• Title/Summary/Keyword: Cdf3

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Construction of NCAM-LAMP Precipitation and Soil Moisture Database to Support Landslide Prediction (산사태 예측을 위한 NCAM-LAMP 강수 및 토양수분 DB 구축)

  • So, Yun-Yeong;Lee, Su-Jung;Choi, Sung-Won;Lee, Seung-Jae
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.22 no.3
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    • pp.152-163
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    • 2020
  • The present study introduces a procedure to prepare and manage a high-resolution rainfall and soil moisture (SM) database in the LAMP prediction system, especially for landslide researchers. The procedure also includes converting the data into spatial resolution suitable for their interest regions following proper map projection methods. The LAMP model precipitation and SM data are quantitatively and qualitatively evaluated to identify the model prediction characteristics using the ERA5 reanalysis precipitation and observed 10m depth SM data. A detailed process of converting LAMP Weather Research and Forecasting (WRF) output data for 10m horizontal resolution is described in a step-wise manner, providing technical convenience for users to easily convert NetCDF data from the WRF model into TIF data in ArcGIS. The converted data can be viewed and downloaded via the LAMP website (http://df.ncam.kr/lamp/index.do) of the National Center for AgroMeteorology. The constructed database will contribute to monitoring and prediction of landslide risk prior to landslide response steps and should be data quality controlled by more observation data.

Uncertainty in Regional Climate Change Impact Assessment using Bias-Correction Technique for Future Climate Scenarios (미래 기상 시나리오에 대한 편의 보정 방법에 따른 지역 기후변화 영향 평가의 불확실성)

  • Hwang, Syewoon;Her, Young Gu;Chang, Seungwoo
    • Journal of The Korean Society of Agricultural Engineers
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    • v.55 no.4
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    • pp.95-106
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    • 2013
  • It is now generally known that dynamical climate modeling outputs include systematic biases in reproducing the properties of atmospheric variables such as, preciptation and temerature. There is thus, general consensus among the researchers about the need of bias-correction process prior to using climate model results especially for hydrologic applications. Among the number of bias-correction methods, distribution (e.g., cumulative distribution fuction, CDF) mapping based approach has been evaluated as one of the skillful techniques. This study investigates the uncertainty of using various CDF mapping-based methods for bias-correciton in assessing regional climate change Impacts. Two different dynamicailly-downscaled Global Circulation Model results (CCSM and GFDL under ARES4 A2 scenario) using Regional Spectial Model for retrospective peiod (1969-2000) and future period (2039-2069) were collected over the west central Florida. Total 12 possible methods (i.e., 3 for developing distribution by each of 4 for estimating biases in future projections) were examined and the variations among the results using different methods were evaluated in various ways. The results for daily temperature showed that while mean and standard deviation of Tmax and Tmin has relatively small variation among the bias-correction methods, monthly maximum values showed as significant variation (~2'C) as the mean differences between the retrospective simulations and future projections. The accuracy of raw preciptiation predictions was much worse than temerature and bias-corrected results appreared to be more significantly influenced by the methodologies. Furthermore the uncertainty of bias-correction was found to be relevant to the performance of climate model (i.e., CCSM results which showed relatively worse accuracy showed larger variation among the bias-correction methods). Concludingly bias-correction methodology is an important sourse of uncertainty among other processes that may be required for cliamte change impact assessment. This study underscores the need to carefully select a bias-correction method and that the approach for any given analysis should depend on the research question being asked.

Identification of Artificial Operon Gene Expression via Yeast Mitochondrial Transformation (효모의 미토콘드리아 형질전환을 통한 인위적인 operon 형식의 유전자 발현 규명)

  • Kim Kyung-Min;Sul Il-Whan
    • Journal of Life Science
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    • v.16 no.3 s.76
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    • pp.365-368
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    • 2006
  • Yeast mitochondrial transformation has been confirmed by cell death and CFP expression (CDF: cell death factor gene). Expression vector containing CDF and CFP driven by one TPI (Triose-phosphate isomerase) promoter (called artificial operon type) was bombarded to Yeast. Interestingly, yeast cells were progressively deformed into unusual shapes and lysed inner cytoplasm resulting in ell death after all after bombarding with expression vector (CDC and GFP). Since there is no report about more than one gene expression simultaneously in a single mitochondria, this report is very important to novel type of eukaryotic gene expression. Successful yeast cell transformation in this report implies possible eukaryotic mitochodrial transformation including plants and animals and moreover two or more gene expression which can be excellent applicable protocols to pharmaceutical field including antibody production.

