• Korean Journal of Optics and Photonics
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• v.34 no.1
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• pp.13-21
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• 2023

We have investigated the acceptance angle and imaging performance of a curved artificial compound eye (ACE), depending on the sag height of the microlens array to maximize its sensitivity to light. When the h/r values increased from 0.22 to 0.37, the acceptance angle of the curved ACE was expanded from 28.70° to 49.02°, which is an enhancement by 70.8%. With the designed optical system, it was demonstrated that a microlens located at the 23rd position from the center of the main lens could still focus an incident beam tilted at 56.35°, so that the letter F was clearly observed.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.2
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• pp.84-95
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• 2014

Recently, as a variety of techniques of CMF (Compressed media filter) that has advantages of high porosity and compressibility have been developed in the U.S. and Japan. Therefore, the interest of intensive wastewater treatment using CMF has grown. This study examined the feasibility of CMF with varying sewage water quality to determine the optimum operating conditions. A preliminary tracer test that investigated the filtering process under various compression and flow rate conditions was performed. In a high compression condition, different porosities were applied to each depth of the column. Therefore, a distinct difference between a theoretical value and results of tracer test was observed. For the TSS (Total suspended solid) removal and particle size distribution of CMF for pre-treatment water under the various compression conditions, the compression ratio of 30 percent as the optimal condition showed greater than 70% removal efficiency. In addition, the compression ratio of >15% was required to remove small-sized particles. Also, an additional process such as coagulation is necessary to increase the removal efficiency for < $10{\mu}m$ particles, since these small particles significantly influence the effluent concentration. Modeling results showed that as the compression rate was increased, TSS removal efficiency in accordance with each particle size in the initial filtration was noticeably observed. The modeling results according to the depth of column targeting $10{\mu}m$ particles having the largest percentage in particle size distribution showed that 150-300 mm in filter media layer was the most active with respect to the filtering.

• Journal of Korean Physical Therapy Science
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• v.10 no.1
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• pp.190-197
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• 2003

This study was designed to investigate the function of estrogen in related with the effects of the antiestrogen on morphologic changes of efferent ductules of the adult male mouse. Estrogen is synthesized in the male reproductive system and is found in high concentrations in rete and seminal fluids. Adult male mice, 30 days old, were injected subcutaneously with ICI(5mg/mouse) once per week for 8 weeks. Tissues were fixed by vascular perfusion on days 8, 10, 12, 14, 16, 25 and 59 post-treatment. The lumen of efferent ductules began to dilate from the day 8 and continued to the day 59 post-treatment. Epithelial cell height in the efferent ductules of the treated mice decreased all the time periods, compared to the control. Cell height in proximal region of the efferent ductules in the treated groups decreased most by 38%. Supranuclear cytoplasmic height in epithelial cell of the ducts also showed the decrease of 46%, 39% and 33% in proximal, conus and common regions in the treated groups, respectively. ICI 182,780 treatment in the male mouse reproduced a similar morphological abnormalities that were observed in the efferent ductules of the ${\alpha}ERKO$ mouse.

• Journal of the Korean Electrochemical Society
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• v.3 no.4
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• pp.200-203
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• 2000

Boron doped conducting diamond thin films were grown on Si substrate by microwave plasma chemical vapor deposition from a gaseous feed of hydrogen, acetone/methanol and solid boron. The doping level of boron was ca. $10^2ppm\;(B/C)$. The Si substrate was tilted ca. $10^{\circ}$ to make Si substrate, which have different height and temperature. Experimental results showed that different crystalline of diamond thin films were made by different temperature of Si substrate. There appeared $3\~4$ steps of different crystalline morphology of diamond. To characterize the boron-doped diamond thin film, Raman spectroscopy was used for identification of crystallinity. To survey surface morphology, microscope was used. Grain size was changed gradually by different temperature due to different height. The Raman spectrum of film exhibited a sharp peak at $1334cm^{-1}$, which is characteristic of crystalline diamond. The lower position of diamond film position, the more non-diamond component peak appeared near $1550 cm^{-1}$.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.2
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• pp.119-124
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• 2009

Statement of problem: The increasing demand for esthetic restorations has been required developing new materials for tooth colored restoration. Ceromer(Ceramic Optimized Polymer) has some advantages over porcelain, and has gained increasing popularity in restorative dentistry. However, there is little information on the dimensional changes in a clinical restoration in moist conditions. Purpose: This study examined the dimensional changes in Ceromer restorations with a clinical crown shape that were fabricated in a clinical manner. Material and methods: The crowns for the maxillary central incisor were fabricated with two Ceromers($BelleGlass^{(R)}$ and $Targis^{(R)}$) using a similar clinical restoration manufacturing technique. A total of twenty specimens were prepared and immersed in distilled water at room temperature to allow for water absorption. The weight, height and width were measured at 24, 72 and 168 hours. The accumulated ratios of the changes were calculated and evaluated using a paired t-test and an independent independent t-test. Results: The dimensions and weight increased with increasing soaking time. $Targis^{(R)}$ showed significant differences in height and weight between 24 hours and the other times(P<.05). $BelleGlass^{(R)}$ showed significant differences in width and weight between 24 hours and the other times. The two materials showed different changing patterns of the dimensions but there were no statistically significant differences between them. Conclusion: The dimensions and weight of the Ceromer restorations were changed by water absorption. The clinical crown shaped specimen showed more complicated dimensional changes than the simplified specimens.

