• 한국수학교육학회지시리즈D:수학교육연구
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• 제16권4호
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• pp.217-232
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• 2012

While many studies on early algebra have been conducted, there have been only a few studies on the operation sense as the fundamental element of algebraic thinking, especially the fraction operation sense. This study explored the dimensions of fraction operation sense and then investigated students' fraction operation sense. A total of 183 of sixth graders were surveyed and 5 students who showed high operation sense were clinically interviewed in order to analyze their algebraic thinking in detail. The results showed that students had a tendency to use direct calculation or employ inappropriate operation sense rather than to use the structure of operation or the relation between operations on the basis of algebraic thinking. This study implies that explicit instruction on early algebra is necessary from the elementary school years.

• 한국임상수의학회지
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• 제34권3호
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• pp.218-221
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• 2017

A 14-year-old castrated Shih Tzu weighing 5.4 kg presented with painful penile erection and dysuria that had been ongoing for 2 days. Treatment with salbutamol and gabapentin was initiated, but after 24 hours, the dog had not responded, so it was decided to proceed with penile amputation. The patient went into cardiac arrest during the surgery and died, despite attempted cardiopulmonary resuscitation. During the surgery, the penis was found to have an enlarged, tortuous, purple blood vessel located dorso-caudally to the bulbus glandis. A hemi-circular fibrous mass was found inside the vessel on histopathological examination; this mass may have induced the ischemic priapism by occluding the vein. This report describes a rare case of ischemic priapism in dogs.

• The Korean Journal of Ceramics
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• 제3권3호
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• pp.213-217
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• 1997

In this paper, the imparct of X-ray and plasma process-induced-damages to La doped Lead Zirconate Titanate (PLZT, (Pb1-xLa)(Zr0.5Ti0.5)O3) capacitor characteristics have been investigated from the viewpoint of gigabit scale dynamic random access memory (DRAM) applications. Plamsa damage causes asymmetric degradation on hysteresis characteristics of PLZT films. On the other hand, X-ray damage results in a symmetrical reduction of charge storage densities (Qc's) for both polarities. As La concentration increases in the films, the radiation hardness of PLZT films on X-ray and plasma exposures is improved. It is observed that the damaged devices are fully recovered by thermal annealing under oxygen ambient.

• 한국컴퓨터정보학회논문지
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• 제22권10호
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• pp.73-81
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• 2017

In this paper, we propose an analysis framework to capture the trends of information security incidents and evaluate the security policy based on the incident analysis. We build a big data from news media collecting security incidents news and policy news, identify key trends in information security from this, and present an analytical method for evaluating policies from the point of view of incidents. In more specific, we propose a network-based analysis model that allows us to easily identify the trends of information security incidents and policy at a glance, and a cosine similarity measure to find important events from incidents and policy announcements.

• Journal of Magnetics
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• 제19권2호
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• pp.146-150
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• 2014

The objective of this paper is to provide a comparison between two transverse flux rotary machines (TFRM) with different topologies of stator cores. Depending on how to make stator core with laminated steel sheets, the one topology is 'perpendicular stacking core' and the other is 'separated core'. Both of the two cores have been designed considering 3-dimensional (3-D) magnetic flux path with the same output power conditions, but the core losses are quite different and it causes different magnetic and thermal characteristics. For comparison of these two topologies of stator cores, therefore, core losses have been calculated and used as a heat source in no-load conditions, and the thermal stress has been also calculated. 3-D finite element method has been used for the magnetic field, thermal, and stress analysis to consider the 3-D flux path of the TFRM. After comparing the analysis results of the two topologies, experimental results are also presented and discussed.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2001년도 추계정기 학술발표회 초록집
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• pp.16-16
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• 2001

• Bulletin of the Korean Chemical Society
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• 제35권2호
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• pp.345-346
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• 2014

• 한국컴퓨터정보학회:학술대회논문집
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• 한국컴퓨터정보학회 2018년도 제58차 하계학술대회논문집 26권2호
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• pp.515-516
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• 2018

본 논문에서는 수동 적외선 (PIR: passive infrared) 센서를 탑재한 센싱 시스템과 딥러닝 알고리즘을 활용하여 실내 환경에서 사용자의 이동 방향을 인식하기 위한 방법을 제안한다. PIR 센싱 소자는 사람의 이동 방향에 따라 구별이 가능한 신호를 발생시키는데, 4개의 PIR 센서를 $45^{\circ}$씩 증가하도록 배치한 센싱 시스템을 개발하여 실내 천장에 설치한 뒤 6명의 사용자로부터 인식 범위 내에서 움직이는 동안 PIR 센서 신호를 수집하였다. 수집한 원시 데이터와 특징 데이터를 추출하여 딥러닝 알고리즘을 적용한 인식률을 실험하였으며, 제안한 센싱 시스템과 딥러닝 알고리즘이 사용자의 움직임을 99.2%%로 인식할 수 있음을 보였다. 또한 한 개의 센서만을 이용하였을때에도 98.4%의 정확도로 사용자의 움직임 방향을 탐지하였다.

• Archives of Pharmacal Research
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• 제28권8호
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• pp.885-888
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• 2005

Jacaranone and related compounds (1-3) were isolated, along with three triterpenes (4-6), from the fresh fruits of Ternstroemia japonica. The compounds were identified as jacaranone (1), 3-hydroxy-2,3-dihydrojacaranone (2), 3-methoxy-2,3-dihydrojacaranone (3), 3-O-acetyl­oleanolic acid (4), 3-O-acetylursolic acid (5), and ursolic acid (6). Jacaranone and its derivatives were isolated for the first time from Theaceae. Of the isolated compounds, compound 3 is a new compound. Jacaranone (1) exhibited weak antioxidative effect on 1, 1-diphenyl-2-picryl-hydrazyl (DPPH) radical.

• 아동학회지
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• 제36권5호
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• pp.19-36
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• 2015

The purpose of this study was to firstly, investigate the relationship between infants' communicative gestures, play and maternal responsiveness and secondly, to examine the role of maternal responsiveness in the associations between infants' communicative gestures and play. The subjects comprised 42 infants (21 boys and 21 girls) and their mothers. The infants' communicative gestures, the infants' play and maternal responsiveness were observed during free play sessions lasting 20 minutes. The results are as follows. Mothers of girls showed higher levels of responsiveness than the mothers of boys. In addition, here were positive correlations between infants' communicative gestures, play and maternal responsiveness. Maternal responsiveness was observed to moderate the effects of infants' communicative gestures on the infants' average level of play. These results indicate that it is important for caregivers to interpret infants' communicative intentions appropriately and respond promptly and adequately in play situations.