• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.11
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• pp.2573-2584
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• 1997

In this paper, Ca, Sn substitute YIC(Yttrium Iron Garnet) ceramics were fabricated with Al substitutions in Fe sites. The strip-line circulator was designed and the properties of fabricated ciculator were measured. When the electric, magnetic and microwave properties were measured in Ca, Sn substituted YIG with Al subsititions, the relative permittivity and perfmeability in microwave frequencies were 15.623 and 0.972, repectively. For $Y_{2.4}Ca_{0.3}Sn_{0.3}Fe_{5-x}Al_xO_{12}$ garnet ceramics sintered at $1450^{\circ}C$, the ferrimagnetic resonance line width $\Delta{H}$) of 42 Oe and the saturation magnetization of 487 G were measured at 10 GHz. The strip-line circulator was simulated with 3-D FEM(Finite Element Method) software and designed to have insertion loss of 0.8dB, return loss of 25dB, isolation of 35dB at the center frequency of 1.9GHz. The fabricated strition loss of 0.8B, reture loss of 25dB, isolation of 35dB at the center frequency of 1.9GHz. The fabricated strip-line junction circulator using above YIG ceramics had insertion loss of 0.869dB, return loss of 26.955dB, isolation of 44.409dB at the center frequency of 1.9GHz.

• Fisheries and Aquatic Sciences
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• v.17 no.3
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• pp.361-367
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• 2014

Cuttlefish Sepia esculenta are commercially important in Korea. Assessments of their biomass currently depend on fishery-landings data, which may be biased. Towards fishery-independent acoustic surveys of cuttlefish, target strength (TS) measurements at 70 and 120 kHz were made of 23 live cuttlefish, in early May 2010. The fish were caught by traps in the inshore waters around Geojedo, Korea. The TS were measured using split-beam echosounders (Simrad ES60 and EY500, respectively). The cuttlefish mantle lengths (L) ranged from 15.6 to 23.5 cm (mean L=17.8 cm) and their masses (W) ranged from 335 to 1020 g (mean W=556.1 g). Their mean TS values at 70 and 120 kHz were -33.01 dB (std=1.39 dB) and -31.76 dB (std=2.15 dB), respectively. The mean TS at 70 kHz was 0.17 dB higher than the TS-length relationship resulting from a least-squares fit to the data ($TS=24.67{\log}_{10}L(cm)-64.03$, $r^2$ = 0.52, N=23). The mean TS at 120 kHz was 0.45 dB higher than the fitted TS-length relationship ($TS=40.59{\log}_{10}L(cm)-82.96$, $r^2$ = 0.58, N=23). The differences between the mean TS values and an equation regressed from all of the TS measurements at both frequencies ($TS=24.92{\log}_{10}L(cm)-4.92{\log}_{10}{\lambda}(m)-22.82$, $r^2$ = 0.86, N=46) was 0.22 dB at 70 kHz and 0.31 dB at 120 kHz, respectively.

• Food Science of Animal Resources
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• v.30 no.6
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• pp.946-950
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• 2010

This study evaluated the antimicrobial effects of meat processing-related organic acids on Burkholderia thailandensis (Burkholderia pseudomallei surrogate) with different water activities. B. thailandensis KACC12027 (4 log CFU/mL) was inoculated in microwell plates containing tryptic soy broth pH-adjusted to 4, 5, 6, and 7 with ascorbic acid, citric acid, and lactic acid and with water activities adjusted to 0.94, 0.96, 0.98, and 1.0 with NaCl, followed by incubation at $35^{\circ}C$ for 30 h. The optical density (OD) of the samples was measured at 0, 3, 6, 12, 24, and 30 h at 595 nm to estimate the growth of B. thailandensis. Growth of B. thailandensis was observed only at water activity of 1.0. In general, more bacterial growth (p<0.05) was observed at pH 6 than at pH 7, and the antimicrobial effects of the organic acids on B. thailandensis were in the following order: Ascorbic acid > lactic acid > citric acid after incubation at $35^{\circ}C$ for 30 h. These results indicate that organic acids in meat processing-related formulations should be useful in decreasing the risk related to an emerging high risk agent (B. pseudomallei).

