• Mycobiology
• /
• 제34권4호
• /
• pp.200-205
• /
• 2006

Phellinus genus belonged to Hymenochaetaceae of Basidiomycetes and has been well known as one of the most popular medicinal mushrooms due to high antitumor activity. This study was carried out to obtain the basic information for mycelial culture conditions of Phellinus linteus, P. baumii, and P. gilvus. According to colony diameter and mycelial density, the media for suitable mycelial growth of them were shown in MEA, glucose peptone, and MCM. The optimum temperature for mycelial growth was $30^{\circ}C$. Carbon and nitrogen sources were man nose and malt extract, respectively. The optimum C/N ratio was 10:1 to 5:1 with 2% glucose concentration, vitamin was thiamine-HCl, organic acid was succinic acid, and mineral salt was $MgSO_{4}{\cdot}7H_{2}O$.

• 드라이브 ㆍ 컨트롤
• /
• 제20권3호
• /
• pp.25-34
• /
• 2023

In this study, we conducted a research on optimizing the spraying performance of agricultural drones and predicted the spraying performance in various flight conditions using the multi-layer perceptron (MLP). Data was collected using a test device for pesticide spraying performance according to the water sensitive paper (WSP) evaluation. MLP training involved supervised learning to achieve a coefficient of variation (CV), which indicates the degree of uniform spraying. The performance evaluation was conducted using R-squared (R²), the test samples showed an R² of 0.80. The results of this study showed that drone spraying performance can be predicted under various flight environments. In addition, the correlation analysis between flight conditions and predicted spraying performance will be useful for further research on optimizing the spraying performance of agricultural drones.

• 드라이브 ㆍ 컨트롤
• /
• 제21권2호
• /
• pp.30-35
• /
• 2024

Domestic rice is more expensive than imported products, so it is necessary to reduce production costs to secure competitiveness. Low-density planting developed in Japan is a cultivation technology that reduces labor and production costs without yield loss. The area of low-density cultivation is continuously increasing. However, research on how rice transplanters adapt to low-density planting has not been conducted. Therefore, this study was carried out to determine the optimal working conditions of a rice transplanter for low-density planting. Three types of rice transplanters were used and treated based on 3 conveying distance levels. The number of picked seedlings, pick missing rate, the number of planted seedlings, and the mis-planted rate were investigated to evaluate planting accuracy according to the transfer distance to the seedling tray. The results showed that the number of planted seedlings was 4.31~4.95 EA with an L1 seedling tray transfer distance (horizontal 9 mm, vertical 8 mm), but the mis-planted rate was higher than in other conditions. At L2 (horizontal 9 mm, vertical 10 mm) and L3 (horizontal 11 mm, vertical 8 mm) transfer distance conditions, the number of planted seedlings were 4.89-5.68 EA and 4.69-5.66 EA, respectively, with a low mis-planted rate of less than 3%. The results showed that if the transfer distance is adjusted properly, a rice transplanter can be used for low-density planting with high planting accuracy.

• 한국산업보건학회지
• /
• 제32권4호
• /
• pp.287-301
• /
• 2022

Objectives: This study compared the characteristics of the work environment between agricultural and general workers and analyzed the effects of agricultural working characteristics on work-related health problems. Methods: The participants of this study were 2,347 agricultural workers and 48,042 general workers who were selected by applying standardized weights to the raw data of 50,538 respondents from the 6th Korean Working Condition Survey (KWCS). Variables applicable to both worker groups and related to exposure to hazardous risk factors in the working environment, working hours and intensity of work, health problems and work-related status, and satisfaction with the work environment were selected. Chi-square tests and independent sample t-tests were performed to evaluate the differences in the variables between the two groups. Multivariate logistic regression analysis was conducted to analyze the effects of work environment characteristics on work-related health problems. Results: Compared to general workers, agricultural workers were more exposed to hazardous environments, irregular work patterns such as working on Saturday/Sunday, and short repetitive tasks. They reported more work-related and general health problems, including back pain, upper extremity muscle pain, lower extremity muscle pain, and general fatigue. Agricultural workers showed lower satisfaction with their work environment than general workers. Factors affecting one or more work-related health problems included gender, working years, hazardous factors, irregular work pattern, working hours, and labor intensity. Conclusions: Our findings showed that agricultural workers were relatively more vulnerable to safety issues compared to other occupational groups. Therefore, it is necessary to establish standardized safety and health standards and strengthen systematic safety and health management policies and services for agriculture.

• 농촌지도와개발
• /
• 제3권1호
• /
• pp.1-16
• /
• 1996

The purpose of this study was to interpret the transformation of Cooperative Groups for Agricultural Production(CGAP) with the change of the Agricultural Productive Force. The specific objectives were; 1) To investigate the change of agricultural labour-power, 2) To investigate the change of agricultural mechanization and arable land, 3) To interpret the transformation and content of CLAP. The population of farmhouseholds has decreased continuously since the late 1960s. Especially, with the move-outs of youth ages of twenties to forties, the condition of agricultural labour-power has been more serious. The processing of agricultural mechanization was a small scale step in the 1970s, but after the 1980s there was a spread of middle-large machines. However the usage rate of agricultural machines was constrained by the bad conditions of arable land. From the 1970s to now, the CGAP have bean processed by many kinds of patterns. In the 1970s, the lack of labour-power caused the creation of the Co-Working Team. After the late of 1970s, the wage of agricultural employees was raised, because the working population of agriculture was cut down. Also, the induction of agricultural machine was promoted. As a result, in the 1980s, the Machine-Using Team occurred due to these conditions of agricultural productive force. In the late of 1980s, the population decreased more rapidly, and the use of large machines were spread. Than farmhouseholds laking labour-power gave a trust to other farmhouseholds and Teams which had machines. In 1990, Given-Trust Cooperations were enacted by law, and in order to overcome the lack of labour-power, and solve the problem of the successors of agriculture, Cooperative Organizations were also enacted by law. Finally, in Korea from the 1970s to now, as the agricultural productive force has barn changed, the Co-Working Team was transformed into the Machine-Using Team, and the Machine-Using Team was transformed into the Given-Trust Cooperation, and the Cooperative Organization.

