• 천문학회보
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• 제42권2호
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• pp.79.3-80
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• 2017

Molecular clouds are the sites of stellar birth. Turbulence is a natural phenomenon in molecular clouds, which largely determines the density and velocity fields. Additionally turbulent energy dissipation can affect the gas kinetic temperature via shocks. Turbulence thus controls the mode and tempo of star formation. However, despite its important role in star formation, the properties of turbulence remain poorly understood. As part of the Taeduk Radio Astronomy Observatory (TRAO) Key Science Program (KSP), "Mapping turbulent properties of star-forming molecular clouds down to the sonic scale (PI: Jeong-Eun Lee)", we have been mapping two star-forming clouds, the Orion A and the ${\rho}$ Ophiuchus molecular clouds in 3 sets of lines (13CO 1-0/C18O 1-0, HCN 1-0/HCO+ 1-0, and CS 2-1/N2H+ 1-0) using the TRAO 14-m telescope. We apply a Principal Component Analysis (PCA), which is an useful tool to represent turbulent power spectrum. We will present the preliminary results of our TRAO KSP toward two regions: OMC 1-4 in the Orion A cloud, and L1688 in the ${\rho}$ Ophiuchus cloud.

• 한국작물학회지
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• 제51권6호
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• pp.565-570
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• 2006

The viviparous germination (VG) with lodging caused the yield reduction and quality deterioration in rice. We carried out the evaluation of VG tolerance (on the 40th day after heading) and mapping QTLs associated with VG tolerance using the recombinant inbred lines (M/G RILs) from a cross between Milyang 23 (japonica/indica) and Gihobyeo (japonica). The VG rates of Milyang 23 and Gihobyeo were 0.0 and 7.0%, respectively. The averaged VG rate of 162 M/G RILs was 7.7%, and their range was from 0.0 to 50.9%. Of the 162 RILs, 144 lines were tolerant less than 10%, and 18 lines were susceptible more than 10%. Using the M/G RIL Map, three QTLs associated with the viviparous trait were detected on chromosome 2 (qVG 2-1 and qVG 2-2) and 8 (qVG 8). qVG 2-1 was linked to RM 32D and RZ 166, and had LOD score of 2.97. qVG 2-2 was tightly linked to E13M59.119-Pl and E13M59.M003-P2, and showed higher LOD score of 3.41. qVG 8 was linked to RM33 and TCT116, and had LOD score of 2.67. The total phenotypic variance explained by the three QTLs was about 24.4% of the total variance in the population. The detection of new QTLs associated with VG tolerance will provide important informations for the seed dormancy, low temperature germination, or comparative genetics.

• 대한원격탐사학회지
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• 제17권1호
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• pp.99-109
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• 2001

연안해역의 어장환경정비와 인공어초(Artificial Reef) 어장조성사업을 효과적으로 실시하기 위해서는 어장환경과 해양환경과의 관련을 종합적으로 분석하여 어초적지 지역을 선정하는 기법의 도입이 필요하다. 본 연구에서는 남해안 통영만 지역을 대상으로 인공어초 시설지 적지 선정에서 가장 중요하다고 판단되는 어초 적지조사 1단계 요소 중 수온, 클로로필, 투병도, 수심 해저지질조선을 위성원격탐사 자료와 GIS를 이용하여 공간분포도를 작성하고, 인공어초 시설지 적지조건에 따른 가중치를 부여하여 공간분석을 실시함으로써 인공어초 시설 예정지에 대한 적지를 선정하였다. 위성원격탐사와 GIS를 이용한 인공어초 적지 선정기법은 어초의 적지선정에 있어 필요한 다량의 자료를 정성 및 정량적으로 데이터베이스화하여 분석함과 동시에 가시화함으로써 지방자치단체에서 보다 효율적인 어초시설의 관리를 하도록 하는데 본 연구의 목적이 있다.

• 한국농공학회논문집
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• 제61권6호
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• pp.81-92
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• 2019

The objective of this study is to evaluate hydrologic impacts of climate change according to downscaling methods using the Soil and Water Assessment Tool (SWAT) model at watershed scale. We used the APCC Integrated Modeling Solution (AIMS) for assessing various General Circulation Models (GCMs) and downscaling methods. AIMS provides three downscaling methods: 1) BCSA (Bias-Correction & Stochastic Analogue), 2) Simple Quantile Mapping (SQM), 3) SDQDM (Spatial Disaggregation and Quantile Delta Mapping). To assess future hydrologic responses of climate change, we adopted three GCMs: CESM1-BGC for flood, MIROC-ESM for drought, and HadGEM2-AO for Korea Meteorological Administration (KMA) national standard scenario. Combined nine climate change scenarios were assessed by Expert Team on Climate Change Detection and Indices (ETCCDI). SWAT model was established at the Mankyung watershed and the applicability assessment was completed by performing calibration and validation from 2008 to 2017. Historical reproducibility results from BCSA, SQM, SDQDM of three GCMs show different patterns on annual precipitation, maximum temperature, and four selected ETCCDI. BCSA and SQM showed high historical reproducibility compared with the observed data, however SDQDM was underestimated, possibly due to the uncertainty of future climate data. Future hydrologic responses presented greater variability in SQM and relatively less variability in BCSA and SDQDM. This study implies that reasonable selection of GCMs and downscaling methods considering research objective is important and necessary to minimize uncertainty of climate change scenarios.

