• Journal of Technologic Dentistry
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• v.34 no.2
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• pp.135-143
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• 2012

Purpose: The purpose of this in vitro study was to compare the marginal fit of POM restorations with 3 different thickness of metal coping. Methods: 2.0mm Occlusal reduction, 1.0mm preparation of axial wall with 6degree taper, and chamfer margin was prepared a maxillary first premolar on dentiform. Duplicate prepared die and, make 30 individual dies with Ni-Cr metal. Make 3 groups of 30 press ceramic on Metal crown with different thickness of metal coping; 10 of 0.1mm, 10 of 0.3mm, 10 of 0.5mm thickness metal coping. The marginal fit of the crowns was evaluated 50 points per 1 crown, around the crown margin circumference under a optical microscope at original magnification ${\times}100$. A 1-way analysis of variance (ANOVA) was used to compare data. Results: The mean marginal discrepancy for POM with 0.1mm metal copings was $72.56{\mu}m$, $67.83{\mu}m$ for 0.3mm metal coping POMs, and $72.56{\mu}m$ for 0.5mm metal coping POM. The 1-way ANOVA showed significant difference among 3 groups. Conclusion: The marginal fit of pressed-on-metal (POMs) was best with 0.3mm thickness of metal coping, fallowing by 0.1mm, and 0.5mm in the order.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.65-67
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• 2015

In this paper, small WLAN antenna was designed and investigated. Proposed antenna was configured for microstrip patch antenna ($29mm{\times}29mm$) that was mounted on RF4 dielectric substrate (relative permittivity 4.4, thick 1.6mm, tangent loss 0.025) with $45mm{\times}45mm$. In order to obtain a wide band characteristic, the cutting process was 3.2mm diagonal corners of the patch antenna located on the top of the substrate. Antenna feeding position for 50 ohm impedance matching was decided to be 5.1mm at the central axis in the horizontal direction. As a result, frequency bandwidth satisfying the condition of VSWR<2dB was 2.365-2.45GHz (85MHz, 3.53%) for considering WLAN.

• Journal of Korean Ophthalmic Optics Society
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• v.5 no.2
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• pp.139-144
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• 2000

In this study, anterior corneal radius of curvature in korean subjects aged between 16 to 79 year-olds were measured using a keratometer. Refractive power was also measured without cyloplegia. A-mode Ultrasonography was used to measure anterior chamber depth, crystalline lens thickness, vitreous chamber depth & axial length. Measurements of anterior chamber depth of subjects in their 20s were between 3.0 mm & 4.0 mm, 70s age group were between 2 mm & 3.50 mm, showing a decrease with age. Crystalline lens thickness of 20s age group was 2.64 mm while 70s age group was 4.62 mm showing an increase with age. Vitreous chamber depth, unaffected by age, was about 17 mm. Axial length was 24.47 mm in subjects below 40s age groups decreasing to 24.11 mm in above 40s age groups. Corneal radius of curvature was 7.79 mm and 7.72 mm in younger and older age groups respectively, showing a decrease with age.

• Development and Reproduction
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• v.22 no.1
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• pp.39-53
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• 2018

The purpose of this study is to investigate the early life history of the Rhodeus fish, Rhodeus uyekii and R. ocellatus, in the Nakdong River to use as the preliminary data for the systematic study. The embryos used in the study were fertilized eggs (embryo) and larvae after artificial fertilization. The long diameter of the eggs of the R. uyekii was 3.39-3.97 mm (average $3.68{\pm}0.41mm$, n=30) and the short diameter was 1.36-1.55 mm (average $1.45{\pm}0.13mm$, n=30). The long diameter of the eggs of the R. ocellatus was 2.53-2.71 mm (average $2.62{\pm}0.12mm$, n=30) and the short diameter was 1.47-1.60 mm (average $1.53{\pm}0.09mm$, n=30). Hatching time was 48 hours for the R. uyekii and 50 hours for the R. ocellatus given that the average water temperature was $21.5^{\circ}C$. The hatched larvae were 4.95-5.00 mm (average $4.98{\pm}0.04mm$, n=5) for the R. uyekii and the total length was 3.66-3.69 mm (average $3.67{\pm}0.02mm$, n=5) for the R. ocellatus. R. uyekii was found to be 15.5-15.8 mm at total length (average $15.6{\pm}0.21mm$, n=5) on the 56 days after hatching with the number of dorsal fins being ⅲ-9, anal fins ⅲ-10, ventral fins ⅲ-5. The R. ocellatus was found to be 15.8-16.0 mm (average $15.9{\pm}0.14mm$, n=5) at total length on the 58 days with the number of dorsal fins being ⅲ-11, anal fins ⅲ-12 and ventral fins ⅲ-5 where the number of all fin stalks reached maximum.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.6
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• pp.96-101
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• 2020

