• 한국농공학회지
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• 제34권E호
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• pp.1-11
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• 1992

Increasing national concern on nonpoint source pollution of surface and ground water Systems has led researchers and policy makers to develop certain agricultural Best Management Practices. As an initial step of broad study program above mentioned, this study reflected the effects of different tillage practice on bulk density and degree of saturation on two regional soils, namely Tama silt loam and Catlin silt loam. Results may help to clarify some of the conflicting findings on the impact of tillage systems on these parameters and it may also explain some of the reasons for specific role that different tillage systems play regarding nonpoint source pollution from agricultural fields.

• 한국초전도ㆍ저온공학회논문지
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• 제9권3호
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• pp.1-4
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• 2007

The current profiles in a coated conductor with transport current were calculated using an iterative inversion method from the data of the magnetic flux density profiles measured. The applied current was increased from 0 to 60 A by 10A step and decreased down to -60A by 20A step. The magnetic flux profiles were measured at a distance of 400 mm above the surface of the coated conductor using a scanning hall probe method. The current profiles calculated were very different from the Bean model: current density profile is not a constant in the critical region. However the aspect of the change of the current and magnetic flux density profiles in the case of decreasing applied current are similar to the theoretical calculations in Brandt's paper.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제49권4호
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• pp.203-209
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• 2000

This paper proposes the improvement of the etch rate of GaN using a magnetized inductively coupled $CH_4/H_2/Ar$plasma. The gradient magnetic field with the axial direction is investigated using Gauss-meter and the ion current density is measured using double Langmuir probe. The applied magnetic field changes the ion current density profile in the radial direction, resulting in producing the higher density in the outer region than in the center. GaN dry etching process is carried out based on the measurements of the ion current density. The each rate of 2000 /min is achieved with $CH_4/H_2/Ar$ chemistries at 800 W input power, 250W rf bias power, 10 mTorr pressure and 100 gauss magnetic field.

• 대한원격탐사학회지
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• 제34권2_1호
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• pp.191-201
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• 2018

본 연구에서는 한반도 서울의 연세대학교에서 Multi-Axis Differential Optical Absorption Spectroscopy(MAX-DOAS)장비로부터 산출된 원시자료를 이용하여 처음으로 최적추정(Optimal Estimation; OE)을 사용하여 오존전량 및 오존의 대류권 프로파일을 산출하였다. 오존전량 및 오존의 대류권 프로파일을 산출하기 위하여 최적추정을 통하여 MAX-DOAS자료의 광학두께 피팅을 수행하였다. 광학두께 피팅은 MAX-DOAS 장비로부터 각각의 기기 고도각별로 관측된 값을 천정각에서 관측된 값으로 나누어 계산된 자료를 통하여 수행하였다. 오존전량은 2017년 5월 23일 오전(08:13)과 오후(17:55)에 각각 375.4와 412.6 DU로 산출되었다. 오존의 대류권 프로파일(<10 km)은참값 오존존데와 비교하여 약 5% 이내의 오차로 산출되었다. 하지만 10 km 이상의 높은 고도에서는 산출 에러가 커져 10% 이상 과대추정 하는 것으로 산출되었다. MAX-DOAS 자료의 스펙트럼 피팅에 의한 오차는 오전과 오후에 각각 16.8%와 19.1%로 계산되었다. 본 연구에서 제시한 방법은 지상관측 기반의 초분광 UV 센서를 이용하여 오존전량과 대류권 오존 프로파일을 산출하는데 유용하게 사용될 수 있다.

• Mycobiology
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• 제39권4호
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• pp.283-289
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• 2011

The wild edible mushroom, Lentinus lepideus has recently been cultivated for commercial use in Korea. While the mushroom has been widely used for nutritional and medicinal purposes, the possible anti-hyperlipidemic action is unclear. The effects of dietary L. lepideus on plasma and feces biochemical and on the liver histological status were investigated in hypercholesterolemic rats. Six-wk-old female Sprague-Dawley albino rats were divided into three groups of 10 rats each. Biochemical and histological examinations were performed. A diet containing 5% L. lepideus fruiting bodies reduced plasma total cholesterol, triglyceride, low-density lipoprotein, total lipid, phospholipids, and the ratio of low-density to high-density lipoprotein. Body weight was reduced. The diet did not adversely affect plasma biochemical and enzyme profiles. L. lepideus reduced significantly plasma ${\beta}$- and pre-${\beta}$-lipoprotein, while ${\alpha}$-lipoprotein content was increased. A histological study of hepatic cells by conventional hematoxylin-eosin and oil red O staining revealed normal findings for mushroom-fed hypercholesterolemic rats. The present study suggests that a diet supplemented with L. lepideus can provide health benefits by acting on the atherogenic lipid profile in hypercholesterolemic rats.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2004년도 한국우주과학회보 제13권2호
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• pp.372-375
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• 2004

The UV radiometer payload was launched successfully from the west coastal area of Korea Peninsula aboard KSR-III on 28, Nov 2002. KSR-III was the Korean third generation sounding rocket and was developed as intermediate step to larger space launch vehicle with liquid propulsion engine system. UV radiometer onboard KSR-III consists of UV and visible band optical phototubes to measure the direct solar attenuation during rocket ascending phase. For UV detection, 4 channel of sensors were installed in electronics payload section and each channel has 255, 290, 310nm center wavelengths, respectively. 450nm channel was used as reference for correction of the rocket attitude during the flight. Transmission characteristics of all channels were calibrated precisely prior to the flight test at the Optical Lab. in KARI (Korea Aerospace Research Institute). During a total of 231s flight time, the onboard data telemetered to the ground station in real time. The ozone column density was calculated by this telemetry raw data. From the calculated column density, the vertical ozone profile over Korea Peninsula was obtained with sensor calibration data. Our results had reasonable agreements compared with various observations such as ground Umkhr measurement at Yonsei site, ozonesonde at Pohang site, and satellite measurements of HALOE and POAM. The sensitivity analysis of retrieval algorithm for parameters was performed and it was provided that significant error sources of the retrieval algorithm.