• Korean Journal of Poultry Science
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• v.27 no.1
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• pp.51-61
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• 2000

This study was conducted to estimate the general production performance, heritabilities, and genetic phenotypic correlations on several economic traits by multiple trait animal model in Korean native chicken. The data were collected from the records of 5,192 pullets produced from 2,029 dams and 250 sires in Daejon Branch, National Livestock Research Institute from April 10. 1994 to February 10. 1997. Body weights of Red Brown (RB), Yellow Brown (YB), Grey Brown (GB) and Black (B) strains were 1,649.9, 1,439.6, 1,455.6 and 1,575.3g at age of 150 days and 1,923.5, 1,689.6, 1,812.4 and 1,924.0g at age of 270 days, respectively. The ranges of coefficient of variation for body weight were 11.52 to 14.02 at age of 150 days and 12.82 to 14.59% at age of 270 days, respectively. The first eggs of RB, YB, GB and B strains were produced at 147.4, 146.5, 151.1 and 152.1 days, respectively and the coefficients of variation were 7.80 to 8.41%. Egg weight at 270 days were 49.7, 47.6, 48.8 and 48.7 g for RB, YB, GB nd B strains, and coefficients of variation were 6.99 to 7.94% . The number of eggs at age of 270days were 75.8, 78.0, 76.7 and 68.8 for RB, YB, GB and B strains, respectively, and coefficient of variations were 23.87 to 29.89%. On heritability estimates in RB, YB, GB and strains body weight were 0.40, 0.10, 0.09 and 0.57 for RB, YB, GB and B strains at age of 150 days, and 0.23, 0.09, 0.38 and 0.24 at age of 270 days were 0.39, 0.47, 0.60 and 0.62, and egg weights at 270 days and age at 1st egg were 0.36, 0.12, 0.38 and 0.26, number of egg production at 270 days were 0.44, 0.36, 0.58 and 0.49, respectively. The genetic correlation coefficients of body weight with the age of first egg, egg weight and number of egg production at 270days were -0.07∼0.67, -0.24∼0.70 and 0.12∼0.41, respectively ; age of first egg with number of egg production at 270days and egg weight were -0.75∼0.91 and 0.34∼0.97 ; and egg weight with number of egg production at 270days were 0.18∼0.68. The phenotypic correlation coefficients of body weight with at age of first egg, egg weight and number of egg production at 270days were -0.01∼0.74, -0.04∼0.72 and 0.25∼0.57 ; age of first egg with number of egg production at 270days and egg weight were 0.26∼0.52 and 0.52∼0.92, respectively ; and egg weight with number of egg production at 270days were 0.34∼0.91.

• Korean journal of food and cookery science
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• v.9 no.4
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• pp.323-328
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• 1993

Benzo(a)pyrene [B(a)P], one of the polycyclic aromatic hydrocarbons (PAHs) is known as a potent carcinogen. As lipid consumption increases recently, the toxic effect of overheated lipid foods and fats ＆ oils were reported increasingly. In this study, the contents of B(a)p, other PAHs and rancidities of soybean oil were determined, and then the proper heating temperature, time and frequency were recommended, The work was carried out using soybean oil heated at $180\pm$5^{\circ}C$$, $200\pm$5^{\circ}C$$, and $300\pm$5^{\circ}C$$,for 50 hours. Acid Value(AV) and Conjugated Diene Value of samples were determined. The contents of B(a)P and other PAHs contents of all samples were masured by HPLC/UV method. The results obtained were as follows; Each content of PAHs in the fresh soybean oil was: Pyr 1.093, B(a)A 0.986, Ch 1.147, DMBA 1.082, B(e)P 0.664, Per 1.135, B(a)P 0.146, DBA 1.053, 3-MC 0.05 rg/kg. When the soybean oil was heated at $180\pm$5^{\circ}C$$, for 10, 20, 30, and 50 hours, B(a)P conterlts in heated soybean oils were 0.391, 0.692, 0.451, and 0.372 $\mu\textrm{g}$/kg respectively. Acid value of them were 0.26, 0.26, 0.29, and 0.33, and conjugated diene value was 0.67, 0.76, 0.99, and 1.04, respectively. When the soybean oil was heated at $200\pm$5^{\circ}C$$,and $300\pm$5^{\circ}C$$,for 10, 20, 30, and 50 hours, B(a)P coiltents in soybean oil heated at $200\pm$5^{\circ}C$$,were 0.844, 0.512, 0.479 and 0.247 Ig/kg respectively, Acid value 0.22, 0.21, 0.23 and 0.51 and CDNV 0.39, 0.49, 3.27, and 3.89. B(a)P contents in soybean oil heated at $300\pm$5^{\circ}C$$,were 0.466, 0.706, 0.607 and 0.247$\mu\textrm{g}$/kg respectively, Acid value 0.47, 1.57, 3.90, and 6.42 and CDNV 0.65, 2.15, 3.00, and 3.88.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.10
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• pp.69-75
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• 2004