In this paper, we present the results of our research to perform 3D laser scanning functions by adding a focusing lens to a conventional 2D laser scanner. For the optical design, the ray-tracing technique was used along with a total of four lenses as the variable incident focusing lens, the collimating lens, and the F-Theta lens. As design variables, the curvature of the incident focusing lens (Lens #1) was assumed to be us, l mm and sumed mm, and the incident angles were set at 0cidenus, l. In addition, the distance between the focusing lens and the collimating lens was set to vary from 5 mm to 15 mm. When the incident focal length was varied from 5 mm to 15 mm, the exit focal length was calculated to vary from 67.5 mm to 56.8 mm for the lens with R = 100 mm and from 108.5 mm to 99.0 mm for the lens with R = 150 mm. When the incident angle was 0°, the focal aberration was only slightly observable at 10㎛ in both the x- and y-direction. At 7.5° was the focal aberration of approximately 20~50㎛ was measured at 20㎛. To investigate the chromatic aberration of the designed optical device, the distortion of the focus was observed when the 550 nm beam was simulated on lens designed for a 980 nm wavelength.

• Korean Journal of Ichthyology
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• v.32 no.4
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• pp.222-231
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• 2020

The egg development and early life history of Sharpbelly Hemiculter leucisculus were investigated. For the experiments, the mature adults were collected at the Lake Yedang in Korea. The eggs from the females were obtained by injecting 10 IU/g of human chorionic gonadotropin and inseminated by wet method in the laboratory. The fertilized eggs were 0.97±0.02 mm (0.9~1.0 mm n=30) in diameter. The embryo began to hatch about 32 hrs after fertilization under water temperature of 22±1℃. The newly-hatched larvae were 3.0±0.2 mm (2.6~3.4 mm, n=15) in total length, and they haven't Melanophore. Six days after hatching, the Preflexion larva were 5.7±0.1 mm (5.4~5.8 mm, n=15) in total length, and they began to eat a Rotifer. 17 days after hatching, the Flexion larva were 6.8±0.2 mm (6.5~7.0 mm, n=15) in total length, and a gas bladder develop above the intestine. 30 days after hatching, the Postflexion larva were 8.8±0.7 mm (7.9~10.3 mm, n=15) in total length, three dorsal fin rays began to develop in the membrane fins. 50 days after hatching, the Juvenile were 20.8±0.8 mm (18.8~24.6 mm, n=15) in total length, and all their fin-rays were formed.

• The Journal of Korean Society for Radiation Therapy
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• v.33
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• pp.25-33
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• 2021

Purpose : The purpose of this study is to evaluate the accuracy and usefulness of the Trigger mode for the Respiratory Gated Radiation Therapy (RGRT) Materials and methods : A QUASAR respiratory phantom that inserted a 3 mm fiducial marker (a gold marker) was used to estimate the accuracy of the Trigger mode. And the 20 bpm was used as reference respiration rate in this study. The marker that placed at the center of the phantom was contoured, and the lower threshold of a gating window was fixed at 2.0 mm using an OBI with Truebeam STx^TM. The upper threshold was measured every 0.5 mm from 1.0 mm to 3.0 mm. The respiration rates were changed every 10 bpm from 10 bpm to 60 bpm. We repeatedly measured five times to check the error rate of the trigger mode in the same condition. Result : The differences of a distance from a peak phase to upper threshold, 1.0 to 3.0 mm at a 20 bpm as a reference for 3 days in a row were 0.68±0.05 mm, 0.91±0.03 mm, 1.23±0.03 mm, 1.42±0.04 mm, and 1.66±0.06 mm, respectively. Measurement result of changes in respiratory rate compared to baseline respiratory rate in maximum absolute difference. The coefficient of determination (R2) to estimate the correlation between the respiration velocity and variation of absolute difference was on average 0.838, 0.887, 0.770, 0.850, and 0.906. The p-values of all the variables were below 0.05. Conclusion : Using Trigger mode during respiratory gated radiation therapy (RGRT), accuracy and usefulness of trigger mode at reference breathing rate were confirmed. However, inaccuracies depending on the rate of breathing it could be uncertain in case of respiration rate is faster than 20 bpm as a standard respiration rate compared to slower than 20 bpm. Consequently, when conducting a RGRT using the trigger mode, real time monitoring is required with well educated respiration.

