• Journal of Animal Science and Technology
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• v.46 no.3
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• pp.387-396
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• 2004

This experiment was carried out to investigate the effects of dietary vitamin C and E on carcass characteristics of Hanwoo steers. Thirty seven Hanwoo steers were randomly assigned to one of four treatments. The four treatments were control(vitamin E 20 IU/kg feed), vitamin C(vitamin C 0.1%/kg feed and vitamin E 20 IU/kg feed), vitamin E(vitamin E 220 IU/kg feed) and vitamin C plus E(vitamin C 0.1%/kg feed and vitamin E 220 IU/kg feed). Hanwoo steers were fed experimental diets for 3 months of the last finishing period. Animals fed the diet containing vitamin C plus E had higher(P<0.05) yield grade than those fed the other diets but quality grade was not different between animals fed the control diet and vitamin-supplemented diets. Proximate analysis in longissimus dorsi was not different between animals fed the control diet and vitamin-supplemented diets. Vitamin C concentration in longissimus dorsi was higher (P<0.05) in the animals fed the vitamin C diet and the vitamin C plus E diet than in those fed the control diet and the vitamin E diet. Vitamin E concentration in longissimus dorsi was higher(P<0.05) in the animals fed the diet supplemented with vitamin E and the diet supplemented with vitamin C plus E than in those fed the control diet and the vitamin C diet. Animals fed the diet supplemented with vitamin C was higher(P<0.05) in myristic acid, palmitic acid, palmitoleic acid and oleic acid in the longissimus dorsi than those fed the other diets, but linoleic acid in longissimus dorsi was higher(P<0.05) in the animals fed the vitamin E diet than those fed the other diets. However, saturated fatty acid and unsaturated fatty acid were not different between animals fed the control diet and vitamin-supplemented diets.

• Korean Journal of Agricultural Science
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• v.23 no.2
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• pp.212-218
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• 1996

This study was conducted to investigate the effects of coculture for the development rate to morula/blastocyst stages of early porcine embryos, derived from oocytes matured and fertilized In vitro, with porcine cumulus cell monolayers(PCM) in the two different media, respectively. The rates of embryos developed to 2-, 4-, 8~16-cell and morula/blastocyst stage were 48.7, 40.5, 34.8 and 17.0% in Ham's F-10 with PCM, and 48.3, 35.6, 22.1, and 13.4% in TCM-HEPES with PCM, respectively. The above development rates to morula/blastocyst stages were significantly higher than those of the embryos cultured in the Ham's F-10 and TCM-HEPES without PCM(P<0.05). The in vitro development rates to the morula/blastocyst stage of I-cell embryos cultured in Ham's F-10 and TCM-HEPES without PCM were 0.0~1.0%. Especially, most of embryos were observed to arrest the development beyond 4-cell stages. As shown in the above results, the coculture of in vitro fertilized porcine embryos with PCM in the two different media enhanced the development of fertilized eggs to morula/blastocyst stages in vitro. However, we didn't find out any difference for the in vitro development to morula/blastocyst stages between Ham's F-10 and TCM-HEPES media.

• Korean Journal of Plant Resources
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• v.10 no.1
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• pp.86-93
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• 1997

In order to induce somatic embryogenesis from the stem explants and anther of Kalanchoe daigremontiana, the explants were cultured on MS medium supplemented with auxin (2,4-D, IAA, NAA) and/or cytokinin (BAP) for 8 weeks. Callus from explants was induced most efficiently on MS medium containing. 2.0mg/L NAA and 0.2mg/L BAP. Somatic embryogenesis in stem callus was formed by transfering embryogenic callus from induction media containing growth regulators to medium without growth regulators and then to the medium containing auxin and cytokinin (0.1 mg/L IAA and 1.0mg/L BAP). Callus formation occurred actively in the anthers at early uninucleate stage, and by low temperature pretreatment at $4^{\circ}C$ for 3days. Somatic embryogenesis from the anther callus was induced on MS medium containing 1.0mg/L NAA and 1.0mg/L BAP, 2.0mg/L NAA and 0.2mg/L BAP. The tetraploid of 5.4% was obtained among plants regenerated from anthers.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.31 no.1
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• pp.84-92
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• 1995

