• Journal of Advanced Marine Engineering and Technology
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• 제17권4호
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• pp.100-106
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• 1993

A study on optimizing the friction welding of copper(C1100) to aluminium(A1050) for developing the electrical sleeve was experimentally carried out and also on real-time nondestructive evaluation of the friction weld quality (strength) was accomplished by acoustic emission technique. The results obtained are summarized as the following ; 1) The heating upset $U_1$(mm) or total upset U(mm) tends to increase according to the increase of heating time $t_1$(sec). The relations between $U_1$ and $t_1$ or U and $t_1$are computed as follows when n=2000rpm, $P_1$=4, $P_2$=8kgf/$mm^2$, and $t_2$=6sec. U=1.6$e^{0.39t_1}$ $U_1$=3.65$e^{0.25t_1}$. 2) It was notified that the proper welding conditions by considering on both strength with more than 100% joint effieciency and toughness are heating time of 1.5-2.25 sec under n=200rpm, $P_1$=4, $P_2$=8kgf/$mm^2$, $t_2$=6sec. 3) It was confirmed that both AE total counts(N, counts) and the weld tensile strength (${\sigma}$, kgf/$mm^2$) of the welded joints increase as the increase of heating time, respectively, the relations between N and $t_1$, ${\sigma}$ and $t_1$ are computed from data points by regression analysis using the least square method as follows in case of the above proper condition ; N=50108+23917(ln $t_1$)${\sigma}$$=11.85+2.06(ln $t_1$). 4) Both empirical and calcularated equations of relationship between .sigma. and N are very coincident with a high reliability, as the following in case of the above proper welding condition ; Calculated : ${\sigma}$=0.00008N+7.5 Empirical :${\sigma}$= $8.17e^{0.0000072N}$. 5) It was confirmed that the real-time nondestructive weld strength evaluation for friction welding of copper(C1100) to aluminium(A1050) could be possible by acoustic emission technique.

• 한국균학회지
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• 제40권4호
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• pp.210-214
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• 2012

시판되는 막걸리 3종을 $10^{\circ}C$와 $25^{\circ}C$에 저장하며 이화학적 특성과 미생물의 변화를 분석하였다. $10^{\circ}C$에서 저장한 막걸리의 에탄올 함량은 11일 동안 7.0%를 넘지 않았으며 pH는 3.12-3.99, 총산은 0.22-0.28%였으며 고형분 함량은 저장기간 동안 감소는 것으로 나타났다. $25^{\circ}C$에서 저장 한 막걸리의 에탄올 함량은 저장 9일에 7.0%를 초과하였으며 pH와 총산은 각각 3.96-4.17과 0.27-0.30%로 $10^{\circ}C$에 저장 한 막걸리 보다 높게 나타났으며 고형분 함량은 큰 폭으로 감소하였다. 저장 기간 동안의 효모수는 $10^{\circ}C$와 $25^{\circ}C$에 저장 시 각각 저장 3일과 1일에 $2.90-16.00{\times}10^7$ CFU/mL와 $1.12-29.40{\times}10^7$ CFU/mL로 최대치를 보였으며 세균수는 $25^{\circ}C$에 저장 한 막걸리가 $10^{\circ}C$에 저장한 막걸리에 비하여 높은 것으로 나타났다. 젖산균은 저장 3-7일 높게 나타났는데 $25^{\circ}C$에서 저장한 막걸리에서 $38.90-50.00{\times}10^7$ CFU/mL로 $10^{\circ}C$에 저장 한 막걸리에 비하여 더 높게 검출되었다. 기호도 검사 결과 $25^{\circ}C$에 저장 한 막걸리는 저장 1일 이후부터 5.0 이하의 점수를 보였으며 $10^{\circ}C$에 저장 한 막걸리는 저장 11일 후에도 4.9-5.2 수준을 나타내었다.

• 한국식품위생안전성학회지
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• 제25권1호
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• pp.73-78
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• 2010

영 유아용이유식, 견과류, 조미건어포류, 천연향신료, 건조과실류, 과 채가공품, 곡류가공품, 수산물가공품 등 국내 방사선 조사가 허용되지 않은 8품목에 대하여 PSL과 TL 분석법의 적용가능성을 검토하고 325건의 식품을 대상으로 방사선 조사여부 실태조사를 실시하였다. 선행 연구가 수행된 천연향신료, 과 채가공품 및 수산물가공품을 제외한 5개의 식품군에 대하여 PSL과 TL 시험법 적용 가능성 검토 결과, PSL의 경우 비조사구는 모두 700 count보다 낮아 음성 시료로 나타났고 1 kGy로 조사 시 중간 및 양성 시료로 확인되었다. TL 분석결과 비조사구는 모두 자연방사선에 의해서 $300^{\circ}C$ 부근에서 peak를 가지는 비 특이적 glow curve를 나타냈고 TL ratio는 0.1보다 낮게 나타나 음성 시료로 확인되었다. 1 kGy로 조사 시 TL ratio는 영 유아용이유식을 제외하고 모든 시료에서 0.1 이상으로 나타났으며 $150{\sim}250^{\circ}C$ 사이에서 peak가 나타나는 특이적 glow curve를 보여 확인 시험법으로 적용 가능하였다. 또한 영 유아용이유식은 2가지 이상의 원료가 혼합되어있어 TL ratio가 비록 0.1 이하지만 $150{\sim}250^{\circ}C$ 사이에서 peak가 나타나는 특이적 glow curve를 통해 조사 여부를 확인할 수 있었다. 국내 방사선 조사 허용 외 식품 8품목에 대하여 PSL과 TL 시험법의 적용가능성을 확인한 후 325건의 식품에 대하여 실태조사 결과, PSL 경우 15건에서 중간시료가 나타났으나 TL 분석 시 TL ratio가 0.1 이상이거나, $150{\sim}250^{\circ}C$ 부근에서 최대강도를 보이는 glow curve를 나타내는 양성시료는 없는 것으로 확인되었다.

