• The Korean Journal of Community Living Science
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• v.17 no.2
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• pp.125-138
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• 2006

While the global food system prevails in America, the community food system is also spreading rapidly. The former, which is based on industrial agriculture, has negative impacts on family farms, food safety, and community development. In contrast, the latter has positive effects on farmers, consumers, communities, and the environment. Community food systems have been able to grow successfully through the participation of farmers and consumers, support of the federal and state governments, and the initiatives of NGOs. Food Circle, upon which this study focuses, is one of the community food systems based on the regional level. It is the outcome of the green movement in Kansas City, Missouri. The goal of Food Circle in Missouri is to retain and support rural family farms by connecting them with regional consumers. Its main activity is to collect data, including a directory of farmers and their regional products, and distribute this data to regional consumers. It is informally organized and entirely self funded. Although community food systems have several problems, their development is to continue in America. The food system in Korea has become a global one in recent decades, and agricultural problems and food safety issues are being generated as a result. The development of community food systems would be helpful in resolving these problems. In order to activate community food systems in Korea as seen in America's case, it would be necessary to have the imperative participation of both farmers and consumers, the support of the central and provincial governments, and the initiatives of NGOs.

• Journal of the Korean Society for Precision Engineering
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• v.27 no.12
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• pp.41-47
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• 2010

There are many unbalanced models such as helicopter's rotor blades, small-sized precision motor in industrial applications. In the real products, their gravity center usually does not accord with the desired gravity center. If the deviation is large between them, it can be a major cause of vibration and noise as the part of model rotate. Therefore the gravity center in the rotational parts should be controlled properly because of static and dynamic balancing of the parts. In the research, the rotor blade of unmanned helicopter has been selected to obtain the high quality of balancing. In order to achieve the purpose, measuring system has been developed. In the system applied principle is three point weighting method, which is one of the Multiple-point Weighting Method. It has circle fitting for compensation of machining error, after measuring the values. From this study, the results showed that the proposed measurement procedure gives reliable and precise gravity center.

• Korean Journal of Pharmacognosy
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• v.37 no.1 s.144
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• pp.16-20
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• 2006

The protective effects of the aqueous MeOH extracts of stem and root Acanthopanax koreanum Nakai against oxidative stress were investigated. Anti-oxidant activity of the stem extract of A. koreanum was observed in the DPPH free radical scavenging $(IC_{50}=58.7\;{\mu}g/ml)$ and the SOD test $(IC_{50}=17.52\;{\mu}g/ml)$. According to data analysis of cell survival ratio of normal fibroblasts, the skin irritation by both extracts from A. koreanum was concerned. However, in the skin primary parch test, both extracts obtained Grade I, which means that there was no skin irritation. After induction of oxidative irritation, cell survival ratio of normal fibroblasts was also monitored and it turned out that stress-inducing group with both extracts had more increased cell survival ratio. The cell extension of the stress-inducing group treated with the stem extract was most dominant in morphological study. Based on these results, the stem extract of A. koreanum showed the protective effect against oxidative stress on normal fibroblast.

• Applied Chemistry for Engineering
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• v.1 no.2
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• pp.232-239
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• 1990

${\gamma}$-Glycidoxy propyl trimethoxy slilane, CTBN rubber(carboxyl terminated butadiene acrylonitrile rubber) and GMA(glycidyl methacrylate) were reacted with the surface of silica one by one in existence of TEA(triethylamine) or BPO(benzoyl peroxide). The amount of reactant was 2.5~5.8% of treated silica weight. The treated silica was mixed with epoxy resin and MTHPA(methyltetrahydrophthalic anhydride) in the range of 0~60% (wt. %) of total component. The flexural and thermal properties were tested for cured products. In filler content 35~55%, the using of silica treated with silane/rubber or silane/rubber/vinyl represented 25% higher flexural strength, 5% lower flexural modulus and 13% higher than mixing liquid rubber 3% with epoxy resin containing untreated silica.

• Korean Journal of Organic Agriculture
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• v.20 no.1
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• pp.91-99
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• 2012

This study was conducted to develop a functional feed additive for pig with spent $Lycium$ $chinense$ Mill fruit. We investigated the optimum conditions for the extraction of polyphenol from spent $Lycium$ $chinense$ Mill using methanol. Methanol concentration as a solvent for extraction, extraction time and the volume of solvent per a gram of solid (ground spent Lyceum chinense Mill) were selected as parameters. Three levels of parameters were configured according to Box Behnken experiment design, a fractional factorial design, and total 15 trials were employed. Total polyphenol concentration from each trial was used as response from experiment system and effects of parameters on total polyphenol extraction efficiency were determined using response surface model. As a result, all terms in analysis of variance, regression ($p$ = 0.001), linear ($p$ = 0.002), square ($p$ = 0.017) and interaction ($p$ = 0.047) was significant and adjusted determination coefficient ($R^2$) was 94.7%. Total polyphenol extraction efficiency was elevated along increased methanol content and decreased solvent to solid ratio. However extraction time did not affect the efficiency. This study provides a primary information for the optimum extraction conditions to maximize total polyphenol recovery from spent Lycium chinens Mill fruit and this result could be applied to re-use of argo-industrial by-products and to develop of functional feed additives in organic farming.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.24 no.3
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• pp.272-280
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• 2014

