• Journal of Korean Ophthalmic Optics Society
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• v.9 no.2
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• pp.417-421
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• 2004

We can see that two images of reflection are observed on the surface of a ophthalmic lens. These are the image reflected from front surface and back surface of lens, respectively. The reflective image shows to be affect by surface refractive power of front and back surface of lens. Total refractive power of lens is calculated by refractive power of front and back surface of lens. Accordingly, the ratio of image on the lens surface is able to measure refractive power of ophthalmic lens without helping of the lensmeter. The ratio of two reflective image measured on the lens surface is compared with the calculated ratio by the power measurement.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.4 s.95
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• pp.366-372
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• 2005

This paper presents analysis of a slot array antenna having a low side lobe level and high front-to-back ratio for a repeater system of a satellite DMB(Digital Multimedia Broadcasting) service. Antennas for this repeater system require a high gain and enough isolation to reduce interferences between signals in system. Therefore, it is necessary to suppress a side lobe level and to increase front-to-back ratio. Unlike a structure 134 by lossy microstrip lines, in this work a single cavity-backed slot antenna array using a single waveguide feed is proposed to obtain the reliability for high power handling and high radiation efficiency. The side lobe level and front-to-back ratio are enhanced with tapered array technique and an optimized vertical reflector. The measured side lobe levels in H- and E-plane are under $-33.24\;\cal{dB}$ and $-35.78\;\cal{dB}$, respectively. The front-to-back ratio over $37.84\;\cal{dB}$, and the peak gain of over $17\;\cal{dBi}$ are measured.

• Journal of the Korean Home Economics Association
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• v.32 no.2
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• pp.219-230
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• 1994

The purpose of this comparative research is to investigate the change of the drafting method of the basic patterns for women in Korea. Followings were the findings of this research: 1) The concept of the basic pattern could be found after the first of the 1950s and there was introduction of the many basic patterns. At first measurement couldn't be found. Gradually the personal body type could be expressed in the basic pattern through the practical measurements such as the width of highest bust level and the length of neck to bust. 2) Through the ages the changes of the basic patterns were between 1950,60s and 1980,90s distinctively at the back width back shoulder angle front and back shoulder height from biceps line back neck ratio(height/width) BP position at the biceps line the amounts of underarm dart underarm dart position from the biceps lines and front ease angle at BP line. 3) 4 Grouping the types of the basic pattern followings are their characters; 1st Munwha or Doreme style 2nd waist dart group 3rd underarm dart and rectangular front ease 4th the usage of many measurements like as front length upper bust girth etc.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11b
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• pp.849-854
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• 2001

A study on performance of the sound absorbing noise barrier is presented. Noise barrier of sound absorbing type is composed of the front panel, sound absorbing material, and back panel. For allowing sound path, front panel is usually perforated. The performance of the noise barrier is governed by the opening ratio of the perforated panel, sound absorption coefficient of the sound absorbing material. In this study, the effects of the opening ratio, diameter of the hole, thickness of the sound absorbing material are investigated. It is found that the thickness of the sound absorbing material must be at least 50 mm to ensure the required minimum NRC value 0.70, and the opening ratio is greater than 0.2. It is shown that the thickness of the back panel is crucial in providing required STL (Sound Transmission Loss) value. The performance of the developed noise barrier is measured, where its sound absorbing coefficient and sound transmission loss satisfy the criteria.

• Journal of Broadcast Engineering
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• v.11 no.4 s.33
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• pp.448-457
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• 2006

HRTF DB, including the information of the sounds which is arrived to our ears, is generally used to make a 3D sound. But it can decline some three-dimensional effects by the confusion between front and back directions due to the non-individual HRTF depending on each listener. In this paper, we propose a new method to use psychoacoustic theory that reduces the confusion of sound image localization. And we make use of an excitation energy by the sense of hearing. This method is brought HRTF spectrum characteristics into relief to draw out the energy ratio about the bark band. Informal listening tests show that the proposed method improves the front-back sound localization characteristics much better than the conventional methods.

• Journal of radiological science and technology
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• v.2 no.1
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• pp.95-99
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• 1979

When the ${\gamma}-ray$ of average energy 375KeV emitted by Ir-192 is exposed to each film through lead foil with various thickness, the film sensitivity will be different according to the thickness of lead foil and film type. The results on the study, different density and sensitive ratio appeared depending on exposed time and film type, but was made on the following common points. 1. The effect of film sensitivity by the front lead foil showed rapid increase up to the thickness of more or less 0.03mm, and the thicker lead foil was decreased more in the thickness of about $0.05{\sim}0.09mm$. 2. The effect of film sensitivity by the back lead foil was increased up to around of $0.03{\sim}0.08mm$ thickness, the maximum sensitivity was obtained in the thickness of more than $0.03{\sim}0.08mm$ without any change in the above effect. 3. The sensitivity of front lead foil was higher than that of back lead foil in thin lead foil with about 0.127mm thickness, but the sensitivity of back lead foil was higher than that of front lead foil when thickness became thicker.

