• Transactions of Materials Processing
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• v.16 no.5 s.95
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• pp.364-369
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• 2007

The effect of temperature on the forming limit diagram was investigated for AZ31B magnesium alloy sheet through the limit dome height test in the range from room temperature to $300^{\circ}C$. The formability of AZ31B sheet was improved significantly according to the increasing temperature. Also we studied the springback characteristics through the 2D draw bending test with different blank holding forces at elevated temperatures. Springback quantity was considerably reduced as temperature went up. The blank holding force in the range used, however, had little influence on springback. Experimental results obtained in this study may provide a material database for AZ31B sheet.

• Journal of Animal Environmental Science
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• v.13 no.1
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• pp.35-44
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• 2007

The effects of microbial feedstuff additives on feed conversion rate and physical and chemical characteristics of excreta in growing pigs were investigated. Three different products (A, B and C) were compared. Microbial population tests showed B contained higher numbers of total bacteria, Lactobacillus spp. and yeasts. The amylase activity of B was also higher than that of A and C. The daily feed intake rates fer control, A, B and C were 2.06, 2.13, 2.17 and 2.34 kg, respectively. Pigs feed product C had the highest liveweight gain(2.89 kg). However, the results of feed conversion rate were not significantly different between treatments. Amount of faces excreted for control, A, B and C was 1.18, 1,19, 1.23 and 1.32 kg, respectively. Urine volume for control, A, B, and C was 1.91, 1.80, 2.19 and 2.31 kg respectively. Moisture content, T-N, $P_2O_5$ and $K_2O$ in pig manure were not significantly different between treatments. The range of BOD values was 63,453 to $73,758mg/\ell$ for faeces, and 5,678 to $7,428mg/\ell$, for urine. SS values of solid and liquid excreta ranged from 142,200 to 176,000 and from 710 to $1,025mg/\ell$, respectively.

• Korean Journal of Poultry Science
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• v.39 no.2
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• pp.133-141
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• 2012

This study was carried out to investigate the performance of laying period of two-way crossbred of Korean native chickens. A total of four hundred eighty female 2-crossbred chicks that restored strains and were aboriginal at National Institute of Animal Science. Treatments were four crossbreds (4 replications/crossbred, 30 birds/replication) as A) C strain ${\times}$ S strain, B) C strain ${\times}$ H strain, C) R strain ${\times}$ S strain, and D) L strain ${\times}$ H strain, respectively. There were no significant difference on age, egg weight, and body weight at first egg among crossbreds (P>0.05). Body weight of D crossbred was lower compared to other crossbreds at the age of 24, 32, 40 and 60 week (P<0.05). Feed intake of A crossbred was highest among crossbreds (P<0.05). Weekly egg weight of A crossbred was the highest among crossbreds all laying period except 48~52 and 60~64 weeks. Hen-house egg production of A and B crossbreds was higher than that of C and D crossbreds (P<0.05). Hen-day egg production decreased after at the age of 36 weeks. Weekly egg production of A and B crossbreds was higher compared to C and D crossbreds (P<0.05). These results suggested the basic data on the record of laying period of 2-crossbreed Korean Native Chickens.

• Journal of electromagnetic engineering and science
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• v.16 no.3
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• pp.164-168
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• 2016

A dual-band through-the-wall imaging radar receiver for a frequency-modulated continuous-wave radar system was designed and fabricated. The operating frequency bands of the receiver are S-band (2-4 GHz) and X-band (8-12 GHz). If the target is behind a wall, wall-reflected waves are rejected by a reconfigurable $G_m-C$ high-pass filter. The filter is designed using a high-order admittance synthesis method, and consists of transconductor circuits and capacitors. The cutoff frequency of the filter can be tuned by changing the reference current. The receiver system is fabricated on a printed circuit board using commercial devices. Measurements show 44.3 dB gain and 3.7 dB noise figure for the S-band input, and 58 dB gain and 3.02 dB noise figure for the X-band input. The cutoff frequency of the filter can be tuned from 0.7 MHz to 2.4 MHz.

