• Journal of Climate Change Research
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• v.5 no.4
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• pp.323-329
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• 2014

Since the terrain of Korea is complex, micro- as well as meso-climate variability is extreme by locations in Korea. In particular, air temperature of agricultural fields is influenced by topographic features of the surroundings making accurate interpolation of regional meteorological data from point-measured data. This study was carried out to compare spatial interpolation methods to estimate air temperature in agricultural fields surrounded by rugged terrains in South Korea. Four spatial interpolation methods including Inverse Distance Weighting (IDW), Spline, Ordinary Kriging (with the temperature lapse rate) and Cokriging were tested to estimate monthly air temperature of unobserved stations. Monthly measured data sets (minimum and maximum air temperature) from 588 automatic weather system(AWS) locations in South Korea were used to generate the gridded air temperature surface. As the result, temperature lapse rate improved accuracy of all of interpolation methods, especially, spline showed the lowest RMSE of spatial interpolation methods in both maximum and minimum air temperature estimation.

• Journal of Apiculture
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• v.33 no.4
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• pp.283-295
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• 2018

As Sacbrood virus (SBV), a causative agent of larval death and colony collapse in Apis cerana honey bee, is prevalent and poses one of the most significant threats to the Korean apiculture, development of methods to counter this viral disease is urgently needed. In this study we tested some SBV controlling methods, such as requeen, shook swam, adding Apis mellifera and spraying yogurt to SBV inoculated colony. Colony size measured by number of sealed brood and adult were evaluated every 15 days until two months while instances of recurrence were recorded up to five months after applying treatment methods. We also test the effects of yogurt on healthy and SBV-infected larvae at both in vitro reared larvae and colony level. Our result showed that all SBV controlling methods had similar success rates with respect to elimination of SBV clinical symptom up to 30 days post treatment. Mix-species and spraying yogurt method had similar pattern of sealed brood and adult number and higher than that of other SBV controlling methods up to 45 days post treatment. These two groups also showed the lower percentage of SBV recurrence (50% and 66.7%) at 120 days post treatment than other group that mostly colony had clinical symptom. Result on in vitro reared larvae challenged with yogurt showed that yogurt have neither harmless on healthy larvae nor remedial effect on SBV infected larvae. However, at colony level, colony in group received yogurt treatment removed significantly more SBV-infected larvae, SBV-killed larvae, and even healthy larvae in comparison to the control, suggested that yogurt could trigger the hygienic behavior of nurse bee. Our results recommended that it is practical in beekeeping by adding A. mellifera and spraying yogurt to control SBV in A. cerana colony.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.617-626
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• 1993

Energy saving is a very important subject for research workers nowadays. While most people are concerning with the modern methods, the authors investigated this problem from another angle- the chinese traditional methods of energy saving. The tunnel with technique and its combination with computer simulation and fuzzy compressive judgement methods are discussed. Earth heat green house, marsh gas, solar energy underground storage system, storing of nature cold sources, have been introduced in this paper.

• Journal of Biosystems Engineering
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• v.41 no.4
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• pp.389-395
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• 2016

Purpose: Drying is one of the most widely used methods for preserving agricultural products or food. The main purpose of drying agricultural products is to reduce their water content for minimizing microbial spoilage and deterioration reaction during storage. Methods: Although numerous drying methods are successfully applied to dehydrate various agricultural products with little drying time, the final quality of dried samples in terms of appearance and shape cannot be guaranteed. Therefore, based on published literature, this review was conducted to study the drying characteristics of various agricultural products when different drying methods were applied. Results: An increase in the drying power of sources-for example, increase in hot air temperature or velocity, infrared or microwave power-and the combination of drying power levels can reduce the drying time of various agricultural products. In addition, energy efficiency in drying significantly relies on the compositions of the dried samples and drying conditions. Conclusions: The drying power source is the key factor to control entire drying process of different samples and final product quality. In addition, an appropriate drying method should be selected depending on the compositions of the agricultural products.

• Proceedings of the Korean Society of Crop Science Conference
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• 2000.11a
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• pp.214-215
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• 2000

• Journal of The Korean Society of Agricultural Engineers
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• v.54 no.2
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• pp.37-46
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• 2012

The change of rainfall pattern and hydrologic factors due to climate change increases the occurrence probability of agricultural reservoir water shortage. Water supply assessment of reservoir is usually performed current reservoir level compared to historical water levels or the simulation of reservoir operation based on the water budget analysis. Since each reservoir has the native property for watershed, irrigation district and irrigation water requirement, it is necessary to improve the assessment methods of agricultural reservoir water capability about water resources system. This study proposed a practical methods that water supply vulnerability assessment for an agricultural reservoir based on a concept of probabilistic reliability. The vulnerability assessment of water supply is calculated from probability distribution of water demand condition and water supply condition that influences on water resources management and reservoir operations. The water supply vulnerability indices are estimated to evaluate the performance of water supply on agricultural reservoir system, and thus it is recommended a more objective method to evaluate water supply reliability.

