• The tire
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• s.192
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• pp.52-52
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• 1997

• 레미콘
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• no.9 s.21
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• pp.13-23
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• 1989

• 레미콘
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• no.12 s.10
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• pp.38-44
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• 1986

• Cement
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• s.168
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• pp.69-74
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• 2005

서울시, 자연녹지에 레미콘공장 허용(2005.7.15)/ 매출 다각화 나섰다, 시멘트업계 건자재 증대, 신사업 진출(2005.7.20)/ "직원과 함께 땀흘린다" 라파즈 그룹 CEO 현장 경영(2005.7.25)/ 한일, "레미탈, 전국권 시멘트로 육성"(2005.7.27)/ 중국산 저질건자재 활개, 비규격 철근 · 시멘트, 국산으로 둔갑/ 중국, 상반기 시멘트 생산량 7.4% 증가(2005.8.2)/ 2010년 일본 건설투자, 51조엔(2005.8.16)/ 건교부, 건설폐기물 재활용 촉진(2005.8.25)/ 시멘트업계 '첨단경영 시대' 성신양회 · 한일 등 정보인프라 시스템 구축(2005.8.31)/ 8.31 부동산종합대책 발표(2005.8.31)/ 동양, 고온가스 재활용 일석이조(2005.9.1)/ 쌍용, 11월 워크아웃 졸업(2005.9.2)/ 일본, 시멘트 수요 호조세(2005.9.12)/ 골재 공급물량 넘친다(2005.9.19)/ 레미콘 공장은 '늘고', 수요는 '줄어'(2005.9.20)

• Applied Chemistry for Engineering
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• v.29 no.4
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• pp.399-404
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• 2018

This study compared the tackiness and adhesion of different tire tread compounds and rubber cements before and after vulcanization. The tackiness of natural rubber (NR) cement was the highest for all tread compounds before vulcanization, and the decrease in tackiness of NR cements over time was smaller than that of synthetic rubber cements. The tackiness before vulcanization was affected by the glass transition temperature of the rubber used in the cement and the decrease in tackiness over time of NR was smaller compared to that of using the synthetic rubber. The adhesion of NR-based cements after vulcanization was high for NR tread compounds but low for synthetic rubber tread compounds. On the contrary, the adhesion of emulsion (SBR) and solution SBR cements was high on all tread compounds which was shown to be higher when the rate of vulcanization of cement rubber was lower.

• Cement
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• s.37
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• pp.4-11
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• 1970

최근 급속히 팽창된 산업 구조와 이에 따른 업무량의 증가는 종래의 관리기술로서는 이를 성공적으로 처리할 수 없게 되었으며 아울러 인간의 미래조작능력의 증대와 기업구상력의 개발, 사회변동에 대비한 예측적인 계획의 수립 등 관리기능의 신장은 새로운 관리기법을 요구하게 되었으므로 PERT/CPM 수법이 신관리기법의 하나로 등장하게 되었다. PERT/CPM 이란 Program Evaluation Review and Technique, Critical Path Method 의 약자로서 우리말로는 계획수립 집행 및 평가로 번역되는데 이의 직역은 종속 및 총합 $\ulcorner$시스템$\lrcorner$ 과업의 동시진행 및 집중관리라 할 수 있는 것으로 시간과 비용을 절감하려는 기법인 것이다. 또한 PERT 기법은 복잡한 작업형태를 상호관련성있는 Network로 구성하고 제종속작업을 하나의 통일된 목표로 진행시키는 것을 의미한다. 이와 같은 PERT/CPM 기법은 제한된 자원의 효율적인 투자 및 관리와 불필요한 시간과 비용을 제거하여 준다. 현재 정부(경제기획원)는 PERT/CPM 제도를 도입하여 건설공사에 대한 예산관리제도를 설정중에 있으며 민간 및 정부투자기관으로서 현대건설주식회사와 한국전력주식회사와 이미 PERT/CPM 제도화방책을 연구기관에 위촉하여 제2단계적용을 시도하고 있는 것은 시대적 당위성에 따른 타당한 전망이라 하겠다. 거금 한국양회공업협회가 본제도의 도입 적용을 추진하기 위한 일련의 조사활동을 시작한 것은 시멘트 공업계의 새로운 경영관리체제를 모색하고 업계를 선도하는 중요한 전환점이 되리라 믿는다.