This work proposes an 8b 220 MS/s 230 mW 3-stage pipeline CMOS ADC with on-chip filers for temperature- and power- insensitive voltage references. The proposed RC low-pass filters improve switching noise performance and reduce reference settling time at heavy R & C loads without conventional off-chip large bypass capacitors. The prototype ABC fabricated in a 0.25 um CMOS occupies the active die area of 2.25 $\textrm{mm}^2$ and shows the measured DNL and INL of maximum 0.43 LSB and 0.82 LSB, respectively. The ADC maintains the SNDR of 43 dB and 41 dB up to the 110 MHz input at 200 MS/s and 220 MS/s, respectively, while the SNDR at the 500 MHz input is degraded as much as only 3 dB than the SNDR at the 110 MHz input.

• Korean Journal of Poultry Science
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• v.40 no.1
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• pp.17-23
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• 2013

This work was carried out to investigate the performance of early laying period of large-type Korean native ducks. One hundred sixty eight ducks were used in this work and divided into A and B strains (6 replications/strain, 14 birds/replication). The days at first egg of A and B strains were the age of 154.5 and 154.7 days, egg weights were 69.1 g and 65.5 g, and body weights were 3,187 g and 3,105 g at the period of laying the first egg, respectively. The days at sexual maturity of A and B strains were the age of 175.8 and 171.5 days, egg weights were 75.2 g and 74.9 g, and body weights were 3,245 g and 3,225 g at the period of laying the first egg, respectively. There were no significant differences on the day of first egg, the day of sexual maturity, egg weight and body weight at first egg and the sexual maturity, average body weight, and daily feed intake between A and B strains (P>0.05). The day of the sexual maturity of B strain was earlier than that of A strain (P<0.05). However, weekly body weight was the highest at the age of 28 weeks (P<0.05), and weekly feed intake increased after 26 weeks old (P<0.05). Egg production (%) of B strain was higher than that of A strain at the age of 22~24 weeks (P<0.05), but there was no significant difference on egg production (%) the other weeks. A number of egg laid of B strain was higher than A strain at 22~24 weeks old (P<0.05). Feed conversion ratio of A and B strains were 10.7 and 6.53 at 24~24 weeks old, respectively, so feed conversion ratio of A strain was higher than that of B strain (P<0.05). Weekly feed conversion ratio wes the highest at 20~22 weeks old, and significantly decreased until 24~24 weeks old, but were lowly maintained from the age of 24 weeks to the age of 30 weeks. These results provided the basic data on the record of early laying period of large-type Korean native ducks.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.5
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• pp.752-757
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• 1995

The effect of fermentation temperature on the changes of pH, acidity, salt content, color and vitamin C of mustard leaf kimchi during various storage days was investigated. The conditions of fermentation temperature were set at $4^{\circ}C$ (sample A) and $20^{\circ}C$ (sample B), and $4^{\circ}C$ after keeping at $20^{\circ}C$ for 12 hours(sample C) and $20^{\circ}C$ for 36 hours(sample D). As the fermentation proceeded, pH of sample stored at low temperature(sample A) was drop ped gradually from initial pH of 5.24 but there was great pH drop in the sample stored at high temperature(sample B, D). The salt content of the sample B at high temperature increased remarkably, and then the values showed D > A > C. The Humter values of L and a increased at the optimum ripening period, the higher the initial fermentation temperature(B) and the later the initial fermentation time at $20^{\circ}C$ those values, then decreased. The Hunter value of b constantly increased until day of 108. As fermentation time passed, the content of total vitamin C decreased to the range of 9.0mg% to 14.0mg% up to 24 days of fermentation, and at the optimum ripening period, it increased to the range of 14.0mg% to 22.0mg%, and at the fermentation period(until day 108), it decreased gradually.