• Korean Journal of Veterinary Research
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• v.36 no.4
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• pp.991-995
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• 1996

Renal size(length, width and height) of rabbits was measured by radiographs and nephrosonograms and compared with actual size. After measuring on the radiographs and nephrograms, both kidneys were removed from the body and actual size was also measured. On radiographs, right kidney was observed at the T13-L2 vertebrae and left kidney was at L2-L4 vertebrae. On nephrosonograms, the renal cortex was visible as small, homogenous echoes that were hypoechoic relative to the surrounding tissues, whereas the renal medulla was anechoic to slightly hypoechoic. The actual length, width and height of the left kidney were $35.84{\pm}3.12(mean{\pm}SD)$, $23.52{\pm}3.21$, $15.11{\pm}2.58cm$, respectively, whereas those of the right kidney were $36.02{\pm}3.42$, $23.69{\pm}3.50$ and $14.13{\pm}3.55cm$, respectively. On radiographs, the length and width of both kidneys were a little magnified(102-104%) when compared to actual size. On nephrosonograms, the length, width and height of bothkidneys were lessened(70-96 %) when compared to actual size. The length and width of kidney were 1.85 and 1.25 times the length of the second lumbar vertebrae on the ventrodorsal view. In correlation and correlation coefficient of body weight with the renal size, the body weight and renal size were significantly correlated with each other other(p<0.01) and the correlation coefficents of body weight with left, right and both Kindneys were 0.748, 0.794 and 0.859, respectively.

• Journal of the Korean Society for Nondestructive Testing
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• v.25 no.4
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• pp.247-253
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• 2005

This study investigated the effects on foot and ankle roll-over characteristics according to different heel heights during walking. Fifteen female volunteers who have neither musculoskeletal nor foot problems were participated in gait analyses, wearing four different pairs of shoes in different heel heights. To obtain roll-over shape of foot/ankle complex, we used trajectories of knee and ankle joints as well as the renter of pressure between initial contact and opposite initial contact. Results revealed that the entire roll-over shape moved distally as the heel height increased but roll-over characteristics showed uniformly with different heel heights. In addition, we found that nondisablea persons automatically adapted to their foot/ankle complex to varying heel heights within 6cm, by moving the origin of roll-over shape distally to maintain roll-over characteristics. However, since the balance of the gait only by the ankle joint could not be achieved beyond the heel height of 6cm, compensations at the knee and the hip joints occurred simultaneously. Roll-over characteristics in human walking would provide simpler and wider understanding of human walking, and furthermore could be applied to the wide understanding of prosthetics and orthotics of the lower extremity as well as orthopaedic shoes.

• Journal of the Korean Vacuum Society
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• v.16 no.3
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• pp.197-204
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• 2007

Ultra thin Er-silicide layers formed by Er deposition on the clean p-silicon and in situ post annealing technique were investigated with respect to change of the Schottky barrier height. The formation of Er silicides was confirmed by XPS results. UPS measurements revealed that the workfunction of the silicide decreased and was saturated as the deposited Er thickness increased up to $10{\AA}$. We found that the silicides were mainly composed of Er5Si3 phase through the XRD experiments. After Schottky diodes were fabricated with the Er silicide/p-Si junctions, the Schottky barrier heights were calculated $0.44{\sim}0.78eV$ from the I-V measurements of the Schottky diodes. There was large discrepancy in the Schottky barrier heights deduced from the UPS with the ideal junction condition and the real I-V measurements, so that we attributed the discrepancy to the $Er_5Si_3$ phase in the Er-silicides and the large interfacial density of trap state of it.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.3
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• pp.433-439
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• 2009

The purpose of this study was to assess the effect on mandibular growth of botulinum toxin type A (BTXA) injection into the unilateral massester muscle of growing rats at three different growing stages. Thirty six male Sprague-Dawley rats were divided into three groups according to the age (group 1: 4 week-old, group 2: 5week-old, group 3: 6week-old). Then each group was randomly divided into 3 subgroups (control group, unilateral injection group, bilateral injection group). Experimental animals were sacrificed after 4 weeks. Then the jaw measurements were evaluated. The results were as follows: 1. In the group 1, mandibular body length, condylar height and coronoid process height of the unilateral group(BTXA side) and the bilateral group were shorter than those of the control group (p<0.05). 2. In the group 2, anterior region height, condylar height, coronoid process height of the unilateral group(BTXA side) and the bilateral group were shorter than those of the control group (p<0.05). 3. In the group 3, mandibular body length, condylar height, coronoid process height of the unilateral group(BTXA side) and the bilateral group were shorter than those of the control group (p<0.05). 4. There was no significant difference in mandibular measurements between the control side and the injection side in the unilateral group in all age groups (p>0.05).

• Korean Journal of Organic Agriculture
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• v.25 no.1
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• pp.85-99
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• 2017

The study was compared for ability to supply macro-nutrients between time and height of mowing to establish alternate technique of a chemical fertilizer with 9-year old 'Niitaka' pear (Pyrus pyrifolia Nakai) trees in a pesticide-free orchard in 2009. Rye and hairy vetch were sown together during fall 2008. Four types of mowing time treatments were included; mowing on April 18+May 28, on April 28+June 8, on May 8+June 18, and on April 18+May 18+June 18. Mowing height treatment included mowing at $3{\pm}1cm$, $7{\pm}1cm$, and $13{\pm}1cm$ on April 18 or June 8. Mowing on May 8+June 18 increased the most dry weight of ground cover and vegetation to 14,480 kg per ha among the mowing time treatments, resulting in the greatest production of T-N (total nitrogen; 292 kg) and K (396 kg) per ha on the soil. Mowing at $7{\pm}1cm$ decreased the most dry weight of ground cover and vegetation to 11,970 kg per ha among the mowing height treatments, resulting in the lowest production of T-N (265 kg), P (111 kg) and K (333 kg) per ha in a soil. Ground cover treatments increased soil organic matter contents, regardless of mowing treatment methods.