• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.797-800
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• 2008

To decrease the usage of cement, the pozzolan reaction materials are used as a mineral admixture. Hwang Toh which is broadly deposited in Korea is well known as a environment friendly material and the activated Hwang Toh which has the property of pozzolan reaction is practically used as a mineral admixture of concrete. PET fiber which is made by recycled PET bottle controls micro crack in concrete. But the study about concrete mixed with reinforcing fiber is not enough and the property of Hwang Toh concrete mixed with PET fiber is more complicated case. So this study performed drying shrinkage experiment to analyse mechanical property of Hwang Toh concrete mixed with PET fiber.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.1
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• pp.139-143
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• 2008

Recently, detections of huge amount of wastes in the unsanitary landfills at a residential development sites were reported. Because the sites were the residential development sites, all landfilled wastes should be removed for the constructions. Therefore the way that the unsanitary landfills were excavated and then the wastes were sorted into three categories such as soils, noncombustibles, and combustibles was selected as the best method. Soils and noncombustibles could be recycled in the sites and combustibles could be compacted and be relandfilled in a smaller area.

• Journal of the Korean Geosynthetics Society
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• v.10 no.2
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• pp.73-79
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• 2011

Based on the results of Part 1 of our two-parts paper, the possibility on field applicability of CMDS(Coal Mine Drainage Sludge) mixed with bentonite and cement as a liner in landfill sites was investigated. The optimum moisture content that met the landfill liner condition was obtained when the ratio of CMDS: bentonite: cement was 1: 0.5: 0.3 in a lab-scale. The relative compaction was measured in 90.1%, which results for construction field have been generally acceptable. In this study, a large-scale Lysimeter($1.0m{\times}1.5m{\times}2.0m$) was used to simulate the effects of the layer on the freeze/thaw by -20 average temperature. The mixture after freezing/thawing showed compressive strength more than $5kg/cm^2$, which was satisfied with EPA standards. Initial permeability of CMDS was $7.10{\times}10^{-7}cm/s$ and permeability its mixture after freezing/thawing was increased to $9.80{\times}10^{-7}cm/s$. The change of temperature in the layers rises and falls with linear and temperature gradient keep maintain the present state. Moisture contents in the layers have not been radically changed. Through the leaching test determined by KSLT method, it was found that heavy metals excluding Zn and Ni were not leached out or leached out less than the standards during 7 cycles of freezing/thawing process. Since it shows the increased permeability about 1.5 times and slight change in moisture content, but it was satisfied with EPA standar through 7 cycles of freezing/thawing process, this mixture can be applied as a liner in landfill final cover system.

• Clean Technology
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• v.10 no.2
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• pp.73-87
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• 2004

In most of industrial fields, cleaning is employed for removing soils on their products or parts. Halogenated cleaning agents such as CFC-113, 1,1,1-TCE(1,1,1-trichloroethane), MC(methylene chloride) and TCE (trichloroethylene) have been used as cleaning ones in most of companies in the world since their excellent performance of cleaning ability and good material compatibility. However, CFC-113 and 1,1,1-TCE which are ozone destruction substances are not used any more in the advanced countries because of the which are ozone destruction substances are not used any more in the advanced countries because of the Montreal protocol. MC and TCE are now used restrictively at small part of industrial fields in most of countries since they are known to be hazardous or carcinogenic materials. Thus, it is indispensible that the alternative cleaning agents which are environmental-friendly and safe, and show good cleaning ability should be developed or utilized for replacement of the halogenated cleaning agents. Aqueous/semi-aqueous cleaning agents are evaluated to be promising alternative ones among various alternatives in environmental and economical view point. In this study, commercially available 12 aqueous and 6 semi-aqueous cleaning agents were selected and their physical properties, cleaning abilities, rinsing abilities and recycling of contaminated rinse water were measured and analyzed. Aqueous cleaning agents with higher wetting index showed better cleaning ability compared with those with lower wetting index. However wetting index did not have any correlation with cleaning ability in semi-aqueous cleaning agents. It was observed that soil concentration in aqueous and semi-aqueous cleaning agents should be maintained below the certain concentrations which depend on types of clearing agents. More than 70% soils in contaminated rinse water by some of aqueous and semi-aqueous clearing agents could be separated by simple settling method. This means that some cleaning agents with high oil-water separation efficiency will be effiective for recycling oil-contaminated rinse water. It was found that contaminated rinse water with aqueous agents was purified easiy by ultrafiltration method with PAN membrane of 30 kDa.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.617-620
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• 2008

