• 한국식품저장유통학회지
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• 제22권1호
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• pp.1-11
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• 2015

ANOVA 분석을 통해 건조온도와 건조시간이 열풍건조와 냉풍건조의 중요변수임을 알 수 있었으며 복분자의 반건조를 위해서는 열풍건조의 경우 $65.8^{\circ}C$, 4.3시간이 적당하였고 냉풍건조의 경우 비슷한 정도의 건조수분함량까지 28.2시간이 걸렸다. 그러나 건조온도가 높아지면 vitamin C와 ellagic acid의 함량이 줄어드는 등 품질적 열화가 심하게 나타났다. 또한 생리활성물질들은 냉풍건조에서 전반적으로 더 잘 보존 되었으며 총폴리페놀의 함량에서는 더욱 그러하였다. 따라서 냉풍건조방법은 고품질의 반건조 복분자 제조에 적합한 건조방법이며 최적 건조조건은 $21.3^{\circ}C$, 28.2시간으로 나타났다.

• 한국식품저장유통학회지
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• 제24권5호
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• pp.658-665
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• 2017

식용 및 약용으로 이용되고 있는 함초를 이용한 고부가가치 제품개발을 위해, 동결건조, 열풍건조, 음건한 함초의 ethanol추출물을 조제하여 건조방법에 따른 성분 변화, 항산화 및 항혈전 활성 변화를 평가하였다. 동결건조, 열풍건조 및 음건 시료의 ethanol 추출효율은 각각 14.4, 13.2, 11.9%를 나타내어 동결건조시 수율이 음건에 비해 1.2배 높았다. 성분 분석결과, 동결건조 시료의 total polyphenol 함량은 4.6 mg/g으로 열풍건조 및 음건 시료보다 높았으며, total flavonoid 함량은 건조방법과 무관하게 4.2-4.4 mg/g을 나타내었다. 반면 총당 함량은 동결건조에서 가장 높게 나타났으며, 음건 시료는 동결건조 시료에 비해 53% 수준을 나타내었다. 환원당의 경우 열풍건조시료에서 가장 높게 나타났으며, 음건시료에 비해 3.3배 높게 나타났다. 항산화 활성 평가결과, 동결건조, 열풍건조 시료에서는 유사한 항산화 활성이 나타났으나, 음건 시료의 경우 환원력과 nitrite 소거능은 유의적으로 감소되었다. 항응고 활성의 경우, 모든 건조 시료에서 농도 의존적인 우수한 항응고 활성을 나타내었으며, 특히 열풍건조 시료에서 강력한 TT 및 aPTT 연장 활성을 나타내었다. 인간 혈소판에 대한 응집저해 활성과 적혈구 용혈활성은 건조방법에 따른 유의적인 변화는 나타나지 않았다. 본 연구결과는 함초의 유용 기능성 유지를 위해 열풍건조 및 동결건조가 필요하며, 특히 함초의 항혈전 활성을 이용하는 기능성 식품을 제조하고자 하는 경우 열풍건조를 이용하는 것이 경제적이면서 효과적임을 제시하고 있다.

• 한국환경과학회지
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• 제24권6호
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• pp.769-776
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• 2015

This study was conducted to determine the effects of high temperature and deficit irrigation on growth and yield of hot pepper. Hot pepper was subjected to four irrigation treatments: fully irrigation (FI), 10, 20, and 30 days deficit irrigation (DI) combination with high temperature treatment. Control plants were grown natural environment and conventional culture methods. The plant height treated with high temperature was significantly higher than that of control plant. At FI combination with high temperature treatment, growth parameters such as stem diameter, leaf area, fresh and dry weight were the greatest. The yield was the greatest (2,036 kg/10a) under control, DI combination with high temperature treatment decreased by approximately 42% compare with FI combination with high temperature treatment. The number of abnormal fruits was approximately 38/plant under control, which was the smallest and that of 30 days DI combination with high temperature was higher 3.3 times compare with control. Flower abscission and calcium deficiency induced by DI treatments, especially those physiological disorder promoted by increasing DI treatments period. Results indicated that yield of hot pepper reduced by DI treatments, these results suggest that the growers should irrigate to proper soil moisture for preventing reduction of total fruit yield.

