• Title/Summary/Keyword: 집단 구조

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Ecosystem Risk Assessment Using the Indicator Species (지표종을 이용한 생태계 위해성평가)

  • Chang, Jin-Soo;Kim, Kyoung-Woong
    • Journal of Soil and Groundwater Environment
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    • v.12 no.1
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    • pp.103-115
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    • 2007
  • Risk assessment by living indicator species provides the information about the ecosystem disturbance, disapperance of symbiosis and change of living group. In the initial stage of this kind research, the degree of contamination was reported using the level of simple number, but simple number may not represent the risk itself which can be casued in the living organisms. Risk assessment using various indicator species overcomes these limitations and can be expanded to the DNA level. In many developed counties, the government has supervised the researches about the indicator species for the monitoring and its application to ecosystem restoration. Several living indicator species found in the vicinity of the abandoned Au mines such as fern, earthworm, bacteria, rhizosphere-rhizoplane, salamamdor and DNA change of these species are described in this paper.

Mathematical Reasoning Ability and Error Comparison through the Descriptive Evaluation of Mathematically Gifted Elementary Students and Non-Gifted Students (초등수학영재와 일반학생의 서술형 평가를 통한 수학적 추론 능력 및 오류 비교)

  • Kim, Dong Gwan;Ryu, Sung Rim
    • Journal of Elementary Mathematics Education in Korea
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    • v.18 no.1
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    • pp.123-148
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    • 2014
  • The purpose of this study is to figure out the perceptional characteristics of mathematically gifted elementary students by comparing the mathematical reasoning ability and errors between mathematically gifted elementary students and non-gifted students. This research has been targeted at 63 gifted students from 5 elementary schools and 63 non-gifted students from 4 elementary schools. The result of this research is as follows. First, mathematically gifted elementary students have higher inductive reasoning ability compared to non-gifted students. Mathematically gifted elementary students collected proper, accurate, systematic data. Second, mathematically gifted elementary students have higher inductive analogical ability compared to non-gifted students. Mathematically gifted elementary students figure out structural similarity and background better than non-gifted students. Third, mathematically gifted elementary students have higher deductive reasoning ability compared to non-gifted students. Zero error ratio was significantly low for both mathematically gifted elementary students and non-gifted students in deductive reasoning, however, mathematically gifted elementary students presented more general and appropriate data compared to non-gifted students and less reasoning step was achieved. Also, thinking process was well delivered compared to non-gifted students. Fourth, mathematically gifted elementary students committed fewer errors in comparison with non-gifted students. Both mathematically gifted elementary students and non-gifted students made the most mistakes in solving process, however, the number of the errors was less in mathematically gifted elementary students.

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Study of the Ecosystem Model of Magazine on Special Genre Focusing on Collaboration System within Magazine Firm, Community and Creative User (전문잡지의 생태계 모델 분석 - 잡지사·커뮤니티·사용자의 협업체계를 중심으로)

  • Chang, Yong Ho;Kong, Byoung-Hun;Jin Jeon, Eun-Young
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.8
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    • pp.4831-4843
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    • 2014
  • Magazines on specific genres have been operating collaborative, co-working and collective production systems for value maximization using an adaptation strategy on the dynamic, complex and uncertain value network of the magazine industry. The study used a case study method, and data collection was performed by observational research, depth interviews and survey research. The subjects of the study were 'magazine industry', 'magazine firm and community', and 'collaboration system within creative users'. According to the research results, the ecosystem of magazines on a specific genre has been evolving into an innovative value network system, which is combined with the magazine firm, community users and magazine platform. Second, the rapid introduction of smart device environment changes the way of the collaborating system, in which an action and interaction came out within the community, creative users and magazine firms. Third, the production agency shows strong action and interaction, which fits the magazine platform within the ecosystem of a magazine on a specific genre well. This model has a similar fractal structure to the game, publishing, drama, movie, comic, and animation contents industry, converging to an innovative technology-based-creative-industry.

