• Title/Summary/Keyword: four classes

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Evo-Devo of Leaf Shape Control with a Special Emphasis on Unifacial Leaves in Monocots

  • Yamaguchi, Takahiro;Tsukaya, Hirokazu
    • Korean Journal of Plant Taxonomy
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    • v.37 no.4
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    • pp.351-361
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    • 2007
  • In angiosperms, leaves typically develop as three-dimensional structure with dorsoventral, longitudinal, and lateral axes. We have shown that the control of two axes of leaves, longitudinal and lateral axis, can be genetically separable, and four classes of genes are responsible for the polar cell expansion and polar cell proliferation in Arabidopsis. In monocots, unifacial leaf, in which leaf surface consists only of abaxial identity, has been evolved in a number of divergent species. The unifacial leaves provide very unique opportunities for the developmental studies of the leaf axes formation in monocots, because their leaf polarities are highly disorganized. In addition, the mechanism of the parallel evolution of such drastic changes in leaf polarities is of interest from an evolutionary viewpoint. In this article, we describe our recent approaches to reveal the mechanism of unifacial leaf development and evolution, including recent advances in the leaf polarity specification in angiosperms.

New records of terrestrial and freshwater ciliates (Protozoa: Ciliophora) from Korea: Brief descriptions with notes

  • Moon, Ji Hye;Park, Mi-Hyun;Jung, Jae-Ho
    • Journal of Species Research
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    • v.6 no.spc
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    • pp.1-7
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    • 2017
  • Eight samples, collected from six moss-covered soil and two freshwater samples, were examined to determine ciliate diversity in Korea. Based on the morphology of living and stained specimens, thirteen ciliate species, previously unrecorded in Korea, were identified. These specimens were classified to four classes, seven orders, ten families, and twelve genera. Of these genera, the following six were first records in Korea: Bresslauides, Dexiotricha, Glaucoma, Paragastrostyla, Sathrophilus, and Trithigmostoma. Here, we provide a brief description of the morphology of these 13 taxa along with microphotographs and notes.

Korean EFL Learners' Listening Anxiety, Listening Strategy Use, and Listening Proficiency

  • Kim, Ji-Sun
    • English Language & Literature Teaching
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    • v.17 no.1
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    • pp.101-124
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    • 2011
  • This paper investigated the relationships among Korean EFL learners' listening anxiety, listening strategy use, and listening proficiency. One hundred and forty four Korean college students who were enrolled in the required practical English classes participated in this study. Questionnaires related to students' listening strategy use and listening anxiety were administered and a TOEIC listening comprehension test was given to measure the students' listening proficiency. The one-way ANOVA was used to analyze the data. The findings of this study are that the students' listening performance is positively correlated with their strategy use and negatively correlated with their anxiety level, and their strategy use is negatively correlated with their anxiety level. The results suggest that successful learning will occur when anxiety is reduced and when the use of strategies is encouraged more often. The pedagogical implications for EFL educators and teachers are described.

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A classification techiniques of J-lead solder joint using neural network (신경 회로망을 이용한 J-리드 납땜 상태 분류)

  • Yu, Chang-Mok;Lee, Joong-Ho;Cha, Young-Yeup
    • Journal of Institute of Control, Robotics and Systems
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    • v.5 no.8
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    • pp.995-1000
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    • 1999
  • This paper presents a optic system and a visual inspection algorithm looking for solder joint defects of J-lead chip which are more integrate and smaller than ones with Gull-wing on PCBs(Printed Circuit Boards). The visual inspection system is composed of three sections : host PC, imaging and driving parts. The host PC part controls the inspection devices and executes the inspection algorithm. The imaging part acquires and processes image data. And the driving part controls XY-table for automatic inspection. In this paper, the most important five features are extracted from input images to categorize four classes of solder joint defects in the case of J-lead chip and utilized to a back-propagation network for classification. Consequently, good accuracy of classification performance and effectiveness of chosen five features are examined by experiment using proposed inspection algorithm.

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A Study on the Development of a Scale Measuring Life Satisfaction of After-School Child Care (아동의 방과후 보육 생활 만족도 척도 개발 연구)

  • Shin, Hye-Kyong;Suh, Young-Sook
    • Korean Journal of Child Studies
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    • v.31 no.1
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    • pp.101-111
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    • 2010
  • The purpose of this study was to develop a scale to measure the life satisfaction of after-school classes. For this purpose, utilizing the theoretical background and the findings of previous studies, 147 questions from eight factors were selected for the 1st draft and 67 questions were selected for the 2nd draft by reviewing the validity of the contents after consulting with eleven professionals. A preparatory survey and factor analysis was then conducted using 291 people and a total of 32 questions were extracted from four sub-factors. Exploratory factor analysis by principal component analysis was conducted and orthogonal rotation was conducted by means of the VARIMAX method. The reliability of the class environment, operation management, program and teacher relationship sector were found to be very high. It is suggested that this study can be of great benefit in developing a child-centered scale and it's reliability was also found to be high.