• 천문학회보
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• 제43권2호
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• pp.38.3-38.3
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• 2018

We present the results of high-resolution near-IR spectral mapping toward the Orion KL outflow. In this study, we used the Immersion Grating Infrared Spectrometer (IGRINS) on the 2.7 m Harlan J. Smith Telescope at McDonald Observatory. IGRINS's large wavelength coverage over the H & K bands and high spectral resolving power (R ~ 45,000) allowed us to detect over 35 shock-excited ro-vibrational H2 transitions and to measure directly the gas temperature and velocity of the dense outflows. In our previous study toward the H2 peak 1 region in the Orion KL outflow, we identified 31 outflow fingers from a datacube of the H2 1-0 S(1) $2.122{\mu}m$ line and constructed a three-dimensional map of the fingers. The internal extinction (${\Delta}AV$ > 10 mag) and overall angular spread of the flow argue for an ambient medium with a high density (105 cm-3). In this presentation, we show preliminary results of additional mapping toward a remarkable chain of bows (HH 205 - HH 207) farther from the ejection center, and obtain a more clear view of the shock physics of a single isolated bullet that improves on the knowledge gained from observations of the more complex peak 1 region in our earlier study.

• 대한기계학회논문집
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• 제16권6호
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• pp.1216-1220
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• 1992

본 연구에서는 Lee등의 연구를 일반화하기 위하여 급수 형태의 등각사상함수 로 표현되는 일반형태의 커스프형 강체함유물이 존재하는 경우에 대하여 복소 포텐셜 함수와 TSIF에 대한 일반해를 구하기로 한다.

• 제어로봇시스템학회논문지
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• 제22권5호
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• pp.367-373
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• 2016

In this paper, range measurement performance of LRF (Laser Range Finder) module and image contrast of color CCD camera are evaluated under the aerosol (high temperature steam) environments, which are simulated severe accident conditions of the LWR (Light-Water-Reactor) nuclear power plant. Data of LRF and color CCD camera are key informations, which are needed in the implementation of SLAM (Simultaneous Localization and Mapping) function for emergency response robot system to cope with urgently accidents of the nuclear power plant.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 1999년도 추계 학술대회논문집
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• pp.139-144
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• 1999

There have been many studies for heat transfer enhancement. Particularly, the study of flow in heat exchangers which have fin device has been main theme in heat transfer area. Practically, the circular tube which has internal fins is widely used for developing heat transfer rate. In this study, flow and heat transfer analysis of the circular tube with fins are investigated. The height and the number of fins are arbitrary. The flow field is assumed to be laminar. The conformal mapping is used for analytic solution of the laminar flow field. Discretization of governing equation, namely, FDM was used for numerical analysis. The velocity field, flow rate and shear stress are calculated for some numbers of fins in circular tube and for some heights of fin. Temperature fields are plotted along the tube length. It can be shown that the numerical solution agrees with the analytical solution.

• Journal of Power Electronics
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• 제18권3호
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• pp.910-922
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• 2018

Conventional battery state-of-charge (SoC) estimation methods either involve sophisticated models or consume considerable computational resource. This study constructs an enhanced coulomb counting method (Ah method) for the SoC estimation of lithium-ion batteries (LiBs) by expanding the Peukert equation for the discharging process and incorporating the Coulombic efficiency for the charging process. Both the rate- and temperature-dependence of battery capacity are encompassed. An SoC mapping approach is also devised for initial SoC determination and Ah method correction. The charge counting performance at different sampling frequencies is analyzed experimentally and theoretically. To achieve a favorable compromise between sampling frequency and accumulation accuracy, a frequency-adjustable current sampling solution is developed. Experiments under the augmented urban dynamometer driving schedule cycles at different temperatures are conducted on two LiBs of different chemistries. Results verify the effectiveness and generalization ability of the proposed SoC estimation method.

• Tribology and Lubricants
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• 제18권2호
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• pp.117-126
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• 2002

Abstract - An integrated condition monitoring algorithm based on an expert system was implemented in this work in order to monitor effectively the machine conditions. The knowledge base was consisted of numeric data which meant the posterior probability of each measurement parameter for the representative machine failures. Also the inference engine was constructed as a series of statistical process, where the probable machine fault was inferred by a mapping technology of pattern recognition. The proposed algorithm was, through the user interface, applied for an air compressor system where the temperature, vibration and wear properties were measured simultaneously. The result of the case study was found fairly satisfactory in the diagnosis of the machine condition since the predicted result was well correlated to the machine fault occurred.