• Aerospace Industry
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• s.92
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• pp.24-27
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• 2006

참여정부의 국방획득 제도개선 추진의 결과로 방위사업법이 제정되고, 이 법에 따라 방위사업청 산하 정부출연 법인체로 '06년 2월 2일 새로운 조직의 국방기술품질원(이하 기품원)이 탄생하게 되었다. 이에 기품원 사천센터에서 있었던 T-50엔진(F-404-102)의 내구성 시험평가 현황을 알아보고 이 과정에서 느낀 교훈을 살펴보고자 한다.

• Proceedings of the KWS Conference
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• 1996.05a
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• pp.176-178
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• 1996

• Journal of the East Asian Society of Dietary Life
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• v.18 no.5
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• pp.789-796
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• 2008

This study was carried out to investigate the effect of the addition of red wine on the color, water activity, hardness, pH, 2-thiobarbituric acid (TBARS) value, volatile basic nitrogen (VBN) content and total plate count of beef jerky during storage at room temperature for 4 weeks. Beef jerky was prepared using three variations: beef jerky containing 50 mL water (T0), beef jerky containing a combination of 25 mL water and 25 mL red wine (T1) and beef jerky containing 50 mL red wine (T2). The lightness ($L^*$) was the lowest at the 4-week storage period, and the $L^*$ value of T1 and T2 were lower than that of T0 (p<0.05). The redness ($a^*$) tended to decrease during storage, with the $a^*$ value of T1 and T2 being higher than that of the T0 (p<0.05). The yellowness ($b^*$) during storage was not changed, and the $b^*$ value was not significantly different among the different samples tested. The water activity decreased during storage and T0, T1 and T2 was 0.57, 0.57 and 0.60 after 4 weeks of storage, respectively(p<0.05). The hardness increased during storage and the hardness of T2 stored for 4 weeks was lower than that of T0 and T1 (p<0.05). The pH was decreased with an increase in storage time (p<0.05). The TBARS value increased during storage and the TBARS value of T1 and T2 stored for 4 weeks was lower than that of T0 (p<0.05). The VBN content increased during storage and T2 stored for 4 weeks showed the lowest (p<0.05). The total plate count tended to increase during storage, and T0 stored for 4 weeks showed the highest (p<0.05).

• Journal of Environmental Health Sciences
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• v.21 no.2
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• pp.27-35
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• 1995

In order to investigate acute toxicity and bioconcentration of heavy metals for a freshwater fish, the fish used in this experiment was goldfish, Carassius auratus. Each ten goldfish was accommonidated in a water and was treated with different concentration of Pb and Cu compound. The 24 $hr-LC_{50}$ was obtained by plotting on the log-normal distribution graph. Furthermore, the combined effect of Pb and Cu was also investigated the fish was treated with Pb or Cu compound only, and Pb and Cu compound together, respectively. These results were summarized as follows: 1. The 24 $hr-LC_{50}'s$ of Pb and Cu were 7.48 mg/l and 0.666 mg/l, respectively. 2. When single or/and combined treatment with Pb(7.0 mg/l) or/and Cu(0.6 mg/l) to Carassius auratus for 24 hours were performed, there was significant difference between the single or/and the combined treatment in their bioaccumulated Cu concentrations. Cu concentrations in goldfish were higher in the combined treatment than in the single treatment. 3. When Carassius auratus was exposed to 0.748 mg/l (1/10 of 24 $hr-LC_{50}$) and 1.496 mg/l of Pb (1/5 of 24 $hr-LC_{50}$) for 7 days, the bioconcentration factors (BCF) were 79.14 and 100.11 for Pb, respectively. The BCF of Pb was obtained as a linearity according to the concentration and exposure time as follows log BCF=1.014 log $P\cdot T$+1.011 ($r^2$=0.9041) where, P: pollutant concentration(mg/l) T: exposure time(day) 4. When Carassius auratus was pxposed to 0.0666 mg/l (1/10 of 24 $hr-LC_{50}$) and 0.1332 mg/l of Cu (1/5 of 24 $hr-LC_{50}$) for 7 days, the bioconcentration factors (BCF) were 55.42 and 63.24 for Cu respectively. The BCF of Cu was obtained as a linearity according to the concentration and exposure time as follows log BCF=0.571 log $P\cdot T$+1.823 ($r^2$=0.8974) where, P: polutant concentration(mg/l) T: exposure time(day)

• Parasites, Hosts and Diseases
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• v.50 no.2
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• pp.161-164
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• 2012

To evaluate the efficacy of ronidazole for treatment of Tritrichomonas foetus infection, 6 Tritrichomonas-free kittens were experimentally infected with a Korean isolate of T. foetus. The experimental infection was confirmed by direct microscopy, culture, and single-tube nested PCR, and all cats demonstrated trophozoites of T. foetus by day 20 post-infection in the feces. From day 30 after the experimentally induced infection, 3 cats were treated with ronidazole (50 mg/kg twice a day for 14 days) and 3 other cats received placebo. Feces from each cat were tested for the presence of T. foetus by direct smear and culture of rectal swab samples using modified Diamond's medium once a week for 4 weeks. To confirm the culture results, the presence of T. foetus rRNA gene was determined by single-tube nested PCR assay. All 3 cats in the treatment group receiving ronidazole showed negative results for T. foetus infection during 2 weeks of treatment and 4 weeks follow-up by all detection methods used in this study. In contrast, rectal swab samples from cats in the control group were positive for T. foetus continuously throughout the study. The present study indicates that ronidazole is also effective to treat cats infected experimentally with a Korean isolate of T. foetus at a dose of 50 mg/kg twice a day for 14 days.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.4
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• pp.474-477
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• 2000

