• Journal of the Korean Wood Science and Technology
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• v.37 no.3
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• pp.255-264
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• 2009

To evaluate the effects of chemical pretreatments of lignocellulosic biomass on enzymatic hydrolysis process, Populus euramericana was pretreated for 1 hr with 1% sulfuric acid ($H_2SO_4$) at $150^{\circ}C$ and 1% sodium hydroxide (NaOH) at $160^{\circ}C$, respectively. Before the enzymatic hydrolysis, each pretreated sample was subjected to drying process and thus finally divided into four subgroups; dried or non-dried acid pretreated samples and dried or non-dried alkali pretreated samples and chemical and physical properties of them were analyzed. Biomass degradation by acid pretreatment was determined to 6% higher compared to alkali pretreatment. By the action of acid ca. 24.5% of biomass was dissolved into solution, while alkali degraded ca. 18.6% of biomass. However, reverse results were observed in delignification rates, in which alkali pretreatment released 2% more lignin fragment from biomass to the solution than acid pretreatment. Unexpectedly, samples after both pretreatments were determined to somewhat higher crystallinity than untreated samples. This result may be explained by selective disrupture of amorphous region in cellulose during pretreatments, thus the cellulose crystallinity seems to be accumulated in the pretreated samples. SEM images revealed that pretreated samples showed relative rough and partly cracked surfaces due to the decomposition of components, but the image of acid pretreated samples which were dried was similar to that of the control. In pore size distribution, dried acid pretreated samples were similar to the control, while that in alkali pretreated samples was gradually increased as pore diameter increased. The pore volume which increased by acid pretreatment rapidly decreased by drying process. Alkali pretreatment was much more effective on enzymatic digestibility than acid pretreatment. The sample after alkali pretreatment was enzymatically hydrolyzed up to 45.8%, while only 26.9% of acid pretreated sample was digested at the same condition. The high digestibility of the sample was also influenced to the yields of monomeric sugars during enzymatic hydrolysis. In addition, drying process of pretreated samples affected detrimentally not only to digestibility but also to the yields of monomeric sugars.

• Journal of Biosystems Engineering
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• v.11 no.2
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• pp.92-102
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• 1986

• Proceedings of the Korean Society of Tobacco Science Conference
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• 1999.05a
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• pp.18-18
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• 1999

• 물만먹고자라요
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• no.21
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• pp.41-43
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• 2008

콩나물의 원료로 이용되는 나물콩은 종자의 활성과 품질이 매우 중요하다. 수확시기, 탈곡, 건조과정 및 저장방법 등에 따라서 종자의 품질과 발아력에 큰 차이가 있다.

• The Korean Journal of Food And Nutrition
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• v.16 no.4
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• pp.334-339
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• 2003

To increase the utilization of citron, citron juice that is by-product of citron tea was spray dried and freeze dried. Cyclodextrin(CD) was used as wall material to stabilize during drying. The physiochemical properties of citron juice were as follows: water content of 82.3%, pH of 2.45, and there were little different in two kinds of drying or CD added in different ratio. Citric acid, malic acid, succinic acid and lactic acid were detected in all of the samples. Spray and freeze-drying increased markedly yellowness compared to that of citron juice. Heat stability was reduced by both of two kinds of drying, and CD 15% was more decreased than CD 10%. Water uptake by freeze-drying was somewhat higher than that of spray-drying. When sensory properties of original citron juice was compared with those of spray and freeze dried, freeze drying with 10% of cyclodextrin was evaluated as superior to citron juice or other drying conditions.

• Journal of the Korean Wood Science and Technology
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• v.18 no.3
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• pp.34-41
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• 1990

본 연구는 CCA로 방부(防腐)처리된 Lodgepole pine 각재(角材)의 재건조(再乾燥)시 고온건조법(高溫乾燥法)의 적용이 건조속도(乾燥速度) 및 건조결함(乾燥缺陷)의 발생에 어떻게 영향하는가를 고찰하고자 수행되었다. 고온건조시 건조속도는 통당(通常) 열기건조(熱氣乾燥)시보다 약(約) 2.5배 증가되었으며, 방부처리재의 재건조 속도는 처리전(前)의 전건조속도보다 약간 감소됨을 보였다. 표면할열(表面割裂)의 발생정도(程度)은 전건조시의 경우, 고온건조시 보다 심(甚)하였으나 재건조시에는 건조방법간에 큰 차이가 없었다. 방부제의 침투(浸透)를 도모(圖謀)하기 위하여 자상(自傷)처리(Incising)된 각재의 경우에는 재건조시 절개부(切開部)의 연장(延長)에 의해 할렬의 정도가 증가됨을 보였다. 뒤틀림(Warping)의 발생정도는 고온건조시가 통상 열기건조에 비해 심하지 않았으며, 전(全) 건조과정을 통하여 발생된 뒤틀림은 WWPA가 정(定)해놓은 Lodgepole pine 2등급(等級)(No. 2 grade)의 뒤틀림 허용치(許容値)의 범위내(範圍內)에 있음을 보였다. 결론적(結論的)으로, 고온건조시 증가되는 건조속도와 건조재의 질(質)에 큰 영향을 주지않는 범위내에서 발생되는 건조결함을 고려할 때, Lodgepole pine의 전건조및 CCA 처리후 재건조를 위해 큰 문제없이 고온건조법이 적용될 수 있음을 보였다.