Effects of Cooperative Learning Strategy on Achievement and Science Learning Attitudes in Middle School Biology (협동학습 전략이 중학교 생물학습에서 학생들의 학업성취도와 과학에 대한 태도에 미치는 영향)

  • Chung, Young-Lan;Son, Dae-Hee
    • Journal of The Korean Association For Science Education
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    • v.20 no.4
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    • pp.611-623
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    • 2000
  • The cooperative learning movement began as parts of the desegregation process in America, aiming at increasing academic achievement and social skills among diverse students. Cooperative learning may be defined as a classroom learning environment in which students work together in small heterogeneous groups. Although many studies have shown the effectiveness of cooperative learning in a variety of subjects, relatively few have focused on biology. In this study, we investigated the effects of cooperative learning on students' achievement and attitude of middle school biology students. For this purpose this study compared three sections. In one section, a cooperative learning strategy was used. Second section was taught in small groups and the third section was instructed in the traditional method. The unit 'Structures and functions of animals' was used. A total of 188 students were included in this study. These classes were treated for 10hours during 10weeks from September 1 to November 28, 1999. The pretests-posttests control group design was applyed. An analysis of covariance(ANCOVA) was used as the data analysis procedure. Significant differences were found in the achievement and the attitude of students using cooperative learning strategy(p<.05) when compared to traditional classroom structure and small group learning. Cooperative learning was more effective in the low-ability and average-ability students than the high-ability students in the science achievement. Cooperative learning is effective in both male and female students. And students in the cooperative group achieved better than those in other groups in affective, behavioral, and intention-cognitive domain of science attitude.

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An Analysis of the Verbal Interaction Patterns of Science-Gifted Students in Science Inquiry Activity (과학 탐구 활동에서 나타나는 과학영재들의 언어적 상호작용 유형 분석)

  • Kim, MyungHee;Kim, Youngshin
    • Journal of The Korean Association For Science Education
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    • v.35 no.2
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    • pp.333-342
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    • 2015
  • This study analyzes the verbal interaction patterns used in a social network activity analysis that appeared in a science inquiry activity of 31 small groups of science-gifted students consisting of 5 members each. The results of this study are as follows: The interaction patterns showed eight types. The most prevalent interaction pattern, type 1, is triangle-shaped, interacting with 3 members out of 5 without a central member. Type 2 is wye form, interacting with 4 members and with one alienated member. Type 3 is diamond-shaped, interacting with 4 members. Type 4 is ray form, interacting with 5 around a central member. Type 5 has an alienated member and interacts with 4 members around the central member. Type 6 is triangle-branched, 4 members linked to the central member. Type 7 is wye form linked all around the central member. Type 8 is wye form with a more complex link than type 7. These can be classified in two. One is the participation-type where the rest of the 4 members are linked to the central member. The other is the alienation-type where a member/members is/are alienated without a central member. The participation-type appeared in 9 groups (29%), type 4, type 6, type 7, and type 8. The alienation-type showed in 22 groups (71%), type 1, type 2, type 3, and type 5. On the basis of this study, we propose that the best number of members in a group is three. It helps prevent a free-riding effect or isolation of members. Also, we deem it more fruitful if there is a member playing a central role in a group.

A Case Study on the Features of Classroom Norms Formed in Inquiry Activities of Elementary Science Classes (초등학교 과학 수업의 탐구활동에서 형성되는 교실 규범의 특징에 대한 사례 연구)

  • Chang, Jina;Song, Jinwoong
    • Journal of The Korean Association For Science Education
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    • v.35 no.2
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    • pp.303-312
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    • 2015
  • The purpose of this study is to analyze classroom norms formed in inquiry activities of elementary science classes and to consider about the actual problems in enacting school science inquiry. Focusing on the inquiry activity cases of two classes, the data were collected through classroom observation, student interview, teacher interview and questionnaires. Firstly, classroom norms were categorized into three categories theoretically: norms for behavior guidance; general academic norms; and scientific inquiry academic norms. The subcategory norms of each category were extracted inductively and the features, the causes of formation, and the influences on inquiry of each norm were also analyzed. Based on the analyses on classroom norms, the researchers identified three actual problems in enacting school science inquiry. First, the collective traits of school science inquiry caused structural problems in science classrooms. Second, teachers used their authorities in different ways according to phases of instructions. Third, the conflict cases were reported between general values for education and specific values for science inquiry. Educational implications are discussed in terms of the practices of school science inquiry and of the understanding classroom phenomena.

