• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.224-224
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• 2016

수문 순환과 물 수지에 관한 연구는 강수량, 지표유출량, 지하수, 토양수분 및 증발산량 등에 대한 관측이 이루어질 때 실제로 규명될 수 있다. 하지만, 수문 순환과 물수지 평가에 중요한 부분을 차지하는 증발산량의 경우 관측값보다 단순한 가정이나 경험식에 의한 추정값을 사용하고 있어 그 자료의 신뢰성에 대해서도 꾸준히 문제가 제기되어 왔다. 따라서, 수문 순환과 물수지의 정량적인 분석을 위해서는 수문 순환 과정에서 상당부분을 차지하는 증발산량의 측정(실측)과 자료의 축척이 필요한 실정이다. 본 연구는 국토교통부의 기초수문자료 구축사업의 일환으로 수행되고 있으며, 수문자료의 다양화 목적을 가지고 에디공분산 기술을 사용하여 증발산량을 직접 관측하고 있다. 관측지점은 한반도의 약 70%를 차지하는 산림지 중 대표적 식생 기능 형태인 혼효림으로 구성된 지점(설마천 관측소, 2007년 8월부터)과, 인위적인 관개가 이루어지는 논경지(청미천 관측소, 2008년 8월부터)에서의 증발산량 측정을 수행하였다. 그 결과 두 지점에서 증발산량의 계절 및 경년 변동 특성을 파악 할 수 있었다. 혼효림(설마천 관측소)에서 산정된 증발산량은 2008년 471.7mm, 2009년 408.4mm, 2010년 489.4mm, 2011년 387.0mm, 2012년 323.3mm, 2013년 293.3mm, 2014년 360.9mm, 2015년 419.6mm이고, 강수량 대비 증발산량은 18.9%~56.2%를 보였다. 논경지(청미천 관측소)에서 산정된 증발산량은 2009년 571.8mm, 2010년 650.6mm, 2011년 523.9mm, 2012년 509.8mm, 2013년 467.9mm 2014년 533.9mm, 2015년 600.5mm이고, 강수량 대비 증발산량은 25.6%~71.4%를 보였다. 강수량 대비 비율의 최대값은 설마천 관측소는 2014년, 청미천 관측소는 2015년에 발생하였다.. 평균 증발산량 비율은 산림지인 설마천 관측소보다 논경지인 청미천 관측소가 평균 15.5%정도 높게 나타났다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.2
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• pp.228-242
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• 2023

We examined the osteological development of the cranium, visceral skeleton, pectoral girdle, vertebral column, fins, and pterygiophore of small yellow croaker Larimichthys polyactis cultured at the Jeju Fisheries Research Institute. At 5.89 mm NL (notochord length), the larvae already had ossified frontal and basioccipital bones, parasphenoids, and vomer in the cranium. All elements of the visceral skeleton except the metapterygoid were ossified at 5.89 mm NL. Preorbital bone was ossified at 8.11 mm SL (standard length), and suborbital bones were ossified at 12.90 mm SL. In the vertebral column, ossification proceeded from the first to last centrum. The urostyle ossified at 7.41 mm SL. The caudal skeleton ossified at 6.78 mm NL, along with three hypural bones. In the pectoral girdle, the cleithrum, supracleithrum, postcleithrum, and post-temporal bones ossified at 5.89 mm NL. Caudal fin ossification began at 6.19 mm SL and was complete at 7.16 mm SL. Dorsal and anal fin ossification began at 7.16 mm SL and was complete at 8.62 mm and 8.11 mm SL, respectively. Anal and dorsal pterygiophore bone ossification was complete at 9.86 mm and 11.54 mm SL, respectively, and that of the supraneural bones was complete at 9.60 mm SL.

• Restorative Dentistry and Endodontics
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• v.46 no.3
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• pp.39.1-39.12
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• 2021

