• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.208-211
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• 2004

In order to obtain improved concrete mix proportion on nuclear power plant structures, the properties of normal concrete is compared with self-compacting concrete. In addition, various mixes of self-compacting concrete utilizing melaminic acid based admixture is mutually compared and estimated. Because existing normal concrete mixes might occur high temperature in concrete structure, A new multi-component concrete, which declines hydration heat, is demanded. Therefore, in this study, the possibility of manufacturing self-compacting concrete is verified and what influences melaminic acid and various powders have on the properties of self-compacting concrete are investigated.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.415-418
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• 2005

Nowadays the three major commercially available of organic chemical admixtures are modified lignosulfonates(LS), sulfonated naphthalene-formaldehyde resins (SNF) and sulfonated melamine-formaldehye (SMF). In this study, various sulfonated melamine-formaldehyde (SMF) superplasticizers were synthesized via four synthetic steps. Hydroxymethylation (Step 1), Sulfonation (Step 2), Polymerization (Step 3) and Neutralization and Stabilization (Step 4). In this synthesis of SMF, reaction conditions such as the mole ratio of melamine to formaldehyde and the amount of acid catalyst were changed. After application of SMF superplasticizer to cement paste and mortar, the physical properties including workability, slump loss, compressive strength were compared.

• 월간산업보건
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• s.249
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• pp.37-45
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• 2009

최근 들어 광우병 소고기, 멜라민분유, 식품첨가물 등과 관련한 여러 사건들이 발생하여 대중들에게 식품선택에 있어서 공포와 혼란을 가져왔다. 대기, 수질, 토양, 주거, 식품 등의 환경 영역은 21세기를 살고 있는 우리들에게는 과거 어느 때보다도 더욱 큰 관심을 유발할 뿐만 아니라 실제 인류의 생존에도 중요한 문제가 되고 있다. 올 한해 발생한 여러 환경문제 중 식품환경만큼 대중들의 관심을 촉발한 때는 없었을 정도로 많은 사건들의 연속이었다. 예를 들면, 위의 식품관련 사건 외에도 태안반도의 허베이스피릿호 기름유출사건, 지하철 역사 내의 석면문제, 포장용기 등에서 방출되는 환경호르몬, 휴대폰의 전자파 문제 등과 같은 문제들은 이 땅에 살고 있는 어느 누구도 자유로울 수가 없다. 그러나 사건이 발생할 때마다 정부당국, 기업, 시민단체, 학자 등의 이해당사자들의 의견은 다양한 정보를 넘어 상반되는 입장으로 대중들을 더욱 혼란케 하였다. 본 기고에서는 환경문제를 중심으로 하여 대중들에게 혼란을 유발하는 여러 위해(risk)를 접하면서 대중과 소통하기 위한 원칙들을 제시하고자 한다.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.7 no.2
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• pp.100-107
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• 1998

Diamond wheels with fine grains and multi-porous structures are newely trial developed for smoothing and mirror finishing materials. Grinding wheel must have performed both to remove tool marks efficienitly and to contact elastically with curved surfaces, that are employed for ultra precision and high performance grinding of difficult-to materials such as tungsten carbide alloy using tool and die materials, Diamond grains are bonded by a melamine resin to prevent the decrease of machining efficiency due to grain sinking within the bond materials. Also, highly foamed structures are developed to increase the flexibility of the grinding wheel, and to induce self-sharpening by increasing contact pressure between the grinding wheel and workpiece surfaces. In this paper, melamine-bonded diamond wheels try to manufacture, then the forming method of grinding wheel are suggested, and the grinding characteristics of melamine-bonded diamond grinding wheel are also illustrated.

• Fashion & Textile Research Journal
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• v.7 no.1
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• pp.81-84
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• 2005

Skin patch test and antibacterial properties of the reaction products between poly(hexamethyl biguanide) hydrochloride and trimethylol melamine on textile fabrics were examined. Antibacterial activities of anti-microbial agent treated samples are very good. The reduction ratios against four kinds of colonies are 99.9 % after repeated laundering ten times. Skin patch test results for anti-microbial agent treated samples are almost-negative by Hi-scope judgement and macroscopical judgement.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.5
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• pp.578-584
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• 2011

