• Journal of Electrical Engineering and Technology
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• 제12권3호
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• pp.996-1006
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• 2017

Phasor Measurement Unit (PMU) placement is a crucial problem for State Estimation (SE) of the power system, which can ensure that the power network is fully observed. Further, the observation reliability problem of the system has been concerned in the operation conditions. In this paper, based on modified weighted adjacent matrix ($A_w$), an optimal placement method is proposed to solve simultaneously two problems involving the optimal PMU placement problem and the observation reliability enhancement problem of the system. The purpose of the proposed method is to achieve both the minimum total cost and the maximum observation reliability, with a focus on increasing the security of observability, strengthening the observation reliability of buses as well as enhancing the effectiveness of redundancy. Simulations on IEEE 14, 24, 30 and 57 bus test systems are presented to justify the methodology. The results of this study show that the proposed method is not only ensuring the power network having the observability effectively but also enhancing significantly the observation reliability. Therefore, it can be a useful tool for SE of the power system.

• The Journal of Korean Physical Therapy
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• 제32권6호
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• pp.365-371
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• 2020

Objective: To investigate the action observation effects of functional electrical stimulation (FES) on the communication between motor cortex and muscle through corticomuscular coherence (CMC) analysis. Methods: Electroencephalogram (EEG) and electromyogram (EMG) of 27 healthy, nonathlete subjects were measured during action observation, FES, and action observation with FES, which lasted for 7sper session for 10 times. All trials were repeated for 30 times. Simultaneously measured EEG raw data and rectified EMG signals were used to calculate CMC. Only confidence limit values above 0.0306 were used for analysis. CMC was divided into three frequency domains, andthe grand average coherence and peak coherence were computed. Repeated ANOVA was performed to analyze the coherence value difference for each condition's frequency band. Results: CMC showed significant differences in peak coherence and average coherence between the conditions (p<0.05). Action observation application with FES in all frequency band showed the highest peak and average coherence value. Conclusions: The results of this study are assumed to be the combination of increased eccentric information transfer from the sensorymotor cortex by action observation and an increased in concentric sensory input from the peripheral by the FES, suggesting that these are reflecting the sensorimotor integration process.

• 한국실내디자인학회논문집
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• 제20권6호
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• pp.183-191
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• 2011

This study is to set up the appropriate range of observation time through contemplating the characteristics of observation time run for the information acquisition of space. The conclusions reached through this study are as the followings. First, this study could find out that even though the evaluation elements on the three types for image evaluation were the same, the information acquisitions were different as those types varied. On the other hand, the change of the average run-time by type for the information acquisition was found not to be big, in other words, even though the run-time was alike, the information acquisitions varied depending on the type. Second, he evaluation by language media showed the average value by element had the order of [shape>position>number>existence] and the range of their run-time was 94.6~102.9 seconds. The average rate of information acquisition shown at the visual media had the order of [composition>shape>material&color] and the range of run-time was 93.1~99.7 seconds. Third, the evaluation by language media showed that for male subjects the range of information acquisition rate was 39.1~91.4% and that of run-time 85.1~106.0 seconds and for female ones 46.0~94.6% and 96.3~112.3 seconds respectively. In case of the visual media, male subjects showed the range of information acquisition rate was 40.3-66.7% and the range of run-time 82.4~97.9 seconds and the female ones, 42.2~71.0% and 94.0~115.1 seconds respectively, through which we could see that at the evaluation by language media and visual media both the female's range of information acquisition and that of observation time were higher than the male's.

• 재활치료과학
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• 제5권1호
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• pp.55-65
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• 2016

목적 : 본 연구의 목적은 가정-기반 동작관찰 훈련이 뇌종양 환자의 상지기능에 미치는 영향을 알아보기 위함이다. 연구방법 : 단일사례연구 방법 중 ABA 디자인을 사용하였다. 기초선(A) 기간에 중재 없이 4회 평가를 실시하였고, 중재선(B) 기간에 총 25회의 훈련과 10회 평가를 실시하였으며 중재 후 회귀기초선(A') 기간에 중재 없이 4회 재평가를 실시하였다. 결과 : 9-홀 페그 테스트, 상자와 나무토막 검사, 뇌졸중 상지 기능검사에서 뇌종양 환자의 상지기능이 기초선과 회귀기초선(A와 A')보다 중재기(B)에 개선되었다. 세계보건기구 삶의 질 척도의 신체적 영역, 심리적 영역, 생활환경 영역에서 점수 향상이 있었다. 결론 : 본 연구 결과로 동작관찰 훈련이 뇌종양 환자에게 적용 가능한 중재 기법이고 상지 기능과 삶의 질을 향상시킨다는 것을 알 수 있었다.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제23권3호
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• pp.149-164
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• 2020

This study aimed to establish an observation protocol for mathematical modeling as an alternative way to examine instructional alignment to the Common Core State Standards for Mathematics. The instructional alignment observation protocol (IAOP) for mathematical modeling was established through careful reviews on the fidelity of implementation (FOI) framework and prior studies on mathematical modeling. I shared the initial version of the IAOP including 15 items across the structural and instructional critical components as the FOI framework suggested. Thus, the IAOP covers what teachers should do and know for practices of mathematical modeling in classrooms and what teachers and students are expected to do. Based on the findings in this study, validity and reliability of the IAOP should be evaluated in follow-up studies.

