• Journal of Environmental Science International
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• v.22 no.12
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• pp.1661-1669
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• 2013

This study conducted a laboratory simulation using artificial and natural rainfall in order to investigate the runoff characteristics of livestock resources through the analysis of the surface runoff water and infiltration water by rainfall intensity and fertilization level. Cattle manure and pig liquid fertilizer was used as livestock resource. As a result of this study, it was observed that the surface runoff occurred over 32 mm/hr rainfall intensity, and flow rate of the surface runoff water and the runoff ratio of contaminant parameters from livestock resource was increased, as rainfall intensity was stronger. With doubled fertilization level, T-N increased in compost and the amount of $COD_{Mn}$ runoff also considerably increased in liquefied fertilizer. In the case of natural rainfall, the runoff ratio of T-P clearly increased in compost and the T-N of final surface runoff ratio in compost and liquefied fertilizer was ranged from 0.13047 to 0.13623 with stronger rainfall intensity.

• Journal of the Korean Society of Industry Convergence
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• v.7 no.4
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• pp.349-354
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• 2004

The growth mode of the Si layers which were grown on Si(111) by using Ag as surfactant were investigated by intensity oscillations of the RHEED specular spot at the different temperatures. we found that the introduction of Ag as the surfactant alters the growth mode from a three-dimensional clustering mechanism to a two-dimensional layer-by-layer growth. In the growth of Si layers on Si(111) with a surfactant Ag, At $450^{\circ}C$, RHEED intensity oscillation was very stable and periodic from early stage of deposition to 32 ML. RHEED patterns during homoepitaxial growth at $450^{\circ}C$ was changed from $7{\times}7$ structure into ${\sqrt{3}}{\times}{\sqrt{3}}$ structures. Since the ${\sqrt{3}}{\times}{\sqrt{3}}$ structure include no stacking fault, the stacking fault layer seems to be reconstructed into normal stacking one at transition from the $7{\times}7$ structure to a ${\sqrt{3}}{\times}{\sqrt{3}}$ one. We also found that the number of the intensity oscillation of the specular spot for Si growth with a surfactant Ag was more than for Si growth without a surfactant. This result may be explained that the activation energy decrease for the surface diffusion of Si atoms due to segregation of the surfactant toward the growing surface.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.3
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• pp.365-371
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• 2001

The effects of light exposure and light intensity on surface color of Hanwoo (Korean native cattle) beef and color stability of fresh normal and DFD (dark, firm, dry) muscles during 7 days at $4{\pm}1^{\circ}C$ under three display conditions (Dark, Light1000 and Light3000) were investigated. The $L^*$, $a^*$, $b^*$, $C^*$ values and R630-R580 were significantly (p<0.05) higher in normal beef than in DFD beef. The $a^*$, $b^*$, $c^*$ values and R630-R580 of normal beef increased during the first day of display except Light3000 group, then gradually decreased over time. The surfaces of Hanwoo beef accumulated more metmyoglobin in the light than in the dark. Also, the rate of decrease in redness during refrigerated storage was enhanced by light exposure and increase in light intensity. Discolorations were more rapid in DFD beef than normal beef. Increasing light intensity promoted not only discoloration but also lipid oxidation. Therefore storage in the dark is effective in retarding the formation of a brown color in Hanwoo beef.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.29 no.4
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• pp.429-438
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• 2011

LiDAR technology is a combination of laser ranging, satellite positioning technology and digital image technology for study and determination with high accuracy of the true earth surface features in 3 D. Laser scanning data is typically a points cloud on the ground, including coordinates, altitude and intensity of laser from the object on the ground to the sensor (Wehr & Lohr, 1999). Data from laser scanning can produce products such as digital elevation model (DEM), digital surface model (DSM) and the intensity data. In Vietnam, the LiDAR technology has been applied since 2005. However, the application of LiDAR in Vietnam is mostly for topological mapping and DEM establishment using point cloud 3D coordinate. In this study, another application of LiDAR data are present. The study use the intensity image combine with some other data sets (elevation data, Panchromatic image, RGB image) in Bacgiang City to perform land cover classification using neural network method. The results show that it is possible to obtain land cover classes from LiDAR data. However, the highest accurate classification can be obtained using LiDAR data with other data set and the neural network classification is more appropriate approach to conventional method such as maximum likelyhood classification.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1996.03a
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• pp.73-80
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• 1996

