• Food Science of Animal Resources
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• v.28 no.3
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• pp.327-332
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• 2008

This study was conducted to evaluate the effects of dietary Bacillus subtilis on meat quality, growth performance and fecal malodor gas emission in finishing pigs. Thirty-six pigs (Landrace ${\times}$ Yorkshire ${\times}$ Duroc, $83.53{\pm}1.01\;kg$ average initial body weight) were used in a 35 d growth assay. Dietary treatments were 1) CON (basal diet), 2) B1 (basal diet + B. subtilis 0.1%) and 3) B2 (basal diet + B. subtilis 0.2%). The pigs were distributed into four pigs per pen with three replicate pens per treatments by completely randomized design. For the entire period, the final weight, ADO, ADFI and gain/feed were not significantly different among the treatments. There were no significant differences in meat quality (sensory evalution, meat color, TBARS, water holding capacity, drip loss, cooking loss and M. longissimus dorsi area) among the treatments. $H_2S$ was significantly decreased in B2 treatment compared to CON and B1 treatments (p<0.05). However, ammonia, mercaptans and acetic acid were not significantly different among the treatments. In conclusion, B. subtilis 0.2% treatments decreased fecal $H_2S$ gas emission in finishing pigs.

• The Korean Journal of Malacology
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• v.24 no.2
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• pp.143-151
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• 2008

We studied the management policy for Haliotis diversicolor fisheries in the coastal area of Sungsanpo using Yield-per-recruit model from 2004 to 2006. The age at first capture($t_c$) and fishing mortality(F) annually estimated during the study period decreased and increased, respectively. The maximum yield-per-recruit in 2004 was increased by increasing $t_c$ from the 2.012 year of current $t_c$ to 2.7 year or increasing F from the 0.574/year of current F to 0.800/year, and that in 2005 was increased by increasing $t_c$ from the 1.946 year of current $t_c$ to 2.5 year or increasing F from the 0.578/year of current F to 0.880/year. In 2006, the maximum yield-per-recruit was increased by increasing $t_c$ from the 1.926year of current $t_c$ to 3.1 year or decreasing F from the 1.088/year of current F to 0.810/year. Further, although the current F in 2004 and 2005 was lower than the estimated $F_{MAX}$, that in 2006 was higher than the estimated $F_{MAX}$. These results indicate that the likelihood of growth overfishing with increasing catch of smaller H. diversicolor in 2006 was greater than in 2004 and 2005. As action that could prevent growth overfishing in fisheries management of H. diversicolor, increasing for the current $t_c$ could be a more appropriate policy because the artificial decrease of the number of woman divers related F is actually difficult.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.517-528
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• 2007

Domestic or international existing researches regarding rail damage factors are focused on laying, vehicle conditions, driving speed and driving habits and overlook characteristics of track structure (elasticity, maintenance etc). Also in ballast track, as there is no special lateral spring stiffness of track also called as ballast lateral resistance in concrete track, generally, existing study shows concrete track has 2 time shorter life cycle for rail replacement than ballast track due to abrasion. As a result of domestic concrete track design and operation performance review, concrete track elasticity is lower than track elasticity of ballast track resulting higher damage on rail and tracks. Generally, concrete track has advantage in track elasticity adjustment than ballast track and in case of Europe, in concrete track design, it is recommended to have same or higher performance range of vertical elastic stiffness of ballast track but domestically or internationally review on lateral spring stiffness of track is very minimal. Therefore, through analysis of service line track on site measurement and analysis on performance of maintenance, in this research, dynamic characteristic behaviors of commonly used ballast and concrete track are studied to infer elasticity of service line track and experimentally prove effects of track lateral spring stiffness that influence curved rail damage as well as correlation between track elasticity by track system and rail damage to propose importance of appropriate elastic stiffness level for concrete and ballast track.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.3
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• pp.251-256
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• 1981

Silage yield and nutritional values of a locally collected Korean corn line with high tillering and earing characteristics were investigated at plant densities from 2778 to 8333 plants/ l0a. This line and a non-tillering and nonprolific corn as a check were grown at four plant densities and at three planting dates. The Korean local line abbreviated as MET had the highest dry matter per l0a. The highest dry matter of the MET line compared with the check hybrid was due to the highest dry leaf weight of the MET line. The highest dry leaf weight of the MET line was due to the increased number of tillers of the MET line. Other plant parts such as ear weight, kernel weight and cob weight of the MET line were lower than those of the check hybrid. The dry husk weight per l0a of the MET line was higher than that of the check hybrid, probably due to the increased number of ears in the MET line. The total embryo production per 10 a of the MET line was significantly higher than that of the check hybrid. The increased portion of embryo of the MET line is probably responsible for the higher TON values of the MET line. No interaction between variety x planting dates or planting density was found, indicating that the MET line and check hybrid were both the same in effects of planting dates and densities. Both line and hybrid showed the highest dry matter production when the planting density was high and planting dates was early. When silage was made from either MET line or check hybrid the nutritional values in terms of crude protein, crude fat, fiber, and ash contents of the MET line were similar to those of the check hybrid. But the TON of the MET line was higher than that of the check hybrid, while the OCP of the MET line lower than that of the check hybrid. Amino acid contents of the MET line were also comparable to those of the check hybrid, while lysine content of the MET line was 10% higher than that of the check hybrid.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.3
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• pp.375-382
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• 1986

