• Journal of Dental Rehabilitation and Applied Science
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• v.31 no.4
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• pp.329-339
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• 2015

Purpose: To investigate the information acquisition, selection criteria and selection methods of Mongolian dentists regarding adhesive agents for bonded restorations, and to provide future direction for continuing education. Materials and Methods: One hundred Mongolian dentists were interviewed and asked to complete a questionnaire containing 7 questions on general information about the responder, 8 questions on information acquisition and selection of bonded restoration agents, and 10 questions on continuing education. Results: Objective and credible information regarding bonded restoration materials were not being acquired, and logical material selection was not being made. The extent of continuing education was inadequate and not enough information regarding education was being acquired. The participants responded positively to online supplementary education. Conclusion: A systemized approach needs to be established in Mongolian dentistry to enable organized delivery of evidence-based guidelines and information, and logical selection of the numerous and various bonded restoration agents. Furthermore, the education of dentists, through various means, is required to enable proper use of the selected materials.

• Journal of the Korean Home Economics Association
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• v.41 no.10 s.188
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• pp.101-116
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• 2003

The study was conducted to establish hygienic standards of salad items for pizza restaurant located in Seoul by applying HACCP system during the summer of 2000. The study measured temperature, time, pH, Aw and microbial assessments. The hygienic conditions of the kitchen and workers were on the average(1.21, 1.0 out of 3 pts.), but some improvement should be made: separate use of trash can and leftover disposal, separate use of knives and cutting boards, habits for hand washing and wearing hygienic gloves. For salad production, all procedures were peformed under food safety danger zone ($5{\~}60^{\circ}C$). The ingredients were mostly above pH 5.0 and high in Aw($0.94{\~}0.99$). Microbial assessments for salad production revealed that TPC($1.8{\times}10^3{\~}1.0{\times}10^{10}CFU/g$) and coliforms($1.5{\times}10{\~}5.2{\times}10^5 CFU/g$) exceeded the standards by Solberg et al.(TPC: $10^6CFU/g$, coliforms: $10^3CFU/g$). S. aureus was not detected but Salmonella was found in three food items(egg, macaroni and macaroni salad). Moreover, the workers' hands contained 3.1 104 CFU/g of TPC and 4.2 102 CFU/g of S. aureus requiring further remedy since it exceeded the safety standards suggested by Harrigan and McCance (500 CFU/g of TPC per $100cm^2$ and 10 CFU/g of coliforms per $100cm^2$). According to the critical control point(CCP) decision tree analysis, vegetable receiving, vegetable holding, mixing, display on coleslaw, macaroni draining, display on macaroni salad, egg peeling & cutting, apple cutting, and display on salad bar were determined as CCPs. From the findings it would be suggested that purchase of Quality materials, short holding and display time, storing food at right temperature, using sanitary cooking utensils, and improvement of workers' food handing practices are needed to ensure the safe salad production in this specific pizza restaurant.

• Journal of Dental Rehabilitation and Applied Science
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• v.33 no.2
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• pp.80-87
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• 2017

Purpose: The aim of this study was to assess the physical properties of a novel resin-based endodontic sealer, Any-Seal, in comparison with AH Plus Jet. Materials and Methods: Flow, radiopacity and compressive strength were examined according to ISO 6876/2001. For flow test, 0.05 mL of sealer was placed between glass plate and 100 g weight were applied. Ten minutes after mixing the sealers, the load was removed and the diameters of the compressed sealer discs were measured. For radiopacity, 10 mm diameter and 1 mm thickness sample were fabricated and took radiograph with an aluminum step-wedge and analyzed using imaging program. For compressive strength test, $4mm{\times}6mm$ cylindrical specimen was fabricated and tested after 24 hours and 1 week using Universal testing machine. Results: Both tested sealers were consistent with ISO 6876/2001 in the flow and radiopacity test. The flow values of both sealers were not significantly different (P > 0.05). AH Plus Jet had significantly higher radiopacity (P < 0.05). AH Plus Jet showed higher compressive strength at both time intervals (P < 0.05). Conclusion: Any-Seal showed low compressive strength until after 1 week, so its physical and biological aspect should be evaluated more before clinical use.