전자파의 신경계통에 대한 영향

  • 이근호
    • The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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    • v.8 no.2
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    • pp.37-55
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    • 1997
  • 최근 선진국가들에서는 전자파 장애 증후군에 관심이 집중되고 있는데, 전자파에 장기 노출 되는 인구에서 뇌암이나 유방암, 백혈병 등의 발생률이 높다는 보고(Kolmodin-Hedman 등, 1988 ; Demers등, 1991)가 있어서 전자제품의 생산업체는 물론이고 사용자에 대해서도 불안한 관심사가 되 어 있다. 전자파가 생체에 미치는 영향은 열적 효과와 비열적 효과에 의한 것으로 구분된다. Microwave는 약 300MHz에서 300GHz 사이(파장 1m에서 1mm사이)의 주파수를 가지는 전자파로서 이온의 운동이나 쌍극자분자(dipole molecule)들을 진동시키므로서 조직에 열이 발생한다. 열이 과도하게 발생하면 세포 단백질이 응고하게 되는 등 일반적으로 생각할 수 있는 고열로 인한 여러 가지 유해환경이 조직 에 조성될 수 있다. 실제로 고전압의 전자파에 노출된 안구의 수정체에 백내장 등의 병변이 발생한 것 으로 보고된 바 있다(Adey,1981). 일반적으로 전자파의 생체에 대한 작용으로는 이렇듯 조직에 흡수 되는 전자파의 에너지에 의한 열작용이 지배적인 것으로 생각되어 왔다. 그러나 초저주파역대(Extre- mely low frequency, EMF)의 변조 및 펄스파 등의 영향에 관해서도 조직의 온도상승으로는 설명할 수 없는 현상이 보고된 바 있다. 이러한 비열적 효과가 신경계에 끼치는 영향에 대해서는 혈액뇌관문 의 투과성 변화(Oscar와 Hawkins, 1977), 뇌종양 발생, 칼슘대사 이상 및 신경전달물질에 대한 영향 등이 주장(Anderson, 1993)되고 있으나 아직 그 분명한 기전이 밝혀져 있지 않은 상태이다. 또한 그 영향의 평가에 서도 일정한 기준이나 지표가 정해지지 않은 실정이다. 그러므로 신경계에 대한 대체적인 소개와 더불어 전자기파의 영향에 대한 이제까지의 보고를 종합 하고 향후 연구의 방향을 소개하고자 한다.> 이온이 공동 첨가제로 더 적합하다.u(30 .angs. )/CoFe(35 .angs. )/NiO(800 .angs. ) 구조를 갖는 spin-valve 박막은 극대 MR비 6.3%, 유효자기장감응도 약 0.5(%/Oe)를 보여 spin-valve head 재료로 적합함을 알 수 있었다.다.다.다.는 각각 148 meV .angs. $^{2}$, 103.8 meV .angs. $^{2}$와 1.77 * $10^{-6}$ erg/cm, 0.67 * $10^{-6}$ erg/cm 였다.다.자 노인들을 영주권자와 귀화 시민권자의 구분없이 하나의 집단으로 간주하고 분석해 왔던 것을 볼 때, 앞으로의 연구는 이론적으로나 방법론적으로 시민권의 유무가 주거형태에 끼치는 영향도 함께 고려해야 할 것이다.에 나타난 인도의 영향은 여성복식과 남성복식에 있어서 서로 유사점과 차이점이 보이는데, 인도의 영향이 여성복식에 있어서 그 빈도가 더 높고, 종류가 더 다양함을 볼 수 있다. 여성복식에 있어서는 12가지의 다양한 인도복식스타일이 나타났으며, 그중 가장 많이 보이는 스타일은 Indian Shirt/Blouse/Smock/ Dress이며, 그 뒤를 이어 Madras, Indian lowery등을 볼 수 있다. 남성복식애 나타난 7가지의 스타일 중에는 Madras가 가장 빈도가 높으며 그외의 스타일들은 그 빈도가 매우 낮음을 볼 수 있다. 인도의 영향의 정도 (Attribution Categories) 있어서는 여성과 남성복식 모두에 있어서 인도에서 직접 수입된(originated) item이 각각 전체의 90%와 81%를 차지하여, 인도복식의 영향은 받았으나 미국내에서 제작된(attributed and connotated) item 보다 휠씬 더 많은 수를 보였다. 인도복식스타일이 가장

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The Effects of Demographic Factors on the Change of Female Labor Market (여성인구변동과 노동시장)

