• Proceedings of the Korean Geotechical Society Conference
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• 2010.03a
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• pp.1164-1171
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• 2010

Korea is considered to be a seasonal frozen soil area that is thawed in the spring, and most of the area is frozen in winter as to the characteristic of geography. In the current design codes for anti-freezing layer, the thickness of anti freezing layer is calculated by freezing depth against the temperature condition. Therefore, they have a tendency of over-design and uniform thickness without the considerations of thermal stability, bearing capacity and frost susceptibility of materials. So, it is essential for studying the appropriateness and bearing capacity besides the seasonal and mechanical properties of pavement materials to take a appropriate and reasonable design of the road structure. In this research, the evaluation of frost susceptibility on subgrade, ant-freezing layer, sub base was conducted by means of the mechanical property test and laboratory field road model downed scale experiment. The temperature, heaving amount, heaving pressure and unfrozen water contents of soil samples, the subgrade, anti-freezing layer, sub base soils of highway construction site, were measured to determine the frost susceptibility.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.3
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• pp.191-201
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• 1987

Seasoned sardine meat was prepared to extend the use of sardine for human consumption, and processing conditions and storage stability of frozen seasoned sardine meat were studied during storage at $-20^{\circ}C$. The fish was beheaded, gutted and cleaned in a washing tank. The washed fish was then put through a belt-drum type meat separator which separates the flesh iron the bone and skin. Mechanically deboned fish meat was mixed with $20.6\%$ emulsion curd, $0.5\%$ table salt, $2.0\%$ sugar, $0.4\%$ sodium bicarbonate, $0.2\%$ polyphosphate, $0.1\%$ monosodium glutamate, $0.3\%$ onion powder, $0.1\%$ garlic powder, $0.1\%$ ginger powder, $3.0\%$ soybean protein and $0.1\%$. In sodium erythorbate. This seasoned sardine meat was frozen with contact freezer, packed in a carton box and then stored at $-20^{\circ}C$. The pH, volatile basic nitrogen, viable cell counts, peroxide value, carbonyl value, thiobarbituric acid value, taste compounds, fatty acid composition, salt extractable nitrogen, drip, texture, and color values of the products were determined during frozen storage. The results showed that lipid content in products could be controlled by using emulsion curd, and flavor and texture could be improved by adding spices and soybean protein, and lipid oxidation could be retarded by $0.1\%$ sodium erythorbate. Judging from the results of chemical experiments and sensory evaluation, the products can be preserved in a good quality for 120 days during frozen storage.

• Geomechanics and Engineering
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• v.8 no.3
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• pp.391-414
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• 2015

In this paper, stabilities of a plane slide rock slope under different hydraulic distributions were studied based on the nonlinear Barton-Bandis (B-B) failure criterion. The influence of various parameters on the stability of rock slopes was analyzed. Parametric analysis indicated that studying the factor of safety (FS) of planar slide rock slopes using the B-B failure criterion is both simple and effective and that the effects of the basic friction angle of the joint (${\varphi}_b$), the joint roughness coefficient (JRC), and the joint compressive strength (JCS) on the FS of a planar slide rock slope are significant. Qualitatively, the influence of the JCS on the FS of a slope is small, whereas the influences of the ${\varphi}_b$ and the JRC are significant. The FS of the rock slope decreases as the water in a tension crack becomes deeper. This trend is more significant when the flow outlet is blocked, a situation that is particularly prevalent in regions with permafrost or seasonal frozen soil. Finally, the work is extended to study the reliability of the slope against plane failure according to the uncertainty from physical and mechanics parameters.

• Journal of Powder Materials
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• v.21 no.3
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• pp.191-195
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• 2014

This study reports a simple way of fabricating the porous Cu with unidirectional pore channels by freeze drying camphene slurry with Cu oxide coated Cu powders. The coated powders were prepared by calcination of ball-milled powder mixture of Cu and Cu-nitrate. Improved dispersion stability of camphene slurry could be achieved using the Cu oxide coated Cu powders instead of pure Cu powders. Pores in the frozen specimen at $-25^{\circ}C$ were generated by sublimation of the camphene during drying in air, and the green bodies were sintered at $750^{\circ}C$ for 1 h in $H_2$ atmosphere. XRD analysis revealed that the coated layer of Cu oxide was completely converted to Cu phase without any reaction phases by hydrogen heat treatment. The porous Cu specimen prepared from pure Cu powders showed partly large pores with unidirectional pore channels, but most of pores were randomly distributed. In contrast, large and aligned parallel pores to the camphene growth direction were clearly observed in the sample using Cu oxide coated Cu powders. Pore formation behavior depending on the initial powders was discussed based on the degree of powder rearrangement and dispersion stability in slurry.

• Food Science and Biotechnology
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• v.15 no.3
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• pp.453-457
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• 2006

Activity and stability of kiwifruit actinidine was determined in various conditions of pH, salt, and temperature using N-${\alpha}$-CBZ-lysine P-nitrophenyl ester as the substrate. Actinidine activity was low below pH 6, and undetectable below pH 3. The enzyme was stable in a pH range of 6.0-8.5. At $4^{\circ}C$ the enzyme was inactive in the presence of greater than 36% vinegar and in 2 M NaCl. Actinidine at $25^{\circ}C$ was unstable in 24% vinegar but stable in up to 3 M NaCl. With regard to freeze-thaw stability, actinidine retained 85% residual activity after being frozen at $-20^{\circ}C$ for 3 days. Based on Arrenius and Lineweaver-Burk plots, actinidine became unstable at greater than $45^{\circ}C$ with only 30% residual activity remaining after 6 min. The Km, kcat, and kcat/Km values of actinidine were $56\;{\mu}M$, 67/sec, and $1.2\;{\mu}M/sec$, respectively.

