• The Journal of Korean Institute of Communications and Information Sciences
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• v.12 no.4
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• pp.399-404
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• 1987

By using the principles of the three line coupled, the equivalent admittance parameters of the band-stop filter of the three line two port spurline for MIC are derived. The frequency and in/output impedance characteristics of the filter were studied. One-section spurline bandstop filter with their stopband cented near 4GHz have been fabricated and tested. The results show good agreement between the theoretical centre frequency and the experimental results.

• Proceedings of the KOSOMBE Conference
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• v.1996 no.11
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• pp.353-356
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• 1996

Early this year the construction of new high voltage power lines have been forced to stop due to the demonstration of residents in Kwa-chun. According to mutual agreement between the residents and Korea Electric Power Corporation, electromagnetic field(EMF) from present power lines was measured and EMF after completion of new power lines was estimated. The results show that EMF near power lines Is relatively low, and EMFnear electric substation is quite high due to the short distance between the power lines and ground. For 4 conduction 345kV line, magnetic field decreases to 3mG at the distance of 50m from the power line.

• Proceedings of the KIEE Conference
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• 2005.07b
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• pp.1047-1049
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• 2005

Hydraulic power plant is operated for peak load and frequently start-stop because of no continuous operation. So the fault can happen due to field voltage swing in the middle of starting or reactive power swing on the line. On this research, we want to analyze that this status influence on line and generator. we hope this research can contribute to the power quality improvement.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.1807-1820
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• 2008

The station area development planed to improve the old and narrowed station and to enhance the train passenger's convenience through private capital attraction in the past. But it has been faced with difficulty for the creative of transfer demand. Because of lean upon building facilities were caused by shortage of business profitability as to development of the upside a railway line, and lack of public utilities. The station area development requires that it's trend to large scale development of station areas, korail's direct development, deputation of specialty company to development, collaboration between local government and korail in development, diversification of process & installed facility, building multi-transfer center and one-stop transfer system. This trend caused by low profitability in development of the upside a railway line. The purposes of study are to make the system and law reflected to the property of station area development, investment in kind of needed land, and change railroad areas to high-rise and complex development, and make a forum between government and korail, etc.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.3 no.2 s.5
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• pp.75-83
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• 2004

July 1, 2004 Seoul Metropolitan city is operating the Median Bus Lane System on Gangnam Main Street, Seongsan-Susaek-ro (Road) and Dobong- Mia-ro (Road) as one of the systematic reorganizations in public transportation. It has been assumed that there was an improvement in the speed of bus considering that the Median Bus Lane System practiced on Cheonho-daero (Main Street) since 1996 have had 35km/h on the average. If the Median Bus Lane goes into effect, there is a problem with the left turn on the crossroad. The buses go on the existing first lane so that the left fuming cars cannot help but turn left on the second lane. In case that the Median Bus Lane is put into practice, the left turn on the crossroad should not be allowed. However, if the left turn is not permitted on the crossroads in the aforementioned main streets, neighboring residents will complain about it and there will be some difficulties in finding other detour. On the premise that the prevalent left turn on the crossroads is allowed while the Median Bus Lane is being put into practice, this study suggests the separation of a stop line between buses and other vehicles as a way of fuming left in a safe manner and a way to calculate the appropriate distance.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.15 no.3
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• pp.52-59
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• 2016

COSMOS system which was developed in Seoul for real-time signal control was designed to judge traffic condition for practicing signal operation. However, it occurs efficiency problem that stop line detection and queue length detection could not judge overflow saturation of street. For that reason, following research process GPS data of Seoul city's corporationowned taxi to calculate travel speed that excluded existing system of stop line detection and queue length detection. Also, "Research of calculating queue length by GPS data" which was progressed with following research expressed queue length. It is based on establishing algorithm of judging congestion situation. The algorithm was applied to a few areas where appeared congestion situation consistently to confirm real time traffic condition with established network. [Entrance of the National Sport Institute ${\rightarrow}$ Gangnam station Intersection, Yuksam station intersection ${\rightarrow}$ National Sport Institute.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.1
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• pp.156-161
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• 1992

In this research a monitoring system for turning using NC information and the current of feed motor as a monitoring signal was developed. The overall system consists of modules such as learning process, NC data transmission, generation of forecast information, signal acquisition, monitoring and post process. In the learning process, the reference data and the cutting force equation necessary for monitoring are obtained from the accumulated monitoring results. In the generation of forecast information, the information of forecasted cutting forces is acquired from the cutting force equation and NC program and appended to each NC block as a monitor code. Reliability of monitoring is improved by using the monitor code in the real-time monitoring. Monitoring module is divided into two parts : the off-line monitoring where errors of NC program are checked and the on-line monitoring where the level of motor current is monitored during cutting operations. If the actual current level exceeds the limit value provided by the monitor code in the level monitoring, it is recognized as abnormal. In the event of abnormal status, the post processor sends the emergency stop signal to NC controller to stop the operation. Actual experiments have shown that the developed monitoring system works well.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.3
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• pp.1734-1739
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• 2014

In this paper, microstrip low pass filter using transmission line with the modified DCRLH structure is designed and fabricated to be removed a spurious resonant mode, and a deep attenuation in stop band. The low pass filter is composed of shunt open-stub to get a deep attenuation and series short-stub to eliminate the spurious harmonics in stop band. In this way, the spurious harmonics occurring on the higher order frequency are suppressed and the filter performance is improved. Insertion loss and VSWR of the fabricated microstrip low pass filter in the passband from DC to 1.5 GHz is 1.26 dB and 1.65, and attenuation on the stopband from 1.84 GHz to 2.18 GHz is less than -100 dB. And also this filter has a good performance for 20 watt power test.

• Carbon letters
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• v.2 no.2
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• pp.113-119
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• 2001

The advanced method for $CO_2$capture is currently one of the most important environmental issues in worldwide and it is therefore necessary to have available technologies, which minimize the discharge of $CO_2$ including Carbon-14 from nuclear facilities into the atmosphere. A key aspect of this work is to provide the technically principal data required to improve a $CO_2$ removal system for the utilization of regenerative sorbent use, specifically include suggestions regarding its modified column design (parallel dual-bed assembly), stop-restart operation and the economic feasibility of sorbent use. The removal performance of soda lime and the effects of relative humidity (RH) and packing bed-depth (BD) on $CO_2$ removal were investigated. In a single-bed, it revealed that the utilization of soda lime for $CO_2$ removal at line velocity of 13 cm/sec and bed depth of 12 cm increased with the increased relative humidity up to 85%. However, in the parallel dual-bed assembly applied with the stop-restart operation, a maximum utilization rate of soda lime for $CO_2$ removal was obtained even at 55% of RH and 8 cm of BD, specifically the utilization rate of soda lime by using this $CO_2$ removal assembly was about two-fold superior to that in a single-bed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.5D
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• pp.723-730
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• 2006

Recently, The flexible moving block system in train operation has been introduced to the worldwide rail transportation markets. This paper is a comparative study of the conventional fixed block systems effects and the flexible moving block system on train operating time saving. Based on the literature review, the new algorithm is developed. It is to calculate the optimum headway time of the train. The proposed algorithm can overcome some of the existing algorithm problems, such as the limits of the data and unaware of the rail characteristic. The total travel time saving effect has been analyzed by applying the skip stop scheduling system to the each block system. The results of this study indicated that the total travel time is approximately 40% decreased and the schedule velocity is approximately 24% improved when the moving block system is applied. The results of this study could be used as a theoretical basis for the selection of rail signal system in Seoul's subway number 2 line.