• Journal of Food Hygiene and Safety
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• v.26 no.4
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• pp.383-387
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• 2011

The levels of migration of 1-hexene and 1-octene residues in PE (polyethylene) products were analyzed by Headspace gaschromatography (HSGC). A total of 21 samples were including lap, polyglove, zipper bag and ect. The samples were eluted with distilled water, 4% acetic acid, 20% ethanol and n-heptan. The limit of detection (LOD) was 0.06 mg/L ~ 0.30 mg/L and limit of quantitation (LOQ) was 0.21 mg/L ~ 1.01 mg/L, respectively. But because of the high volatile, n-heptan elution was not detected 1-hexene and 1-octene standard. 1-hexene and 1-octene were not detected in the sample which eluted with simulant at $60^{\circ}C$, 30min. Microwave for 1 minute also treated sample and direct heated at $100^{\circ}C$ without simulant were not detected.

• Composites Research
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• v.14 no.2
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• pp.13-21
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• 2001

Substituting composite structures for conventional metallic structures has many advantages because of higher specific stiffness and specific strength of composite materials. In this work, one-piece driveshafts composed of carbon/epoxy and glass/epoxy composites were designed and manufactured for a rear wheel drive automobile satisfying three design specifications, such as static torque transmission capability, torsional buckling and the fundamental natural bending frequency. Single lap adhesive joint was used to join the composite shaft and the aluminum yoke. The torque transmission capability of the adhesively bonded composite shaft was calculated with respect to bonding length and yoke thickness by finite element analysis and compared with the experimental result. Torque transmission capability was based on the Tsai-Wu failure index fur composite shaft and the failure model which incorporated the nonlinear mechanical behavior of aluminum yoke and epoxy adhesive. From the experiments and the finite element analyses, it was found that the static torque transmission capability of the composite driveshaft was highest at the critical yoke thickness, and saturated beyond the critical length. Also, it was found that the one-piece composite driveshaft had 40% weight saving effect compared with a conventional two-piece steel driveshaft.

• Fire Science and Engineering
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• v.27 no.2
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• pp.46-53
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• 2013

The architecture environment has changed. The corresponding design criteria should be changed. From July 27th, 2005 the Korea Standard of the fire door changed concerning the smoke resistance test which made the door gap structure more elaborate. However the National Fire Safety Codes are applied by the old data's of England. Which in case differs in the actual construction to the blue print, making the safety standard too excessive. Analyze the results and the phenomenon that occurs due to the difference between design and reality. The National Fire Safety Codes should be revised to leakage crack calculation is presented. Difference of the air flow for the smoke protection due to the stack effect analyzed. Living patterns and evacuation patterns of the apartment reflect and reasonable air flow measurement method are presented.

• Journal of Periodontal and Implant Science
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• v.28 no.4
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• pp.677-692
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• 1998

In order to study the effects of cigarette smoking on periodontal tissue, gingival fibroblast from the smoking and nonsmoking groups were cultured and each group were treated with nicotine(50ng/ml,100ng/ml) and NNK(50ng/ml, 100ng/ml) to test their attachment ability at time intervals of 30minutes, 60minutes, 90minutes, 120minutes, and 240minutes. Using the same method, the growth each group treated with nicotine and NNK in order to compare their attachment ability and growth rate was done. The Results are as follows. 1. In comparing the attachment ability and growth rate between the smoking and non-smoking group were significantly higher in all time intervals. 2. When the attachment ability was com-pared among these two groups after treatment with nicotine and NNK, the non-smoking group showed decrease in attachment ability while the smoking group was not affected. 3. The growth rate of these two groups were compared after treating with nicotine and NNK. The growth rate of fibroblast from the non-smoking group decreased while fibroblast from the smoking group was not affected. These results suggest that fibroblast from the non-smoking group showed higher attachment ability, growth rate, and sensitivity to nicotine and NNK. This implies that fibroblast from the non-smoking group is a more reliable source in testing the cytotoxicity of nicotine and NNK. Also it could be reasonable to think that nicotine and NNK is a probable cause for problems in attachment and repair mechanism.

• Journal of Food Hygiene and Safety
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• v.29 no.3
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• pp.241-247
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• 2014

In this study, HPLC-RI was used to determine sugars and sugar alcohols contents in 102 different kinds of processed foods met to children's taste. The average amount of sugars per 100 g of candies was 70.25 g, of processed cocoa products was 65.34 g, of processed chocolate products was 47.53 g, of breads was 25.66 g, of cookies was 22.28 g, of ices was 12.47 g, of snacks was 9.74 g. Processed cocoa product items had relatively higher sucrose contents (56.80 g/100 g) than any other items. The average amount of sucrose per 100 g of candies was 44.20 g, of processed chocolate products was 32.89 g, of breads was 23.11 g. When the contents of sugars in processed foods met to children's taste per on serving size were compared to WHO guidelines, the percentages were 5.84~28.52 about recommended daily intake of total sugar of 50 g. The result for the analysis of confectioneries showed that 13 samples of 102 were detected and the sugar alcohols content of samples investigated varied between 0.01~15.06%.

