• 대한안전경영과학회지
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• 제8권2호
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• pp.91-102
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• 2006

Korea Railroad Research Institute developed the driverless rubber-tired Korean-AGT system from 1999 to 2005 and has done its performance and reliability tests on the test line at Gyeongsan-city. We made the reliability management program to control required the RAMS(reliability, availability, maintainability & safety) of the K-AGT system. Therefore, we demonstrated the development and application of Reliability DB program. The main functions of K-AGT Reliability DB program manages failures and maintenance data systematically from the test line through test period and provides various analysis results based on the inputted data.

• Journal of Audiology & Otology
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• 제24권2호
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• pp.107-111
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• 2020

The present study aimed to determine the test-retest reliability of subjective visual horizontal (SVH) testing when tested with solid and dotted line images. In this repeated measures study, 36 healthy young Malaysian adults (mean age=23.3±2.3 years, 17 males and 19 females) were enrolled. All of them were healthy and had no hearing, vestibular, balance, or vision problems. The SVH angles were recorded from each participant in an upright body position using a computerized device. They were asked to report their horizontality perception for solid and dotted line images (in the presence of a static black background). After 1 week, the SVH procedure was repeated. The test-retest reliability of SVH was found to be good for both solid line [intraclass correlation (ICC)=0.80] and dotted line (ICC=0.78). As revealed by Bland-Altman plots, for each visual image, the agreements of SVH between the two sessions were within the clinically accepted criteria (±2°). The SVH testing was found to be temporally reliable, which can be clinically beneficial. Both solid and dotted lines in the SVH testing are reliable to be used among young adults.

• 대한청각학회지
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• 제24권2호
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• pp.107-111
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• 2020

The present study aimed to determine the test-retest reliability of subjective visual horizontal (SVH) testing when tested with solid and dotted line images. In this repeated measures study, 36 healthy young Malaysian adults (mean age=23.3±2.3 years, 17 males and 19 females) were enrolled. All of them were healthy and had no hearing, vestibular, balance, or vision problems. The SVH angles were recorded from each participant in an upright body position using a computerized device. They were asked to report their horizontality perception for solid and dotted line images (in the presence of a static black background). After 1 week, the SVH procedure was repeated. The test-retest reliability of SVH was found to be good for both solid line [intraclass correlation (ICC)=0.80] and dotted line (ICC=0.78). As revealed by Bland-Altman plots, for each visual image, the agreements of SVH between the two sessions were within the clinically accepted criteria (±2°). The SVH testing was found to be temporally reliable, which can be clinically beneficial. Both solid and dotted lines in the SVH testing are reliable to be used among young adults.

• KIEE International Transactions on Power Engineering
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• 제4A권2호
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• pp.91-99
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• 2004

This paper illustrates a tie line constrained equivalent assisting generator (TEA G) model considering forced outage rates of transmission systems for reliability evaluation of interconnected power systems. Interconnections between power systems can provide improved levels of reliability. It is expected that the TEAG model developed in this paper will prove useful in the solution to problems related to the effect of transmission system uncertainties in the reliability evaluation of interconnected power systems. The characteristics and concept of this TEAG considering transmission systems are described in detail by sample studies on a simple test system.

• 정보처리학회논문지B
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• 제17B권2호
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• pp.115-124
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• 2010

최근 스테레오 정합 기술은 정합하고자 하는 픽셀을 포함한 국부적인(local) 영상의 정합 비용과 시차의 변화 비용을 누적하는 전역적(global)인 방법을 많이 사용하고 있다. 특히 전역적 스테레오 정합에서도 비용누적 (cost accumulation)의 방향을 일반적인 수평방향이 아닌 다수의 방향을 사용하는 연구가 늘고 있다. 본 논문에서는 기존의 스테레오 정합 기술을 다중 방향성 정합 기술로 확장하는 방법을 제안한다. 픽셀의 국부적인 정합 비용은 단순한 NCC (Normalized Cross Correlation)를 사용하였고 전역적 정합 기술의 하나인 정합선 최적화(Scan-line Optimization) 방법을 다중 방향으로 확장하는 기술을 제안하였다. 우선 정합선 최적화를 다중 방향으로 실행한 후 이들 결과를 이용하여 신뢰도가 높은 시차영상 (disparity image)을 획득한다. 반복적인 다중 방향 정합선 최적화 시행 후, 시차영상에서 남은 공백은 홀 복원 방법으로 계산한다. 시차가 구해진 픽셀에 대해서는 신뢰도 점수를 매긴 다음 이 점수를 확산하여 신뢰도 점수 테이블에서 가장 높은 값을 가지는 시차값으로 홀을 복원하였다. 제안하는 기술을 미들버리(Middlebury)의 스테레오 영상을 사용하여 오차를 분석하였다. 기존의 전역적 방법과 제안 기술을 이용하여 시차영상을 계산하고 그 오차를 비교하였다.

