• 한국농공학회논문집
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• 제56권2호
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• pp.11-23
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• 2014

The impact and adaption on agricultural water resources considering climate change is significant for reservoirs. The change in rainfall patterns and hydrologic factors due to climate change increases the uncertainty of agricultural water supply and demand. The quantitative evaluation method of uncertainty based on agricultural water resource management under future climate conditions is a major concern. Therefore, it is necessary to improve the vulnerability management technique for agricultural water supply based on a probabilistic and stochastic risk evaluation theory. The objective of this study was to analyse the uncertainty of water resources under future climate change using probability distribution function of water supply in agricultural reservoir and demand in irrigation district. The uncertainty of future water resources in agricultural reservoirs was estimated using the time-specific analysis of histograms and probability distributions parameter, for example the location and the scale parameter. According to the uncertainty analysis, the future agricultural water supply and demand in reservoir tends to increase the uncertainty by the low consistency of the results. Thus, it is recommended to prepare a resonable decision making on water supply strategies in terms of using climate change scenarios that reflect different future development conditions.

• 무역학회지
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• 제47권5호
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• pp.39-57
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• 2022

This study aims to analyze the factors influencing exports of agricultural products(HS01~HS24) from China to Korea by estimating the gravity model with panel data from 31 provinces in China. The results of the empirical analysis from the panel Tobit model are as follows: The effects of GDP and GDP per capita on agricultural exports are reversed, but their impacts are different on exports of each product, notably HS03, HS07 and HS20. As expected, distance decreases Chinese agricultural exports, and the impact of the relative exchange rate variable is also statistically significant, although it differs from product to product. However, differences in latitude, which considers the heterogeneity of climate and agricultural production conditions between Korea and each Chinese region, does not seem to affect agricultural exports to Korea. The road length, which affects the logistical conditions of each province in China, is not statistically significant either. On the other hand, increases in the number of Chinese visitors to Korea raises the amount of Chinese agricultural exports, including exports of HS03 and HS20. The results also shows that after the Korea-China FTA agreements, agricultural exports have actually decreased, especially exports of non-processed agricultural products, such as HS07.

• 한국식품영양학회지
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• 제36권2호
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• pp.129-136
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• 2023

In order to investigate the optimal UVB (ultraviolet B) treatment conditions for vitamin D₂ enhancement of freeze-dried ear mushroom, sample size (below 300 ㎛~whole), UV treatment temperature (30~60℃), treatment density (6.25~50.0 mg/cm²) and the samples mixing frequency (1~32 times) were treated differently. After that, chromaticity, vitamin D₂ and ergosterol (vitamin D₂ precursor) contents were investigated. As a result of the investigating, effective UVB treatment conditions for vitamin D₂ enhancement are as follows. The sample sizes were 2~4 mm and finely crushed pieces. The treatment temperatures were 50℃ and 60℃. The treatment density was 12.5 to 25.0 mg/cm², and the number of sample mixing was 8 times or more. As the amount of vitamin D₂ increased by UVB treatment, the ergosterol content generally tended to decrease. However, under some UVB treatment conditions, the vitamin D₂ content was not high despite the decrease of ergosterol content. Under the conditions set in this experiment, it was possible to obtain ear mushrooms with enhanced vitamin D₂ up to 26,968.7 ㎍/100 g. Therefore, it is thought that the ear mushroom is highly likely to be used as a vitamin D source and nutritionally fortified food ingredient.

• Mycobiology
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• 제33권1호
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• pp.30-34
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• 2005

This study investigated the biochemical changes of abnormal fruiting bodies grown under artificial environmental conditions in P. ostreatus. Abnormal mushroom growth during cultivation damages the production of good quality mushroom. This study showed that different environmental conditions produced morphological changes in the fruiting bodies of P. ostreatus. The fruiting bodies with morphological changes were collected and examined for differences in biochemical properties, enzyme activities, and carbohydrates composition. The enzyme activities assay showed that glucanase and chitinase activities decreased when the temperature was below or above the optimum cultivation temperature for P. ostreatus. The biochemical compositions of the abnormal mushroom were significantly different from the normal fruiting bodies. It was suggested that the changes in the biochemical composition of abnormal mushroom were caused by the unfavorable environmental conditions during mushroom cultivation.

• Journal of Biosystems Engineering
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• 제21권2호
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• pp.182-190
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• 1996

A macerating technique which can apply to the mechanical production system of the agricultural by-product was developed to increase the utilization of agricultural waste and solve the shortage problem in the forage supply for the livestock production. The macerating method is to shred the agricultural by-product by the two rolls which rotate at different speeds each other. The testing macerator was built and the optimum operating conditions are suggested. Results of this research are as follows: 1. The increase of the base roll speed and speed ratio between two rolls shows the better shredding index but decrease the drying rate. The optimum conditions of the base roll speed and the speed ratio between two rolls for the rice straw are 1200 rpm and 1.7-2.0 respectively. 2. The macerated alfalfa was dried to the 15%(w.b.) within 3 hrs in a field at speed ratio of rolls, 2:1 and base roll speed, 1800rpm. 3. The milled surface and straight knurled surface for the macerating roll have same effect on the drying rate of material. Both rolls have self-cleaning functions during operation.