• Journal of the Korean Wood Science and Technology
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• 제16권1호
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• pp.3-8
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• 1988

This study was carried out to examine the effect of pretreatment of veneer with aluminum sulfate solution for the manufacture of the kapur plywood on the reduction of urea resin spread. The results were as follows: 1. Specific gravities of plywoods made of the kapur veneers ranged from 0.83 to 0.84 and their moisture contents based on air dry weight showed from 10.6% to 11.4%. These met the Korean Industrial Standards. 2. In the case of dry shear strength for the 3rd class plywood, 40% reduction- spread met K S as well as normal urea resin spread. pH of the aluminum sulfate solution gave better result at pH 4.5 and pH 6 than at pH 3. For the manufacture of the 2nd class plywood, hot and cold water-wet shear strength show the best results at the following conditions; such as 20% reduction spread, pH 4.5 of aluminum sulfate solution and all veneer treatment.

• 한국응용과학기술학회지
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• 제27권4호
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• pp.437-444
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• 2010

Dry Process(natural drying, hot-air drying, oil fry drying), optimized mixture ratio and the condition of carbonization was carried out in order to improve the product durability develop eco-friendly solid fuel mixing food waste and paper sludge. As a result of the experiment, oil fry drying process was the fastest method for drying food waste and paper sludge mixture that contains 80% water inside, and the optimized mixture ratio to minimize the generating concentration of chlorine gas against caloric value of mixture ratio was 7:3. Additionally proper temperature of product carbonization was about $200^{\circ}C$ and shown increasing product durability through the carbonization. Therefore, the pelletized solid fuel be shaped diameter around 0.5cm, length 2cm under which was pulverized and molded using 7:3 mixture of food waste, and paper sludge was the eco-friendly solid fuel possible to be industrialized which is consist of chlorine concentration of below 2.0wt% and the lowest caloric value of over 5,000kcal/kg. In conclusion, this developing manufacturing process of the solid fuel can be interpreted to contribute alternative energy development in accordance with low carbon and green growth era.

• 한국조리학회지
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• 제24권1호
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• pp.105-113
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• 2018

In this study, optimized pre-treatment conditions were investigated to improve the quality of gochujang apple jangachi. The moisture content was decreased by 14% in 60% sugar solution and 17% in 30% salt solution during 12 hours. On the one hand, in the case of dry sugar and salt method, moisture content was decreased rapidly by 20% and 24%, respectively during 12 hours. Compared with the sugar and salt solution method, the dry sugar and salt method was more effective in reducing moisture content during 12 hours. In the case of osmotic dehydration of the apple parts in the dry sugar method, the moisture content of the flesh, flesh including peel, and peel of apple decreased by 23%, 20%, and 16%, respectively during 6 hours. However, in the dry salt method, the moisture content of the flesh, flesh including peel, and peel of apple decreased by 19%, 12% and 13%, respectively during 2 hours. During this time, the pH tended to decrease, regardless of the presence of sugar and salt. Total acidity was slightly increased in the case of salt. In hot air drying after osmotic dehydration, the moisture content of flesh including peel of apple decreased from 64% and 67% to 31% and 27%, respectively at 90 minutes, and from 64% and 67% to 11% and 18% at 150 minutes, respectively. The moisture content of the peel decreased from 51% to 10% at 120 minutes. As a result of the sensory evaluation, the overall acceptance of the flesh and flesh including peel was highly evaluated, resultantly, the products were considered to be suitable for the production of gochujang apple jangachi.

• 한국식품저장유통학회지
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• 제14권6호
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• pp.591-597
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• 2007