• 한국식품저장유통학회지
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• 제20권1호
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• pp.30-36
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• 2013

본 연구는 대추형 방울토마토 유통에 있어 과병과 꽃받침을 포함하는 꼭지 유지와 제거에 따른 내부품질, 외관상 품질변화와 미생물상에 미치는 영향에 대하여 알아보고자 수행하였다. 적색기 대추형 방울토마토인 '베타티니' 품종을 대상으로 꼭지 유지 또는 제거 처리 후 $20^{\circ}C$에 12일간 저장하면서 호흡량, 중량감소율, 색도, 경도, 가용성고형물함량, 산도 등의 품질과 일반세균수, 대장균군, 곰팡이수 등의 미생물 변화를 관찰하였다. 저장 12일 동안 중량감소율은 꼭지를 제거한 대추형 방울토마토가 꼭지가 유지된 무처리보다 더욱 낮았다. 꼭지 제거 처리가 꼭지 유지에 비하여 호흡량이 낮게 유지되었으며 꼭지 제거된 상처부위에 새로운 조직이 형성되는 것을 형태학적으로 관찰하였다. 가용성고형물함량, 산도, 과피의 hue angle값은 저장 8일 후 감소하는 경향이었고 꼭지 유지/제거에 따른 유의적인 차이는 없었다. 꼭지에 일반세균수, 대장균군, 곰팡이수가 많아 저장 5일 이후 꼭지에 발생하는 곰팡이로 인한 저장병해가 꼭지 유지 대추형 방울토마토 유통 시 저장수명을 짧게 하는 요인이 되었다. 꼭지 제거 대추형 방울토마토의 저장기간은 약 8일이었으나 꼭지 유지 방울토마토는 약 6일로 관찰되어 대추형 방울토마토의 꼭지를 제거하고 유통하는 것이 저장성 향상에 적합한 것으로 판단된다.

• Natural Product Sciences
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• 제20권1호
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• pp.39-43
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• 2014

Papenfussiella kuromo (PK) is a marine plant and an abundant ecological resource for the future; it is found in almost 80% of the terrestrial biosphere. The aim of this study was to investigate the antibacterial activity of PK against methicillin-resistant Staphylococcus aureus (MRSA), multidrug-resistant pathogen. The minimum inhibitory concentrations (MICs) of PK hexane fraction (PKH) against 7 strains of MRSA ranged from 1.0 to 2.0 mg/mL. In the checkerboard dilution method, a synergistic effect of the PKH and the antibiotics (oxacillin and norfloxacin) was seen. PKH markedly reduced the MIC of each of the 4 antibiotics against MRSA. The time-kill assay showed that the synergistic activity of PKH and an antibiotic reduced the bacterial counts below the lowest detectable limit after 24 h. These findings suggest that PKH has antibacterial activity, and may be important baseline data in future extensive studies of living marine resources as a source of compounds active against MRSA.

• 한국식품조리과학회지
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• 제20권6호
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• pp.561-567
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• 2004

The purpose of this study was to investigate the effect of Paecilomyces japonica mycelia(PJM) on pH, titrable acidity and microbiological qualify of Jeungpyun(fermented rice cake). Jeungpyun prepared with $0\~\%$ of PJM stored at $5^{\circ}C\;and\;20^{\circ}C$ for 4 weeks and 7 days respectively. Before fermentation of Jeungpyun dough, viable cells of total bacterial counts(TBC), yeasts and lactic acid bacteria(LAB) were $6.0\~9.8\times10^6,\;5.3\~9.0\times10^6,\;5.4\~8.5\times10^6\;CFU/g$, respectively. During the fermentation of dough, viable cells of TBC, yeasts and LAB increased $0.3\~0.4$ log cycle and pH was decreased whereas acidity increased as the progress of fermentation. Total viable cells in Jeungpyun before storage were $5.0\times10^1\;CFU/g$. During storage of Jeungpyun, TBC, yeasts and LAB of control group increased 2.6, 2.4, 2.1 log cycle at $5^{\circ}C$ and 4.8, 4.6, 4.5 log cycle at $50^{\circ}C$, respectively, when reached at maximum level. Major microflora of Jeungpyun was composed of yeasts and LAB during fermentation of dough and storage at $5^{\circ}C\;and\;20^{\circ}C$. Addition of PJM, inhibited the growth of microorganisms, the changes of PH and titrable acidity of Jeungpyun during storage at both of $5^{\circ}C\;and\;20^{\circ}C$. From these results, the addition of PJM extended the shelf-life of Jeungpyun during storage at $5^{\circ}C\;and\;20^{\circ}C$.

