• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.2
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• pp.413-423
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• 1991

Multiaxial loading by combinations of tension-torsion-internal pressure have been applied to the thins-walled tubular specimens prepared from cold drawn tubes of SAE 1020 steel. Prior to the multiaxial loading, each specimen has been twisted to different shear strains. Uniaxial tensile yield stresses measured at different angles to the tube axis clearly show that the initial orthotropic symmetry is maintained during twisting. The orthotropy axes are observed to rotate with shear strains. The plane stress yield locus measured for each twisted specimens show that yield surface shape does not remain similar during twisting and thus anisotropic work hardening is not a function of only plastic work.

• International Journal of Industrial Entomology and Biomaterials
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• v.18 no.2
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• pp.135-138
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• 2009

Studies on the effect of different secondary nutrients in different doses on the leaf yield and biochemical constituents of Terminalia tomentosa revealed that secondary nutrients have promotary effect in increasing the leaf yield and foliar constituents of Terminalia tomentosa. Among all the treatments under study, foliar application of magnesium sulphate (2g/plant, w/v) is the best in respect of leaf yield and biochemical constituents of T. tomentosa. This treatment gave 29.15% increase in leaf yield over control. Chemoassay results further confirmed significant improvement in biochemical constituents. Except crude fibre, moisture, minerals, crude protein and total carbohydrate increased significantly over control.

• Magazine of the Korean Society of Agricultural Engineers
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• v.39 no.6
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• pp.31-40
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• 1997

Potential impacts for unfavourable weather conditions and the assessment of the magnitudes of their adverse effects on crop yields were studied. EPIC model was investigated for its capability on crop yield predictions for rice and soybean. Weather generationmodel was used to generate long-term climatic data. The model was verified with ohserved climate data of Suwon city. Fifty years weather data including abnormal conditions were generated and used for crop yield simulation by EPIC model. Crop yield probability function was derived from simulated crop yield data, which followed normal distribution. Probable crop yield reductions due to abnormal weather conditions were also analyzed.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.4
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• pp.67-75
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• 2011

Sulfuric acid hydrolysis is a typical approach for producing cellulose nanocrystals. The method has been widely used, but it has a disadvantage of low yield of cellulose nanocrystals compared to mechanical method. To expand the application of cellulose nanocrystals in practical, we should be able to produce them with higher yield and the controlled properties. In this study, therefore, we intended to investigate the effect of sulfuric acid hydrolysis condition on the characteristics of the prepared cellulose nanocrystals. The concentration of sulfuric acid, temperature and hydrolysis time were varied, and the yield as well as diverse properties including the morphology, size and zeta potential were examined. We could obtain cellulose nanocrystals up to 70% of yield and found that the properties were dependent on the reaction condition. It would be helpful to select an appropriate condition for producing cellulose nanocrystals.

• Structural Engineering and Mechanics
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• v.3 no.6
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• pp.529-539
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• 1995

The rigid-plastic yield-line analysis of isotropically reinforced concrete slabs acting in conjunction with torsionally weak supporting beams is developed as the lower-bound form of a linear programming formulation. The analysis is extended to consider geometric variation of chosen yield-line patterns by the technique of sequential linear programming. A strategy is followed of using a fine potential yield-line mesh to identify possible collapse modes, followed by analysis using a coarser, simplified mesh to refine the investigation and for use in conjunction with geometric optimization of the yield-line system. The method is shown to be effective for the analysis of three slabs of varying complexity. The modes detected by the fine and simplified analyses are not always similar but close agreement in load factors has been consistently obtained.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.4
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• pp.591-595
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• 2002

Three hundred thirty five progeny testing steers of Korean beef cattle were evaluated ultrasonically for back fat thickness (BFT), longissimus muscle area (LMA) and intramuscular fat (IF) before slaughter. Class measurements associated with the Korean yield grade and quality grade were also obtained. Residual standard deviation between ultrasonic estimates and carcass measurements of BFT, LMA were 1.49 mm and $0.96cm^2$. The linear correlation coefficients (p<0.01) between ultrasonic estimates and carcass measurements of BFT, LMA and IF were 0.75, 0.57 and 0.67, respectively. Results for improving predictions of yield grade by four methods-the Korean yield grade index equation, fat depth alone, regression and decision tree methods were 75.4%, 79.6%, 64.3% and 81.4%, respectively. We conclude that the decision tree method can easily predict yield grade and is also useful for increasing prediction accuracy rate.