• Korean Journal of Environmental Agriculture
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• v.17 no.3
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• pp.200-204
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• 1998

Physical and chemical properties of artificial soil produced by firing process were analyzed and compared with normal dry field soil and soil quality standards. Material used for production was water and wastewater treatment sludge, chabizite, and lime. The mixed material was thermally treated in the firing kiln at about $300^{\circ}C$ and $1,000^{\circ}C$, respectively, as per designed process. General properties of the artificial soil were classified as sand by unified soil classification method and similar to the dry-field soil, and even soil conditioning effect were expected when it is mixed properly with normal soil. The artificial soil is high in pH and permeability compared to the dry-field soil. Heavy metal concentrations of the artificial soil met the soil quality standards for the farmland. Overall, the artificial soil was thought to be an appropriate soil which can be returned safely to the nature without significant adverse effect. The cost for the artificial soil production process needs to be lowered for practical application as a sludge treatment, therefore, commercializing of the artificial soil is under review.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.8
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• pp.287-297
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• 2020

This study examined ways of improving the internal insulation performance of aging university buildings, and to enhance the convenience of occupants in university buildings and the insulation effect of aging buildings. This research was conducted to solve the problem of continuous requests for improving the insulation performance of office workers in the Nehemiah Hall building of Handong University. The results showed that the internal temperature of Nehemiah Hall was low compared to the internal temperature of the adjacent building. Considering the characteristics of the building, the university chose insulating materials under the theme of internal insulation. The experiment was conducted by installing internal wall insulation used in the market by producing a model room that miniaturized the university professor's office. Based on the experimental results, an economic evaluation was conducted to analyze the insulation effect by measuring the heating time and actual heat transmission coefficient. An economic evaluation was conducted by experiment and theory and on a winter and summer basis. According to the research, when an Isopink (30 T) was introduced as an internal insulation material in 60 offices of Nehemiah Hall, it could save up to 1,071,600 won in total during the winter season and 109,200 won during the summer season.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.50-50
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• 2018

최근 생태 조경용 관상식물의 수요가 증가함에 따라, 환경적응성이 강하며 관상용으로 가치가 있는 자생식물들을 개발하기 위한 노력이 증가하고 있다. 둥근산꼬리풀(Veronica rotunda Nakai)은 화기가 길며, 꽃이 만개하였을 때 관상가치가 높아 정원의 지피식물 및 실내 분화식물로 이용 가치가 높다. 본 연구는 둥근산꼬리풀의 육묘기술을 개발하기 위하여 2018년 5월 8일에서 6월 30일까지 약 8주간 시행되었다. 본 연구의 공통사항은 200구 트레이에 원예상토를 충진한 후 셀당 4립씩 종자를 파종하였다. 이후 무차광 조건에서 육묘하였으며, 추비는 hyponex $500mg{\cdot}L^{-1}$를 잎이 충분히 젖도록 2, 4주차에 엽면시비 하였다. 파종 용기별 실험은 162, 200, 288구 트레이를 사용하였고, 파종립수별 생육을 알아보기 위하여 200구 트레이에 셀 당 1, 2, 4 및 6립을 파종하였다. 토양종류는 원예상토, 피트모스:펄라이트(3:1, 4:1)의 혼용토를 육묘에 이용하였다. 각 혼용토의 비료 농도는 한아름상토(N:P:K, $300-200-200mg{\cdot}L^{-1}$)를 기준으로 0, 100 및 200%로 조성하였다. 추비는 hyponex (6.5-6-19)를 물에 희석하여 0, 500, 및 $1000mg{\cdot}L^{-1}$로 파종 후 2, 4주차 총 2회 잎이 충분히 젖을 정도로 엽면시비 하였으며, 차광실험은 0, 55 및 75% 차광막이 설치된 곳에 재배하였다. 8주간 육묘 실험을 수행한 결과, 파종 용기별로는 162구 트레이에서 생육한 유묘에서 각 측정 항목별로 유의적으로 양호한 결과가 나타났다. 셀 당 파종립수 별로는 1립 파종구에서 가장 우수한 유묘의 생장을 보였으며, 파종립수가 증가할수록 생육이 감소하는 경향이 나타났다. 토양조성을 달리하였을 때 원예상토 단용 처리에서 가장 생육이 우수하였고, 피트모스가 혼합된 토양에서는 생육이 저조한 경향을 보였다. Hyponex의 농도를 달리하여 추비하였을 때 $1000mg{\cdot}L^{-1}$에서 유묘의 생육이 가장 양호하였으며, 추비농도가 감소할수록 생육이 감소하는 경향을 보였다. 차광정도에 따른 생육을 관찰한 결과 55% 차광에서 생육이 가장 우수하였고, 75% 차광의 경우에는 무차광 처리구에 비해 생육이 감소하는 경향이었다. 따라서 각 처리별 결과를 토대로 둥근산꼬리풀을 육묘시 162구 트레이에 원예상토를 충진한 후 셀 당 1립 파종하여, 55% 차광에서 재배하며, 추비는 Hyponex $1000mg{\cdot}L^{-1}$를 잎이 충분히 젖을 정도로 엽면시비하는 것이 가장 효과적일 것으로 생각된다.

