• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.1
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• pp.9-14
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• 2004

In this paper, temperature dependence of effective ionization coefficient in Si is formulated as a single polynomial function of temperature, which allows analytical expressions for breakdown voltage of Si $p^+n$ junction as a function of temperature. The analytical breakdown voltages agree well with the simulation as well as the experimental ones reported within $3\%$ in error for the doping concentrations in the range of $10^{14}cm^{-3}{\~} 10^{17}cm^{-3}$ at 100K, 300K and 500K.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.48 no.4
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• pp.226-231
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• 1999

Temperature dependence of effective ionization coefficients in GaAs is formulated as a single polynomial function of temperature, which allows analytical expressions for breakdown voltage of GaAs $p^+n$ junctions as a function of temperature. At 300 K, extracted effective ionization coefficient of GaAs $p^+n$ junction especially agrees well with the published result of <111> oriented GaAs. The analytic results agree with the simulation as well as the experimental ones reported within 10% in error for the doping concentrations in the range of $10_{14}cm_{-3}~10_{17}cm_{-3}$ at 100 K, 300 K and 500 K.

• Journal of The Korean Society of Grassland and Forage Science
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• v.11 no.4
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• pp.222-229
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• 1991

This experiment was carried out to determine the effect of improvement of oversown pastures, treated with four nitrogen(N) application levels(0, 100, 200, 300 kg/ha) and three species mixtures (A: orchardgrass+ladino clover; B: orchardgrass+ladino clover+perennial ryegrass; C: orchardgrass+ladino clover+perennial ryegrass+Italian ryegrass). The establishment of perennial ryegrass, Italian ryegrass, and ladino clover were increased with increased N applications, but the ryegrass mixed with orchardgrass and ladino clover decreased the establishment of ladino clover. With the increase of N application levels, orchardgrass, perennial ryegrass and Italian ryegrass in comparison on botanical composition were getting better, while the native plants established already were decreased. The botanical composition of newly sown pasture plants was increased as cutting times progressed. The dry matter(DM) yield of pasture species increased significantly with N application up to 300 kg/ha. There was no significance among mixture treatments, although the DM yield of basic treatment(orchardgrass+ladino clover) was higher than other treatments. However, when compared DM yields on each cutting times, newly oversown pastures in A treatment was shown to be significantly higher only on 2nd cutting time than other treatments(P<0.05). The DM yield of native plants survived in basic species mixture was significantly less than those of other mixtures(P<0.05). Results of this study indicate that for improving oversown pastures, at least 300 kg/ha N application should be applied, and basic mixture (orchardgrass+ladino clover) has more advantage than treatments mixed with ryegrass.

• Food Science and Preservation
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• v.9 no.1
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• pp.109-113
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• 2002

The purpose of this study was to investigate antioxidative and nitrite scavenging activities of extracts of Cordyceps militaris. Fruiting body and mycelia of artificially cultivated Cordyceps militaris were extracted with water and 70% ethanol. In Cordyceps militaris mycelia, electron donating ability (EDA) of water extract ranged from 37% to 47% and ethanol extract ranged from 57% to 70% at 300∼1,000 ppm. In Cordyceps militaris fruiting body, EDA of water extract and ethanol extract were similar, ranged from 19% to 48% at 300-1,000 ppm. Nitrite scavenging ability (NSA) of extracts measured at various pH (1.2, 3.0, 4.2, 6.0) was the highest at pH 1.2 and decreased with increasing pH, suggesting it is pH dependent. In Cordyceps militaris mycelia, NSA of water extract 1,000 ppm was 23% and that of ethanol extract 1,000 ppm was 37% at pH 17. In Cordyceps militaris fruiting body, NSA of water extract 1,000 ppd was 12% and that of ethanol extract 1,000 ppm was 37% at pH 1.2. EDA and NSA of Cordyceps milituis were higher in extract of mycelia than fruiting beds and higher in ethanol extract than water extract of each part.

