• Journal of Korean Ophthalmic Optics Society
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• v.16 no.1
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• pp.97-106
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• 2011

Purpose: This review article was written to theoretically compare the depressing force (pressure, adhesion) to the cornea between when the spherical lenses were being tightly and flat fitted. Methods: Mathematical equations and their numerical solution programs (model) were formulated to calculate the depressing (adhesion) force to the cornea by both the tightly and flat fitted contact lenses. Based on this proposed model the effects of parameters characterizing a contact lens such as BCs, diameters, edge shape and corneal shape (ratio of long and short corneal axis, p) on the depressing force to the cornea were predicted/analyzed in both tightly and flat fitting regimes. Results: Corneal adhesion increased as the corneal p-value increased. Adhesion increase caused by the increased p-value was much larger in flat fitted case than in tight fitted one. Corneal adhesion reduced abruptly as the BC increased in flat fitting regimes while the adhesion rise was insignificant in tight fitting ones. Reduction in corneal adhesion due to lens-size increase was predicted to be insignificant in both tight and flat fitting regimes. Both the lens edge shape (edge angle) and thickness were relevant only in tight fitting regime. Corneal adhesion increased as the increased with tight-fitted lenses. As the thickness of tight fitted lenses increased, corneal adhesion inversely decreased. Conclusions: The two most significantly affecting the depressing force to cornea were found to be the degree of corneal bending toward the periphery and the BCs of lenses.

• Journal of Korean Clinical Health Science
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• v.4 no.4
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• pp.662-670
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• 2016

Purpose. Because of a recent increase in use of soft contact lens at younger ages, in the present study, the correlation between corneal eccentricity and radius of curvature and fitting types of contact lens was investigated. Methods. The study evaluated the fitting status of targets through lens centration, push-up test, dynamic lag test and static lag test of lenses usually worn by 49 men and women (98eyes) in their 20s to 30s who put on soft contact lenses. After evaluation, the subjects were classified into 3 categories by fitting status(steep, aligment and flat). The radius of corneal curvature in the naked eyes was measured by using keratometer. Moreover the corneal eccentricity in the nasal side, temporal side, superior side and inferior side was measured by using the device capable of measuring the corneal eccentricity. Results. The radius of corneal curvature and corneal eccentricity of soft lenses worn by subjects were higher in the order of steep fitting and flat fitting, and the higher average corneal curvature radius and corneal eccentricity is intend to be more steep fitting(p=0.051, p=0.052). The corneal eccentricity showed a tendency to nasal fitting type at the higher eccentricity and temporal fitting type at the smaller eccentricity, statistically significant difference was observed(p<0.05). The study showed there were low correlation that nasal and temporal side at steep fitting, superior side at normal fitting and 4side(nasal, temporal, superior, inferior) at flat fitting, therefore when the corneal eccentricity changed the radius of corneal curvature also changed. The corneal eccentricity and the radius of corneal curvature showed statistically significant difference at 4side and each fitting types(p<0.05). Conclusions. The results of this study, the fitting status, of wearer are based on radius of corneal curvature and corneal eccentricity, and if lens fitting would be done considering that, it seems to be useful in a soft contact lens prescription.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.2
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• pp.163-169
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• 2014

Purpose: This study is for compared the change of corneal refractive power before and after wearing of rigid gas permeable contact lense with diagnostic method which is 1 D flatter than alignment fitting on right eye and alignment fitting on left eye for 2 months and investigate the preference. Methods: Twenty middle school and high school students (40 eyes) who had never worn a contact lense before for no corneal topographical change, no ocular disease, no experience of ophthalmic surgery and have normal tear amount were selected for this study and corneal refractive power were examined before wearing rigid gas permeable contact lense and adaptation status and corneal examination were performed after 10 days of wearing and after cheking up the continuation of wearing, all candidate wear contact lens 8 hours per day for 2 month and corneal refractive power were compared. Results: After 2 months of wearing with 1 D flatter than the alignment fitting on right eyes, there was significant difference in the central corneal refractive power was $43.84{\pm}1.33D$, flat K power was $43.05{\pm}1.29D$, and steep K power was $44.61{\pm}1.42D$ decreased than before wearing (p<0.001, 0.001, 0.047). The e-value of the principal meridians also shows statistically significant difference (p=0.037, 0.015). After 2 months of wearing with alignment fitting on left eyes, the central corneal refractive power was $44.40{\pm}1.26D$, flat K power was $43.57{\pm}1.23D$. and flat K e-value was $0.58{\pm}0.05$ which showed no statistically significant difference (p = 0.769, 0.614, 0.181). But steep K power was $45.25{\pm}1.36$, and steep K e-value was $0.45{\pm}0.18$ which shows statistically significant difference (p=0.018, 0.027). Conclusions: Consider the comfort, clear vision, dryness for preference fitting investment, 6 students (30%) prefer right eye which is 1 D flatter fitting, 14 students (70%) prefer left eye which is alignment fitting. For rigid gas permeable fitting needed for accurate examination and should prescribe the alignment fitting which is suitable for each cornea.