This study was carried out to obtain the basic information for the clarification of spring growth habits mechanism of naked barleys. The isozyme patterns and activities of peroxidase in the young spike and leaf blade were analyzed during the differentiation and development of young spike. The characteristic differences between the normal and rosetted type were in c and g isozymes in young spike, and in i isozyme in the leaf blade. In the normal type, c and i isozymes disappeared at the stage of spi-kelet differentiation, g isozyme at the stage of flolet differentiation. But, in the rosetted type, those three isozymes remained in dark stained condition until the time of final sampling. Especially, those three isozymes were higher in the rosetted type than those in the normal type even at the stage of bract differentiation(BDS), just prior to the reproductive stage. The activities of peroxidase decreased slowly after BDS in the young spike and leaf blade in the normal type, While, in the rosetted type, increased linearly, and the degree of increasing was remarkable in the young spike. It was interesting that the degree of activities in young spike was higher in the rosetted type than that in the normal type even at BDS. From the above results, the remarkable differences of the isozyme patterns and activities at BDS between the normal and rosetted type were considered to be the physiological expression of the varieties concerned with the degree of spring growth habits.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.spc1
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• pp.37-40
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• 2005

In order to find out better cultivation practices in mid-mountainous area to produce high quality rice, an experiment involving seven nitrogen fertilizer rates and three varieties was carried out, during past two years$(2003\~2004)$. There was an interaction effect on palatability of milled rice between nitrogen fertilizer rate and variety. The palatability of Junambyeo grown by the treatment of nitrogen fertilizer yale wasn't different across the rates significantly, but Hwayongbyeo's palatability grown by 0 kg/ha nitrogen treatment was better than 50, 70,170 kg/ha, and Sangmibyeo's palatability grown by 70 kg/ha nitrogen treatment was better than 90, 110, 140, 170 kg/ha. Amylose content of milled rice was showed without a significant difference between nitrogen fertilizer rate, but in between variety, the amylose content of Sangmibyeo was lower than Hwayongbyeo's, also Hwayongbyeo's amylose content was lower than Junambyeo's. Protein content of milled rice was showed an interaction effect between nitrogen fertilizer rate and variety. The protein content of Hwayongbyeo and Junambyeo grown by the treatment of nitrogen fertilizer rate wasn't different across the fertilizer yale significantly, but Sangmibyeo's protein content grown by 0 kg/ha nitrogen treatment was lower than the rest of treatments, and it's protein content grown by 50, 70, 90 and 110 kg/ha nitrogen treatment was lower than 140 and 170 kg/ha. Bead rice yield of milled rice grown by lower nitrogen fertilizer rate, was lower than that grown by higher nitrogen fertilizer rate. In a conclusion gathering all above the results to produce high quality rice in Mid-mountainous area, the applicative nitrogen fertilizer rate was 70 kg per ha for Sangmibyeo, 110 kg/ha for Hwayongbyeo and 140 kg/ha for Junambyeo, in considering with head rice yield, palatability, amylose${\cdot}$protein content and productivity.

• Economic and Environmental Geology
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• v.28 no.4
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• pp.351-367
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• 1995

The elemental geochemistry and oxygen isotopes of illite/smectite (I/S) have been studied in relationship to the mineralogical trend in the Reindeer D-27 well, Beaufort-Mackenzie Basin. The increase in concentrations of $K_2O$, Rb and rare earth elements (REE), the decrease in concentrations of tetrahedral elements such as Mg, Ti, Sc, Zn and Zr, and the increase in concentrations of tetrahedral elements such as Be and V can be related to I/S compositions that vary systematically with depth. Layer formulae of S- and I-layers are estimated as $[Al_{1.57}Fe_{.19}Mg_{.31}Ti_{.07}][Si_{3.84}Al_{.16}]O_{10}(OH)_2$ and $[Al_{1.84}Mg_{.16}][Si_{3.33}Al_{.67}]O_{10}(OH)_2$, respectively. The mobilization of REE appears to occur during illitization. The increase in concentrations of REE, especially La and Ce, with depth is probably linked to incorporation of ions with high valency (e.g. $V^{5+}$) in tetrahedral sites. The excess valency due to V is partly counter-balanced by ions with low valency (e.g. $Be^{2+}$) and, in turn, the local valency deficiency caused by $Be^{2+}$ could be compensated by high-charge interlayer cations such as REE (＋3). ${\delta}^{18}O$ values of I/S range from 2.91 to 15.72‰ (SMOW), and increase with depth, contrasting to trends observed in the Gulf Coast and elsewhere. The increase in ${\delta}^{18}O$ of I/S results from the rapid increase in ${\delta}^{18}O$ of pore water that overcomes the decrease in temperature-dependent fractionation values with increasing burial depth (${\delta}^{18}O_{pore\;water}>-d{\Delta}/_{I/S-water};\;d{\delta}^{18}O_{I/S}>0$). Calculated ${\delta}^{18}O$ values of pore water in equilibrium with I/S suggest that the original water was probably meteoric water. The stratification of pore water is postulated from the presence of an isotopically light interval, about 450m thick. The depth range of the isotopically light zone overlaps, but does not coincide with the interval of lowered I-content and $K_2O$ concentrations, suggesting that oxygens may have been exchanged independently of mineralogical and geochemical reactions.

