• Geotechnical Engineering
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• v.12 no.4
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• pp.157-178
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• 1996

Current design methods for reinforced earth structures take no account of the magnitude of the strains induced in the tensile members as these are invariably manufactured from high modulus materials, such as steel, where straits are unlikely to be significant. With fabrics, however, large strains may frequently be induced and it is important to determine these to enable the stability of the structure to be assessed. In the present paper internal design method of analysis relating to the use of fabric reinforcements in reinforced earth structures for both stress and strain considerations is presented. For the internal stability analysis against rupture and pullout of the fabric reinforcements, a strain compatibility analysis procedure that considers the effects of reinforcement stiffness, relative movement between the soil and reinforcements, and compaction-induced stresses as studied by Ehrlich 8l Mitchell is used. I Bowever, the soil-reinforcement interaction is modeled by relating nonlinear elastic soil behavior to nonlinear response of the reinforcement. The soil constitutive model used is a modified vertsion of the hyperbolic soil model and compaction stress model proposed by Duncan et at., and iterative step-loading approach is used to take nonlinear soil behavior into consideration. The effects of seepage pressures are also dealt with in the proposed method of analy For purposes of assessing the strain behavior oi the fabric reinforcements, nonlinear model of hyperbolic form describing the load-extension relation of fabrics is employed. A procedure for specifying the strength characteristics of paraweb polyester fibre multicord, needle punched non-woven geotHxtile and knitted polyester geogrid is also described which may provide a more convenient procedure for incorporating the fablic properties into the prediction of fabric deformations. An attempt to define improvement in bond-linkage at the interconnecting nodes of the fabric reinforced earth stracture due to the confining stress is further made. The proposed method of analysis has been applied to estimate the maximum tensions, deformations and strains of the fabric reinforcements. The results are then compared with those of finite element analysis and experimental tests, and show in general good agreements indicating the effectiveness of the proposed method of analysis. Analytical parametric studies are also carried out to investigate the effects of relative soil-fabric reinforcement stiffness, locked-in stresses, compaction load and seepage pressures on the magnitude and variation of the fabric deformations.

• Korean Journal of Organic Agriculture
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• v.13 no.4
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• pp.401-412
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• 2005

This study was conducted to examine the effects of dietary Mogchotan(the mixture of charcoal and pyroligneous acid, 80:20, w/w) supplementation on fattening performance, fatty acid composition and the physico-chemical characteristics of meat in pigs. The present study was also stressed to investigate the possibility of industrial utilization of charcoal and pyroligneous acid as a livestock feed additive. Weight gain and feed conversion in pigs fed the Mogchotan supplemented diet were higher than those of the control group. In fatty acids composition, palmitic acid(C16:0) contents of Mogchotan treatment groups were lower than that of control group. However, Mogchotan supplementation increased C16:1, C18:0, C18:1, C18:2 and C18:3 contents when compared with control group pigs. Also, Mogchotan supplementation groups decreased saturated fatty acids level than control group. On the other hand, Mogchotan supplementation showed higher unsaturated fatty acids value, especially polyunsaturated fatty acids value compared to control group. The carcass pH of pigs fed the Mogchotan tended to be higher than control, but was not significantly different. The water holding capacity was significantly higher in pigs fed the 3.0% Mogchotan-supplemented diet than those of other treatment groups(p<0.05). Altogether, it has been suggested that dietary $1{\sim}3%$ of Mogchotan supplementation improved the fattening performance and meat quality in pigs.

• Korean Journal of Food Science and Technology
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• v.13 no.4
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• pp.314-318
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• 1981

In order to improve the storage stability of spray and freeze dried red ginseng extract powder packed in a bottle, the water vapor permeability of Al-foil laminate paper used for cap closure and shelf life of those products on various storage temperatures and relative humidities were investigated. The thickness of the laminate paper was $93{\pm}3\:{\mu}m$ and its physical properties were equal to standard of ASTM (B-377-66) The absorption rate of the freeze dried powder was 2-6 times greater than that of the spray dried powder at $37^{\circ}C$. Therefore it was considered that the laminate could be used for cap closures for the spray dried powder but unsuitable for the freeze dried powder. The shelf life of the spray dried powder was longer than that of the freeze-dried powder at $37^{\circ}C$.