• Clean Technology
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• v.17 no.2
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• pp.166-174
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• 2011

The xAl-yCe oxide catalysts with different mol ratios of Al/(Al+Ce) were prepared by a co-precipitation method and Pt supported on xAl-yCe oxide catalysts were synthesized by an incipient wetness impregnation method. The catalysts were characterized by X-ray Diffraction (XRD), $N_2$ sorption, and $H_2$/CO-temperature programmed reduction ($H_2$/CO-TPR) to correlate with catalytic activities in co oxidation. Among the catalysts studied here, Pt/1Al-9Ce oxide catalyst showed the highest activity in dry and wet reaction conditions and the catalytic activity showed a typical volcano-shape curve with respect to Al/(Al+Ce) mol ratio. When the presence of 5% water vapor in the feed, the temperature of $T_{50%}$ was shifted ca. $30^{\circ}C$ to lower temperature region than that in dry condition. From CO-TPR, the desorption peak of $CO_2$ on Pt/1Al-9Ce oxide catalyst showed the highest value and well correlated the catalytic performance. It indicates that the Pt/1Al-9Ce oxide catalyst has a large amount of active sites which can be adsorbed by co and easy to supplies the needed oxygen. In addition, the amount of pentacoordinated $Al^{3+}$ sites obtained through $^{27}Al$ NMR analysis is well correlated the catalytic performance.

• Journal of Dental Rehabilitation and Applied Science
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• v.34 no.3
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• pp.175-185
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• 2018

Purpose: The aim of this clinical study was to evaluate the efficacy and safety of a self - applied paint - on whitening gel combined with wrap to increase the effect of a whitening gel and minimize gingival irritation. Materials and Methods: Ninety adult volunteers were randomly treated to a control group and two experimental groups using whitening gel containing 2.8% and 3.0% hydrogen peroxide for 30 persons each. They had used the wrap and whitening gel on maxillary 4 anterior teeth for 30 minutes per day during 2 weeks. Whitening tooth color response was measured by VITA shade guide and ShadeEye $NCC^{(R)}$. And side effects were assessed from interview and intraoral examination. The efficacy and safety evaluations were statistically analyzed. Results: In the evaluation with VITA shade guide, there was significantly the whitening effect in experimental groups compared with the control group. In the evaluation with ShadeEye $NCC^{(R)}$, the 3.0% experimental group showed significantly the whitening effect compared to the control group and the 2.8% experimental group (P < 0.05). There were some complaints of minor side effects, but there did not find abnormal symptoms of the gingival stimulation in all groups. Conclusion: A self - applied paint - on whitening gel combined with wrap can be used as a useful self-whitening material because the whitening effect increases as the concentration of hydrogen peroxide from 2.8% to 3.0% and also no significant side effects are observed.

• Asian Journal of Turfgrass Science
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• v.20 no.1
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• pp.107-118
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• 2006

This study was carried out to introduce a couple of commercialized patented technologies in the area of turfgrass production. All sod production related patents in Korea during the period from Dec. 20, 1948 to Dec. 30, 2005 were reviewed. Details of two patents (patent No. 0434389 and 0478194) were included. The results are summarized as follows: 1. One of the domestic patents on sod production was the technique using natural and plastic films. Information on topsoil mixtures was also reviewed form foreign patents. 2. Patented multi-purpose sowing equipment can evenly mix soil, sand, fertilizer and other soil conditioners with seed, stolen and rhizome of turfgrass. 3. Patent on cool-season turfgrass sod production provide topsoil mixture combination and mixing ratio for sports field, landscape area and roof garden.

• Microbiology and Biotechnology Letters
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• v.32 no.4
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• pp.341-346
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• 2004

The quantification of the toxicological effects of the heavy metals such as Cu, Cd, Cr, Hg, and Zn on the growth of Escherichia coli was performed, and the variations of toxicwith exposure time were evaluated in adaptation procedure. The characteristics of growth inhibition on Escherichia coli by heavy metals were different with metal species, and critical concentration of each metal, which inhibited cell growth completely, were Cu of 3.5 mM, Zn of 2.5 mM, Cd of 1.5 mM, Cr of 1.2 mM, and Hg of 0.12 mM, respectively. The tolerance of E. coli against heavy metals, based on $EC_{50}$ values, increased in order of Cu > Zn > Cr > Cd > Hg. The slopes obtained from the relationship between ECso values and expose time corresponds to adaptability of test organisms to the toxicants. The adaptability of test organisms to the toxicants was much higher at higher slope values. Adaptability of E. coli on heavy metals increased in order to Zn > Cd > CU >> Cr> Hg.