In mechanical cutting process, burr was generated at workpiece by cutting tool generally. It is working disturbance during manufacturing process. Besides burr was taken shape relatively large size more micro scale machining than macro scale machining. Many researches have been studied to remove micro burr(de-burring), because it was negative effect for accuracy of machining shape. However, micro de-burring was constrained by burr height, micro feature and so on. In this paper, experimental research was carried out to compare de-burring characteristics of $Al_2O_3$ abrasive and polymer.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.11a
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• pp.316-317
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• 2015

무전해 도금은 금속이온을 수용액 상태에서 석출시키는 방법으로서 전기를 사용하지 않고 환원제의 자기촉매 방법에 의해 금속을 도금하는 방법이다. 두께를 확보하기 위한 화학적 무전해 도금에서는 환원제를 사용하지만 선택적 도금에서는 환원제를 사용하지 않는 치환도금법이 주로 사용되고 있다. 최근 전자파 차폐, 포장기술의 응용이 확대되면서 정보 통신 스마트폰, 전자기술과 자동차 산업에 많은 고분자 복합도금이 널리 확대되고 있다. 최근 해외에서도 고분자와 비금속재료의 복합도금 기술이 관심을 끌고 있다. 2013년 중국의 J. B. Fei 등은 Ag나노체인 합성물에 필요한 비대칭형의 공유결합으로써 나선형의 자기배열 $AgNO_3$와 멜라민 특성을 보고하였다. 무전해 니켈 복합도금은 내마모성, 내식성과 비금속재료의 선택적인 첨가로 다양한 고분자 첨가물을 적용할 수 있다. 유전상수가 낮고 열적 안정성이 우수하여 노트북 컴퓨터나 스마트폰 표면에 니켈-폴리이미드 복합도금도 개발되고 있다.

• Journal of the Korean Wood Science and Technology
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• v.12 no.1
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• pp.38-43
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• 1984

Water soluble urea-melamine-phenol copolymer adhesive manufactured with 80 percent of urea resin contents was manufactured by different molar ratio for a high temperature curing type, and their properties and strengthes were examined through manufactures of plywood with Kapur (Dryobalanops spp.) veneers. The results are summarized as follows: 1. Specific gravities of air dried plywood manufactured from each adhesive ranged from 0.78 to 0.84 and their moisture contents met the KS requirement. 2. In dry and wet shear strength, $U_{80}M_{10}P_{10}$ copolymer resin showed the highest value and urea resin was the lowest, indicating that melamine and phenol were effective for increasing glue shear strength of urea resin. 3. In case of glue shear strength after boiling test, phenolic resin was the nest and melamine was not so effective as phenol on reinforcement of boiling water resistance of urea resin.

• Proceedings of the KSRS Conference
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• 2009.03a
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• pp.323-326
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• 2009

최근 국내외적으로 고소득 및 친환경농산물 시장이 농업인과 소비자들의 관심이 커지면서 지속적으로 성장하고 있다. 특히 최근 '미국산 소고기' '멜라민' '식품첨가물' 등의 파동을 계기로 안전한 먹을거리에 대한 소비자들의 욕구가 그 어느 때보다 높아진 상황이다. 이러한 현실에서 보다 체계적이고 과학적인 농업행정관리와 우수작물을 대량생산하기 위해서는 농업기반 정보와 기법에 대한 기술개발이 수행되어야 한다. 본 연구는 고소득 작물 및 안전한 농산물 생산과 관리를 위한 의사결정자료 제공을 목적으로 하며, 그 기반으로 고해상 위성영상 및 세부정밀토양도와 농작물 생산정보를 GIS로 데이터베이스화 및 Web기반 농업정보 통합관리 시스템을 구축하고자 한다.

• Journal of the Korea Furniture Society
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• v.17 no.1
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• pp.83-89
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• 2006

Because the surface of pine wood is very soft, there have been many attempts, like as surface coating, resin impregnation, and densificationt, to harden the surface of wood for its interior use. This study was carried out for surface hardening of pine wood by laminating of melamine resin sheet. The effect of laminating method on the characteristics of melamine resin sheet-laminated wood(MLW) was investigated. Flat-sawn softwoods were suitable for MLW making. And the pre-drying of wood at $105^{\circ}C$ for 30min, before laminating, was effective for preparing of defect-free MLW. The abrasion resistance of pine wood was greatly improved by laminating of melamine resin sheet on its surface. Consequently, the laminating of melamine resin sheet was proved to be a favorable method for improvement of surface abrasiveness of pine wood.