Objectives: This study analyzed the physical-chemical behavior of 2 bulk fill resin composites (BFCs; Filtek Bulk Fill [FBF], and Tetric-N-Ceram Bulk Fill [TBF]) used in 2- and 4-mm increments and compared them with a conventional resin composite (Filtek Z250). Materials and Methods: Flexural strength and elastic modulus were evaluated by using a 3-point bending test. Knoop hardness was measured at depth areas 0-1, 1-2, 2-3, and 3-4 mm. The translucency parameter was measured using an optical spectrophotometer. Real-time polymerization kinetics was analyzed using Fourier transform infrared spectroscopy. Results: Flexural strength was similar among the materials, while TBF showed lower elastic modulus (Z250: 6.6 ± 1.3, FBF: 6.4 ± 0.9, TBF: 4.3 ± 1.3). The hardness of Z250 was similar only between 0-1 mm and 1-2 mm. Both BFCs had similar hardness until 2-3 mm, and showed significant decreases at 3-4 mm (FBF: 33.45 ± 1.95 at 0-1 mm to 23.19 ± 4.32 at 3-4 mm, TBF: 23.17 ± 2.51 at 0-1 mm to 15.11 ± 1.94 at 3-4 mm). The BFCs showed higher translucency than Z250. The polymerization kinetics of all the materials were similar at 2-mm increments. At 4-mm, only TBF had a similar degree of conversion compared with 2 mm. Conclusions: The BFCs tested had similar performance compared to the conventional composite when used in up to 2-mm increments. When the increment was thicker, the BFCs were properly polymerized only up to 3 mm.

• Journal of the Korean Society of Radiology
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• v.14 no.3
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• pp.203-209
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• 2020

The purpose of this study is to assess the mechanical stability and alignment of the patient positioning system (PPS) of Leksell Gamma Knife Perfexion(LGK PFX). The alignment of the PPS of the LGK PFX was evaluated through measurements of the deviation of the coincidence of the Radiological Focus Point(RFP) and the PPS Calibration Center Point(CCP) applying different weights on the couch(0, 50, 60, 70, 80, and 90 kg). In measurements, a service diode test tool with three diode detectors being used biannually at the time of the routine preventive maintenance was used. The test conducted with varying weights on the PPS using the service diode test tool measured the radial deviations for all three collimators 4, 8, and 16 mm and also for three different positions of the PPS. In order to evaluate the alignment of the PPS, the radial deviations of the correspondence of the radiation focus and the LGK calibration center point of multiple beams were averaged using the calibrated service diode test tool at three university hospitals in Busan and Gyeongnam. Looking at the center diode for all collimators 4, 8, and 16 mm without weight on the PPS, and examining the short and long diodes for the 4 mm collimator, the means of the validation difference, i.e., the radial deviation for the setting of 4, 8, and 16 mm collimators for the center diode were respectively measured to 0.058 ± 0.023, 0.079 ± 0.023, and 0.097 ± 0.049 mm, and when the 4 mm collimator was applied to the center diode, the short diode, and the long diode, the average of the radial deviation was respectively 0.058 ± 0.023, 0.078 ± 0.01 and 0.070 ± 0.023 mm. The average of the radial deviations when irradiating 8 and 16 mm collimators on short and long diodes without weight are measured to 0.07 ± 0.003(8 mm sd), 0.153 ± 0.002 mm(16 mm sd) and 0.031 ± 0.014(8 mm ld), 0.175 ± 0.01 mm(16 mm ld) respectively. When various weights of 50 to 90 kg are placed on the PPS, the average of radial deviation when irradiated to the center diode for 4, 8, and 16 mm is 0.061 ± 0.041 to 0.075 ± 0.015, 0.023 ± 0.004 to 0.034 ± 0.003, and 0.158 ± 0.08 to 0.17 ± 0.043 mm, respectively. In addition, in the same situation, when the short diode for 4, 8, and 16 mm was irradiated, the averages of radial deviations were 0.063 ± 0.024 to 0.07 ± 0.017, 0.037 ± 0.006 to 0.059 ± 0.001, and 0.154 ± 0.03 to 0.165 ± 0.07 mm, respectively. In addition, when irradiated on long diode for 4, 8, and 16 mm, the averages of radial deviations were measured to be 0.102 ± 0.029 to 0.124 ± 0.036, 0.035 ± 0.004 to 0.054 ± 0.02, and 0.183 ± 0.092 to 0.202 ± 0.012 mm, respectively. It was confirmed that all the verification results performed were in accordance with the manufacturer's allowable deviation criteria. It was found that weight dependence was negligible as a result of measuring the alignment according to various weights placed on the PPS that mimics the actual treatment environment. In particular, no further adjustment or recalibration of the PPS was required during the verification. It has been confirmed that the verification test of the PPS according to various weights is suitable for normal Quality Assurance of LGK PFX.

