• Title/Summary/Keyword: FAO

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Applicability Analysis of FAO56 Penman-Monteith Methodology for Estimating Potential Evapotranspiration in Andong Dam Watershed Using Limited Meteorological Data (제한적인 기상자료 조건에서의 잠재증발산량 추정을 위한 FAO56 Penman-Monteith 방법의 적용성 분석 - 안동댐 유역을 사례로 -)

  • Kim, Sea Jin;Kim, Moon-il;Lim, Chul-Hee;Lee, Woo-Kyun;Kim, Baek-Jo
    • Journal of Climate Change Research
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    • v.8 no.2
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    • pp.125-143
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    • 2017
  • This study is conducted to estimate potential evapotranspiration of 10 weather observing systems in Andong Dam watershed with FAO56 Penman-Monteith (FAO56 PM) methodology using the meteorological data from 2013 to 2014. Also, assuming that there is no solar radiation data, humidity data or wind speed data, the potential evapotranspiration was estimated by FAO56 PM and the results were evaluated to discuss whether the methodology is applicable when meteorological dataset is not available. Then, the potential evapotranspiration was estimated with Hargreaves method and compared with the potential evapotranspiration estimated by FAO56 PM only with the temperature dataset. As to compare the potential evapotranspiration estimated from the complete meteorological dataset and that estimated from limited dataset, statistical analysis was performed using the Root Mean Square Error (RMSE), the Mean Bias Error (MBE), the Mean Absolute Error (MAE) and the coefficient of determination ($R^2$). Also the Inverse Distance Weighted (IDW) method was performed to conduct spatial analysis. From the result, even when the meteorological data is limited, FAO56 PM showed relatively high accuracy in calculating potential evapotranspiration by estimating the meteorological data.

Selection of Irrigation Desgin Year and Compparision of Reference Crop Evapotranspiration at 13 Regions (지역별 관개 계획기준년 선정과 기준작물 잠재증발산량 비교)

  • 김현수
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 1999.10c
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    • pp.93-98
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    • 1999
  • This study is performed to select irrigation design year from 10-year return period 7-month(April to October) precipitation amount and compare reference crop evapotranspiration at 13 regions by REF-ET model. 1. Seven-month growing season average reference crop evapotranspiration values showed low values of 4.1 ∼4.2mm /day by FAO-24 Corrected Penman method, and 3.6 ∼3.7mm/day by FAP-24 Blaney Criddle method in Chinjin and Ulsan, high values of 4.9mm/day by FAO-24 Corrected Penman method , 4.1mm/day by FAO -24 Blaney Criddle method in Mokpo and Pohang. 2. Estimated seven-month growing season average reference crop evapotranspirations are 4.6mm/day by FAO-24 Corrected Penman method, 3.9,mm/day by FAO-24 Balney Criddle method, 4.0mm/day 1985 Hargreaves method, respectively.

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Assessment of Reference Evapotranspiration Equations for Missing and Estimated Weather Data (기상자료의 결측과 산정에 따른 기준작물 증발산량 공식의 비교 평가)

  • Yoon, Pu Reun;Choi, Jin-Yong
    • Journal of The Korean Society of Agricultural Engineers
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    • v.60 no.3
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    • pp.15-25
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    • 2018
  • Estimating the reference evapotranspiration is an important factor to consider in irrigation system design and agricultural water use. However, there is a limitation in using the FAO Penman-Monteith (FAO P-M) equation, which requires various meteorological data. The purpose of this study is to compare three reference evapotranspiration (ETo) equations in the case of meteorological data missing for 11 study weather stations. Firstly, the FAO P-M equation is used for reference potential evapotranspiration estimation with the actual solar radiation data $R_n$ and the actual vapor pressure $e_a$. Then, in the case of $R_n$, and $e_a$ are missed, the reference evapotranspirations applying FAO P-M, Priestley-Taylor (P-T), Hargreaves (HG) equation were calculated using other meteorological factors. Secondly, MAE, RMSE, $R^2$ were calculated to compare ETo relationship from the ETo equations. From the results, ETo with Hargreaves equation in coastal areas and the Priestley-Taylor equation in the inland areas showed relatively high correlation with FAO P-M when $e_a$ data is missed. In the case of $R_n$ data is missed or two weather data, $e_a$, and $R_n$ data are all missed, $R^2$ value in Priestley-Taylor equation was highest in coastal areas, and $R^2$ values in Hargreaves equation were the high values for 7 inland areas. The results of sensitivity analysis showed that net radiation was the most sensitive for P-T and HG equation, and for FAO P-M, the most sensitive factor was net radiation and relative humidity, air temperature and wind speed were follows. Therefore, in considering of the accessibility to the coast, the types of the missing wether data, and the correlation and the magnitude of error, the reference evapotranspiration equations would be selected in sense of different conditions.

