• 한국식품영양과학회지
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• 제42권9호
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• pp.1351-1356
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• 2013

삼채를 식품으로써 활용도를 높이기 위하여 노지 및 하우스 재배에 의한 삼채의 뿌리 및 잎에 대한 식품학적인 특성을 조사하였다. 삼채의 수분함량은 뿌리에서 81.05~84.18%, 잎에서는 88.85~90.12%이었으며, 가용성 무질소물인 탄수화물군은 뿌리에서 13.49~16.20%, 잎에서는 7.08~7.79%를 함유하고 있었다. 무기질 성분 중 가장 많은 무기질은 노지 및 하우스 재배 모두 K으로 잎에서는 503.98~512.08 mg%를 함유하고 있었다. 노지 재배에 의한 삼채는 뿌리 중 유리당 함량이 잎 부위보다 약 4배 이상 높은 함량이었고, 하우스 재배 삼채는 뿌리보다 잎에서 약 3배 이상 높았다. 특히 fructose의 경우는 하우스 재배 삼채보다 노지 재배 삼채 뿌리가 약 12배 정도 더 높았다. 삼채의 조사포닌 및 총폴리페놀 함량은 뿌리보다 잎에서, 하우스 재배보다 노지 재배 삼채에서 더 많이 함유하고 있었다. 노지 및 하우스 재배 삼채의 뿌리와 잎 부위 추출물에 대한 DPPH radical 소거활성은 70% MeOH 잎 추출물에서 훨씬 소거활성이 높았으며 특히 하우스 재배 삼채 잎의 70% MeOH 추출물은 소거활성이 가장 높아 $IC_{50}$의 값이 2.74 mg/mL이었다. 마우스 대식세포에서의 세포증식에 미치는 영향에서는 하우스 재배 삼채 잎의 물 및 70% 메탄올 추출물 모두 가장 높은 농도인 10배 희석액을 처리하여서도 독성이 없었으며 LPS로 유도처리한 RAW 264.7 대식세포에서 NO의 생성을 억제현상은 70% 메탄올 추출물에서는 노지 및 하우스 재배 모두 농도 의존적으로 NO의 생성을 억제하였다. 특히 노지 재배 삼채 잎에서는 독성이 나타나지 않는 90배 희석액 처리 시에도 NO의 생성을 강하게 저해시켰다.

• 천문학회지
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• 제43권4호
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• pp.115-121
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• 2010

UBVI CCD photometry is obtained for the Ruprecht 93 (Ru 93)region. We are unable to confirm the existence of an intermediate-age open cluster in Ru 93 from the spatial distribution of blue stars. On the other hand, we find two young star groups in the observed field: the nearer one (Ru 93 group) comprises the field young stars in the Sgr-Car arm at $d{\approx}2.1$ kpc, while the farther one (WR 37 group) is the young stars around WR 37 at $d{\approx}4.8$ kpc. We derive an abnormal extinction law ($R_V$ = 3.5) in the Ruprecht 93 region.

• 천문학논총
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• 제32권1호
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• pp.37-39
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• 2017

We present the first results of a new data analysis pipeline for processing extragalactic AKARI/IRC images. The main improvements of the pipeline over the standard analysis are the removal of Earth shine and image distortion correction. We present the differential number counts of the AKARI/IRC S11 filter in the IRAC validation field. The differential number counts are consistent with S11 AKARI NEP deep and $12{\mu}m$ WISE NEP number counts, and with a phenomenological backward evolution galaxy model, at brighter fluxes densities. There is a detection of fainter galaxies in the IRAC validation field.

• 천문학회보
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• 제41권2호
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• pp.53.2-53.2
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• 2016

We present our experiences with open-source spatio-temporal database systems for managing and analyzing big astronomical data acquired by wide-field time-domain sky surveys. Considering performance, cost, difficulty, and scalability of the database systems, we conduct comparison studies of open-source spatio-temporal databases such as GeoMesa and PostGIS that are already being used for handling big geographical data. Our experiments include ingesting, indexing, and querying millions or billions of astronomical spatio-temporal data. We choose the public VVV (VISTA Variables in the Via Lactea) catalogs of billions measurements for hundreds of millions objects as the test data. We discuss issues of how these spatio-temporal database systems can be adopted in the astronomy community.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제49권7호
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• pp.457-461
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• 2000

The finite element method (FEM) is suitable for the analysis of a complicated region that includes nonlinear materials, whereas the boundary element method (BEM) is naturally effective for analyzing a very large region with linear characteristics. Therefore, considering the advantages in both methods, a novel algorithm for the alternate application of the FEM and BEM to magnetic field problems with the open boundary is presented. This approach avoids the disadvantages of the typical numerical methods with the open boundary problem such as a great number of unknown values for the FEM and non-symmetric matrix for the Hybrid FE-BE method. The solution of the overall problems is obtained by iterative calculations accompanied with the new acceleration method.

• International Journal of Naval Architecture and Ocean Engineering
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• 제13권1호
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• pp.35-49
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• 2021

This paper presents a direct numerical simulation of turbulent flows over a bump in an open channel to examine the turbulence characteristics near divergent waves emanating from the bump and to investigate the interaction of the turbulences with the divergent waves. To verify the reliability of the simulations, the mean velocity profile and root-mean-square of velocity fluctuations are compared with previous data. The anisotropic invariant maps show that the ratio of the streamwise to spanwise velocity fluctuations plays an important role in characterizing the anisotropic nature of the separated shear layer behind the bump in the vicinity of the free surface. The vortex identification discloses a large-scale streamwise vortical structure from the mean velocity field and a cluster of small coherent structures from the instantaneous velocity field, which are responsible for the anisotropic characteristics of the turbulence beneath the free surface.

