• 유기물자원화
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• 제11권1호
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• pp.84-89
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• 2003

본 연구는 음식폐기물과 하수슬러지의 병합처리를 위한 음식폐기물 전처리시설을 평가하고 그 활용방안을 모색하기 위하여 수행되었다. 본 연구에서 이용한 음식폐기물 전처리시설은 저장, 선별분쇄, 농축의 순으로 구성되어 있으며, 하수처리장 방류수를 희석수로 이용하여 선별분쇄시 파쇄를 용이하게 하고 염분농도의 희석효과도 가져올 수 있었다. 파쇄된 음식폐기물의 입자는 대부분 2mm 이하로 하수슬러지와 혼합하여 혐기성소화시 효율이 높은 것으로 조사되었다. 기존 하수슬러지 처리시 발생되는 가스발생량은 0.8톤/일(메탄 0.5톤/일)로 매우 낮았으나 음식폐기물과의 병합처리후에는 3.5톤/일(메탄 2.3톤/일)의 소화가스가 발생하는 것으로 조사되었다. 탈수슬러지의 발생량 또한 기존 11.2톤/일에 비해 21.2톤/일로 증가하지만 하수슬러지에 비해 유기물 함량이 높으므로 재활용 가치가 높을 것으로 판단된다. 따라서 음식폐기물 전처리시설의 적절한 활용을 통해 기존 하수처리시설과의 연계 처리가 가능할 것으로 판단된다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 제26회 KOSCO SYMPOSIUM 논문집
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• pp.103-108
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• 2003

The control of flame shapes in a laminar pre-mixed flame has been experimentally investigated for propane/air pre-mixed laminar flames. Flames of different size and shapes are observed with heated wires or by controlling the equivalence ratio and flow rate of a mixture. The characteristics of the partitioning of a flame or the merge of flames are analyzed and explained by considering the balance between laminar flame speed and upstream mixture velocity. A combustor might be sized down while maintaining its heat production rate the same by partitioning a flame established in it. When the equivalence ratio of mixture is decreased, individual flames are merged together and the upstream mixture velocity can be practically decreased on a nozzle having opening ratio less than unity. As a result, the flame shape is to he adjusted until the newly established balanced condition is satisfied, and then. the stable combustion can be achieved again.

• Asian-Australasian Journal of Animal Sciences
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• 제26권1호
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• pp.134-142
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• 2013

The effect of modified atmosphere packaging (MAP; 30% $CO_2$+70% $N_2$ or 100% $N_2$) and an additive mixture (500 ppm rosemary extract, 3,000 ppm sodium acetate and 1,500 ppm calcium lactate) on the quality of pre-cooked hamburger patties during storage at $5^{\circ}C$ for 14 d was evaluated. The addition of the additive mixture reduced aerobic and anaerobic bacteria counts in both 30% $CO_2$-MAP (30% $CO_2$+70% $N_2$) and 100% $N_2$-MAP (p<0.05). The 30% $CO_2$-MAP was more effective to suppress the microbial growth than 100% $N_2$-MAP, moreover the 30% $CO_2$-MAP combined with additive mixture resulted in the lowest bacterial counts. The hamburger patties with additive mixture showed lower CIE $L^*$ and CIE $a^*$, and higher CIE $b^*$ than those with no additive mixture. The 30% $CO_2$-MAP tended to decrease the TBARS during storage regardless of the addition of additives. The use of 30% $CO_2$-MAP in combination with additives mixture was effective for maintaining the quality and extending the shelf-life of pre-cooked hamburger patties.

• 신재생에너지
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• 제1권2호
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• pp.60-72
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• 2005

The effect of alkaline pre-treatment on the solubilization of waste activated sludge(WAS) was investigated, and the biodegradability of WAS, pretreated WAS, [PWAS], food waste and two types of mixture were estimated by biochemical methane potential [BMP] test at $35^{\circ}C$. The biodegradability of PWAS and mixture waste were significantly improved due to the effect of alkaline hydrolysis of WAS. An alkaline pre-treatment was identified to be one of the useful pre-treatment for improving biodegradability of WAS and mixture waste. In high-rate anaerobic co-digestion system coordinate with an alkaline pre-treatment in process, the digesters were operated at the HRT of 5, 7, 10 and 13 days with a mixture of FW $50\%\;and\;PWAS\;50\%,\;$In term of $CH_4$ content, VS removal and specific methane production [SMP] which are the parameters in the performance of digester, the optimum operating condition was found to be a HRT of 7 days and a OLR of 4.20g/L-day with the highest SMP of 0.340 L $CH_4/g$ VS.

• International Journal of Automotive Technology
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• 제7권1호
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• pp.17-23
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• 2006

An experimental study was carried out to obtain the fundamental data about the effect of sub-chamber on pre-mixture combustion. A eve (constant volume combustor) divided into a sub-chamber and a main chamber was used in this experiment. The volume of the sub-chamber was varid trom $0.45\%$ to $1.4\%$ about the whole combustion chamber. The sub-chamber has twelve narrow radial passage holes and a spark plug to ignite the pre-mixture. As the ignition occurs in the sub-chamber by a spark discharge, burned and unburned gas including a great number of radicals is injected into the main chamber, then the multi-point ignition occurs in the main chamber. The combustion pressure is measured to calculate the burning velocity mainly as a function of the sub-chamber volume, the diameter of the passage holes, and the equivalence ratio. In the case of RI (radical ignition) methods, the overall burning time became very short and the maximum burning pressure was slightly increased as compared with that of SI (spark ignition) method. The optimum design value of the sub-chamber is near 0.11 $cm^{-l}$ in the ratio of total area of holes to the sub-chamber volume.