• Plant Resources
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• v.4 no.2
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• pp.92-96
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• 2001

seeding rates(1.5,2.0,3.0 and 3.5$\ell$/10a). There were no differences in the yield components such as length of stem and ear diameter of stem number of branch, internode and ear, and yield of fresh and dry stem between the seeding methods with drilling and broadcasting, but yield components such as length of stem and ear, diameter of stem, number of branch, internode and ear, and yield of fresh and dry stem increased with seeding rates of from 2.5$\ell$ /10a to 3.5$\ell$/10a. Therefore potimum rates and methods of sowing were from 2.5$\ell$/10a to 3.5$\ell$/10a with seeding at the drilling and broadcasting.

• Asian-Australasian Journal of Animal Sciences
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• v.6 no.1
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• pp.123-126
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• 1993

Hand dibbling in rows produced higher (p < 0.05) fresh and dry matter (DM), fodder yield, higher plant density and cob yield than broadcasted. However, the varying seed rates (40, 50 and 55 kg/ha) did not affect (p < 0.05) the fresh and DM yield and cob yield except for 30 kg/ha seed rate which produced the lowest (p < 0.01). However, the overall average fresh fodder yield and the fresh and DM yield of cob were 24.97, 10.04 and 6.90 t/ha respectively. The overall average plant height (cm), cob/plant (nos.) plant/ha, (nos.) cob/ha (nos.) and weight (g) of one cob were 178, 1.11, 664141, 70104 and 145 respectively for both the sowing methods and the four seed rates. Crude protein contents of maize plant and cob by-products (8.12% and 7.34% respectively) indicated promising cattle feeds along with human food.

• Journal of Korea Foundry Society
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• v.3 no.4
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• pp.256-261
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• 1983

In this study, the variations of tensile strength and yield strength of Al-20% Si alloy were studied. Copper, magnesium and nickel as alloying elements added from 1% to 3% respectively. The temperature range was from room temperature to $350^{\circ}C$. The refinement of primary silicon crystal was treated with phosphorous addition. The results obtained are as follows: 1. Tensile strnegth and yield strength showed more increased strength in refining treated alloy than that of in nonrefining alloy at elevated temperature. 2. Tensile strength and yield strength were increased with the contents of copper. Tensile strength showed the maximum at $150^{\circ}C$, but yield strength was decreased with increasing temperature. 3. The effect of magnesium addition on tensile strength and yield strength showed the maximum at 1% addition and $150^{\circ}C$. 4. Tensile strength and yield strength showed a slight increase with the content changes of nickel and they were decreased with increasing temperature.

• Tribology and Lubricants
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• v.18 no.1
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• pp.16-23
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• 2002

For increasing the yield stress of ER fluids, the compressing ER electrode was developed and the compressing electrorheological (ER) behavior of anhydrous ER fluids in silicone oil of phosphorous ester cellulose powder was investigated. Under constant electric field, not only the current density but also the yield stress of anhydrous ER fluids were studied as varying the compressing length of ER electrode distance. From the experimental results the compressing of ER electrode had a large influence to the ER properties of anhydrous ER fluids. The current density was proportional to the compressing length of ER electrode under constant electric field and volume fraction also tile compressing yield stress was proportional to the volume fraction of dispersed particles under constant electric field and compressing length. When the ER electrode was compressed with 150mm after charging the electric field, 4 kV, tile yield stress of phosphoric ester cellulose ER fluids increased to thirteen times comparing with the yield stress measured at normal electrode.