An embodiment of e-Science for High Energy Physics (고에너지물리 e-Science 연구환경의 구현)

  • Cho, Kihyeon;Kim, Hyunwoo
    • Proceedings of the Korea Contents Association Conference
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    • 2007.11a
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    • pp.231-233
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    • 2007
  • The e-Science for High Energy Physics is to study high energy physics anytime and anywhere even if we are not on-site of accelerator latboratories. The concepts are 1) data production, 2) data processing and 3) data publication. The data production is to do remote control and take shifts remotely. The data processing is to run jobs anytime, anywhere with grid farms. The data publication is to work together to publish papers using collaborative environment such as EVO (Enabling Virtual Organization) system. We apply this concept to high energy physics, espessically, CDF experiment and show the results.

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An approximate fitting for mixture of multivariate skew normal distribution via EM algorithm (EM 알고리즘에 의한 다변량 치우친 정규분포 혼합모형의 근사적 적합)

  • Kim, Seung-Gu
    • The Korean Journal of Applied Statistics
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    • v.29 no.3
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    • pp.513-523
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    • 2016
  • Fitting a mixture of multivariate skew normal distribution (MSNMix) with multiple skewness parameter vectors via EM algorithm often requires a highly expensive computational cost to calculate the moments and probabilities of multivariate truncated normal distribution in E-step. Subsequently, it is common to fit an asymmetric data set with MSNMix with a simple skewness parameter vector since it allows us to compute them in E-step in an univariate manner that guarantees a cheap computational cost. However, the adaptation of a simple skewness parameter is unrealistic in many situations. This paper proposes an approximate estimation for the MSNMix with multiple skewness parameter vectors that also allows us to treat them in an univariate manner. We additionally provide some experiments to show its effectiveness.

Measure and Analysis of Open-Close Frequency of Mouth and Eyes for Sleepiness Decision (졸음 판단을 위한 눈과 입의 개폐 빈도수 측정 및 분석)

  • Sung, Jae-Kyung;Choi, In-Ho;Park, Sang-Min;Kim, Yong-Guk
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.14 no.3
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    • pp.89-97
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    • 2014
  • In this paper, we propose real-time program that measure open-close frequency of mouth and eyes to detect drowsiness of a driver. This program detects a face to the CCD camera image using OpenCV library. Then that extracts each area using CDF for eye detection and Active Contour for mouth detection based on detected face. This system measures each frequency of Open-Close using extracted area data of eyes and mouth. We propose foundation technique how to perform sleepiness decision of users based on measurement data.

Design Enhancements of Automatic Depressurization System in a Passive PWR (피동형 경수로 자동감압계통의 개선에 관한 연구)

  • Yu, Sung-Sik;Seong, Poong-Hyun
    • Nuclear Engineering and Technology
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    • v.25 no.4
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    • pp.515-528
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    • 1993
  • In a Passive PWR, the successful actuation of Automatic Depressurization System (ADS) is essentially required so that no core damage is occurred following small LOCA. But it has been shown in the previous studies that Core Damage Frequency (CDF) from small LOCA is significantly caused by unavailability of ADS. In this study, the design vulnerabilities impacting the ADS unavailability have been identified and the design improvement items have been proposed through the system reliability assessment using the fault tree methodology The impacts on CDF according to the change of system unavailability have also been analyzed. In addition, small LOCA simulation using RELAP5/MOD3 code has been performed to show the thermal-hydraulic feasibility of the suggested design enhancements.

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A Study on the Propagation Characteristics of Polarization Diversity in rural and Residential Areas (교외 및 주거 지역에서의 편파 다이버시티 전파전파 특성 연구)

  • 임종태;김성진;유봉국
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.9 no.3
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    • pp.369-377
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    • 1998
  • In this paper, we performed the comparisons between polarization diversity using dual polarization antennal which has $\pm45^{\circ}$slanted linear polarization characteristics and conventional space diversity in rural and residential areas. The analysis was done by evaluating the diversity gain improvement and cross correlation coefficients between two received signals through each diversity branch. From the results, we could confirmed that space diversity has bigger diversity gain than polarization diversity by 1~2 dB, and there is a little difference of $\pm0.1$ in cross correlation coefficients by analyzing CDF under portable mobile phone environments.

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A NOTE ON THE CHARACTERIZATIONS OF THE GUMBEL DISTRIBUTION BASED ON LOWER RECORD VALUES

  • Jin, Hyun-Woo;Lee, Min-Young
    • Journal of the Chungcheong Mathematical Society
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    • v.30 no.3
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    • pp.285-289
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    • 2017
  • Let $\{X_n,\;n{\geq}1\}$ be a sequence of independent and identically distributed random variables with cdf F(x) which is absolutely continuous with pdf f(x) and F(x) < 1 for all x in ($-{\infty},\;{\infty}$). In this paper, we obtain the characterizations of the Gumbel distribution by lower record values.