• Journal of Biosystems Engineering
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• v.23 no.2
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• pp.105-114
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• 1998

Granule application with a boom has merits of accurate application and high field efficiency. In order to develop a boom granule applicator, aerodynamic properties of agrichemicals should be investigated. This study was accomplished to investigate aerodynamic properties of granules and factors affecting on them. The tested agrichemicals were urea, compound fertilizer (17-21-17), sand and zeolite. Basic physical properties of granules such as true density, sphericity, and arithmetic mean diameter for those materials were analyzed. Regression equations for pickup velocity (v$_{p}$) and saltation velocity (v$_{s}$) were proposed by the data transformation and the multi-regression analysis as follows : (equation omitted) where, 0< s < 1, 0< λ$_{i}$< 3, 35 < D/d$_{p}$ < 350, 1000 $_{p}$/p$_{a}$ < 2500 The range of pickup velocity of fertilizers and other agrichemicals were shown to be 10-16m/s and 9-13m/s, respectively. The saltation velocity of fertilizer and other agrichemicals were 3 m/s and 4 m/s, respectively.y.ively.y.y.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1998.12a
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• pp.62-68
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• 1998

• Korean Journal of Environmental Agriculture
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• v.12 no.1
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• pp.81-84
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• 1993

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.2
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• pp.217-224
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• 2009

This study investigated the effect of agrichemicals (A) and low-agrichemicals (LA) during cultivation on the quality characteristics of minimally processed lettuce (Lactuca sativa L.) during storage at $4{\pm}1^{\circ}C$. After 10 days of storage, the sugar content analysis showed that LA-treated lettuce ($4.57^{\circ}Brix$) was higher than A-treated lettuce ($3.57^{\circ}Brix$). The major minerals were K, P and Na, and mineral contents were high in A-treated lettuce during 0, 5 and 10 days. However, the sample with LA treatment had higher chlorophyll and vitamin C contents compared with A-treated lettuce. The degree of color was more stable in samples kept at LA treatment than those kept at A treatment. The polyphenol oxidase (PPO) activity of the LA-treated lettuce was 475.90 unit/g, while the A-treated sample had almost 1.5-fold higher activity. The detection of 48 residual pesticides in samples were not detected on storage 0 day.

• Journal of Biosystems Engineering
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• v.26 no.2
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• pp.93-104
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• 2001

A linear chemigation system, integrating agrichemical appication units of pesticide and fertilizer into an irrigation system, was selected as a suitable model for the cost savings in farm management and automation. Technical designs were conducted in the areas of structure, power, drive, control, and hydraulic systems. An experimental farm was sectioned into the fields of 40m by 200m and systemized with the linear-move chemigation system of 36m in span. The chemigation system consisted of a base unit monitoring and controlling overall operation, and a driving unit traveling linearly and injecting agrichemicals. Monitoring and interlocking systems were utilized against unexpected malfunctions of power, injection and drive systems using radio freuency modems between the units. The system can be also modified to various farm sizes and stationary systems of indoor and outdoor.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.10a
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• pp.623-626
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• 2007

본 논문에서는 유비쿼터스 환경에서의 친환경 웰빙문화에 대한 소비자의 욕구를 충족 시킬 수 있는 단거리 통신 휴대 단말형 잔류농약 검출 시스템을 제안한다. 또한, 제안 시스템의 구성 및 개발을 위한 핵심 기술 사항에 관하여 기술하고 활용 가능한 응용분야에 관하여 소개하고자 한다.

• Journal of Aerospace System Engineering
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• v.4 no.1
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• pp.15-18
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• 2010

In the hot summer manual spray work for plants would be the hardest one among the agricultural field works. Besides the physical load the possible toxication would strongly ask a way to do the job on behalf of human. Although an aircraft with sprayer could be a good candidate, the manned airplanes do not play proper roles in our country because of field geometry. Today, unmanned helicopter as expensive as 200,000 dollars can do the job with high risk of control. Therefore safe and cheap air vehicle with sprayer, if developed, could be a great help to agriculture.

• Korean Journal of Environmental Agriculture
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• v.28 no.4
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• pp.435-441
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• 2009

In the present study, we analyzed the defensin protein deduced from Korean radish (Raphanus sativus L.) seeds.To express the genes in E. coli, we constructed a recombinant expression vector with a defensin gene, named rKRs-AFP gene isolated from Korean radish seeds. Over expressed rKRs-AFP proteins was separated by SDS-PAGE to determine the purity, and protein concentration was determined by the Bradford method. Antifungal activity was assessed by disk assay method against the tested fungi. As a result, when 500 mL of cell culture were disrupted by sonicator, 32.5 mg total proteins were obtained. The purified protein showed a single band on SDS-PAGE with estimated molecular weight about 6 KDa, consistent with the molecular mass calculated from the deduced amino acid sequence. The purified rKRs-AFP protein showed remarkable antifungal activities against several fungi including Aspergillus niger, Botrytis cinerea causing the gray mold disease, and Candida albicans. In field tests using the purified rKRs-AFP protein, the protein showed the reducing activity of disease spot and the mitigating effect of spreading of disease like agrichemicals. The immuno-assay of rKRs-AFP protein showed that the purified protein entirely accumulated at B. cinerea cytoplasm through the hyphal septa shown by fluorescence imaging. There was no fluorescence inside the cell, when the hypha was incubated without the protein. These all results indicate that the recombinant rKRs-AFP proteins can be utilized as a potential antifungal drug to control harmful plant fungal pathogens.

• Journal of Korean Society on Water Environment
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• v.25 no.1
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• pp.84-89
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• 2009

Our nation's water resources remain susceptible to contamination by phenolic agrichemicals. These compounds can be toxic to a variety of organisms including humans. Their disposal is restricted in many countries with strict limits for acceptable concentrations in drinking water. Enzyme-mediated in situ stabilization has been advocated as an approach for the treatment of phenolic compounds in soils and groundwater. This study reports the development of a new approach to quantify the activity of the HRP enzyme in aqueous systems. The method is based on the coupled processes of energy transfer and enhanced chemiluminescence using a luminol-$H_2O_2$-HRP system. In this study, the effects of solution pH, ionic strength and aqueous concentrations of HRP, $H_2O_2$ and enhancer were evaluated on the p-iodophenol-enhanced, HRP-catalyzed chemiluminescence reaction intensity in Tris-HCl buffer. All assay components were found to affect the maximum chemiluminescene intensity. The calibration curve for HRP showed the linear relationship with maximum light intensity.

• Culinary science and hospitality research
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• v.13 no.4
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• pp.243-255
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• 2007

This study carried out a survey which is related to food safety in food business in order to find out interest in food safety and to get awareness of food safety in food business. The research was done through surveys for the people in the Seoul Metropolitan area. 232 out of 250 answers were used in analyzing frequency, factor, $x^2$-test, and t-test through SPSS Win 12.0. There are three main factors of food safety in food business. The first is food borne illness(65.9%), the second is trans-fat(63.4%), and the third is remained agrichemicals(58.5%). Basically, women consider food safety more seriously than men do, and married women than unmarried women. Women were unsatisfied with the government's regulations than men were, married women than unmarried women. Women more consider awareness of food safety than men do, married women than unmarried women. Overall, unmarried women worried about their eating stuff seriously than any other group does. People consider food safety first, more and more these days, therefore, we need special management programs and regulations to focus on food safety and to support many studies about food safety.