• Journal of Korean Foot and Ankle Society
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• v.18 no.1
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• pp.14-18
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• 2014

Purpose: The purpose of this report is to evaluate the measured values of normal Korean calcaneus by conduct of a cadaveric study. Materials and Methods: A total of 42 calcanei were obtained from Korean cadavers. A digital goniometer was used for measurement of B$\ddot{o}$hler's angle, Gissane angle, posterior facet articular inclination angle, and Fowler-Philip angle of calcaneus. A vernier caliper was used for measurement of the maximal antero-posterior length, maximal transverse width, and maximal height of calcaneus. Results: The average B$\ddot{o}$hler's angle, Gissane angle, posterior facet articular inclination angle, and Fowler-Philip angle was $32.3^{\circ}{\pm}5.0^{\circ}$, $114.4^{\circ}{\pm}8.2^{\circ}$, $61.2^{\circ}{\pm}4.4^{\circ}$, and $60.3^{\circ}{\pm}7.6^{\circ}$. The average maximal antero-posterior length, maximal transverse width, and maximal height of calcaneus was $74.2{\pm}3.0mm$, $43.0{\pm}4.0mm$, and $42.5{\pm}3.0mm$. Conclusion: The measured values of normal Korean calcaneus were lower than the values reported in the international literature. Therefore, development of appropriate instruments reflecting the anatomical characteristics of Koreans will be needed.

• Journal of The Korean Society of Integrative Medicine
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• v.8 no.3
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• pp.93-101
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• 2020

Purpose : Temporomandibular joint disorder (TMJD) is often accompanied by pain and limited range of motion of the jaw joint, which affect patients' quality of life and result in hypertrophy or hyperactivity of the muscles around the jaw joint. In this study, we compared the muscle thickness and tone of the masseter and sternocleidomastoid (SCM) muscles and the jaw range of motion in individuals with and without TMJD. Correlation comparison was performed on the results of the TMJD group. Methods : This study included 40 patients; 20 patients were assigned to an experimental group (TMJD group) and 20 to a control group (non-TMJD group). Ultrasonography, myotonometry, and measurements performed with digital Vernier calipers were used to determine the changes in muscle thickness, muscle tone, and maximum jaw opening, respectively. The independent t-test was used for intergroup comparison of data, and Pearson correlation coefficients were used to compare correlations in the TMJD group results. Results : We observed a significant intergroup difference in the masseter and SCM thickness during the relaxed and clenched phases (p<.05). A significant intergroup difference was also observed in maximum jaw opening (p<.05). With regard to muscle tone, we observed a significant intergroup difference in frequency (p=.011) and stiffness (p=.011) of the masseter, as well as in the frequency (p=.009) and stiffness (p=.026) of the SCM. We observed a moderate negative correlation (r=-.524) between maximum jaw opening and the frequency of the masseter. Additionally, we observed a moderately negative correlation between jaw opening and muscle stiffness (r=-.321). Conclusion : Planning exercise programs to treat patients with TMJD who present with pain should focus on efforts to reduce muscle thickness and achieve muscle relaxation (to reduce muscle tension) for improved jaw range of motion.

• Korean Journal of Optics and Photonics
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• v.20 no.4
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• pp.217-222
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• 2009

In this paper, a low-cost hybrid-integrated tunable laser is realized using a polymer-ring resonator-based add/drop filter reflector and a reflective semiconductor optical amplifier. The add/drop filter reflector, composed of a double-ring resonator with different radii, can have characteristics of selective wavelength reflection and wide wavelength tuning with an aid of vernier effect derived from the radii difference. By hybrid-integrating the reflective semiconductor optical amplifier with the add/drop filter reflector, a tunable laser can be realized through an active alignment method. The hybrid laser exhibited a single mode lasing with side mode suppression ratio of 26 dB and full width half maximum of 0.03 nm. In addition, applying a low current as small as 25 mA onto electrodes over add/drop filter reflector, a wavelength tuning range of 17 nm could be obtained.

• Korean Journal of Optics and Photonics
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• v.22 no.2
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• pp.102-107
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• 2011

In this paper, a small double ring resonator reflector was designed and fabricated using a polymer waveguide, and the measurement result was discussed. A widely tunable characteristic of the small double ring resonator caused by the Vernier effect, which results from the difference of the ring radii, was observed. The insertion loss of the double ring reflector was reduced by minimizing the device length to be as short as possible, and thus the output power and the SMSR (side mode suppression ratio) was greatly enhanced. The hybrid integrated laser based on the small double ring resonator reflector lased with the SMSR of 45 dB. In addition, the wide tuning range of 40 nm could be obtained by injecting a current of 30 mA to an electrode on top of the reflector.

• Korean Journal of Optics and Photonics
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• v.16 no.3
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• pp.196-200
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• 2005

A 40 channel arrayed-waveguide grating (AWG) filter operating in C-band and L-band wavelength regions has been fabricated using PLC (Planar Lightwave Circuit) processes with 0.75 refractive index difference. Its design was optimized for matching the center wavelength with the ITU-recommended wavelength. The characteristics of the fabricated C-band AWG are as follows; average insertion loss < 2.5 dB, polarization-dependent loss < 0.3 dB, non-adjacent crosstalk >35dB, and the loss uniformity of 0.8 dB. In the L-band AWG, wavelength accuracy is below 0.02nm.