• 한국의류산업학회지
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• 제15권5호
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• pp.808-814
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• 2013

In this study, The mixture of three kinds of pre-treatment agents, Carboxymethyl cellulose sodium salt(CMC), Sodium alginate and Dextrin, have been prepared for the better coloration of digital textile printing. To get sharpness of outline during digital printing process, the optimal formulation is the CMC and Sodium alginate mixture 1:1 ratio by volume. Cyan, Yellow, and Black colours are excellent on the Sodium alginate mixtures. But, Magenta is excellent in the CMC and Dextrin mixture. Sharpness and printability are closely related to viscosity of the mixture. The most optimal sharpness of outline achieved with a consideration of coloring, and field operations account for production when the viscosity of the mixed pre-treatment agent approximately is 10~13 cSt. Change in shade and staining of wash fastness for all the treated samples with the mixtures rated 4-5 grade. Both dry rubbing fastness to shade change and staining are good in the treated samples, whereas wet rubbing fastness rated 2-3 grade. To improve wet rubbing fastness, the Sodium alginate and Dextrine mixture, which rated 3-4 grade for Black color, is applicable. With exception of 3 rating to black color, Light fastness is 4 rating for the remaining three colors in the regardless of treatment condition and mixing of the pre-treatment agent. Dry cleaning fastness of all samples are also 4-5 rating.

• Communications for Statistical Applications and Methods
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• 제21권6호
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• pp.501-512
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• 2014

Stylized facts on asset return are fat-tail, asymmetry, volatility clustering and structure changes. This paper simultaneously captures these characteristics by introducing a multi-regime models: Finite mixture distribution and regime switching GARCH model. Analyzing the daily KOSPI return from $4^{th}$ January 2000 to $30^{th}$ June 2014, we find that a two-component mixture of t distribution is a good candidate to describe the shape of the KOSPI return from unconditional and conditional perspectives. Empirical results suggest that the equality assumption on the shape parameter of t distribution yields better discrimination of heterogeneity component in return data. We report the strong regime-dependent characteristics in volatility dynamics with high persistence and asymmetry by employing a regime switching GJR-GARCH model with t innovation model. Compared to two sub-samples, Pre-Crisis (January 2003 ~ December 2007) and Post-Crisis (January 2010 ~ June 2014), we find that the degree of persistence in the Pre-Crisis is higher than in the Post-Crisis along with a strong asymmetry in the low-volatility (high-volatility) regime during the Pre-Crisis (Post-Crisis).

• 한국분무공학회지
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• 제22권3호
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• pp.116-121
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• 2017

Pre-combustion chamber type indirect diesel engines have different combustion characteristics compared with those of common rail direct injection engine. The CONVERGE, specific engine CFD program, was used to simulate hollow cone spray model and combustion. The air-fuel mixture flow propagating from pre-combustion chamber to cylinder was concentrated at top half and center of the pre-combustion chamber throat. Stronger mixture flow was formed at smaller and longer throat cases. As a result, thermal efficiency and fuel consumption were improved for modified throat shape and the soot emission was also reduced.

• Journal of Internet Technology
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• 제21권3호
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• pp.841-847
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• 2020

In this paper, a novel technique that improves the performance of generalized mixture decomposition algorithm (GMDA) based on pre-training phase unwrapping. From the investigation of the GMDA scheme, it was discovered that the conventional GMDA technique cannot fully consider phase unwrapping, because the estimated inter-channel phase difference (IPD) slope is initialized randomly. To avoid this phenomenon, the proposed GMDA approach initialized the IPD slope from the data of low-frequency bins. Experimental results show that comparing to the conventional GMDA technique, the proposed GMDA technique based on pre-training phase unwrapping obtains a lower estimation error. When integrated into a source localization system, the result of source localization is improved.

• 대한한의학회지
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• 제28권1호통권69호
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• pp.198-210
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• 2007

Objectives : Nitric oxide(NO) is a reactive free radical and a messenger molecule in many physiological functions. However, excessive release NO of induces neurotoxicity. We investigated whether a mixture of red ginseng and paeonia radix prossesses a protective effect against sodium nitroprusside(SNP)-induced apoptosis in the human neuroblastoma cell line SK-N-MC. Methods : We performed 3- (4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay, 4,6-diamidino-2-phenylindole(DAPD) staining, terminal deoxynucleotidyl transferase(TdT)-mediated dUTP nick end labeling(TUNEL)assay, DNA fragmentation assay, reverse transcription-polymerase chain reaction(RT-PCR), Western blot analysis, and caspase-3 enzyme activity assay in SK-N-HFC cells. Result : MTT assay showed that SNP treatment significantly reduced the viabilities of cells and that pre-treatment with the red ginseng and paeonia radix mixture alleviated SNP-induced cytotoxicity. The cells treated with SNP exhibited several apoptotic features, while those pre-treated fir 1 h with the mixture of red ginseng and paeonia radix 1 h prior to SNP expose showed reduced apoptotic features. In addition, the cells pre-treated with the red ginseng and paeonia radix mixture for 1 h prior to SNP expose increased bel-2 expressions, decreased Bax expressions, and decreased caspase-3 enzyme activity. Conclusions : These results show that the red ginseng and paeonia radix mixture exerts a protective effect against SNP-induced apoptosis in SK-N-MC cells.