• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.382-384
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• 2000

산업의 발달에 따라 배전계통의 자동화가 서서히 자리 매김하고 있다. 이에 따라 배전계통에서 발생하는 사고를 계통의 상태와 신뢰도를 동시에 만족시키고, 빠른 시간 내에 복구하는 문제는 매우 중요한 문제로 대두되고 있다. 배전계통 사고복구 문제는 많은 개폐기들의 조합에 의해 구성되어 있고, 계통의 구성상태 와 연계선로의 예비력 등 많은 제약조건들로 인하여 사고복구에 많은 시간이 걸린다. 본 논문에서는 유전 알고리즘과 Tabu Search (TS) 기법을 이용하여 계통의 사고 후 선로손실과 신뢰도손실을 최소로하는 배전계통 사고복구 알고리즘을 제안하고자 한다. 전역 최적해 탐색 및 여러 해의 동시 탐색이 가능한 유전알고리즘과 전역적 탐색은 약하지만 빠른 시간 내의 국부적 탐색(local search)이 우수한 TS를 서로 연계한 알고리즘의 우수성을 계통의 모의실험을 통하여 증명하였다.

• Journal of Power System Engineering
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• v.13 no.5
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• pp.82-88
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• 2009

The purpose of this paper is to provide technical background, techniques and actual diesel engine signature analysis evaluation result. Engine signature analysis(ESA) is a process for monitoring the material condition of diesel engine using external sensors, eliminating the need to periodically disassemble the engine. ESA is also used to balanced the engine. Engine balancing is the process of tuning the engine so that all cylinders carry equal load. ESA is a useful tool to non-intrusively determine the operability and performance and assessment of the material condition of internal component of a diesel engine.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.2202-2203
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• 2008

축전지는 비상용 전원으로 사회 많은 분야에서 다양하게 사용되며, 유사시 예비전원으로 그 중요성이 부각되고 있다. 이러한 경우에 사용가능한 축전지를 선별하고, 그 상태를 체크하는 것은 무엇보다도 중요하다. 본 논문에서는 축전지의 잔존수명을 보다 짧은 시간에 효과적으로 분석할 수 있는 순간방전시험을 이용하여 축전지의 잔존수명을 판단하고자 하였다. 실험결과 순간방전 시험을 통한 mode 2에서의 임피던스 값과 실부하 방전시험 결과가 서로 일치함을 알 수 있었으며, 이를 통해 축전지의 잔존수명을 파악할 수 있을 것으로 사료된다. 본 논문은 추후에 계속되는 축전지 잔존수명 분석을 위한 기초 자료로 활용될 수 있을 것이다.

• Annual Conference of KIPS
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• 2023.05a
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• pp.13-14
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• 2023

뇌의 전기적 신경활동을 측정하는 뇌전도(EEG)는 저렴하게 취득할 수 있고 높은 시간 해상도를 갖는 반면 공간적 정보를 제공하지는 않는다. 기능적 자기공명영상(fMRI)은 혈류변화를 감지하여 뇌활동을 측정하는 방식으로서 높은 공간 분해능을 갖지만 고가의 비용과 설비를 요구한다. 최근 저렴하게 취득할 수 있는 EEG 데이터로부터 딥러닝을 사용하여 fMRI 합성영상을 생성하는 기술이 제안되었지만, 저주파수 대역에서 EEG와 fMRI 간의 뇌과학적 상관관계를 반영하지는 않는다. 본 연구에서는 휴식상태에서 취득된 EEG 데이터를 스펙트로그램으로 변환한 후 저주파수 특성을 사용하여 fMRI 합성영상을 생성하는 U-net 기반의 크로스 모달리티 변환 모델의 실현가능성을 평가하였다.

• Journal of Korean Academy of Nursing
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• v.27 no.3
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• pp.648-659
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• 1997

The purpose of this study was to study what effect providing the patient with preparatory concrete information had on the state anxiety depending on coping styles of patients undergoing cardiac catheterization. State Anxiety scores for 32 patients who had cardiac catheterization were examined after information was provided about the test using an audio tape. The state anxiety of patients who had a high trait anxiety level was compared to that of those who had a low trait anxiety level. The state anxiety of those who had a monitor type were compared to those of patients who had blunter type. The Trait and State Anxiety Scale of Spielberger, Miller's Behavioral Style Scale, and Krantz's Health Opinion Survey and Visual Analog Scale (Ⅰ, Ⅱ) were used. Findings were as follows : 1. Among the demographic characteristics, gender difference of the patients was significantly different for the trait anxiety level. Female patients had higher trait anxiety level than male patients. 2. Analysis of state anxiety scores indicated that the mean score of the state anxiety prior to the test was higher than the mean score of the state anxiety examined after the test. The difference was statistically significant. 3. Among the patients, 14 patients (43. 7%) used monitor type, while 18 patients (56. 3%) used blunter type. The means of preference for information measured on the Krantz' subscale was 2. 45. 4. The study results indicate that the state anxiety level of those who had a low trait anxiety level was lower than that of those who had a high trait anxiety level. 5. State anxiety levels depending upon the kind of coping style which patients used during the test were not significantly different. This study did not identify the influence of preparatory concrete information on the state anxiety depending on coping styles, and there fore a quasi-experimental study using a large sample according to different types of information, and the amount of information, coping styles is recommended.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.2
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• pp.445-451
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• 2014