Two experiments were conducted to study the use of urea-treated rice straw (UTRS) and whole sugar cane (WSC) crop as roughage sources for dairy cattle during the dry season. Experiment I, four rumen-fistulated dairy crossbred steers were assigned to receive roughage treatments according to a $4{\times}4$ Latin square design: $T_1=urea-treated$ (5%) rice straw, $T_2=UTRS$ and WSC at 75:25% DM, $T_3=UTRS$ and WSC at 25:75% DM, and $T_4=WSC$. Experiment II, three rumen fistulated, late lactating multiparous Holstein-Friesian crossbreds were randomly allotted to a $3{\times}3$ Latin square design to receive three types of roughages; $T_1=WSC$, $T_2=UTRS$, $T_3=WSC+UTRS$ at 50:50% DM. It was found that combination of UTRS and WSC at 75:25 ratio significantly increased DM intake while intake of WSC alone was lowest. Moreover, inclusion of UTRS into WSC enhanced digestibilites (Exp. I). In Exp. II, combination of UTRS with WSC at 50:50 ratio (DM) enhanced DM intake (kg/d) (p<0.05) and especially milk yield, milk fat and protein percentages. The findings suggest the combined use of WSC and UTRS improved the feeding values of these roughages for dairy cattle during the dry season.

• Journal of the Korean Magnetics Society
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• v.27 no.3
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• pp.77-81
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• 2017

The rotatable anisotropy effect was observed in the ferromagnetic resonance measurement in exchange coupled ferromagnetic/antiferromagnetic thin films and it was due to rotation of antiferromagnetic layer by the exchange coupling energy. We analyzed the CoFe thickness dependence of rotatable anisotropy field and ferromagnetic resonance linewidth in exchange coupled $CoFe(t_F)/MnIr(2.5nm)$ thin films. The rotatable anisotropy field was inversely propositional to the CoFe thickness and it was well fitted by the rotatable anisotropy energy of $0.96erg/cm^2$. The ferromagnetic resonance linewidth were linearly propositional to the rotatable anisotropy field in $t_F$ < 50 nm, while it was more dominated by the eddy current effect in $t_F$ > 50 nm.

• Journal of Environmental Impact Assessment
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• v.22 no.4
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• pp.319-327
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• 2013

This study was conducted to identify runoff characteristics of pollutants using flow duration curve(FDC) and load duration curve(LDC) in Youngbon A watershed during 2009~2011. A flow rate and pollutant load in the study watershed were estimated by equation of stage-discharge and discharge-loads rating curve. From these methods, BOD, T-N, and T-P have evaluated whether water quality standards would have attained. Results showed that BOD loads of about 50% plotted above the LDC, while T-N and T-P loads of about 50% plotted below the curve. It means that BOD of about 50% have exceeded the water quality criteria, while T-N and T-P of about 50% have complied with the water quality standards. Meanwhile, BOD, TN and T-P loads plotted above the LDC of low flows, implying that they were more affected by point pollution sources than nonpoint pollution sources in the study watershed.

• Korean Journal of Microbiology
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• v.44 no.1
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• pp.37-42
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• 2008

Optimal conditions for the biodegradation of endocrine-disrupting bisphenol A (BPA) were examined for the white rot fungus Trametes versicolor isolated in Korea. T. versicolor degraded 100% of 50 mg/L bisphenol A during 12 hr in yeast extract-malt extract-glucose (YMG) medium. When BPA was added to the 5-day preincubated fungal culture in YMG medium, all BPA was removed in 2 hr. T. versicolor could efficiently degrade BPA at $35^{\circ}C$, pH 6 in YMG medium. T. versicolor could more easily remove BPA of $1{\sim}25\;mg/L$ than that of higher concentrations ($50{\sim}100\;mg/L$) in YMG medium. T. versicolor degraded 100% of 50 mg/L BPA for 36 h in a minimal medium, which is lower degradation rate than that in YMG medium. Optimal conditions for BPA biodegradation in the minimal medium were similar to those in YMG medium. When BPA (50 mg/L) was added into domestic wastewater, it could be completely removed by T. versicolor. During the biodegradation of BPA by T. versicolor in YMG medium, its estrogenic activity decreased.

• Journal of agriculture & life science
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• v.43 no.5
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• pp.9-15
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• 2009

The purpose of this study was to find out the optimum SMP carriers in seeds of 12 pepper cultivars to alternate Micro-eel E. It showed that calcium carbonate caused the lower germination rates in proportion of water volumes and the radicle protrusion during priming period. Micro-cel E induced also the radical protrusion, even though it shortened $T_{50}$ in Wang cultivar, in proportion of water volumes. Diatomaceous earth shortened both $T_{50}$ and Mean days germination(MDG) in Choyang and Hyangchon cultivars, although it caused the radicle protrusion in treatment of $1.5{\times}$ water proportion. In Wang cultivar, Diatomaceous earth shortened $T_{50}$ by 0.60 and 0.05 days at 1.0 and $1.5{\times}$ water proportions respectively compared to the Micro-cel E at 5.0 and $7.0{\times}$ water proportions. Therefore, it could be suggested that Diatomaceous earth for the carrier might be suitable in pepper cultivars to alternate Micro-cel E, and $1.0{\times}$ water proportion should be available for processing.