• 한국태양에너지학회:학술대회논문집
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• 2011.11a
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• pp.34-39
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• 2011

Screen printing method is a common way to fabricate the crystalline silicon solar cell with low-cost and high-efficiency. The screen printing metallization use silver paste and aluminum paste for front and rear contact, respectively. Especially the rear contact between aluminum and silicon is important to form the back surface filed (Al-BSF) after firing process. BSF plays an important role to reduces the surface recombination due to $p^+$ doping of back surface. However, Al electrode on back surface leads to bow occurring by differences in coefficient of thermal expansion of the aluminum and silicon. In this paper, we studied the properties of mono crystalline silicon solar cell for rear electrode with aluminum and aluminum-boron in order to characterize bow and BSF of each paste. The 156*156 $m^2$ p-type silicon wafers with $200{\mu}m$ thickness and 0.5-3 ${\Omega}\;cm$ resistivity were used after texturing, diffusion, and antireflection coating. The characteristics of solar cells was obtained by measuring vernier callipers, scanning electron microscope and light current-voltage. Solar cells with aluminum paste on the back surface were achieved with $V_{OC}$ = 0.618V, JSC = 35.49$mA/cm^2$, FF(Fill factor) = 78%, Efficiency = 17.13%.

• Fashion & Textile Research Journal
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• v.22 no.4
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• pp.504-514
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• 2020

This study improves the dimensional suitability of nail tip products by reviewing the type of fingernail as seen among adult women in Korea. Subjects were 147 adult women ranging from age 20 to 40. Direct fingernails measurements were made using digital Vernier calipers and a curvature gauge. Data on various fingernail shapes were collected through indirect measurements using photography to reveal the shape characteristics of each fingernail types. In this sense, data were analyzed by statistical methods with the use of factor analysis. There were various factors considered to classify extracted fingernail types such as five factors (for the thumb), four factors (index, middle, and little fingers), and three factors (for the ring finger). The cluster analysis resulted in three types. Type 1 is a 'Square' shape characterized with wide fingernails, low height, flat, and low curvature of the cuticle line. Type 2 is 'U-round' shape characterized with narrow fingernails, high height, convex, and the highest curvature of the cuticle line. Type 3 is a 'Round' shape in which the fingernails are wide, high in height, convex, and characterized with a medium curvature of the cuticle line. The results are useful for companies that develop the free edge shape of fingernails for consumer products. The measured values of fingernail can be applied to the shape and lake setting of the nail tip product, depending on type of fingernail.

• The Journal of the Convergence on Culture Technology
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• v.6 no.4
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• pp.825-831
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• 2020

In modern society, automobiles have become an essential means of transportation. It is the only consumable that is worn by contacting the ground among automobile parts. If the tyres are severely worn, the tyres may be break, presenting a risk of a serious accident to the driver. To avoid this risk, drivers should check tyre pressure and tread condition before driving a car. Tyre inflation pressure can be easily measured by TPMS, but in the case of tyre tread conditions, it can be cumbersome when the driver measures it directly using a coin or vernier caliper. This hassle can expose the driver to traffic accidents due to tyre breakage by neglecting to measure the condition of the tyre tread. In this paper, we introduce the contents of research to design an IoT service-based system that can automatically measure automobile tyres, and we verified the possibility of realizing the system by actually implementing and testing some components of the system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.3
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• pp.1245-1251
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• 2013

The aim of this study is to identify characteristics of 2D:4D according to type of handedness. Data was collected from October, 4th, 2010 to April, 30th, 2012. After handedness assessment, 2nd and 4th finger length were measured by vernier calipers. This study showed remarkable gender difference of 2D:4D in left hand for left handers and right hand for right handers, However, there was no significant difference according to type of handedness in each gender. The correlation between left and right 2D:4D in males right handedness was higher than that of male left handedness, otherwise, in case of female, that of left handedness was higher than that of right handedness. The results of this study suggest that the 2D:4D of left handedness does not differ from that of right handedness, however, gender difference and correlation between left and right 2D:4D show different characteristics according to handedness.

• Journal of the Institute of Convergence Signal Processing
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• v.6 no.1
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• pp.8-14
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• 2005

The implementation of vision system using CCD camera which measures the earing rate of aluminium CAN is represented in this paper. In order to optimize the input image, the object of the input image is separated and the position of the image is calibrated. In the preprocessing, the definition of image is improved by the histogram equalization, and then the edges of the input image are detected by the Robert mask. The heights of the four ears and angles of the aluminium CAN are measured manually with the digital vernier calipers in industry. It takes 30 seconds to measure manually the height of one direction of the aluminium CAN at least three times. However, when the proposed system in this paper is applied, it takes 0.02 seconds only. In conclusion, the efficiency of the proposed system is higher than that of the system used in the industry.