고추의 건조 중 발생하는 품질저하를 억제시키고 사용편의성을 증대시키기 위하여 열풍건조기를 이용한 반건조고추를 제조하였다. 반건조 고추는 통고추, 2단세절 고추, 4단세절 고추로 제조한 후 $65^{\circ}C$에서 연속건조를 실시하여 표면색도, ASTA 값, 비타민 C, capsanthin, capsaicinoids 및 유리당 함량을 조사하였다. 생홍고추의 수분함량은 85% 수준이었고, 대조구로서 건조고추의 수분함량은 15%내외로 제조하였다. 통고추에 비하여 2단세절 고추, 4단세절 고추 및 8단세절 고추의 경우 건조시간이 약 66.7%, 79.2%, 80.8% 감소되었다. 표면색도와 ASTA 값의 경우 건조시간이 증가할수록 ASTA 값이 낮아지는 경향을 나타내었으며, 표면색도 중 L 값은 높아지고, a 및 b 값은 낮아지는 경향을 나타내었다. 제조 방법별 반건조고추와 건조고추를 비교한 결과 비타민 C 함량, capsanthin 함량, capsaicinoids 함량, 유리당 함량에서 모두 반건조 고추가 높은 것으로 나타났다. capsaicin 함량의 경우 반건조고추가 건조고추에 비하여 약 8% 높은 것으로 나타났으며, dihydrocapsaicin 함량은 약 $13{\sim}17%$ 증가하였다. capsanthin 함량의 경우 2단세절 및 4단세절 반건조 고추가 건조고추에 비하여 약 $12{\sim}16%$ 증가하였으며, 유리당 함량은 건조시간이 증가할수록 그 함량은 낮아지는 경향이었으나, 4단세절 반건조고추의 glucose 함량의 경우에는 초기값과 유의적인 차이를 나타내지 않았다. 비타민 C 함량을 측정한 결과, 2단세절 및 4단세절 반건조 고추가 건조고추에 비하여 약 $40{\sim}76%$ 높게 유지되는 것으로 나타났다. 따라서 반건조고추는 건조 고추에 비하여 우수한 품질특성을 가지는 것으로 판단되며, 특히 반건조고추 제조 시 4단세절로 절단 후 수분함량 50% 내외 수준으로 제조하는 것이 적절할 것으로 판단된다.

• 설비공학논문집
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• 제17권4호
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• pp.285-296
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• 2005

In order to reduce the compression power and to use the overall energy contained in LNG effectively, a combined cycle is devised and simulated. The combined cycle is composed of two cycles; one is an open cycle of liquid/solid carbon dioxide production cycle utilizing LNG cold energy in $CO_2$ condenser and the other is a closed cycle gas turbine which supplies power to the $CO_2$ cycle, utilizes LNG cold energy for lowering the compressor inlet temperature, and uses the heating value of LNG at the burner. The power consumed for the $CO_2$ cycle is investigated in terms of a production ratio of solid $CO_2$. The present study shows that much reduction in both $CO_2$ compression power (only $35\%$ of power used in conventional dry ice production cycle) and $CO_2$ condenser pressure could be achieved by utilizing LNG cold energy and that high cycle efficiency ($55.3\%$ at maximum power condition) in the gas turbine could be accomplished with the adoption of compressor inlet cooling and regenerator. Exergy analysis shows that irreversibility in the combined cycle increases linearly as a production ratio of solid $CO_2$ increases and most of the irreversibility occurs in the condenser and the heat exchanger for compressor inlet cooling. Hence, incoming LNG cold energy to the above components should be used more effectively.

• Journal of the Korean Wood Science and Technology
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• 제29권4호
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• pp.16-24
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• 2001

함수율은 목재의 효율적인 가공을 위한 기본적인 정보 중에서 가장 중요한 것의 하나이다. 그러나 기존의 열풍식 전건법으로는 수 시간에서 수일이 소요될 정도로 매우 긴 시간이 소요되므로 산업현장에서 적용하기에는 불편하다. 본 연구에서는 가정용 마이크로웨이브 오븐을 응용하여 수 분~수십 분내에 목재 시편의 함수율을 전건법에 의해 측정할 수 있는 기술을 개발하고자 하였다. 국산 3수종에 대하여 마이크로웨이브-전건실험을 수행한 결과 일반 열풍식 전건법에 비하여 전건시간을 1/7~1/10 수준으로 크게 줄일 수 있었고 일반 열풍식 전건법 과 비교하여 전건상태에서 0.1~0.2 g 정도의 편차만 나타내어 함수율 및 전건무게를 신속하고 정확하게 얻을 수 있도록 해주므로써 효율적인 목재건조를 수행하는데 도움이 될 것으로 기대된다.

• Tribology and Lubricants
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• 제17권4호
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• pp.312-320
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• 2001

In magnetic hard disk drives, higher areal recording density requires reduction of head-disk spacing. To overcome the increase of stiction associated with reduction of head-disk spacing, a padder slider, which adds pads to slider's air bearing surface, can be one of the practical solution for sub 20 nm flying height, and even for near contact recording. This study investigated the tribological characteristics of a padder slider. A padder slider took off slowly but showed less friction force than a normal slider. The hot/dry CSS test and drag test indicated that pad wear of a padder slider was negligible. The tribological performance of disk is an important factor to be considered. In particular, less carbon overcoat layer of the disk will result in higher stiction and wear in slider/disk interface. In conclusion, a padder slider shows encouraging tribological performances for practical use in HDD.