• Journal of the Korean Vacuum Society
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• v.19 no.3
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• pp.230-235
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• 2010

In this paper, we controlled the deposition rate and reflective index with process conditions that are TCP power, gas flow ratio and bias for optical properties of $SiO_2$ thin film using TCP-CVD equipment. We obtained a excellent $SiO_2$ thin film which has a excellent uniformity (<1 [%]), deposition rate (0.28 [${\mu}m$/ min]) and reflective index (1.4610-1.4621) within 4" wafer with process conditions ($SiH_4:O_2$=50 : 100 [sccm], TCP power 1 [kW], bias 200 [W]) at [$300^{\circ}C$].

• International Journal of Contents
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• v.13 no.4
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• pp.12-15
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• 2017

Among the possible stereotactic body radiation therapy (SBRT) modalities used to treat patients with metastatic spinal tumors, this study compared Cyberknife, tomotherapy, and volumetric modulated arc radiotherapy (VMAT). We established treatment plans for each of them modality and quantitatively analyzed the dose evaluation factors of the dose-volume histogram (DVH) for all spinal bones, focusing on the tumor and spinal cord, in order to examine the usefulness of VMAT. For the treatment planning dose, the mean dose ($D_{max}$) and $D_{5%}$ showed statistical differences in the target dose, but no difference was shown in the spinal cord dose. For the DVH indices, tomotherapy showed the best performance was the best in terms of uniformity index, while VMAT showed better performance was better than the other two modalities in terms of the conformity index and the dose gradient index. VMAT had a much shorter treatment time than Cyberknife and tomotherapy. These findings suggest that VMAT FFF is the most effective therapy for SBRT of patients with metastatic spinal tumors for whom a high dose of radiation is prescribed.

• Progress in Medical Physics
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• v.25 no.4
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• pp.199-204
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• 2014

The purpose of this study is to evaluate the dosimetric outcome of the field-in-field (FIF) plans compared with tangential wedged beams (TWB) plans for whole breast irradiation of breast cancer patients. Twenty patients with right-sided breast cancer and 10 patients with left-sided breast cancer were retrospectively enrolled in this study. We generated a FIF plan and a TWB plan for each patient to compare dosimetric outcomes. The dose the homogeneity index (HI), the conformity index (CI) and the uniformity index (UI) were defined and used for comparison of the dosimetric outcome of the planning target volume (PTV). To compare the dosimetric outcome of the organs at risk, the mean dose ($D_{mean}$) and the percentage of volumes receiving more than 10, 20 and 30 Gy of the ipsilateral lung and heart were used. The FIF plans had significantly lower HI (p=0.002), higher UI (p=0.000) and CI (p=0.000) than those of the TWB plans, which means that the FIF plans were better than the TWB plans in the dosimetric comparisons of the PTV. The $V10_{lung}$ ($17.1{\pm}7.1$ vs. $18.6{\pm}6.6%$, p=0.020) and $V30_{lung}$ ($10.3{\pm}5.1%$ vs. $10.7{\pm}5.2%$, p=0.000) were lower with the FIF plans compared with those of the TWB plans, with statistical significance. For the left-sided breast cancer patients, $D_{mean}$ of the heart ($2.6{\pm}1.3$ vs. $3.2{\pm}1.4$ Gy, p=0.000), $V20_{heart}$ ($3.4{\pm}2.6$ vs. $3.6{\pm}2.8%$, p=0.005) and $V30_{heart}$ ($2.6{\pm}2.3%$ vs. $2.9{\pm}2.4%$, p=0.004) were significantly lower for the FIF plans in comparison with those of the TWB plans. The FIF plans increased the dose homogeneity, conformity and uniformity of the target volume for the whole-breast irradiation compared with the TWB plans. Moreover, FIF plans reduced the doses to the ipsilateral lung and heart.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.6 s.97
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• pp.622-631
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• 2005

In this paper, we reduce 'over and under deviation' and 'over and under testing' which have a cause of uncertainty in electromagnetic radiated immunity test. We analyze continued measurement method of field uniformity and propose new estimate method having the minimum uncertainty condition. We test comparison in 4 anechoic chambers and analyze FDI(Field Deviation Index) which is the minimum deviation excess 6 dB on fields. We obtain that the proposed test method improve 1.193 dB than domestic standard(KN 61000-4-3) and 0.017 dB than international standard (IEC61000-4-3) in every frequency. In the test result 'over and under testing point' have 926 point at every field area and have 118 point at center uniform area. These result know that proposed measurement method have 10 point less at every field area and 9 point less at center uniform area than continued measurement method. The proposed test method have few point more than continued measurement method. Therefore, we confirmed that the proposed test method have the minimum uncertainty in electromagnetic radiated immunity test.

