• 자원리싸이클링
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• 제28권3호
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• pp.21-25
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• 2019

The utilization of incineration ash from municipal waste must be promoted to solve the social problem on the shortage of final disposal site. In this research, metals should be recovered to avoid the damage of the crushing machine during the utilization of incineration ash in cement industry. In fact, incineration bottom ash from municipal waste contains iron in 3-5%. Nonferrous metal and stainless steel in 1% is also included. The research and development on the physical recovery process was performed not only to remove the metals but also to recover high grade products. Metals were separated from incineration ash in Maruya Co. Ltd.. In fact, iron scrap recovered by magnetic separation can be selled. After that, mixed metal was separated from incineration ash using screen. In this research, mixed metal tried to divided copper, aluminum, brass and stainless steel using drum type magnetic separation, eddy current separation and high magnetic separation. As a result, recovered iron had an 80% for the grade. Aluminum was recovered by eddy current separation without copper and brass.

• Corrosion Science and Technology
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• 제10권5호
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• pp.175-179
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• 2011

The transportation and deposition of iron corrosion products are important elements that affect both the steam generator (SG) integrity and secondary system in pressurized water reactor (PWR) nuclear power plants. Most of iron corrosion products are generated on carbon steel materials due to flow accelerated corrosion (FAC). The several parameters like water chemistry, temperature, hydrodynamic, and steel composition affect FAC. It is well established that the at-temperature pH of the deaerated water system has a first order effect on the FAC rate of carbon steels through nuclear industry researches. In order to reduce transportation and deposition of iron corrosion products, increasing pH(t) tests were applied on secondary system of A, B units. Increasing pH(t) successfully reduced flow accelerated corrosion. The effect of increasing pH(t) to inhibit FAC was identified through the experiment and pH(t) evaluation in this paper.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2002년도 춘계공동학술대회
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• pp.109-113
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• 2002

Steel industry is the most capital intensive and the largest energy consuming industry, which operate huge and complex facilities to supply various steel products as the primary materials to almost every manufacturing industry Major steel products are hot-rolled and cold-rolled coils, plates, and wires that are produced through molten iron making, molten steel making, casting, and rolling. Each process runs in batch between setups and the specifications or bach are different with each other High energy consuming and heavy material handling require careful synchronization or processes, as well. Considering the synchronization or processes, the lot planning and scheduling problem in the integrated steelmaking process rovers the roll grouping with given casts. the sequencing or rolls over time, and the machine assignment and time scheduling or charges and casts. The problem is investigated by dividing it into two cases whether single or parallel machines at the molten steel making and the continuous casting processes. Problem descriptions and solution approaches or each instance are introduced. To test their performance and conformity, implementation or the algorithms and numerical experiments are carried out with real world and constructed data sets.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2003년도 추계학술대회
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• pp.151-160
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• 2003

The company was focusing on production which was partial mission rather than acquiring the information of customer in intensive process industry. The company accepted loss which is from over-production, losing of opportunity. After changing to Web environment, supply chain is more complicated and need of customer is more various. As a result the company hard works on controlling production rates, production quantities in production area and gathering exact information which is about available resource and available quantities. Cooperated demand planning have to get decreasing of inventory, improving of customer service in supply chain management. Specially demand planning that considers allocation of capacity is executed in Iron-Industry. Demand planning must be classified by customer, region and supply position level.