• Korean Journal of Food Science and Technology
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• v.22 no.2
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• pp.162-167
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• 1990

10% salted egg yolk containing 12-21% e99 white (RI 42-45) was stored at $-15^{\circ}C\;and\;-25^{\circ}C$. Changes of appearent viscosity and emulsification capacity were measured monthly(1-6 months). Viscosity, oil particle size and emulsion stability of mayonnaise which was prepared with these yolks for each storage time were also tested . In salted e99 yolk, viscosity was increased gradually with increasing the storage time, and further increased in the yolk of less egg white (higher RI), stored at $-25^{\circ}C\;than\;-15^{\circ}C$. Emulsification capacity was decreased gradually with increasing the storage time. In mayonnaise, which was Prepared with these frozen egg folks, oil Particle size became smaller gradually with increasing the storage time of egg folk, and further became smaller in the egg yolks containing low levels of egg white , stored at $-25^{\circ}C\;than\;-15^{\circ}C$. The viscosity of mayonnaise was decreased by about 2 months storage of e99 yolk, and restored thereafter, emulsion stability was decreased by 3-4 months storage of egg yolk and restored slightly thereafter.

• Journal of Korean Orthopaedic Sports Medicine
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• v.10 no.2
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• pp.54-60
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• 2011

Puropse: To evaluate the outcome of arthroscopic posterior cruciate ligament (PCL) reconstruction using fresh-frozen achilles allograft tendon with preservation of ligament remnant or elongated ligament. Materials and Methods: From October 2004 to March 2010, we performed PCL reconstruction with Achilles tendon allografts in 22 complete rupture patients. Mean age was 31.5 years. 14 cases were male and 8 cases were female. Average follow-up period was 3 years and 7 months, range from 1 year to 6 years and 4 months. Subjective and objective parameters were utilized in analyses, such as the mean range of motion, post. drawer test, Lysholm knee score, Tegner activity score, IKDC score, and second look arthroscopic examination. Results: Postoperative Lysholm knee score, IKDC scores, Tegner activity scale, and posterior displacement by the Telos stress test demonstrated statistically significant improvement compared to the preoperative state. Conclusion: Arthroscopic PCL reconstruction using fresh-frozen achilles allograft tendon with preservation of ligament remnant showed good clinical results and posterior stability.

• Food Science of Animal Resources
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• v.21 no.4
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• pp.292-299
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• 2001

Chicken surimi from mechanically deboned chicken meat was prepared with 0.2% oleoresin spices such as rosemary, thyme, sage, mace, marjoram, and bay. Samples were stored at -18$\^{C}$ for 14 weeks to observe quality change including lipid oxidation, color and textural properties. The pH of surimi decreased from pH 7.44∼7.58 stored at 1 day to pH 7.03∼7.13 stored at 14 weeks. The control surimi showed higher level of pH during storage periods. Color stabiilty of surimi decreased during frozen storage both in control and oleoresin added surimi. Control surimi comparatively maintained higher color stability during frozen storage because of higher L* and a* values, and lower b*. On the contrary, the marjoram addition significantly decreased L* and a* value, and increased b* value compared with other oleoresins. Therefore, the color of surimi seems to be affected original color of oleoresin spice itself. Gel strength showed loser level in oleoresin added surimi than control surimi. Oleoresin spices inhibited lipid oxidation significantly because less thiobarbituric acid-reactive substance(TBARS) were accumulated in oleoresin added surimi than control surimi. Sage was the most effective in minimizing lipid oxidation in frozen surimi as TBARS of sage added surimi stored for 14 weeks maintained only 42% compared with that of control. In conclusion, the 6 kinds of oleoresin in this experiment retarded oxidative rancidity in chicken surimi but there was no beneficial effect on the surface color and gel strength.

• Korean Journal of Food Science and Technology
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• v.16 no.2
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• pp.127-132
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• 1984

Processing conditions of filefish steaks and effect of soybean protein on quality during frozen storage were investigated. Additives which is added to the filefish meat were 1% of table salt, 0.2% polyphosphate, 0.5% of sodium bicarbonate, 0.2% of monosodium glutamate, 0.2% of red pepper powder, 0.4% of white pepper powder, 0.2% of garlic powder and 0.2% of nutmeg. The mixture was minced in the stone mortar and then stored at -3 to $-5^{\circ}C$ for two days prior to frozen storage. The benefical effects of adding 5% of soybean protein to the filefish steaks were the control of free drip, oxidative rancidity and in texture that exhibited the improvement of quality. The quality of frozen filefish steaks, by sensory evaluvation, was not inferior to that of hamburger on the market.

• Food Science and Preservation
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• v.16 no.4
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• pp.518-524
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• 2009

The quality attributes of frozen dough mixed with milk proteins (casein: C and whey protein: W) and polysaccharides (sodium alginate: A and ${\kappa}-carrageenan:$ K), and with 1.6% (w/w) wheat flour, were investigated to improve the quality of dough. Addition of milk protein-polysaccharide mixtures increased water absorption, as assessed by farinography, compared with control material. Dough prepared with CA and WA mixtures showed longer development times and increased valorimeter values compared with control samples. However, addition of milk protein-polysaccharide mixtures decreased dough stability, elasticity, and strength. Gelatinization temperature and the temperature at maximum viscosity, as measured by amylography, increased on addition of milk protein-polysaccharide mixtures, but the maximum viscosity decreased compared with control samples. The control showed a lower dough volume than did dough prepared with CA and WA mixtures. These results indicate that addition of milk protein-polysaccharide mixtures, especially CA and WA, improved the quality of frozen dough,and could be useful to prevent bread becoming stale.