• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회 2차
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• pp.81-87
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• 2010

As enormous construction projects of land development are carried out around Korea, useful construction materials are needed to perform the construction projects. However, there are no more enough of fill and reclamation materials in our country. That is why the coal ash is expected to be utilized as an alternative material. Since the coal ash has the characteristics of a pozzolan and a selfhardening material, it is adjudged that coal ash has a great possibility to be used as a fill and reclamation material. In this study, grain size analysis, Atterberg limit test, and specific gravity test were performed to examine the physical characteristics of the coal ash about a self-hardening material before utilizing the coal ash in the construction. Compaction test, unconfined compression test were conducted to investigate the engineering characteristics according to mixture ratios of fly ash and bottom ash. As a result of the tests, it was confirmed that the mixing ratio 1:1 of fly ash and bottom ash is the most effective to use as a fill and reclamation material. If the mixture of coal ash is used as a backfill material with light weight around structure, it is expected to play a significant role in reducing earth pressure on the back of the structure. As described above, the coal ash should be considered as an alternative material of fill and reclamation materials since the result of the tests indicates that the coal ash is suitable to a useful material on the construction design.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1999년도 연약지반처리위원회 학술세미나
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• pp.23-35
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• 1999

Although the purpose of dredging in the past was merely as a means of lowering the water level, presently land reclamation from dredged fill is of greater interest. From an economical standpoint, due to the difficulties in acquiring landfill for coastal projects, there is a growing trend toward simply using easily obtainable marine clay for use as fill. But because the ground formed by dredged fill has but low strength and is accompanied by large settlements, it is important that the engineering characteristics be fully investigated. In order to use dredged Masan marine clays as fill material, the engineering characteristics have been studied in this paper.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2006년도 춘계 학술발표회 논문집
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• pp.818-823
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• 2006

In this study, the suitability of CFGD(concrete faced gravefill dam) was investigated by examining the strength and deformation characteristics of a gravelfill material, a CFGD main fill material, and comparing them with those of several rockfill dam materials. The gravelfill material exhibited similar strength and deformation properties to those of the main fill materials of existing stable large rockfill dams. Since not only CFGD has environmental and economic advantages over CFRD, but its main fill material compares favorably with those of the existing stable CFRDs, CFGD may be the best choice when natural gravel materials are abundant in the vicinity of the dam construction location.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 춘계 학술발표회
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• pp.1032-1039
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• 2010

Based on the proven feasibility of bottom ash and tire shred-soil mixtures as lightweight fill materials, tire shred-bottom ash mixtures were suggested as a new lightweight fill material to replace the conventional construction material with bottom ash. Therefore, we carried out the laboratory test, field compaction test and performance test of large scale embankment in order to evaluate their suitability for the use of lightweight fill materials in the before studies. We could verified that the ash, tire-shred and the mixture are able to be the useful materials as light fill materials. In this study, we built real scale embankment with RBA(Reclamated Bottom Ash), TRBA(Tire shred-Reclamated Bottom Ash mixture), WS(Weathered Soil), BA(Bottom Ash screened by 5mm sieve) for monitoring the behavior such as settlement, lateral displacement and water content change. Furthermore, we are examining the ground water quality in the surrounding area of the test embankment.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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• pp.886-895
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• 1993

Experimental were conducted to obtain information on the effect of airflow rates and bed depths on the resistance of coffee cherries and coffee beans available locally (Coffea Liberica). The airflow used were in the range of 0.06 to 0.6 cu. m/s-sq.m. The moisture content of the coffee cherries ranged from 10 % to 50% (wet basis) and that of coffee beans ranged from 12% to 30% )wet basis). Two methods of filling were used i.e. loose fill and packed fill. Pressure drops across the material bed in a vertical column were measured at several depths using inclined manometer. The pressure drop increased directly with air flow rate as well as bed depths. The effects of air flowrates and moisture contents on the resistance in terms of pressure drip per unit bed depth were analysed. The pressure drop per unit depth across the material bed varied slightly due to different depth. The resistance to airflow decreased with the increase in moisture content for loose fill. However, the effect of moisture content is not apparent for packed fill.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 춘계 학술발표회
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• pp.679-686
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• 2010

Mechanical characteristics of bottom ash produced in coal-fired power plant are investigated to utilize as light-weight fill materials. Triaxial compression test, water retention test, and unsaturated direct shear test were conducted for weathered soil (WS), reclaimed bottom ash (RBA), and screened bottom ash (BA). RBA had larger frictional angle and lower effective cohesion than those of WS. Water retention charactersitics of RBA and BA existed within distributions of soil-water characteristic curves for domestic weathered soils. Unsaturated shear strength of RBA was similar to that of WS at matric suctions of 50 kPa and 100 kPa. As a conclusion, bottom ash can be used as fill materials to replace the conventional construction materials by.