Objectives: The purpose of this study was to evaluate the characteristics of worker exposure to hazardous chemical substances and propose the direction of work environment management for protecting worker's health in the semiconductor assembly process. Methods: Four assembly lines at two semiconductor manufacturing companies were selected for this study. We investigated the types of chemicals that were used and generated during the assembly process, and evaluated the workers' exposure levels to hazardous chemicals such as benzene and formaldehyde and the current work environment management in the semiconductor assembly process. Results: Most of the chemicals used at the assembly process are complex mixtures with high molecular weight such as adhesives and epoxy molding compounds(EMCs). These complex mixtures are stable when they are used at room temperature. However workers can be exposed to volatile organic compounds(VOCs) such as benzene and formaldehyde when they are used at high temperature over $100^{\circ}C$. The concentration levels of benzene and formaldehyde in chip molding process were higher than other processes. The reason was that by-products were generated during the mold process due to thermal decomposition of EMC and machine cleaner at the process temperature($180^{\circ}C$). Conclusions: Most of the employees working at semiconductor assembly process are exposed directly or indirectly to various chemicals. Although the concentration levels are very lower than occupational exposure limits, workers can be exposed to carcinogens such as benzene and formaldehyde. Therefore, workers employed in the semiconductor assembly process should be informed of these exposure characteristics.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.198-198
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• 2011

Organocatalysis is a relatively new and popular area within the field of chiral molecule synthesis. It is one of the main branches of enantioselective synthesis with enzymatic and organometallic catalysis. In recent years, immense high quality studies on catalysis by chiral secondary amines were reported. These progresses instantly led to different organocatalytic activation concepts, so thousands of researchers from academia and the chemical industry are currently involved in this field and new ideas, new approaches, and creative thinking have been rapidly emerged. Organocatalysts, some of which are natural products, appear to solve the problems of metal catalysts. Compared to metal-based catalysis, they have many advantages including savings in cost, time, and energy, easier experimental procedure, and reduction of chemical waste. These benefits originate from the following factors. First, organocatalysts are generally stable in oxygen and water in the atmosphere, there is no need for special equipments or experimental techniques to operate under anhydrous or anaerobic conditions. Second, organic reagents are naturally available from biological materials as single enantiomers that they are easy and cheap to prepare which makes them suitable for small-scale to industrial-scale reactions. Third, in terms of safety related catalysis, small organic molecules are non-toxic and environmentally friendly. Therefore, the purpose of this research is to develop novel synthetic methods and design for various organocatalyst. Furthermore, it is expected that these organocatalysts can be applied to a variety of asymmetric reactions and study the transition state of these reactions using a metal sulface. Here, we report the synthesis of unprecedented organocatalysts, proline and pyrrolidine derivatives with quaternary carbon center.

• Journal of Animal Science and Technology
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• v.54 no.3
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• pp.191-198
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• 2012

The objective of this study was to evaluate the potential use of a dielectric barrier discharge (DBD) plasma system to improve microbial safety of sliced cheese. The atmospheric pressure plasma (APP) effect on visual appearance and a sensory evaluation were also carried out. The number of Escherichia coli inoculated on cheese slices decreased by 0.09, 0.47, 1.16 and 1.47 log cycles with helium (4 liters/min [lpm]) and 0.05, 0.87, 1.89 and 1.98 log cycles with He/$O_2$ mixture (4 lpm/15 standard cubic centimeters per minute), after being treated with plasma for 1, 5, 10, and 15 min, respectively. Significant reductions were also observed in Staphylococcus aureus inoculated onto cheese slices ranging from 0.05 to 0.45 log cycles with He and from 0.08 to 0.91 log cycles with He/$O_2$-treated samples, respectively. Adding oxygen resulted in a significant increase in inactivation of both pathogens. No visible change in the plasma-treated cheese slices was observed even though the instrumental analysis showed a significant decrease in the $L^*$-value and an increase in the $b^*$-value. The cheese slices were damaged after 10 and 15 min of plasma treatment. In addition, significant reductions in sensory quality including flavor, odor, and acceptability of plasma-treated cheese slices were observed. The results indicate that the DBD plasma system has potential for use in sanitizing food products, although the effect was limited. Further development of the APP system is necessary for industrial use.

• Archives of design research
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• v.15 no.1
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• pp.407-414
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• 2002

Human does information processing more efficiently using mental model at his understanding process. if We know what mental model is, we will know how to percept that. Similarly is it used visual mental model to percept visual object\ulcorner If it is true, we will analysis how man to understand. In this research, we have one experimentation to timid out that is true. So we did experimentation to know how man to understand new products by visual mental model. So we use 2700cc car's side view as stimuli. To A Subjects, we give them to see re\ulcorner size view before 120% ratio. To B Subject, we give them to see 120% ratio. After a experimentation, It is true that we make hypothesis that A Subjects percept this stimuli too long then B Subjects. Accordingly it proves human to use visual mental model to percept visual object. The result of experimentation, a testee use preliminary stimulus as basis of evaluation. It means that he use mental model as basis of evaluation of main stimulus. Accordingly development of new design can afford more strategic approach. Industrial designer who want to strategic approach can forced on high-weighted form attribute as consumer gives.

• Applied Chemistry for Engineering
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• v.23 no.4
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• pp.416-420
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• 2012

A convenient procedure for the synthesis of fatty acid diesters was studied. Long chain diesters have been used as biolubricant and transformer oils. The series of octyl, dodecyl, hexadecyl, octadecyl, and octadec-9-enyl glycidyl ether were used to synthesize those diesters. Alkyl glycidyl ethers were reacted with fatty acid such as oleic acid and octanoic acid, and octanoic acid. The one-step / two-step reactions were compared during the condensation reaction. The products were confirmed by $^{1}H-NMR$, FT-IR, and HR/MS spectra. The yield of the product 1-O-acyl-2-O, 3-O-dioctadec-9-enoylglycerol was 55~60%.