• 농업생명과학연구
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• 제44권4호
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• pp.1-7
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• 2010

본 연구는 난대산림연구소의 제주시험림에 있는 서어나무 (Carpinus laxiflora)에 대한 개체목의 수간곡선식 추정 및 재적표를 개발하기 위하여 수행하였다. 최적의 추정식을 선택하기 위하여 Max & Burkhart식, Kozak식 및 Lee식을 적용하여 수간곡선식을 유도한 후, 각 식의 직경 추정에 대한 검정 통계량 및 실측치와 추정치간의 오차분포를 검증하였다. 그 결과 Max & Burkhart식 및 Lee식이 특정 구간에서 과대치 또는 과소 추정치를 보인데 반하여 Kozak식은 전구간에서 고른 분포를 보였다. 추정력이 가장 좋은 Kozak식을 활용하여 수피포함 재적표를 작성하였다.

• 대한원격탐사학회지
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• 제26권1호
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• pp.47-57
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• 2010

본 연구의 목적은 2006년 태풍 에위니아, 빌리스, 개미와 집중호우로 인해 많은 산사태가 발생한 진부면 지역을 대상으로 항공사진을 이용한 산사태 탐지 및 인공신경망과 GIS를 이용한 산사태 취약성을 분석하는데 있다. 산사태 위치는 산사태 발생 전후의 항공사진을 판독 후 현장에서 확인하였다. 취약성 분석을 위해 지형, 지질, 토양, 임상, 선구조, 토지이용도 등의 자료는 공간 데이터베이스로 구축하였다. 산사태와 관련 요인들간의 상대적 가중치는 인공신경망의 역전파 알고리즘을 이용하여 결정하였다. 그 결과 경사방향과 경사는 다른 요인들 보다 1.2~1.5배 높게 나타났다. 이 가중치를 이용하여 취약성도를 작성 후 분석에 사용하지 않은 산사태 위치와 비교하여 검증하였다. 그 결과 예측 정확도는 81.44%로 나타났다.

• 대한원격탐사학회지
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• 제24권5호
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• pp.483-496
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• 2008

Qualified ground control points (GCPs) are required to construct a digital elevation model (DEM) from a pushbroom stereo pair. An inverse geolocation algorithm for extracting GCPs from ERS SAR data and the SRTM DEM was recently developed. However, not all GCPs established by this method are accurate enough for direct application to the geometric correction of pushbroom images such as SPOT, IRS, etc, and thus a method for selecting and removing inaccurate points from the sets of GCPs is needed. In this study, we propose a method for evaluating GCP accuracy and winnowing sets of GCPs through orientation modeling of pushbroom image and validate performance of this method using SPOT stereo pair of Daejon City. It has been found that the statistical distribution of GCP positional errors is approximately Gaussian without bias, and that the residual errors estimated by orientation modeling have a linear relationship with the positional errors. Inaccurate GCPs have large positional errors and can be iteratively eliminated by thresholding the residual errors. Forty-one GCPs were initially extracted for the test, with mean the positional error values of 25.6m, 2.5m and -6.1m in the X-, Y- and Z-directions, respectively, and standard deviations of 62.4m, 37.6m and 15.0m. Twenty-one GCPs were eliminated by the proposed method, resulting in the standard deviations of the positional errors of the 20 final GCPs being reduced to 13.9m, 8.5m and 7.5m in the X-, Y- and Z-directions, respectively. Orientation modeling of the SPOT stereo pair was performed using the 20 GCPs, and the model was checked against 15 map-based points. The root mean square errors (RMSEs) of the model were 10.4m, 7.1m and 12.1m in X-, Y- and Z-directions, respectively. A SPOT DEM with a 20m ground resolution was successfully constructed using a automatic matching procedure.

