• 제목/요약/키워드: formation period

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변인 통제 논리와 상관 논리 미형성 학생의 논리 학습을 위한 최적 시기 연구 (A Study of Optimal Periods for Learning Non-formation Students in Variable Controlling and Correlational Reasoning)

  • 김영신;박현철
    • 한국초등과학교육학회지:초등과학교육
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    • 제28권2호
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    • pp.154-160
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    • 2009
  • Correlational reasoning is used to analyze results from an experiment and create meaningful relationships among variables. Although there were many recognition development studies, not a single study found the optimal period for the development of logical thinking. Therefore, the purpose of this study is to find the optimal period for students whose logic for variable controlling and correlational reasoning are poor. This study made a logic program treatment subject for students between the 4th and 8th grade whose recognition in reasoning has not been developed in general in order to find the optimal period for their development. The variable-controlling reasoning was performed the program of voice survey and sugared-water melting in subsection survey and sugared-water melting in subsection. And, the correlation reasoning was performed the program of rat's size and tail color, treatment, and effect. As a result of research, students, who were not formed variable controlling and correlational reasoning, could be known to be enhanced through learning, but to fail to be formed the qualitative change like the cognitive development. In other words, the optimal period couldn't be found that is grown the formation of students, who are not formed the variable controlling and correlational reasoning, through learning. It is expected that this research can contribute to the improvement of students' cognitive level and there would be more active researches in different fields to improve the cognitive level.

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Mathematical Models for the Biofilm Formation of Geobacillus and Anoxybacillus on Stainless Steel Surface in Whole Milk

  • Karaca, Basar;Buzrul, Sencer;Cihan, Arzu Coleri
    • 한국축산식품학회지
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    • 제41권2호
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    • pp.288-299
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    • 2021
  • Biofilm formation of Geobacillus thermodenitrificans, Geobacillus thermoglucosidans and Anoxybacillus flavithermus in milk on stainless steel were monitored at 55℃, 60℃, and 65℃ for various incubation times. Although species of Geobacillus showed a rapid response and produced biofilm within 4 h on stainless steel, a delay (lag time) was observed for Anoxybacillus. A hyperbolic equation and a hyperbolic equation with lag could be used to describe the biofilm formation of Geobacillus and Anoxybacillus, respectively. The highest biofilm formation amount was obtained at 60℃ for both Geobacillus and Anoxybacillus. However, the biofilm formation rates indicated that the lowest rates of formation were obtained at 60℃ for Geobacillus. Moreover, biofilm formation rates of G. thermodenitrificans (1.2-1.6 Log10CFU/mL∙h) were higher than G. thermoglucosidans (0.4-0.7 Log10CFU/mL∙h). Although A. flavithermus had the highest formation rate values (2.7-3.6 Log10CFU/mL∙h), this was attained after the lag period (4 or 5 h). This study revealed that modeling could be used to describe the biofilm formation of thermophilic bacilli in milk.

생활체육 참여가 사회자본 형성에 주는 영향의 실증적 분석 (Effects of Participation in Sports for All on the Formation of Social Capital)

  • 김재경;박득희;;정순옥
    • 지식경영연구
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    • 제13권4호
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    • pp.1-12
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    • 2012
  • This study is to analyze the effect of participation in sports for all on the formation of social capital. For this purpose, this study used convenience sampling method with the 150 subjects who participated Sports for All in Seoul and Gyeonggi area. and selected 150 questionnaires excluding 30 unsuitable for the data. For data analysis was made by SPSS 17.0, performing exploratory factor analysis, reliability analysis, correlation analysis and multiple regression model. This analysis reveals that (1) participation eagerness in sports for all influence on influence on the formation of social capital.(social capital consist of information sharing, norms, trust, network) (2) participation period of time and participation frequency in sports for all don't influence on on the formation of social capital. (3) socioeconomic background don't influence on the formation of social capital. Therefore, it is necessary to improve the eagerness in sports for all.

