• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.3
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• pp.271-282
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• 2012

Early osteological development of the skull, vertebral column, and fins, and squamation in the spotted sea bass, Lateolabrax maculates, were studied under extensive larval rearing conditions. The first ossification during cephalic skeleton development began with the premaxillary, dentary, and parasphenoid at 6.4 mm Total length (Notochord length 6.1 mm) and was completed by 25.2 mm TL (Standard length 20.3 mm). Ossification of the cartilaginous caudal complex started simultaneously in the urostyle and two preural centra at 12.2 mm TL (10.4 mm) and it was completely ossified by 32.0 mm TL (26.4 mm). The principal caudal fin rays, with a count of 9/8, began to ossify at 11.6 mm TL (10.2 mm) and the procurrent caudal fin rays, with counts of 4 (upper) and 3 (lower), started to ossify by 12.6 mm TL (10.9 mm). Ossification of these parts was completed by 21.4 mm TL (17.5 mm). Ossification of the vertebral column was first observed in the first to fourth centra at 8.3 mm TL (7.5 mm) and was fully completed by 21.7-35.0 mm TL (17.8-29.3 mm). The pectoral girdle started to ossify by 5.6 mm TL (5.4 mm) and was completed by 26.8 mm TL (21.8 mm). Eight pectoral fin rays were ossified at 11.6 mm TL (10.2 mm) and 16-18 rays were fully ossified by 13.8 mm TL (12.0 mm). Also, the dorsal, anal, and pelvic fin rays started to ossify at 12.2 mm TL (10.4 mm) and were completed by 12.8 mm TL (11.2 mm), 23.8 mm TL (19.4 mm), and 13.8 mm TL (12.0 mm), respectively. Ossification of the anal and dorsal pterygiophores initially occurred by 12.6 mm TL (10.9 mm) and 14.3 mm TL (12.2 mm), and was completed by 21.4 mm TL (17.5 mm) and 19.3 mm TL (15.9 mm), respectively. Squamation started at three centers of differentiation: the middle region of the trunk, the anterior of the caudal peduncle, and on the caudal peduncle at 23.8 mm TL (19.4 mm). The body was covered with scales, except the snout, at 57.2-60.2 mm TL (SL 47.1-49.2 mm).

• Journal of Korean Ophthalmic Optics Society
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• v.1 no.2
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• pp.71-76
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• 1996

As the results of measurement of the radius of corneal curvature with keratometer, for the right eye of 91 male adults, horizontal radius is 7.16 mm to 8.49 mm and vertical radius is 7.03 mm to 8.34 mm, and for the left eye of male adults, horizontal radius is 7.10 mm to 8.48 mm and vertical radius is 7.01 mm to 8.24 mm. In case of 61 female adults, horizontal radius is 7.16 mm to 8.45 mm, vertical radius 7.11 mm to 8.18 mm for the right eye, and horizontal radius 7.15 mm 108.43 mm and vertical radius 7.01 mm to 8.26 mm for the left eye. The mean value of radius of corneal curvature is 7.74 mm for male and 7.69 mm for female. Also the mean value of horizontal radius is 7.79 mm and vertical radius is 7.64 mm. Overall mean value of the radius of corneal curvature is 7.71 mm that is corresponded to Gullstrand's eye. The horizontal radius is 0.15 mm bigger than vertical radius.

• Journal of IKEEE
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• v.20 no.2
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• pp.123-127
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• 2016

In this study, gamma radiation detectors are created by integrating the following combinations of different YSO scintillators and PMT(photomultiplier-tubes) respectively: $3mm{\times}3mm{\times}2mm$, $3mm(Dia){\times}15mm$, $3mm(Dia){\times}20mm$, $10mm(Dia){\times}20mm$. In addition, the scintillator with a 10mm diameter was integrated with a light guide with a 2mm thickness, 10mm entry and 3mm exit, using LightTools. The constructed detector used the standard gamma ray sources $^{137}Cs$(662keV) to analyze the spectral characteristics of gamma rays. The results indicate that at 662keV, the energy resolutions were 14.46%, 21.10%, and 10.71% for the first three combinations respectively. The best results were recorded for the $10mm(Dia){\times}20mm$ detector with light guide, which had an energy resolution of 7.48%.