• Journal of Korean Library and Information Science Society
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• v.49 no.1
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• pp.1-22
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• 2018

The general or separate reading room in domestic public libraries is a space that represents Korea's unique characteristics that are rarely found in advanced cultural countries. If it is an indispensable space for residents of the community, all public libraries should install and operate it. Otherwise, the general reading room of existing public libraries should be reduced or improved and the new library needs strategic thinking about its installation. Therefore, this study analysed the operation status and major issues of the general reading room, and then suggested the direction based on the survey and comparison of the recognition of the general reading room for the staff (librarian) and the users. The results can contribute not only to the ongoing debate on the general reading room, which is the central theme of discussion of local public goods, but also to find desirable alternatives.

• Journal of Korean Library and Information Science Society
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• v.45 no.2
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• pp.29-50
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• 2014

The goal of this study is to review the importance and to prove the feasibility of establishment and operation of the academic collaborative repositories in Korea. To that end, its importance was analyzed from the sides of collection space of libraries, national management of academic information resources, cases of collaborative repository. And its feasibility was logically proved in terms of the global production and distribution of knowledge and information, library relevant laws, national policies of academic information resources, and actual collection space of academic libraries. As a result, the importances and feasibilities of establishment of the academic collaborative repository were revealed by enough. Accordingly, there is a need to develop immediately the establishment and operation model of the collaborative repository for academic libraries.

• Journal of the Korean Chemical Society
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• v.34 no.2
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• pp.189-196
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• 1990

8-Acyl-2-hydroxyphenazine-5,10-dioxides and 8-acyl-2-aminophenazine-5,10-dioxides were synthesized by the reaction of hydroquinone and 4-aminophenol with 6-acylbenzofuroxans which had been obtained from acetanilide and n-acyl chlorides bearing butanoyl, hexanoyl and octanoyl groups. The antimicrobial activities of these phenazine dioxide derivatives were investigated in terms of minimum inhibitory concentration by the common twofold dilution technique. It was observed that the antimicrobial activity of the phenazine dioxide derivatives bearing octanoyl group was stronger than that of those bearing butanoyl and hexanoyl groups in gram positive microorgamisms, but it was observed that the antimicrobial activity and the number of the carbon atom of acyl groups did not have any relation in gram negative microorganisms. When the activity of xanthine oxidase which is the key enzyme in the generation of superoxide anion radical ($O_2^-$), was measured in the presence of phenazine dioxide derivatives, the inhibitory action of the enzyme activity of 8-acyl-2-hydroxyphenazine-5,10-dioxides was increased in accordance with the number of the carbon atom of acyl groups.

• Korean Journal of Food Science and Technology
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• v.17 no.2
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• pp.81-88
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• 1985

A potential lipid producing strain of Penicillium sp. was isolated from natural source. Penicillium sp. was cultivated in an appropriate medium containing 6% of glucose as a corbon source, ammonium nitrate as a nitrogen source, C:N ratio 200, pH 4.0 for a period of 17 days at $35^{\circ}C$. Under the condition, the lipid content was 64.2% of dry cell weight. The total lipid produced was 13.7g/100g of glucose consumed. The proportion of nonpolar and polar lipid fractions was 92.2% and 7.8%, respectively. The nonpolar lipid compositions of lipid produced under optimum condition were 5.3% of free fatty acids, 6.8% of free sterols, 9.3% of partial glycerides and 72.0% of triglycerides. The major fatty acids of total lipid were 20.1% of palmitic acid, 21.6% of linoleic acid and 53.3% of oleic acid.

• Journal of Information Management
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• v.42 no.4
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• pp.175-194
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• 2011

This study evaluated the fiction collection of Korean public libraries by applying use factor and suggested various measures to enhance collection development function. As a result, while the collection building and borrowing ratios of Korean literature in literature collection by language were the highest at 62.6% and 54.3% respectively, the use factor was lower than the base value(1.00). And while the collection building and borrowing ratios of Korean contemporary fiction by item category were the highest at 65.60% and 51.36% respectively, the use factor was lower than the base value and the use factor by year is decreasing in recent years. The reason is because of poor collection development. Therefore, public library need to consider active alternatives such as establishment of the collection development policy and fiction collection development guideline, composition of the fiction material selection committee, adaption of the dedicated librarian system for fiction material development, development and utilization of a selection tool for fiction materials, and periodic evaluation of fiction collection.