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서산층군(瑞山層群)의 층서(層序) 및 변성작용(變成作用) (Stratigraphy and Metamorphism of Seosan Group)

  • 나기창;김형식;이상헌
    • 자원환경지질
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    • 제15권1호
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    • pp.33-39
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    • 1982
  • The Seosan Group in the Taean peninsular can be divided into Seosan formation and Daesan formation according to its metamorphism and stratigraphy. The Seosan formation is composed of iron bearing quartzite and schist which are strongly metamorphosed and migmatized about 2572 m.y.ago. The Daesan formation is composed mainly of quartzite and crystalline limestone. They were intruded by granite gneiss 2370m.y ago and metamorphosed two or three times before Jurassic Period. The Group is overlain by Taean formation which shows low grade metamorphism. Total three times metamorphic events can be recognized in these areas. First and second metamorphisms are predominent in amphibolite facies, the last metamolphism is mostly greenschist facies.

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Formation of Sensory Pigment Cells Requires Fibroblast Growth Factor Signaling during Ascidian Embryonic Development

  • Kim, Gil-Jung
    • Animal cells and systems
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    • 제7권3호
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    • pp.221-225
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    • 2003
  • The tadpole larva of the ascidian Halocynthia roretzi has two sensory pigment cells in its brain vesicle. To elucidate the temporal requirement for FGF signaling in formation of the pigment cells, embryos were treated with an FGF receptor 1 inhibitor, SU5402, or an MEK inhibitor, U0126 during various embryonic stages. In the present study, it is shown that the embryos treated with SU5402 from the 16-cell stage to the early gastrula stage do not form pigment cells, whereas those treated after the early gastrula stage form pigment cells. In pigment cell formation, embryos suddenly exhibited the sensitivity to SU5402 only for 1 h at the neural plate stage(-4 h after the beginning of gastrulation). When U0126 treatment was carried out at various stages between the 8-cell and late neurula stages, the embryos scarcely formed pigment cells. Pigment cell formation occurred when the embryos were placed in U0126 at early tail bud stage. These results indicate that FGF signaling is involved in pigment cell formation at two separate processes during ascidian embryogenesis, whereas more prolonged period is required for MEK signaling.

의복의 인상형성이론에 대한 연구동향 (A Tendency of Study on Theory of Impression Formation by Clothing)

  • 이경화;나수임
    • 복식문화연구
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    • 제7권1호
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    • pp.117-127
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    • 1999
  • Clothes are a kind of silent language that tells someone who has in wear and has great influence on person perception and impression formation. Present paper aims, therefore, to investigate the tendency of its study to offer information that my assist future studies. Doctorial dissertations, master\`s theses and journal articles related with clothing and textiles in domestic are categorized according to period and subject. Analysed results are as follows: First, as for the periodic vicissitude, the number of study on impression formation was before 1990, but tend to increase in 1990\`s. Second, as for the subject, while the studies focused on impression formation wearer on the first half of 1990\`s, they were segmented and presented wearer\`s form and appearance in detail ; computer simulation was also made use of in various papers. In conclusion, impression formation seems to become a rather important subject for further study.

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춘천지역에서 생장하는 주요 수종의 연륜형성(I) - 형성층 활동기간에 관하여 - (Annual Ring Formation of Major Wood Species Growing in Chuncheon, Korea(I) - The Period of Cambium Activity -)

  • 권성민;김남훈
    • Journal of the Korean Wood Science and Technology
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    • 제33권4호통권132호
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    • pp.1-8
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    • 2005
  • 춘천지역에서 생장하는 주요수종의 생장특성을 규명하기 위해 형성층 분열기 및 형성층의 휴지기를 조사하였다. 소나무와 잣나무는 3월 중순~하순에 형성층 활동이 시작되었다. 5월 하순에서 7월 중순 사이에 형성층 세포의 분열이 활발하였고, 이 때 잣나무의 세포 수가 소나무의 세포 수보다 크게 증가하였다. 환공재인 신갈나무와 아까시나무의 형성층 분열은 3월 중순경에 개시되었으며 동시에 도관 형성이 시작되었다. 산공재인 층층나무와 산벚나무의 형성층은 4월 초에 분열을 개시하였고 도관은 이보다 1~3주일 늦게 형성되는 것으로 관찰되었다. 형성층 활동이 멈추는 시기는 침엽수 11월 초순경, 활엽수 10월 중순경으로 관찰되었다. 따라서 형성층의 활동은 동일한 환경조건에서도 수종간에 차이가 있는 것으로 나타났다.