• Journal of Microbiology and Biotechnology
• /
• 제29권7호
• /
• pp.1053-1060
• /
• 2019

Thermal drying is a common process used in the food industry for the modification of agricultural products. However, while various studies have investigated the alteration in physiochemical properties and chemical composition after drying, research focusing on the relationship between different dehydration conditions and bioactivity is scarce. In the current study, we prepared dried ginger under nine different conditions by varying the processing time and temperature and compared their immunomodulatory effects. Interestingly, depending on the drying condition, there were significant differences in the immunestimulating activity of the dried ginger samples. Gingers processed at $50^{\circ}C$ 1h displayed the strongest activation of macrophages measured by $TNF-{\alpha}$ and IL-6 levels, whereas, freezedried or $70^{\circ}C$- and $90^{\circ}C$-dried ginger showed little effect. Similar results were recapitulated in primary bone marrow-derived macrophages, further confirming that different dehydration conditions can cause significant differences in the immune-stimulating activity of ginger. Induction of ERK, p38, and JNK signaling was found to be the major underlying molecular mechanism responsible for the immunomodulatory effect of ginger. These results highlight the potential to improve the bioactivity of functional foods by selectively controlling processing conditions.

• 산경연구논집
• /
• 제11권3호
• /
• pp.39-50
• /
• 2020

Purpose: Agriculture, which is heavily influenced by climate conditions, is one of the industries most affected by climate change. In this respect, various studies on the impact of climate change on the agricultural market have been conducted. Since climate change is a long-term phenomenon for more than a decade, long-term projections of agricultural prices as well as climate variables are needed to properly analyze the impact of climate change on the agricultural market. However, these long-term price projections are often major constraints on studies of climate changes. The purpose of this study is to analyze the impacts of climate changes on the Korean onion market using ex-post analysis approach in order to avoid the difficulties of long-term price projections. Research design, data and methodology: This study develops an annual dynamic partial equilibrium model of Korean onion market. The behavioral equations of the model were estimated by OLS based on the annual data from 1988 to 2018. The modelling system is first simulated to have actual onion market conditions from 2014 to 2018 as a baseline and then compared it to the scenario assuming the climatic conditions under RCP8.5 over the same period. Scenario analyses were simulated by both comparative static and dynamic approach to evaluate the differences between the two approaches. Results: According to the empirical results, if the climate conditions under RCP8.5 were applied from 2014 to 2018, the yield of onion would increase by about 4%, and the price of onion would decrease from 3.7% to 17.4%. In addition, the average price fluctuation rate over the five years under RCP8.5 climate conditions is 56%, which is more volatile than 46% under actual climate conditions. Empirical results also show that the price decreases have been alleviated in dynamic model compared with comparative static model. Conclusions: Empirical results show that climate change is expected to increase onion yields and reduce onion prices. Therefore, the appropriate countermeasures against climate change in Korean onion market should be found in the stabilization of supply and demand for price stabilization rather than technical aspects such as the development of new varieties to increase productivity.

• Journal of Microbiology and Biotechnology
• /
• 제23권12호
• /
• pp.1664-1672
• /
• 2013

In Salmonella enterica serovar Typhimurium, many genes encoded within Salmonella pathogenicity island 1 (SPI1) are required to induce intestinal/diarrheal disease. In this study, we compared the expression of four SPI1 genes (hilA, invF, prgH, and sipC) under shaking and standing culture conditions and found that the expression of these genes was highest during the transition from the exponential to stationary phase under shaking conditions. To identify regulators associated with the stationary phase-dependent activation of SPI1, the effects of selected regulatory genes, including relA/spoT (ppGpp), luxS, ihfB, hfq, and arcA, on the expression of hilA and invF were compared under shaking conditions. Mutations in the hfq and arcA genes caused a reduction in hilA and invF expression (more than 2-fold) in the early stationary phase only, whereas the lack of ppGpp and IHF decreased hilA and invF gene expression during the entire stationary phase. We also found that hfq and arcA mutations caused a reduction of hilD expression upon entry into the stationary phase under shaking culture conditions. Taken together, these results suggest that Hfq and ArcA regulate the hilD promoter, causing an accumulation of HilD, which can trigger a stationary phase-dependent activation of SPI1 genes under shaking culture conditions.

• 한국식물병리학회:학술대회논문집
• /
• 한국식물병리학회 2005년도 한국식물병리학회 임시총회 및 춘계학술발표회
• /
• pp.87.2-88
• /
• 2005

• 한국작물학회:학술대회논문집
• /
• 한국작물학회 2005년도 국제학술회의
• /
• pp.184-185
• /
• 2005