• 대한원격탐사학회지
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• 제26권6호
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• pp.605-615
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• 2010

This study demonstrates the feasibility of small satellite, namely PROBA platform with the compact high resolution imaging spectrometer (CHRIS), for aerosol retrieval in Hong Kong. The rationale of our technique is to estimate the aerosol reflectances by decomposing the Top of Atmosphere (TOA) reflectances from surface reflectance and Rayleigh path reflectances. For the determination of surface reflectances, the modified Minimum Reflectance Technique (MRT) is used on three winter ortho-rectified CHRIS images: Dec-18-2005, Feb-07-2006, Nov-09-2006. For validation purpose, MRT image was compared with ground based multispectral radiometer measurements and atmospherically corrected Landsat image. Results show good agreements between CHRIS-derived surface reflectance and both by ground measurement data as well as by Landsat image (r>0.84). The Root-Mean-Square Errors (RMSE) at 485, 551 and 660nm are 0.99%, 1.19%, and 1.53%, respectively. For aerosol retrieval, Look Up Tables (LUT) which are aerosol reflectances as a function of various AOT values were calculated by SBDART code with AERONET inversion products. The CHRIS derived Aerosol Optical Thickness (AOT) images were then validated with AERONET sunphotometer measurements and the differences are 0.05~0.11 (error=10~18%) at 440nm wavelength. The errors are relatively small compared to those from the operational moderate resolution imaging spectroradiometer (MODIS) Deep Blue algorithm (within 30%) and MODIS ocean algorithm (within 20%).

• 대한원격탐사학회지
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• 제15권3호
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• pp.277-288
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• 1999

본 소고의 목적은 광범위한 시.공간적인 규모에서 일어나는 해양환경의 변화를 관측하기 위한 원격탐사기술의 활용을 전망하는 것이다. 현재 적용되고 있는 해양원격탐사의 기술과 발전 방향을 고찰하여 바람직한 해양원격탐사의 활용방안을 제시하였다. 해양원격탐사의 효율적인 활용을 위해서는 현안문제 해결과 수요자 위주의 관점에서 종합적 계획을 세워 추진하는 것이 바람직하다. 해양환경변화는 그 변화과정이 가지는 시간적 또는 공간적 규모에 맞추어 관측이 되어야 한다. 해양과 연안해역의 다양한 환경변화를 적절히 관측하고, 모니터링 하기 위해서는 이용 가능한 센서의 활용을 확대하여야 한다. 또한, 조사목적에 적합한 관측주기와 관측범위를 다양화하기 위하여 탑재대 (platform)의 종류도 다양화되어야 할 것이다. 현장관측치에 의한 보정과 검증과정은 해양원격탐사 자료의 바른 해석을 위해 반드시 요구되는 단계로 부이 시스템이나 기회성 선박을 적극 활용하는 종합관측망의 일부로 개발되어야 한다.

• 한국지형학회지
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• 제24권3호
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• pp.105-118
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• 2017

The debris slope landforms which are existent in Korean mountains is generally on the steep slopes and mostly covered by vegetation, it is difficult to investigate the landform. Therefore a scientific method is required to come up with an effective field investigation plan. For this purpose, the use of Remote Sensing and GIS technologies for a spatial analysis is essential. This study has extracted the potential area of debrisslope landform formation using Fuzzy set and Bayesian Predictive Discriminate Model as mathematical data integration methods. The first step was to obtain information about debris locations and their related factors. This information was verified through field investigation and then used to build a database. In the second step, the map that zoning the study area based on the degree of debris formation possibility was generated using two modeling methods, and then cross validation technique was applied. In order to quantitatively analyze the accuracy of two modeling methods, the calculated potential rate of debrisformation within the study area was evaluated by plotting SRC(Success Rate Curve) and calculating AUC(Area Under the Curve). As a result, the prediction accuracy of Fuzzy set model wes 83.1% and Bayesian Predictive Discriminate Model wes 84.9%. It showed that two models are accurate and reliable and can contribute to efficient field investigation and debris landform management.

• Perspectives in Nursing Science
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• 제16권2호
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• pp.84-97
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• 2019

Purpose: This study aimed to develop the Korean Prototype of Wellness Index (KP-WI) and identify the relationship between Koreans' health characteristics and wellness. Methods: The Wellness Index (WI) was translated into the primitive version of the KP-WI, considering the Koreans' culture and health behavior. It was administered to 223 service industrial employees at one workplace along with the Positive Affect and Negative Affect Schedule (PANAS) and Stress Questionnaire-Short Form. Data analyses included item-total correlation, Pearson's correlation coefficient, independent t-test, and one-way ANOVA. Results: The primitive version was modified to KP-WI based on the item-total correlation. The items considered to lower the reliability of the KP-WI were eliminated. Cronbach's ${\alpha}$ for each subscale ranged from .857 to .939. Perceived stress and negative emotions correlated significantly with wellness measured by KP-WI (r=-.29, p<.001; r=-.27, p<.001). Positive emotions correlated significantly with wellness (r=.60, p<.001). Conclusion: This study contributes to the development of Korean-style wellness indexes by developing a prototype and exploring the factors related to wellness.