지방 항구도시의 토지이용 변화에 관한 연구 - 전라남도 여수시를 중심으로 - (A Study on Changes of Land Use in the Local Port City - Focused on Yeosu in Jeonnam Province -)

  • 정금호
    • 한국농촌건축학회논문집
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    • 제25권1호
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    • pp.9-16
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    • 2023
  • This study is on the formation and the development process of urban space by referring to the literature in Yeosu where is the important location in logistics & transportation and maritime since the Japanese colonial period. There are many factors and results of the development process in Yeosu by the opening port, railroads, loads and industries. The purpose of this study is to understand the characteristics of the formation process of urban space and the characteristics of physical space in Yeosu. The results are as follow; The urban formation and development process in Yeosu where was a small fishing village in the 1910s is largely divided into four processes. Formation: the population increased due to constructions such as of a railroad, a port, and roads and there were many reclamations around the center of the old city center in the Japanese colonial period. Stagnation: There was no urban development due to stagnation, war, and the Yeo-sun Incident. Expand: the industrialization of the Yeocheon Industrial Complex and Gwangyang Steel and other areas around Yeosu led to a surge in Yeosu's population. To cope with this, the city was expanded through three land readjustment projects and the development of large-scale residential complexes. Decline and Remodeling: Yeosu's urban space declined due to the decline of fisheries and the decrease in marine and railway logistics. And the expansion and improvement of the transportation network for hosting the Yeosu World Expo increased the accessibility of the old city center, transforming it into a tourist city using cultural heritage and nature.

남포층군의 아미산층에서 산출된 패갑류 화석 (Fossil Conchostraca from the Amisan Formation of the Nampo Group, Korea)

  • 김종헌;이귀형
    • 한국지구과학회지
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    • 제36권2호
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    • pp.181-189
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    • 2015
  • 충청남도 서부에 분포하는 아미산층에서 많은 패갑류 화석이 채집되었다. 이들 화석은 아미산층의 여러 층준에서 밀집된 상태로 산출되며, 아열대 기후의 담수 환경에서 번성한 것으로 추정된다. 아미산층산 패갑류 화석은 다음과 같이 3속 4종으로 분류되었다: Euestheria kawasakii, E. shimamurai, Sphaerestheria koreanica, 그리고 Cyclestherioides rampoensis. 그중에서 후자는 이전에 아미산층에서 기록된 종이고, 나머지 3종은 새로이 발견된 종이다. 패갑류 화석에 의한 아미산층의 지질 시대는 후기 트라이아스기로 추정된다.

Role of Mass Inflow and Supernova Feedback on Nuclear Ring Star Formation

  • Moon, Sanghyuk;Kim, Woong-Tae;Kim, Chang-Goo;Ostriker, Eve C.
    • 천문학회보
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    • 제46권2호
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    • pp.37.1-37.1
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    • 2021
  • Observations suggest the star formation in nuclear rings of barred galaxies proceeds episodically in time and sometimes asymmetrically in space. Existing theories and numerical simulations suggest that the episodic star formation is perhaps due to either supernova feedback combined with fluid instabilities or time-varying mass inflow rate. However, it has been challenging to discern what dominates in shaping the star formation history because the effects of the inflow and feedback are blended in global simulations of nuclear rings. To understand their effects separately, we construct semi-global models of nuclear rings, which treat the mass inflow rate as a model parameter. By running simulations with the inflow rates kept constant or oscillating in time, we find that the star formation rate (SFR) of the rings varies coherently with the inflow rate, while the feedback is responsible only for stochastic fluctuations of the SFR within a factor of two. The feedback instead plays an important role in maintaining the vertical dynamical equilibrium and setting the depletion time. While the asymmetry in the inflow does not necessarily lead to the asymmetry in the star formation, we find that the rings undergo a transient period of lopsided star formation when the inflow rate of only one dust lane is suddenly increased.

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