• Transactions on Electrical and Electronic Materials
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• 제14권1호
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• pp.28-31
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• 2013

A volcano shaped gated Si-FEA (silicon field emitter array) was simply fabricated using sputtering as a gate electrode deposition and lift-off for the removal of the oxide mask, respectively. Due to the limited step coverage of well-controlled sputtering and the high aspect ratio in Si dry etch caused by high RF power, it was possible to obtain Si FEAs with a stable volcano shaped gate structure and to realize the restriction of gate leakage current in field emission characteristics. For 100 tip arrays and 625 tip arrays, gate leakage currents were restricted to less than 1% of the anode current in spite of the volcano-shaped gate structure. It was also possible to keep the emitters stable without any failure between the Si cathode and gate electrode in field emission for a long time.

• 보존과학회지
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• 제5권2호
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• pp.15-24
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• 1996

Th)s study was carried out of the historical characters and textile coservations for Mrs. Danha Lee's Wonsam. As the textile material was silk, dry cleaning method was suggested. The solvents for dry cleaning were n-hexane, n-decane, and benzene. During the second cleaning process, the dry soap(HI-TECH, 120:1, volume ratio) was added to the mixed solvents. The reaction's temparature was $20^{\circ}C$, and the reaction's time was 30 minuutes. It seemed to be a gift for hot from the Royal Family because of the attachment of pheonlx hungbae. This wonsam was decorated symmetrically by gold weaving yarn, the basic fabric was green silk satin with glorius letters and floral patterns. It was made on the 17th C and the oldest thing among them.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 1998년도 공동 심포지엄 및 추계학술발표회
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• pp.216-220
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• 1998

Experimental studies were carried out to investigate water diffusion in unsaturated compacted bentonite for a landfill of hazardous wastes. Water content distributions were measured and water diffusion coefficients were determined when the dry densities of compacted bentonite were in the range of 1.4 - 1.8 g/㎤. Resaturation times were also calculated to analyze the ability of the compacted bentonite to retard water movement. The results obtained were as follows: Diffusion model described properly the water migration in unsaturated compacted bentonite. Water diffusion coefficients ranged from 4.30$\times$10$^{-6}$ $\textrm{cm}^2$/sec to 1.93$\times$10$^{-6}$ $\textrm{cm}^2$/sec, and decreased with increasing the dry density. The dry density of compacted bentonite was found to be an important factor to control the resaturation time by water. This study suggests that the domestic compacted bentonite should be a good barrier material against water movement in a landfill of hazardous wastes.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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• pp.229-232
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• 2003

Recently, it is increased on the concern for the reuse of waste concrete because of the shortage of natural aggregate and the increase of waste concrete. And recycled coarse aggregate is used variously, but the existing wet method producted recycled fine aggregate has problems like the high price facilities, the long time progress of the work and recycled fine aggregate of poor. The aim of this study is to investigate the possibility of the method of dry producted high qualities recycled fine aggregate. The results of this study have shown that the possibility of the method of dry is certificated as the qualities of recycled fine aggregate satisfied the KS and the compressive strength of mortar was similar to plain.

• 한국산업융합학회 논문집
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• 제2권2호
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• pp.69-72
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• 1999

The aim of this study is to enhance the abrasion of the hydrolyzed polyethylene terephthalate(PET) fabrics by using microwave energy. In other to achieve the aforementioned objectives, PET fabrics were hydrolyzed in NaOH solution by using abrasion method such as dipping, microwave-dipping, pad steam-dry, and pad microwave-dry, and then abrasion of the hydrolyzed PET fabrics was calculated and investigated. As a result obtained form this study, the abrasion of the hydrolyzed PET fabrics is directly proportional to hydrolyzed time and NaOH concentration. And also, microwave-dipping method and pad microwave-dry method showed remarkable abrasion effect than the others.

