• Journal for History of Mathematics
• /
• v.34 no.4
• /
• pp.137-149
• /
• 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.

• Journal of electromagnetic engineering and science
• /
• v.3 no.1
• /
• pp.12-16
• /
• 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 ㏈.

• ETRI Journal
• /
• v.24 no.3
• /
• pp.190-196
• /
• 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.

• Journal of the Korean Society of Costume
• /
• v.45
• /
• pp.17-28
• /
• 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).

• The Journal of the Korea Contents Association
• /
• v.10 no.4
• /
• pp.157-164
• /
• 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.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 1997.03a
• /
• pp.117-120
• /
• 1997

Microstructure and pole figure through thickness in cold rolled sheet steel were investigated. The calculated plastic strain ratio in surface is greatly different with that in center layer and measured value in tensile test.

• Journal of Magnetics
• /
• v.2 no.2
• /
• pp.46-49
• /
• 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.

• Women's Health Nursing
• /
• v.25 no.2
• /
• pp.232-233
• /
• 2019

• Journal of the Korean School Mathematics Society
• /
• v.13 no.2
• /
• pp.263-287
• /
• 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.

• Journal of the Ergonomics Society of Korea
• /
• v.27 no.4
• /
• pp.1-8
• /
• 2008

Objective: This study is to analyze the factor affecting elderly's speed of mobile phone ability. Method: Sixty healthy senior citizens who live in Kim-hye participated in Cognition, Visual perception, Speed of mobile phone ability and the collected data was analyzed by an independent multiple regression analysis. Result: The findings can be summarized as follows; 1. Although men were faster than women while using mobile phone, there was little satisfical significance(p<0.05). 2. Although people in their sixties were faster than people in their seventies while using mobile phone, there was minial difference(p<0.05). 3. The primary factor which affect mobile phone using speed is figure ground, visual memory, visual processing and the most beneficial discovery in the entire project is figure ground(p<0.05). Conclusion: The result of study showed that in order to enhance figure ground, visual memory, visual processing in mobile phone using speed. These results will be consider useful for elderly's mobile phone ability.