학생의 성격 유형을 고려한 초등 과학 모둠 활동에서 창발성 발현 사례 분석

지광훈 ( Kwang-hoon Ji ),임채성 ( Chae-seong Lim ),김재영 ( Jae-young Kim ) 韓國生物敎育學會 2017 생물교육 Vol.45 No.1

The present study was designed to examine the effects organization of small groups according to the student`s personality types on elementary science learning and emergent properties. Emergent property is defined as a phenomenon whereby novel entities arise through interactions among component entities such that the novel entities exhibit properties the component entities do not exhibit. The sample was composed of 20 students in Grade 4 at `G` elementary school in Seoul. The three groups were formed as introvert, extrovert, and introvert/extrovert (mixed) groups according to student`s personality types. During the cooperative activities, a series of data were obtained and compared in terms of expression of emergent properties. The discourses occurred within each group were recorded and the interviews were performed and analyzed in an attempt to see how the way of organization of groups according to student`s personality types and the cooperative activities in science are interrelated. The students of extrovert group presented quickly and actively new alternatives in the situations of opinion disagreement. And the opinions of the students with poor peer relationships were often ignored in cooperative processes. The introvert group seldom expressed active interaction and so emergent properties. Also, the introvert leaders in the introvert/extrovert groups didn`t induce emergent properties a lot. The introvert group showed distribution type of cooperative learning. On the other hand, the extrovert group showed the emergent type of cooperative learning more frequently. The present study concludes that we should consider the personality types and peer relations of the students in designing and executing the cooperative learning in the elementary school science.

한국 증권시장의 주가 급등락과 주가 반등

지광훈(Kwang-Hoon Ji),정종락(Jong-Rock Chung) 연세대학교 경영연구소 2007 연세경영연구 Vol.44 No.2

본 연구는 주가 급등락의 충격 이후 나타나는 주가의 이상반응 현상을 한국의 주식시장을 대상으로 실증적으로 검증하였다. 1998년부터 2004년까지의 한국 증권선묻거래소 상장 주식의 일별수익률 자료를 이용하여 주가 급등락 이후의 전제표본, 상승추세 표본, 그리고 하락추세 표본의 주가 반응을 조사했다. 일별 10% 이상의 급등락 충격 이후 3일간의 누적초과수익률의 반응에 기초한 실증 분석의 결과는 다음과 같다. 첫째, 한국 주식시장에는 주가 급등의 충격 직후에는 양(+)의 초과수익을 발생시켜 모멘텀현상을 보이는 것으로 나타났다. 그러나 급등과 달리 급락 충격 직후에는 통계적으로 유의한 초과수익이 발생하지 않아 이상반응을 보이지 않는 것으로 나타났다. 둘째 투자자의 사전적 인식이 주가 급 등락과 함께 고려되는 경우에 상승 추세에서의 주가 급등 경우와 하락 추세의 주가 급등 경우에는양(+)의 초과수익을 발생시키고 있으나 그 이외의 경우는 이상 반응이 나타나지 않았다. 이는 급락의 경우에도 양(+)의 초과수익이 발생하여 반전현상을 보인 미국주식시장을 대상으로 조사한 선행 연구와 다른 결과이다. 셋째, 주가 급등락의 크기와 이후 이상 반응의 정도와의 관계는 예상대로 대제로 정(+)의 상관 관계가 있는 것으로 나타났다. The analysis is mainly focused on the price behaviors of Korean stock market following large one day price shock. These responses are differently related to the direction of the price shock and to pre-shock stock return drifts and firm fundamental characteristics. We analyze the relationship based on the Behavioral Finance hypotheses. Using daily returns for 141 companies from the KOSPI 200 index from March 1998 to December 2004, we use event study methodology to test the relationship between pre-shock variables, stock return drifts and firm fundamental characteristics, and post-shock cumulative abnormal returns. The large one day price shock defined as a change of at least 10%. The empirical results of this study are as the followings. First, the positive price shock shows positive cumulative abnormal returns in the Korean Stock Market, implying that there is the momentum. But there is not an distinct response following the negative price shock. Second, considering the direction of the price shock and pre-shock variables together, there are positive cumulative abnormal returns following the positive price shock from uptrend or downtrend. This empirical result is different from the results in the United States stock market. Third, the magnitude of the price shock is positively related to the post response.

"식물의 세계" 단원 학습에서 초등학생의 성격유형을 고려한 모둠 구성이 과학 태도, 과학 탐구 기능, 과학 지식에 미치는 효과

지광훈 ( Kwang Hoon Ji ),임채성 ( Chae Seong Lim ),김재영 ( Jae Young Kim ) 한국생물교육학회 2014 생물교육 Vol.42 No.4

This study was designed to examine students`` science learning according to their personality types. The sample was composed of 20 students in Grade 4 at ``G`` elementary school in Seoul and the topic of learning was World of Plants. The introvert, extrovert, and mixed groups were formed according to students`` personality types. During the cooperative learning, a series of data were obtained and compared in terms of scientific attitude, scientific inquiry skill and scientific knowledge. The discourses among students were recorded and the interviews with them were performed and analyzed in an attempt to examine how the ways of organizing groups according to students`` personality types and the science learning are interrelated. The results of this study were as follows: First, the scores of introvert students on positiveness and cooperative mind were lower than those of extrovert ones. Second, only scientific attitude of extrovert group has significantly improved in the cooperative learning process. Because the extrovert team presented quickly new alternatives in the situations of opinion disagreement. And the opinions of the students with poor peer relationships were often ignored in cooperative learning process. The present study concludes that we should consider the students`` personality types and peer relations in designing and executing the cooperative learning in the elementary school science.