• Imaging Science in Dentistry
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• v.31 no.1
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• pp.1-7
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• 2001

Purpose : To evaluate the usefulness of the reconstructed 3-dimensional image on the personal computer in comparison with that of the CT workstation by quantitative comparison and analysis. Materials and Methods : The spiral CT data obtained from 27 persons were transferred from the CT workstation to a personal computer, and they were reconstructed as 3-dimensional image on the personal computer using V-works 2.0/sup TM/. One observer obtained the 14 measurements on the reconstructed 3-dimensional image on both the CT workstation and the personal computer. Paired Nest was used to evaluate the intraobserver difference and the mean value of the each measurement on the CT workstation and the personal computer. Pearson correlation analysis and % incongruence were also performed. Results: I-Gn, N-Gn, N-A, N-Ns, B-A, and G-Op did not show any statistically significant difference (p>0.05), B-O, B-N, Eu-Eu, Zy-Zy, Biw, D-D, Orbrd R, and L had statistically significant difference (p<0.05), but the mean values of the differences of all measurements were below 2 mm, except for D-D. The value of correlation coefficient y was greater than 0.95 at I-Gn, N-Gn, N-A, N-Ns, B-A, B-N, G-Op, Eu-Eu, Zy-Zy, and Biw, and it was 0.75 at B-O, 0.78 at D-D, and 0.82 at both Orbrd Rand L. The % incongruence was below 4% at I-Gn, N-Gn, N-A, N-Ns, B-A, B-N, G-Op, Eu-Eu, Zy-Zy, and Biw, and 7.18%, 10.78%, 4.97%, 5.89% at B-O, D-D, Orbrd Rand L respectively. Conclusion : It can be considered that the utilization of the personal computer has great usefulness in reconstruction of the 3-dimensional image when it comes to the economics, accessibility and convenience, except for thin bones and the landmarks which are difficult to be located.

• Journal of Marine Life Science
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• v.3 no.2
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• pp.81-86
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• 2018

The purpose of this study is to determine the effects of vibration on primary (e.g. plasma cortisol), secondary (e.g. plasma glucose, aspartate aminotransferase (AST), alanine aminotransferase (ALT), Na⁺, K⁺ and Cl^- and tertiary (e.g. mortality) stress responses in cultured eel, Anguilla japonica. For this purpose, three groups (including one control group and two stress groups) were set up. The control group was made exposed to vibration corresponding to 48 decibel (dB, V) (produced using electric vibrators) for 15 minutes per hour every day, and the two stress groups was made exposed to vibration corresponding to 58 and 68 dB (V) (produced using the same electric vibrators), equally, for 15 minutes per hour every day. Blood was sampled at day 0 (before starting vibration stress tests, BS), and days 1, 3, 5, 7, 9 and 11 (after starting vibration stress tests). As a result, plasma cortisol showed trend to continuously rise by consecutive stress from 4.1±0.1 ng/ml in BS. In 48 dB group (control), cortisol showed the highest level with 7.6±0.9 ng/ml after 7 days (p<0.05), but at 9 and 11 days was not significantly compared with BS level. In 58 dB group, the cortisol showed the highest level with 43.1±4.8 ng/ml after 1st day. Cortisol of 68 dB group increased significantly during the experimental period (14.4±2.3~32.0±5.7 ng/ml) (p<0.05). In 58, and 68 dB groups during the experimental period differed significantly compared to 48 group (p<0.05). Glucose in 48 dB were increased from 42.0 ±5.7 (BS) to 52.5±2.1 (1 day), the level was not significantly from 1 to 11 days. Glucose in 58 and 68 dB groups was increased significantly than BS during experimental period (p<0.05). K⁺ in 68 dB increased significantly (p<0.05) from 2.3±0.2 mE/ql (BS) to 3.3±0.5 mE/ql at 5 days. In 48 and 58 dB groups during the experimental period differed significantly (p<0.05). Na⁺ and Cl^- levels were not differed significantly during the experimental period. AST and ALT in 58 and 68 dB groups showed trend to continuously rise by consecutive stress. At 7 and 9 days in AST, between 48, 58 and 68 dB groups differed significantly (p<0.05). In 48, 58 and 68 dB groups at 1 day, blood hematocrit increased significantly higher than BS. The 11 days after vibration stress, the mortality in 48, 58 and 68 dB groups was 1.1, 5.1 and 5.8%, respectively. The present results have shown that A. japonica exhibited ''typical'' physiological responses when exposed to chronic vibration stress. These data suggested that chronic vibration stress caused substantial stress in the fish; especially the persisting elevated plasma AST and ALT levels observed would be expected to adverse effect. In conclusion, chronic vibration stress could greatly affects the hematological characteristics in A. japonica.