failure can be detected. The developed system is composed of data acquisition devices, user interface program, signal processing program, diagnosis and trend analysis program, self diagnosis program and communication program.

• Proceedings of the KIEE Conference
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• 2006.10c
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• pp.491-493
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• 2006

We introduce Location PDA Program which is a mobile system to display current location on PDA. The current location is calculated based on collecting location through each fixed node. Each fixed node sends location information of mobile node to Cell Manager system. And then, Cell Manager calculates final location based on related information and sends it to every mobile system which is connected to server and displays current location.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2004.11a
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• pp.143-148
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• 2004

In order to see physical characteristics of water masses and tidal currents in Gamak Bay, some field surveys have been conducted using ADCP, Aanderaa current meter and CTD from May 17 to June 3, 2004. The northwest of the bay appeared to have a high temperature and a high salinity so that it coincided with the previous results. The distribution of temperature and salinity seemed to reflect the characteristics of water masses. At the south mouth of the bay, a northwestward-southeastward flow was dominant at the surface layer while a northeastward-southwestward flow was dominant at the bottom layer.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.329-331
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• 2003

PROSET2000 that is integrated protective management system had developed and used in order to automate the setting process of protective relays in transmission system protection. PROSET2000 have database for relay setting and automated for relay setting program within. This paper proposed PCM current differential relay setting program point of Object Oriented Programming paradigm using Unified Modeling Language about additional relay in PROSET2000. Nevertheless each relay uses same current differential but setting method is different. This paper discribed different thing about setting method of each relay and evaluated more effective and corrective relay setting program using UML.

• Proceedings of the KSR Conference
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• 1999.11a
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• pp.209-217
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• 1999

A catenary system should be designed to be an uniform elasticity over a span in order to maintain the lowest possible loss of contact between a pantograph and a contact wire. A elasticity disuniformity of a catenary can be regarded as a important design factor used for predicting the current collection performance for a catenary. There are a couple of formulas to calculate elasticity disuniformity of a catenary according to the literature survey, The effectiveness of these formulas is reviewed by performing catenary elasticity and loss of contact analysis for 5 different configurations of catenary systems using a beam element based FEM program, KRRI developed program, and the loss of contact by GASENDO, RTRI developed program, respective]y. The results reveals that these formulas are not suitable to predict the current collection performance for a catenary. Therefore, a new formula based on the standard deviation of the elasticity over a span is proposed in this study. The analysis results show that the new formula for an elasticity disuniformity of a catenary is very effective in predicting the current collection performance for a catenary.

• Journal of Food Hygiene and Safety
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• v.14 no.1
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• pp.104-114
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• 1999

This study was conducted to find out the proper ways of implementation of Hazard Analysis Critical Control Point (HACCP) concepts applicable to the current Korean food inspection system. The following recommendations are based on an in-depth review of the Canadian Food Safety Enhancement Program (FSEP), which is one of the leading HACCP programs adapted to the food industry. Since 1997, the HACCP system has been voluntarily applied to meat processing plants in Korea in accordance with the Food Protection Law. But the guidelines are obscure and inadequate to expand to the diversity of food plants, and are therefore only applied to a limited number of plants of small scale enterprise. For these reasons, it is necessary to prepare an enhanced food safety control program focused not only on the HACCP plants but also on the non-HACCP plants. The national program should be the fundamental framework of a food safety control policy enforced by all the relevant authorities. The Prerequiste Program of Canadian Food Inspection Agency and Sanitation Standard Operating Procedures (SSOP) of FSIS are good example programs for the non-HACCP plants. These programs, which are a major part of the HACCP system, could easily be adapted to the Korean food industry. To improve the current HACCP implementation guideline, it is necessary to develop a detailed implementation manual, generic HACCP model, training program, and an audit program.

