• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.396-400
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• 2007

Various ways of automated guideway transit construction are being planned recently owing to the policies of the national government and local municipalities as well as increasing investment from the private sector. Particularly, the increase in the private investment is increasing greatly in SOC (Social Overhead Cost). This trend of promoting private sector investment must be conducted on the basis of a thorough analysis of the economic feasibility of the project from the government and construction companies in the private sector. In other words, an accurate cost analysis of initial investment cost (Construction cost), maintenance/repair cost, profit making through the operation of the concerned facilities, cost of dissolution, etc. in terms of the life cycle is very much in need. Nevertheless, the analysis of uncertainty factors and its probabilistic theory are in need of development so that they can be used in the analysis of the economic feasibility of a construction project. First of all, the actual studies on maintenance/repair cost of automated guideway transit are scarce as of yet, prohibiting an accurate computation of the cost and its economic analysis. Accordingly, this study focused on the uncertainty analysis of the economic feasibility for civil engineering structures among automated guideway transit construction projects based on the rapidly increasing investment on such structures from the private sector. For this research purpose, a cost classification system for the automated guideway transit is proposed, first of all, and the data On the cost cycle of the civil structure facilities and their unit cost are collected and analyzed. Then, the uncertainty in the cost is analyzed from the perspective of LCC. In consideration of the current status with almost no. studies on maintenance/repair of such facilities, it is expected that the cost classification system and the uncertainty analysis technique proposed in this study will greatly enhance LCC analysis and economic feasibility studies for automated guideway transit projects in the future.

• The Korean Journal of Rheology
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• v.11 no.2
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• pp.143-152
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• 1999

Using a Rheometrics Fluids Spectrometer(RFS II), the steady shear flow and the small-amplitude dynamic viscoelastic properties of three kinds of semi-solid food materials(mayonnaise, tomato ketchup, and wasabi) have been measured over a wide range of shear rates and angular frequencies. The shear rate dependence of steady flow behavior and the angular frequency dependence of dynamic viscoelastic behavior were reported from the experimentally measured data. In addition, some viscoplastic flow models with a yield stress term were employed to make a quantitative evaluation of the steady flow behavior, and the applicability of these models was also examined in detail. Furthermore, the correlations between steady shear flow(nonlinear behavior) and dynamic viscoelastic(linear behavior)properties were discussed using the modified power-law flow equations. Main results obtained from this study can be summarized as follows : (1) Semi-solid food materials are regarded as viscoplastic fluids having a finite magnitude of yield stress, and their flow behavior shows shear-thinning characteristics, exhibiting a decrease in steady flow viscosity with increasing shear rate. (2) The Herschel-Bulkley, Mizrahi-Berk, and Heinz-Casson models are all applicable to describe the steady flow behavior of semi-solid food materials. Among these models, the Heinz-Casson model has the best validity. (3) Semi-solid food materials show a stronger shear-thinning behavior at shear rate region higher than a critical shear rate where a more progressive structure breakdown takes place. (4) Both the storage and loss moduli are increased with increasing angular frequency, but they have a slight dependence on angular frequency. The elastic behavior is dominant to the viscous behavior over a wide range of angular frequencies. (5) All of the steady flow, dynamic, and complex viscosities are well satisfied with the power-law model behavior. The relationships between steady shear flow and dynamic viscoelastic properties can well be described by the modified forms of the power-law flow equations.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.2
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• pp.196-204
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• 2011

Heat-moisture treatment (HMT) was applied to 4 samples of rice flours, Goami (GM), Taeguk (TG), Choochung (CC) and Koshihikari (KSHK), of which amylose contents were 31.5, 32.3, 24.3, and 23.3%, respectively. Wet-milled rice flours were dried, moisture content adjusted to 21, 24, 27 and 30%, respectively, and autoclaved at 100 and $105^{\circ}C$ for 30~90 min. The changes on swelling, solubility, RVA (rapid visco analyser) paste viscosities and gel strength were observed. In GM and TG, peak viscosity (PV) and breakdown (BD) decreased and no peak appeared as moisture and treatment time increased by HMT. In CC, FV increased notably with big increase of PV and setback (SB) by HMT compared to the other rice flours. BD in all the samples decreased as moisture, temperature, and time increased by HMT. RVA pasting properties of HMT GM and HMT TG were changed remarkably under conditions of moisture 21%, $100^{\circ}C$ and 30 min whereas for HMT CC and HMT KSHK, higher temperature or more time was required at the same mois ture levels. The swelling power, solubility and gel strength increased by HMT. Gel strength correlated positively with SB (r=0.78, p<0.01) and negatively with BD (r=-0.71, p<0.01) and PV (r=-0.36, p<0.05) resulting from strengthening the structure of starch granules in rice flours by HMT.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.4
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• pp.704-713
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• 1997

