• International Journal of Industrial Entomology and Biomaterials
• /
• v.8 no.2
• /
• pp.135-138
• /
• 2004

In order to find potential anticancer agents, we extracted pheophytin from silkworm feces according to various dry and storage methods such as sun dry, shade dry, fresh freezing dry and freezing dry after freezing storage (for 1∼3 years). The pheophytin extracts, mainly 10-hydroxypheophytin a, little b, of various storage silkworm feces were analyzed by reversed-phase high-performance liquid chromatography with photodiode array and fluorescence detection. The content of those pheophytih in old silkworm for 3 years (freezing storage and freezing dried in use, or freezing dried and cold storage) was better than others. The cytotoxicity of the pheophytin extracts and ethanol extracts of various storage silkworm feces were measured using Jurkat cells originated from human leukemia, using dye uptake assay (MTT) in order to find effective photodynamic therapeutic agents. The anticancer activity of those pheophytin extracts in various storage methods showed little difference among them. But ethanol extracts of fresh freezing dried silkworm in the current year was good cytotoxic activity than those of any other silkworm feces. With regards to these results, fresh ethanol extracts of silkworm feces were better than old ones. On the other hands, the pheophytin extracts of old silkworm feces contained the highest percentage of pheophytin content and showed good cytotoxicity against cancer cells by changing the pheophytin into pheophobide in the degradative process.

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 2000.11c
• /
• pp.811-818
• /
• 2000

Agricultural chemicals spraying is one of the most efficient methods for pesticides control. General farming groups use Speed Sprayer but its deposition amount on practical crops is only 20% of total amount in SS case. Agricultural chemicals which fail to arrive the crops not only cause environmental contamination but loss of agriculture chemicals by lower deposition efficiency. For the purpose of improvement of these problems, this experiment proposes SS attachment type electrostatic induction spraying apparatus with DC power which improves deposition efficiency of agriculture chemicals on the crops.

• Proceedings of the Korean Society of Plant Biotechnology Conference
• /
• 2003.10a
• /
• pp.131-131
• /
• 2003

• Journal of Biosystems Engineering
• /
• v.29 no.6 s.107
• /
• pp.544-552
• /
• 2004

This study was conducted to suggest the efficient gathering and recycling method of disused agricultural machinery in rural environment. In order to suggest this methods, the keeping means, maintenance, disused period and kinds of agricultural machinery were investigated. The results obtained in this study were as follows : The disused agricultural machinery have been leaved on the vacant lot of a farmhouse and an around field for $2\~5\;years$. The leaving reason of the disused agricultural machinery was low interesting and gathering price for the disused agricultural machinery. The present situation for recycling method was using as a scrap iron, however to increase recycling percent the disassembling process has to divide as using and parts concretely. And the design of agricultural machinery was considered the easiness of a disassemble and assemble the agricultural machinery. To manage and supply efficiently for the second-hand parts of agricultural machinery need to the establishment of circulation information center and internet site for the parts.

• Korean Journal of Soil Science and Fertilizer
• /
• v.42 no.3
• /
• pp.192-200
• /
• 2009

Soil testing is one of the best management practices for sustainable agriculture. Recently, as increasing soil testing needs, simplification of soil analytical procedure has been required. To determine recommendable multi-element extractant, the soil testing results of available phosphate and exchangeable cations between the conventional methods (Lancaster and 1M $NH_4OAc) and multi-element extraction methods such as Mehlich III, Modified Morgan and Kelowna methods were compared. There were highly significant correlation between the conventional methods and multi-element extraction methods (Mehlich III, Modified Morgan and Kelowna) for available phosphate and exchangeable K, Ca, Mg and Na. The coefficients of determination ($R^2) between available phosphate extracted by Lancaster method and multielement extraction methods were in the order of Mehlich III ($0.979^{***}$) > Kelowna ($0.977^{***}$) > Modified(Mod.). Morgan ($0.553^{***}$). For exchangeable cations, there were highly significant correlations between 1M $NH_4OAc method and Mehlich III, Mod. Morgan and Kelowna. However, exchangeable K, Ca and Mg by Mehlich III method were more highly correlated with conventional method than other methods. Therefore, Mehlich III extraction method could be recommended as a single extractant for simultaneous measurement using ICP in the analysis of avaliable phosphate and exchangeable cations.

• Proceedings of the Korean Society for Bio-Environment Control Conference
• /
• 2005.05a
• /
• pp.125-130
• /
• 2005

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2005.04a
• /
• pp.80-81
• /
• 2005

• Proceedings of the Korean Society for Bio-Environment Control Conference
• /
• 2006.05a
• /
• pp.186-191
• /
• 2006

• 한국약용작물학회:학술대회논문집
• /
• 2009.05a
• /
• pp.147-148
• /
• 2009

• Korean Journal of Agricultural Science
• /
• v.43 no.4
• /
• pp.507-521
• /
• 2016

Landslides are one of the most common natural hazards causing significant damage and casualties every year. In Korea, the increasing trend in landslide occurrence in recent decades, caused by climate change, has set off an alarm for researchers to find more reliable methods for landslide prediction. Therefore, an accurate landslide-susceptibility assessment is fundamental for preventing landslides and minimizing damages. However, analyzing the stability of a natural slope is not an easy task because it depends on numerous factors such as those related to vegetation, soil properties, soil moisture distribution, the amount and duration of rainfall, earthquakes, etc. A variety of different methods and techniques for evaluating landslide susceptibility have been proposed, but up to now no specific method or technique has been accepted as the standard method because it is very difficult to assess different methods with entirely different intrinsic and extrinsic data. Landslide prediction methods can fall into three categories: empirical, statistical, and physical approaches. This paper reviews previous research and surveys three groups of landslide prediction methods.