• Journal of Environmental Science International
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• v.24 no.3
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• pp.317-322
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• 2015

The photocatalytic decomposition characteristics of toluene, acetone, and methyl mercaptan (MM) by UV reactor installed with $TiO_2$-coated perforated plane were studied. The removal efficiency of single toluene, acetone, and MM vapor was increased with increasing oxygen concentration, but decreased with increasing inlet concentration. Elimination capacity of single toluene, acetone, and MM vapor was obtained to be $628g/m^3{\cdot}day$, $1,041g/m^3{\cdot}day$, and $2,158g/m^3{\cdot}day$, respectively. Also, the photocatalytic decomposition of binary vapor consisted of toluene and acetone, toluene and MM, acetone and MM were observed. Elimination capacity of toluene mixed with acetone, toluene mixed with MM, acetone mixed with toluene, acetone mixed with MM, MM mixed with toluene, and MM mixed with acetone was $327g/m^3{\cdot}day$, $512g/m^3{\cdot}day$, $128g/m^3{\cdot}day$, $266g/m^3{\cdot}day$, $785g/m^3{\cdot}day$ and $883g/m^3{\cdot}day$, respectively. The inhibitory effect of acetone was higher than MM in photocatalytic decomposition of toluene, the inhibitory effect of toluene was higher than MM photocatalytic decomposition of acetone, and the inhibitory effect of toluene was higher than acetone in photocatalytic decomposition of MM.

• Journal of Veterinary Clinics
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• v.39 no.6
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• pp.319-325
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• 2022

Two-port laparoscopic ovariectomy (Lap-OVE) has been performed in small dogs, using 3-mm and 5-mm portal sites, and is associated with reduced surgical stress and postoperative pain. However, extension of the incision is often needed to extract the ovaries. In this study, we aimed to minimize invasiveness by using smaller-sized cannulas as well as a novel technique for ovary extraction. Lap-OVE was performed on six, healthy female dogs (range, 3 to 7.2 kg) using two 3-mm midline portals. The middle finger of a size M nitrile glove was cut at its base and sterilized preoperatively. The ovary was suspended at the body wall using a 1-0 blue nylon needle, and the ovarian pedicle and ligaments were transected using a 3-mm bipolar forceps. To facilitate the glove passing through the 3.9-mm port, it was turned inside out to expose the smooth inner surface, before being inserted into the abdominal cavity with an applicator. Both ovaries were placed inside, and the mouth of the glove was exteriorized through the port with a laparoscopic grasping forceps. The ovaries were morcellated inside the glove, using Adison-Brown tissue forceps and iris scissors, which enabled safe extraction without incision enlargement. Median incision lengths were 4.3 mm (3.5-mm cranial cannula) and 4.8 mm (3.9-mm caudal cannula). An advantage of this procedure was that there was no need for skin sutures. In conclusion, using our novel technique, sutureless Lap-OVE was possible in small dogs using two 3-mm portal sites without additional incision.

• Korean Journal of Ichthyology
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• v.26 no.4
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• pp.267-273
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• 2014

This research has carried out to make a data base of taxonomic research. That Data base explains about spawning behavior, egg development, and morphologic development of variable sabretooth blenny. Fertilized egg was demersal egg which is white and opaque. The number of oil glouble were 10~11, and the size of egg was 0.90~1.43 mm (average rate $1.11{\pm}0.23mm$, n=10). Breeding water temperature was $25.5{\sim}28.5^{\circ}C$ (average rate $27.0^{\circ}C$), and salinity was 32.5~33.5‰ (average rate 33.0‰). After 24 hours from 2 cells, the process of egg development was reached to Blastula stage. Moreover, after 330 hours from 2 cells, nostrils and eyes were formed. Egg membrane was pierced by the head, and the hatch began. After the hatch, postlarvae had 2.59~3.02 mm (average rate $2.81{\pm}0.25mm$, n=5) of whole length, and the mouth and anus were opened. Yolk sac and oil glouble were absorbed. After three days from hatch, prelarvae were 3.02~3.07mm(average rate $3.04{\pm}0.04mm$) of whole length, and caudal fin was grown with round shape. After 13 days from hatch, prelarvae had 3.04~3.20 mm (average rate $3.12{\pm}0.11mm$) of whole length, and they could eat food with upper jaw and bottom jaw.