• Journal of Ocean Engineering and Technology
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• v.23 no.2
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• pp.92-97
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• 2009

In order to export aircraft components or substructures, it is necessary to get a certification from the main company for the components or an airworthiness certification from the FAA. In Korea, those processes are performed by a small number of private companies for aircraft components. However, airworthiness certification has never been done in the company. To export an assembled aircraft, whether small or large, it is obligatory to get a certification for the aircraft being exported. Currently, the Korean government is trying to get BASA agreement in a few years. For a mid-size company, it is easier to get the NADCAP audit process for the supply of aircraft components to the main company. In this paper, the overall process of aircraft certification is discussed and airworthiness certification is treated for export aircraft. Moreover, the NADCAP audit process is described in detail by introducing example parts made of composite material. This detailed process would be very helpful to a small or mid-size company that wants to develop and deliver aircraft components to foreign companies.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.1
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• pp.75-84
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• 2015

This study was conducted to investigate the effects of high temperature and drought on growth performance, photosynthetic parameters and photosynthetic pigment contents of Liriodendron tulipifera L. seedlings. The seedlings were grown in controlled-environment growth chambers with combinations of four temperature ($-3^{\circ}C$, $0^{\circ}C$, $+3^{\circ}C$, $+6^{\circ}C$; based on the monthly average for 30 years in Korea) and two water status (control, drought). Temperature rise increased growth, total dry weight and leaf area in all water status. Also photosynthetic rate, dark respiration, stomatal conductance and transpiration rate increased with increasing temperature. In contrast, growth and photosynthetic parameters of L. tulipifera seedlings were lower in $-3^{\circ}C$ than $0^{\circ}C$. But temperature rise decreased water use efficiency in all water status. Temperature rise increased photosynthetic pigment contents of leaf. Also chlorophyll a/b ratio increased with increasing temperature. In conclusion, the elevated temperature lead to causes growth increase through the increase of energy production by higher photosynthetic rate during a growth period of L. tulipifera seedlings.

• Proceedings of the Ginseng society Conference
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• 2003.05a
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• pp.48-48
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• 2003

• Korean Journal of Plant Resources
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• v.14 no.2
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• pp.175-181
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• 2001

Dormancy of intact zoysiagrass seeds hinders its seed propagation in which presowing seed treatment must be done to overcome it. The study was done to remodel the presowing treatments of zoysiagrass seeds by determining the treatment effects of seedcoat softening, prechilling, drying and combined light treatment with them or during germination stage. Seedcoat softening with different chemicals (NaOH 20%, KOH 20%, $H_2SO_4\;8M, acetone 20%) and periods (10, 30, 60 min.), prechilling with different periods at 3$^{\circ}C$, and drying with 4 hours at 35$^{\circ}C$ was done. Light sources were also applied with 660 nm red LED light, commercial fluorescent and incandescent light and darkness. Germination test was done in alternative day and night temperature of 35 and 2$0^{\circ}C$ to check the daily germination rates. With seeds treated with NaOH 20% for 30 minutes, red and incandescent light showing similar responses inclined their germination rates compared to dark conditions. Drying resulted in its higher rate than non-drying but fluorescent light treatment forced during drying more enhanced the rate than red light. While mean germination rate considering all the seedcoat softening treatment periods was the greatest in $H_2SO_4$ in comparison with NaOH, KOH and acetone, NaOH treatment for 30 minutes showed the best rate among the all the treatment levels. In the conditions of sowing them to no-mulching field, presowing treatment procedure of zoysiagrass seeds was remodeled: the seedcoat softening treatment with NaOH 20% for 30 minutes was done, washed, and chilled at 3$^{\circ}C$ for 2 weeks before dried under 4 hour fluorescent light illumination at 35$^{\circ}C$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.3
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• pp.169-172
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• 2003

Intact seeds of burcucumber (Sicyos angulatus L.) are not nearly germinated so that the farmers remove their arils before sowing. The study was carried out to measure the effort of aging, chilling, washing, chemical treatment, drying, and their sequential treatments on the germination of ones with arils and the seedling emergence. The seeds extruding over 1mm of their radicles and the seedlings with fully expanded cotyledons were counted daily for calculating the germination and the seedling emergence rates. Seedcoat softening using 10% NaOH solution somewhat enhanced their germination rate of the intact seeds harvested in the current year, but aging treatment done on 6 days at $45^{\circ}C$ after NaOH treatment increased the germination rate more than only NaOH treatment. A day washing after the NaOH treatment and a day chilling after the washing increasingly elevated the rates as well. Irrigation of 0.2% $\textrm{KNO}_3$ solution, moreover, showed the greatest germination rate of the priming treatments done during all the 7 day chilling. Drying the seeds after the combined treatment of chilling and priming more inclined the germination rate than nondrying ones, but red light treated during 24 hour desiccation was more effective in the germination rate increment than dark condition. The seeds done the sequential treatments of aging, NaOH, washing, combining chilling and priming and drying under red light illumination were germinated up to 80% but seedlings were emerged to 60%, lower than ones removed their arils.

