• Journal of Advanced Marine Engineering and Technology
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• v.17 no.4
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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.

• The Korean Journal of Mycology
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• v.40 no.4
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• pp.210-214
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• 2012

The aim of this study was to determine changes of physicochemical properties and microorganisms of commercial Makgeolli during storage at $10^{\circ}C$ and $25^{\circ}C$ During storage at $10^{\circ}C$ for 11 days, ethanol contents did not increased up to 7.0%, and pH and total acidity were ranged with 3.12-3.99 and 0.22-0.28%, respectively. Makgeolli which was storaged at $25^{\circ}C$ for 11 days showed more than 7.0% of alcohol contents, pH of 3.96-4.17 and total acidity of 0.27-0.30%. Yeast cell counts showed maximal $2.90-16.00{\times}10^7$ CFU/mL at $10^{\circ}C$ for 3 days and $1.12-29.40{\times}10^7$ CFU/mL at $25^{\circ}C$ for 1 day. Lactic acid bacteria and total bacteria cell counts of Makgeolli which was storaged at $25^{\circ}C$ for 11 days were higher than those $10^{\circ}C$ storage. In preference test, Makgeolli from storage at $10^{\circ}C$ for 11 days was showed the level of 4.9-5.2 points however, Makgeolli from storage at $25^{\circ}C$ for one day showed below 5.0 point.

• Journal of Food Hygiene and Safety
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• v.25 no.1
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• pp.73-78
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• 2010

This research was conducted to assess applicability of photostimulated luminescence (PSL) and Thermoluminescence (TL) methods for investigation of infant and young children products, nut, seasoned dried fish, spice, dried fruits, fruit & vegetable, grain and marine products, which are not approved for irradiation in Korea. PSL results show that the photon counts of non-irradiated samples were lower than 700, while those of irradiated samples were higher than 700. In TL measurement, TL ratio of irradiated samples were higher than 0.1 or ones can decrease below 0.1 whereas the temperature range of TL Glow curve was between $150{\sim}250^{\circ}C$. Monitoring result about 8 class of 325 not approved to irradiated foods, photon counts of samples were less than 700, and after re-irradiation TL Ratio ($TL_1/TL_2$) through re-irradiation step at 1 kGy were higher than 0.1 for the all samples. Therefore, these results suggested that PSL and TL measurements were useful detection methods for 8 class food products not approved to irradiation in Korea and all sample (325 cases) were not irradiated when we analysed by PSL and TL methods.

• Food Science and Preservation
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• v.20 no.1
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• pp.30-36
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• 2013

Red-ripe 'Betatiny' jujube-shaped cherry tomato fruits via stem maintenance or stem removal were stored at $20^{\circ}C$ for 12 days. Their quality and microbial safety parameters like their respiration rate, weight loss, soluble solids content (SSC), titratable acidity (TA), firmness, hue value, aerobic microflora, coliform, yeast and mold count, and decay were evaluated during their storage. The jujube-shaped cherry tomato fruits whose stems were removed lost less weight than the fruits whose stems were maintained during their 12 days of storage. The stem removal lowered the respiration more significantly than the stem maintenance, and the formation of novel tissues at the stem scar that resulted from the stem removal was observed morphologically. The SSC, TA and hue value of the skin color decreased after eight storage days, but showed no difference between the stem maintenance and removal. The stem had higher microbial counts like aerobic microflora, coliform, and yeast and mold counts. The stem maintenance showed a short shelf-life because molds grew on the attached stem after five storage days. The shelf-life of the jujube-shaped cherry tomato fruits whose stems were removed was about eight days, but that of the fruits whose stems were maintained and that were stored at $20^{\circ}C$ was only about six days.

• Natural Product Sciences
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• v.20 no.1
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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.

• Korean journal of food and cookery science
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• v.20 no.6 s.84
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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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• v.9 no.3
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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.

• Journal of Fisheries and Marine Sciences Education
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• v.22 no.4
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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.

• Korean Journal of Food Science and Technology
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• v.33 no.2
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• pp.252-255
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• 2001

This study was performed to investigate the influence of dietary mulberry leaf on the intestinal microflora in rats. Rats were fed each experimental diets containing 1%, 10% of mulberry leaf powder for 4 weeks. Total viable counts and the numbers of Bifidobacterium, Lactobacillus, Clostridium, E. coli and Staphylococcus were determined by nonselective media and various selective media. A decrease in the intestinal population of Clostridium was shown in dietary mulberry leaf group. The E. coli and Staphylococcus populations decreased in dietary mulberry leaf group compared with control group. Methanol extract and fractions of mulberry leaf were subjected to an in vitro screening test for their growth-inhibitory activity. Methanol extract and Water fraction of Mulberry leaves showed weak growth-inhibition of Clostridium perfringens. These results indicate that the composition of gastrointestinal microflora was improved by treatment of mulberry leaves in SD rats and was very effective for growth inhibition of the intestinal harmful bacteria in intestine. Therefore, the mulberry leaves as a newly bio-material can be a useful material for physiologically functional food.

• International Journal of Oral Biology
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• v.39 no.2
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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.