• Journal of Korean Society of Transportation
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• v.20 no.5
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• pp.113-130
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• 2002

In this paper, we developed DNL(Dynamic Network Loading) model based on Moving cell theory to analyze the dynamic characteristics of traffic flow in congested network. In this paper vehicles entered into link at same interval would construct one cell, and the cells moved according to Cell following rule. In the past researches relating to DNL model a continuous single link is separated into two sections such as running section and queuing section to describe physical queue so that various dynamic states generated in real link are only simplified by running and queuing state. However, the approach has some difficulties in simulating various dynamic flow characteristics. To overcome these problems, we present Moving cell theory which is developed by combining Car following theory and Lagrangian method mainly using for the analysis of air pollutants dispersion. In Moving cell theory platoons are represented by cells and each cell is processed by Cell following theory. This type of simulation model is firstly presented by Cremer et al(1999). However they did not develop merging and diverging model because their model was applied to basic freeway section. Moreover they set the number of vehicles which can be included in one cell in one interval so this formulation cant apply to signalized intersection in urban network. To solve these difficulties we develop new approach using Moving cell theory and simulate traffic flow dynamics continuously by movement and state transition of the cells. The developed model are played on simple network including merging and diverging section and it shows improved abilities to describe flow dynamics comparing past DNL models.

• Journal of Korean Society of Transportation
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• v.20 no.5
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• pp.33-43
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• 2002

Travel choice behavior is affected by real-time traffic information. Recently, in urban area, real-time traffic information is provided by several instruments such as transportation broadcasting, internet PC network and variable message sign, etc. Furthermore, it has been increasing for urban travelers to use real-time traffic information provided by several instruments. The purpose of this study is to analyze the effects of advanced traveler information on urban worker's travel choice behavior. Among several Advanced Traveler Information System(ATIS) employed in urban area. This study focuses on examining the effects of transportation broadcasting on urban worker's travel choice behavior. This study attempts to examine traveler's mode change behavior in the pre-trip stage and traveler's route change behavior in the on-route stage. For this study, the survey data collected from Daegu City in 2000 is used. For empirical analysis, several nested logit models are estimated, and among them, the best models are reported in this paper. Furthermore, based on the empirical models estimated for this research, important findings and their policy implications are discussed.

• Korean Journal of Soil Science and Fertilizer
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• v.25 no.3
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• pp.242-248
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• 1992

This study was carried out to investigate the effects of root-zone temperature in hydroponics on the plant growth and nutrient uptake of lettuce(Lactuca sativa L), tomato (Lycopersicon esculentum Mill), and cucumber (Cucumis sativus L). Respiration rate in roots increased with increase in root-zone temperature. At $10^{\circ}C$ of root-zone temperature, respiration rate in lettuce root was higher than those in tomato and cucumber. Increasing rate of root respiration in tomato with increase in root-zone temperature was greater than those in lettuce and cucumber. The lowest dry weight and leaf area of the crops studied were obtained at $10^{\circ}C$ of root-zone temperature, but they were not different between 20 and $30^{\circ}C$. Increase in root-zone temperature generally resulted in increase in T/R ratio and net assimilation rate. At the low root-zone temperature, root growth and leaf area of tomato and cucumber were severely affected. Relative growth rates of lettuce and cucumber were also greatly reduced by the low root-zone temperature. Contents of N, P, K, Ca, and Mg in the crops increased as root-zone temperature increased from 10 to $20^{\circ}C$, whereas only Ca content in tomato and cucumber increased with increase in root-zone temperature to $30^{\circ}C$. Remarkably low contents of P and Mg in the crops were found at the low root-zone temperature. Inhibition of plant growth and nutrient uptake due to low root-zone temperature was much greater in cucumber than in lettuce and tomato.