• Journal of Bio-Environment Control
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• v.15 no.4
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• pp.377-384
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• 2006

This study was conducted to investigate the effects of chemical application and amout of soil moisture on low temperature stress of cucumber seedling under the greenhouse conditions. When chilling treatments ($2^{\circ}C$) were begun at 07:00AM, survival rates of seedlings of two conditions; -0.3 bar and -5.5 bar were 28.3% and 83.3% respectively. But when chilling treatments were begun at 6:00PM - even the soil moisture condition was -0.3 bar - the survival rate was above the 87%. When reducing the soil moisture from -0.3 bar to -9.0 bar, ABA content in leaf was inc.eased by 6.5fo1d. Spraying of abscisc acid (ABA) before or after the chilling significantly increased the survival rates of seedlings, decreased the amounts of leaking electrolytes and prevented the yield reductions. ABA application on the soil before the chilling appeared to be more effective than the application after the chilling with foliar spray. Spraying of ABA ($10^{-5}M$), urea (0.2%) or $KH_2PO_4$ was effective in counteracting the low temperature, which causes growth deterioration and yield reduction in cucumbers.

• Food Science of Animal Resources
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• v.25 no.1
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• pp.92-97
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• 2005

This study was carried out to determine the storage, cryotolerance, heat and drying resistance, when Lactobacillus acidophilus CT 01 isolated from preweaned piglet feces growing at suboptimal temperature. L. acidophilus CT 01 suboptimal temperature incubated for 48 hours had the slowest growth rate at 22℃ but the highest viable cell number after 36 hours at 22℃, with 1.3×10/sup 9/ CFU/mL. In case of 4 and 20℃ storage, the suboptimal temperature incubated groups had a viability higher than the control (p<0.01). The cryotolerance of suboptimal temperature incubated L. acidophilus CT 01 was a higher than the control (p<0.01). When L. acidophilus CT 01 was heat treated at 60℃ for 15 minutes and 30 minutes, the suboptimal temperature incubated L. acidophilus CT 01 at 22℃ had a viability higher more than the control (p<0.01). L. acidophilus CT 01 incubated suboptimal temperature was inoculated by 30% to the carrier, and dried at 50℃ for 12 hours had the highest viability in the suboptimal temperature incubated L. acidophilus CT 01 at 28℃.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.07a
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• pp.182-187
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• 2002

국내 저온저장고의 주류를 이루고 있는 컨테이너 박스형 저온저장고의 문제점은 재래식 제어방식으로 인한 성능저하 외에도 자체 구조적인 설계상의 문제점을 가지고 있다 이러한 구조적인 문제점을 열거하면 다음과 같다. 첫째, 한 축 방향에 설치되어있는 유니트 쿨러에서 토출되는 냉기에 의해 저장고 내의 공기를 냉각하는 형태이기 때문에 냉기의 분포가 고르지 못하여 균일한 온도 분포를 이루기 어렵다는 단점을 가지고있다. 둘째, 한 축 방향에서 토출되는 냉기가 맞은 편 벽면까지 도달해야 하기 때문에 풍속이 강해야 하며 이로 인해 저장 청과물이 냉해를 쉽게 입고 심한 증산작용에 의해 쉽게 표면건조나 중량감소를 가져온다. 셋째, 천장부와 측벽부가 90$^{\circ}$의 경사각을 가지고 있어 공기의 유동이 원활하지 못하여 에디현상으로 인한 온도나 풍속의 불균일 구간을 피해서 청과물을 저장해야 하기 때문에 그만큼 버려지는 공간이 많아 비경제적이다. 넷째, 위와 같은 문제점들 때문에 중ㆍ대형의 저온저장고를 컨테이너 박스형으로 설비 할 경우 보다 심한 온도 불균일과 냉기유동 분포를 보여 경제적인 손실이 더 커지게 되는 악순환을 낳게된다. 이에 따라 본 연구에서는 국내 저온저장고의 구조적인 설계상의 문제점을 인식하고 이를 해결하고자 3차원 CFD 시뮬레이션을 이용하여 저온저장고의 새로운 모델을 설계하였다. 이론 바탕으로 직접 저온저장고의 시작기를 개발하여 저장고 내부의 역 유동과 난류유통을 해석하였다. (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.136-137
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• 2001

젤리형 해조면류의 유통 및 저장 중에 면가락이 건조되거나 동결하였을 경우 수분이 조직으로부터 분리되어 면의 굵기가 가늘어지면서 딱딱해져 식용하기에 부적당하게 된다. 따라서 이러한 문제를 해결하기 위해서는 먼저 포장을 할 때 적당량의 보존수를 첨가하여 저온 유통을 하여야 한다. 보존수의 첨가 후 저온 유통이 잘 유지될 경우에는 저장 6개월까지는 품질안정성에 문제는 없다. (중략)

• Journal of Advanced Marine Engineering and Technology
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• v.34 no.4
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• pp.460-469
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• 2010

In spite of the global-class aquaculture and fishing technology of our country, the processing technologies are lags behind the other nations relatively. The processed marine products are mainly frozen foods, canned goods, salty food (fermented fish products), fish paste products (boiled fish paste), and we can see that the high-value dehydrated foods by drying are very few. These problems are considered to be caused directly by the lack of drying technologies. This paper is concerned to the experimental results of drying heat transfer characteristics for the green energy type vacuum dryer for the high quality sea foods production.