• Structural Engineering and Mechanics
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• v.59 no.5
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• pp.853-866
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• 2016

This paper examines a methodology for computing the probability of structural failure of reinforced concrete beams subjected to fire. The significant load variables considered are dead load, sustained live load and fire temperature. Resistance is expressed in terms of moment capacity with random variables taken as yield strength of steel, concrete class (or grade of concrete), beam width and depth. The flexural capacity is determined based on the design equations recommended in Indian standard IS456:2000. Simplified method named $500^{\circ}C$ isotherm method detailed in Eurocode 2 is incorporated for fire design. A transient thermal analysis is conducted using finite element software ANSYS$^{(R)}$ Release15. Reliability is evaluated from the initial state to 4h of fire exposure based on the first order reliability method (FORM). A procedure is coded in MATLAB for finding the reliability index. This procedure is validated with available literature. The effect of various parameters like effective cover, yield strength of steel, grade of concrete, distribution of reinforcement bars and aggregate type on reliability indices are studied. Parameters like effective cover of concrete, yield strength of steel has a significant effect on reliability of beams. Different failure modes like limit state of flexure and limit state of shear are checked.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2001.07a
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• pp.226-231
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• 2001

• Korean Journal of Food Science and Technology
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• v.34 no.5
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• pp.846-855
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• 2002

Several soft white spring and winter wheat cultivars were evaluated by analyzing physicochemical properties such as Single Kernel Characterization System (SKCS), milling properties, Rapid Visco-Analyzer (RVA), mixograph pattern, and sugar-snap cookie-making potentialities. Results of SKCS revealed kernel hardness had a positive correlation coefficient with test weight $(r=0.497^{*})$ and near-infrared reflectance (NIR) hardness $(r=0.495^{*})$. SKCS kernel weight had a significantly high correlation of $r=0.942^{**}$ with SKCS kernel size. The test weight had significantly high correlations with straight-grade flour yield $(r=0.720^{**})$, break flour yield $(r=0.490^{*})$, flour ash content $(r=-0.781^{**})$, and milling score $(r=0.838^{**})$. The average RVA peak viscosity of the soft white winter wheat was higher (195.1 unit) than the soft white winter wheat varieties (135.7 unit). A correlation was found between RVA peak viscosity and swelling volume. Significant correlation coefficients were obtained among cookie properties, milling properties, protein content, and mixograph absorption. The cookie top grain score had a correlation coefficient of $r=0.447^{*}$ with swelling volume.

• Journal of The Korean Society of Grassland and Forage Science
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• v.5 no.3
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• pp.191-195
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• 1985

This field experiment was undertaken to assess the effects of three levels of inclination ($10^{\circ},\;20^{\circ},\;and\;30^{\circ}$) and four rates of $N-P_2O_2-K_2O$ (O-O-O, 14-10-20, 28-25-25, and 42-40-40kg/10a) on establishment, forage yield and quality and botanical composition of new established mixed grass-clover sward. This first part is concerned with the forage yield, yield component and botanical composition. The results obtained after a two-year experiment are summarized as follows: 1. Dry matter yields of mixed grass-clover sward were greatly decreased by increasing the inclination grade of hilly pasture, whereas it of weeds was not significantly influenced. Comparing with weeds, the establishment of introduced pastures was relatively low with increasing the grade of inclination. 2. By increasing the NPK rate, the yields of grasses and mixed forages and the rate of introduced pastures were greatly increased at all grades of inclination, whereas the change in the weed yield was not significant. 3. There were the differenced in the forage yield and yield component, and efficiency of fertilizers by the grade of inclination, which indicated the necessity of different management on the selection of suitable grass species, seeding rate, amount of fertilizer application, and the methods of grassland establishment, management and utilization.