A Study on the Presentation of Idea in Information and Entropy Theory in Vegetation Data (식피 Data 에 대한 Information 과 Entropy 이론의 실용연구)

  • Park, Seung Tai
    • The Korean Journal of Ecology
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    • v.10 no.2
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    • pp.91-107
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    • 1987
  • This study is concerned with some methods and applications, used as a basis on information and entropy analysis of vegetation data. These methods are adopted for the evaluating the effect of sampling intensity on information, which repersnets the departure of observed variable from standard component. Classes on the data matrix are caluculated by using marginal dispersion array for rank and weighting information program. Finally the information and entropy are computed by applying seven options. On the application of vegetation studies, two models for cluster analysis and analysis of concentration are explained in detail. Cluster analysis is based on use of equivocation information and Rajski's metrics. The analysis of concentration utilizes coherence coefficience being transformed values, which has been adjusted from blocks and entropy values. The relationship btween three begetation clusters and four stands of Naejangsan data is highly significant in 79% of total variance. Cluster A relatively tends to prefer north side, and cluster C south side.

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Virtual World On-line Lecture System based on Mixed Reality (혼합현실 기반의 가상 세계 온라인 강의 시스템)

  • Kwon, Oh-Young;Seo, Hyo-Seok;Teles, Gustavo
    • The Journal of Korean Institute for Practical Engineering Education
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    • v.3 no.1
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    • pp.97-102
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    • 2011
  • Learning system on virtual environment gives the immersive feeling that lacks in existing E-Learning system, excites user's interest, and offers dangerous and expensive education contents. In this paper, we classified the learning categories into four classes: realtime lecture, anytime study, practice education, and the activity of study group. We built the on-line lecture system using Second Life that supports 3D virtual world and mixed reality. We provided virtual learning environment as running developed virtual world on-line lecture system.

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Flood Search Algorithm with MFDL Path in Circuit-Switched Networks (회선 교환망에서 MFDL 경로를 이용한 Flood Search 알고리즘)

  • 박영철;이상철;은종관
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.18 no.3
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    • pp.360-371
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    • 1993
  • Flood search algorithm is known to be an effective routing mechanism for tactical application, since it provides high degree of survivability and robustness. But it is known that it has significant drawbacks with respect to the network efficiency [1]. We consider a tactical circuit-switched grid network with a maximum of four links and two priority classes of voice traffic, Using the minimum first-derivative length (MFDL) path, we improve the blocking probability performance of the circuit-switched network without increasing the call set-up time and processor loading of the algorithm.

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a study on the Electrical and acoustical properties of PZT ceramic. (PZT 계 압전세라믹스의 전기 및 음향특성에 관한 연구)

  • Kim, S.J.;Kim, H.G.;Lee, D.C.
    • Proceedings of the KIEE Conference
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    • 1989.07a
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    • pp.333-334
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    • 1989
  • Electrically active part of the piezoelectric sound element is a ceramic thin circular disk cemented to a metal base plate (using a type of thermosetting epoxy). The active part is a thin lead zirconate titanate disk (PZT). The piezoelectric sound element is so dimensioned that its basic resonance frequency is approximately if the center of the audible frequency band: This frequency is mainly determined by the geometry and the sort of the metal base plate materials. In this study, four kinds of PZT ceramic and two classes of thin metal base plate were prepared. It is observed that dielectric and pizoelectric properties relate to acoustical properties (particularly sound pressure level).

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Enabled the research in mission of youth culture as a musical worship (뮤지컬 예배로서 청소년 문화선교 활성화 연구)

  • Lee, Jang-Weon
    • Journal of The Korean Digital Architecture Interior Association
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    • v.11 no.4
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    • pp.81-86
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    • 2011
  • Activation of Youth Culture Mission For Activation of Youth Culture Mission Is classified into four classes. The concept of youth and youth culture, Cultural tools, Feasibility and effectiveness of open worship, Practical effect of this practice, It Said method. One of those ways will have an interest in musical as a young missionary tool. Young people might like that have been pomp and popularity, and the diversity of characterized. Utilized as a musical worship need to know what will be it. Current musical worship will be of interest which the potential. Them will be able to achieve what you want in terms of open worship it solve the problem. Entirely worship for youth Is come up their gaze and posture. that In terms of you have it musical worship is called public and intimacy. Difficulties with religion think it come up with tools that musical.