Hybridization and Use Of Grapes as an Oviposition Substrate Improves the Adaptation of Olive Fly Bactrocera oleae (Rossi) (Diptera: Tephritidae) to Artificial Rearing Conditions

  • Sohel, Ahmad;Viwat, Wornoayporn;Polychronis, Rempoulakis;Emily A., Fontenot;Ul Haq, Ihsan;Carlos, Caceres;Hannes F., Paulus;Marc J.B., Vreysen
    • International Journal of Industrial Entomology and Biomaterials
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    • v.29 no.2
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    • pp.198-206
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    • 2014
  • The olive fly Bactrocera oleae (Rossi) is the key pest for olive cultivation worldwide. Substantial effort has been invested in the development of the sterile insect technique (SIT) to control this pest. One of the limitations to develop SIT technology for olive fruit fly is the low ability of wild females to lay eggs in other medium than olive fruits, and their slow adaptation to oviposition in artificial substrates. In the present study, fruit grapes were used as an alternative egg collection medium to harvest eggs and young larvae from freshly colonized wild strains originating from France, Italy, Spain and Croatia. The larvae were allowed to develop into the fruits until the second instar, before they were extracted out and further reared on a standard artificial diet. Furthermore, F1 to F4 female flies were alternatively offered wax bottles to oviposit. Finally, the performance of hybrid strains created from crosses between wild and long colonised flies was assessed. The results showed that females of all 4 wild strains readily oviposited eggs in grapes and from the F2 generation onward, females from all strains were adapted to laying eggs in wax bottles. No difference was observed in eggs and pupae production among all strains tested. The findings are discussed for their implications on SIT application against olive fruit fly.

A point-scale gap filling of the flux-tower data using the artificial neural network (인공신경망 기법을 이용한 청미천 유역 Flux tower 결측치 보정)

  • Jeon, Hyunho;Baik, Jongjin;Lee, Seulchan;Choi, Minha
    • Journal of Korea Water Resources Association
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    • v.53 no.11
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    • pp.929-938
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    • 2020
  • In this study, we estimated missing evapotranspiration (ET) data at a eddy-covariance flux tower in the Cheongmicheon farmland site using the Artificial Neural Network (ANN). The ANN showed excellent performance in numerical analysis and is expanding in various fields. To evaluate the performance the ANN-based gap-filling, ET was calculated using the existing gap-filling methods of Mean Diagnostic Variation (MDV) and Food and Aggregation Organization Penman-Monteith (FAO-PM). Then ET was evaluated by time series method and statistical analysis (coefficient of determination, index of agreement (IOA), root mean squared error (RMSE) and mean absolute error (MAE). For the validation of each gap-filling model, we used 30 minutes of data in 2015. Of the 121 missing values, the ANN method showed the best performance by supplementing 70, 53 and 84 missing values, respectively, in the order of MDV, FAO-PM, and ANN methods. Analysis of the coefficient of determination (MDV, FAO-PM, and ANN methods followed by 0.673, 0.784, and 0.841, respectively.) and the IOA (The MDV, FAO-PM, and ANN methods followed by 0.899, 0.890, and 0.951 respectively.) indicated that, all three methods were highly correlated and considered to be fully utilized, and among them, ANN models showed the highest performance and suitability. Based on this study, it could be used more appropriately in the study of gap-filling method of flux tower data using machine learning method.