• Journal of The Korean Society of Grassland and Forage Science
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• v.13 no.3
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• pp.195-202
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• 1993

This experiment was carried out to investigate the eft'ects of different seeding dates on the agronomic characteristics, forage yield and quality of fall sown cats(Avena sativa L.). The experiment was conducted at the forage experimental field, Seoul National University. Suweon in 1990. The results obtained are summarized as follows; 1. Present data indicated that plant and ear heights were decreased as the seeding date was delayed. Dry matter accumulation was increased due to the higher plant and ear heights. 1. When oats was seeded on August 20. the first heading and 50% heading dates were recorded on October 4 and 15, respectively. And when oats was seeded on August 25. the first heading and 5 0'!4 heading dates were observed on October 13 and 18. respectively. As seeding date was delayed for one day. the heading date was delayed for two days. 3. The dry mattcr percentage of oats seeded on August 20 was 20.1%, but that of oats seeded after August 10 was 15.1 to 16.7%. 4. According to the contents of CP. ADF and NDF, oats seeded on August 20 and 25 was evaluated to be the 3rd or 4th grade hay. and the other oats sceded after August 15 was recorded the 2nd or 3rd grade hay as proposed by AFGC. 5. There are no significant dry matter yield differences among the seeding dates of oats such as August 20, 25 and 30. but a significant yield difference was recorded between oats seeded in August and September. The same trend as the dry matter yield was observed in in vitro digestible dry matter and crude protein yields of oats seeded in August and September. According to the results. early seeding of early matuaring oats may be a better option than late seeding after August 30 for silage or hay production following silage corn harvest in the middle northern area of Korea.

• The Korean Journal of Cytopathology
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• v.6 no.1
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• pp.18-26
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• 1995

In order to compare cytologic findings ol breast carcinoma in fine needle aspiration cytology (FANC) with histologic findings and prognostic factors including histologic grading, lymph node metastasis and stage, 79 cases of infiltrating ductal carcinoma diagnosed by FANC and confirmed by histology were analysed. We especially attempted to col relate nuclear grade, cellularity and smear pattern with histologic grade, type, status of lymph node metastasis and stage. The results are as fellows. 1. High nuclear grade was correlated with high histologic grade, lymph node metastasis and advanced stage. 2. Individual cell pattern was more frequently identified in high histologic grade and scirrhous or solid-tubular type than in low histolgic grade and papillotubular type. 3. Cellularity increased with higher histologic grade and lymph node metastsis. However cellularity was low in scirrhous type. 4. There is no relationship between nuclear grade and histologic type, between smear pattern and lymph node metastasis or stage, and between cellularity and stage. These results suggest that cytologic findings of breast carcinoma such as nuclear grade, cellularity and smear pattern are indicative of histologic findings in relation to histolgic grade and type. Especially, nuclear grade of FANC may yield valuable prognostic information.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.8
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• pp.1083-1094
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• 2016

Carcass and price traits of 72,969 Hanwoo cows, bulls and steers aged 16 to 80 months at slaughter collected from 2002 to 2013 at 75 beef packing plants in Korea were analyzed to determine heritability, correlation and breeding value using the Multi-Trait restricted maximum likelihood (REML) animal model procedure. The traits included carcass measurements, scores and grades at 24 h postmortem and bid prices at auction. Relatively high heritability was found for maturity ($0.41{\pm}0.031$), while moderate heritability estimates were obtained for backfat thickness ($0.20{\pm}0.018$), longissimus muscle (LM) area ($0.23{\pm}0.020$), carcass weight ($0.28{\pm}0.019$), yield index ($0.20{\pm}0.018$), yield grade ($0.16{\pm}0.017$), marbling ($0.28{\pm}0.021$), texture ($0.14{\pm}0.016$), quality grade ($0.26{\pm}0.016$) and price/kg ($0.24{\pm}0.025$). Relatively low heritability estimates were observed for meat color ($0.06{\pm}0.013$) and fat color ($0.06{\pm}0.012$). Heritability estimates for most traits were lower than those in the literature. Genetic correlations of carcass measurements with characteristic scores or quality grade of carcass ranged from -0.27 to +0.21. Genetic correlations of yield grade with backfat thickness, LM area and carcass weight were 0.91, -0.43, and -0.09, respectively. Genetic correlations of quality grade with scores of marbling, meat color, fat color and texture were -0.99, 0.48, 0.47, and 0.98, respectively. Genetic correlations of price/kg with LM area, carcass weight, marbling, meat color, texture and maturity were 0.57, 0.64, 0.76, -0.41, -0.79, and -0.42, respectively. Genetic correlations of carcass price with LM area, carcass weight, marbling and texture were 0.61, 0.57, 0.64, and -0.73, respectively, with standard errors ranging from ${\pm}0.047$ to ${\pm}0.058$. The mean carcass weight breeding values increased by more than 8 kg, whereas the mean marbling scores decreased by approximately 0.2 from 2000 through 2009. Overall, the results suggest that genetic improvement of productivity and carcass quality could be obtained under the national scale breeding scheme of Korea for Hanwoo and that continuous efforts to improve the breeding scheme should be made to increase genetic progress.