  • Chang, Ji-Yeun
    • Korea journal of population studies
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    • v.21 no.2
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    • pp.5-36
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    • 1998
  • This study examines the change of female labor market structure during the last several decades, focusing the effects of demographic factors such as declining fertility and increasing educational attainment of women. Women of the recent cohort tend to postpone their first marriages, to attain higher levels of education, and to have smaller number of children than women of the old cohort. This demographic trend results in the change of the population compositions in a way that population subgroups with high labor force participation have been increased. In addition, women of each population subgroup supply their labor in the market with higher rate than their old cohort counterparts. The labor force participation rate of highly educated women, and of married women has been increased faster than that of women with low education and of unmarried women. Although childbirth is still one of the most critical barrier for the women's participation, more and more women with young children tend to work for pay than ever before. In spite of the demographic change which is supportive to the increasing labor force participation, the Korean labor market have lost its female participants for the last year of the economic restructuring, reflecting demand-side factors as well as demographic factors are essential to determine the labor force participation of women.

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The Impact of Clothings of Kisaengs in the later Choson (조선후기의 기녀 복식이 사회에 미친 영향)

  • Kim, Hye-Young
    • The Journal of Natural Sciences
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    • v.8 no.2
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    • pp.289-321
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    • 1996
  • After the two big wars (Imjin Woeran and Byungia Horan), the Lee Dynasty confronted rapid transitional periods in almost all aspects of the society. Corruption of the governmental system by the wars and disordered social structures also caused confusion in the social position system. In addition, development of the commercial economic system and monetary economy brought up a new rich middle-class, "Joong in Gyegeup". In ideological aspects, Confucianism indulged in and stick to isms and ics, and the Confucian morality slackened, thus a more pragmatic ideology, "Silhak Sasang", developed. And the emergence of the modern literature and art of the 'common people' was followed by the appearance of the common-people class including those having the common-people concept among the noble-class "Yangban Gyegeup". This evoked a new common costume culture and the fashion appeared. The public could no longer find the power and appeal from the preexisting ruling classes due to the changed role and sense of value. Thus, they sought a new symbolic leader group that would to be the new standard of the newly changed society. That was a group of people called as "Kisaeng" liberal and independent. They were performing social activities, enjoying poetry, music and dancing, and classy dressers, having physically attractive bodies. The erotic as well as luxurious mode proposed by them reflected the trend of that time. It concurred well with the concept and taste of the public, so it was accepted with a good response. That is, by following these leaders, the public achieved their identification and tried to share the prestige of the leaders. For this reason, the Kisaeng group attracted the public attention and led the taste of the public, thereby becoming the influential fashion leaders of that age.

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Notes on fine-scale spatial distribution of three Cephalanthera species (Orchidaceae) that grow in sympatry in Korea: Implications for maintenance of species boundaries (동소적으로 서식하는 은대난초속 3종(난과)의 미세 공간 분포에 대한 참고 사항: 종의 경계 유지에 대한 암시)

  • Chung, Mi Yoon;Lopez-Pujol, Jordi;Chung, Myong Gi
    • Korean Journal of Plant Taxonomy
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    • v.47 no.4
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    • pp.289-296
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    • 2017
  • The three self-compatible, terrestrial orchids Cephalanthera erecta, C. falcata, and C. longibracteata flower synchronously in sympatric populations. Cephalanthera erecta and C. longibracteata, which have white flowers that do not fully open, are predominantly autogamous, whereas the food-deceptive C. falcata, whose bright yellow flowers open completely, is predominantly outcrossing. The formation of hybrids rarely occurs between species owing to strong prepollination barriers (floral isolation). If these three species have evolved toward the prevention of interspecific hybridization, we can expect that the spatial distribution patterns of the three species would be characterized as spatial segregation (i.e., 'spatial repulsion') from each other. To test this prediction, we studied the three Cephalanthera species in sympatric populations showing coincident flowering within Yeonwhasan Provincial Park (YPP, Gyeongsangnam Province, South Korea). We found strong spatial aggregation in each population and spatial independence in the interspecific spatial distribution, differing from previous studies. We further hypothesize that Cephalanthera species in sympatry within YPP are distributed somewhat randomly in space, perhaps due to the sharing of similar mycorrhizal fungi.