기고논문 : 조직몰입의 제차원에 관한 연구

나상일 전주대학교 사회과학연구원 ( 구 사회과학종합연구소 ) 1997 정책과학논총 Vol.13 No.-

Spatial Downscaling of AMSR2 Soil Moisture Content using Soil Texture and Field Measurements

나상일,이경도,백신철,홍석영 한국토양비료학회 2015 한국토양비료학회지 Vol.48 No.6

Soil moisture content is generally accepted as an important factor to understand the process of crop growth and is the basis of earth system models for analysis and prediction of the crop condition. To continuously monitor soil moisture changes at kilometer scale, it is demanded to create high resolution data from the current, several tens of kilometers. In this paper we described a downscaling method for Advanced Microwave Scanning Radiometer 2 (AMSR2) Soil Moisture Content (SMC) from 10 km to 30 m resolution using a soil texture and field measurements that have a high correlation with the SMC. As a result, the soil moisture variations of both data (before and after downscaling) were identical, and the Root Mean Square Error (RMSE) of SMC exhibited the low values. Also, time series analyses showed that three kinds of SMC data (field measurement, original AMSR2, and downscaled AMSR2) had very similar temporal variations. Our method can be applied to downscaling of other soil variables and can contribute to monitoring small-scale changes of soil moisture by providing high resolution data.

Estimation of Highland Kimchi Cabbage Growth using UAV NDVI and Agro-meteorological Factors

나상일,홍석영,박찬원,김기덕,이경도 한국토양비료학회 2016 한국토양비료학회지 Vol.50 No.4

For more than 50 years, satellite images have been used to monitor crop growth. Currently, unmanned aerial vehicle (UAV) imagery is being assessed for analyzing within field spatial variability for agricultural precision management, because UAV imagery may be acquired quickly during critical periods of rapid crop growth. This study refers to the derivation of growth estimating equation for highland Kimchi cabbage using UAV derived normalized difference vegetation index (NDVI) and agro-meteorological factors. Anbandeok area in Gangneung, Gangwon-do, Korea is one of main districts producing highland Kimchi cabbage. UAV imagery was taken in the Anbandeok ten times from early June to early September. Meanwhile, three plant growth parameters, plant height (P.H.), leaf length (L.L.) and outer leaf number (L.N.), were measured for about 40 plants (ten plants per plot) for each ground survey. Six agro-meteorological factors include average temperature; maximum temperature; minimum temperature; accumulated temperature; rainfall and irradiation during growth period. The multiple linear regression models were suggested by using stepwise regression in the extraction of independent variables. As a result, NDVIUAV and rainfall in the model explain 93% of the P.H. and L.L. with a root mean square error (RMSE) of 2.22, 1.90 cm. And NDVIUAV and accumulated temperature in the model explain 86% of the L.N. with a RMSE of 4.29. These lead to the result that the characteristics of variations in highland Kimchi cabbage growth according to NDVIUAV and other agro-meteorological factors were well reflected in the model.

Estimation of Corn and Soybean Yields Based on MODIS Data and CASA Model in Iowa and Illinois, USA

나상일,홍석영,김예현,이경도 한국토양비료학회 2014 한국토양비료학회지 Vol.47 No.2

The crop growing conditions make accurate predictions of yield ahead of harvest time difficult. Suchpredictions are needed by the government to estimate, ahead of time, the amount of crop required to beimported to meet the expected domestic shortfall. Corn and soybean especially are widely cultivatedthroughout the world and a staple food in many regions of the world. On the other hand, the CASA(Carnegie-Ames-Stanford Approach) model is a process-based model to estimate the land plant NPP (NetPrimary Productivity) based on the plant growing mechanism. In this paper, therefore, a methodology for theestimation of corn/soybean yield ahead of harvest time is developed specifically for the growing conditionsparticular to Iowa and Illinois. The method is based on CASA model using MODIS data, and uses Net PrimaryProductivity (NPP) to predict corn/soybean yield. As a result, NPP at DOY 217 (in Illinois) and DOY 241 (inIowa) tend to have high correlation with corn/soybean yields. The corn/soybean yields of Iowa in 2013 wasestimated to be 11.24/3.55 ton/ha and Illinois was estimated to be 10.09/3.06 ton/ha. Errors were 6.06/17.58%and -10.64/-7.07%, respectively, compared with the yield forecast of the USDA. Crop yield distributions in2013 were presented to show spatial variability in the state. This leads to the conclusion that NPP changes inthe crop field were well reflected crop yield in this study.

RS/GIS를 이용한 토지이용변화에 의한 녹지의 이산화탄소 (CO₂) 흡착량 분포 추정

나상일,박종화,박진기,Na, Sang-Il,Park, Jong-Hwa,Park, Jin-Ki 한국농공학회 2010 한국농공학회논문집 Vol.52 No.3

Quantification of carbon absorption and understanding the human induced land use changes (LUC) forms one of the major study with respect to global climatic changes. An attempt study has been made to quantify the carbon absorption by LUC through remote sensing technology. The Landsat imagery four time periods was classified with the hybrid classification method in order to quantify carbon absorption by LUC. Thereafter, for estimating the amount of carbon absorption, the stand biomass of forest was estimated with the total weight, which was the sum of individual tree weight. Individual tree volumes could be estimated with the crown width extracted from digital forest cover type map. In particular, the carbon conversion index and the ratio of the $CO_2$ molecular weight to the C atomic weight, reported in the IPCC guideline, was used to convert the stand biomass into the amount of carbon absorption. Total carbon absorption has been modeled by taking areal estimates of LUC of four time periods and carbon factors for land use type and standing biomass. Results of this study, through LUC suggests that over a period of construction, 7.10 % of forest and 9.43 % of barren were converted into urban. In the conversion process, there has been a loss of 6.66 t/ha/y (7.94 %) of carbon absorption from the study area.