• Radiation Oncology Journal
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• v.25 no.4
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• pp.268-277
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• 2007

Purpose: Respiratory motion is a considerable inhibiting factor for precise treatment with stereotactic radiosurgery using the CyberKnife (CK). In this study, we developed a moving phantom to simulate three-dimensional breathing movement and investigated the distortion of dose profiles between the use of a moving phantom and a static phantom. Materials and Methods: The phantom consisted of four pieces of polyethylene; two sheets of Gafchromic film were inserted for dosimetry. Treatment was planned to deliver 30 Gy to virtual tumors of 20, 30, 40, and 50 mm diameters using 104 beams and a single center mode. A specially designed robot produced three-dimensional motion in the right-left, anterior-posterior, and craniocaudal directions of 5, 10 and 20 mm, respectively. Using the optical density of the films as a function of dose, the dose profiles of both static and moving phantoms were measured. Results: The prescribed isodose to cover the virtual tumors on the static phantom were 80% for 20 mm, 84% for 30 mm, 83% for 40 mm and 80% for 50 mm tumors. However, to compensate for the respiratory motion, the minimum isodose levels to cover the moving target were 70% for the $30{\sim}50$ mm diameter tumors and 60% for a 20 mm tumor. For the 20 mm tumor, the gaps between the isodose curves for the static and moving phantoms were 3.2, 3.3, 3.5 and 1.1 mm for the cranial, caudal, right, and left direction, respectively. In the case of the 30 mm tumor, the gaps were 3.9, 4.2, 2.8, 0 mm, respectively. In the case of the 40 mm tumor, the gaps were 4.0, 4.8, 1.1, and 0 mm, respectively. In the case of the 50 mm diameter tumor, the gaps were 3.9, 3.9, 0 and 0 mm, respectively. Conclusion: For a tumor of a 20 mm diameter, the 80% isodose curve can be planned to cover the tumor; a 60% isodose curve will have to be chosen due to the tumor motion. The gap between these 80% and 60% curves is 5 mm. In tumors with diameters of 30, 40 and 50 mm, the whole tumor will be covered if an isodose curve of about 70% is selected, equivalent of placing a respiratory margin of below 5 mm. It was confirmed that during CK treatment for a moving tumor, the range of distortion produced by motion was less than the range of motion itself.

• Parasites, Hosts and Diseases
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• v.25 no.1
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• pp.83-84
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• 1987

1983년 10월에 15세된 여자가 내원 수일 전부터 오른쪽 눈의 이물감과 소양증을 주소로 내원하였다. 며칠전 환자 자신이 오른쪽 눈에서 충체를 꺼냈으며, 내원하여 2마리를 적출하였다. 두 마리는 모두 자충이었으며 각각 길이 13.4mm, 폭 0.36mm와 길이 8.3mm, 폭 0.39mm였으며 구강의 길이는 각각 0.24mm, 0.31mm이었다. 표피의 가로주름이 식도부위에서는 1mm당 281개, 중앙부위는 172개, 후단부는 162개이었으며 충체 전단부터 질 입구까지의 길이는 0.44mm이었다. 이상의 소견으로 두마리 충체를 Thelazia callipaeda로 동정하였다. 이 동양안충 감염에는 한국에서 15번째이다.

• Journal of radiological science and technology
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• v.31 no.3
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• pp.277-285
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• 2008

As a result of measuring the size of corpus callosum in normal Korean people by using MRI, the following conclusions were obtained. 1. Maximum, minimum, and mean values by the region in whole subjects 1) Anteroposterior length amounted to the mean with 69.30mm, the minimum with 50.70mm, and the maximum with 80.40mm. 2) Diameter of genu amounted to the mean with 11.93mm, the minimum with 6.00mm, and the maximum with 18.50mm. 3) Diameter of mid body amounted to the mean with 7.00mm, the minimum with 3.40mm, and the maximum with 10.40mm. 4) Diameter of narrowing portion amounted to the mean with 4.51mm, the minimum with 0.80mm, and the maximum with 9.50mm. 5) Diameter of splenium amounted to the mean with 12.17mm, the minimum with 6.90mm, and the maximum with 17.20mm. 2. Comparison by region according to the gender in the whole subjects 1) Anteroposterior length was bigger in men than in women, and showed the significant difference depending on gender. 2) Diameter of genu, diameter of mid body, and diameter of narrowing portion were bigger in men than in women, but there was no significant difference. 3) Diameter of splenium was bigger in men than in women, and showed the statistically significant difference. 3. Comparison by region according to the age in the whole subjects 1) Anteroposterior length was the biggest in the 50s at the age, and was smaller in heir 10s than other age levels. In addition, the significant difference was indicated depending on age. 2) Diameter of genu and diameter of mid body were the biggest in their 30s, and were smaller in the 60s than other age levels. And, the statistically significant difference was indicated. 3) Diameter of narrowing portion was the thickest in their 20s, and was thinner in their 60s than other age levels. And, the significant difference was indicated depending on age. 4) Diameter of splenium was the thickest in their 30s, and was thinner in their 10s than other age levels. And, the statistically significant difference was indicated. 4. Correlation by region in whole subjects 1) Diameter of genu showed the statistically significant positive correlation with anteroposterior length. 2) Diameter of mid body showed the statistically significant positive correlation with anteroposterior length and diameter of genu. 3) Diameter of narrowing portion didn't show the statistically significant correlation with anteroposterior length, but showed the statistically significant positive correlation with diameter of genu and diameter of mid body. 4) Diameter of splenium showed the statistically significant positive correlation with anteroposterior length, diameter of genu, diameter of mid body, and diameter of narrowing portion.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.27 no.3
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• pp.193-203
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• 2001