• Food Science and Biotechnology
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• 제18권1호
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• pp.150-156
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• 2009

In this study, Staphylococcus carnosus isolated from traditional sucuk (Turkish dry-fermented sausage) was used in combination with Lactobacillus plantarum as a lactic culture in sucuk production. Sucuk produced with only L. plantarum was evaluated as a control group. Microbiological, physicochemical, and volatile profile characteristics of sucuk samples were investigated during ripening. In both sausages with S. carnosus and control group, pH value decreased to below 5.0 at the $3^{rd}$ day. In all samples, Aw value decreased as the ripening time progressed. Sausages with S. carnosus showed the higher nonprotein nitrogen (NPN) value than control group. However, the highest mean value for thiobarbituric acid reactive substances (TBARS) was observed in control group. Enterobacteriaceae dropped to undetectable levels at the $3^{rd}$ day in both groups. S. carnosus increased approximately 1 log unit within the first 3 days of the fermentation. In the presence of S. carnosus, significant changes were observed in only a few volatile compounds.

• 한국수산과학회지
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• 제30권6호
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• pp.923-928
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• 1997

The occurrence of butyltin compounds in the seawater and sediment of Masan Bay was investigated. The concentrations were in the range of $ND-0.059{\mu}g/\ell$ for tributyltin (TBT), $ND-0.091{\mu}g/\ell$ for dibutyltin (DBT) and $ND-0.720{\mu}g/\ell$ for monobutyltin (MBT) in the seawater, and $ND-0.233{\mu}g\;TBT/g.dry$, $ND-0.197{\mu}g-DBT/g.dry$ and $ND-0.684{\mu}g-MBT/g.dry$ in the sediment. Among the butyltin compounds, the major component in the seawater was MBT, while the predominant species in the sediment changed with time. The tributyltin concentrations in the sediment are approximately three orders of magnitude greater than the associated water column levels. Sediment/water partition coefficients (K) of TBT were between $0.6\times10^3\;and\;5.0\times10^3$.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2001년도 추계종합학술대회
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• pp.214-217
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• 2001

마이크로웨이브 연속 건조기는 전자파를 사용하여 피건조물의 내부로부터 건조시키는 가열장치로서 주로 ISM 주파수 대역(915MHz와 2450MHz을 사용한다 피건조물의 연속적인 가열을 위해서는 건조체가 통과하는 입ㆍ출구가 개방되어야한다. 이러한 마이크로웨이브 연속 건조기는 응용 분야가 무한함에도 불구하고 균일 가열, 개방 공간 작업과 같은 기술적 제약으로 인해 가정용 마이크로웨이브 오븐 정도의 수준에 머물고 있는 상태이다. 본 논문에서는 2450MHz의 마이크로웨이브 주파수에서 동작하는 연속 건조기에 적합한 구조 설계를 위해 유한 차분 시간 영역(FDTD : Finite-Difference Time-Domain)법을 이용하여 건조기 내부와 외부의 전자계 분포를 해석하였다.

• 한국의류학회지
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• 제23권5호
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• pp.757-763
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• 1999

The burn-out technique is used to result in the velvet cloth being patterned in open and solid areas by carbonize the cellulose fiber. It is examined how to burn out the cellulose part of the velvet without damage of the other part. The print paste indalca solution is mixed with sodium hydrogensulfate and lycerine and then screen-printed on the back side of the velvet. The effects of process conditions such as concentration of sodium hydrogensulfate dry heat fixation temperature and time pull no. and glycerine contents on the properties of ground farics were investigated. The yellowness index and the breaking load of silk ground fabrics afected by the process conditions especially concentration of sodium hydrogensulfate dry heat fixation temperature.

• 무역학회지
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• 제47권5호
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• pp.21-37
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• 2022

Baltic Dry Index (BDI) is difficult to forecast because of the high volatility and complexity. To improve the BDI forecasting ability, this study apply Bayesian variable selection method with a large number of predictors. Our estimation results based on the BDI and all predictors from January 2000 to September 2021 indicate that the out-of-sample prediction ability of the ADL model with the variable selection is superior to that of the AR model in terms of point and density forecasting. We also find that critical predictors for the BDI change over forecasts horizon. The lagged BDI are being selected as an key predictor at all forecasts horizon, but commodity price, the clarksea index, and interest rates have additional information to predict BDI at mid-term horizon. This implies that time variations of predictors should be considered to predict the BDI.