• Journal of Nutrition and Health
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• 제49권1호
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• pp.51-58
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• 2016

본 연구에서는 체리와 로메인 중 저장 시 저장 기간 및 저장 온도, 저장 온도의 변동폭에 따른 항산화 성분과 항산화 영양소의 보존율을 분석하고자 하였으며 총 폴리페놀, 총 플라보노이드, 총 항산화능, DPPH 소거능, 비타민 C 함유량을 분석하였다. 저장 조건은 온도와 저장 온도 변동폭에 따라 세 개의 조건에서 실험을 진행하였다. 체리는 9일 동안 저장 후 실험하였고, 로메인은 7일 동안 저장 후 실험하였다. 실험 결과, 로메인과 체리 시료 모두에서 수분 보유량은 $0.7{\pm}0.6^{\circ}C$에서 가장 높았다. 체리의 경우 $0.7{\pm}0.6^{\circ}C$에서 TAC의 함량 및 플라보노이드 함량이 유의적으로 높았으며 (p < 0.05), 로메인의 경우, 비타민 C 함량이 $0.7{\pm}0.6^{\circ}C$에서 유의적으로 높게 유지되었다 (p < 0.05). DPPH 활성은 $0.7{\pm}0.6^{\circ}C$ 저장시 유의적으로 높게 유지되었으며, $0.7{\pm}0.6^{\circ}C>4.7{\pm}1.4^{\circ}C>3.5{\pm}2.8^{\circ}C$의 순서로 활성이 저하되었다.

• 대한안전경영과학회지
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• 제7권4호
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• pp.229-248
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• 2005

The purpose of this study is to identify the best firing condition for Celadon, which is one of the famous traditional pottery to represent Korean culture, by minimizing energy consumption, cutting firing time, shortening the time of processing ceramic making, in order to, save energy as well as to protect the potters' health. Most Korean potter starts their reduction from $950^{\circ}C$ to change kiln atmosphere. However on this study, reduction have started from $950^{\circ}C\;to\;1200^{\circ}C$ by increasing $50^{\circ}C$ at a time. Then the results are analyzed to be compared to previous Celadon, in colors, chroma, and brightness. As a results, it is found, that the best temperature for starting reduction is $1100^{\circ}C$, when chroma and brightness values to meet same with previous celadon. Therefore the best condition could be made by starting the reduction on $1100^{\circ}C$ to fire celadon, which would have shorten 2 hours of firing process and, at the same time, it could have saved the energy by 12%.

• 생물환경조절학회지
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• 제7권2호
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• pp.139-143
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• 1998

지중가온시설을 이용한 고구마뿌리혹선충(Meloidogyne incognita Chitwood) 방제를 위하여 지하 20cm 깊이의 최저지온을 각각 30. 40, $50^{\circ}C$ 가온구 및 관행의 무지중가온구로 설정하고 담수구와 무담수구로 나누어 8월 1일부터 8월 5일까지 5일간 가온한 결과, 담수구의 경우 지온 4$0^{\circ}C$에서 5일간, 무담수구의경우 지온 $50^{\circ}C$에 5일간 지중가온처리한 구에서 생존한 유충이 발견되지 않아 선충밀도를 경제적 피해수준 이하로 유지할 수 있을 것으로 사료되었다. 지중가온으로 토양내 OM. P$_2$ $O_{5}$, Ca, Mg함량과 EC는 시험전 토양에 비하여 감소하였는데, 특히 담수처리에서 EC가 현저히 저하하였다.

• 한국해양공학회지
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• 제5권2호
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• pp.207-207
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• 1991

The crack length measurements by electrical potential(EP) method for 1% Cr-Mo-V and 12%Cr steel of 0.5T-CT specimen were performed at $500^{\circ}C, 600^{\circ}C 700^{\circ}C$, and an applicability of stress intensity factor($K_I$), net section stress($\sigma_{net}$), $C^*$-ingegral and $C_t$ parameter was studied to measure creep crack growth rate(da/dt) with side groove and without side groove under static and cyclic loading condition. The experimental result could be summarized as follows: 1) Crack measurement by EP method was available and coincided with the Johnson,s analytical equation. 2) da/dt by $K_I$ and $\sigma_{net}$ was not adequate because of the wide scatter band according to load and temperature, but $C^*$-integral, except for transition region, was adequate. 3) $C_t$ parameter showed the best fitted line through total creep region without relating with both temperature and load condition. 4) Under the cyclic loading condition, $C_t$ parameter was proper to extimate da/dt. And it was shown that da/dt for 1% Cr-Mo V steel under the static condition(R=1) was 1.16 times faster than the case under cyclic loading(R=0), and for 12% Cr steel, 1.43 times.