• Journal of the Korean Society of Costume
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• v.59 no.1
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• pp.94-105
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• 2009

Jeogori, Korean jacket, can be categorized into two styles. Traditional style Jeogori is based on conventional construction method for ceremonial or festive occasions. Contemporary casual style Jeogori is based on western style flat pattern making for better fitting and functionality. Traditional style Jeogori is quite flat on human body because it is not considered the grade of shoulder line and is drawn by vertical & horizontal line. This characteristic feature causes weakness in functionality and comfort compared to contemporary casual style. Apparently contemporary casual style has better wearing comfort. Yet to most Koreans, contemporary style Jeogori seems to lack of some characteristic style of its own. This study is to find out how to make Jeogori well balanced in terms of functionality, fit, comfort and traditional style. Currently used Jeogori patterns are compared in order to select the best among them. Onto the selected pattern, several alterations were tried focused on shoulder, armhole and sleeve lines to make optimal modifications. After several comparative fitting tests, the final pattern making method was suggested.

• Journal of Korean Ophthalmic Optics Society
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• v.17 no.3
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• pp.255-264
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• 2012

Purpose: In this study, the effect of lens fitting status on the contact area between spherical/aspherical RGP lens and the cornea having different astigmatic degree and corneal type was investigated for guiding the proper selection of RGP lens. Methods: Spherical and aspherical RGP lenses were applied on ninety eyes $(25.12{\pm}3.52years)$ having with-the-rule astigmatism by different fitting status. Then, their central, mid-peripheral and peripheral areas of fluorescein pattern were calculated and compared for the quantitative evaluation of the contact area between spherical/aspherical RGP lens. Results: The central and peripheral areas with the alignment fitting was significant different based on lens design. However, the central area didn't show any significant difference by lens design and corneal type when fitted in steep or flat. When analyzed by the corneal shape, both lenses with alignment and flat fitting had significant difference in central and peripheral areas. However, the central, mid-peripheral and peripheral areas with steep fitting didn't show the difference by corneal types. When analyzed by the astigmatic degree, the central and peripheral areas with alignment fitting changed proportionally to the increase of corneal astigmatism regardless of corneal shape. With steep and flat fitting, however, the central, mid-peripheral and/or peripheral areas in round- and symmetric bowtie-typed corneas showed the conflicting result when compared to those of alignment fitting when analyzed by the astigmatic degree. Conclusions: In this study, it was confirmed that the contact areas of cornea and RGP lens fitted steep and flat status were largely affected by the corneal type and corneal astigmatism rather than RGP lens fitted in alignment status. Also, this result commonly occurred in both spherical and aspherical RGP lenses.

• Journal of the Korean Society of Clothing and Textiles
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• v.27 no.8
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• pp.946-957
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• 2003

This study aimed to suggest a simple and well-fitting flat pattern drafting method for a men's jacket. Four jackets in thick muslin were made from four different drafting methods utilizing a few measures as breast girth, center back length, and chest width, which were not much different from the drafting methods of woman's jacket. The appearance of the 4 jackets was evaluated by a pool of evaluators consisted of graduate students who had much clothing construction teaching experiences and their motion adaptability was evaluated by two wearers who belonged within the range of the average measures of the Korean male figure as reported from the 1997's Census for Standard Body Measure. A drafting method evaluated as the most well-fitting and well-functioning in general was chosen and modified to enhance the appearance and was reevaluated to confirm its fit improvement. As a result of this study, a new drafting method, simple and not much different from that of a woman's jacket pattern drafting method is proposed. Since this method is based on the minimal measures and ratios thereof, and is not as complicated as ordinary drafting methods for men's wear, the researcher expects that this drafting method allows more chances for the students to learn and understand men's wear more easily and comfortably.