• 대한원격탐사학회지
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• 제35권5_2호
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• pp.781-796
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• 2019

본 연구에서는 2016년 8월 태풍 "라이언록"으로 인해 극심한 피해를 입었던 회령시, 무산군 일대를 포함하고 있는 두만강 유역에 대하여 홍수특성을 분석하고자 하였다. 두만강 유역은 수문자료가 구축되어 있지 않은 미계측 유역이므로 원격탐사 자료를 통하여 유역특성 및 유출인자를 추정하여 홍수량 분석에 활용하였다. 대상유역에 대한 적용에 앞서 두만강 유역과 비교적 유역특성이 유사하고 계측자료 확보가 용이한 소양강댐 유역에 대하여 홍수유출분석을 실시함으로써 본 연구의 분석방법 및 자료의 적용성을 검증하였다. 분석결과, 태풍 "라이언록"으로 인한 홍수량은 3~5년 빈도 설계홍수량에 해당되는 것으로 향후에도 이 지역에 비슷한 수준의 홍수피해를 입을 가능성이 높음을 확인하였다. 마지막으로 본 연구를 통하여 수문관측자료가 부재한 미계측 지역에 대한 홍수량 산정시 원격탐사와 공간정보의 활용 가능성을 확인할 수 있었다.

• 한국농공학회논문집
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• 제61권6호
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• pp.1-8
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• 2019

Carbon dioxide is one of the major driving forces causing climate changes, and many countries have been trying to reduce carbon dioxide emissions from various sources. Soil stores more carbon dioxide(two to three times) amounts than atmosphere indicating that soil organic carbon emission management are a pivotal issue. In this study, we developed a Soil Organic Carbon(SOC) storage estimation model to predict SOC storage amounts in soils. Also, SOC storage values were assessed based on the carbon emission price provided from Republic Of Korea(ROK). Here, the SOC model calculated the soil hydraulic properties based on the soil physical and chemical information. Base on the calculated the soil hydraulic properties and the soil physical chemical information, SOC storage amounts were estimated. In validation, the estimated SOC storage amounts were 486,696 tons($3.526kg/m^2$) in Jindo-gun and shown similarly compared to the previous literature review. These results supported the robustness of our SOC model in estimating SOC storage amounts. The total SOC storage amount in ROK was 305 Mt, and the SOC amount at Gyeongsangbuk-do were relatively higher than other regions. But the SOC storage amount(per unit) was highest in Jeju island indicating that volcanic ashes might influence on the relatively higher SOC amount. Based on these results, the SOC storage value was shown as 8.4 trillion won in ROK. Even though our SOC model was not fully validated due to lacks of measured SOC data, our approach can be useful for policy-makers in reducing soil organic carbon emission from soils against climate changes.

• Wind and Structures
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• 제17권3호
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• pp.299-315
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• 2013

Numerical research on four typical configurations of noise mitigation structures and their characteristics of wind loads are reported in this paper. The turbulence model as well the model parameters, the modeling of the equilibrium atmospheric boundary layer, the mesh discretization etc., were carefully considered in the numerical model to improve the numerical accuracy. Also a numerical validation of one configuration with the wind tunnel test data was made. Through detailed analyses of the wind load characteristics with the inclined part and the wind incidence angle, it was found that the addition of an inclined part to a noise mitigation structure at-grade would affect the mean nett pressure coefficients on the vertical part, and that the extent of this effect depends on the length of the inclined part itself. The magnitudes of the mean nett pressure coefficients for both the vertical part and the inclined part of noise mitigation structure at-grade tended to increase with length of inclined part. Finally, a comparison with the wind load code British/European Standard BS EN 1991-1-4:2005 was made and the envelope of the mean nett pressure coefficients of the noise mitigation structures was given for design purposes. The current research should be helpful to improve current wind codes by providing more reasonable wind pressure coefficients for different configurations of noise mitigation structures.