• Journal of the Korean Applied Science and Technology
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• v.1 no.1
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• pp.37-47
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• 1984

Effects of garlic on hypocholesterolemia, anticoagulation and hypoglycemia were studied in the present experiments using male rats. The results were summarized as follows. 1. The supplementation of $2{\sim}4%$ garlic to 2% cholesterol diets did not affect food intake and weight gain in male rats. 2. Rat's groups fed the diets supplemented with $2{\sim}3%$ garlic (C.D.E.F) to 2% cholesterol diet (B) decreased serum total cholesterol levels by $16{\sim}32%$, triglyceride levels by $18.6{\sim}26.8%$ and ${\beta}/{\alpha}-lipoportein$ rations by $42{\sim}58%$, but increased HDL-cholesterol levels by $29{\sim}65%$ as compared to B group, and so the author assumes that garlic supplementation exerts hypocholesterolemic effect on cholesterol - fed rats because of the increase of HDL and HDL - cholesterol levels. 3. Rat's groups fed the diets supplemented with $2{\sim}4%$ garlic (C.D.E.F) to 2% cholesterol plus 0.25% bile salt diet (B) increased whole blood coagulation times, prothrombin times and fibrinolytic activities, but decreased plasma fibrinogen levels as compared to B group, and so the author assumes that garlic supplementation exerts anticoagulative effect because of the inhibition of fibrinogen synthesis in male rat's liver. 4. Rat's groups fed the diets supplemented with $2{\sim}4%$ garlic (B.C.D.E) to standard diet (A) decreased serum glucose levels by $1{\sim}24%$, but increased serum insulin concentrations by $0.5{\sim}3.0$ times as compared to A group, and so the author assumes that garlic supplementation exerts hypoglycemic effect because of the increase of serum insulin levels by stimulation pancreatic secretion of insulin from ${\beta}-cells$ in the islets of Langerhans.

• Journal of Food Hygiene and Safety
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• v.30 no.3
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• pp.242-248
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• 2015

This study was performed to investigate the microbiological contamination on toothbrushes, toothbrush caps, and tooth cleaning cups in the child care centers and to evaluate the toxin genes, toxin production ability and antibiotic resistance of food-borne pathogens. The average number of total aerobic bacteria and fungi were 5.3 log CFU and 3.2 log CFU. Coliform bacteria were detected in 41 (54.7%) of 75 toothbrushes, 13 (44.8%) of 29 toothbrush caps, and 29 (44.6%) of 65 tooth cleaning cups. Salmonella spp. was not detected in all of samples but Bacillus cereus was isolated from 1 (1.3%) of 75 toothbrushes and 2 (3.1%) of 65 tooth cleaning cups. Staphylococcus aureus was detected in 1 (1.5%) of 65 tooth cleaning cups. The nheA, nheB, nheC, hblC, hblD, hblA and entFM toxin genes were possessed in B. cereus isolated from toothbrush which also produce NHE and HBL enterotoxins. S. aureus was resistant to ampicillin and penicillin, while B. cereus was resistant to ${\beta}-lactam$ antibiotics. These results indicated that the sanitary conditions of toothbrushes and tooth cleaning cups in the child care centers should be improved promptly. The UV sterilization after drying and then storage in dried condition is required to improve the sanitary condition of toothbrushes and tooth cleaning cups in the child care center.

• Korean Journal of Agricultural Science
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• v.22 no.2
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• pp.170-179
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• 1995

