• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.127.1-127.1
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• 2010

고체산화물연료전지는 고효율 및 무공해의 전기화학 에너지 변환장치로서, 최근 국내외에서 활발한 연구개발이 수행되고 있다. 특히, 고체산화물 연료전지 시스템의 조기 상용화를 위해 시스템의 작동온도를 약 $800^{\circ}C$ 이하로 낮추고 저가로 생산 할 수 있는 제조공정 개발에 대한 연구를 적극적으로 수행하고 있다. 본 연구에서는 고체산화물연료전지의 단위셀를 구성하는 연료극지지체 및 박막 전해질에 대해서 저가 양산의 테이프케스팅법 및 동시소성 공정, 그리고 연료극 지지체 전해질(anode-supported electrolyte)에 대한 공기극 페이스트 프린팅 제조공정에 대해 소개한다. 또한 고체산 화물연료전지의 제조공정 및 시간을 단축하기 위해 방전플라즈마 소결공법(SPS)에 의한 연료극 지지체 제조 공정, 단위셀의 성능 최적화를 위한 나노 스케일의 고성능 전해질 소재 분말합성 공정(crystallite size: 5~10nm, surface area : $100m^2/g$ 이상) 그리고 테이프케스팅에 의한 박막 전해질 제조 공정(thin film : $10{\mu}m$ 이하) 등 주요 단위셀 소재 및 부품의 제조공정 특성 그리고 단위셀의 전기화학적 특성(max. power density : 1.0 W/$cm^2$)에 대해 소개하며, 최종적으로 평판형 대면적 고체산화물연료전지(max. $20cm{\times}15cm$)의 단위셀 상용화 제조 기술 및 성능평가 기술에 대해서도 소개 할 예정이다.

• Journal of Wetlands Research
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• v.7 no.3
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• pp.33-39
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• 2005

Constructed wetlands are considered as an important tool for wastewater treatment, wastewater management and flooding control. In addition, one of the most promising technologies for application in many countries seems to be constructed wetlands due to their properties such as utilization of natural processes, simple construction, operation and maintenance, process stability, cost effectiveness, etc. This research is performed to find the possibility for treating livestock wastewater using a constructed wetland. The removal efficiencies of CODcr, TN, TP, SS, and color were 97.9%, 97.8%, 97.2%, 99.1%, and 84.9%, respectively. In particular, SS was completely removed. In conclusion, constructed wetlands could be applied to livestock wastewater treatment. Further, it needs time for stabilization to reduce the pollutants accumulated in soil.

• Journal of the Korean GEO-environmental Society
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• v.3 no.4
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• pp.67-79
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• 2002

The purpose of this study is to present criteria of selection of optimum grout materials through analyzing the limitation of permeability of each materials(MSG-N, OPC), in various ground conditions by comparing presentation of strength and permeability of MSG method and LW method(or SGR method). To do that, physical and chemical characteristics of grout materials were analyzed and compressive tests of homogel, mixed coagulation materials and hardening materials in certain mixing ratio, and of milk paste. In addition, permeability tests for each ground soil, each injection pressure, and each materials in combined stratum were performed with massive chamber. The results of tests showed that ultra fine grout materials like grout of MSG is necessary to construct effective grouting in sand and silty sand ground. Also, it is expected to become chemical grouting guide data to layout construction engineers because presented proper injection pressure by kind of object ground in case using ultra-fine grout material.

• Korean Chemical Engineering Research
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• v.51 no.6
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• pp.745-754
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• 2013

This study evaluated the optimal soil washing conditions for toxic metals considering the removal efficiency of toxic metals from contaminated soils as well as from soil washing effluents. In the contaminated soils, As was the major contaminant and extracted by sodium hydroxide solution better than by sulfuric acid. However, in the case of the treatment of soil washing effluents, sodium hydroxide was less effective extractant because soil organic matter extracted by sodium hydroxide prevented the solid-liquid phase separation and toxic metal removal. In the treatment of soil washing effluents with sulfuric acid, toxic metals in the effluents were mostly precipitated at the pH above 6.5. In addition, granular ferric oxide (GFO) as an adsorbent enhanced the removal of As and Pb indicating that toxic metals in the washing effluents can be removed almost completely by the use of combined adsorption-neutralization process. This study suggests that soil washing techniques for toxic metals should be optimized based on the physical and chemical properties of the contaminated soils, the nature of chemical extractant, and the removal efficiency and effectiveness of toxic metals from the soils as well as soil washing effluents.

