• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.241.2-241.2
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• 2013

최근, 비정질 산화물 반도체 thin film transistor (TFT)는 수소화된 비정질 실리콘 TFT와 비교하여 높은 이동도와 큰 on/off 전류비, 낮은 구동 전압을 가짐으로써 빠른 속도가 요구되는 차세대 투명 디스플레이의 TFT로 많은 연구가 진행되고 있다. 한편, 기존의 MOSFET 제작 시 우수한 박막을 얻기 위해서는 $500^{\circ}C$ 이상의 높은 열처리 온도가 필수적이며 이는 유리 기판과 플라스틱 기판에 적용하는 것이 적합하지 않고 높은 온도에서 수 시간 동안 열처리를 수행해야 하므로 공정 시간 및 비용이 증가하게 된다는 단점이 있다. 따라서, 본 연구에서는 RF sputter를 이용하여 증착된 비정질 InGaZnO pesudo MOSFET 소자를 제작하였으며, thermal 열처리와 microwave 열처리 방식에 따른 전기적 특성을 비교 및 분석하고 각 열처리 방식의 열처리 온도 및 조건을 최적화하였다. P-type bulk silicon 위에 산화막이 100 nm 형성된 기판에 RF 스퍼터링을 이용하여 InGaZnO 분말을 각각 1:1:2mol% 조성비로 혼합하여 소결한 타겟을 사용하여 70 nm 두께의 InGaZnO를 증착하였다. 연속해서 Photolithography 공정과 BOE(30:1) 습식 식각 과정을 이용해 활성화 영역을 형성하여 소자를 제작하였다. 제작 된 소자는 pseudo MOSFET 구조이며, 프로브 탐침을 증착 된 채널층 표면에 직접 접촉시켜 소스와 드레인 역할을 대체하여 동작시킬 수 있어 전기적 특성을 간단하고 간략화된 공정과정으로 분석할 수 있는 장점이 있다. 열처리 조건으로는 thermal 열처리의 경우, furnace를 이용하여 각각 $300^{\circ}C$, $400^{\circ}C$, $500^{\circ}C$, $600^{\circ}C$에서 30분 동안 N2 가스 분위기에서 열처리를 실시하였고, microwave 열처리는 microwave를 이용하여 각각 400 W, 600 W, 800 W, 1000 W로 20분 동안 실시하였다. 그 결과, furnace를 이용하여 열처리한 소자와 비교하여 microwave 를 통해 열처리한 소자에서 subthreshold swing (SS), threshold voltage (Vth), mobility 등이 개선되는 것을 확인하였다. 따라서, microwave 열처리 공정은 향후 저온 공정을 요구하는 MOSFET 제작 시의 훌륭한 대안으로 사용 될 것으로 기대된다.

• Journal of Environmental Impact Assessment
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• v.33 no.2
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• pp.84-98
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• 2024

This study proposed a prediction equation for the estimation of blasting vibaration and blasting noise, utilizing 320 datasets for the blasting vibration and blasting noise acquired during urban blasting works in the Incheon, Suwon, Wonju, and Yangsan regions. The proposed blasting vibration prediction equation, derived from regression analysis, indicated correlation coefficients of 0.879 and 0.890 for SRSD and CRSD, respectively, with an R² value exceeding 0.7. In the case of the blasting noise prediction equation, stepwise regression analysis yielded a correlation coefficient of 0.911 between the prediction values and real measurements for the blasting nosie, and further analysis to determine the constant value revealed a correlation coefficient of 0.881, with an R² value also exceeding 0.7. These results suggest the feasibility of applying the proposed prediction equations when environmental impact assessments or education environment evaluation according to urban development or apartment construction projects is performed.

• Korean Journal of Environment and Ecology
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• v.28 no.3
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• pp.273-280
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• 2014

This study examined whether Dybowski's brown frogs(Rana dybowskii) in noisy highway roadsides had different mating calls from those in natural sites. We selected four study sites: two rice paddy sites in Youngdong Highway roadside and two nearby natural counterparts. Frog calls were recorded between 18:30 and 20:00 on February 24, February 27, and March 14, 2014. Frog calls in the natural sites had fundamental frequency approximately at 700 Hz with two to four apparent harmonics, while frog calls in the highway sites had higher fundamental frequency with up to seven apparent harmonics. Analysis of variance (ANOVA) shows that a roadside site that are directly exposed to highway noise had statistically higher frog calling frequency than other study sites. However, the higher calling frequency was not found in another roadside site that differed in elevation from the highway and was buffered by forests. These results indicate that male frogs in a noisy highway roadside called females with a higher pitch and more apparent harmonics to avoid being masked by highway noise. These results also suggest that there is a threshold noise level that interrupts frog's mating behavior and it is needed to maintain highway roadside noise to this threshold level.