• 한국전자통신학회논문지
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• 제17권5호
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• pp.767-774
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• 2022

본 논문에서는 우리나라에서 운용 중인 4개 제조사 윈드프로파일러의 성능 평가 및 품질관리의 방향성을 제시하기 위해 원시 스펙트럼 자료를 분석하였다. 계절별로 평균한 스펙트럼의 프로파일과 파워 스펙트럼 밀도(PSD, Power Spectrum Density)로 산출한 4가지 통계값(최소, 평균, 중앙, 최댓값)의 프로파일을 활용하였다. 스펙트럼 자료의 품질은 LAP-3000이 가장 우수하였고, YKJ3, PCL-1300, CLC-11-H가 뒤를 이었다. 철원과 추풍령에 설치된 PCL-1300은 지형과 비기상 신호로 인한 스펙트럼의 변동성이 커서 지형 클러터 제거와 이동평균, 멀티피크 등의 신호처리 과정이 요구되었다. 군산과 파주에 설치된 CLC-11-H는 직류 치우침과 전파거리 접힘 현상이 발견되어 직류 치우침 제거와 관측 유효 고도 제한이 선행될 필요가 있다.

• Clinical Nutrition Research
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• 제13권1호
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• pp.22-32
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• 2024

Rheumatoid arthritis (RA) is a systemic inflammatory autoimmune disorder with widespread synovitis. Isoflavones, the main active component of soy, have been reported to have potent anti-inflammatory effects; the previous RA animal models showed the promising effect of soy supplementation. We aimed to evaluate the effect of soy bread on inflammatory markers and lipid profiles in RA patients. The present study was designed as a randomized controlled trial. RA patients were randomly allocated to obtain soy bread (n = 22) or placebo bread (n = 22) for 8 weeks. Fasting serum levels of lipid profile, total antioxidant capacity (TAC), tumor necrosis factor-α (TNF-α), C-reactive protein (CRP), and DAS28 were checked. Findings showed that there were no significant differences between the two groups in physical activity and dietary intake at the beginning of the study and the end of the study. There were no significant differences between the two groups in measured lipid profile markers, including high-density lipoprotein, low-density lipoprotein, total cholesterol, triglyceride, and very low-density lipoprotein, at the end of the trial. In addition, TAC and CRP also were not significant at the end of the trial between the 2 groups (0.66 and 0.12, respectively). However, the serum levels of TNF-α reduced significantly in the soy bread group at the end of the intervention (p < 0.000) and compared with the control group (p < 0.019). Soy bread consumption only decreased circulating TNF-α serum concentration. Other outcome measures were not changed following supplementation. Future long-term, well-designed studies are needed to confirm these findings.

• 한국방재학회 논문집
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• 제5권1호
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• pp.13-21
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• 2005

부서지기 쉬운 큰 응집입자의 파괴 없이 미립자의 침강거동에 관한 실험을 정지수면 조건하에서 CCD(Charged Coupled Device) 카메라로 실시하였다. CCD 카메라를 통한 실험은 점착성 미립자의 연직분포의 농도와 농도의 연직분포에 대해 물리-화학적 인자(NaCl, 밀도, 온도 및 pH)의 영향을 조사하는 것이다. 부유된 미립자(alumina와 quartz) 농도의 연직분포는 $20,000\;mg/{\ell}$까지 CCD 카메라로 측정할 수 있었다. 점착성 퇴적물의 농도의 연직분포는 초기농도의 증가, 온도의 증가 및 염분의 증가로 커진다. 그리고 염분의 첨가로 미립자(alumina) 농도의 연직분포가 quartz보다도 더 빠르게 감소한다. 그와 더불어서 PH은 미립자(alumina) 침강거동에 영향을 끼친다. pH 4.2에서 미립자의 침강률은 낮고, pH 8.9에서 입자의 응집현상 때문에 미립자의 침강률은 크다. pH 9부터 침강 평균속도는 감소한다.

• 한국지형학회지
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• 제26권4호
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• pp.21-31
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• 2019

Timing of terrace formation is a key information for understanding the evolution of fluvial systems. In particular, dating strath terrace (i.e. timing of terrace abandonment) is more difficult than depositional terrace that is conventionally constrained by radiocarbon, OSL and other dating methods targeting samples within terrace deposit. Surface exposure dating utilizing cosmogenic ¹⁰Be provides more reliability because it can be applied directly to the surface of a fluvial terrace. Thus, this method has been increasingly used for alluvial deposits. As well as other geomorphic surfaces over the last decades. Some inherent conditions, however, such as post-depositional ¹⁰Be concentration (i.e. inheritance), surface erosion rate, and density change challenge the application of cosmogenic ¹⁰Be to depositional terrace surface against simple bedrock surface. Here we present the first application of ¹⁰Be depth profile dating to a thin-gravel covered strath terrace in Korea. Monte Carlo simulation (MCS) helped us in better constraining the timing of abandonment of the strath terrace, since which its surface stochastically denuded with time, causing unexpected change of ¹⁰Be production with depth. The age of the strath terrace estimated by MCS was 109 ka, ~4% older than the one (104 ka) calculated by simple depth profile dating, which yielded the best-fit surface erosion rate of 2.1 mm/ka. Our study demonstrates that the application of ¹⁰Be depth profile dating of strath terrace using MCS is more robust and reliable because it considers post-depositional change of initial conditions such as erosion rate.