• Journal of the Korean Society for Nondestructive Testing
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• v.35 no.4
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• pp.258-267
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• 2015

Eddy current testing is widely used for inspecting steam generator tubing in nuclear power plants (NPPs). The inspection technique for steam generator tubing in NPPs should be qualified in accordance with examination guidelines. When the components of a qualified system such as eddy current tester, probe, and data analysis program, are changed, the equivalency of the modified system to the originally qualified system must be verified. The eddy current tester is the most important part of an eddy current testing system because it excites and transmits alternating currents to the probe, receives coil impedance of the probe and generates signals for anomalies. The Korea Hydro & Nuclear Power Co., Ltd. (KHNP) developed an eddy current testing system with an eddy current tester and data acquisition-analysis program for inspecting the steam generator tubing in NPPs; this system can be used for an array probe and as a bobbin and rotating probes. The equivalency assessment for the currently developed system was carried out, and we describe the results in this paper.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.05b
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• pp.73-75
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• 2004

Resistive leakage current following arresters is an important indicator of ageing, but total leakage current and its harmonic analysis are widely used in diagnosing arrester soundness because of difficulties in measuring resistive leakage current. In this paper, we proposed a new method for measuring resistive leakage current, which is quite different from the conventional methods such as a self-cancel method and a synchronous rectification method. The proposed method is based on that the magnitudes of resistive leakage currents are equal at the same voltage level. To confirm the possibility of the proposed method. we fabricated a leakage current measurement device and designed an analysis program that can analyze resistive leakage current. Comparing with other methods. this technique does not need a complex circuitry and is very simple to complete.

• Journal of IKEEE
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• v.24 no.1
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• pp.161-169
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• 2020

In order to reduce the manufacturing cost of MCU chips used in applications such as wireless chargers and USB-C, compared to DP-EEPROM (Double Poly EEPROM), which requires 3 to 5 additional process masks, it is even more necessary MTP(Multi-Time Programmable), which is less than one additional mask and have smaller unit cell size. In addition, in order to improve endurance characteristics and data retention characteristics of the MTP memory cell due to E/P(Erase / Program) cycling, the distribution of the V_TP(Program Threshold Voltage) and the V_TE(Erase Threshold Voltage) needs to be narrow. In this paper, we proposed a current-type BL S/A(Bit-Line Sense Amplifier) circuit, WM(Write Mask) circuit, BLD(BL Driver) circuit and a algorithm, which can reduce the distribution of program and V_T and erase V_T, through compare the target current by performing the erase and program pulse of the short pulse several times, and if the current specification is satisfied, the program or erase operation is no longer performed. It was confirmed that the 256Kb MTP memory fabricated in the Magnachip semiconductor 0.13㎛ process operates well on the wafer in accordance with the operation mode.

• The Journal of Fisheries Business Administration
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• v.41 no.1
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• pp.1-24
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• 2010

The main goal of the study is to propose an objective and standardized evaluation system of stock enhancement programs. In order to achieve this goal, the study first suggested the need for stock enhancement program evaluation system through the review of current status and problems. Second, the study identified possible problems of the existing stock enhancement program evaluation by reviewing domestic and foreign evaluation systems. Finally the study proposed a new evaluation system and implementation plan of it. This study also classified the program evaluation criteria into ex-ante evaluation and ex-post evaluation according to the evaluation point in time, and applied the economic, political and technical feasibility tests into the evaluation of the stock enhancement program in order to solve the current problems of the evaluation. The evaluation process of the stock enhancement program is composed of an evaluation system design, estimation of weights using the analytical hierarchy process, design of estimation standard, conversion of scores and final summary of the evaluation. The central government takes the lead in the evaluation of the regional (metropolitan city or province) projects and the regional government is in charge of the evaluation of the local (city or county) projects. For the implementation of the ex-ante evaluation, either the regional or local governments ask for the evaluation and then submit an evaluation plan and other necessary documents to the upper level governments. The ex-post evaluation is then carried out by the upper level governments.