• Korean Journal of Remote Sensing
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• v.32 no.3
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• pp.201-220
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• 2016

In this study, the net solar radiation fluxes at the surface are retrieved by updating an existing algorithm to be applicable for MODerate resolution Imaging Spectroradiometer (MODIS) observations, in which linear relationships between the solar radiation reflected from the top of atmosphere and the net surface solar radiation are employed. The results of this study have been evaluated through intercomparison with existing Clouds and the Earth's Radiant Energy System (CERES) data products and ground-based data from pyranometers at Gangneung-Wonju National University (GWNU) and the Southern Great Plains (SGP) of observatory of Atmospheric Radiation Measurement (ARM) site. Prior to the comparison of the surface radiation energy in relation to the energy balance of the earth, the radiation energy of the upper part of the atmosphere was compared. As a result, the coefficient of determination was over 0.9, showing considerable similarity, but the Root-Mean-Square-Deviation (RMSD) value was somewhat different, and the downward and net solar-radiation energy also showed similar results. The surface solar radiation data measured from pyranometers at Gangneung-Wonju National University (GWNU) and Atmospheric Radiation Measurement (ARM) observatory are used to validate the solar radiation data produced in this study. When compared to the GWNU, The results of this study show smaller RMSD values than CERES data, showing slightly better agreements with the surface data. On the other hand, when compared with the data from ARM SGP observatory, the results of this study bear slightly larger RMSD values than those for CERES. The downward and net solar radiation estimated by the algorithm of this study at a high spatial resolution are expected to be very useful in the near future after refinements on the identified problems, especially for those area without ground measurements of solar radiation.

• Korean Journal of Remote Sensing
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• v.36 no.5_1
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• pp.835-846
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• 2020

Recent severe climate changes and extreme weather events have caused the uncommon types of forest ecosystem disturbances such as hails and gypsy moths. This paper describes the analysis of the forest ecosystem disturbances using ISODATA (Iterative Self-organizing Data Analysis Technique Algorithm) with the RapidEye and Sentinel-2 images, regarding the cases of the hail damages in Hwasun in 2017 and the gypsy moth damages in the Chiak Mountain in 2020. In the case of hail damages, the comparison of the June image of this study and the July field survey of the previous study showed that the damage severity increased from June to July as the drought overlapped after the trees were injured by the hails. In the case of gypsy moths, significant leaf damages were found from the image of June, and the damages were mainly distributed at the low-altitude slope near Wonju City. We made sure that satellite remote sensing is a very effective method to detect various and unusual forest ecosystem disturbances caused by climate change. Also, it is expected that the Korean Medium Satellite for Agriculture and Forestry scheduled to launch in 2024 can be actively utilized to monitor such forest ecosystem disturbances.

• Parasites, Hosts and Diseases
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• v.23 no.1
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• pp.33-40
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• 1985

Two cases of human Erhinostoma hortense infection and their probable infection source were identified by prasiqantel (Distocide) treatment of the patients and by examining two kinds of fresh water fish which were eaten raw by them. The result of the research can be summarized as follows: 1. The patients, each aged 31 and 30, were residing in the same house in Wonju City, Kangwon Province. The first case was hospitalized due to epidemic hemorrhagic fever (E.H. fever) and the second case was healthy but had slight degree of abdominal pain and diarrhea from time to time. In the stool examination, eggs of 5. hortense ($114.3{\times}71.0{\mu\textrm{m}}$) average from the first case and $119.1{\times}68.3{\mu\textrm{m}}$ average from the second) were found. By administering single dose of praziquantel (10~15mg/kg) and purgation with magnesium salt to them. sin adults of 5. hortense were collected from the diarrheal stools of the second case. 2. By examining 8:k Moroco oxycephalus and 20 Carassius carassius which were captured at the place where the two patients had captured and eaten the fresh water fish, the metacercariae of Echinostoma sp. were found from 3 (3.5%) M. oxycephalus. 3. After the experimental infection of 3 isolated metacercariae to one albino rat three adults of 5. hortense were recovered. By the present study, the two patients revealing the echinostomatid eggs in their stools were proven to be infected with 5. hortense and to be the second and third human cases of this luke infection in Korea. Mcroco oxycephalus harboured the metacercariae of E. hortense and appeared to be a new second intermediate host.