지열에너지는 지구 내부의 깊은 곳에서부터 발생하는 열과 상부 지각에서 방사성 동위원소의 붕괴에 의한 열에 의해 발생한다. 지열에너지는 다른 신재생에너지(수력, 풍력, 태양력, 조력, 바이오 매스등)에 비하여 가동효율이 높고, 지속가능한 재활용 자원으로 경제적 효율성이 높아 전 세계적으로 활용도와 잠재성이 높은 신재생에너지의 하나로 각광 받고 있다. 따라서, 지열에너지의 사용은 화석 연료 사용의 상당부분을 대체할 수 있고, 온실가스의 배출도 줄일 수 있다. 현재 우리나라의 지열에너지 이용은 저온성 지열에너지를 이용한 냉난방에 국한되어 있지만, 앞으로의 지열에너지 이용은 Enhanced Geothermal System(EGS) 을 이용한 지열에너지 개발에 초점이 맞추어질 것이다. 현재의 지열에너지 개발을 용이하게 하고, 또한 미래의 지열에너지 개발에 대비하여 우리나라의 이용가능한 지열에너지 부존량을 파악하기 위해 본 연구를 수행하였다. 연구 수행에는1560개 열물성 자료(밀도, 비열, 열전도도), 353개 지표 지열류량 자료, 180개 열생산율 자료와 54개의 지표온도 자료가 사용되었다. 우리나라의 지표에서부터 1 km 깊이 간격별로 5 km 깊이까지 지열에너지 부존량을 산출한 결과 지표에서 부터 5 km 깊이까지의 추출 가능한 지열에너지의 총 부존량은 $1.01{\times}10^{23}$ J로 산출되었다. 지열에너지 부존량을 Toe(석유환산톤) 로 환산하면 $2.40{\times}10^{12}$ Toe 가 된다. 추출한 지열에너지 자원의 2%를 사용한다고 가정 했을때 약 480억 Toe 이다. 이는 2006년 우리나라 전체 1차 에너지 총 소비량(2.33억 Toe)을 고려 했을때 약 200년 동안 사용할 수 있는 양이다.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.03a
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• pp.85-85
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• 2011

화학적 혹은 생물학적인 방법으로 합성된 생분해성 고분자(biodegradable polymers)는 환경 문제와 인간의 생명 유지와 같은 인간 생활과 밀접한 관계가 있는 적용 분야로 인해 많은 관심을 받고 있으며, 국내 플라스틱의 폐기량만 해도 2003년을 기준으로 연간 4,000톤을 쉽게 넘고 있고 재활용되는 양은 전체의 1/3 수준이며, 나머지 2/3는 소각되거나 매립되고 있다. 폴리에스테르계 생분해성 섬유는 "미생물이 분비하는 효소로, 분해 가능한 화학합성 섬유"로서, 미생물이 분비하는 가수분해 효소에 의해 고분자 쇄가 절단, 저분자량 화합물이 돼 미생물의 체내로 흡수되며, 이것이 미생물의 체내에서 효소작용에 의해 산화탄소와 물로 분해되는 섬유로 정의된다. 생분해성 고분자 중 화학합성 고분자인 지방족 폴리에스테르계 생분해성 고분자는 특히 환경 산업으로부터 많은 관심을 받고 있으며, 이러한 결정성 폴리에스테르계 고분자의 물성은 고분자의 결정화도 뿐만 아니라, 압력, 온도 등에 의해서 변할 수 있는 결정 구조에 의해 크게 영향을 받는다. 생분해성 섬유는 실용화가 이미 시작됐고, 다용도화와 수요 확대를 위해 많은 연구소와 대학, 기업들이 연구개발을 진행하고 있으며, 향후 석유자원이 고갈된다는 것은 명백한 사실이므로 이에 따라 화석자원의 절약과 유효 이용을 위해서라도 바이오 베이스 폴리머를 주원료로 한생분해성 섬유의 개발은 매우 중요한 의미를 갖는다. 본 연구에서는 합성섬유 중에서 75%의 비중을 차지하는 폴리에스테르를 대체 가능한 고내열생분해성 폴리에스테르계 직물을 제조하여 범용 폴리에스테르와 염색온도에 대한 염색성을 고찰하였다. 염색온도($100^{\circ}C$, $110^{\circ}C$, $120^{\circ}C$, $130^{\circ}C$)별, 3종의 분산염료의 농도(0.25,0.5,1.0,2.0%o.w.f)별 Build-up성 및 균염성을 비교하였으며, 염색 시료의 견뢰도를 평가하였다.