• Magazine of the Korea Concrete Institute
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• v.18 no.5 s.94
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• pp.16-22
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• 2006

• Journal of Wetlands Research
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• v.25 no.2
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• pp.91-98
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• 2023

Some concrete wastewater generated during construction is in the form of non-point pollution sources that workers, managers, and users are unaware of, and it is not easy to manage as it flows through sewage pipes. Due to these characteristics, construction sludge is inflow into rivers and sewage pipes in the form of non-point pollution sources in an unmanaged state. This study applied the D.W.S method to the concrete retaining wall removal method installed on the road, and the resulting concrete wastewater was physically and chemically treated through a mobile sewage treatment facility, and it was examined whether it met the removal efficiency and wastewater discharge acceptance standards. Accordingly, it is intended to meet the standards for effluent concentration of wastewater during construction by removing 73.5% of BOD and 89.1% of SS through physical and chemical treatment through portable sewage treatment facilities during construction. In addition, we would like to review the adequacy and economic analysis of calculating environmental conservation costs for physicochemical treatment through portable sewage treatment facilities and sewage treatment generated during construction.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.5A
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• pp.519-529
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• 2009

Fiber reinforced composite materials have various advantages in mechanical and chemical aspects. Not only high fatigue and chemical resistance, but also high specific strength and stiffness are attained, and therefore, damping characteristics are beneficial to marine piles. Since piles used for marine structures are subjected to compression and bending as well, detailed research is necessary. Current study examine the mechanical behavior under flexural and/or compressive loads using concrete filled fiber reinforced plastic composite piles, which include large size diameter. 25 pile specimens which have various size of diameters and lengths were fabricated using hand lay-up or filament winding method to see the effect of fabrication method. The inner diameters of test specimens ranged from 165 mm to 600 mm, and the lengths of test specimens ranged from 1,350 mm to 8,000 mm. The strengths of the fill-in concrete were 27 and 40 MPa. Fiber volumes used in circumferential and axial directions are varied in order to see the difference. For some tubes, spiral inner grooves were fabricated to reduce shear deformation between concrete and tube. It was observed that the piles made using filament winding method showed higher flexural stiffness than those made using hand lay-up. The flexural stiffness of piles decreases from the early loading stage, and this phenomenon does not disappear even when the inner spiral grooves were introduced. It means that the relative shear deformation between the concrete and tube wasn't able to be removed.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.7
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• pp.387-394
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• 2016

Commercial 28 algae removal technologies that have been applied in domestic rivers and lakes with green tide were investigated, analyzed and classified. The classification of algae removal technologies was based on the three criteria (i.e., principle, flow rate of water body, and application period). Also, algae removal technologies were evaluated in terms of cost effectiveness, field applicability, effect durability, and eco friendliness. From the analysis results, technologies using physical, chemical, biological, and convergent controls were 32.2%, 25%, 21.4%, and 21.4%, respectively. The 75% of technologies have been applied to stagnant water body (${\leq}0.2m/s$). Also, algae harvesting ship with dissolved air flotation, conveyor belt and filtration processes and natural floating coagulant were found to have better field applicability, compared to other technologies. However, proper algae removal technology in specific rivers and lakes should be chosen after the evaluation of long-term pilot scale field test. Also, development of energy and resource recovery technologies from algae biomass is warranted.

• Product Safety
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• s.249
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• pp.44-47
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• 2014

두리화학(주)는 1974년 모체 공장인 대성화학을 창립한 이래 플라스틱 배관자재 생산 전문업체로 성장 발전해 왔다. 그동안 고객의 욕구를 충족시키고 고객 감동경영을 실현하기 위해 부단히 노력해온 두리화학(주)는, 최근 공동주택 배관 시스템의 최대 결점인 배수 소음 및 결로를 별도의 방음 및 보온 작업을 하지 않고도 배수소음 및 결로를 획기적으로 줄일 수 있는 공법을 개발하여, 국내 유수의 건설 업체에 납품하여 뛰어난 성능을 인정받게 되었다. 동종업계에서 국내 최대의 생산 설비와자동화 제조 공정을 갖추고 최고의 품질관리 시스템을 가동하여, 부적합품 발생 방지에 주력하고 있으며 사후 관리에도 만전을 기하고 있다. 또한 두리화학(주)는 기업의 최대 목적인 이윤을 추구함에 있어 사회적 책임을 다하고, "고객감동경영"의 경영철학을 바탕으로 무한경쟁시대의 21세기를 맞아, 항상 고객과 함께 연구하고 발전하는 기업으로 거듭날 것을 고객 앞에 다짐한다.

• Product Safety
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• s.246
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• pp.40-43
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• 2014

두리화학(주)는 1974년 모체 공장인 대성화학을 창립한 이래 플라스틱 배관자재 생산 전문업체로 성장 발전해 왔다. 그동안 고객의 욕구를 충족시키고 고객 감동경영을 실현하기 위해 부단히 노력해 온 두리화학(주)는, 최근 공동주택 배관시스템의 최대 결점인 배수 소음 및 결로를 별도의 방음 및 보온 작업을 하지 않고도 배수 소음 및 결로를 획기적으로 줄일 수 있는 공법을 개발하여, 국내 유수의 건설 업체에 납품하여 뛰어난 성능을 인정받게 되었다. 동종업계에서 국내 최대의 생산 설비와 자동화 제조 공정을 갖추고 최고의 품질관리 시스템을 가동하여, 부적합품 발생방지에 주력하고 있으며 사후 관리에도 만전을 기하고 있다. 또한 두리화학(주)는 기업의 최대 목적인 이윤을 추구함에 있어 사회적 책임을 다하고 "고객감동경영"의 경영철학을 바탕으로 무한 경쟁시대의 21세기를 맞아, 항상 고객과 함께 연구하고 발전하는 기업으로 거듭날 것을 다짐했다.