• Journal of The Korean Society of Agricultural Engineers
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• v.64 no.6
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• pp.65-75
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• 2022

Livestock industry in Korea has been growing rapidly and has reached 23 trillion Korean won in 2021. This study focuses on broiler, which is one of the largest sectors in livestock industry. As the effects of climate change get more serious, primary industry such as livestock industry is fragile to climate change since it directly interacts with nature. Therefore, maintaining suitable rearing environment is important. One of the most frequently used ventilation type for controlling the rearing environment of broiler house, tunnel ventilation, causes frequent air velocity fluctuation which makes maintaining the rearing environment important. By measuring the air temperature, relative humidity and air velocity in various points inside the broiler house, the internal thermal environment uniformity was analyzed according to length, width and zone. The experimental house was found to have dead zone with high air temperature, relative humidity and low air velocity near the end of the inlet and at the end of the broiler house. By using heat stress index to analyze quantitatively, zone with highest heat stress index was found to increase by 7.55% compared to the lowest zone. As a result, to maintain uniform rearing environment inside the broiler house, different factors must be measured and analyzed and used to operate the environmental control facilities.

• Journal of the Korean Society of Radiology
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• v.9 no.5
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• pp.287-293
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• 2015

Because of esophageal cancer has the long length of the lesion and also inhomogeneous in depth. So, the radiation dose distribution was inhomogeneous in radiation therapy. To overcomes the dose distribution uniformity using half beam method. Patient's CT image was used radiation treatment planning. We used two planning methods that one is the using normal beam and another is using half beam. Than comparing the two radiotherapy planning using target coverage, dose volume histogram, conformity index, homogeneity index and normal tissues - heart, spinal cord, lung -. In results, Treatment planning using half beam is little more than normal beam in target coverage, dose volume histogram, conformity index, homogeneity index and normal tissues covering. However, If the patient is not correct position patients may arise a side effect. Thus, the using in Half beam involving the geometrically exact under lung cancer is considered to advantage.

• Korean Journal of Optics and Photonics
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• v.22 no.1
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• pp.5-9
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• 2011

There are technical difficulties in measuring the numerical apertures of multi-mode gradient-index plastic optical fibers (GI-POFs) due to their strong speckle noise originating from dopants, non-uniformity of gradient-index profile, and multi-mode interference. Therefore, we propose a new method of obtaining the numerical aperture by controlling the size of the incident laser beam and measuring the numerical aperture of GI-POF. The results show that we can get a value for the numerical aperture of GI-POF very similar to that measured by the conventional method. We can also obtain the optimum launching condition of input beam and maximum coupling efficiency.

• Progress in Medical Physics
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• v.17 no.1
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• pp.6-16
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• 2006

The goal of this study was to develop new indices for effectively evaluating the dose coverage and homogeneity based on the target-volume dose-volume histogram (TV-DVH) of intensity-modulated radio-therapy treatment plans. A new coverage Index and a new homogeneity index were developed by integrating a modified TV-DVH and by fitting a TV-DVH with a modified step function, respectively. The coverage index, named the l-index, indicates whether the dose coverage for the target volume is adequate based on user-defined criteria. A lower l-index indicates higher dose coverage of the tumor volume. The index for assessing dose homogeneity in a target volume, named the n-index, is more accurate than the conventional method in evaluating the dose homogeneity in a tumor volume. The baseline treatment plan for a target volume coverage and homogeneity is discussed. The proposed simple indices have been demonstrated to be effective in evaluating the dose coverage and homogeneity for TV-DVHs.

• The Plant Pathology Journal
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• v.21 no.2
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• pp.137-141
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• 2005

The effect of cotton leaf mosaic disease on morphology, yield and fibre characteristics was examined for a susceptible cotton candidate variety CRIS-168. Plants inoculated at most susceptible growth stage (six week) under screen house showed severe mosaic symptoms. There was a significant reduction in plant height and yield. Cotton leaf mosaic disease was found to produce severe effects on plant morphology with 24.1% reduction in plant height, 25% in internode length and 37.5% in number of sympodia on main stem. However no changes were observed against number of monopodial branches per plant. Inoculated plants showed 82% decrease in yield/plant, 80% in number of boll set/ plant, 12.1% in boll weight, 12.8% in lint weight, 10.8% in seed weight, and 6.8% in seed index. Cotton leaf mosaic disease also showed effects on fibre characteristics with 0.8% decrease in GOT and 1.6% in fibre length. In contrast, uniformity ratio, fibre fineness and maturity index was increased by 20.5%, 14.4% and 0.9%, respectively.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.43 no.3
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• pp.176-182
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• 2007

Fishing power, which means performance of fishing vessel or catchability of fishing gear, can explain using by fishing power index(FPI) to compare fishery efficiency among uniformity types of fishery that work during the fixed period in specific fishing ground. This research analyzed on their fishing power and catchability using comparing each sampled vessels of coastal trap fishery for common octopus. The results showed that they were no difference in amount of used trap and immersed time etc. in CPUE among sampled vessels, and had no correlation of catch production due to vessel's tonnage. Most vessel's FPI estimates but 3 vessels were higher than the averaged, and showed similar fishing power in general. And then, CPUE and FPI showed that 4 to 5 tonnage vessels would be superior to another, 4 tonnage vessels had also good catchability. Therefore, we estimated that 4 tonnage vessels had the most efficiency work for coastal trap fishery for common octopus.