• Restorative Dentistry and Endodontics
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• v.35 no.1
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• pp.13-19
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• 2010

The purpose of this study was to compare the microshear bond strength of a self-etching primer adhesive to dentin prepared with different diamond points, carbide burs and SiC papers, and also to determine which SiC paper yield similar strength to that of dentinal surface prepared with points or burs. Fifty-six human molar were sectioned to expose the occlusal dentinal surfaces of crowns and slabs of 1.2 mm thick were made. Dentinal surfaces were removed with three diamond points, two carbide burs, and three SiC papers. They were divided into one of eight equal groups (n = 7); Group 1: standard diamond point(TF-12), Group 2: fine diamond point (TF-12F), Group 3: extrafine diamond point (TF-12EF), Group 4: plain-cut carbide bur (no. 245), Group 5: cross-cut carbide bur (no. 557), Group 6 : P 120-grade SiC paper, Group 7: P 220-grade SiC paper, Group 8: P 800-grade SiC paper. Clearfil SE Bond was applied on dentinal surface and Clearfil AP-X was placed on dentinal surface using Tygon tubes. After the bonded specimens were subjected to uSBS testing, the mean uSBS (n = 20 for each group) was statistically compared using one-way ANOV A and Tukey HSD test. In conclusion, the use of extrafine diamond point is recommended for improved bonding of Clearfil SE Bond to dentin. Also the use of P 220-grade SiC paper in vitro will be yield the results closer to dentinal surface prepared with fine diamond point or carbide burs in vivo.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.11
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• pp.118-123
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• 2017

To manufacture MG-Si (Metallurgical grade silicon) for use in various industries, Acid leaching experiments were performed to remove aluminum (Al) and iron (Fe), which are the most common impurities found in the silicon raw material. The silicon raw material was reacted with five types of acids (HCl, HF, H2SO4, HNO3, H3PO4) at 1, 2, 4, and 6M; 1M HF showed the highest Al and Fe removal rates, 97.9% and 95.2%, respectively. HF, however, resulted in an 18% reduced yield due to the silicon corrosion properties. To minimize the yield reduction, 2M HCl, which has a second removal ratio result, was mixed with 1M HF and applied to the silicon raw material. The experiment was conducted to select the optimal conditions for the mixed solution, which were $80^{\circ}C$ and 2hr. Under the optimal conditions, the residual Al and Fe concentrations were 141 ppmw and 93 ppmw, respectively, and it very easy to produce MG-Si with 3N grade purity.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.1
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• pp.1-5
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• 2003

Genetic parameters of live weight at slaughter (LWT), quantity index (QIX), yield grade (YGD), quality grade (QGD), pH of meat, and boiled meat tenderness in terms of mastication (BMAS), shear force (BSFR) and penetration (BPEN) in Hanwoo steers were estimated. Effects of sire, location and their interaction on these traits were also evaluated. Sire effects were found to be significant on all the traits studied except for pH and BSFR. The LWT, QIX and QGD were also significantly affected both by location and by interaction effect between sire${\times}$location. The BSFR and BPEN were significantly (p<0.01) affected by location but not significantly by sire${\times}$location interaction. The boiled meat tenderness and pH were negatively correlated ($r_g$ and $r_p$) with LWT, QIX and QGD. All the other traits were positively correlated with each other. Positive and high genetic correlation (+0.56) between LWT and QGD was obtained indicating that selection for LWT would improve QGD. The $h^2$ estimates were 0.43, 0.37, 0.37, 0.35 and 0.32 for QGD, LWT, pH, BSFR and BPEN, respectively.