Study on Implications, Constructions and Changes of the FAO Technical Guidelines for Responsible Fisheries (FAO의 책임 있는 수산업을 위한 기술 지침의 의의, 구성 및 변화에 대한 연구)

  • LEE, Dongho
    • Journal of Fisheries and Marine Sciences Education
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    • v.27 no.6
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    • pp.1717-1726
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    • 2015
  • Acceleration of globalization in almost all industries, including fisheries, already had been a major paradigm of the age. And It has been weakened its meaning of geographical, cultural and economic boundaries between the nations. In particular, various changes in the fisheries environment have exceeded the area of problem for conventional single country is resolved. And if there is no cooperation with international cooperation other problems also almost nearly impossible to alleviate or solve. So it has emerged in this context, the concept of sustainable development and conceptual diagram of responsible fisheries. However, it has been passed about 20 years since the FAO documents published, there is little interest in it. In this study, analyzed the characteristics of the changes and its constitutive trends and contents of the FAO's responsible fisheries documents. And proposed both the need for analysis and research for the fisheries in an international context for the future and educational aspects. The results of this study show that FAO related documents are hardly to find that have been translated into Korean, in particular since the 2000s. And it is fairly skeptical whether there is a direct effective in fisheries in terms of language barriers. Therefore, the study on responsible fisheries much more important to develop the current status and future-oriented policy of international fisheries even in fisheries related education.

Surrogate Model for Potential Evapotranspiration Using a difference in Maximum and Minimum Temperature within a Hargreaves Modeling Framework (온도인자를 활용한 Hargreaves 모형 기반의 잠재증발산량 대체 모형 개발)

  • Kim, Ho Jun;Kim, Tae-Jeong;Lee, Kang Wook;Kwon, Hyun-Han
    • Proceedings of the Korea Water Resources Association Conference
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    • 2020.06a
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    • pp.184-184
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    • 2020
  • 수자원 계획 및 관리 시 증발산량의 정량적 분석은 필수적으로 고려되는 사항 중 하나이다. 일단위 이하의 잠재증발산량 산정은 세계식량기구(FAO)가 Penman-Monteith 방법을 기반으로 개발한 FAO56 PM 방법을 주로 활용하며, 이는 다른 방법에 비하여 높은 정확성과 적용성이 뛰어나다. 그러나 FAO56 PM 방법의 입력 매개변수는 다양한 기상자료이며, 장기간의 신뢰성 높은 자료를 구축하는 것은 어려운 실정이다. 이에 본 연구에서는 증발산량 공식인 Hargreaves 공식을 활용하여 FAO56 PM 방법으로 산정된 잠재증발산량과 기온차 사이의 시계열 관계를 재구성한 회귀분석 기법을 개발하였다. 개발된 모형에 유역면적을 적용하여 유역면적별 잠재증발산량을 산정하였으며, 이를 기존의 잠재증발산량과의 비교를 통해 모형의 적합성을 평가하였다. 결과적으로, 복잡한 잠재증발산량식을 단순한 대체모형(surrogate model)으로 제시함으로써 효율적인 증발산량 정량적 평가와 제한적인 기상자료 조건에 보편적 활용이 가능하다. 향후 연구에서는 회귀분석방법에 Bayesian 추론기법을 활용하여 구성함으로 잠재증발산량의 불확실성을 정량적으로 표현하고자 한다.

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A Study on International Cooperation and Information Service of the FAO/ASFA Database (FAO의 ASFA 데이터베이스 국제협력 및 정보서비스 연구)

  • 한종엽
    • Proceedings of the Korean Society for Information Management Conference
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    • 2000.08a
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    • pp.125-128
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    • 2000
  • 국제식량농업기구(FAO)에서는 해양수산분야 학문의 효율적인 연구활동 제고를 위하여 ASFA 데이터베이스의 세계적인 공동 협력 구축을 지원하고 있다. 이에 따라 ASFA DB의 국제상호협력 활동을 고찰하고 이와 유사한 타분야의 AGRIS, CARIS, INIS의 현황에 대해서도 비교 분석하였다. 또한 ASFA에서 제공되는 정보서비스에 대한 조사와 한국 자료입력센터의 지정과 역할 그리고 기대효과에 대하여 기술하였다.

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