• Pediatric Infection and Vaccine
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• v.21 no.1
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• pp.1-8
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• 2014

Purpose: The aim for this study was to investigate clinical manifestation of seasonal influenza A and B during the 2012 winter season in Wonju, South Korea. Their clinical and laboratorial characteristics and effect of oseltamivir were compared and analyzed. Methods: Children under the age of 18 years who visited the Wonju Severance Christian Hospital with fever or acute respiratory symptoms and who were diagnosed with influenza A or B by rapid antigen test from nasopharyngeal swab were selected for the study. The medical records of patients were retrospectively reviewed. Results: Influenza A was detected in 374 patients (83.7%), and influenza B in 72 (16.6%). The incidence of influenza A was highest in February (n=186), while that of influenza B was highest in March (n=36). The most common symptoms were fever (n=434, 97.1%) and cough (n=362, 81.0%). No significant differences were observed between influenza A and B in symptoms and laboratory data. Patients who had used oseltamivir within 2 days showed statistically lower admission rate, shorter admission duration, and lower incidence of pneumonia. Conclusion: This study found no statistical difference between influenza A and B, in symptoms, progression, and laboratory test, but those who were treated with oseltamivir given within 2 days of the onset of fever experienced more positive outcomes.

• Journal of Sericultural and Entomological Science
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• v.50 no.1
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• pp.10-14
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• 2012

Resveratrol is naturally occurring phytoalexin compounds produced by grape berries, peanuts, pine tree, mulberry fruits and their products in response to stress such as fungal infection, heavy metal ions or UV irradiation. The objective of this study was to determine resveratrol contents in wild-type mulberry leaves (Morus alba L., M. bombycis Koidz, and M. Lhou (Ser.) Koidz) collected from Won-ju, In-je and Yang-yang regions, Gangwon province, Korea. Resveratrol contents in wild-type mulberry leaves were higher in Autumn's than in Spring's, and higher than 16 cultivar's. Among the samples, 'No. 3', collected from Won-ju region and 'No. 7' collected from In-je showed high resveratrol contents of 539 and $491{\mu}g$/100 g DW (dry weight; DW), respectively, through the collection time. Therefore, two mulberry trees might be promising as potent resources for mulberry breeding and functional material development.

• Archives of design research
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• v.20
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• pp.199-208
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• 1997

The emphasis of simplicity in design is because of the desire to deliver much content with a simplest way. Since in general, a simple form is outstanding in its symbolical nature and the relief of plastic beauty is easy by it, it is usually applied to a form of a symbol mark. However, in the meantime, if any local autonomous group or enterprise which has not tried to give efforts to its advertisement than they might expect and might be disadvantageous in competition. For consumers, when they experienced several, forms of simple, symbol mark, would not remember the special features of each mark. Rather, for the psychology of perception, they might remember only the formative, common features, there by grouping the marks by their common features. In this study, some symbol marks in Dobong-gu Ward Office and Wonju city were inspected, reviewed, and analized. And its is a finding that the subjects of this study could not distinguish or identify any of marks from another mark having a similar image of it: the reason is that the simplicity of a symbol mark made or allowed them to recognize it identical with the other imaged: it proves that the mistakes, defects of memory, and accumulated errors are oriented to the identical image. After all, the appearented image and perceived image are differnt. Any of symbolmarks which takes a simple form does not mean the perceived image is also simple. As a final conclusion, designers, in order to produce any of competitive symbolmarks, need to thoroughly understand psychology of gestalt.

• Journal of Korean Ophthalmic Optics Society
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• v.15 no.3
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• pp.281-286
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• 2010

Purpose: This research provided basic data for refraction by comparing the corrected diopter of trial lens and phoropter. Methods: We compared the corrected diopter of trial lens and phoropter, and analyzed statistical significance and relations of the spherical lens corrected diopter and cylindrical lens corrected diopter according to the types (trial lens and phoropter) of subjective refractive instruments. Also we analyzed statistical significance and relations between cylindrical lens corrected diopter at the astigmatism and the types (trial lens and phoropter) of subjective refractory instruments. Results: When we measured the corrected diopter of simple myopia, the mean value for corrected diopter was S-2.74D using the trial lens and S-2.65D using the phoropter. So the corrected diopter was 0.09D smaller when measured by phoropter. The degree of astigmatism was measured C-0.81D using the trial lens and C-0.77D using the phoropter which showed that the measured value was 0.04D smaller using the phoropter. On correlation analysis between the refractive instruments (trial lens and phoropter) and the corrected diopter, there was significant (p<0.01) strong correlation between refractory machine and corrected spherical diopter (r=0.996) and the correlation between refractory machine and corrected cylindrical diopter was r=0.986 and was also significant (p<0.01). Conclusions: The use of phoropter than trial lens was more desirable when performing refraction on high myopia (simple refractive error, high astigmatism), and when using trial lens, you should consider the vertex distance and the gap between overlapped lenses before prescription.