• 한국농공학회논문집
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• 제54권3호
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• pp.47-54
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• 2012

As a large construction such as highway, dam, reclaimed land etc. increase in number more and more, large amount of fill materials are required. It is needed to utilize a gypsum which is a by-product yielded from chemical plants, as fill materials. Though some studies have been conducted to know a engineering characteristic of gypsum, it is not certain that water contents were checked at $45^{\circ}C$ dry oven. This study proposed that water contents must be measured at $45^{\circ}C$ dry condition because gypsum is changed to other types as a dry temperature. As the results obtained by compaction tests, it is found that moisture of gypsum in compaction must be within -5.0~2.5 % O.M.C (optimal moisture content).

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.93-94
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• 2005

Cu metallization using electrochemical plating(ECP) has played an important role in back end of line(BEOL) interconnect formation. In this work, we studied the optimized copper thickness using Bottom-up Gap-fill in Cu ECP, which is closely related with the pattern dependencies in Cu ECP and Cu dual damascene process at 0.13 ${\mu}m$ technology node. In order to select an optimized Cu ECP thickness, we examined Cu ECP bulge, Cu CMP dishing and electrical properties of via hole and line trench over dual damascene patterned wafers split into different ECP Cu thickness.

• 대한토목학회논문집
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• 제29권1C호
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• pp.21-31
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• 2009

기존의 연구에서 이미 경량성토재료로서 적용된 바 있는 저회(Bottom Ash), 폐타이어-흙 혼합토의 성능을 토대로 하여, 전통적인 성토재료인 흙 대신 저회를 활용하는 새로운 경량성토재료를 제안한 바 있다. 이어서 이 연구에서는 저회-폐타이어 혼합토의 경량성토재료로서의 적용성을 평가하기 위해 현장다짐시험과 실대형 성토 모형실험을 수행하여 기존의 성토재료인 풍화토만으로 조성된 성토구조물과 저회-폐타이어 혼합토로 조성한 성토구조물에 대한 침하, 토압, 지지력, 진동저감효과 등을 평가하였다. 그 결과 토압 및 진동은 저감되는 효과를 보였으며, 정동적 하중에 따른 침하거동은 두 재료(풍화토 단면, 저회-폐타이어 혼합재료)에서 유사하게 평가되었다.

• Journal of electromagnetic engineering and science
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• 제12권1호
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• pp.101-106
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• 2012

In this study, we investigated the effect of groove pattern and gap-fill with lossy materials at 15 GHz frequency of Ku-band. We used Epoxy/MWCNT composite materials as gap-fill materials. Although epoxy does not have an absorbance capability, epoxy added conductive fillers, which are multi-walled carbon nanotubes (MWCNT), can function as radar absorbing material. Specimens were fabricated with different MWCNT mass fractions (0, 0.5, 1.0, 2.0 wt%) and their permittivity in the Ku-band was measured using the waveguide technique. We investigated the effect of gap-fill on monostatic RCS by calculating RCS with and without gap-fill. For arbitrarily chosen thickness and experimentally obtained relative permittivity, we chose the relative permittivity of MWCNT at 2 wt% (${\varepsilon}_r$=8.8-j2.4), which was the lowest reflection coefficient for given thickness of 3.3 mm at V-pol. and $80^{\circ}$ incident angle. We also checked the monostatic RCS and the field intensity inside the groove channel. In the case of H-pol, gap-fill was not affected by the monostatic RCS and magnitude was similar with or without gap-fill. However, in the case of V-pol, gap-fill effectively reduced the monostatic RCS. The field intensity inside the groove channel reveals that different RCS behaviors depend on the wave polarizations.