The methods by turning circle test and maneuvering indices have been used to study and evaluate the maneuverability of a ship. However recently many studies utilizing the GPS are made on the measurement of the turning circle and in the fishery and hydrographic survey. In this paper, the author carried out the turning circle test using the differential GPS and dumb card together, and compared the data measured by them and analyzed the accuracies of them to obtain the utility basic ones on the measurement of the turning circle by the DGPS. The main results area s follows : 1) To check the accuracies of the GPS, the circling experiments of 50m radius by the DGPS were made on the ground. The accuracies of turning circle measured by the DGPS were found to be very high as the errors of 1.5m. 2) the turning circle by the DGPS could be measured very accurately, by the seed, rudder angle, starboard and port respectively. 3) The turning circle measured by the dumb card was found to be measured accurately as much as the DGPS, when using large rudder angle, the turning circle was large, the turning circle by the dumb car could not be measured accurately on account of large error of bearing of compass. 4) The tactical diameters by the DGPS in case of the rudder angle 35。~5。, were found to be 2.6。15.0 times the Lpp of S.T HAELIM-3 at her slow speed 2.8~16.6 times her Lpp at her half speed, 3.1~17.4 times her Lpp at her full speed. The tactical diameter by the dumb card was found to be 2.4~9.5 times, 2.6~9.6 times, 3.2~12.2 times her Lpp respectively, in the above case and speed.

• Korean journal of applied entomology
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• v.24 no.4 s.65
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• pp.223-230
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• 1986

A series of experiments were carried out to evaluate the differences in susceptibility of the 13-aphidicidial insecticides in the green peach aphids(Myzus persicae) collected from 13 different localities. The aphids were reared and increased on the potted tobacco plants in the laboratory. The susceptibility to insecticides was compared at the $LC_{50}$ levels with the resistant ratio by a leaf-dip method with a laboratory strain reared for 2 years in the laboratory without exposure to insecticides. The susceptibility to the insecticides was greatly varied with the local strains. The local strains demonstrated relatively high resistance to the insecticides over the laboratory strain at the $LC_{50}$ level; in resistant fold, 2.3 to 519.0 to cypermenthrin, 2.3 to 494.5 to decamethrin, 2.8 to 442.4 to fenvalerate, 2.5 to 170.6 to formothion, 1.5 to 494.5 to decamethrin, 2.8 to 442.4 to fenvalerate, 2.5 to 170.6 to formothion, 1.5 to 231.8 to phosphamidon, 3.1 to 42.1 to monocrotophos, 1.0 to 30.9 to phenthoate+dimethoate, 1.8 to 21.0 to heptanophos, 2.1 to 24.8 to oxydemeton-methyl, 1.0 to 24.9 to thiometon, 1.6 to 4.7 acephate, 0.8 to 4.1 to pirimicarb.

• Korean Journal of Medicinal Crop Science
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• v.5 no.4
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• pp.289-293
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• 1997

The effects of plant regulators on direct somatic embryogenesis in liquid culture of Rehmannia glutinosa were investigated and the proper explant for direct somatic embryo formation was studied. Direct somatic embryos were induced from leaf segments culture in the MS liquid medium containing 0.5 mg/l of both IAA and NAA, while IBA of 1.0 mg/l was required for the same effect. Many somatic embryos were directly formed at the concentration of 2.0 mg/l cytokinin such as BA, kinetin and zeatin, but somatic embryogenesis was relatively poor at above or below this level. Relatively more somatic embryos were induced in the combination of 1.0mg/l IAA and 2.0mg/l zeatin. Formation of somatic embryos begun after 6 weeks on stem segments, while 7 weeks both on petiole and leaf. However, overall production of somatic embryos after 8 weeks was higher in leaf segment than that of stem segment.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.2
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• pp.99-107
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• 1997