• 한국농공학회논문집
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• 제64권4호
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• pp.45-53
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• 2022

In this study, the loading test and structural analysis were performed on the snow load and the results were compared. The load plates were loaded on the roof surface of the model, and structural analysis was performed under the same conditions. The result of loading test, the maximum displacement was observed in the center of the top, and the maximum stress was observed near the bottom point. Displacement and stress were found to have a high linear relationship with the load. Comparing the structural analysis results with the loading test results, the maximum displacement difference is 4.5% and the maximum stress difference is 10.2%. It is expected that closer results can be derived if the boundary conditions for the longitudinal direction of the model are clarified during experiments and analysis.

• 한국안전학회지
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• 제38권2호
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• pp.60-67
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• 2023

This study identified hazard exposures, health problems, and job satisfaction among elderly agricultural workers. A total of 1,340 agricultural workers (1,079 males and 261 females) were extracted from the 6^th Korean Working Conditions Survey data. Three age groups (A: 40s or below, B: 50s, and C: 60s or above) were statistically compared in hazard exposures, health problems, and job satisfaction. Elderly agricultural workers (60s or above) had significantly more exposure to ergonomic hazards, severe health problems, and lower job satisfaction than young agricultural workers. The study findings may help understand the characteristics of hazard exposures, health problems, and job satisfaction of elderly agricultural workers and will be useful for improving these conditions.

• 한국환경과학회지
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• 제33권1호
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• pp.97-102
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• 2024

We introduce a method for preserving yellow mealworm (Tenebrio molitor Linnaeus) larvae for an extended period and show that a high percentage of larvae can survive in good health under low-temperature storage conditions combined with specific diapause termination conditions. Our study revealed that we can regulate important development stages such as pupation, emergence, and larval duration by adjusting these termination conditions. When storing larvae aged 6-8 weeks for 140 days, the storage temperature can be varied based on our goals, giving us control over yellow mealworm production to meet specific demands. To produce adult beetles, storing larvae at 15 ℃ with wheat bran and ending diapause at 30 ℃ resulted in 90% pupation rate, with 60% becoming adults in 21 days. If our aim is larvae production, storing them at 10-12 ℃ with wheat bran and ending diapause at 25-30 ℃ allows the larvae to reach a suitable weight for processing. This straightforward approach ensures long-term storage of yellow mealworm larvae and provides a practical way to control their development, allowing efficient mass production tailored to market demands.

• 대한인간공학회지
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• 제30권4호
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• pp.525-534
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• 2011

This paper describes the current status of musculoskeletal disorders(MSDs) and its ergonomic risk factors, including the preventive intervention in terms of the working conditions and health promotion among agricultural workers. Korean agricultural workers have been exposed to the poor working condition. They have suffered from a variety of work-related injury and diseases more than the general population or the other occupational group. MSDs are one of the most prevalent problems threatening the agricultural worker's health and quality of life. Low back pain, osteoarthritis of hip and knee joint and carpal tunnel syndrome are well known MSDs that was found easily and frequently among agricultural workers. MSDs are worsened by poor ergonomic working conditions such as heavy weight lifting, repetitive movement and awkward posture which involves squatting with long sitting work on the ground, long working hours and heavy workload which are inherent in the greater part of agricultural works. Even though Korean agricultural workers are very weak population in terms of occupational safety and health, no many studies were conducted in the past and no many social and institutional supports were provided sufficiently. We need more interests and efforts in agricultural fields to improve its working condition and to promote health status of agricultural workers.

• International Journal of Industrial Entomology and Biomaterials
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• 제15권2호
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• pp.107-114
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• 2007

We investigated mating conditions of photoperiod, illumination and temperature during mating periods, care temperature of queen before mating, mating period and number of queen per mating cage to improve mating rate of Bombus ignitus. Among photoperiodic regimes of 12L, 14L and 16L during mating periods, queen mated at 14L showed better results than at 12L and 16L in egg-laying characteristics and colony development. In case of illumination during mating periods, intensity of 1000 lux was more effective than at intensity of 100 lux and 2000 lux in mating B. ignitus queen. Mating temperature and care temperature of queen before mating favorable for B. ignitus queen were $22-25^{\circ}C$ and $19^{\circ}C$, respectively. The period need to mating B. ignitus queen was 3 days, and the number of queen suitable per mating cage of $55{\times}45{\time}65\;cm$ was 30.