• Journal of Institute of Control, Robotics and Systems
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• v.8 no.9
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• pp.812-817
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• 2002

This paper presents a development of high accuracy aligner and describes a method to find the orientation of a substantially circular disk shaped wafer with at least one flat region on an edge thereof. In the developed system, the wafer is spun one 360 degree turn on a chuck and the edge position is measured by a linear array to obtain a set of data points at various wafer orientation. The rotation axis may differ from wafer center by an unknown eccentricity. The flat angle is found by fitting a cosine curve to the actual data to obtain a deviation. The maximum deviation is then corrected for errors due to a finite number of data points and wafer eccentricity by calculating an adjustment angle from data points on the wafer fiat. After determining the flat angle the wafer is spun to the desired orientation. The wafer eccentricity can be calculated from four of the data points located away from the flat edge region. and the wafer is then centered.

• Journal of Korean Ophthalmic Optics Society
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• v.16 no.1
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• pp.107-116
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• 2011

Purpose: The review article was written to establish an excel program that could calculate minimal Dk of contact lens without $O^2$ deficiency and actual $O^2$ concentration on cornea when contact lens were being fitted by changing lens-related factors. Methods: An excel program was formulated to calculate the thickness of post-lens lacrimal layer, Dk of contact lens and $O^2$ concentration on cornea. Results: With the excel program established, minimal $O^2$ concentration needed on cornea could be calculated when the thickness of post-lens lacrimal layer was changed by varying lens-related factors. A different route in the excel program was needed to choose based on the shape of lacrimal layer. The thickness of lacrimal layer was determined by the shape of meniscus made of tear between lens edge and cornea with flat fit. Thus, the $O^2$ concentration showing negative number in calculation decreased on peripheral cornea with flatter fitting and actual $O^2$ concentration would be zero on cornea. With tight fitting, the thickness of post-lens lacrimal layer is much thicker than lens itself thus negative number in calculation by the excel program is shown indicating zero oxygen on cornea. It can cause $O^2$ deficiency regardless of Dk of contact lens. Conclusions: The calculation of thickness of post-lens lacrimal layer and $O^2$ concentration on cornea by the established excel program is suggested to avoid $O^2$ deficiency when fitting state is varied by changing lens-related factors.

• Korean Journal of Human Ecology
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• v.15 no.3
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• pp.481-490
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• 2006

Adjusting pressure level in the construction of athletes' tight-fitting garments by reducing the elastic knit pattern is a challenging subject, which influences the performance of the wearer directly. Therefore, in this study, relationship between the reduction rates of the basic pattern obtained from 3D human scan data and resultant clothing pressure was explored to improve the fit and pressure exerted by clothing. 3D scan data were obtained using Cyberware and they were transformed into a flat pattern using software based on Runge-Kutta method. Reduction rate was examined by subjective wear test as well as objective pressure measurement. As a result, difference in the length between the original 3D body scan data and the 2D tight-fitting pattern was 0.02$\sim$0.50cm (0.05$\sim$1.06%), which was within the range of tolerable limits in making clothes. Among the five garments, the 3T-pattern was superior in terms of subjective sensation and fit. The pressure of the 3T pattern was 2$\sim$4 gf/cm2 at five locations on the body, which is almost the same or a bit higher than that of Z-pattern. In the case of tight-fitting overall garment, the reduction rate of the pattern in the wale direction is more critical to the subjective sensation than the course direction. It is recommended that the reduction grading rules of course direction should be larger than that of Ziegert for a better fit of tight-fitting garments. In the case of wale direction, however, reduction grading rule should be kept the same as suggested earlier by Ziegert (1988).

• Science of Emotion and Sensibility
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• v.6 no.1
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• pp.17-26
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• 2003

With rapid expansion in e-retailing of apparel business, the virtual fitting model is used for comparing fit of the selected garments. The researchers experimented women's perceived body size for developing virtual fitting model. 50 women who were 20's in age were participated in the experiment They were graduate students with clothing & textile major. The results of this study showed that the subjects perceived themselves with fuller figure at waist or hips and with shorter figure at waist height than their actual body site. Many subjects believed that their body sizes were close to the average site. Especially, subjects whose abdomen girth of hip girth was much larger than average thought that they have relatively flat abdomen. It was concluded that not only the user's body measurements but also user's perception on their figure type are needed to be considered in the process of developing virtual fitting model for e-retailing of apparel. It was expected that the virtual fitting model of extraordinary size body would not be accepted by the female consumers even though they are extra large or small size person in reality.