• Journal of the Korean Geographical Society
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• v.30 no.1
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• pp.16-34
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• 1995

This study aims to analyze the impact of cement industry on region change. For this study Maepo-Eub was selected as study area, where three cement factories are located. The data for analysis were obtained from interviews, questionaire surveys and the employee list of each cement factory. The analytic procedures for this study are as follows: 1) The change of regional employment was analyzed by development was industry in terms of the permanent address, education level, occupational status of the employee. 2) The degree of population growth are analyzed by developmental staae of the industry. Some conclusions from this study follows: 1) As these cement factories were built at Maepo in the 1960's, there were plenty of employment opportunities. Thus many technicians and workers flooded in Maepo-Eub. in the 1970's with the expansion of production facilities therewere much more immigrants to the industrial region, while there were outflow in the neighboring rural areas. In the 1980's the opportunity for the employment of cement factories have been decreased due to the introduction of the automation processes and larger, sized machines. Among the employee of three cement factories the native of Chungcheongbukdo (65%; in them Danyang 52%, Jecheon 32%) is dominant, the second is from Kangwon-do (13%), and the third is from Kyungsangbuk-do (11%) adjacent to Chungcheongbuk-do. It means that there are more employment opportunity in the near places of cement factories. 2) In the period of 1960's study area had experineed rapid social increase in population by the development of cement industry. That is, cement industries created new job opportunities and attracted large population concentration into this area. In the period of 1970's the population of the industrial region have increased continuously, while the population of neighboring rural areas have decreased. In the period of 1980's the population of Maepo decreased steadily because of decrease of labour forces through automation and commuting. Thus in the early stage of idustrial development large population concentrated in the neighboring villages of cement factories, and formed residential areas, commercial areas and service areas. As agricultural and was encroached, rural people left their regions to live in the more convenient suburbs. 3) People engaged in cement industry think that cement industry has a favorable influence on regional development, such as creating job opportunity, raising income level, developing business and service sector, and leading high economic growth. While farmers and some people think that cement industries as a pollution causing factories have a harmful influence on regional development, sucha as injuring the crops, causing environmental pollution, and being harmful to health. If pollution problems are solved, I think Maepo will play an important role as a regional center which can offer employment opportunity, business and service function to pheripheral rural areas, and raise a income level.

• Applied Chemistry for Engineering
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• v.20 no.5
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• pp.505-510
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• 2009

It is well known that the properties of concrete such as the compressive strength, water permeability, water tightness and durability are affected by micro-structure in hardened cement paste. Especially, for durability of concrete, watertightness of cementitious materials is the most critical property among various properties. Recently, many types of material such as organic and/or inorganic materials are used for watertightness of concrete. In this study, we examined the effect of fluorine-based emulsion on watertightness property. And we also discussed the change of microstructure and formation of hydrates in hardened cement paste by the addition of fluorine-based emulsion. Cement paste with fluorine-based emulsion showed improvement of watertightness by the surface activation of cement paste and by formation of $CaF_2$ fine crystals in cement pore structure.

• Applied Chemistry for Engineering
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• v.16 no.2
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• pp.180-186
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• 2005

This paper discusses the development of mixtures for silica fume as a stabilization/solidification agent and a binder for industrial wastewater residue containing organic and heavy metal contaminants. The UCS (unconfined compressive strength) gradually increased to 66.7% as the silica fume content increased to 15%. The leaching of TOC (total organic carbon) and chromium decreased as more OPC (Ordinary Portland Cement) was substituted with the silica fume. When a mixture had 5% silica fume, it retained about 85% TOC, and chromium leached out 0.76 mg-Cr/g-Cr in acidic solution. Also, microstructural studies of the solidified analysis showed that the silica fume caused an inhibition to the ettringite formation which did not contrilbute to setting but coated the cement particles and retarded the setting reactions. The results indicated that the incorporation of silica fume into the cement matrix minimized the detrimental effects of organic materials on the cement hydration reaction and the contaminant leachability.

• Cement
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• s.71
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• pp.44-50
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• 1978

오늘날 grate식 냉각기는 일산능력 7,000둔급의 공장에서 가동중에 있는 일산능력 10,000둔급 공장의 것이 설계단계에 있다. Planetary식 냉각기의 현재 최대능력은 일산능력 약 50,000둔급이지만 서서히 대형화하는 경향에 있다. Rotary식 냉각기는 일산능력 약 2,000둔급의 것이 가동중이다. 현재의 크링카 냉각기는 일장일단이 있으며 모든 크링카 소성장치에 공통으로 최적한 냉각기는 아니다. 시멘트 제조업자는 키른에 적합하게 특별히 제작된 최적의 방법을 선택하기 위해서 끊임없는 노력을 계속해야만 할것이다. 한편 냉각기 제조업자들은 오늘날 시장에 있는 모든 냉각기가 개선의 방향으로 끊임없는 노력을 해야만 할 것이다.