• 한국해양공학회지
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• 제5권2호
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• pp.67-75
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• 1991

The crack length measurements by electrical potential(EP) method for 1% Cr-Mo-V and 12%Cr steel of 0.5T-CT specimen were performed at $500^{\circ}C, 600^{\circ}C 700^{\circ}C$, and an applicability of stress intensity factor($K_I$), net section stress($\sigma_{net}$), $C^*$-ingegral and $C_t$ parameter was studied to measure creep crack growth rate(da/dt) with side groove and without side groove under static and cyclic loading condition. The experimental result could be summarized as follows: 1) Crack measurement by EP method was available and coincided with the Johnson, s analytical equation. 2) da/dt by $K_I$ and $\sigma_{net}$ was not adequate because of the wide scatter band according to load and temperature, but $C^*$-integral, except for transition region, was adequate. 3) $C_t$ parameter showed the best fitted line through total creep region without relating with both temperature and load condition. 4) Under the cyclic loading condition, $C_t$ parameter was proper to extimate da/dt. And it was shown that da/dt for 1% Cr-Mo V steel under the static condition(R=1) was 1.16 times faster than the case under cyclic loading(R=0), and for 12% Cr steel, 1.43 times.

• 한국축산식품학회지
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• 제18권2호
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• pp.115-124
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• 1998

This study was carried out investigate hygienic conditions of domestic packing plant for export and the shelf-life by Japanese standards. vacuum packaged chilled port loins provided by five packers(A, B, C, D and E) were transported to Japan in the same condition, Four packers(A, B, C adn d) produced the samples as hygienic as possible and one packer produced loins in the traditional hygienic condition, In TTC(2,3,5-triphenyl tetrazolium chloride) test all samples showed the negative reaction from the date of the quarantine(14 days after slaughtering) to 50 days The numbers of total plate count(TPC) of A, B, C and D packers that were below 108CFU/g until 50 days were accepted by Japanese Standards but TPC of E packer was over 107CFU/g at 30 days. VBN values increased sig-nificantly(P<0.01) in samples of A,B and D packers in the samples of C packer and E packer at 5% and 0.1% level respectively. The pH values of the vacuum packaged chilled pork for export at 14 days after slaughtering were 5.43∼6.00 In sensory evaluation, A, B, C and D packers which improved hygi-enic condition produced the products with good color and appearance. low drip until 40 days storage at $0^{\circ}C$ But as the storage time increase off-flavor occured at 40days in A and D packer and at 50days in B and C packer. In conclusion according to the above results of microbiological physicochemical and sensory evalution the edible periods of Korean vacuum package chilled porks may be estimated to 40∼50 days for the packers who improved hygienic condition and the shelf lives were calculated as 32∼40 days from edible period by a factor of 0.8(safety coefficient) while that of the pork from E packer which was produced in the traditional hygienic condition was estimated to 30 days after slaughtering at $0^{\circ}C$ Therefore the shelf-life of the pork of E packer would be only 24 days.

• 한국농공학회지
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• 제28권3호
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• pp.99-106
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• 1986

This study was carried out to investigate the effects of moisture content, temperature, C/N ratio and pH of the sewage sludge mixed with hulle and sawdusts for making compost under aerobic condition and to improve the defect of the structure of experimental equipment heat lose and handling method. and obtained results were as follows 1.The temperature was reached 73$^{\circ}$ C around 50 hours fermentation in the condition of 0.8 L/min. of air and 60.4% of moisture content. and favorable moisture content of initial condition ranged from 50 to 65% 2.The temperature near bottom of the batch composter was decreased due to evaporate water vapor and lose the heat produced during aeration. and it is required to be improved. 3.The temperature in the batch composter from the center to the inside wall surface was gradually decreased. the temperatures of the points located in r=9cm and the wall surface were 4$^{\circ}$ C and 6$^{\circ}$ C respectively. and therefore it is required to be insulated. 4. The maximum C02 production was obtained as 7.3% per volume in the temperature of 63$^{\circ}$C at the moisture content of 60% 5.The temperature range of active microbes growth was found to be as 20$^{\circ}$C to 40$^{\circ}$C in the case of mesophiles and 50$^{\circ}$C to 65$^{\circ}$C in the case of thermophiles due to increase and decrease C02 production. 6.C/N ratio after decomposition was 1.3 to 2.6 smaller than that of initial one due to increase the amount of nitrogen. The more C/N ratio increased. the less the reaction velocity decresed. The optimum of it as found to be 30. 7.pH values after decomposition were slightly increased than that of initial ones. The reaction velocity was decreased at acid and alkall condition. Therefore it is neseseary to neutralize the medium to improve the reaction.