• Journal of the Korean Society of Clothing and Textiles
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• v.23 no.3
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• pp.353-360
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• 1999

An investigation made of the variations of angle of bias on the top of the sleeve cap curve line and calculated easing contraction ratio by capheights(A ; a,h$\times$5,/6) B: A, H/4 +4cm C:A.H/3 D: A.H/ 4+3cm E:AH/4+2cm, F: A,H/4+1cm, G: A,H/4, H:A,H/6, I:A,H/8) and the efects of easing contraction on the cap curve lines of sleeve A, D, G by easing stitch density with the gathering foot: sewing condition-lockstitch industrial machine stitch density(N1.0 ; 38stitches/3cm N1.5: 26stitches/3cm, N2.0 ; 19stitches/3cm, N2.5 ; 14stitches/ 3cm) The results obtained were as follows; 1) The variations of the angle of bias on the top of the sleeve cap curve line by cap heights can be done according to the angle balance (front; $\alpha$-$\beta$ back ; $\alpha$'- $\beta$') between the angle (front ;$\alpha$, $\beta$, back ; $\alpha$'- $\beta$') of bias of the two base-lines. 2) The higher cap height the more higher the calculated easing contraction ratio. 3) The lower the stitch density the higher easing contraction ratio. 4) The effects of easing contraction was that sleeve G was more than sleeve A, D.

• The Korean Journal of Community Living Science
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• v.24 no.4
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• pp.457-469
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• 2013

The purpose of this study is to quantitatively analyze the impacts of the distribution of easing contraction of the sleeve on the external appearance of bodice and sleeve through virtual clothing simulation. Virtual clothing is conducted by differentiating the sleeve easing in accordance with the experimental condition of bodice and sleeve that are followed by draping. And then the evaluation is carried out. As a result of an analysis of the similarity between the virtual garment and the actual clothing, the whole external appearance of the bodice and sleeve was expressed similarly. The external appearance according to the distribution of easing contraction got better as the easing contraction of sleeve was concentrated on sleeve cap in front while the appearance was better at the back as it was more gently distributed than in the front. In a comparison of armhole form, the clothing of which the top of it was most similar to S0 was S4 in which the gap between the armhole and the arm was the least and the front and rear silhouette fell relatively well. In a comparison between the position of bust circumference line and that of the sleeve base line, the front of the sleeve matched the bust circumference line as the easing contraction was distributed close to the center of the sleeve cap while in the back, the sleeve base line and the bust circumference line matched when some easing contraction ratio was added close to the armpit point. The cross section figures of garment space of the shoulder, the margin was evenly distributed in S4 or S5 with differing distributions of easing contraction in the front and the back. This study is significant in that it supplies the objective baseline data which makes a novice more able to make a good external appearance of the sleeve.

• Proceedings of the IEEK Conference
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• 2007.07a
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• pp.415-416
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• 2007

HRTF DB, including the information of the sounds which is arrived to our ears, is generally used to make a 3D sound. But it can decline some three-dimensional effects by the confusion between front and back directions due to the non-individual HRTF depending on each listener. In this paper, we propose a new method to use psychoacoustic theory that reduces the confusion of sound image localization. And we make use of an excitation energy by the sense of hearing. This method is brought HRTF spectrum characteristics into relief to draw out the energy ratio about the bark band and control low frequency band. Informal listening tests show that the proposed method improves the front-back sound localization characteristics much better than the conventional methods.

• Journal of the Korean Society of Clothing and Textiles
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• v.34 no.11
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• pp.1779-1785
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• 2010

The experiment is designed to create some useful data on the dressed shapes that contribute to simulating the adaptability of clothes. We studied the dressed shapes of blouse with above-elbow sleeves and sleeveless according to five types of arm movement (basic posture, reach forward 45, 90, and reach lateral 45, 90) in the stand-posture. Experiments were conducted to understand the dressed shape through 3-D measurement Vivid 910 and to investigate the width, depth, area distribution and gap of the shape of blouses on the section map with a software program for 3-D shape analysis, Rapid Form 2004. The Data were analyzed by factor analysis. The results of this study are as follows: The ratio of depth per width in the stand-posture was lower than other arm movements and the reach lateral was higher than the reach forward. The gap of the upper body was a briefed 4 factor; front, front-side, back, and back-side. It was higher than the sleeveless with a change of the gap in the dressed blouse with above-elbow sleeves by arm movements per stand-posture. The divisional gap shows the adaptability of clothes according to the types of blouse and arm movements in the change of the ratio.