The effect of easily decomposable organic carbon (methanol) application on the behavior of nitrogen derived from surface-applied urea in submerged soil was investigated. Two rates of urea (150 & $300kg-N\;ha^{-1}$) and three levels of methanol (2, 4, 8 ml) were applied to 10 g soil samples. The samples were incubated for 30 days under submerged conditions. The flood water and the soil were sampled for analysis of urea-N, $NH_4-N$ and $NO_3-N$ every 10 days. Urea-N in flood water and in soil at the rate of $150kg-N\;ha^{-1}$ and that in flood water at the rate of $300kg-N\;ha^{-1}$ were not detected but the urea-N concentration in soil at the rate of $300kg-N\;ha^{-1}$ with 8 ml methanol treatment was 4.7 on the 10th day from incubation. $NH_4-N$ concentrations in flood water and in soil increased with increasing urea application rates whereas they decreased with increasing methanol treatment. $NO_3-N$ concentration in flood water and in soil were similar regardless of the urea and methanol application rates. The total amount of $NH_4-N$ in flood water and in soil decreased with increasing methanol treatment, 0 ml & 2 ml, whereas the total amounts of $NO_3-N$ in both flood water and soil increased slightly at higher rates of methanol treatment, 4 ml & 8 ml. The total amount of $NH_4-N$ in both flood water and soil increased up to 20 days of incubation whereas that of $NO_3-N$ in flood water and in soil decreased over incubation time.

• Journal of the Korean Geotechnical Society
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• v.17 no.1
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• pp.109-118
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• 2001

대구지역은 광범위한 층리가 균일한 형태로 발견되는 지역으로 역학적인 이방성을 나타내고 있다. 이러한 이방성을 가진 지반은 지하 구조물의 거동이 등방과 다른 양상을 보이므로 이방성해석이 수행되어야 한다. 이에 본 연구에서 대구지역 셰일에 대해 암판정상 경암과 보통암에 대해 동일한 시료에서 등방과 이방상태의 탄성정수를 층리각도($\beta$)별로 산출하였고 이것을 바탕으로 하여 유한 요소법을 사용한 이방성 해석을 수행하였다. 해석결과 이방상태의 응력과 변위의 결과는 등방과 다름을 알 수 있었다. 변위는 층리각에 따라 등방에 비해 지표면에서 약 3배까지 증가하며, 록볼트는 최대 2.04배, 숏크리트는 2.93배 증가하게 나타난다. 또한, 측압계수(K$_{0}$)가 이방성 암반과 터널구조물에 미치는 영향을 알 수 있었다. 따라서, 본 지역과 같은 층리가 존재하는 지반의 구조물 건설에서 이방성해석이 필수적임을 알 수 있다.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.7
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• pp.516-522
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• 2011

The largest problem of domestic anaerobic digestion is low digestion efficiency. Reasons of the problem would be low organic matters input, low mixing efficiency in digestion tank, refractory excess sludge etc.. In this study, screw attached disk-type concentration system and a mechanical mixing system, solubilization facility improvements were performed to solve problems. Through these improvements, the sludge conc. of the concentrator increased 2.6-fold and the volume reduction efficiency was increased 3.0-fold. In addition, the dead-space is reduced by mechanical agitation. Anaerobic digester gas production in the digestion tank is increased from $193.8m^3$ to $386.0m^3$ per day. Digestion efficiency is improved to 54.6% from 47.6%. Digestion gas production is increased from $0.30Nm^3/kg$ VS to $0.42Nm^3/kg$ VS.

• Journal of the Korean Geotechnical Society
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• v.28 no.1
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• pp.67-77
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• 2012

In this study, a series of centrifuge shaking-table tests for a $3{\times}3$ group pile and a single pile applied by sinusoidal wave was performed in dry sand for various pile spacings, ranging from three to seven times the pile diameter. A comparison of centrifuge tests of both single pile and group pile showed that the lateral ground response of the group pile was smaller than that of the single pile. In addition, the reduction in subgrade reaction for the group pile increased with decreasing pile spacing. The side piles, that is, the 1st row and 3rd row piles showed identical dynamic p-y behavior and the center pile in the 2nd row caused a lower reduction effect compared with the 1st and 3rd row piles. From the comparison between the p-y curves of the 2nd row piles, it was found that the lateral ground response of the outer pile in the 2nd row was less than that of the center pile in the 2nd row. The p-multipliers for the side piles, for the center pile and for the outer pile ranged from 0.28 to 0.77, from 0.55 to 1.0 and from 0.39 to 0.87, respectively.