위성영상과 음영기복도를 이용한 오대산 지역 진앙의 위치와 선구조선의 관계 분석

차성은 ( Sung-eun Cha ),지광훈 ( Kwang-hoon Chi ),조현우 ( Hyun-woo Jo ),김은지 ( Eun-ji Kim ),이우균 ( Woo-kyun Lee ) 한국지리정보학회 2016 한국지리정보학회지 Vol.19 No.4

본 연구에서는 LANDSAT 8호, KOMPSAT 2호 위성영상과 1/25,000 수치지형도를 기반으로 작성된 음영기복도를 이용하여 2007년 1월 20일 오대산 지역에서 발생한 약 4.8의 중규모 지진과 선구조선의 관계를 분석하였다. 대부분의 선행연구는 지체구조와 관련된 선구조선 분석 연구를 하였으며, 주로 2차원의 위성영상과 음영기복도를 활용하였기에 지형의 기복 등에 대한 판독이 어려워 선구조선 추출이 제한적이었다. 본 연구에서는 이를 보완하기 위해 수치표고모델(Digital Elevation Model; DEM)을 기반으로 작성한 3차원 입체 영상과 수계망 분석을 통해 지형의 기복, 수계의 연결성 등을 판독해 선구조선을 추출하여, 2차원 영상에서 나타나는 시각적인 판독에 의한 오류를 최소화한 선구조선 판독도를 작성하였다. 또한 진앙에 대한 선구조선의 통계 요소별 밀도를 추정하기 위해 spline 내삽법을 이용하여 선구조선의 빈도, 교차점, 길이에 대한 밀도를 계산하였다. 그리고 진앙에서의 선구조선 밀도가 얼마나 밀집되어 있는지 정량적으로 표현하기 위하여 각 격자 내의 선구조선 밀도에 대해 최대 선구조선 밀도로 나누는 상대밀도 값(Value of the Relative Density; VRD)을 계산하는 알고리즘을 개발하여 밀도도(density map)를 작성하였다. 각 영상의 진앙에서의 VRD는 최소 약 0.60에서 최대 약 0.90으로 나타났지만, 각 영상별 광원의 고도각과 방위각이 차이가 있어 영상별 VRD보다 통계 요소별 VRD의 평균치를 사용하였다. 그 결과, 빈도의 평균 VRD는 약 0.85로 교차점과 길이의 평균 VRD보다 약 21% 높게 나타나, 선구조선의 빈도 요소가 진앙의 위치와의 관계가 가장 밀접함을 확인하였다. 이와 같이 3차원 영상의 선구조선 추출을 통한 밀도 분석 기술은 향후 지진 발생 가능 지역 분석에 기초자료로써의 의미가 있을 것으로 기대된다. The purpose of this paper is to analyze the relationship between the location of the epicenter of a medium-sized earthquake(magnitude 4.8) that occurred on January 20, 2007 in the Odaesan area with lineament features using a shaded relief map(1/25,000 scale) and satellite images from LANDSAT-8 and KOMPSAT-2. Previous studies have analyzed lineament features in tectonic settings primarily by examining two-dimensional satellite images and shaded relief maps. These methods, however, limit the application of the visual interpretation of relief features long considered as the major component of lineament extraction. To overcome some existing limitations of two-dimensional images, this study examined three-dimensional images, produced from a Digital Elevation Model and drainage network map, for lineament extraction. This approach reduces mapping errors introduced by visual interpretation. In addition, spline interpolation was conducted to produce density maps of lineament frequency, intersection, and length required to estimate the density of lineament at the epicenter of the earthquake. An algorithm was developed to compute the Value of the Relative Density(VRD) representing the relative density of lineament from the map. The VRD is the lineament density of each map grid divided by the maximum density value from the map. As such, it is a quantified value that indicates the concentration level of the lineament density across the area impacted by the earthquake. Using this algorithm, the VRD calculated at the earthquake epicenter using the lineament``s frequency, intersection, and length density maps ranged from approximately 0.60(min) to 0.90(max). However, because there were differences in mapped images such as those for solar altitude and azimuth, the mean of VRD was used rather than those categorized by the images. The results show that the average frequency of VRD was approximately 0.85, which was 21% higher than the intersection and length of VRD, demonstrating the close relationship that exists between lineament and the epicenter. Therefore, it is concluded that the density map analysis described in this study, based on lineament extraction, is valid and can be used as a primary data analysis tool for earthquake research in the future.