• Food Science of Animal Resources
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• v.22 no.3
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• pp.228-233
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• 2002

To investigate the effects of submersion aging in chilled water on tenderness and microbial growth of vacuum-packed beef, the semimembranosus muscles of Hanwoo (Korean cattle) was sampled at a commercial meat plant at 24 hrs postmortem. The samples were cut to 2.5 cm thick steaks and randomly assigned to following two treatments. The samples were stored in conventional refrigerator at 4$^{\circ}C$ after vacuum packaging for control whereas the other vacuum-packed samples were submersed in chilled water at 1$^{\circ}C$ for treatment, and both samples were stored for 14 days to measure total plate counts (TPC), sarcomere length, free calcium concentration, shear farce value and myofibrillar fragmentation index (MFI). The sarcomere length of treatment was significantly (p<0.05) longer than that of control at 3 days aging. Result suggested that submersion in chilled water of vacuum-packed beef might be effective to improve tenderness of meat compared to storage in conventional refrigerator. There were no significant differences in the shear force and MFI between control and treatment during storage. However, the free calcium concentration of samples from treatment was significantly (p<0.05) higher than that of control at 7 days of ageing. This result indicated that the lower shear force value and the longer sarcomere length of samples from treatment might be due to increasing the free calcium ion concentration in sarcoplasm during storage. On the other hands, samples from control showed significantly (p<0.05) higher number of microbial (TPC) compared to treatment during storage. from results obtained, submersion in chilled water of vacuum-packed beef could be recommended as a desirable aging method to improve tenderness of Hanwoo compared to aging in conventional refrigerator.

• Journal of the Microelectronics and Packaging Society
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• v.8 no.3
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• pp.43-47
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• 2001

Sn-3Ag-8Bi-5In was developed for the intermediate melting point solder. Although In-contained solder is expensive, its melting point is lower than these of Sn-Ag-Cu alloys. Sn-3Ag-8Bi-5In solder used for this research has a melting range of 188~$204^{\circ}C$. On this study wetting characteristics of Sn-3Ag-8Bi-5In were evaluated in order to investigate its availability as a Pb-free solder. Wettabilities of Sn-37Pb and Sn-3.5Ag solders were also studied to compare these of the Sn-3Ag-8Bi-5In. Experimental results showed that the zero-cross-time and wetting time at $240^{\circ}C$ for the Sn-3Ag-8Bi-5In were 1.1 and 2.2 second respectively. These values are a little better than these of Sn-37Pb and Sn-3.5Ag solders. The equilibrium wetting farce of the Sn-3Ag-8Bi-5In was 5.8 mN at $240^{\circ}C$, and it was tuned out to be a little higher than that of Sn-3.5Ag and lower than that of Sn-37Pb.

• Journal of the Korean Geotechnical Society
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• v.20 no.9
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• pp.57-64
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• 2004

In order to establish the design method of anchored retention walls in cut slope, the behavior of anchored retention walls and backside ground needs to be investigated and checked in detail. In this study, the behavior of anchored retention walls was investigated by instrumentation installed in cut slope for an apartment construction site stabilized by a row of piles and anchored retention walls. When the anchor was installed at each excavating stages, the horizontal deflection of retention wall decreased, while the horizontal deformation of backside ground increased. The deflection of anchored retention wall decreased as the anchor was prestressed. The prestressed anchor farce has a great effect on the deflection of retention walls, while it has little effect on the deformation of its backside ground. The maximum horizontal deflection of anchored retention walls was developed between $1\%\;and\;4\%$ of excavation depth, which are $2\~8$ times larger than max. horizontal deflection of anchored retention walls including rock layers with backside horizontal ground. Meanwhile, SLOPILE (ver. 3.0) program analyzes the slope stability effects for anchored retention walls. As a result of analysis on slope stability analysis, the lateral earth pressure applied at anchored retention piles could be used as the mean values of empirical lateral pressures using anchored retention wall with horizontal ground at its backside.

• Journal of the Korean Geotechnical Society
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• v.22 no.8
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• pp.129-136
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• 2006

Engineered mixtures, which consist of rigid sand particles and soft fine-grained rubber particles, are tested to characterize their small and large-strain responses. Engineered soils are prepared with different volumetric sand fraction, sf, to identify the transition from a rigid to a soft granular skeleton using wave propagation, $K_{o}-loading$, and triaxial testing. Deformation moduli at small, middle and large-strain do not change linearly with the volume fraction of rigid particles; instead, deformation moduli increase dramatically when the sand fraction exceeds a threshold value between sf=0.6 to 0.8 that marks the formation of a percolating network of stiff particles. The friction angle increases with the volume fraction of rigid particles. Conversely, the axial strain at peak strength increases with the content of soft particles, and no apparent peak strength is observed in specimens when sand fraction is less than 60%. The presence of soft particles alters the formation of force chains. While soft particles are not part of high-load carrying chains, they play the important role of preventing the buckling of stiff particle chains.