• Korean Journal of Food Science and Technology
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• v.34 no.5
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• pp.805-810
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• 2002

Development of tenderizer using domestic fruits was studied. Kiwifruit was dried using various methods, and the quality of kiwifruit powder was observed during 12 week storage. Frozen kiwifruit was prepared in paste, dice, and whole flesh. After drying, paste-type kiwifruit showed 2.0 and 1.3 times higher proteolytic activity than dice and whole flesh kiwifruits, respectively. Nine hour of hot-air drying or 46 h of freeze-drying eliminated more than 90% of water from kiwifruit, during which discoloring of kiwifruit occurred. Freeze-dried powder showed 6.6 times higher yield and proteolytic activity, and resulted in almost no discolorization than those of air-dried powder. Addition of bulking agent affected the quality of hot air-dried kiwifruit powder, except color, resulting in $3.2{\sim}3.6$ times higher proteolytic activity than that without bulking agent, which is comparable to 60% of the initial freeze-dried powder content. Moisture content of kiwifruit powder with bulking agent sustained consistently during 12 week storage, whereas proteolytic activity decreased for the first 4 weeks. Freeze-drying is a preferable method to produce kiwifruit powder for tenderizer, although hot air-drying with bulking agent treatment is more economical.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.7
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• pp.1-8
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• 2019

The primary purposes of this study are to understand a fundamental effects of electro-deposition on reinforcing steel in saturated Ca(OH)2 electrolyte, and evaluate the corrosion rates of rebars under cyclic 3wt.%NaCl immersion and dry corrosion environment. The three cement mortar specimens with cover thickness 5, 10 and 30mm, were prepared in the experiment. To monitor the corrosion rates of rebars in mortar, the three cement mortar specimens were exposed to 110 wet-drying cycles(8-hour-immersion in 3wt.%NaCl and 16-hour-drying in a room temperature) in the laboratory. During the wet-dry cycles, the polarization resistance, Rp, and solution resistance, Rs, were continuously measured. The instantaneous corrosion rates of rebars on the effect of electro-depositing with sat. Ca(OH)2 electrolyte were estimated from obtained R-1p and degrees of wetness were estimated from Rs values. From the experimental results, the corrosion rates of rebars were greatly accelerated by wet/dry cycles. During the mortars exposed to drying condition, the large increases in the corrosion rates were showed at all rebar surfaces in three mortar specimen, attributed from the accelerated reduction rates of dissolved oxygen in drying process. However, the corrosion rates on rebar surface electrochemically deposited with sat. Ca(OH)2 electrolyte showed the clear decreases, caused by calcium deposits in the porous rust layer.

• Journal of Adhesion and Interface
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• v.17 no.2
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• pp.62-66
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• 2016

The curing processes of waterborne adhesives are in general undergone by using hot-air dryer. The hot-air dryer curing the adhesives with heat has a disadvantage of requiring high temperature over $100^{\circ}C$ as well as curing time as long as 20 min. When it comes to the heat control, high temperature open disturbs the adhesion of substrates by extremely lowering the viscosity of the adhesives. Furthermore, the humidity resulting from the drying process makes the curing condition irregularly. In this report, dehumidifying membrane dryer was used in order to keep the curing process same by removing humidity caused by the evaporation of water during the drying process, and to shorten the curing time. Here, we compared the peel strength of attached substrates in the dehumidifying membrane dryer to find out appropriate curing condition and confirm the effects of the dehumidifying membrane.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1996.04a
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• pp.559-563
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• 1996

선박 건조는 선체를 수십에서 많게는 이백여개에 블럭으로 분활하여 각 블럭에 해당하는 원자재를 처리 가공한 후 소조립, 중조립, 그리고 대조립의 과정을 거쳐 블럭으로 완성하여 이들 블럭을 정해진 순서에 맞추어 탑재하는 과정을 거치면서 기타 공정을 완료하여 마지막으로 진수에 이르게 된다. 본 연구에서는 선박 건조 과정에서 탑재 공정 계획을 위한 블럭의 접속 관계를 체계적으로 확립하여 탑재 순서를 생성하는 방법론을 제시하고 이러한 방법론을 바탕으로 초기 탑재 네트워크을 생성 방안을 제시한다.