Commerical purity aluminium , copper and STS 304 stainless steel sheets are welded by ultrasonic welding. The microstructures, x-ray diffraction profiles of planes , pole figures of the surface of original metal sheets are compared with those of the weld interface. The microstructures show disturbance and dark areas in the weld interface and grain refinement in the vicinity of the interface. The x-ray diffraction intensity of each plane in weld interface decreased in all metal sheets with exception of 9200) in steel sheet. The microstructure and x-ray diffraction intensity is affected by the mixture of deformation, heating and vibratin duringthe ultrasonic welding. Therefore, after the ultrasonic welding, the positions of the peak intensity in the pole figures are changed, the value of the maximum pole intensity is decreased in Al, is increased in copper and stainless steel. Very strong {100} <001> texture, strong {100} <001>,{123}<634> textures in original Al surface are transformed into weak, {100}<001>, {110}<112> and {112}<111> components in weld surface, weak (110) fiber is slightly changed to (110) fiber in copper, (100)and ${\gamma}$ fiber components are transformed into strong ${\gamma}$ fiber component in stainless steel.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.10
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• pp.1659-1670
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• 2001

It has been reported that cracks at mechanical fastener holes usually nucleate as elliptical corner cracks at the faying surface of the mechanical joints and grow as elliptical arc through cracks after penetrating the opposite surface. The weight function method is an efficient technique to calculate the stress intensity factors fur elliptical cracks using uncracked stress field. In this study the weight function method for three dimensional mixed-mode problem applied to elliptical comer cracks Is modified for elliptical arc through cracks and the stress intensity factors at two surface points of elliptical arc through cracks at mechanical fastener holes are analyzed by the weight function method. This study consists of two parts and in part I , the weight function method for elliptical arc through cracks is developed and verified.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.622-627
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• 2001

The object of this paper is to compare stress intensity factor that be calculated by Raju-Newman's equation, finite element method, and Vessel INTegrity analysis inner flaws(VINTIN) program for longitudinal semi-elliptical cracks in cylindrical vessel under inner pressure. For this, three-dimensional finite-element analyses were performed to obtain the stress intensity factors for various surface cracks with t/R = 0.1. The finite element meshes were designed for various crack shapes with t/R of 0.1. The crack depth to thickness ratio, a/t, was set to 0.2 and 0.5 matching Raju-Newman's equation. The crack depth to length ratio, a/c, was set to 0.2 and 0.4 in the same way and 0.33 was added to extend the range of crack configuration. Finite Element Analyses(FEA) were performed using the commercial FEA program ABAQUS. The results showed that the Raiu-Newman solutions were about 4-10% lower than FEA's using symmetric model of one-eighth of a vessel and close to those of FEA using symmetric model or one-forth or a vessel. Ana VINTIN solutions were nearly equal to those or Raju-Newman.

• Journal of Applied Reliability
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• v.17 no.4
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• pp.325-331
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• 2017

Purpose: There is active research that improves both reliability and fatigue life of structures which widely used in the aerospace fields of defense industry. The effects of three parameters (pressure, peening time, nozzle distance) on Almen intensity and coverage will be investigated by using the experimental and analyzed data. Methods: we employed a Box-Behnken design. Additionally, to verify the validity of the optimal condition obtained from experimental results, metallurgical analyses of the shot-peened aerospace part were conducted with respect to surface morphology, residual stress. Results: Optimal shot peening condition is determined as (distance, pressure, time) by optimizing simultaneously the two responses of intensity and coverage. At the optimal peening condition the prediction interval for Almen intensity is well within the required range. And, the validity of the condition was checked by using the real aerospace aluminum alloy plate. Conclusion: Shot peening introduces significant levels of compressive residual stress and induces improves both reliability and fatigue life of structures.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.7
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• pp.1705-1712
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• 1994

Hilbert problems are derived to evaluate thermal stress intensity factors for a partially insulated crack subjected to vertically uniform heat flow in infinite bonded dissimilar materials. In case of fully insulated crack surface, the present solutions of thermal stress intensity factors are reduced into the same as the previous results. For the homogeneous material, mode II thermal stress intensity factor only exists. However, in the bonded dissimilar materials, both mode I and II thermal stress intensity factors are obtained. Specially, in this case, mode II thermal stress intensity factor is dominent. Also, thermal stress intensity factors are strongly influenced by the material properties. Thermal stress intensity factors decrease when the degree of insulation decreases.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1999.06a
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• pp.297-302
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• 1999

Finite element analysis is peformed about the crack propagation in half-space due to sliding contact. The analysis is based on linear elastic fracture mechanics and stress intensity factor concept. The crack location is fixed and the friction coefficient between asperity and half-space is varied to analyze the effect of surface friction on stress Intensity factor for horizontal crack. The crack propagation direction is predicted based on the maximum range of shear and tensile stress intensity factor.