• Nutrition Research and Practice
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• 제9권3호
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• pp.249-255
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• 2015

BACKGROUD/OBJECTIVES: This study was conducted in order to investigate the effect of peanut sprout extracts (PSE) on health indices in overweight and obese women (BMI $${\geq_-}23kg/m^2$$). SUBJECTS/METHODS: Subjects were divided into three groups by double-blind randomized trial; the Placebo group (n = 15) and the Low PSE group (2.6 g PSE/day, n = 15), and the High PSE group (5.8 g PSE/day, n = 15). Subjects consumed 12 capsules per day, three times a day, 30 min before meals, for 4 weeks. Anthropometric data, blood biochemical variables, and dietary intake were evaluated before and after the experiments. RESULTS: In the Low and High PSE group, the waist circumference showed a significant decrease between pre- and post-test. In the Low PSE group, the reduction of systolic blood pressure between pre- and post-test was statistically significant. Serum LDL or triglyceride levels in both Low and High PSE groups were significantly decreased, and serum alanine transaminase and aspartate transaminase were significantly decreased only in the Low PSE group. The parameters regarding erythrocyte and leucocyte counts showed no significant differences between pre- and post-test among groups, which suggested the safety of intake of peanut sprouts as a dietary supplement. CONCLUSIONS: This study indicates that PSE supplementation improves abdominal obesity and overall health indices. Therefore, an appropriate amount of peanut sprouts may be a plausible effective agent for obesity and obesity related health problems in obese women.

• 수산해양교육연구
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• 제22권4호
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• pp.529-536
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• 2010

This study was conducted to effect of extruded pellets (EPs) and moist pellet (MP) diet on growth and fish health parameters in farm cultured olive flounder Paralichthys olivaceus. Two replicate groups of 2,600 fish per each tank (initial weight of $30.1{\pm}0.2$ g) were fed one of the three EPs (EP1, EP2 and CEP) and one MP for 13 months. In field feeding experiment conducted in commercial flounder farm, survival, growth (30-600 g) and condition factor of fish fed experimental EP1 and EP2 were comparable to those of fish fed MP, but considerably higher feed efficiency and protein efficiency ratio were observed in fish fed experimental EPs. Viable cell counts from diet and water from MP diet were considerably higher than those from EP diet, and lysozyme activity from EP diet was higher than that from MP diet. GOT and GPT of fish fed the EP diet were considerably lower than those from MP group, but total protein and glucose concentration of fish fed the EP groups were not significantly different from that of fish fed the MP. Therefore, these results strongly suggest that EP diets could be developed to replace MP diet without adverse effects on growth performance and to enhance the immunity and protective ability of olive flounder against fish disease such as Vibro, Edwardsiella and Strptococcus.

• 한국식품과학회지
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• 제33권2호
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• pp.252-255
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• 2001

뽕잎 분말이 1, 10%가 되도록 사료에 첨가시켜 4주동안 SD 흰쥐에게 급여한 후 이들의 대장 내용물로부터 총균수와 주요장내미생물의 생균수를 배지를 이용하여 혐기배양한 후 측정한 결과 총균수는 뽕잎 투여군에서 대조군에 비해 감소하는 경향을 보였다. 그리고 유해균으로 분류할 수 있는 Clostridium은 대조군보다 뽕잎투여군에서 유의성있게 감소하였고, E. coli와 Staphylococcus도 감소하는 경향을 보였다. 뽕잎 메탄올 추출물과 분획물들의 미생물의 생장억제효과를 측정한 결과, 헥산분획과 물분획물이 Clostridium perfringens에 대하여 억제효과를 보였다. 장내균총의 개선 측면에서 뽕잎은 기능성 식품소재로서의 이용가능성이 있는 것으로 나타났다.

• International Journal of Oral Biology
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• 제39권2호
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• pp.57-63
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• 2014

The purpose of this study is to evaluate salivary flow rate, salivary pH, and cariogenic activity using unstimulated saliva of the head and neck cancer patients. Twenty three cancer patients (19 males, 4 females) who had undergone chemotherapy and radiation therapy and twenty four healthy volunteers (14 males, 10 females) as a control were included. Salivary flow rate, salivary pH, and cariogenic activity using unstimulated saliva were examined. Compared to saliva of the control group, salivary flow rate (p<0.001) and salivary pH (p<0.001) were significantly lower in head and neck cancer patients. The colony counts of Lactobacilli was higher in head and neck cancer patients (p<0.05) than in control group. These salivary factors and cariogenic activity can increase the prevalence of dental caries in head and neck cancer patients.