• Composites Research
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• 제26권6호
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• pp.337-342
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• 2013

나노입자를 이용하여 강화 효과를 높이기 위해서는 고분자 기지 내부의 균일한 분산 상태를 확보하여야 한다. 또한 균일분산 조건 확보 후 균일 분산상태를 증명할 평가자료가 필요하다. 본 연구는 에폭시 수지와 SiC 나노입자를 혼합한 SiC/에폭시 복합 수지를 제조할 경우 커패시턴스 측정법을 이용한 강화재 분산도 예측 연구를 진행하였다. 커패시턴스는 전기용량을 의미하며 측정 재료의 내부 전하량과 비례한다. 기존 에폭시 수지에 비해 나노 SiC 입자를 함유할 경우 전하량이 증가되는 이론을 바탕으로 구간별 커패시턴스 측정에 따른 분산도 평가를 진행하고, 커패시턴스 분산도 예측방법에 대한 타당성을 FE-SEM과 물리적 강도 증가 방법으로 평가하였다. 소니케이션 분산 방법과 교반기 분산 방법을 이용하여 분산 방법에 따른 SiC 나노입자 분산도 상태를 비교하였다. 인장강도와 커패시턴스 간의 상관관계가 있었으며, 파단면에 대한 비교를 할 때 분산성 향상에 대한 차이를 확인할 수 있었다.

• 대한기계학회논문집A
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• 제33권9호
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• pp.949-956
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• 2009

The C(t)-integral describes amplitude of stress and strain rate field near a tip of stationary crack under transient creep condition. Thus the C(t)-integral is a key parameter for the high-temperature crack assessment. Estimation formulae for C(t)-integral of the cracked component operating under mechanical load alone have been provided for decades. However, high temperature structures usually work under combined mechanical and thermal load. And no investigation has provided quantitative estimates for the C(t)-integral under combined mechanical and thermal load. In this study, 3-dimensional finite element analyses were conducted to calculate the C(t)-integral of elastic-creep material under combined mechanical and thermal load. As a result, redistribution time for the crack under combined mechanical and thermal load is re-defined through FE analyses to quantify the C(t)-integral. Estimates of C(t)-integral using this proposed redistribution time agree well with FE analyses results.

• 한국토양비료학회지
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• 제19권2호
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• pp.153-156
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• 1986

수온 및 지온변화에 단독(單獨) 또는 혼합(混合) 서식(棲息)하는 좀개구리밥, 붕어마름 및 조류등(藻類等)이 미치는 영향(影響)을 구명(究明)코자 1/200a 대형무저토관(大型無底土管)에서 조사연구(調査硏究)한 결과(結果)는 다음과 같았다. 1. 담수토양(湛水土壤)의 일중(日中) 최고수온 및 지온은 좀개구리밥 서식지(棲息地)가 무서식지(無棲息地)보다 $1{\sim}3^{\circ}C$정도(程度) 낮았으나 최저수온 및 지온은 같거나 $0.5^{\circ}C$정도(程度) 높았다. 2. 담수토양(湛水土壤)의 천기별(天氣別) 수온 및 지온은 좀개구리밥 서식지(棲息地)가 무서식지(無棲息地)보다 맑은 날은 $0.1{\sim}0.3^{\circ}C$ 낮았으나 구름 강우(降雨) 개임시(時)는 $0.1{\sim}0.4^{\circ}C$정도(程度) 높았다. 3. 조류서식(藻類棲息) 담수토양(湛水土壤)의 수온 및 지온은 무서식지(無棲息地)보다 $0.3{\sim}1.0^{\circ}C$ 높아 조류(藻類)에 의한 보온효과가 認定되었다. 4. 잡초서식(雜草棲息) 형태별(形態別) 수온 및 지온 보존(保存) 효과는 붕어마름 단독서식(單獨棲息)>혼합서식(混合棲息)>분개구리밥 단독서식(單獨棲息)>무서식(無棲息) 순(順)으로 높았다.