• 한국정보전자통신기술학회논문지
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• 제15권2호
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• pp.103-108
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• 2022

광각 카메라 시스템으로 획득한 전천 영상을 이용한 구름 관측은 21세기 초반부터 다양한 연구가 진행되었으나 목측을 완벽하게 대체할 자동 관측 시스템은 얻지 못하였다고 판단된다. 본 연구는 목측의 자동화를 목표로 제안한 알고리즘의 최종 단계인 구름 관측의 정량화를 검증하기 위하여 전천 영상과 보정 영상의 구름 분포를 비교 분석하였다. 그 이유는 구름은 종류에 따라 일정한 높이에 형성되고, 전천 영상은 망막의 영상처럼 렌즈의 중심부는 확대되고 가장자리는 축소되지만, 인간의 학습 능력과 공간 인지 능력 등이 구름 관측에 미치는 영향은 알려진 바가 없기 때문이다. 본 연구 결과는 전천 영상과 보정 영상의 구름 관측 오차가 평균은 1.23%였다. 따라서 10분위 또는 10단계로 관측되는 목측과 비교하면 보정에 의한 오차는 관측량의 1.23%로 목측의 허용 오차보다 매우 적을뿐만 아니라 인간의 실수를 포함하지 않으므로 정확히 정량화된 데이터의 수집이 가능함을 확인하였다. 또한 보정에 의한 운량의 변화가 미미하므로, 불필요한 보정 단계를 생략하고 보정 이전의 전천 영상에서 운량을 관측하여도 정확한 관측치를 얻을 수 있음을 확인하였다.

• 한국멀티미디어학회논문지
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• 제22권12호
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• pp.1430-1437
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• 2019

In this paper, we proposed a methodology for estimating rainfall intensity using a W-band FMCW automotive radar signal which is the core technology of autonomous driving car. By comparing and analyzing the results of rainfall and non-rainfall observation, we found that the reflection intensity of the automotive radar is changed with rainfall intensity. We could confirm the possibility of deriving the quantitative precipitation estimation using the methodology derived from this result. In addition it can be possible to develop a new paradigm of precipitation observation technique by observing various events together with the weather radar and the ground rainfall observation equipment.

• Communications for Statistical Applications and Methods
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• 제20권4호
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• pp.283-290
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• 2013

Subjects can experience two types of recurrent events in a longitudinal study. In addition, there may exist intermittent dropouts that results in repeated observation gaps during which no recurrent events are observed. Therefore, theses periods are regarded as non-risk status. In this paper, we consider a special case where information on the observation gap is incomplete, that is, the termination time of observation gap is not available while the starting time is known. For a statistical inference, incomplete termination time is incorporated in terms of interval-censored data and estimated with two approaches. A shared frailty effect is also employed for the association between two recurrent events. An EM algorithm is applied to recover unknown termination times as well as frailty effect. We apply the suggested method to young drivers' convictions data with several suspensions.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2010년 춘계학술발표회 논문집
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• pp.187-190
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• 2010

GPS survey came into wide use, but there are inefficient parts in related laws and regulations. Especially, to get GPS surveying results under 1.5cm permissible error the observation time must be longer than 8 hours in triangulation points surveying regulations. However, GPS surveying technology is developing now, so results could be acceptable under 4 hours observation time. Therefore, this study made a stable standard of observation time in GPS survey by comparing the errors due to observation time, and used PAJU, DOND and YANP's GPS data and 6 cadastral points' survey data. Also, to analyze the variations of results due to baseline distance, applied each GPS site as a fixed point and compared the positions. As a result, the stable satisfactory results were calculated under 4 hour survey, when the baseline distances were under 30km.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.162-164
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• 2003

The multi-disciplinary research project Strengthening Local Authorities in Risk Management (SLARIM), initiated by ITC, includes three case study cities in Asia. An important question is: what are the essential data for risk management and how to access such data. The role of common sources (e.g. census data), data derived from remote sensing (high-resolution satellite imagery, aerial photos), and data from close sensing (field observation, including mobile GIS) to acquire essential risk management data will be discussed. Special attention is given to the question of the minimum area and to disaggregating population data. A few examples are given of Kathmandu / Lalitpur, Nepal.