• STI Policy Review
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• 제2권3호
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• pp.1-12
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• 2011

North Korea is now under the pressure of international sanctions due to its nuclear tests, firing of long-range ballistic missiles, the sinking of the ROK naval frigate the Cheonan, and the artillery attack on Yeonpyeong Island that killed four people. To overcome the burden of sanctions North Korea has exerted various efforts to reconstruct its industries. However, it is very unlikely that these reconstruction efforts would produce significant results due to the structural problems of the antiquated infrastructure of North Korean industries. In the future, it is expected that South Korea will have to cooperate with North Korea for the reconstruction of the North Korean economy after the North Korean nuclear issue will be peacefully resolved. South Korean government has to prepare for the reconstruction with careful planning based on analysis of North Korean industries. But, the number of previous studies that have analyzed the technological level of North Korean industries are quite limited. In preparation for the future inter-Korean industrial cooperation, this study tries to analyze the technological level of North Korean industries. The steel industry has been selected as the focus for the main analysis of this study due to the importance of the steel industry as one of key infrastructure industries. Additionally, this study tests the sustainability of the North Korean steel industry by looking into the possibility of whether the North Korean steel industry can sustain or grow while maintaining global competitiveness in the future when the market opens to the world. Such analysis is expected to contribute to the joint prosperity of two Koreas in the short term and the reduction of unification costs in long term.

• 한국산학기술학회논문지
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• 제13권11호
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• pp.5601-5609
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• 2012

본 논문은 포항철강공단 및 주변지역의 보건 및 환경영향 인자를 확인하기 위하여 미세먼지($PM_{10}$) 농도와 성분을 측정 및 분석하였다. 또한 지역대기자동측정망 자료를 이용하여 연별, 계절별 $PM_{10}$ 농도분포를 조사하였다. 공단지역 내 $PM_{10}$을 측정한 결과, 동일산업에서 측정된 $PM_{10}$ 평균농도는 $61.3{\pm}12.1{\mu}g/m^3$, 철강공단관리사무소에서 측정된 $PM_{10}$ 평균농도는 $44.3{\pm}8.1{\mu}g/m^3$으로 나타나 대기환경기준을 만족하였다. 공단지역 동일산업과 철강공단관리사무소에서 측정된 $PM_{10}$ 중 이차생성 이온인 ${SO_4}^{2-}$, $NO_3{^-}$, $NH_4{^+}$의 분율을 확인한 결과, ${SO_4}^{2-}$의 분율이 높게 나타났고, 황산염과 관련된 오염원이 철강공단지역에 존재하는 것으로 판단된다. 전체적으로 동일산업 지점에서는 ${SO_4}^{2-}$ > $Cl^-$ > $NO_3{^-}$ > $F^-$ > $NH_4{^+}$ 순으로 나타났고, 철강공단관리사무소 지점에서는 ${SO_4}^{2-}$ > $Cl^-$ > $NO_3{^-}$ > $NH_4{^+}$ > $F^-$ 순으로 나타났다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.432-436
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• 2001

In this study, calcium sulfate(gypsum) powder was obtained using waste sulfuric acid and stainless refinery sludge by- produced from chemical reagent and the iron industry, by the neutralization of waste sulfuric acid. As variables for the experiment the mole ratio of the H$_2$SO$_4$ : Ca(OH)$_2$, the pH, the reaction temperature and time, the amount of catalyst were used. The crystal shape and microstructure of obtained powder were observed by XRD and SEM, and the thermal property was investigated by DTA. As the NaCl is added 0~20wt% as a catalyst to the H$_2$SO$_4$ : Ca(OH)$_2$, system it can be found that the crystal shape goes through the processes as follows : gypsum dihydratlongrightarrowgypsum hemihydrate＋gypsum dihydratelongrightarrowgypsum hemihydrate. And gypsum hemihydrate is $\beta$-type as the result of DTA. As waste sulfuric acid and stainless refinery sludge were used, the pH of reacted solution (which was 0.8) was rapidly raised up to 8~9 by the addition of stainless sludge and gypsum dihydrate was produced as a by-product. Therefore, it was found that stainless refinery sludge is sufficiently applicable for the neutralization of waste sulfuric acid.