• KIEE International Transactions on Power Engineering
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• 제4A권2호
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• pp.84-90
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• 2004

This paper presents a new method for choosing the best line for transmission system expansion planning considering the highest reliability level of the transmission system. Conventional methodologies for transmission system expansion planning have been mainly focused on economics, which is the minimization of construction costs. However, quantitative evaluation of transmission system reliability is important because successful operation and planning of an electric power system under the deregulated electricity market depends on transmission system reliability management. Therefore, it is expected that the development of methodology for choosing the best lines considering the highest transmission system reliability level while taking into account uncertainties of transmission system equipment is useful for the future. The characteristics and effectiveness of the proposed methodology are illustrated by the case study using a MRBTS.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.1014-1023
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• 2008

The K-AGT test line is managed similarly to revenue operation and operated automatically 120km per day, total 90,000km from August 2004 to December 2007. To enhance reliability of developed system, maintenance information system based on RCM is applied. The maintenance program applied in test line is based on RCM which prevent a fault before it happens and a fault made in test line is analysed by reliability growth test. Vehicle system, power supply system, signalling system, track and infrastructure are built in test line and it is reviewed enhancing system performance and changing designs to commercialize through reliability growth analysis method.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 C
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• pp.1256-1258
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• 1999

Electric industry has been the object of major reforms in many countries. These reforms are aimed at attaining efficiency through competition. Thus network companies do not charge transmission cost for line user the same as method at past. This paper presents a transmission cost allocation through reliability differentiated transmission pricing in competitive electric industry. The proposed method considers only the line capacity affecting the reliability of transmission pricing under normal state and contingency state.

• 전기학회논문지
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• 제57권7호
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• pp.1129-1134
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• 2008

This paper proposes a reliability evaluation for interconnection planning using a tie line equivalent assisting generator model (TEAG) that considers the uncertainties of the interconnected transmission systems and the tie lines. Development of this model was triggered by the need to perform probabilistic reliability evaluations on the NEAREST (North East Asia Region Electric Systems Tied) interconnection. The TEAG is the basis for the newly developed interconnection systems reliability evaluation computer program, NEAREL. The model is capable of considering uncertainties associated with generators, tie lines, and the tied grids. Reliability evaluations for six interconnection scenarios involving the power systems of six countries in the Asian north eastern region were performed using NEAREL. Sensitivity analysis was used to determine reasonable tie line capacities for three interconnected country scenarios of the six countries. Test results and summarized comments of the scenarios are included in the paper.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 A
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• pp.79-82
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• 2002

The addition of switches to a distribution feeder does, in general, increase reliability by decreasing the duration of the outage of many to the customers on the feeder. To cover its service area so that feeder-level delivery reaches sufficiently close to all customers, feeders typically split their routes many times, in what is often called a lateral feeder. It is interesting to note, however, that the effectiveness of a switch is very much dependent on the types of lateral feeder. The types of lateral are classified into two types. The first is loop lateral feeder that can connect its load to an adjacent feeder through a tie line in case that a fault occurs in its feeder and it is laid out so that every feeder has complete fault backup through re-switching of its loads to other sources like a main feeder. The second is the radial lateral feeder cannot connect its load to an adjacent line, no provision is made for contingency backup of feeders. There are no other circuits in the radial lateral feeder form which to restore power. In this study, we evaluate the effectiveness of a switch installation between on the radial and loop lateral feeders to increase reliability by decreasing the duration of the outage. These results can help power utility to design the switch layouts on the radial and loop lateral feeder system.