Orthognathic surgery of the mandibular prognathism and the retrognathism is tend to be performed on the mandibular ramus to prevent inferor alveolar nerve injuries. The purpose of this study is to find a safe and accurate reference point on mandibular ramus for orthognathic surgery by comparative anatomical study of dentofacial deformity patients. We use 38 Korean Cadavers with normal occlusion(Group 1), 3-dimensional simulation of computerized tomogram of 23 patients with retrognathism (Group 2), 27 patients with mandibular prognathism (Group 3). Following results are obtained : 1. The maximum thickness of the mandibular ramus is $8.78{\pm}1.15mm$ for Group 2, $7.61{\pm}1.26mm$ for Group 1, $6.95{\pm}0.82mm$ for Group3 respectively (P=0001). The minimum thickness is $5.51{\pm}1.08mm$ for Group 1, $5.06{\pm}0.40mm$ for Group 2, $4.56{\pm}0.78mm$ for Group3, respectively (p=0.0001). But, the thickness at the level of 5mm above the lingular is $0.78{\pm}0.65mm$ for Group 2, $5.63{\pm}1.28mm$ for Group 1, $5.32{\pm}0.91mm$ for Group 3, respectively. There is no significant difference between these groups(P=0.0510). 2. The horizontal location from the midwaist point to lingular is $0.18{\pm}1.57mm$ for Group 1, $0.69{\pm}1.33mm$ for Group 2, $0.66{\pm}1.66mm$ for Group 3, and there is no significant difference between these groups(p=0.0835). But the vertical location from the midwaist point to lingular is $1.45{\pm}2.64mm$ for Group 1, $0.63{\pm}1.44mm$ for Group 2, $0.34{\pm}1.81mm$ for Group 3, and there is significant difference between these groups(p=0.0030). 3. The horizontal location from the midwaist point to mandibular foramen is $0.29{\pm}1.75mm$ for Group 1, $0.63{\pm}1.44mm$ for Group 2, $0.34{\pm}1.81mm$ for Group 3, and there is no significant difference between these groups(p=0.5403). But the vertical location from the midwaist point to mandibular foramen is $-3.33{\pm}4.43mm$ for Group1, $-4.79{\pm}2.26mm$ for Group 2, $-6.06{\pm}2.99mm$ for Group 3, and there is significant difference between these groups(P=0.0001). 4. The horizontal length from the disto-buccal cusp tip of mandibular second molar to lingula is $30.97{\pm}4.17mm$ for Group 3, $28.29{\pm}2.65mm$ for Group 1, $25.48{\pm}0.77mm$ for Group 2 (p=0.0000), and also vertical length is $7.72{\pm}3.22mm$ for Group 3, $6.38{\pm}1.83mm$ for Group 1, $5.89{\pm}2.30mm$ for Group 2 (P=0.0014). 5. The location of lingular is 0.50 from anterior border of mandibular ramus in all groups, if it assumed the length from anterior border to posterior border is 1. And it is almost 0.33 from the sigmoid notch, if it assumed the length from sigmoid notch to antegonial notch is 1. 6. In Group 1, Antilingular prominence is located on ($1.12{\pm}1.43mm,\;4.01{\pm}2.36mm$) from the midwaist point, and there is no correlation between antilingular prominence and lingular, mandibular foramen.