• The Journal of the Korea Contents Association
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• v.12 no.12
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• pp.25-34
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• 2012

Due to the development of wireless devices such as smart-phone and internet, a lot of linguistic resources actively are opened in each area of expertise. Also, various systems using semantic web technologies are developing for determining whether such information are useful or not. In order to build these systems, the processes of data collection and natural language processing are necessary. But, there is few systems to use of integrating software and data required those processes. In this paper, we propose the system, uLAMP, integrating software and data related to natural language processing. In terms of economics, the cost can be reduced by preventing duplicated implementation and data collection. On the other hand, data and software usability are increasing in terms of management aspects. In addition, for the evaluation of uLAMP usability and effectiveness, user survey was conducted. Through this evaluation, the advantages of the currentness of data and the ease of use are found.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.25 no.1
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• pp.9-18
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• 2012

The BIM called information modeling is used by tool not only it will simply be appearing the image and can save the information. Recently, there is a lot of case that improves the construction productivity by using the BIM during the life cycle of bridge from order to management. Although we already recognize the advantage of BIM, it is a careful phase to use the BIM. Therefore, We made the BIM for bridge, evaluated the possibility that can build the object used in the civil engineer, studied about the utility, the improvement in order to use the BIM properly. As a result, the BIM can recycle the information by using parametric model and attribute the efficiency and accuracy on drawing and calculating the quantity. The BIM is able to help productivity increase by using the builded model after we spend the effort building a model in early stage.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.445-448
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• 2008

It is essential that concrete component is made up with aggregate, cement and water. But today, Public concern is increasing of a variety structure and ocean environmental, resource recycle. Also, According to heat of hydration rising, Concrete is make a causative of concrete-crack. Concrete-crack cause a falling-off in quality of concrete. consequently, High-performance concrete is evaluated by concrete material properties and carbonation resistance with different admixture(fixing fly-ash 20%), granulated blast furnace slag replacement ratio (30%, 45%) different W/B (26%, 30%, 34%) and XRD(X-ray Diffraction) analysis.

• Resources Recycling
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• v.17 no.4
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• pp.21-29
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• 2008

Waste shell powder was added to the high density polyethylene(HDPE), and resultant mechanical properties and flame retardancy were analyzed in terms of shell content. Compatibilizer(PE-g-MA) was used to enhance the mechanical properties of the prepared HDPE/shell composites, and several flame retardant agents($Al_2O_3$, $Sb_2O_3$) were utilized to improve flame retardancy. Addition of the compatibilizer resulted in an improved mechanical properties due to the increased interfacial bonding between HDPE matrix and shell powder. In the case of impact strength, it even reached to the impact strength of pure HDPE. Also the addition of the flame retardant agents did not exhibit mechanical property decrease. UL-94 flammability test on the prepared HDPE/shell composites indicated that at 40wt% of shell only inclusion, time to ignite the flame and the total time of flame duration increased. When flame retardant agents mixed with shell powder were added to the HDPE matrix, improved flame retardancy was observed. Generally, flame retardancy effect of $Al_2O_3$ was better than $Sb_2O_3$. UL-94 V-0 classification was observed for the specimens with $Al_2O_3$ and compatibilizer at more than 40wt% shell, and also for specimens with $Sb_2O_3$ and compatibilizer at all shell content.