• Title/Summary/Keyword: the center of a figure

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Various Uses of Center of Gravity-Awareness Comparison as the Center of a Figure (무게중심의 다양한 활용-시각적 인식을 통해 도형의 중심으로 활용)

  • Park, Yeong yong;Seol, Jin hwan
    • Journal for History of Mathematics
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    • v.34 no.4
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    • pp.137-149
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    • 2021
  • The center of gravity of a triangle is the center of a physical shape. This is the content in the second grade of middle school, 'The Use of Similarity'. Unlike the cases of circumcenter and incenter, which are easily recognized visually, it is not easy for teachers to guide students with the visual meaning of center of gravity. According to the survey results, students, regardless of academic achievement, grade, and major, perceived the center of gravity of various plane figure as the center of their shape within a limited area through visual judgment. With reference to the results and contents of this process, it is hoped that the point of the three medians is meaningful not only in argumentative definition that the intersection of the triple line is the center of gravity of the triangle, but also in the center of a figure.

Millimeter Wave MMIC Low Noise Amplifiers Using a 0.15 ${\mu}m$ Commercial pHEMT Process

  • Jang, Byung-Jun;Yom, In-Bok;Lee, Seong-Pal
    • ETRI Journal
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    • v.24 no.3
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    • pp.190-196
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    • 2002
  • This paper presents millimeter wave monolithic microwave integrated circuit (MMIC) low noise amplifiers using a $0.15{\mu}m$ commercial pHEMT process. After carefully investigating design considerations for millimeter-wave applications, with emphasis on the active device model and electomagnetic (EM) simulation, we designed two single-ended low noise amplifiers, one for Q-band and one for V-band. The Q-band two stage amplifier showed an average noise figure of 2.2 dB with an 18.3 dB average gain at 44 GHz. The V-band two stage amplifier showed an average noise figure of 2.9 dB with a 14.7 dB average gain at 65 GHz. Our design technique and model demonstrates good agreement between measured and predicted results. Compared with the published data, this work also presents state-of-the-art performance in terms of the gain and noise figure.

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Cascode Low Noise Amplifiers with Coplanar Waveguide Structure for Wireless LAN Application

  • Kim, Jong-Ho;Kim, Ki-Byoung;Lee, Jong-Chul;Kim, Jong-Heon;Lee, Byungje;Kim, Nam-Young
    • Journal of electromagnetic engineering and science
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    • v.3 no.1
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    • pp.12-16
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    • 2003
  • In this paper, low noise amplifiers with coplanar waveguide structure are presented for Wireless LAN data communication application. For comparison of microwave performance, LNAs of cascode type and balanced type using cascode cell with the same substrate and same bias conditions are designed and implemented. A cascode type of LNA shows the gain of 12.45 ㏈, input return loss of 11.63 ㏈, and noise figure of 1.52㏈. A balanced type of LNA using cascode cell shows the gain of 6.58 ㏈, input return loss of 16.6 ㏈, and noise figure of 1.18 ㏈.

A Basic Study on the Construction of Bodice Pattern for Development Figure of Trunk Surface (상반신 체표면전개도에 의한 길원형 설계의 기초 연구)

  • 문명옥
    • Journal of the Korean Society of Costume
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    • v.45
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    • pp.17-28
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    • 1999
  • This study was to analyze factors of the body form and factors of bodice pattern through a surface developement figure for the tight bodice pattern design. Fifty replicas of the trunk surface were made by applying a surgical tape method of female subjects between 18 and 24 years old. The result was as follows: 1. The gaps between direct measurements and measurements of the surface development figure were regarded as allowances for the tight bodice pattern. 2. There are four factors of body form selected by factor analysis. The 1st factor signifies th degree of fatness in the upper body. The 2nd factor signifies the length of the upper body. The 3rd factor signifies the part of the front shoulder. The 4th factor signifies the part of the neck. 3. There are high correlations between center back line of the surface development figure and back length line side line front length line back neck depth back upper chest depth. There are high correlations between back bust line of the surface development figure and back interscye breadth line back upper chest line back armhole line. There are high correlations between front bust line of the surface development figure and front upper chest line front interscye breadth line front armhole line front neck breadth 4. The regression expressions of measurements of the surface development figure of the upper body were analyzed as(Fig. 3).