• Journal of Korean Ophthalmic Optics Society
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• v.5 no.1
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• pp.1-6
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• 2000

This study was to calculate spot size, focus shift and optical focus by use of OSLO when 3 wavelength, ${\omega}{\upsilon}_1=0.588{\mu}$, ${\omega}{\upsilon}_2=0.486{\mu}$ and ${\omega}{\upsilon}_3=0.656{\mu}$ in composite lens optics system & ocular optical system were respectively here, Entrance Beam Radius(mm) 1 mm, Field angle(deg) 5.7296e-0.5 mm, Image Aperture 0.053055 mm, Exit Aperture 0.903711 mm, Reflective focal length 25.181544 mm, Petzval radius -19.21839 mm, n = 1.523. It was found that a range of spot size was 0.002 mm~0.07 mm when a range of back curvature radius was 1 mm~30 mm, and 0.0005 mm~0.002 mm when of it more than 50 mm. Focus shift, 50 mm a range 3 kinds of lens was small, and it saw that of all tendency was high up to 1 mm~15 mm and up to 25 mm beyond that limits, it was going down and then going up again, optical focus 100 mm lens was best and the value when optimization with this lens was $60{\pm}1mm$.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.6
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• pp.84-89
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• 2015

The thickness of a stable and economical frame has been designed in order to reduce costs. Therefore, this study applied structural analysis and vibration analysis based on a comparison of the thicknesses of frames. Four types of frames (1mm, 2mm, 3mm, and 5mm) were modeled on a bicycle frame that has a length of 842mm, a width of 100mm, and a height of 400.5mm, and all of these frames generated the stress and maximum deformation amount in the state and around the saddle. The maximum stress shown was 25.732 MPa in 1mm, 11.79 MPa in 2mm, and 8.2015 MPa in 3mm, and the maximum deformation amount shown was 0.063611mm in 1mm, 0.031978mm in 2mm, and 0.022319mm in 3mm. The natural frequency of the frame thicknesses 1mm, 2mm, and 3mm was estimated as within 270 Hz. The critical frequency of conditions of 3mm was the biggest at 118.1Hz compared with the 3-mm model; thus, 3mm was shown to have the most satisfactory resistance.

• The Journal of Korean Society for Radiation Therapy
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• v.29 no.2
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• pp.75-81
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• 2017

Purpose: To evaluate the reproducibility of image-guided radiotherapy using ultrasonography which is non-invasive, without radiation exposure for prostate cancer patients. Materials and Methods: We analyzed the setup variation of 1,105 images for 26 prostate cancer patients and the mean, standard deviation and 3D-error in AP, RL and SI directions. Setup variations were classified 0-1 mm, 1-3 mm, 3-5 mm, 5 mm and more. Results: The mean and standard deviation of setup variation in AP, RL and SI directions was $1.87{\pm}1.36mm$, $1.73{\pm}1.22mm$ and $2.01{\pm}1.40mm$. The 3D-error in AP, RL and SI directions was $3.63{\pm}1.63mm$. The frequency of setup variation in AP direction was 29 % in the range from 0 mm to 1 mm, 50.2 % in the range from 1 mm to 3 mm, 19.6 % in the range from 3 mm to 5 mm and 1.3 % in the range of 5 mm or more. In RL direction, the frequency was 31.3 % in the range from 0 mm to 1 mm, 52.5 % in the range from 1 mm to 3 mm, 15.8 % in the range from 3 mm to 5 mm and 0.5 % in the range of 5 mm or more. SI direction, the frequency of errors in the range from 0 mm to 1 mm was 26.3 %, 50.2 % in the range from 1 mm to 3 mm, 22.4 % in the range from 3 mm to 5 mm, and 1.1 % in the range of 5 mm or more. Conclusion: The setup error was highest in the SI direction of $2.01{\pm}1.40mm$. The frequency in each direction was the highest in more than 50 % in the range from 1 mm to 3 mm. $Clarity^{TM}$ Auto scan is possible to monitoring the motion of the prostate during the treatment and to repositioning the patient. In conclusion real-time image-guided radiotherapy using ultrasonography will be increase the reproducibility of radiation therapy.