This study was conducted to describe qualitatively the protein metabolism of pigs during growth depending on the feed protein quality and to describe quantitatively amino acids requirements, using a simulation model. The used model has a non-linear structure. In the used model, the protein utilization system of a pig, which is in the non-steady-state, is described with 15 flux equations and 11 differential equations and is composed with two compartments. Protein deposition(g/day) of pigs on the 30th, 60th, 90th, and 120th day of feeding duration with three-quality protein, beginning with body weight 20kg, were calculated according to the empirical model, PAF(the product of amino acid functions) of Menke, and was used as object function for the simulation. The mean of relative difference between the simulated protein deposition and PAF calculated values, lied in a range of 8.8%. The simulated protein deposition showed different behavior according to feed protein quality. In the high-quality protein, it showed paraboloidal form with extending growth simulation up to 150eh day. So the maximum of protein deposition was acquired on the 105th day of simulate growth time and then it decreased fast. In the low-quality protein, this form of protein deposition in the course of simulated growth did not appear until 150th day. The simulated protein mass also showed a difference in accordance with feed protein quality. The difference was small on the 30th day of simulated growth, but with duration of the simulated growth it was larger. On the 150th day the simulated protein deposition of high quality protein was 1.5 times higher as compared to the low-quality protein. The simulated protein synthesis and break-down rates(g/day) in the whole body showed a parallel behavior in the course of growth, according to feed protein quality. It was found that the improvement of feed protein quality increased protein deposition in the whole body through a increase of both protein synthesis and breakdown during growth. Also protein deposition efficiency, which was calculated from simulated protein deposition and protein synthesis, showed a difference in dependence on the protein qualify of feed protein. The protein deposition efficiency was higher in pigs fed with high quality protein, especially at the simulation time 30th day. But this phenomena disappeared with growth, so on the 150th day of growth, the protein deposition of the high feed protein quality was lowest among the three different quality of feed protein. The simulated total requirement of the 10 essential amino acids for the growth of pigs was 28.1(g/100g protein), similar to NRC. The requirement of lysine was 4.2(g/100g protein).

• Journal of Korean Society of Forest Science
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• v.19 no.1
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• pp.1-23
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• 1973

The results of ground vegetation experiment conducted at completely denuded forestland in the mudstone region are summerized as follows: On the reaults of soiling quantity the effect of soiling was observed where depth of soiling over 10 cm was practiced, and a plot where treated with 15cm soiling and without fertilizer showed poor growth and it was even worser than the plot where soiling was practiced only 1 cm in thikness but applied adequate amount of fertilizers. The depth of slits between 30cm and 40cm showed no significant difference in the effect. A plot where covered with vegetation bag showed somewhat better results in seed loss and early growth but no differences observed in the fall result over the none covered plot. And then, it is recommendable to have soiling over 10cm in thikness with slit of 30cm and 30cm in depth and to apply 30 gram of fertilizer (22;22:11, 50 gram) per slit. On various soiling materials trial there were no striking differences in the effect of soiling between weathered granite soil, wheathered tuffs soil and weathered mudstone soil. In the treatment with various green materials, a plot treated with straw mat showed a significant difference at 1 percent. The results show that weathered mudstone soil is effective to use as soiling materials and straw mat treatment was better. On forest fertilization trial, in the mudstone region where red and black pine trees already existing at a rate of 2,000-3,000 trees per hectare had applied 110kg of compound fertilizers (9:12:3 and 22:22:11) per hectare basis in terms of plant nutrient. As a result, the difference in effect between the compound fertilizers was not found however the leaf color and leaf length of the fertilizer added plot showed darker and longer at 30 percent over the no fertilizer received plot. Compound fertilizers, 14:37:12 and 9:12:3 were applied to alder trees at a rate of 20 gram and 40 gram per tree in terms of plant nutrient and a remarkable growth accelerantion was observed where 40 grams of plant nutrient applied. The effect difference between the compound fertilizers was not found. On investigation of tree root elongation, forty years old red pine trees showed only 15cm tap root elongation through mudstone while black pine had 23 cm tap root elongation. The total length of supporting root elongtion of red and black pines showed 20 and 13 meters, respectively. The tap roots of Black locusts were not able to elongate through mudstone, however, the supporting roots tended to develop to the underneath of pine tree where some moisture content is available. Black locusts And grown on the residual soil of mudstone normally die between 8 to 10 years. The red pine trees show flat in tree shape while black pine had triangle in the shape. With the results it can be said that in an artificial reforestation in denuded forest land of the mudstone region the adequate slit and enough amount of fertiliizer application must be provided for the succesful performance of the program. On integrated experimental results of 1972. for the establishment of ground vegetation on the completely denuded forest land in mudstone region, soiling could be effectively practiced with weathered mudstone soil and it would not specially necessiate to have either weathered granite or tuffssoil for the soiling. And the soiling depth should be more than 10 cm in thickness. Among green materials used the straw mat proved to be the most effective reatment. Three major factors which enable to establish ground vegetation by the shortest period of time: A. Physical improvement of soil is necessary to breakdown of the horizontal cracks sushas Slit, contour line plot, seeding hole and etc., and soiling with weathered mudstone soil. B. Chemical improvement of soil: is needed sufficient amount of fertilizer application 300~400kg ha, $N+P_2O_5+K_2O$), and increased production of ground covering and expedite resolution of the vegetation (ground vegetation, fallen leaves and twigs). C. Complete establishment of the basic structure for the erosion control (Prevention of surface soil erosion)