• The Journal of Korean Academy of Prosthodontics
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• v.23 no.1
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• pp.39-59
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• 1985

The purpose of this study was to investigate how gap distances of 0.13mm, 0.15mm, 0.20mm, and 0.30mm affects solder joint strength from gold alloys and nickel-chromium base alloys and to examine the composition of solder gold, the solder joint of gold alloys and nickel-chromium base alloys. The tensile test specimens were prepared in the split stainless steel mold with a half dumbbell shape 2.5mm in diameter and l2mm in length. 6 pairs of specimens of each gap distance group of gold alloys and nickel-chromium base alloys were made and 48 pairs of all specimens were soldered with solder gold of 666 fineness. All soldered specimens were machined to a uniform diameter and then a tensile load was applied at a cross-head speed of 0.10mm/min using Instron Universal Testing Machine, Model 1115. The fractured specimens at solder gold of solder joint fracture with each gap distance of 0.13mm, 0.15mm, 0.20mm, and 0.30mm were examined under the Scanning Electron Microscope, JSM-35c and the composition of solder gold, the solder joint of gold alloys and nickel-chromium base alloys was analyzed by Electron Probe Micro Analyzer. The results of this study were obtained as follows: 1. In case of soldering of gold alloys, the tensile strength between gold alloys showed $37.33{\pm}2.52kg/mm^2$ at 0.13, $39.14{\pm}3.35kg/mm^2$ at 0.15mm, $43.76{\pm}2.97kg/mm^2$ at 0.20mm, and $49.18{\pm}4.60kg/mm^2$ at 0.30mm. There was statistically significant difference at each gap distance, and so the greater increase of gap distance showed the greater tensile strength. 2. In case of soldering of nickel-chromium base alloys, the tensile strength between nickel-chromium base alloys showed $34.84{\pm}4.26kg/mm^2$ at 0.13mm, $37.25{\pm}2.49kg/mm^2$ at 0.15mm, $42.91{\pm}4.32kg/mm^2$ at 0.20mm, and $46.93{\pm}4.21kg/mm^2$ at 0.30mm. There was not statistically significant difference only between 0.13mm and 0.15mm and bet ween 0.20 mm and 0.30mm, but generally the greater increase of gap distance showed the greater tensile strength. 3. The greater increase of gap distance shoed less porosities in solder gold at solder joint fracture. 4. In solder gold Au, Cu, Ag, Zn, and Sn were composed and Au and Cu were mostly distributed uniformly. 5. In solder joints of solder gold and gold alloys Au, Cu, Ag, Zn, and Sn were composed in solder gold and Au, Cu, Ag, Pt, and Pd were composed in gold alloys. Au and Cu of solder gold and gold alloys were mostly distributed uniformly and the diffusion of other elements except Pt and Pd around the solder joint was not almost found. In solder joints of solder gold and nickel-chromium base alloys Au, Cu, Ag, Zn, and Sn were composed in solder gold and Ni, Cr, and Al were composed in nickel-chromium base alloys. Au and Cu of solder gold and Ni and Cr of nickel-chromium base alloys were mostly distributed uniformly and the diffusion of other elements except Cr around the solder joint was not almost found.

• Radiation Oncology Journal
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• v.24 no.3
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• pp.192-200
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• 2006

[ $\underline{Purpose}$ ]: To evaluate the movement of surgical clips implanted in breast tumor bed during normal breathing. $\underline{Materials\;and\;Methods}$: Seven patients receiving breast post-operative radiotherapy were selected for this study. Each patient was simulated in a common treatment position. Fluoroscopic images were recorded every 0.033 s, 30 frames per 1 second, for 10 seconds in anterior to posterior (AP), lateral, and tangential direction except one patient's images which were recorded as a rate of 15 frames per second. The movement of surgical clips was recorded and measured, thereby calculated maximal displacement of each clip in AP, lateral, tangential, and superior to inferior (SI) direction. For the comparison, we also measured the movement of diaphragm in SI direction. $\underline{Results}$: From AP direction's images, average movement of surgical clips in lateral and SI direction was $0.8{\pm}0.5\;mm$ and $0.9{\pm}0.2\;mm$ and maximal movement was 1.9 mm and 1.2 mm. Surgical clips in lateral direction's images were averagely moved $1.3{\pm}0.7\;mm$ and $1.3{\pm}0.5\;mm$ in AP and SI direction with 2.6 mm and 2.6 mm maximal movement in each direction. In tangential direction's images, average movement of surgical clips and maximal movement was $1.2{\pm}0.5\;mm$ and 2.4 mm in tangential direction and $0.9{\pm}0.4\;mm$ and 1.7 mm in SI direction. Diaphragm was averagely moved $14.0{\pm}2.4\;mm$ and 18.8 mm maximally in SI direction. $\underline{Conclusion}$: The movement of clips caused by breathing was not as significant as the movement of diaphragm. And all surgical clip movements were within 3 mm in all directions. These results suggest that for breast radiotherapy, it may not necessary to use breath-holding technique or devices to control breath.