• Structural Engineering and Mechanics
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• v.67 no.5
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• pp.505-516
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• 2018

In this paper, the effects of particle size and model scale of concrete has been investigated on the failure mechanism of PFC2D numerical models under uniaxial compressive test. For this purpose, rectangular models with same particle sizes and different model dimensions, i.e., $3mm{\times}6mm$, $6mm{\times}12mm$, $12mm{\times}24mm$, $25mm{\times}50mm$ and $54mm{\times}108mm$, were prepared. Also rectangular models with dimension of $54mm{\times}108mm$ and different particle sizes, i.e., 0.27 mm, 0.47 mm, 0.67 mm, 0.87 mm, 1.07 mm, 1.87 mm and 2.27 mm were simulated using PFC2D and tested under uniaxial compressive test. Concurrent with uniaxial test, direct shear test was performed on the numerical models. Dimension of the models were $75{\times}100mm$. Two narrow bands of particles with dimension of $37.5mm{\times}20mm$ were removed from upper and lower of the model to supply the shear test condition. The particle sizes in the models were 0.47 mm, 0.57 mm, 0.67 mm and 0.77 mm. The result shows that failure pattern was affected by model scale and particle size. The uniaxial compressive strength and shear strength were increased by increasing the model scale and particle size.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.41 no.1
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• pp.21-28
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• 2017

Indirect evaporative cooling, which utilizes a cooling effect obtained by the evaporation of water, is energy-effective compared to the conventional vapor compression method. It is also eco-friendly, due to the non-usage of CFC refrigerant. In this study, three indirect evaporative cooler samples of the cross flow type(size: $300mm{\times}300mm{\times}300mm$, channel pitch: $5mm{\times}5mm$, $5mm{\times}7mm$, $7mm{\times}7mm$) were made using plastic/paper composites. Tests were conducted to measure indirect evaporative efficiencies and pressure drops. Results showed that the efficiency was the highest for the $5mm{\times}5mm$ sample, owing to the largest surface area. The saved electrical energy was also the greatest for that sample. The pressure drop of the wet channel was larger than that of the dry channel as expected. A theoretical model was proposed, which underestimated both the indirect evaporation efficiency and the pressure drop.

• Journal of Korean Ophthalmic Optics Society
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• v.2 no.1
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• pp.25-30
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• 1997

The palpebral fissures of 1529 healthy Koreans ranging in age from one month to 92 years were examined. The length and width of palpebral fissure, distance of folded upper lid(FUL), inter outer canthal distance(IOCD) and appearance of double upper lid (DUL) were studied. The most commonly occuring length of the normal palpebral fissure was 30 mm(13.7%) followed by 28 mm(9.8%) and 27 mm(8.8%), and almost four fifths(79.1%) of the palpebral fissures measured less than 30mm in length. Of the ages 11~60 examined over 70 % averaged palpebral fissures measuring bet ween 27 mm and 32 mm. The commonest width of 1443 normal palpebral fissure was 8 mm(28.2%) followed by 9mm(16.3%) and 7mm(15.0%), and average widths according to 5 major age groups were 5~8mm, 6~10mm, 7~11mm, 7~11mm and 5~9mm, and there is some tendency to a decrease with age. The average of FUL without frontalis action was 8~11 mm. The distances between exocanthions, IOCD, according to age groups were estimated to be 77~82mm for one to 10, 94~101mm for 11 to 60 and 89~95mm for over-60 age group, respectively. The DUL was appeared in 44 % of sample, and DUL in female was more than in male.

• The korean journal of orthodontics
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• v.39 no.5
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• pp.278-288
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• 2009

Objective: The aim of this study was to investigate the changes in the center of resistance of the maxillary teeth in relation to alveolar bone loss. Methods: A finite element model, which included the upper dentition and periodontal ligament, was designed according to the amount of bone loss (0 mm, 2 mm, 4 mm). The teeth in each group were fixed with buccal and lingual arch wires and splint wires. Retraction and intrusion forces of 200 g for 4 and 6 anterior teeth groups and 400 g for the full dentition group were applied. Results: The centers of resistance were at 13.5 mm, 14.5 mm, 15 mm apical and 12 mm, 12 mm, 12.5 mm posterior in the 4 incisor group; 13.5 mm, 14.5 mm, 15 mm apical and 14 mm, 14 mm, 14.5 mm posterior in the 6 anterior teeth group; and 11 mm, 13 mm, 14.5 mm apical and 26.5 mm, 27 mm, 25.5 mm posterior in the full dentition group respectively according to 0 mm, 2 mm, 4 mm bone loss. Conclusions: The center of resistance shifted apically and posteriorly as alveolar bone loss increased in 4 and 6 anterior teeth groups. However, in the full dentition group, the center of resistance shifted apically and anteriorly in the 4 mm bone loss model.