• Korean Journal of Poultry Science
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• v.35 no.2
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• pp.143-151
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• 2008

This study was conducted to identify the correlation of bacterial phytase ($Transphos^{(R)}$) to the calcium level in feed. Of all 21-week-old 720 HyLine brown laying hens, 2 birds of similar weight were placed on each individual cage. The experiment was conducted by $3{\times}2{\times}3$ factorial design with including 3 different levels of phytase (0, 300, and 1,000 DPU/kg), 2 different levels of calcium (3.5% and 4.0%), and 3 different levels of no NPP addition 0% (0.095 NPP), 0.5% (0.185% NPP), and 1.0% (0.275% NPP). The feeding trial maintained the ME level of 2,800 kcal/kg and 16% for crude protein. The diet was fed ad libitum and 17 hours of lighting was provided throughout the experimental period. Egg production seemed to increase, in the 300 DPU of bacterial phytase added group and the cracked egg tended to reduce in Transphos added group. The egg productivity between treatment groups did not show significant difference by dietary calcium level, whereas non NPP added group (0.095% NPP) was found to be low compared to NPP added groups (P<0.05). The highest mean egg weight and the highest daily egg mass were detected in 300 DPU phytase added group. Although the mean egg weight was significantly higher in treatment groups fed with 3.5% calcium containing feeds (P<0.05), daily egg mass was no among treatment groups. The mean egg weight and daily egg mass were the lowest in non NPP added group (0.095% NPP) compared to other treatment groups (P<0.05). The feed intake showed similar pattern regardless of the bacterial phytase and calcium levels in the diet. However, the treatment groups fed diets containing NPP level of 0.275% and 0.165% showed significantly higher feed intake than the group fed with 0.095% NPP (P<0.05). Although the feed conversion was not affected by calcium and NPP levels in the diet, the most improved result was obtained from 300 DPU phytase added group (P<0.05). The eggshell breaking strength and thickness increased as dietary calcium level increase the level of calcium increases in diet. The treatment groups fed diet containing 0.275% and 0.165% NPP revealed to show improvement in eggshell breaking strength and yolk color index compared to the NPP non added (0.095% NPP) treatment group. The result of the present study suggests that the appropriate level of microbial phytase is 300 DPU and at this level, tricalciumphosphate supplementation in feed can be reduced to 40% of NRC recommendation. Higher calcium level in feed fail to show synergistic effect by adding microbial phytase.

• Korean Journal of Pharmacognosy
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• v.25 no.3
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• pp.258-263
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• 1994

Ohjuksan has been used for the treatment of cold and pantalgia in traditional medicine. The anti-inflammatory activity of the aqueous extract from Ohjuksan (OJSE) was investigated utilizing acetic acid-induced edema and adjuvant arthritis in rats. The effects of this agent on acute toxicity and acetic acid-induced writhing syndrome in mice were also examined. OJSE did not showed acute toxicity at 2400mg/kg (p.o.) and 1200mg/kg(i.p.) body weight. It was also showed to have significant analgesic action on the writhing syndrome in mice induced by 0.7% acetic acid at 300,600mg/kg body weight. It showed anti-inflammatory activity in 5% acetic acid-induced edema and adjuvant arthritis with oral administration in rats and exhibited significant preventive effect on edema at 300 and 600mg/kg(p<0.01). In the method of adjuvant arthritis, orally administered for 19 days, it inhibited the hind paw edema in rats with 300 and 600 mg/kg body weight from 5 th day to 19th day. These results suggest that OJSE had analgesic and anti-inflammatory action.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.2
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• pp.91-95
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• 2012