• International Journal of Industrial Entomology and Biomaterials
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• v.33 no.2
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• pp.54-58
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• 2016

In natural conditions, the black soldier fly, Hermetia illucens (L.) (Diptera: Stratiomyidae), colonizes in warm temperate regions, and is active in Korea from May through October. Information on black soldier fly rearing, which is affected by seasonal factors in Korea, is limited. This species colonizes and oviposits in a wide variety of decomposing vegetable and animal matter. For mass rearing of black soldier flies, the egg deposition methods are dependent on sunlight and oviposition sites. In this study, we investigated the substrates and oviposition sites preferred by black soldier fly in artificial rearing system. Our results showed that as black soldier flies prefer mating under sunlight, they prefer ovipositing at sites where adequate sunlight and food substrate are available. Further detailed research is required to develop methods for artificially rearing black soldier fly throughout the year in Korea.

• Korean Journal of Agricultural Science
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• v.47 no.3
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• pp.633-644
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• 2020

Rice paper is an element of Vietnamese cuisine that can be used to wrap vegetables and meat. Rice and starch are the main ingredients of rice paper and their mixing ratio is important for quality control. In a commercial factory, assessment of food safety and quantitative supply is a challenging issue. A rapid and non-destructive monitoring system is therefore necessary in commercial production systems to ensure the food safety of rice and starch flour for the rice paper wrap. In this study, fluorescence hyperspectral imaging technology was applied to classify grain flours. Using the 3D hyper cube of fluorescence hyperspectral imaging (fHSI, 420 - 730 nm), spectral and spatial data and chemometric methods were applied to detect and classify flours. Eight flours (rice: 4, starch: 4) were prepared and hyperspectral images were acquired in a 5 (L) × 5 (W) × 1.5 (H) cm container. Linear discriminant analysis (LDA), partial least square discriminant analysis (PLSDA), support vector machine (SVM), classification and regression tree (CART), and random forest (RF) with a few preprocessing methods (multivariate scatter correction [MSC], 1^st and 2^nd derivative and moving average) were applied to classify grain flours and the accuracy was compared using a confusion matrix (accuracy and kappa coefficient). LDA with moving average showed the highest accuracy at A = 0.9362 (K = 0.9270). 1D convolutional neural network (CNN) demonstrated a classification result of A = 0.94 and showed improved classification results between mimyeon flour (MF)1 and MF2 of 0.72 and 0.87, respectively. In this study, the potential of non-destructive detection and classification of grain flours using fHSI technology and machine learning methods was demonstrated.

• Journal of Agricultural Extension & Community Development
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• v.14 no.1
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• pp.59-91
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• 2007

The objectives of this study were 1) to explore the present status of extension services of agricultural experiment station, and 2) to get some implications for ameliorating extension services of agricultural experiment station. The data were collected through the semi-constructed interviews with 11 agricultural researchers in 6 local agricultural experiment stations and 11 farmers who have ever made contact with the researchers. The major findings of this study were as follows: The agricultural experiment stations were providing extension services as expedients to accommodate to new markets and structural changes of organizations, though they are originally research-oriented agencies. The extension methods of agricultural experiment stations were similar with those of extension agencies, and the extension methods used mainly were 'experiment plot demonstration exhibition', 'consultation using telephone, internet, face to face meeting', 'visiting farms and consulting'. These were generally carried out by farmer's request, therefore the extension services of agricultural experiment stations were provided in a passive way so far. Based on the results of this study, the followings are recommended for further development of extension services of agricultural experiment station: The rural development organizations should set principles and support for extension services of agricultural experiment stations. The alternative plans to strengthen the linkage between research and extension have to be made, and these plans should include financial, personnel and systematic arrangements for further development of extension services of agricultural experiment stations.

• Journal of the Ergonomics Society of Korea
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• v.30 no.4
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• pp.473-480
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• 2011

Objective: This paper presents the results of a literature review undertaken to analyze the types and risk factors of unsafe posture in accordance with the crops and the working position and to introduce various ergonomic intervention approaches. Background: There is clear and consistent evidence that agricultural work has been rated as one of the dangerous occupations in the world. A considerable number of adverse health conditions, including musculoskeletal disorders(MSDs) are related to agricultural work. Method: An agricultural work requires squatting, kneeling, and bending(stooping) postures for significant periods of the work day which due to a wide variety of activities such as planting, cultivating and harvesting various agricultural products. Thus, each of these postures is analyzed in detail to recommend the improvement methods. Results: Various unsafe postures in agricultural works are revealed and analyzed. It is proven that ergonomics intervention has the potential benefits to reduce MSDs among agricultural workers. Two types of ergonomic intervention methods were discussed to improve unsafe working postures, engineering controls and administrative controls. Conclusion & Application: As a concluding remark, this article can be used as a reference manual for the agricultural workers and also used to raise the research community's awareness to the risk of unsafe working postures for workers in agriculture.