Dual LED lantern, which is composed of two light sources in one lantern, can be utilized as an auxiliary light source when the main light source is in trouble. Nevertheless, there are no way to obtain status information of the system and control the light source if the current domestic standard protocol is applied, since the standards for dual LED lantern are not defined yet. Regarding to this problem, we suggested expanded lantern protocol for management system of dual LED lantern based on current domestic standard. Also, we confirmed the normal operation of dual LED lantern after implementing suggested protocol on the developed management system. Control system suggested and implemented in this study is tested not only its function of controlling and acquiring the operating status of dual LED lantern, but also its capability to utilize as a control system of currently used LED lanterns.

• The Journal of the Korea Contents Association
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• v.15 no.9
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• pp.562-575
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• 2015

This study aims to draw a Housing development scheme of elderly housing, including the urban, suburban and resort type according to location type, which is based on a Demanding Characteristics of preliminary elderly for elderly housing. In addition, The comprehensive implication tells that the preliminary elderly who wants the urban elderly housing type have a more personal characteristics than other types. So it should be considered according to personal characteristics. Next, when we choose the suburban elderly housing type and predict the demand for housing development, it should not only considers factors such as the Unmarried children, Health status, Current housing size and Plans for economic activity in old age but also considers factors such as the Accessibility, Convenience, Investment and Environment characteristics of elderly housing preference. Next, when we choose the resort elderly housing type which based on the fact that a few detailed parameters of current housing characteristics exist, it should be based on the current housing characteristics of preliminary elderly. In addition, it should consider a pre-investigation for elderly housing preference in order to select the housing type. Because a comprehensive preference such as the comfort, convenience, safety, investment, environmental characteristics is considered as major determinants factors.

• Communications of Mathematical Education
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• v.36 no.2
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• pp.287-311
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• 2022

This study was related to the cases in which pre-service elementary teachers designed math lessons tailored to math underachievers with learning trajectories and universal design for learning. Learning trajectories can be a basis to identify students' current state of understanding and development, and make a lesson plan responsively tailored to underachievers' state. And universal design for learning is a framework that removes potential barriers that may exist in math lessons from the time the lessons are planned, and guides the rich learning environment accessible to all learners. In order to provide an experience of designing math lessons considering the characteristics of math underachievers, this study required pre-service elementary teachers to create learning trajectories and make lesson plans with the principles of universal design for learning. The characteristics of the learning trajectories shown in the lesson plans and the results of applying the principles of universal design for learning were analyzed. By discussing the results, implications were derived regarding the necessity of lesson planning for math underachievers and the development of lesson planning competency of pre-service elementary mathematics teachers in teacher education.

• The Journal of the Korea Contents Association
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• v.17 no.3
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• pp.305-318
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• 2017

The purpose of this study is improving the teachers' self-efficacy for pre-secondary music teachers. The research questions for this study were the improvement for teachers' self-efficacy for pre-secondary music teachers and the pre-secondary music teachers' perception about peer mentoring. In this study performed the interview and analyzed the in self-reflection journal in order to identify the improvement effect of teachers' self-efficacy and the participants' perception change in the peer mentoring. As the results from analyzing the change in participant's perception about peer mentoring the mentors had the opportunity to review previous learning contents and practice experiences while developing their team activity and for the mentees. Mentees said that they were given various help from the mentors' advices and their interactions and communication with mentors. From these results, it could identify that there was positive change in participant's perception about the peer mentoring. Based on these results, this study analyzed that it would need to require some chances for pre-secondary music teachers to be given some educational practice and field experience utilizing various teaching methods in order to improve their self-efficacy and the perception of peer mentoring.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.9
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• pp.26-31
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• 2003

Aging aircraft accumulates widespread fatigue damage commonly referred to as multiple site damage(MSO). For ductile material such as 2024-T3 aluminum, MSO may lower the service life below that which is predicted by conventional fracture mechanics. The present paper is concerned with the fatigue life extension by pre-indentation technique for thin 2024-T3 aluminum plate to decelerate the crack propagation rate in the panels with MSO. The panel with fastener holes can be simply modelled by Hole/Slot type Middle-Tension specimen. Results of fatigue testing show significantly improving failure cycles from 10 to 40 times. This retardation effect is decreased by increasing the loading level in the constant amplitude loading. In the sense of retardation mechanism, the crack propagation rate is gradually attenuated by entering the indentation mark and maintains at the lowest value for a long period after the edge of crack passes the center of indentation area.