ZnO thin films were deposited on p-type 4H-SiC substrate by pulsed laser deposition. ZnO nanowires were formed on p-type 4H-SiC substrate by furnace. Ti/Au electrodes were deposited on ZnO thin film/SiC and ZnO nanowire/SiC structures, respectively. Structural and crystallographical properties of the fabricated ZnO thin film/SiC and ZnO nanowire/SiC structures were investigated by field emission scanning electron microscope and X-ray diffraction. In this work, resistance and sensitivity of ZnO thin film/SiC gas sensor and ZnO nanowire/SiC gas sensor were measured at $300^{\circ}C$ with various CO gas concentrations (0%, 90%, 70%, and 50%). Resistance of gas sensor decreases at CO gas atmosphere. Sensitivity of ZnO nanowire/SiC gas sensor is twice as big as sensitivity of ZnO thin film/SiC gas sensor.

• The Journal of Korean Academy of Prosthodontics
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• v.29 no.1
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• pp.281-287
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• 1991

This study was designed to investigate the influence of the clasp arm length on the change of retentive force with repeated placement or removal. The author measured the retentive force of Akers clasp and I-bar clasp in the depth of undercut 0.5mm, 0.25mm, respectively, varying the length of clasp arm, that is, 10mm, 14mm, 17mm in Akers clasp and 16mm, 18mm, 20mm in I-bar clasp. The retentive force was measured just before the placement of removal, after 100 times repeated placement or removal, after 300 times repeated placement or removal. The obtained results were as follows : 1. The shorter the clasp arm, the greater retention in Akers clasp and I-bar clasp(p<0.05). 2. There was decreased retentive force of Akers clasp and I-bar clasp after 300 times repeated placement or removal(p.<0.005). 3. The decreasing rate of retentive force in Akers clasp with 10mm was higher than that with 17mm, after 300 times repeated placement or removal, but there was no statistica difference(p>0.05).

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.2
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• pp.201-207
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• 1998

One growth trial and one digestibility trial were conducted to evaluate the nutritional value of HP300, a commercially processed soybean meal product for weanling pigs. Dried whey, fish meal and/or full fat extruded soybeans (FFES) as well as portions of soybean meal (SBM) were replaced with HP300 in weanling pig diets. The objectives were to investigate the effects of HP300 on growth performance, digestibility, ileal amino acid digestibility and blood amino acid concentration in weanling pigs. One hundred and twenty crossbred $(Duroc{\times}Beijing\;Black{\times}Landrace)$ pigs weaned at 28 days of age were used in the growth trial. The pigs were randomly allocated to five treatments, with three pens per treatment and eight pigs per pen. The trial duration was 28 days. The control (CTRL) diet contained no HP300; in treatments 2, 3 and 4, dried whey and fish meal were replaced by 3.0%, 7.5% and 10.5% HP300; in treatment 5, full fat extruded soybeans were replaced by 10.5% HP300 plus soybean oil to attain the same metabolic energy content as FFES. Five T-cannulated barrows were used in a digestibility trial with a $5{\times}5$ Latin square design to determine nitrogen retention and amino acid ileal digestibility of HP300 used alone or mixed with other ingredients. The results indicated that replacement of dried whey, fish meal, full fat extruded soybeans and a part of the soybean meal with HP300 in piglet diets improved average daily gain and feed conversion ratio (p < 0.05). There was a trend toward improved DM, crude protein and amino acid ileal digestibilities and improved protein and amino acid ileal digestibilities and improved protein net availability with the use of HP300 in swine diets.

• Journal of the Korean Magnetics Society
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• v.19 no.4
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• pp.133-137
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• 2009

$MnGeP_2$ thin films grown on GaAs exhibit room-temperature ferromagnetism with $T_C{\sim}$320 K, based on both magnetization and resistance measurements. The coercive fields at 5, 250, and 300 K are 3870, 1380 and 155 Oe, respectively. The anomalous Hall effect was observed, indicating spin polarization of the carriers. Hysteresis has been observed in both magnetoresistance and Hall measurements. The current-voltage characteristics of a $MnGeP_2$ film grown on an n-type GaAs substrate display semiconducting behavior.