• 한국물환경학회지
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• 제20권2호
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• pp.104-109
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• 2004

Removal of nutrients from domestic sewage or industrial wastewater is needed to protect surface waters from eutrophication. This research was carried out to remove the nitrogen (N) and phosphorus (P) from the wastewater using the iron oxide obtained from the steel industry and the natural zeolite, respectively. This research was conducted in both batch and continuous systems. The removal efficiency of the nutrients was evaluated in the batch system using the varying concentrations of zeolite and iron oxide added. The removal efficiency of N was 60% at the 8g of zeolite added. In the same condition, the removal efficiencies of N were 76% and 82% at 12g and 16g of zeolite added, respectively. Removal efficiency of P was 80% as 8g of iron oxide was added. The removal efficiency of P was correspondingly increased as the concentration of iron oxide was increased. Continuous column system was also used to evaluate the removal efficiency of N and P by the addition of zeolite and ferric oxide, respectively. Removal efficiencies of N were compared in the mixed packing, two stage, and four stage columns, respectively. The removal efficiencies (80%) of N in the separate packed columns (two and four stages) were higher than the mixed packing column (400%) after 90 hr. Whereas, the removal efficiencies of P were similar to each other in the three columns.

• 한국산업융합학회 논문집
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• 제7권3호
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• pp.259-263
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• 2004

In the manufacture progress of LCD or semiconductor, there are used many kinds of gas like erosion gas, dilution gas, toxic gas as a progress which used these gas there are required high puritize to increase accumulation rate of semiconductor or LCD materials work progress of semiconductor or LCD it demand many things like the material which could minimize metallic dust that could be occured by reaction between gas and transfer pipe laying material, illumination of the surface, emition of the gas, metal liquation, welding etc also demand quality geting stricted. Material-Low-sulfur-contend (0.007-0010), vacuum-arc-remelt(VAR), seamless, high-purity tubing material is recommend for enhance welding lower surface defect density All wetted stainless steel surface must be 316LSS elecrto polishinged with ${\leq}0.254{\mu}m$($10.0{\mu}in$) Ra average surface finish, $Cr/Fe{\geq}1.1$ and $Cr_2O_3$ thickness ${\geq}25{\AA}$ From the AES analytical the oxide layer thickness (23.5~36 angstroms silicon dioxide equivalent) and chromum to iron ratios is similar to those generally found on electropolished stainless steel., molybdenum and silicon contaminants ; elements characteristic of stainless steel (iron, nickel and chromium); and oxygen were found on the surface Phosphorus and nitrogen are common contaminants from the electropolish and passivation steps.

• 헤리티지:역사와 과학
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• 제52권3호
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• pp.240-251
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• 2019

울산 하대고분에서 출토된 판상철부의 미세조직을 금속학적 방법으로 분석하여 제작기술을 살펴보았다. 또한 기존의 판상철부 연구자료와 비교 및 검토하여 판상철부에 적용된 다양한 제작기술을 파악하였다. 울산 하대고분 44호 목곽묘에서 나란히 배열된 상태로 출토된 판상철부 10점을 과학적으로 분석한 결과, 판상철부의 제작기술 체계를 '(1) 순철-형태 가공, (2) 순철-형태 가공-침탄, (3) 순철-형태 가공-침탄-탈탄' 세 가지 유형으로 분류할 수 있었다. 판상철부는 모두 단조에 의해 제작되었고, 순철을 소재로 두드려 형태를 만들었다. 특히 다수의 판상철부는 형태 가공 후 침탄 처리를 통해 재질을 강화시켰는데, 이는 중간 소재 또는 화폐로 통용됨으로써 당시 제철산업의 근간을 이루었던 철강 제품인 것으로 보인다. 한편 형태 가공이나 침탄 이후에는 담금질이 실시되지 않았다는 공통점을 가진다. 순철을 소재로 제작한 판상철부의 미세조직에는 불순 개재물이 다량 포함되어 있고, 비금속 개재물을 성분 분석한 결과, 유리상과 뷔스타이트가 함께 혼재한 철재(鐵滓)의 특징을 보여주므로 제련 공정에서 저온환원법이 적용되었을 가능성이 크다.