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The Analysis of Children's Reasoning Types In Identifying Examples and Non-examples of a Triangle (삼각형인 예와 삼각형이 아닌 예의 식별 과정에서 나타난 초등학생의 추론 유형 분석)

  • Kim, Kyung-Mi;Kim, Hyun-Eun
    • Journal of the Korean School Mathematics Society
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    • v.13 no.2
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    • pp.263-287
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    • 2010
  • The purposes of the study were to investigate how children define a triangle, their reasoning types in identifying examples and non-examples of a triangle, and the relationship between their reasoning types and geometrical levels. Twenty-nine students consisted of 3th to 6th grades were involved in the study. Using the van Hiele levels of geometrical thought, children's reasoning types for identifying a figure as a triangle or non-triangle were categorized into visual reasoning, reasoning based on the figure's attributes and formal reasoning. The figure's attributes were further divided into critical and non-critical attributes. Most children identified a figure as a triangle or non-triangle based on critical attributes of the figure(e.g. closed figure, three, vertices, straight sides etc.) Some children identified a figure based on non-critical attributes of the figure(e.g. the length of the sides, the measurement of the angles, or the orientation of the figure). Particularly, some children who had lower levels of geometry identified a figure using visual reasoning, taking in the whole shape without considering that the shape is made up of separate components.

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Play Theory Comparative study with Amusement of Figure based on Image Contents and Roger Caillois (영상콘텐츠 기반 피규어의 유희성과 로제카이와의 놀이이론 비교)

  • Sohn, Jong-Nam;Chung, Jean-Hun
    • The Journal of the Korea Contents Association
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    • v.10 no.4
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    • pp.157-164
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    • 2010
  • Figure that make image contents of movie, animation, game etc. by base is one of representative industry of OSMU (One Source Multi Use). Figure that is culturally continuous as industrial while is growing scientific study that is lacking in many way consider. With amusement to the center as a preceding study about this and offered preceding research about theories that several scholars advocate, and divide into commerce, industry, imagination and amusement about characteristics of figure based on image contents and investigated. Investigated amusement characteristics of figure that is center of this study because do comparative analysis with insistence of Roger Caillois- Agon, Alea, Mimicry, Ilinks that classify to meaning that is four amusement characteristics competitions, fortune, conspiracy, dizziness - that is representative scholar of play theory and France's thinker. According to this study, we can know that there is close connection with amusement characteristics of four plays that Roger Caillois advocates in amusements of figure.

Enhancement of Magneto-Optic Figure of Merit of Bi:YIG Films in Blue Wavelengths by La Substitution

  • Lee, Euibok;Jaekyong Cho
    • Journal of Magnetics
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    • v.2 no.2
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    • pp.46-49
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    • 1997
  • This paper reports the first success in enhancement of the magneto-optic figure of merit of garnet films in blue wavelengths. The maximum of the absolute value of the Faraday rotation angle observed at about 500 nm for the films with no La substitution shifted toward shorter wavelength as La content increased, that leads the increase of the absolute value of the Faraday rotation angle in the wavelengths shorter than about 480 nm. The optical absorption coefficient at the wavelengths shorter than 500 nm decreased as La content increased. As a result the magneto-optic figure of merit increased in the wavelengths shorter than 470 nm as La content increased and was about two times larger for the film with La content of 0.6 in formular unit compared to that of the film without La substitution. This might be attributed to the shift of the centers of the charge transfer and crystal field transitions by La substitution.

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An Analysis of Somatotype of Elderly Women with Implications for Clothing Construction (노년층여성의 의복구성을 위한 체형분석 연구)

  • 김혜경
    • Journal of the Korean Home Economics Association
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    • v.20 no.4
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    • pp.53-67
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    • 1982
  • Physical measurements of 181 Korean elderly women, aged 60 through 79, living in the Seoul area, were taken in 1981 in order to analyze their body types and to study clothing construction according to their body types. The study was composed of 117 items in all; 35 items in measurements, 1 items in Rohrer index, 68 items in physical index to stature and bust girth, and 14 items in proportion, Coefficients of correlation among body dimensions were used. The results from this analysis are as follows: 1) The most significant changes in body dimensions in advanced age were the decrease of bust height and the increase of both abdomen girth and waist girth. 2) Distinct physical changes did not appear until advanced senescence(70~79 years of age). 3) In the three somatotype groups(thin, average, and plump) categorized by their Rohrer index, the dimensions that remained unchanged in senescence were back waist length and front waist length ; the dimensions that varied most significantly in senescence were the waist measurements. 4) As a result of the analysis of coefficients of correlation among the body dimensions of the 3 figure groups categorized by the Rohrer index, the fundamental dimensions for establishing the size of ready-to-wear garments of elderly women were the stature, bust girth and center back length in upper garments. 5) The result of the analysis of physical index and proportion of the 3 figure groups showed that the more plump a figure might be, the ratio of depth to width measurements increased; the back waist height was higher and trunk enlarged. 6) The 9 figure categorized by their Rohrer index and stature showed that the percentage of women in the category of“normal figure”decreased more in advanced senescence than during early senescence. 7) An analysis of variation of the 9 figure groups, the stature and other items for a short and thin figure were the smallest, and for a tall and plump figure, the largest.