This study was conducted to investigate the genetic constitution of blood proteins and enzymes in 238 Korean Native cattle reared at Korean Native Cattle Breeding Center, National Livestock Cooperative Federation. The genetic polymorphisms of post-transferrin-2(pTf-2), transferrin(Tf), post-albumin(pAlb), albumin(Alb), ceruloplamin(Cp), amylase-I(Am-I) and hemoglobin(Hb) were analyzed by using PAGE(polyacrylamide gel electrophoresis) and STAGE(starch gel electrophoresis). The genotypes and gene frequencies were estimated at these loci for each blood proteins and enzymes. The results obtained from this study were summarized as follows : 1. The pTf-2 locus were identified to be genetically controlled by codominant alleles designated pTf-2 F and S, and the distribution of genotypes were 46.22, 46.64 and 7.14% for pTf-2 FF, FS and SS types, and the gene frequencies of the pTf-2 F and S allele were 0,695 and 0.305, respectiveley. 2. The Tf locus were found to be controlled by Tf A, D1, D2 and E alleles, and the distributioin of genotypes were 0.84, 13.87, 13.03, 10.92, 22.27, 12.61, 2.94, 15.51, 6.72 and 1.68% for Tf AA, AD1, AD2, AE, D1D1, D1D2, D1E, D2E and EE types, and the gene frequencies of Tf A, D1, D2 and E were 0.197, 0.430, 0.191 and 0.081, respectively. 3. The pAlb locus were observed to be controlled by two alleles, pAlb F and S, and the distribution of genotypes were 42.86, 33.19 and 23.95% for pAlb FF, FS and SS types, and the gene frequencies were 0.595 and 0.405 for Tf F and S allele, respectively. Also the gene frequencies of Alb was 1.000 of Alb A allele. 4. The Cp locus were identified to be controlled by Cp F and S allele, and the distribution of genotypes were 23.11, 34.87 and 42.02% for Cp FF, FS and SS types, and the gene frequencies were 0.405 and 0.595 for Cp F and S allele, respectively. 5. The Am-I locus were observed to be genetically controlled by Am-I B and C allele, and the distribution of genotypes were 51.26, 16.81 and 31.92% for Am-I BB, BC and CC types, and the gene frequencies of Am-I B and C alleles were 0.597 and 0.403, respectively. 6. The Hb locus were found to be controlled by Hb A and B alleles, and the distribution of genotypes were 93.19, 16.39 and 0.42% for Hb AA, AB and BB types, and the gene frequencies of Hb A and B alleles were 0.914 and 0.086, respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.446-450
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• 2001

In this study, microstructural and electrical properties of (Pb)(La,Nd)$TiO_3$ cerramics were investigated as a function of CuO addition. Taking into consideration Tc of $325^{\circ}C$, dynamic range of 49dB( at the wafer form) and density of $7.71g/cm^{3}$, it can be concluded that the specimen S2 sintered at $1200^{\circ}C$ is the best for the resonator application, Dynamic characteristics of energy-trapped 20MHz SMD type resonator as a function of internal dot size variation were also investigated. Dynamic range characteristics showed the highest value of 60.72dB at S2-4(dot size 1.13mm).

• Natural Product Sciences
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• v.2 no.1
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• pp.9-13
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• 1996

Three new withanolides, designated as withatatulins B, C, and D, were isolated from the fresh flowers of Datura tatula Linn. Detailed spectral analysis of these compounds permitted advancement of their structures respectively, as $5{\beta},6{\beta}-epoxy-12{\beta}$,21-dihydroxy-1-oxo-witha-2,24-dienolide (2), $6{\beta},12{\beta},21-trihydroxy-1-oxowitha$ 2, 4,24-trienolide (3) and $5{\beta},6{\beta},12{\beta}$,21-tetrahydroxy-1-oxo-witha-2,24-dienolide (4a). Withanolides with oxygen functions both at 12 and 21-positions are rare and first reported from Datura species.

• Korean Journal of Food Science and Technology
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• v.10 no.2
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• pp.181-188
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• 1978

To study on the changes in saponins from callus mass by tissue culture, the callus was derived from the petiole of Korean Ginseng (Panax Ginseng C.A. Meyer) and cultivated on Murashige and Skoog's agar medium supplemented with 2.4-dichlorophenoxyacetic acid and kinetin for 8 months. Then, well-grown callus was analyzed for its components estimation. The results obtained are as follows: (1) When saponins isolated from callus mass were chromatographed on a silca gel plate, and determined by the thinchrograph TFG-10, the ratio of Rb, c to Rg(f) in saponins was 2.16 to 1 and Rb, c, d to Re, g (f) was 1 to 1.63, while in the case of saponins from the root of Panax Ginseng grown by soil culture, the ratio of Rb, c to Rg(f) was 1.03 to 1 and the ratio of Rb, c,d to Re, g(f) was 1 to 1.17. (2) Sapogenins were obtained from the hydrolysates of saponins, and determined by thinchrograph TFG-10. The ratio of panaxadiol to panaxatriol in sapogenins from callus saponins was 2.66 to 1, while the ratio of panaxadiol to panaxatriol in sapogenins from ginseng root saponins was 1.86 to 1. From the results above mentioned, we concluded that the relative contents of sapogenins in saponins from callus mass by tissue culture were different from those in saponins from ginseng root by soil culture.