조직몰입의 제차원에 관한 연구

나상일 전주대학교 사회과학연구소 1997 社會科學論叢 Vol.13 No.-

Daum 이미지와 QuickBird 위성영상에 의한 NIR 밴드 추출과 정규화식생지수 (NDVI)에의 적용

나상일,박종화,Na, Sang-Il,Park, Jong-Hwa 한국농공학회 2009 한국농공학회논문집 Vol.51 No.4

This study extracted Near Infrared (NIR) band using Image Processing Technology (IPT), and calculated Normalized Difference Vegetation Index (NDVI). Aerial photography from Daum portal in combination with high resolution satellite image was employed to improve vegetation sensitivity by extracting NIR band and calculating NDVI with comparison to QuickBird result. The extracted NIR band and NDVI through IPT presented similar distribution pattern. In addition, a regression analysis by land cover character showed high correlation paddy and forest Therefore, this approach could be acceptable to acquire vegetation environment information.

RADARSAT-2 SAR를 이용한 서산 및 평양 지역의 벼 생육 모니터링 적용성 평가 -RapidEye와의 비교를 통해-

나상일,홍석영,김이현,이경도,Na, Sang Il,Hong, Suk Young,Kim, Yi Hyun,Lee, Kyoung Do 한국농공학회 2014 한국농공학회논문집 Vol.56 No.5

Radar remote sensing is appropriate for rice monitoring because the areas where this crop is cultivated are often cloudy and rainy. Especially, Synthetic Aperture Radar (SAR) can acquire remote sensing information with a high temporal resolution in tropical and subtropical regions due to its all-weather capability. This paper analyzes the relationships between backscattering coefficients of rice measured by RADARSAT-2 SAR and growth parameters during a rice growth period. And we applied the relationships to crop monitoring of paddy rice in North Korea. As a result, plant height and Leaf Area Index (LAI) increased until Day Of Year (DOY) 234 and then decreased, while fresh weight and dry weight increased until DOY 253. Correlation coefficients revealed that Horizontal transmit and Horizontal receive polarization (HH)-polarization backscattering coefficients were correlated highly with plant height (r=0.95), fresh weight (r=0.92), vegetation water content (r=0.91), LAI (r=0.90), and dry weight (r=0.89). Based on the observed relationships between backscattering coefficients and variables of cultivation, prediction equations were developed using the HH-polarization backscattering coefficients. Concerning the evaluation for the applicability of the LAI distribution from RADARSAT-2, the LAI statistic was evaluated in comparison with LAI distribution from RapidEye image. And LAI distributions in Pyongyang were presented to show spatial variability for unaccessible areas.

계층분류 기법을 이용한 위성영상 기반의 동계작물 구분도 작성

나상일,박찬원,소규호,박재문,이경도,Na, Sang-il,Park, Chan-won,So, Kyu-ho,Park, Jae-moon,Lee, Kyung-do 대한원격탐사학회 2017 大韓遠隔探査學會誌 Vol.33 No.5

In this paper, we propose the use of hierarchical classification for winter crop mapping based on satellite imagery. A hierarchical classification is a classifier that maps input data into defined subsumptive output categories. This classification method can reduce mixed pixel effects and improve classification performance. The methodology are illustrated focus on winter cropsin Gimje city, Jeonbuk with Landsat-8 imagery. First, agriculture fields were extracted from Landsat-8 imagery using Smart Farm Map. And then winter crop fields were extracted from agriculture fields using temporal Normalized Difference Vegetation Index (NDVI). Finally, winter crop fields were then classified into wheat, barley, IRG, whole crop barley and mixed crop fields using signature from Unmanned Aerial Vehicle (UAV). The results indicate that hierarchical classifier could effectively identify winter crop fields with an overall classification accuracy of 98.99%. Thus, it is expected that the proposed classification method would be effectively used for crop mapping. 본 연구에서는 위성영상 기반의 동계작물 구분도 작성을 위한 계층분류 기법을 제안한다. 계층분류 기법은 입력 자료를 계층별로 정의하여 분류하는 방법으로 혼합 픽셀의 효과를 줄이고 분류 성능을 향상시킬 수 있다. 이를 위하여 전북 김제시의 동계작물을 대상으로 Landsat-8 위성영상을 사용하였다. 먼저, Landsat-8 위성영상에서 스마트 팜 맵을 이용하여 농경지를 분류하였다. 그리고 추출된 농경지를 대상으로 시계열 식생지수를 사용하여 동계작물 재배지를 추출한 후, 최종적으로 무인기 영상에서 추출한 훈련자료를 활용하여 밀, 보리, IRG, 청보리 및 혼파 재배지로 분류하였다. 그 결과, 계층분류 기법에 의한 동계작물 분류 정확도는 98.99%로 동계작물별 재배 필지를 효과적으로 분류할 수 있는 것으로 나타났다. 따라서 제안된 분류방법은 작물구분도 작성에 효과적으로 사용 가능할 것으로 기대된다.

지방공무원의 직무만족과 조직몰입의 관계에 관한 실증분석

나상일 전주대학교 지방자치연구소 1997 自治行政硏究 Vol.- No.2