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A Classification of Obese Middle-aged Men's Lower Body Shapes (비만 중년 남성의 하반신 체형 분류에 관한 연구)

  • Lee, Bo-Na;Suh, Mi-A
    • The Research Journal of the Costume Culture
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    • v.19 no.6
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    • pp.1150-1162
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    • 2011
  • Considering the fact that the fit for men's clothes is important for the sizing system modern ready-made pants, an analysis of obese middle-aged men is required at this period of time to determine the appropriate fit for obese men. The following research focused on 635 middle-aged obese men who had a BMI index of at least 25 and a waist circumference from the belly-button level of 34 inches or more. This research deals with the articles of circumference, thickness and other major physical changes that happen during the 30s, 40s, and 50s. According to the analysis of these body measurement articles with specific regard to age, men's height and the height of their waist seemed to decrease as their age increased. This demonstrates that as these men grow older, the waist and stomach slowly curved into a circular and flat body type due to their obesity. In this study, the first factor figure was the height and leg length. The second factor figure was the waist form. The third factor figure was the center thigh circumference. The fourth and fifth factor figures were the hip length and shape. Lastly, the sixth factor figure was the calf circumference. These 6 factor figures construct 80.57% of the volume explanation and showed 3 patterns through a cluster analysis that showed different patterns of obesity forms for waist circumferences in key figure 1, waist and thigh circumferences in key figure 2, and waist and buttocks circumferences. Therefore, it was worthwhile to consider the circumferences of the waist, buttocks and thigh according to the body type category to enhance the drafting of well-fitting pants.

A Study of figure's episodes of in a Collection of Lee, Duck Moo's Works(ChungJangKwan Junseo) (이덕무(李德懋) 『청장관전서(靑莊館全書)』 소재 인물 일화(逸話) 연구)

  • Kim, Kyun-tae
    • Journal of Korean Classical Literature and Education
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    • no.15
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    • pp.389-419
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    • 2008
  • I already wrote a thesis about A Study of Ideologies and Stylistic Features of the Oral Narratives in a Collection of Lee, Duck Moo's Works(ChungJangKwanJunseo)" in The Classical Literature and Education Vol.11, (2006). At that time I held over a study of figure's episodes. So this essay is a series of the thesis. In this essay, I described his critical ideas about the figure's episodes of other people. I classified as the gentry's episodes and the common's episodes, and ones more classified these as the Confucian's moral episodes and the oddity's strange episodes. And I studied the narrative principles and features of narrative structure. He asked for a reasonal thinking attitude in the figure's episodes of other people. In his the gentry's episodes he indicated as a important value the constant attitude of propriety and dignity. The other hand, in his the common's episodes he thought importantly a practical act of the Confucian's moral. He showed man's equality and criticized the anti-practical attitude of the gentry group. In the oddity's strange episodes were focused on the super ability of figures in the both of groups. And then even though there are unreal or unreasonable contents in the oddity's strange episodes, he did not criticize. His such attitude was came out to take interest in unreal story like the Paesasopeum(稗史小品). The the narrative principles of his episodes are two types, one is a summary or a report type, the other is a descriptive of events type. the former was explained by narrater, the latter was described as the indirect or direct narration of the characters. In the structure of narrative in case a summary type were enumerated with the episodes, but in case a report or descriptive type of events were contrasted with characters. A story-telling way of figure's episodes borrowed from 'Jeon(傳)' or 'Yadam(野談)' genre. And a point of view in case a summary or a report type was consisted with a center of narrater, in case a descriptive of events type was consisted with a center of witness.