• Geomechanics and Engineering
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• 제32권1호
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• pp.111-123
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• 2023

The slope of an open cut tunnel is located above the exit of the Leijia tunnel on the Changgan high-speed railway. During the excavation of the open cut tunnel foundation pit, the slope slipped twice, a large landslide of 92500 m³ formed. The landslide body and unstable slope body not only caused the foundation pit of the open cut tunnel to be buried and the anchor piles to be damaged but also directly threatened the operational safety of the later high-speed railway. Therefore, to study the stability change in the slope of the open cut tunnel under heavy rain and excavation conditions, a 3D numerical calculation model of the slope is carried out by Midas GTS software, the deformation mechanism is analyzed, anti-sliding measures are proposed, and the effectiveness of the anti-sliding measures is analyzed according to the field monitoring results. The results show that when rainfall occurs, rainwater collects in the open cut tunnel area, resulting in a transient saturation zone on the slope on the right side of the open cut tunnel, which reduces the shear strength of the slope soil; the excavation at the slope toe reduces the anti-sliding capacity of the slope toe. Under the combined action of excavation and rainfall, when the soil above the top of the anchor pile is excavated, two potential sliding surfaces are bounded by the top of the excavation area, and the shear outlet is located at the top of the anchor pile. After the excavation of the open cut tunnel, the potential sliding surface is mainly concentrated at the lower part of the downhill area, and the shear outlet moves down to the bottom of the open cut tunnel. Based on the deformation characteristics and the failure mechanism of the landslides, comprehensive control measures, including interim emergency mitigation measures and long-term mitigation measures, are proposed. The field monitoring results further verify the accuracy of the anti-sliding mechanism analysis and the effectiveness of anti-sliding measures.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집E
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• pp.349-354
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• 2001

The present study addresses the open end correction associated with the reflection and discharge phenomena of a weak shock wave from an open end of a duct. The open end correction of the weak shock wave is investigated experimentally and by numerical computation. An experiment is made using a simple shock tube with an open end, and computation is performed to simulate the experimental flow field using the unsteady, axisymmetric, compressible, flow governing equations. The results obtained show that an open end correction should be involved for shock wave discharge and reflection problems generated from the exit of the duct with an open end baffle plate. With a baffle plate less than three times the duct diameter, it is found that the open end correction is a function of both the diameter of the baffle plate and normal shock wave magnitude. However, for a baffle plate larger than three times the duct diameter, it is independent of the baffle plate diameter. The present computations predict the results of shock tube experiment with good accuracy. A new empirical equation for prediction of the open end correction is found for the weak shock reflection and discharge phenomena occurring at the open end of the duct with and without a baffle plate.

• 한국소음진동공학회논문집
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• 제11권7호
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• pp.239-246
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• 2001

The present study addresses the open correction associated with the reflection and discharge phenomena of a weak shock wave from an open end of a duct. The open correction of the weak shock wave is investigated experimentally and by numerical computation. An experiment is made using a simple shock tube with an open end. and computaion is performed to simulate the experimental flow field using the unsteady, axisymmetric compressible. flow governing equations. The results obtained show the an open correction should be involved for shock wave discharge and reflection problems generated from the exit of the duct with an open baffle plate. With a baffle plate less than three times the duct diameter, it is found that the open end correction is a function of both the diameter of the baffle plate and normal shock wave magnitude However, for a baffle plate larger than three the duct diameter it is independent of the baffle plate diametre, The present computations predict the results of shock tube experiment with good accuracy. A new empirical equation for prediction of the open correction is found for the weak shock reflection and discharge phenomena occurring at the open of the duct with and without a baffle plate.

• 한국도서관정보학회지
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• 제51권4호
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• pp.83-100
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• 2020

오픈 사이언스 시대 연구데이터의 공개를 가속화하고 접근성 및 인용가능성 개선 및 연구데이터에 대한 표준화된 기술문서 제공은 또 다른 과학적 발견에 기여할 수 있어 데이터 출판이 주목을 받고 있다. 또한 출판된 데이터 역시 연구논문과 동등한 지위를 유지할 수 있는 방안으로 데이터 논문이 대두되고, 새로운 학술출판의 유형으로 데이터 저널 발간이 증가추세에 있다. 특히 생태학 분야는 대규모 연구데이터가 생산되고 관리되어야 하는 분야로 전세계적으로 데이터 저널 발간이 활발하다. 반면 국내에는 데이터 저널 연구가 초기 단계이고, 생태학 분야 데이터 저널이 전무하다. 이에 본 연구에서는 생태 분야의 데이터 저널을 발간하기 위한 전략을 탐색하고 제시하였다. 먼저 국내외 데이터 저널 발간 현황과 국내 저널 출판 현황을 조사하였다. 또한 학술출판 및 오픈액세스 정책 전문가, 생태학 학술지 발간 전문가로 구성된 전문가그룹 인터뷰를 수행하였다. 현재 데이터 저널 발간 인프라가 제대로 구축되지 않고 이에 대한 평가체제가 갖추어 지지 않은 국내 학술출판 관행을 반영하고 국내외 조사결과와 전문가 FGI를 실시 결과를 바탕으로 생태학 분야 데이터 저널 출간 방향, 데이터 논문 투고지침, 저널 구성 및 발행주기, 저널 편집위원 구성, 원고의 수급 측면에서 전략을 제시하였다.